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(affects Type 1 AND Type 2 Diabetics)

General Treatment Pathophysiology

   

Pharmacology

  • Targeting (FABP4) aP2 may prevent and treat type 2 diabetes and atherosclerosis (doi:10.1038/nature05844) Adipocyte fatty-acid-binding protein, aP2 (FABP4) is expressed in adipocytes and macrophages, and integrates inflammatory and metabolic responses. Studies in aP2-deficient mice have shown that this lipid chaperone has a significant role in several aspects of metabolic syndrome, including type 2 diabetes and atherosclerosis. Here we demonstrate that an orally active small-molecule inhibitor of aP2 is an effective therapeutic agent against severe atherosclerosis and type 2 diabetes in mouse models. In macrophage and adipocyte cell lines with or without aP2, we also show the target specificity of this chemical intervention and its mechanisms of action on metabolic and inflammatory pathways. Our findings demonstrate that targeting aP2 with small-molecule inhibitors is possible and can lead to a new class of powerful therapeutic agents to prevent and treat metabolic diseases such as type 2 diabetes and atherosclerosis.

  • Higher exposure to sulfonylureas was associated with increased mortality among newly treated type 2 diabetics. Significant diabetic outcomes are dependent upon the path of control. (CMAJ[2006] 174 (2). doi:10.1503/cmaj.050748) Background: Over the past 30 years, the relation between use of sulfonylureas to treat type 2 diabetes and the risk of cardiovascular events has been vigorously debated. The purpose of this study was to determine if the risk of death changes with level of exposure to sulfonylurea drugs. Methods: This was a retrospective, inception cohort study using administrative data from Saskatchewan Health (1991– 1999). The 5795 subjects, identified by their first-ever dispensation for an oral antidiabetic agent, were grouped according to their use of such agents during follow-up. Potential subjects using insulin or combination therapy were excluded. Exposure level was defined by daily dose and degree of adherence. Separate multivariate Cox proportional-hazard models were constructed for each monotherapy group and used to calculate the risk of death associated with higher versus lower exposure category. Disease severity indicators were identified among the administrative data and entered as covariates in each model. The main outcomes were all-cause mortality and death from an acute ischemic event. Results: The mean age of the cohort members was 66.3 (standard deviation [SD] 13.4) years; 43.4% were female; and their mean duration of follow-up was 4.6 (SD 2.1) years. First-generation sulfonylureas were used exclusively by 120 subjects; glyburide, by 4138; and metformin, by 1537. A greater risk of death was associated with higher daily doses of the first-generation sulfonylureas (adjusted hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.0–4.7) and glyburide (HR 1.3, 95% CI 1.2–1.4), but not metformin (HR 0.8, 95% CI 0.7–1.1). Similar associations were observed for death caused by an acute ischemic event. Interpretation: Higher exposure to sulfonylureas was associated with increased mortality among patients newly treated for type 2 diabetes. The same relation was not observed with metformin. This implies that the manner in which blood glucose concentration is lowered may be as important as achieving recommended glucose targets.

  • Fenofibrate did not significantly reduce the risk of the primary outcome of coronary events in a large mixed primary and secondary prevention study in type 2 diabetes (The Lancet[2005] 366:1849-1861) Background Patients with type 2 diabetes mellitus are at increased risk of cardiovascular disease, partly owing to dyslipidaemia, which can be amenable to fibrate therapy. We designed the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study to assess the effect of fenofibrate on cardiovascular disease events in these patients.Methods We did a multinational, randomised controlled trial with 9795 participants aged 50–75 years, with type 2 diabetes mellitus, and not taking statin therapy at study entry. After a placebo and a fenofibrate run-in phase, we randomly assigned patients (2131 with previous cardiovascular disease and 7664 without) with a total-cholesterol concentration of 3·0–6·5 mmol/L and a total-cholesterol/HDL-cholesterol ratio of 4·0 or more or plasma triglyceride of 1·0–5·0 mmol/L to micronised fenofibrate 200 mg daily (n=4895) or matching placebo (n=4900). Our primary outcome was coronary events (coronary heart disease death or non-fatal myocardial infarction); the outcome for prespecified subgroup analyses was total cardiovascular events (the composite of cardiovascular death, myocardial infarction, stroke, and coronary and carotid revascularisation). Analysis was by intention to treat. The study was prospectively registered (number ISRCTN 64783481).FindingsVital status was confirmed on all but 22 patients. Averaged over the 5 years' study duration, similar proportions in each group discontinued study medication (10% placebo vs 11% fenofibrate) and more patients allocated placebo (17%) than fenofibrate (8%; p<0·0001) commenced other lipid treatments, predominantly statins. 5·9% (n=288) of patients on placebo and 5·2% (n=256) of those on fenofibrate had a coronary event (relative reduction of 11%; hazard ratio [HR] 0·89, 95% CI 0·75–1·05; p=0·16). This finding corresponds to a significant 24% reduction in non-fatal myocardial infarction (0·76, 0·62–0·94; p=0·010) and a non-significant increase in coronary heart disease mortality (1·19, 0·90–1·57; p=0·22). Total cardiovascular disease events were significantly reduced from 13·9% to 12·5% (0·89, 0·80–0·99; p=0·035). This finding included a 21% reduction in coronary revascularisation (0·79, 0·68–0·93; p=0·003). Total mortality was 6·6% in the placebo group and 7·3% in the fenofibrate group (p=0·18). Fenofibrate was associated with less albuminuria progression (p=0·002), and less retinopathy needing laser treatment (5·2% vs 3·6%, p=0·0003). There was a slight increase in pancreatitis (0·5% vs 0·8%, p=0·031) and pulmonary embolism (0·7% vs 1·1%, p=0·022), but no other significant adverse effects. Interpretation Fenofibrate did not significantly reduce the risk of the primary outcome of coronary events. It did reduce total cardiovascular events, mainly due to fewer non-fatal myocardial infarctions and revascularisations. The higher rate of starting statin therapy in patients allocated placebo might have masked a moderately larger treatment benefit.

  • DCCT intensively treated with insulin (ITT) fails significance in primary (time-to-initial-event) analysis of Cardiovascular Disease (CVD) in 11 year EDIC Follow-Up. (In a secondary analysis an ITT population intensively treated with insulin over about one-third the total observation period had fewer cardiovascular events than a conventionally treated ITT population) (NEJM[2005]353:2643-2653) Background Intensive diabetes therapy aimed at achieving near normoglycemia reduces the risk of microvascular and neurologic complications of type 1 diabetes. We studied whether the use of intensive therapy as compared with conventional therapy during the Diabetes Control and Complications Trial (DCCT) affected the long-term incidence of cardiovascular disease. Methods The DCCT randomly assigned 1441 patients with type 1 diabetes to intensive or conventional therapy, treating them for a mean of 6.5 years between 1983 and 1993. Ninety-three percent were subsequently followed until February 1, 2005, during the observational Epidemiology of Diabetes Interventions and Complications study. Cardiovascular disease (defined as nonfatal myocardial infarction, stroke, death from cardiovascular disease, confirmed angina, or the need for coronary-artery revascularization) was assessed with standardized measures and classified by an independent committee. Results During the mean 17 years of follow-up, 46 cardiovascular disease events occurred in 31 patients who had received intensive treatment in the DCCT, as compared with 98 events in 52 patients who had received conventional treatment. Intensive treatment reduced the risk of any cardiovascular disease event by 42 percent (95 percent confidence interval, 9 to 63 percent; P=0.02) and the risk of nonfatal myocardial infarction, stroke, or death from cardiovascular disease by 57 percent (95 percent confidence interval, 12 to 79 percent; P=0.02). The decrease in glycosylated hemoglobin values during the DCCT was significantly associated with most of the positive effects of intensive treatment on the risk of cardiovascular disease. Microalbuminuria and albuminuria were associated with a significant increase in the risk of cardiovascular disease, but differences between treatment groups remained significant (P<0.05) after adjusting for these factors. Conclusions Intensive diabetes therapy has long-term beneficial effects on the risk of cardiovascular disease in patients with type 1 diabetes.

  • The anti-inflammatory effects of fish oil may result from the inhibitory effects of oxidized omega-3 fatty acids on NF-B activation via a PPAR-dependent pathway (Art. Thromb. Vasc.Biol[2004]24:1621) Objective— The aim of this study was to determine the effects of oxidized versus native omega-3 fatty acids on the endothelial expression of chemokines MCP-1 and IL-8, and, if effective in inhibiting chemokine expression, to determine the mechanism for the inhibition of chemokine expression. Methods and Results— Using enzyme-linked immunosorbent assays, we show that oxidized EPA and DHA but not unoxidized EPA or DHA inhibit cytokine-induced endothelial expression of monocyte chemoattractant protein (MCP)-1 and, to a lesser extent, IL-8. In electrophoretic mobility shift assays, oxidized EPA but not unoxidized EPA potently inhibited cytokine-induced activation of endothelial nuclear factor-kappa-B (NF-kappaB). Using Western blot analyses, we show that the inhibition of NF-kappaB activation was not caused by prevention of phosphorylation of I-kappaB-alpha because oxidized EPA did not inhibit cytokine-induced phosphorylation and ubiquination of I-kappaB-alpha. Furthermore, oxidized EPA inhibited NF-kappaB activation in endothelial cells derived from wild-type mice but had no inhibitory effects on NF-kappaB activation in endothelial cells derived from peroxisome proliferator-activated receptor alpha (PPAR-alpha)-deficient mice, indicating that oxidized EPA requires PPAR-alpha for its inhibitory effects on NF-kappa-B. Conclusions— These studies show that the antiinflammatory effects of fish oil may result from the inhibitory effects of oxidized omega-3 fatty acids on NF-kappaB activation via a PPAR-alpha-dependent pathway.

  • Dietary omega-3 PUFAs provoke a hypocoagulant, vitamin K-independent effect in humans (Art. Thromb. Vasc.Biol[2004]24:1734) Objective— The beneficial effect of dietary fish oil, rich in omega-3 polyunsaturated fatty acids (PUFAs), on cardiovascular disease is multifactorial and may partly rely on their anticoagulant action. We studied how fish oil intake influenced thrombin generation in plasma and which factors were involved herein. Methods and Results— Twenty-five healthy males with borderline overweight received 3.0 g omega-3 PUFAs daily for 4 weeks. Fish oil intake reduced plasma triglycerides and lowered platelet integrin activation, as well as plasma levels of fibrinogen and factor V, but had no effect on vitamin K-dependent coagulation factors. Before fish oil intake, thrombin generation (reflecting the coagulant potential) considerably varied between plasmas from individual subjects, which were partly explained by variation in prothrombin, antithrombin, fibrinogen, and factor V levels. Fish oil intake reduced thrombin generation in the presence and absence of platelets. This reduction correlated with the fish oil effect on fibrinogen and factor V levels. Interestingly, the lowering effect of fish oil on thrombin generation and fibrinogen clustered around subjects with high fibrinogen carrying a structural fibrinogen alpha-chain polymorphism. Conclusions— Dietary omega-3 PUFAs provoke a hypocoagulant, vitamin K-independent effect in humans, the degree of which may depend on fibrinogen level. Intake of fish oil reduced fibrinogen and factor V levels as well as thrombin generation in plasma. The effects on thrombin generation and fibrinogen clustered around subjects with high fibrinogen carrying alpha-chain fibrinogen polymorphism. Thus, dietary fish oil can provoke a hypocoagulant effect depending on the fibrinogen level.

  • Rosuvastatin lowers LDL-C, apo B-100, apo-C-III, apo B100/apo A1 ratio and increases apo A-1 significantly better than gemfibrozil, but neither impact insulin sensitivity in patients with the [dys-]metabolic syndrome. (JACC [2005] 95, 189-193) To evaluate the pharmacologic intervention most likely to decrease cardiovascular disease risk in insulin-resistant patients with combined dyslipidemia, 39 patients with this abnormality were assessed before and after 3 months of treatment with gemfibrozil (1,200 mg/day) or rosuvastatin (40 mg/day) with regard to: (1) steady-state plasma glucose concentration at the end of a 180-minute infusion of octreotide, insulin, and glucose; (2) fasting lipid, lipoprotein, and apolipoprotein concentrations; and (3) daylong glucose, insulin, triglyceride, and remnant lipoprotein cholesterol concentrations in response to breakfast and lunch. The 2 groups were similar at baseline in age, gender, body mass index and in measurements of carbohydrate and lipoprotein metabolism. Neither gemfibrozil nor rosuvastatin enhanced insulin sensitivity or lowered daylong glucose and insulin concentrations in insulin-resistant patients with combined dyslipidemia, but both drugs significantly decreased fasting triglyceride concentrations. However, only rosuvastatin treatment significantly (p <0.05 to <0.001) reduced fasting low-density lipoprotein cholesterol, apolipoprotein B-100, apolipoprotein C-III, apolipoprotein C-III:B particles, the apolipoprotein B-100:apolipoprotein A-I ratio, and increased apolipoprotein A-I (p <0.05). The degree of improvement in fasting and postprandial remnant lipoprotein cholesterol concentrations was significantly greater (p <0.05) in rosuvastatin-treated patients, and this difference in the relative effectiveness of the drugs was also true of the decrease in non–high-density lipoprotein cholesterol concentrations.

  • Benefits of niacin by glycemic status in patients with healed myocardial infarction -from the Coronary Drug Project (Am J of Cardiol [2005] 95:254-257) The Coronary Drug Project, conducted during 1966 to 1974, was a randomized, double-blind, placebo-controlled trial of 5 lipid-modifying agents in 8,341 men with previous myocardial infarction.1 Among the 5 drug treatment regimens, only niacin significantly reduced the risk of (1) cardiovascular events during a mean follow-up of 6.2 years and (2) total mortality during 6.2 years with study treatment plus an additional 9 years of post-trial follow-up (Figure 1).2 and 3 Cardiovascular and total mortality outcomes in the niacin and placebo groups are presented by baseline glycemic status and by change in glycemic status from baseline to year 1.

  • ACE inhibition improves neovascularization in the diabetic ischemic leg through activation of bradykinin signaling, whereas it reduces vessel growth in the diabetic retina through inhibition of overacting Ang II pathway (Arterioscler Thromb Vasc Biol 2005;25 65-70) Objective— We analyzed the beneficial therapeutic effect of angiotensin converting enzyme inhibitor (ACEI) on both retinal and hind limb neovascularization in diabetic mice. Methods and Results— Diabetic mice (streptozotocin, 40 mg/kg) were treated with or without ACEI (Perindopril, 3 mg/kg per day) or AT1 receptor blocker (Candesartan, 20 mg/kg) for 4 months. Hind limb ischemia was then induced by right femoral artery ligature for 1 additional month. In the ischemic leg, angiographic score, capillary density, and foot perfusion were increased by 2.7, 2.0-fold, and 1.6-fold, respectively, in ACEI-treated diabetic mice compared with untreated diabetic animals (P<0.01). ACEI also raised vascular endothelial growth factor (VEGF) protein level by 1.4-fold in ischemic diabetic leg. This ACEI pro-angiogenic effect was totally blunted in diabetic bradykinin B2 receptor-deficient animals, suggesting that it was mediated by the bradykinin pathway. In the diabetic retina, angiotensinogen and ACE mRNA levels were increased by 2.8-fold and 4.1-fold, respectively (P<0.01 versus nondiabetic mice), highlighting a local activation of renin-angiotensin system. Diabetes also raised VEGF protein level by 1.5-fold (P<0.05 versus nondiabetic mice). Treatments with ACEI and AT1 receptor blocker hampered diabetes-induced VEGF upregulation and retinal neovascularization. Conclusion— ACE inhibition improved neovascularization in the diabetic ischemic leg through activation of bradykinin signaling, whereas it reduced vessel growth in the diabetic retina through inhibition of overacting Ang II pathway. ACE inhibition improved neovascularization in the diabetic ischemic leg through activation of bradykinin signaling, whereas it reduced vessel growth in the diabetic retina through inhibition of overacting Ang II pathway. ACEI may constitute a novel therapeutic strategy for the treatment of macrovascular and microvascular diseases in the setting of diabetes.

  • Only Within the Context of Multifactorial Intervention Might Glycemic Control Reduce CHD Events (Steno-2) (NEJM [2004] 348:383-393) Background Cardiovascular morbidity is a major burden in patients with type 2 diabetes. In the Steno-2 Study, we compared the effect of a targeted, intensified, multifactorial intervention with that of conventional treatment on modifiable risk factors for cardiovascular disease in patients with type 2 diabetes and microalbuminuria. Methods The primary end point of this open, parallel trial was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, revascularization, and amputation. Eighty patients were randomly assigned to receive conventional treatment in accordance with national guidelines and 80 to receive intensive treatment, with a stepwise implementation of behavior modification and pharmacologic therapy that targeted hyperglycemia, hypertension, dyslipidemia, and microalbuminuria, along with secondary prevention of cardiovascular disease with aspirin. Results The mean age of the patients was 55.1 years, and the mean follow-up was 7.8 years. The decline in glycosylated hemoglobin values, systolic and diastolic blood pressure, serum cholesterol and triglyceride levels measured after an overnight fast, and urinary albumin excretion rate were all significantly greater in the intensive-therapy group than in the conventional-therapy group. Patients receiving intensive therapy also had a significantly lower risk of cardiovascular disease (hazard ratio, 0.47; 95 percent confidence interval, 0.24 to 0.73), nephropathy (hazard ratio, 0.39; 95 percent confidence interval, 0.17 to 0.87), retinopathy (hazard ratio, 0.42; 95 percent confidence interval, 0.21 to 0.86), and autonomic neuropathy (hazard ratio, 0.37; 95 percent confidence interval, 0.18 to 0.79). ConclusionsA target-driven, long-term, intensified intervention aimed at multiple risk factors in patients with type 2 diabetes and microalbuminuria reduces the risk of cardiovascular and microvascular events by about 50 percent.

  • Insulin has an anti-inflammatory and profibrinolytic effect in patients with acute MI. These effects may contribute to the clinical benefits of insulin in STEMI (Circulation [2004]109:849-854.) Background— The clinical benefits of insulin previously observed in acute ST-segment–elevation myocardial infarction (STEMI) may be partially explained by an anti-inflammatory effect. We assessed this potential effect of insulin in STEMI patients treated with fibrinolytics. Methods and Results— Thirty-two patients receiving reteplase were randomly assigned infusions of either insulin at 2.5 U/h, dextrose, and potassium (GIK) or normal saline and potassium (C) for 48 hours. Plasma concentrations of high-sensitivity C-reactive protein (CRP), serum amyloid A (SAA), plasminogen activator inhibitor-1 (PAI-1), creatine kinase (CK), and CK-MB were measured at baseline and sequentially for 48 hours. Total p47phox protein in mononuclear cells was measured in a subgroup of 13 subjects. Baseline CRP and SAA were significantly increased (2- to 4-fold) at 24 and 48 hours in each group (P<0.01). However, in the insulin group, there was a significant (P<0.05) attenuation of the absolute rise in concentration of CRP and SAA from baseline. The absolute increase of CRP and SAA was reduced by 40% (CRP) and 50% (SAA) at 24 hours and at 48 hours compared with the control group. The absolute increase in PAI-1 from baseline and the percentage increase in p47phox over 48 hours were significantly (P<0.05) lower in the insulin-treated group. CK-MB peaked earlier and tended to be lower in insulin-treated subjects, especially in patients with inferior MI. Conclusions— Insulin has an anti-inflammatory and profibrinolytic effect in patients with acute MI. These effects may contribute to the clinical benefits of insulin in STEMI.
    Key Words: myocardial infarction • inflammation • insulin • atherosclerosis


  • Patients with ischemic cardiomyopathy benefit from early revascularization (Circulation [2003] 108:Suppl 1:II39-42) BACKGROUND: Patients with ischemic cardiomyopathy and viable myocardium may improve in function and prognosis following revascularization. Delayed revascularization may result in less favorable outcome, and therefore the impact of timing of revascularization on long-term outcome was evaluated. METHODS AND RESULTS: Patients (n=85) with ischemic cardiomyopathy and substantial viability (>or=25% of the left ventricle) on dobutamine stress echocardiography underwent surgical revascularization. Based on the waiting time for revascularization, patients were divided into 2 groups: early (<or=1 month) and late (>1 month) revascularization. Left ventricular ejection fraction (LVEF) was assessed before and 9 to 12 months after revascularization; follow-up data were acquired up to 2 years after revascularization. Hence, 40 patients underwent early (20+/-12 days) and 45 late (85+/-47 days) revascularization. Baseline characteristics of the two groups were comparable. Preoperative deaths were 0 in the early and 2 in the late group. Patients with early revascularization remained shorter time in the intensive care unit (2.4+/-1.5 days versus 5.9+/-2.1 days for the late group, P<0.05). Low output syndrome was observed more frequently in the late group (8% versus 22%, P=0.06). On long-term follow-up, mortality (5% versus 20%, P<0.05) and re-hospitalization for heart failure (10% versus 24%, NS) were higher in the late group. LVEF improved from 28+/-9% to 40+/-12% (P<0.05) in the early group and remained unchanged in the late group (27+/-10% versus 25+/-7%, NS). CONCLUSIONS: Patients with ischemic cardiomyopathy and viable myocardium benefit from early revascularization (with improvement in LVEF and favorable prognosis), whereas delayed revascularization of these patients is associated with worse outcome.

  • Acarbose reduces new HT by 5% and new CVD events by 2.5% in IGT (JAMA [2003] 290:486-494) Context  The worldwide explosive increase in type 2 diabetes mellitus and its cardiovascular morbidity are becoming major health concerns. Objective  To evaluate the effect of decreasing postprandial hyperglycemia with acarbose, an alpha-glucosidase inhibitor, on the risk of cardiovascular disease and hypertension in patients with impaired glucose tolerance (IGT). Design, Setting, and Participants  International, multicenter double-blind, placebo-controlled, randomized trial, undertaken in hospitals in Canada, Germany, Austria, Norway, Denmark, Sweden, Finland, Israel, and Spain from July 1998 through August 2001. A total of 1429 patients with IGT were randomized with 61 patients (4%) excluded because they did not have IGT or had no postrandomization data, leaving 1368 patients for a modified intent-to-treat analysis. Both men (49%) and women (51%) participated with a mean (SD) age of 54.5 (7.9) years and body mass index of 30.9 (4.2). These patients were followed up for a mean (SD) of 3.3 (1.2) years. Intervention  Patients with IGT were randomized to receive either placebo (n = 715) or 100 mg of acarbose 3 times a day (n = 714). Main Outcome Measures  The development of major cardiovascular events (coronary heart disease, cardiovascular death, congestive heart failure, cerebrovascular event, and peripheral vascular disease) and hypertension (>=140/90 mm Hg). Results  Three hundred forty-one patients (24%) discontinued their participation prematurely, 211 in the acarbose-treated group and 130 in the placebo group; these patients were also followed up for outcome parameters. Decreasing postprandial hyperglycemia with acarbose was associated with a 49% relative risk reduction in the development of cardiovascular events (hazard ratio [HR], 0.51; 95% confidence interval [CI]; 0.28-0.95; P = .03) and a 2.5% absolute risk reduction. Among cardiovascular events, the major reduction was in the risk of myocardial infarction (HR, 0.09; 95% CI, 0.01-0.72; P = .02). Acarbose was also associated with a 34% relative risk reduction in the incidence of new cases of hypertension (HR, 0.66; 95% CI, 0.49-0.89; P = .006) and a 5.3% absolute risk reduction. Even after adjusting for major risk factors, the reduction in the risk of cardiovascular events (HR, 0.47; 95% CI, 0.24-0.90; P = .02) and hypertension (HR, 0.62; 95% CI, 0.45-0.86; P = .004) associated with acarbose treatment was still statistically significant. Conclusion  This study suggests that treating IGT patients with acarbose is associated with a significant reduction in the risk of cardiovascular disease and hypertension.

  • OMA induces profound insulin sensitization and increases myocardial glucose uptake in Zucker fatty rats (Circulation [2003] 107:1923) Background— ACE inhibitors (ACEIs) improve insulin resistance and prevent type 2 diabetes, possibly mediated by inhibition of bradykinin (BK) degradation. The vasopeptidase inhibitor omapatrilat (OMA) raises BK to a greater extent than ACEIs by dual enzyme inhibition, whereas its insulin-sensitizing effects and mechanisms have not been investigated. Methods and Results— We compared the insulin-sensitizing effects of OMA, ramipril (an ACEI), losartan (an angiotensin II type 1 receptor blocker), and placebo by 2-step euglycemic hyperinsulinemic clamp in insulin-resistant Zucker fatty rats (n=6 to 7 in each group). OMA resulted in a lower rate of endogenous glucose production than placebo at baseline (35±5 versus 54±4 mmol · kg-1 · min-1, P<0.01), greater suppression of endogenous glucose production by low-dose insulin (73±11% versus 27±18%, P<0.05), and greater glucose disposal at high-dose insulin (135±5 versus 92±4 mmol · kg-1 · min-1, P<0.01). Ramipril tended to improve insulin sensitivity, but losartan did not. OMA significantly increased 2-deoxyglucose uptake by myocardium, fat, and skeletal muscle. Ramipril increased 2-deoxyglucose uptake only by some skeletal muscles, but losartan did not. The insulin-sensitizing effects of OMA were blocked significantly by HOE-140 (a BK, B2 receptor antagonist) and NG-nitro-L-arginine methyl ester (a nitric oxide synthase inhibitor) in all tissues except myocardium. Conclusions— OMA induces profound insulin sensitization and increases myocardial glucose uptake in Zucker fatty rats. This effect is greater than that of ramipril and probably occurs at least in part via stimulation of the B2 receptor. OMA has the potential for greater type 2 diabetes prevention than ACEI.

  • A higher consumption of fish and long-chain omega-3 fatty acids was associated with a lower CHD incidence and total mortality among diabetic women. (Circulation [2003] 107:1852) Background— Although several prospective cohort studies have found an inverse association between fish consumption and risk of coronary heart disease (CHD) or sudden cardiac death in the general population, limited data are available among diabetic patients. Methods and Results— We examined prospectively the association between intake of fish and omega-3 fatty acids and risk of CHD and total mortality among 5103 female nurses with diagnosed type 2 diabetes but free of cardiovascular disease or cancer at baseline. Between 1980 and 1996 (45 845 person-years of follow-up), we documented 362 incident cases of CHD (141 CHD deaths and 221 nonfatal myocardial infarctions) and 468 deaths from all causes. Compared with women who seldom consumed fish (<1 serving/mo), the relative risks (RRs) (95% CI) of CHD adjusted for age, smoking, and other established coronary risk factors were 0.70 (0.48 to 1.03) for fish consumption 1 to 3 times per month, 0.60 (0.42 to 0.85) for once per week, 0.64 (0.42 to 0.99) for 2 to 4 times per week, and 0.36 (0.20 to 0.66) for 5 or more times per week (P for trend=0.002). Higher consumption of fish was also associated with a significantly lower total mortality (multivariate RR=0.48 [0.29 to 0.80] for >=5 times per week [P for trend=0.005]). Higher consumption of long-chain omega-3 fatty acids was associated with a trend toward lower incidence of CHD (RR=0.69 [95% CI 0.47 to 1.03], P for trend=0.10) and total mortality (RR=0.63 [95% CI, 0.45 to 0.88], P for trend=0.02). Conclusions— A higher consumption of fish and long-chain omega-3 fatty acids was associated with a lower CHD incidence and total mortality among diabetic women.

  • Omega-3 fatty acid intake associates with reduced fatal, but not non-fatal, ischemic heart disease, consistent with possible antiarrhythmic effects (American Journal of Clinical Nutrition [2003] 77:319-325) Background: Little is known about the relation of the dietary intake of n-3 polyunsaturated fatty acids, ie, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from fatty fish and a-linolenic acid from vegetable oils, with ischemic heart disease among older adults. Objective: We investigated the associations of plasma phospholipid concentrations of DHA, EPA, and a-linolenic acid as biomarkers of intake with the risk of incident fatal ischemic heart disease and incident nonfatal myocardial infarction in older adults. Design: We conducted a case-control study nested in the Cardiovascular Health Study, a cohort study of adults aged >= 65 y. Cases experienced incident fatal myocardial infarction and other ischemic heart disease death (n = 54) and incident nonfatal myocardial infarction (n = 125). Matched controls were randomly selected (n = 179). We measured plasma phospholipid concentrations of n-3 polyunsaturated fatty acids in blood samples drawn ~2 y before the event. Results: A higher concentration of combined DHA and EPA was associated with a lower risk of fatal ischemic heart disease, and a higher concentration of a-linolenic acid with a tendency to lower risk, after adjustment for risk factors [odds ratio: 0.32 (95% CI: 0.13, 0.78; P = 0.01) and 0.52 (0.24, 1.15; P = 0.1), respectively]. In contrast, n-3 polyunsaturated fatty acids were not associated with nonfatal myocardial infarction. Conclusions: Higher combined dietary intake of DHA and EPA, and possibly a-linolenic acid, may lower the risk of fatal ischemic heart disease in older adults. The association of n-3 polyunsaturated fatty acids with fatal ischemic heart disease, but not with nonfatal myocardial infarction, is consistent with possible antiarrhythmic effects of these fatty acids.

  • C-type Natriuretic Peptide either releases or is Endothelium-Derived Hyperpolarization Factor
    (Proc. Natl. Acad. Sci. USA,[2003] 10.1073/pnas.0336365100)     Endothelial cells in most vascular beds release a factor that hyperpolarizes the underlying smooth muscle, produces vasodilatation, and plays a fundamental role in the regulation of local blood flow and systemic blood pressure. The identity of this endothelium-derived hyperpolarizing factor (EDHF), which is neither NO nor prostacyclin, remains obscure. Herein, we demonstrate that in mesenteric resistance arteries, release of C-type natriuretic peptide (CNP) accounts for the biological activity of EDHF. Both produce identical smooth muscle hyperpolarizations that are attenuated in the presence of high [K+], the Gi G protein (Gi) inhibitor pertussis toxin, the G protein-gated inwardly rectifying K+ channel inhibitor tertiapin, and a combination of Ba2+ (inwardly rectifying K+ channel blocker) plus ouabain (Na+/K+-ATPase inhibitor). Responses to EDHF and CNP are unaffected by the natriuretic peptide receptor (NPR)-A/B antagonist HS-142-1, but mimicked by the selective NPR-C agonist, cANF4-23. EDHF-dependent relaxation is concomitant with liberation of endothelial CNP; in the presence of the myoendothelial gap-junction inhibitor 18-alpha-glycyrrhetinic acid or after endothelial denudation, CNP release and EDHF responses are profoundly suppressed. These data demonstrate that acetylcholine-evoked release of endothelial CNP activates NPR-C on vascular smooth muscle that via a Gi coupling promotes Ba2+/ouabain-sensitive hyperpolarization. Thus, we have revealed the identity of EDHF and established a pivotal role for endothelial-derived CNP in the regulation of vascular tone and blood flow.

  • Adiponectin Reduces Atherosclerosis in Apolipoprothhein E-Deficient Mice (Circulation. (2002)106:2767) Background— Dysregulation of adipocyte-derived bioactive molecules plays an important role in the development of atherosclerosis. We previously reported that adiponectin, an adipocyte-specific plasma protein, accumulated in the injured artery from the plasma and suppressed endothelial inflammatory response and vascular smooth muscle cell proliferation, as well as macrophage-to-foam cell transformation in vitro. The current study investigated whether the increased plasma adiponectin could actually reduce atherosclerosis in vivo. Methods and Results— Apolipoprotein E-deficient mice were treated with recombinant adenovirus expressing human adiponectin (Ad-APN) or ß-galactosidase (Ad-ßgal). The plasma adiponectin levels in Ad-APN–treated mice increased 48 times as much as those in Ad-ßgal treated mice. On the 14th day after injection, the lesion formation in aortic sinus was inhibited in Ad-APN–treated mice by 30% compared with Ad-ßgal–treated mice (P<0.05). In the lesions of Ad-APN–treated mice, the lipid droplets became smaller compared with Ad-ßgal–treated mice (P<0.01). Immunohistochemical analyses demonstrated that the adenovirus-mediated adiponectin migrate to foam cells in the fatty streak lesions. The real-time quantitative polymerase chain reaction revealed that Ad-APN treatment significantly suppressed the mRNA levels of vascular cell adhesion molecule-1 by 29% and class A scavenger receptor by 34%, and tended to reduce levels of tumor necrosis factor-{alpha} without affecting those of CD36 in the aortic tissue. Conclusions— These findings documented for the first time that elevated plasma adiponectin suppresses the development of atherosclerosis in vivo.

  • Insulin Reduces Progression of Carotid Stenosis in Type 2 Diabetes Mellitus: A Three Years Prospective Study. Francesco N Piarulli, Geriatric, Padova, Italy; Giuseppe S Bax, Maria Elena A Marolla, Fedele D Domenico, Diabetes Clinics, Padova, Italy (Circulation (2002) 106(#19):II-442) Diabetes Mellitus (DM) represents a strong risk factor for stroke. The Bruneck Study demonstrated the independent role of DM on progression of Carotid Stenosis (CS). A prospective study was made to evaluate the evolution of CS in 87 Type 2 DM patients(DMP). The clinical characteristics and risk profile ( age, BMI, years of DM, HbA1c, microalbuminuria, hypoglycemic therapy (diet"D","ADO", Insulin"I"), lipid profile, smoke, hypertension, use of antihypertensive, antiplatelets and statins, history of peripheral and/or coronary artery disease, previous stroke/TIA ) were checked at baseline. At baseline and 3 years later CS was determined by Ultrasound Score (US) : grade 1 until (>) 20 % CS, grade 2 > 50 % CS, grade 3 > 75 % CS, grade 4 > 99 % CS, grade 5 = occlusion, according to Streadness criteria. Results: The distribution of CS-US at baseline was: 29 DMP (33.3 %) grade 1, 40 DMP (45.6 %) grade 2, 10 DMP (11.5 %) grade 3, 7 DMP ( 8 %) grade 5 ( this last group was eliminated from follow-up). Stabilization (S) of CS was estimated in 59 DMP ( 74.7 %), whereas progression (P) in 20 DMP (25.3 %). Multivariate logistic regression analysis found only two variables associated with probability of P of CS : hypoglycemic therapies (HT) and HbA1c. There is an inverse relation between HT and P of CS ("D" is more strongly associated than "I"). In conclusion , Type 2 DMP in dietary treatment have a risk P of CS 5 times more than DMP who used oral Hypoglycemic drugs . Moreover, the insulin treatment reduced the progression of carotid stenosis 5 times more than DMP who take oral hypoglycemic drugs . The association between P and HbA1c is positive: the risk of P increases by 90 % for every point increase of HbA1c.

  • A diet rich in fish associates with lower plasma leptin levels which might help to explain reduced cardiovascular risk seen with high-fish diets. (Circulation [2002] 10.1161/01.CIR.0000025241.01418.4D)Background—Leptin has been implicated in cardiovascular disease. A diet rich in fish has been associated with decreased cardiac and vascular risk.Methods and Results—We examined the relationship between diet and leptin in 2 related homogeneous African tribal populations of Tanzania. One tribe consumes freshwater fish as their main diet component (n=279), and the other tribe consumes a primarily vegetarian diet (n=329). In multivariate analysis, plasma leptin levels were associated with type of diet (F=14.3, P<0.001), independent of age, body mass index, body fat, alcohol consumption, or insulin. Both male (2.5±2 [fish diet] versus 11.2±2.4 [vegetarian diet] ng/mL, P=0.017) and female (5.0±1.9 [fish diet] versus 11.8±1.4 [vegetarian diet] ng/mL, P=0.007) fish eaters had lower plasma leptin levels than did their vegetable diet counterparts, even though body mass index values were virtually identical. Conclusions—A diet rich in fish is associated with lower plasma leptin, independent of body fat. These findings may have implications for understanding the reduced cardiovascular risk in subjects on a high-fish diet.
  • Atorvastatin Lowers CRP in Dyslipidemic Patients, Bezafibrate Does Not (Atherosclerosis [2002] 162:245-251)C-reactive protein (CRP) is a non-specific but sensitive marker of underlying systemic inflammation. High CRP plasma levels correlate with risk for future cardiovascular events. The present study evaluated the effects of atorvastatin (10¯40 mg) and bezafibrate (400 mg) on CRP concentrations after 6 and 12 months of treatment in 103 patients with combined (mixed) hyperlipidemia. The number of cardiovascular risk factors present in a given patient was associated with baseline CRP levels. After 6 months and 1 year, atorvastatin treatment was associated with significant (P<0.001) decreases from baseline of CRP concentrations by 29 and 43%, respectively, while bezafibrate-treated patients showed non-significant reductions of 2.3 and 14.6%, respectively (P=0.056 and 0.005 for the respective differences between the two treatment arms at 6 months and 1 year). The magnitude of change in CRP after 1 year was directly related to baseline CRP levels. Covariance analysis showed that CRP decreases in the atorvastatin group were unrelated to total cholesterol and LDL cholesterol reductions; however, they were directly related to triglyceride changes (r=0.28, P=0.047) and inversely related to HDL cholesterol changes (r=-0.28, P=0.045). A model including baseline CRP values and treatment effect showed that atorvastatin use was a significant predictor of change in CRP levels over time (=0.82, P=0.023). These results suggest a potential anti-atherosclerotic additional benefit of atorvastatin in patients at a risk of cardiovascular disease.
  • Statins protect CHD patients with elevated C-RP from excess mortality (The American Journal of Cardiology [2002]89(8):901-908) We evaluated a possible interaction between statins and inflammation in 1,246 patients with angiographically diagnosed coronary artery disease. Four different inflammatory markers were determined: high, sensitive C-reactive protein (hs-CRP) (p = 0.001), fibrinogen (p = 0.006), von Willebrand factor (p = 0.006), and leukocyte count (p = 0.03); these levels were significantly higher among the 88 patients who died of cardiac causes during follow-up (median 2.9 years) than among survivors. In a multivariate backward stepwise Cox regression mode, only hs-CRP was evaluated to be a significant predictor of death from coronary artery disease. This prediction was lost in statin-treated patients. Compared with patients receiving statin medication, patients without statins did not have increased cardiac mortality (even when low-density lipoprotein [LDL] levels were >125 mg/dl) when hs-CRP levels were not elevated. In contrast, patients without statins and elevated hs-CRP (top quartile) had a 2.3-fold increase in risk for fatal coronary events, independent of LDL levels. In conclusion, only elevated hs-CRP was selected as an independent predictor of death. Statin therapy is associated with elevated hs-CRP, with a risk reduction for fatal coronary events, independent of LDL levels; this, in part, may be explained by the anti-inflammatory effects on atherosclerosis.
  • Statin Prevents Thrombin-Induced Tissue Factor Expression in Human Endothelial Cells via Inhibition of Rho/Rho-Kinase and Activation of Akt (Circulation [2002] 105(15):1756) Background— Tissue factor plays a pivotal role in thrombus formation in acute coronary syndromes. However, the regulatory mechanisms underlying tissue factor expression are poorly understood. Statins are effective in patients with acute coronary syndromes. Hence, the aim of this study was to clarify in human endothelial cells the signaling pathways of thrombin-induced tissue factor expression and potential inhibitory effects of statins. Methods and Results— In human aortic endothelial cells, simvastatin prevented tissue factor induction by thrombin (4 U/mL) in a concentration-dependent manner. The increase in tissue factor activity on the cell surface was also blocked by simvastatin. Simvastatin also prevented the upregulation of tissue factor expression and activity in human aortic smooth muscle cells. Mevalonate (100 µmol/L) reversed the inhibitory effect of simvastatin on tissue factor expression. Thrombin induced rapid activation of Rho A and p38 MAP kinase. The Rho-kinase inhibitor Y-27632 and the p38 MAP kinase inhibitor SB203580 prevented tissue factor induction. Akt was dephosphorylated by thrombin; the phosphoinositol 3-kinase inhibitor wortmannin enhanced its dephosphorylation as well as thrombin-induced tissue factor expression. Simvastatin prevented thrombin-induced Rho A activation but not p38 MAP kinase activation. Akt dephosphorylation by thrombin was blocked by both simvastatin and Y-27632. Conclusions— Endothelial tissue factor induction by thrombin is regulated by Rho/Rho-kinase, Akt, and p38 MAP kinase. Simvastatin prevents its induction through inhibition of Rho/Rho-kinase and activation of Akt. These findings provide new insights into the action of statins in acute coronary syndromes
  • Three Studies Show Benefits Of Fish Oil On Heart Health (IntelliHealth April [2002]) Heart-attack survivors who took fish-oil supplements in a study had only half the level of sudden cardiac death within the first four months of treatment as those who did not get the supplements. Results, published in Circulation, a journal of the American Heart Association, came from an Italian heart-disease-prevention study with 11,000 participants.
  • The n–3 fatty acids found in fish are strongly associated with a reduced risk of sudden death among men without evidence of prior cardiovascular disease.(NEJM [2002]346:1113-1118) Background Experimental data suggest that long-chain n–3 polyunsaturated fatty acids found in fish have antiarrhythmic properties, and a randomized trial suggested that dietary supplements of n–3 fatty acids may reduce the risk of sudden death among survivors of myocardial infarction. Whether long-chain n–3 fatty acids are also associated with the risk of sudden death in those without a history of cardiovascular disease is unknown. Methods We conducted a prospective, nested case–control analysis among apparently healthy men who were followed for up to 17 years in the Physicians' Health Study. The fatty-acid composition of previously collected blood was analyzed by gas–liquid chromatography for 94 men in whom sudden death occurred as the first manifestation of cardiovascular disease and for 184 controls matched with them for age and smoking status. Results Base-line blood levels of long-chain n–3 fatty acids were inversely related to the risk of sudden death both before adjustment for potential confounders (P for trend = 0.004) and after such adjustment (P for trend = 0.007). As compared with men whose blood levels of long-chain n–3 fatty acids were in the lowest quartile, the relative risk of sudden death was significantly lower among men with levels in the third quartile (adjusted relative risk, 0.28; 95 percent confidence interval, 0.09 to 0.87) and the fourth quartile (adjusted relative risk, 0.19; 95 percent confidence interval, 0.05 to 0.71). Conclusions The n–3 fatty acids found in fish are strongly associated with a reduced risk of sudden death among men without evidence of prior cardiovascular disease.
  • Among women, higher consumption of fish and omega-3 fatty acids is associated with a lower risk of CHD, particularly CHD deaths (JAMA [2002] 287:1815-1821) Context  Higher consumption of fish and omega-3 fatty acids has been associated with a lower risk of coronary heart disease (CHD) in men, but limited data are available regarding women.Objective  To examine the association between fish and long-chain omega-3 fatty acid consumption and risk of CHD in women.Design, Setting, and Participants  Dietary consumption and follow-up data from 84 688 female nurses enrolled in the Nurses' Health Study, aged 34 to 59 years and free from cardiovascular disease and cancer at baseline in 1980, were compared from validated questionnaires completed in 1980, 1984, 1986, 1990, and 1994.Main Outcome Measures  Incident nonfatal myocardial infarction and CHD deaths.Results  During 16 years of follow-up, there were 1513 incident cases of CHD (484 CHD deaths and 1029 nonfatal myocardial infarctions). Compared with women who rarely ate fish (<1 per month), those with a higher intake of fish had a lower risk of CHD. After adjustment for age, smoking, and other cardiovascular risk factors, the multivariable relative risks (RRs) of CHD were 0.79 (95% confidence interval [CI], 0.64-0.97) for fish consumption 1 to 3 times per month, 0.71 (95% CI, 0.58-0.87) for once per week, 0.69 (95% CI, 0.55-0.88) for 2 to 4 times per week, and 0.66 (95% CI, 0.50-0.89) for 5 or more times per week (P for trend = .001). Similarly, women with a higher intake of omega-3 fatty acids had a lower risk of CHD, with multivariable RRs of 1.0, 0.93, 0.78, 0.68, and 0.67 (P<.001 for trend) across quintiles of intake. For fish intake and omega-3 fatty acids, the inverse association appeared to be stronger for CHD deaths (multivariate RR for fish consumption 5 times per week, 0.55 [95% CI, 0.33-0.90] for CHD deaths vs 0.73 [0.51-1.04]) than for nonfatal myocardial infarction. Conclusion  Among women, higher consumption of fish and omega-3 fatty acids is associated with a lower risk of CHD, particularly CHD deaths.
  • Among patients with CHD who have low LDL-C, Pravastatin reduces the event rate in diabetics to that of nondiabetic participants.(Circulation. [2002] 105:1424.)
    Background— In two large secondary prevention trials of pravastatin, risk reduction was not significant in participants who had low baseline LDL-C concentrations (that is, <125 mg/dL). We conducted exploratory analyses of participant characteristics, lipid risk factors, and risk reduction in this group.Methods and Results— Among 13 173 participants with coronary heart disease (CHD), 2607 had baseline LDL-C <125 mg/dL. Those with LDL-C <125 compared with >=125 mg/dL were more likely to be diabetic (15% versus 9%), hypertensive (46 versus 41%), and male (89% versus 83%); they had higher triglycerides (169 versus 154 mg/dL), lower HDL-C (36.5 versus 38 mg/dL), and similar body mass index (27 kg/m2); and pravastatin lowered their LDL-C by 36 mg/dL (32%) versus 45 mg/dL (29%). During 5.8-year (mean) follow-up, HDL-C and triglycerides were both significantly stronger predictors of recurrent CHD events in participants with LDL-C <125 than >=125 mg/dL. In diabetic participants with low LDL-C, pravastatin decreased CHD events from 34% to 22% (relative risk, 0.56; 95% CI, 0.37 to 0.83; P=0.004), significantly different from the effect in nondiabetic participants with low LDL-C (P interaction, 0.005) (event rate, 21%; relative risk, 1.06 [95% CI, 0.89 to 1.27]). There were trends toward risk reduction in smokers and in those with low HDL-C, <40 mg/dL. Conclusions— Among patients with CHD who have low LDL-C, diabetics have much higher subsequent CHD event rates than do nondiabetics. Pravastatin reduced the event rate in diabetics to that of nondiabetic participants. The results also suggest enhanced therapeutic potential for improving HDL-C and triglycerides in patients with CHD who have low LDL-C concentrations.
  • In vivo administration of insulin activates Akt through the PI3-kinase–dependent mechanism and reduces postischemic myocardial apoptotic death (Circulation. [2002] 105:1497.) Background— Recent evidence from cultured endothelial cell studies suggests that phosphorylation of endothelial nitric oxide synthase (eNOS) through the PI3-kinase–Akt pathway increases NO production. This study was designed to elucidate the signaling pathway involved in the antiapoptotic effect of insulin in vivo and to test the hypothesis that phosphorylation of eNOS by insulin may participate in the cardioprotective effect of insulin after myocardial ischemia and reperfusion.Methods and Results— Male Sprague-Dawley rats were subjected to 30 minutes of myocardial ischemia and 4 hours of reperfusion. Rats were randomized to receive vehicle, insulin, insulin plus wortmannin, or insulin plus L-NAME. Treatment with insulin resulted in 2.6-fold and 4.3-fold increases in Akt and eNOS phosphorylation and a significant increase in NO production in ischemic/reperfused myocardial tissue. Phosphorylation of Akt and eNOS and increase of NO production by insulin were completely blocked by wortmannin, a PI3-kinase inhibitor. Pretreatment with L-NAME, a nonselective NOS inhibitor, had no effect on Akt and eNOS phosphorylation but significantly reduced NO production. Moreover, treatment with insulin markedly reduced myocardial apoptotic death (P<0.01 versus vehicle). Pretreatment with wortmannin abolished the antiapoptotic effect of insulin. Most importantly, pretreatment with L-NAME also significantly reduced the antiapoptotic effect of insulin (P<0.01 versus insulin)Conclusions— These results demonstrated that in vivo administration of insulin activated Akt through the PI3-kinase–dependent mechanism and reduced postischemic myocardial apoptotic death. Phosphorylation of eNOS and the concurrent increase of NO production contribute significantly to the antiapoptotic effect of insulin.
  • Bisphosphonates may have anti-atherosclerotic properties (Vascular Pharmacology [2002] 35: 287-296) Bisphosphonates are used for the treatment of bone resorption, hypercalcemia, osteoporosis and Paget's disease. Etidronate, pamidronate and clodronate also inhibit the development of experimental atherosclerosis without altering serum lipid profile. Bisphosphonates inhibit the arterial calcification, lipid accumulation and fibrosis. They accumulate extensively in arterial walls and suppress macrophages in atheromatous lesions. In macrophage cultures, bisphosphonates inhibit the cellular accumulation and degradation of atherogenic LDL-cholesterol and foam cell formation. Further, they inhibit various enzymes involved in cell signal transduction and cholesterol biosynthesis. Recently, etidronate has been shown to inhibit the thickening of carotid arterial wall even in man.
  • Increased circulating level of Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) may be an important causative factor of hypofibrinolysis in patients with type 2 diabetes, obesity and insulin resistance (The Journal of Clinical Endocrinology & Metabolism [2002] 87: 660-665) Hypofibrinolysis is a common finding in patients with diabetes mellitus (DM) and obesity and a risk factor for the development of cardiovascular disease. Recently, a new potent inhibitor of fibrinolysis, the thrombin-activatable fibrinolysis inhibitor (TAFI) has been isolated and characterized from human plasma. The present study was undertaken to assess the activity and circulating level of TAFI and its relation to fibrinolytic function and obesity in patients with type 2 DM. Fifty-seven patients with type 2 DM (38 men, 19 women) were enrolled in this study. DM patients were categorized in age-matched obese [body mass index (BMI) >= 25] and nonobese (BMI < 25) groups. The plasma concentration and activity of TAFI were significantly (P < 0.05) higher in DM patients than in healthy controls. The plasma levels and activity of TAFI were significantly (P < 0.05) elevated in obese DM patients compared with nonobese DM and nonobese healthy subjects. RT-PCR demonstrated the expression of TAFI in human adipose tissue and in human endothelial cells. The plasma levels of TAFI were independently and significantly correlated with glucose intolerance (HbA1c), with obesity (BMI, visceral fat area), and with an indicator of insulin resistance (glucose infusion rate). This study showed that increased circulating level of TAFI may be an important causative factor of hypofibrinolysis in patients with type 2 diabetes, obesity and insulin resistance.
  • Atorvastatin Lowers C-Reactive Protein and Improves Endothelium-Dependent Vasodilation in Type 2 Diabetes Mellitus (The Journal of Clinical Endocrinology & Metabolism [2002] 87: 563-568) Endothelial dysfunction is frequently found in diabetic subjects. This study was performed to investigate whether atorvastatin therapy was able to reverse endothelial dysfunction in typediabetes and, if so, whether the effect was due to 2 its antiinflammatory (baseline low density lipoprotein, 4.37 ± action. Eighty patients 0.71 mmol/liter) were randomized to atorvastatin (10 mg daily for 3 months, followed by 20 mg daily for 3 months) or placebo in a double blind study. Endothelial function wasresolution vascular ultrasound, and high assessed by high sensitivityassessed by immunoturbidimetric assay. C-reactive protein (CRP) was Diabetic patients had higher CRP (than matched nondiabetic controls, P < 0.01) and both endothelium-dependent and independent vasodilation were impaired (P < 0.01). Atorvastatin (10 and 20 mg) lowered plasma cholesterol by 32.9% and 38.0%, triglyceride15.4% and 23.1%, and low density lipoprotein by 43.4% by andplasma CRP decreased in the atorvastatin 50.1%, respectively. At 6 months, group compared with baseline (P < 0.05). Endothelium-dependent vasodilation improved in the atorvastatin group compared with the placebo group (P < 0.05). The percent change in endothelium-dependent vasodilation at 6 months correlated with the percent change-0.44; P < 0.05), but not with changes in in CRP (r = plasmalipids. In conclusion, treatment with atorvastatin in type 2 diabetes led to a significant improvement in endothelium-dependent vasodilation, which might be partly related to its anti-inflammatory effect.
  • Angptl3 probably regulates lipid metabolism in animals (Nature Genetics [2002] 30:151-157) The KK obese mouse is moderately obese and has abnormally high levels of plasma insulin (hyperinsulinemia), glucose (hyperglycemia) and lipids (hyperlipidemia). In one strain (KK/San), we observed abnormally low plasma lipid levels (hypolipidemia). This mutant phenotype is inherited recessively as a mendelian trait. Here we report the mapping of the hypolipidemia (hypl) locus to the middle of chromosome 4 and positional cloning of the autosomal recessive mutation responsible for the hypolipidemia. The hypl locus encodes a unique angiopoietin-like lipoprotein modulator, which we named Allm1. It is identical to angiopoietin-like protein 3, encoded by Angptl3, and has a highly conserved counterpart in humans. Overexpression of Angptl3 or intravenous injection of the purified protein in KK/San mice elicited an increase in circulating plasma lipid levels. This increase was also observed in C57BL/6J normal mice. Taken together, these data suggest that Angptl3 regulates lipid metabolism in animals.
  • Oral Administration of an Apo A-I Mimetic Peptide Synthesized From D-Amino Acids Dramatically Reduces Atherosclerosis in Mice Independent of Plasma Cholesterol (Circulation [2002]105:290) When apolipoprotein A-I mimetic peptides synthesized from either D- or L-amino acids were given orally to LDL receptor-null mice, only the peptide synthesized from D-amino acids was stable in the circulation and enhanced the ability of HDL to protect LDL against oxidation. The peptide synthesized from L-amino acids was rapidly degraded and excreted in the urine. When a peptide synthesized from D-amino acids (D-4F) was administered orally to LDL receptor-null mice on a Western diet, lesions decreased by 79%. When added to the drinking water of apoE-null mice, D-4F decreased lesions by approximately 75% at the lowest dose tested (0.05 mg/mL). The marked reduction in lesions occurred independent of changes in total plasma or HDL-cholesterol.

  • In obese women, endothelial activation correlates with visceral body fat and weight loss represents a safe method for downregulating the inflammatory state and ameliorating endothelial dysfunction. (Circulation [2002; 10:1161)

    Background—Visceral fat is a key regulator site for the process of inflammation, and atherosclerotic lesions are essentially an inflammatory response.Methods and Results—Fifty-six healthy premenopausal obese women (age range 25 to 44 years, body mass index 37.2±2.2, waist to hip ratio range 0.78 to 0.92) and 40 age-matched normal weight women were studied. Compared with nonobese women, obese women had increased basal concentrations of tumor necrosis factor-alpha (TNF-alpha, P<0.01), interleukin-6 (IL-6, P<0.01), P-selectin (P<0.01), intercellular adhesion molecule-1 (ICAM-1, P<0.02), and vascular adhesion molecule-1 (VCAM-1, P<0.05). Vascular responses to L-arginine (3 g IV), the natural precursor of nitric oxide, were impaired in obese women: reductions in mean blood pressure (P<0.02), platelet aggregation to adenosine diphosphate (P<0.05), and blood viscosity (P<0.05) were significantly lower as compared with those in the nonobese group. Concentrations of TNF-alphaand IL-6 were related (P<0.01) to visceral obesity, as well as to adhesin levels and responses to L-arginine. After 1 year of a multidisciplinary program of weight reduction (diet, exercise, behavioral counseling), all obese women lost at least 10% of their original weight (9.8±1.5 kg, range 7.5 to 13 kg). Compared with baseline, sustained weight loss was associated with reduction of cytokine (P<0.01) and adhesin (P<0.02) concentrations and with improvement of vascular responses to L-arginine.Conclusion—In obese women, endothelial activation correlates with visceral body fat, possibly through inappropriate secretion of cytokines. Weight loss represents a safe method for downregulating the inflammatory state and ameliorating endothelial dysfunction in obese women.

  • Estrogen Monotherapy Reduces Risk of Carotid IMT - and Improves Glucose Control (Ann Intern Med. [2001] 135:939-953) Background: Although observational studies suggest that estrogen replacement therapy (ERT) reduces cardiovascular morbidity and mortality in postmenopausal women, use of unopposed ERT for prevention of coronary heart disease in healthy postmenopausal women remains untested.Objective:  To determine the effects of unopposed ERT on the progression of subclinical atherosclerosis in healthy postmenopausal women without preexisting cardiovascular disease.Design: Randomized, double-blind, placebo-controlled trial.Setting:University-based clinic. Patients:  222 postmenopausal women 45 years of age or older without preexisting cardiovascular disease and with low-density lipoprotein cholesterol levels of 3.37 mmol/L or greater (130 mg/dL). Intervention: Unopposed micronized 17beta-estradiol (1 mg/d) or placebo. All women received dietary counseling. Women received lipid-lowering medication if their low-density lipoprotein cholesterol level exceeded 4.15 mmol/L (160 mg/dL).Measurements:  The rate of change in intima–media thickness of the right distal common carotid artery far wall in computer image processed B-mode ultrasonograms obtained at baseline and every 6 months during the 2-year trial. Results: In a multivariable mixed-effects model, among women who had at least one follow-up measurement of carotid intima–media thickness (n = 199), the average rate of progression of subclinical atherosclerosis was lower in those taking unopposed estradiol than in those taking placebo (0.0017 mm/y vs. 0.0036 mm/y); the placebo–estradiol difference between average progression rates was 0.0053 mm/y (95% CI, 0.0001 to 0.0105 mm/y) (P = 0.046). Among women who did not receive lipid-lowering medication (n = 77), the placebo–estradiol difference between average rates of progression was 0.0147 mm/y (CI, 0.0055 to 0.0240) (P = 0.002). Average rates of progression did not differ between estradiol and placebo recipients who took lipid-lowering medication (n = 122) (P > 0.2). The placebo group increased HbA1c by 1.6 ± 0.6% (n=89) whereas the estradiol group decreased their HbA1c by 0.8 ± 0.6% (n=90) (p<0.007) Despite worsened control, the placebo group decreased insulin levels by 3.7 ± 2.9% whereas despite improved control the estradiol group decreased insulin levels by 14.0 ± 2.9% (n=90) (p<0.01). (Conclusions:  Overall, the average rate of progression of subclinical atherosclerosis was slower in healthy postmenopausal women taking unopposed ERT with 17beta-estradiol than in women taking placebo. Reduction in the progression of subclinical atherosclerosis was seen in women who did not take lipid-lowering medication but not in those who took these medications.

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