Bone sialoprotein, osteocalcin and calciotropic hormones: relationship to aging

To detect a specific and sensitive marker of bone turnover, this study was conducted on 60 healthy volunteer men classified according to age into three groups: The first group included 20 men in their third decade [with age range of 21-30 years], the second group included 20 men in their fifth decade [with age range of 41-50] and an elderly group included 20 men [age above 60 years]. Blood samples were collected after an overnight fast and serum was separated and kept frozen at -20C until analyzed for bone sialoprotein [BSP], osteocalcin, intact parathyroid hormone [PTH] and calcitonin by radioimmunoassay techniques. Serum BSP may be used as a novel sensitive and specific biochemical marker of bone turnover that may be used alone or in conjunction with osteocalcin in the routine investigations of the elderly for early prediction and follow up of senile osteoporosis

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

Atrial natriuretic factor [ANF] in type II diabetics: relationship to hypertension and nephropathy

Sixty-three non-insulin dependent diabetic patients, 11 healthy normotensive volunteers and 10 non-diabetic hypertensive men were included in this work. For all members of the study, a morning urine sample was collected without a preservative, centrifuged, and the supernatant was test for macroalbuminuria by albustix and the creatinine was determined by alkaline picrate reaction. Microalbuminuria was also determined by a double antibody 125I radioimmunoassay. Fasting blood sample was also taken from each individual and the serum was separated and the atrial natriuretic factor [peptide] was assayed by a competitive radioimmunoassay. The results revealed a highly significant increase in ANF levels in the whole diabetic group as compared with non-diabetic one and this increase of ANF in diabetics has been explained by the volume expansion associated with hyperglycemia and that raised plasma ANF could contribute to the glomerular hyperfiltration characteristics of early diabetes

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