|Keywords (Extracted from title, table of contents and abstract of thesis)
nitric oxide, lipid peroxidation, diabetes mellitus, hypertension, serum triglycerides, cholesterol, malondialdehyde, hydroperoxide
A total of 246 patients were included in this study, suffering from diabetes mellitus, or essential hypertension and those having hypertension in addition to diabetes mel1itus. 100 healthy persons were also included in the study, as control subjects. The purpose of study was to assess the levels of serum nitric oxide and lipid peroxidation, in these disease states and healthy controls. And also to compare the serum levels of nitrite, nitrate, malondialdehyde, and lipid hydroperoxides on the basis of gender in control healthy subjects. Further to evaluate the effect on the status of serum nitric oxide and lipid peroxidation before and after supplementation of vitamin E in volunteer healthy control subjects and hypertensive patients.
Serum triglycerides, total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, malondialdehyde and hydroperoxide levels were significantly increased in all the groups of patients whereas high-density lipoprotein cholesterol was' significantly decreased in contrast to control subjects. A non-significant increase was observed in levels of nitric oxide metabolites, i.e., nitrite and nitrate in diabetic patients as compared to non-diabetic control subjects. On the other hand diabetic patients with hypertension showed significantly high levels of nitrite and nitrate as compared to control subjects, however the levels of these parameters were not significantly different in diabetics with and without hypertension. Indices of lipid peroxidation i.e., malondialdehyde and hydroperoxides were found elevated in non-insulin dependent diabetics on comparison with insulin dependent diabetic patients and healthy subjects. No significant difference was noticed in serum concentrations of nitrite and nitrate, when insulin- or non-insulin dependent diabetic patients were compared with control subjects, or when both these types were compared with each other. Also on the basis of gender insignificant difference in serum nitrite and nitrate levels, between control male and female subjects, and a significant increase in the level of lipid peroxidation indices was observed in control healthy males as compared to control healthy female subjects.
Supplementation of vitamin E 600 mg daily for a period of 8 weeks was done in volunteer healthy controls and hypertensive patients. Results revealed no significant difference in serum lipids, lipoproteins and nitric oxide metabolites concentration, whereas a significant reduction in indices of lipid peroxidation were absented, before and at the end of supplementation period, in both volunteer healthy controls and hypertensive patients.
It is thus concluded that diabetes mellitus and essential hypertension are associated with greater than normal lipid peroxidation. This increase in oxidative stress may to some extent, contribute to endothelial dysfunction and reduced nitric oxide bioavailability in both the disease states. The effect of vitamin E supplementation in reduction of lipid peroxidation in both control subjects and hypertensive patients may provide as a useful measure in protecting against the deleterious effects of free radicals in health and disease.