These data indicate that GH replacement has a negative effect on leptin levels and may also produce a slight unfavorable effect on carbohydrate metabolism. In addition, the changes observed in the adipokine profile appear to be independent of body mass index.

In a double-blind, placebo-controlled, randomized crossover study, 15 stable mild hyperglycemic patients without treatment and with features of metabolic syndrome were treated with cerivastatin (0.4 mg/day) or placebo for 3 months. The insulin sensitivity index during the euglycemic-hyperinsulinemic clamp (EHC; 5.4 mmol/l; 80 mU ⅐ m ؊2 ⅐ min ؊1 ) was increased by cerivastatin treatment (66.39 ؎ 3.9 nmol ⅐ lean body , 0.91 ؎ 0.01; P < 0.01 and P < 0.05, respectively). During statin treatment, the first-phase insulin response increased from 2.07 ؎ 0.28 to 2.82 ؎ 0.38 pmol ⅐ l ؊1 ⅐ pmol ؊1 (P < 0.05). The second phase of insulin responses examined by C-peptide and insulin levels averaged during the hyperglycemic clamp (20 mmol/l) was unchanged. In conclusion, this study demonstrates that 0.4 mg cerivastatin therapy improves first-phase insulin secretion and increases insulin-mediated glucose uptake and respiratory quotient in the early state of obese type 2 diabetes. Diabetes 51:2596 -2603, 2002 T ype 2 diabetes represents the final stage of a progressive syndrome characterized by targettissue resistance to insulin that cannot be overcome by ␤-cell hypersecretion (1). In the initial period, some subjects accumulate a constellation of major risk factors such as central (intra-abdominal) obesity, hypertriglyceridemia, low HDL cholesterol, raised blood pressure, and insulin resistance associated with proinflammatory states (2). In this state, patients receive primary care from their physicians with a recommendation for lifestyle changes (3). However, most people do not adequately maintain weight loss after participating in weightcontrol programs (4), and some subjects develop late micro-and macrovascular complications of diabetes. Approaches to reduce coronary heart disease have been focused on statins therapy (5,6). Several pleiotropic effects of statins could represent a potential means for controlling multifactorial atherosclerosis observed in diabetes. A post hoc analysis in the West of Scotland Coronary Prevention Study database provided evidence for the protective treatment effect of Pravastatin on the development of diabetes (7). However, whether statin treatment is beneficial in glucose metabolism of diabetes still remains to be seen. Suppression with high doses of statins on VLDL production of patients with type 2 diabetic hypertriglyceridemia could effect the release of fatty acids (FAs) from the liver (8). It is now recognized that plasma FA concentrations have profound effects on insulin action and glucose metabolism (9,10). Finally, cholesterol is a key component in the regulation of signal transduction through membrane lipid-ordered microdomains and in the regulation of gene expression through cholesterol-activated transcription factors (11). Intracellular cholesterol might serve as a link between fat cell size, glucose metabolism, and adipocyte metabolic activity (12). Sterol regulatory element-binding protein is implicated as a major mediator of insulin action (13). The major aim of the present study w...

The effect of exposure to lead on the longitudinal development of bone and on bone mass was studied in rats. A group of 35, 50-day-old female Wistar rats was divided into a control group of 15 rats and an experimental group of 20 rats fed a diet supplemented with 17 mg of lead acetate per kg feed for 50 days. Total body bone densitometry (TBBMC) was performed the day before ending the 50-day experiment. On day 50, all rats were killed and their right femur and 5th lumbar vertebra were dissected. The bones were cleaned of soft tissue and femoral length and vertebral length were measured with a caliper and all bones were weighed on a precision scale. Final body weight (P < 0.05), TBBMC (P < 0.005), and femur weight (P < 0.005) were significantly lower in the control group. Femur length did not differ between groups, but the length of the 5th lumbar vertebra was greater in the control group (P < 0.05). Histomorphometry of the femur showed that Cn-BV/TV, Tb-N, Tb-Th were lower (P < 0.05 in all) and Tb-Sp was higher (P < 0.05) in the group given the lead-supplemented diet. These findings suggested lead-induced inhibition of axial bone development and a histomorphometric decrease in bone mass, produced mainly by enhanced resorption, and a densitometric increase in bone mass, produced by lead accumulation in bone.

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