Mala Herzberg

The effect of estrogen replacement therapy on zinc in serum and urine

Objective To ascertain the influence of estrogen replacement therapy (ERT) on blood and urinary zinc in postmenopausal women. Methods Thirty-seven postmenopausal women aged 53.2 ± 3.7 years were examined. All were treated with conjugated estrogens 0.625 mg and medroxyprogesterone acetate 5 mg. Zinc, magnesium, calcium, phosphate, and alkaline phosphatase levels in blood were measured before and after 6 and 12 months of treatment. Urinary excretion of zinc, magnesium, calcium, phosphate, and hydroxyproline were evaluated before and after 3, 6, and 12 months of therapy. Bone mineral density was examined before treatment and after 1.7 ± 0.3 years of ERT. Subjects were classified by 1) initial bone mineral density values (osteoporotics less than 0.850 g/cm2) and 2) zinc excretion as elevated (greater than 600 μg/g creatinine). Results At baseline, the values of most markers of bone turnover were higher in the osteoporotic women (Hotelling test, P = .06). After 1 year of treatment, a higher decrease of most indices was observed in the osteoporotic patients, and no statistical difference was found between the osteoporotic and the normal groups (Hotelling test, P = .31). A consistent negative association was observed between changes in bone mineral density and urinary zinc excretion in the osteoporosis group. Estrogen replacement therapy reduced excretion of zinc, magnesium, and hydroxyproline in the elevated zinc excretion group. Zinc excretion decreased 35% after 3 months and 26% after 1 year of treatment. The serum tests, with the exception of alkaline phosphatase, showed only negligible changes during ERT. Conclusion A significant decrease in zinc excretion was observed after 3 months of ERT. This change was more pronounced in women with osteoporosis and elevated zinc excretion. Because zinc excretion is almost uninfluenced by variation in diet, it may be used as an additional marker of changes in bone metabolism.

Carotenemia, skin colour and diabetes mellitus

SummaryCarotenemia with its yellowish-red tint is found in diabetes. The frequency of this phenomenon is unknown and the relationship between skin colour and blood carotenoid level is controversial. Frequently the suspicion of diabetes arising from inspection of the skin colour is in fact confirmed by the usual laboratory tests. We decided to examine skin colour, blood carotenoids, cholesterol and total blood lipid levels in 51 overt diabetics, 42 latent diabetics and 25 healthy subjects as well as 14 patients who had recently suffered an acute myocardial infarction. The healthy subjects showed blood carotenoid levels slightly higher than the patients. As is known, in cases of increased intake of carotenoid-rich fruit and vegetables the yellowish-red skin colour is marked. Diabetic patients however show this phenomenon even though they may not follow such a diet. This finding, although diagnostically useful, does not usually parallel a high carotenoid blood level. From this point of view overt and latent diabetes are similar.

Changes in plasma glucose, free fatty acids (FFA), cortisol, immunoreactive human growth hormone (IRHGH) and immunoreactive insulin (IRI) after tolbutamide-induced hypoglycemia in obese subjects

SummaryThe investigation was carried out on 30 subjects: 21 obese subjects and 9 normal weight controls. Twelve of the obese subjects and the 9 controls received 1 g tolbutamide i.v.; the other 9 obese subjects received 1.5 g tolbutamide, all in fasting condition. Plasma glucose, FFA, cortisol, serum IRI, and IRHGH were measured before and 15, 30, 60, 90 and 120 min after tolbutamide administration. A blunted response of cortisol and IRHGH to the hypoglycemic stimulus was observed in obese subjects receiving 1 g tolbutamide. The blunted response was reversed when 1.5 g tolbutamide was injected. Glucose levels were significantly higher at 60 min in the obese who received 1 g tolbutamide as compared to the controls, and were significantly lower 30, 60 and 90 min after the tolbutamide injection in obese who received 1.5 g tolbutamide. FFA showed significantly higher values 90 and 120 min after the injection in both groups of obese subjects: dose dependency was not observed. Insulin values were significantly higher 15 min after tolbutamide injection in the obese receiving 1.5 g tolbutamide when compared to those receiving 1 g and to the controls. The blunted plasma cortisol and serum IRHGH responses were reversed when larger doses were used. Some possible explanations for the results are discussed: a hypothalamo-pituitary underresponsiveness, a lower ratio of biologically active versus biologically unactive IRI, and peripheric insulin resistance in obesity.