Reduced plasma adiponectin levels relative to oxidized low density lipoprotein and nitric oxide in coronary artery disease patients

INTRODUCTION: Adiponectin is a circulating hormone that is produced exclusively by adipocytes and has antiinflammatory and anti-atherogenic properties. The hypothesis that there are differences in adiponectin levels between stable and unstable coronary-artery disease patients remains controversial. Furthermore, the potential relationships between the plasma adiponectin level and the inflammatory and non-inflammatory markers (oxidized low density lipoprotein and nitric oxide) in patients with stable and unstable coronary-artery disease relative to normal subjects have not been assessed. OBJECTIVES: To assess whether plasma adiponectin levels differ among patients with stable and unstable coronary-artery disease and among control subjects, and to correlate plasma adiponectin level with inflammatory and clinical risk factors (such as oxidized-LDL and nitric oxide) in these patients. METHODS: This study included 50 control subjects, 50 stable angina patients and 50 unstable angina patients with angiographically documented coronary-artery disease. Plasma adiponectin and oxidized-LDL levels were determined using an enzyme immunoassay. Plasma nitric oxide, high sensitivity C-reactive protein and lipid profile levels were also measured. RESULTS: Plasma adiponectin levels were lower in the unstable angina patients (4.9 ± 1.30 µg/mL) than in the stable angina patients (6.34 ± 1.0 µg/mL) or in the controls (9.25 ± 1.8 µg/mL); these levels were also significantly lower in stable angina patients versus controls (p<0.001). Plasma adiponectin levels were negatively correlated with oxidized-LDL, high sensitivity C-reactive protein, lipid profile and other clinical risk factors but positively correlated with nitric oxide. CONCLUSION: Plasma adiponectin levels were found to be lower in both stable and unstable angina patients relative to control subjects, and the correlation between plasma adiponectin and cardiovascular markers is weakened in these patients.

The role of central mechanisms in the anti-inflammatory effect of amitriptyline on carrageenan-induced paw edema in rats

OBJECTIVE: The present study was designed to further investigate the effect of amitriptyline, a classical tricyclic antidepressant, on carrageenan-induced paw edema in rats. METHODS: First, amitriptyline was administered intraperitoneally (i.p.) at doses of 20, 40 and 80 mg kg-1, 30 min before subplantar injection of carrageenan. Second, amitriptyline was given intracerebroventriculary or intrathecally at doses of 25, 50 and 100 μg/rat, 30 min prior to carrageenan challenge. Third, the effect of adrenergic receptor antagonists such as propranolol (10 mg kg-1, i.p.), prazosin (4 mg kg-1, i.p.) and yohimbine (10 mg kg-1, i.p.) and an opioid receptor antagonist (naloxone, 4 mg kg-1, i.p.) on the anti-inflammatory effect of amitriptyline (40 mg kg-1, i.p.) was investigated. RESULTS: Our data confirm that intraperitoneally administered amitriptyline exhibits a marked anti-inflammatory effect on carrageenan-induced paw edema in rats 4 h postcarrageenan challenge (P < 0.001). Intracerebroventricular (i.c.v.) administration of amitriptyline also reduced the development of paw edema at 4 h postcarrageenan (P < 0.001), but intrathecal (i.t.) application of amitriptyline failed to alter the degree of paw swelling. Furthermore, the applied antagonists did not modify the anti-inflammatory effect of amitriptyline. CONCLUSION: These results support the view that amitriptyline has a considerable anti-inflammatory effect on carrageenan-induced paw edema in rats and suggest that at least a part of this property could be mediated through supraspinal sites. Moreover, it seems unlikely that the investigated adrenergic and opioid receptors have a significant role in this effect of amitriptyline.

Antihyperlipidemic effect of peucedanum pastinacifolium extract in streptozotocin-induced diabetic rats

INTRODUCTION: Dyslipidemia is one of the most common complications of diabetes mellitus, significantly contributing to cardiovascular morbidity and mortality in diabetic patients. Peucedanum pastinacifolium Boiss. & Hausskn. is commonly used as an antihyperlipidemic vegetable in Iranian folk medicine. MATERIAL AND METHODS: In this study, we examined a hydroalcoholic extract of the aerial parts of Peucedanum pastinacifolium to determine its lipid-lowering activity in normal and streptozotocin (STZ)-induced diabetic rats. Experimental diabetes mellitus was induced by a single intraperitoneal administration of streptozotocin. Normal and streptozotocin-induced diabetic rats were separated into four groups. The groups were fed with 0, 125, 250 or 500 mg/kg body weight of Peucedanum Pastinacifolium hydroalcoholic Extract (PPE) in aqueous solution for 30 days. RESULTS: The results show that there were significant (P < 0.05) increases in total serum cholesterol, triglyceride and low-density lipoprotein cholesterol (LDL-C) and a decrease in high-density lipoprotein cholesterol (HDL-C) in streptozotocin-induced diabetic rats. Treatment of diabetic rats with PPE over a period of a month returned these levels close to control levels. CONCLUSION: These results suggest that PPE has hypolipidemic effects in streptozotocin-induced diabetic rats.