Molecular mechanisms of aging: role of free radicals and melatonin

This study was conducted on 40 healthy volunteer men in order to find out the relationship between the pineal hormone melatonin, free radicals and age. They were classified according to their ages into two groups, group I comprised 20 men with an age ranging between 41-60 years and group II comprised 20 men with an age ranging between 61-78 years. Morning and evening blood samples were taken from each subject, then melatonin was administered orally in 3 mg single daily dose taken in the evening for six weeks, after which morning blood samples were taken. Serum was separated and analyzed for melatonin and free radicals levels. The results revealed that there was a highly significant decrease in serum melatonin levels in the older age group in comparison with the younger age, while free radicals showed an increase in the older age group compared with the younger age group

Microalbuminuria of incipient nephropathy in type 2 diabetics: Effect of pentoxifylline

Twenty six non insulin dependent diapetic [NIDD] patients and ten healthy controls are included in the present work. To all subjects included in the study, urine analysis for clinical proteinuria has been done. None of the diabetics have overt nephropathy [all with normal serum creatinine and no macroalbuminuria]. All patients have neither pyuria, nor evidence of cardiovascular disease. All patients are maintained on the same oral hypoglycaemic drug previously taken before the study. Fasting and two hours postprandial blood glucose, serum creatinine, urinary creatinine, microalbuminuria in ug albumin/mg urinary creatinine were determined to all subjects and contrals. Trental was adminstered in a dose of 800 mg for fifteen days to all diabetics and all the parameters are determined after the drug intake. The results revealed no significant change in microalbuminuria after pentoxifylline [Trental] therapy. However, individual data revealed that in twelve diabetics the microalbuminuria decreased and in fourteen diabetics the microalbuminuria increased after Trental. The increase in microalbuminuria has been explained on the basis of the mechanism of action of Trental on large vessels of the kidney while the decreasing effect of Trental on the microalbuminuria is probably due to its action on the red cell rheology with improvement of the microcirculation. The work clarifies that Trental has neither deleterious effect on the kidney function nor on the glucose tolerance. It is sugggested that Trental is useful on long term use in incipient diabetic nephropathy

Relationship between selenium and lipid hydroperoxide formation in human atherosclerosis

In this study, serum lipid hydroperoxides, selenium, HDL-cholesterol, total cholesterol as well as triglycerides [TC] were determined. The levels of total cholesterol and TG were increased in contrast to low HDL-cholesterol in atherosclerotics compared to the control group. The serum levels of lipid hydroperoxides were significantly in creased in atherosclerotics [126.68 + 13.9 ng/ml] compared to the control group [50.5+4.37 ng/ml]. Serum selenium shows no significant difference between atherosclertics [230 + 22 ng/ml] and the control group [200 +/- 11 ng/ml]. It is apparent that, although serum lipid hydroperoxides play a well established role in the pathogenesis of atherosclerosis, yet selenium alone-has no protective role against atherosclerosis. So, all antioxidants including selenium must be studied as a whole to verify their role in atherogenesis