Serum leptin is correlated to high turnover in osteoporosis.

OBJECTIVE: Clinical data have suggested that obesity protects against osteoporosis. Leptin, mainly secreted by white adipose tissue, might be involved by mediating an effect on bone metabolism. This study was conducted to investigate a possible relationship of leptin and bone turn-over in postmenopausal women with osteoporosis. METHODS: We measured bone mineral density (BMD), serum leptin levels and markers of bone metabolism, including osteocalcin and cross-laps in 44 patients with osteoporosis. The main group consisted of 32 postmenopausal women. RESULTS: Mean serum leptin was 13.1 microg/L and showed no statistically significant difference to the levels measured in a collective of normal persons adjusted for age and BMI. When related to serum cross-laps as markers of bone resorption, a positive correlation (p<0.05) was observed, whereas no correlation with osteocalcin could be seen. CONCLUSIONS: A dual control of bone formation by leptin is assumed: This involves local mechanisms acting on osteoblasts and a central inhibitory effect on bone metabolism via a hypothalamic relay. Our data indicate that the net effect of circulating leptin may cause bone loss and is significantly related to high-turnover serum bone markers, at least in postmenopausal women with osteoporosis.

Effects of peripheral blood stem cell mobilization with granulocyte-colony stimulating factor and their transcoronary transplantation after primary stent implantation for acute myocardial infarction.

BACKGROUND: There is increasing evidence that transplantation of autologous stem cells improves cardiac function after acute myocardial infarction (AMI). For propagation of peripheral blood stem cells (PBSCs), application of granulocyte-colony stimulating factor (G-CSF) has been shown to be feasible, effective, and safe. We sought to evaluate a clinical and angiographic long-term safety profile of G-CSF application combined with transcoronary PBSC transplantation after recent stent implantation for AMI. METHODS: In patients with AMI and successful primary stenting of the infarct-related coronary artery, pharmacological bone marrow stimulation with G-CSF was initiated on the second postinterventional day. At least after 4 days of G-CSF therapy, apheresis as well as transcoronary transplantation of PBSCs was performed. The PBSCs were infused via a balloon catheter which was inflated inside the stent. Ventriculography and quantitative coronary angiography were performed at baseline and after 6 months. RESULTS: In the 20 patients who received PBSCs, mean left ventricular ejection fraction improved from 46.4% +/- 8.1% at baseline to 54.3% +/- 11% after 6 months (P < .001) because of an increase in systolic function in the infarct region. Control coronary angiography revealed a significant in-stent restenosis of the infarct-related coronary artery, defined as >50% stenosis, in 8 patients (40%), which was complicated by reinfarction in 2 patients (10%). CONCLUSIONS: Transcoronary transplantation of G-CSF-mobilized PBSCs favorably influences cardiac function and can be performed without adverse periprocedural events. However, significant in-stent restenosis and reinfarction seem to occur frequently during the following 6 months.

Plasma levels of alpha-melanotropin and ACTH-like immunoreactivities do not vary by season or skin type in women from southern and central Europe.

Melanotropins (MSH) are involved in tanning by stimulating melanocytes via the activation of the melanocortin-1 receptor to melanin production. Its main site of production is the pituitary gland, but alpha-MSH and related ACTH peptides are produced at other sites, including the skin. It has been hypothesized that systemic levels of alpha-MSH are controlled by a varying UV radiation (UVR) exposure. A seasonal rhythm of plasma levels has been proposed by some authors. We investigated healthy females in southern Spain and central Austria in summer and winter. The alpha-MSH and ACTH-like immunoreactivity plasma levels did not present marked differences between the groups of Malaga and Linz, dark and light skin and between seasons. An association of alpha-MSH to ACTH or cortisol levels could not be observed. Individual values of alpha-MSH were shown to be relatively constant at both times of measurement (p<0.05 by rank correlation) indicating an independent personal disposition for individual systemic alpha-MSH immunoreactivity levels. Our data do not support the concept of a marked involvement of melanotropins of pituitary origin in tanning, and no seasonal rhythm was observed.