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Query: UMLS:C0038454 (stroke)
147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Troglitazone is a thiazolidinedione under development for the treatment of NIDDM and potentially other insulin-resistant disease states. Treatment with troglitazone is associated with an improvement in hyperglycemia, hyperinsulinemia, and insulin-mediated glucose disposal. No significant side effects have been observed in humans. Because of reported cardiac changes in animals treated with drugs of this class, this multicenter 48-week study was conducted to evaluate whether NIDDM patients treated with troglitazone develop any cardiac mass increase or functional impairment. A total of 154 NIDDM patients were randomized to receive troglitazone 800 mg q.d. or glyburide titrated to achieve glycemic control (< or =20 mg b.i.d. or q.d.). Two-dimensional echocardiography and pulsed Doppler were used to measure left ventricular mass index (LVMI), cardiac index (CI), and stroke volume index (SVI). All echocardiograms were performed at each center (baseline, 12, 24, 36, and 48 weeks), recorded on videotape, and forwarded to a blinded central echocardiographic interpreter for analysis. The results showed that LVMI of patients treated with troglitazone was not statistically or clinically different from baseline after 24 or 48 weeks. Statistically significant increases in SVI and CI and a statistically significant decrease in diastolic pressure and estimated peripheral resistance were observed in troglitazone-treated patients. These results were not sex-specific. Glycemic benefits of troglitazone treatment were observed as evidenced by long-term improvement of HbA1c and C-peptide levels. Furthermore, triglycerides were significantly lower, and HDL was significantly higher at weeks 24 and 48. In conclusion, NIDDM patients treated with troglitazone do not show any cardiac mass increase or cardiac function impairment. Conversely, patients on troglitazone benefited from enhanced cardiac output and stroke volume, possibly as a result of decreased peripheral resistance. Treatment with troglitazone appears to have a favorable impact on known cardiovascular risk factors and could potentially lower cardiovascular morbidity in NIDDM patients.
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PMID:Cardiac and glycemic benefits of troglitazone treatment in NIDDM. The Troglitazone Study Group. 903 99

Troglitazone is a thiazolidinedione used for the treatment of NIDDM and potentially for other insulin-resistant disease states. Troglitazone has recently been shown to increase cardiac output and stroke volume in human subjects. These actions are thought to be mediated by the reduction of peripheral resistance, but a potential direct effect on cardiac function has not been studied. Therefore, we investigated the direct cardiac hemodynamic effects of troglitazone in isolated perfused rat hearts. Five groups of hearts were studied. Hearts were tested under isovolumetric contraction with a constant coronary flow, and troglitazone (0.2, 0.5, and 1.0 micromol) was administered by bolus injection. Peak isovolumetric left ventricular pressure (LVPmax), peak rate of rise of LVP (dP/dt(max)), and peak rate of fall of LVP (dP/dt(min)) were significantly increased 1 min after troglitazone administration in a dose-dependent manner, while the heart rate (HR) and coronary perfusion pressure (CPP) were significantly decreased (P < 0.05). HR was then fixed by pacing and/or CPP was fixed with nitroprusside to eliminate any effect of the two variables on the action of troglitazone. With constant HR and/or constant CPP, the effect of troglitazone on LVPmax, dP/dt(max), and dP/dt(min) was still unchanged. In addition, the positive inotropic, positive lusitropic, and negative chronotropic actions of troglitazone were not influenced even when hearts were pretreated with prazosin, propranolol, or nifedipine. In conclusion, troglitazone has direct positive inotropic, positive lusitropic, negative chronotropic, and coronary artery dilating effects. The inotropic and chronotropic actions of troglitazone are not mediated via adrenergic receptors or calcium channels. These findings have important clinical implications for diabetic patients with congestive heart failure.
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PMID:Hemodynamic basis for the acute cardiac effects of troglitazone in isolated perfused rat hearts. 1007 64

The present study examined the hemodynamic mechanisms of blood pressure (BP) lowering by troglitazone in patients with type 2 diabetes mellitus (DM) at rest and during a mental arithmetic test (MAT). Twenty-two patients with DM with normal to high-normal BP and 12 controls matched for age, gender, glucose tolerance, and BP were studied. DM subjects showed significantly higher systolic BP response during MAT than controls (157 versus 139 mm Hg; P<0.01). All 22 DM patients and 5 of 12 controls had systolic BP >140 mm Hg during MAT. Heart rate and diastolic BP were not significantly different between the 2 groups. The DM group was then randomized to receive troglitazone (n=10; 400 mg/d) or glyburide (n=12; 20 mg/d). MAT was repeated after 6 months of treatment. Both treatments reduced glucose equally (-1.7 mmol/L for troglitazone and -1.5 mmol/L for glyburide), but only troglitazone reduced insulin (-15 microU/mL; P<0.001) and C-peptide (-0.9 ng/mL; P<0.02) levels. Troglitazone significantly reduced BP at baseline (P<0.05) and systolic BP response to MAT (P<0.01), whereas glyburide did not affect BP at baseline or during MAT. Stroke volume and cardiac output did not change with either drug, but troglitazone decreased peripheral vascular resistance (-112 dyne. s. cm(-5); P<0.05). Improved insulin resistance rather than an improved glycemic control is associated with lower resting and stress BP values in patients with DM. A reduction in vascular resistance may be a primary hemodynamic mechanism of the manner in which troglitazone lowers BP. Insulin sensitizers may offer potential therapeutic advantage in subjects with DM with elevated BP.
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PMID:Vasodilatory effects of troglitazone improve blood pressure at rest and during mental stress in type 2 diabetes mellitus. 1040 28

Troglitazone increased cardiac output and stroke volume, as a result of decreased peripheral resistance, in diabetic patients with normal cardiac function. The cardiovascular effects of troglitazone in patients with heart failure are unknown. The aim of the study was to evaluate the cardiovascular effects of troglitazone in patients with heart failure. Blood pressure and echocardiographic findings were evaluated before and 1, 2, 3 and 4 hours after a single dose of troglitazone (400 mg) or placebo, in eight type II diabetic patients with congestive heart failure. The plasma catecholamines and coefficient of variance of RR intervals (CVRR) were also measured. Neither heart rate nor blood pressure changed after the administration of troglitazone. Left ventricular (LV) end-diastolic dimension did not change either, however, the LV end-systolic dimension significantly decreased compared with its baseline value and with that of the placebo group. On the other hand, the % fractional shortening and the E/A ratio increased significantly after troglitazone. The LV end-diastolic volume did not change, whereas the LV end-systolic volume significantly decreased. The stroke volume and the LV ejection fraction significantly increased compared with its baseline value and with that of the placebo group. The peripheral vascular resistance did not change after the administration of troglitazone, whereas plasma catecholamines significantly decreased, and CVRR remained unchanged in both groups. These hemodynamic changes suggest that a single oral dose of troglitazone induced inotropy without activation of the sympathetic nervous system.
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PMID:Troglitazone improves cardiac function in patients with congestive heart failure. 1237 99

Cardiovascular disease (CVD) is the most critical global health threat, which contributes more than one third of global morbidity. CVD includes heart disease, vascular disease, atherosclerosis, stroke and hypertension. The most important independent risk factors for CVD include dyslipidemia along with hypertension, obesity, sedentary lifestyle, diabetes and chronic inflammation. These factors are directly regulated by diet, metabolism and physical activity. Diets rich in fat and carbohydrate coupled to sedentary lifestyles have contributed to the increase in dyslipidemia, type 2 diabetes, obesity and CVD in the world. Discovery of Peroxisome Proliferator Activated Receptors (PPARs) as a key regulator of metabolic pathways has led to significant insight into the mechanisms regulating these processes. Three PPAR subtypes, encoded by distinct genes, are designated as PPAR-alpha, PPAR-delta (also know as beta) and PPAR-gamma. PPARs act as nutritional sensors that regulate a variety of homeostatic functions including metabolism, inflammation and development. PPAR-alpha is the main metabolic regulator for catabolism whereas PPAR-gamma regulates anabolism or storage. PPARs are expressed in the cardiovascular system such as endothelial cells, vascular smooth muscle cells and monocytes/macrophages. It has been shown that they play an important role in the modulation of inflammatory, fibrotic and hypertrophic responses. In 1997, a Glaxo patent described that Troglitazone (first PPAR-gamma ligand to reach market) reduced TNF-induced VCAM1 expression in HUVECs indicating the potential benefit in atherosclerosis. A series of patents from Eli Lilly and Dr. Reddy's Laboratories Ltd. between 1999 and 2005 described a variety of PPAR-alpha and -alpha,gamma dual ligands in a number of patents having glucose, triglyceride, cholesterol lowering, HDL elevating and body weight reducing activity. Patents from Metabolex and Tularik in 2001 and 2002 described the beneficial effects of SPPARM molecules for insulin resistance and diabetes, without showing concern on PPAR-gamma related side effects such as edema and body weight. GSK and Takeda described the potential effects of PPAR-delta modulators during 2001 to 2004 in few patents. Several clinical and preclinical studies have demonstrated the beneficial effects of PPAR ligands on various cardiovascular risk factors. This review intends to capture some of the key studies in this area as is described in some recent patents and literature.
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PMID:Role of PPAR in cardiovascular diseases. 1822 Oct 86

Thiazolidinediones (TZDs) are widely used in the type 2 diabetes mellitus (DMT2) treatment but have also been tested in cardiovascular prevention. DMT2 is associated with a marked increment in cardiovascular risk, and its prevention represents a main target in cardiometabolic protection. Both Troglitazone (Troglitazone in Prevention of Diabetes study) and Rosiglitazone (Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medication study) significantly reduced new-onset diabetes. A similar topic will be investigated with pioglitazone (Actos Now for Prevention of Diabetes). In the Prospective Pioglitazone Clinical Trial in Macrovascular events the primary end point (all-cause mortality, nonfatal myocardial infarction, stroke, acute coronary syndromes, endovascular or surgical intervention in the coronary/leg arteries and amputation above ankles) was unaffected, whereas the secondary one (all-cause mortality, nonfatal myocardial infarction and stroke) was reduced by pioglitazone (-16%, p=0.027) compared to placebo in 5,238 patients with DMT2 and macrovascular disease. In contrast, a meta-analysis (Nissen and Wolski, N Engl J Med. 2007;356:2457-2471) reported that rosiglitazone treatment is associated with a significant increase in myocardial infarction risk (p=0.03) and a borderline significant increase in the risk of death from cardiovascular causes (p=0.06). Nevertheless, the possibility that rosiglitazone might affect cardiovascular events should be evaluated by the ongoing trial Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycemia in Diabetes (RECORD). Interim findings early from RECORD did not show significant differences between the rosiglitazone and the control group regarding myocardial infarction and death from cardiovascular and any cause. Additional large-scale trials are awaited to clarify the of role TZDs in cardiovascular outcomes.
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PMID:Cardiovascular risk and cardiometabolic protection: role of glitazones. 1903 66