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Serum Osteocalcin Levels (serum + osteocalcin_level)
Selected AbstractsRelation of bone mineral density with clinical and laboratory parameters in pre-pubertal children with cystic fibrosisPEDIATRIC PULMONOLOGY, Issue 7 2009Nazan Cobanoglu MD Abstract To study bone mineral density (BMD) of pre-pubertal cystic fibrosis (CF) children, and its relation with clinical and laboratory parameters, we enrolled 16 CF (8 girls) (4,8 years), and 16 control children (8 girls) (4,8 years). After anthropometric measurements, BMD, serum calcium, phosphorus, total alkaline phosphatase (ALP), 25-hydroxy vitamin D (25-OHD), parathyroid hormone, osteocalcin, tumor necrosis factor (TNF)-,, soluble TNF-, receptor 2 (sTNFR2), and soluble IL-2 receptor (sIL-2R) levels, and urinary calcium and hydroxyproline excretions were assessed. Disease severity of CF patients was determined with Shwachman,Kulczycki clinical and Brasfield radiological scoring systems. The mean Shwachman,Kulczycki and Brasfield scores of CF patients were indicating well-controlled disease. The anthropometric measurements, mean BMD values, and serum calcium, phosphorus and parathyroid hormone levels were within normal range and similar in both groups. Serum osteocalcin levels were lower, and ALP and 25-OHD levels were higher in CF. Although 24-hr urinary calcium excretions was higher in CF patients, hydroxyproline excretions were similar in both groups. There was no difference between two groups for the serum levels of sIL-2R, TNF-, and sTNFR2. Children with low vertebral z -scores had higher serum sIL-2R levels in both groups, but the same relation could not be shown for TNF-, and sTNFR2. We may speculate that younger, healthier and well-nourished patients with CF may have normal BMD, but the bone disease develop as patients get older because of the other contributing factors. Future well-designed longitudinal studies with large cohorts might show a relation with BMD and cytokines in CF. Pediatr Pulmonol. 2009; 44:706,712. © 2009 Wiley-Liss, Inc. [source] Accentuated Ovariectomy-Induced Bone Loss and Altered Osteogenesis in Heterozygous N-Cadherin Null Mice,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2006Chung Fang Lai Abstract Ovariectomy-induced bone loss is accentuated in mice with germline Cdh2 haploinsufficiency, the result of a decreased osteoblastogenesis in the face of normal osteoclast number. Reduced N-cadherin abundance in these mice decreases cell,cell adhesion and alters signaling pathways important for osteoblast commitment and differentiation, thus providing in vivo evidence that N-cadherin,mediated cell,cell interactions are involved in homeostatic responses to increased bone remodeling. Introduction: We have shown that targeted expression of a dominant negative truncated form of N-cadherin (Cdh2) delays acquisition of peak bone mass in mice and retards osteoblast differentiation. We tested the role of this molecule in the skeletal homeostatic response to ovariectomy in mice with germline Cdh2 haploinsufficiency. Materials and Methods: Heterozygous Cdh2 null (Cdh2+/,) and wildtype mice were ovariectomized and followed up to 13 weeks by in vivo radiodensitometric and ex vivo histologic assessment of bone mass and turnover. Cells isolated from wildtype and Cdh2+/, mice were used to determine the alterations in bone cell function produced by partial loss of N-cadherin. Results: Bone mass was not significantly different between Cdh2+/, and wildtype littermates, but on ovariectomy, bone loss in Cdh2+/, mice was initially slower, but with time it became significantly greater than in wildtype mice. This accentuated bone loss was associated with lower osteoblast number and serum osteocalcin levels, with no differences in bone resorption. Although development of calcified nodules was faster in calvaria cells isolated from Cdh2+/, mice relative to Cdh2+/+ cells, bone marrow osteogenic precursors were lower in the former than in the latter genotypes. Cdh2 expression was downregulated with differentiation in wildtype calvaria cells, whereas cadherin-11 abundance remained unchanged. Furthermore, cell,cell adhesion (postconfluence) was decreased among heterozygous calvaria cells, as was cell proliferation (preconfluence), relative to wildtype cells. Finally, the abundance and cellular distribution of ,-catenin was minimally decreased in Cdh2+/, cells, whereas mitogen-activated protein kinase (MAPK) signaling was more active in Cdh2 insufficient cells. Conclusions:Cdh2 is involved in the homeostatic bone formation response to ovariectomy, presumably by regulating osteoprogenitors number and differentiation through stabilization of cell,cell adhesion and/or signaling modulation. [source] Circulating leptin levels and bone mineral density in children with biliary atresiaACTA PAEDIATRICA, Issue 2 2008Sittisak Honsawek Abstract Aim: To investigate circulating leptin levels in biliary atresia (BA) patients and the association of leptin with bone mineral density (BMD) and the severity of BA. Methods: We have examined 50 patients with BA and 15 matched healthy controls. Serum leptin, osteocalcin and C-terminal telopeptide of type I collagen (CTX) levels were measured by sandwich enzyme-linked immunosorbent assay (ELISA). BMD of the lumbar spine was measured by dual energy X-ray absorptiometry. Results: Serum leptin levels of BA patients were lower than those of healthy controls (2.7 ± 0.3 vs. 7.1 ± 1.7 ng/mL, p = 0.0001). Among the BA patients, serum leptin levels were significantly lower in patients with jaundice than patients without jaundice (1.7 ± 0.2 vs. 3.4 ± 0.4 ng/mL, p = 0.001). BMD of BA patients was correlated (p < 0.001) with leptin levels, age and BMI (r = 0.55, r = 0.75 and r = 0.58, respectively). The serum CTX levels were significantly higher in jaundice patients compared with jaundice-free patients and the healthy controls (0.6 ± 0.2 vs. 0.2 ± 0.1 ng/mL, p = 0.01), whereas the serum osteocalcin levels in BA patients were not different from those in the controls. Conclusion: Circulating leptin levels are correlated with BMD and the presence of jaundice in BA, suggesting that the leptin may play a physiological role in maintaining bone mass of BA patients with jaundice. [source] TOCOTRIENOL OFFERS BETTER PROTECTION THAN TOCOPHEROL FROM FREE RADICAL-INDUCED DAMAGE OF RAT BONECLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2005NS Ahmad SUMMARY 1.,Free radicals generated by ferric nitrilotriacetate (FeNTA) can activate osteoclastic activity and this is associated with elevation of the bone resorbing cytokines interleukin (IL)-1 and IL-6. In the present study, we investigated the effects of 2 mg/kg FeNTA (2 mg iron/kg) on the levels of serum IL-1 and IL-6 with or without supplementation with a palm oil tocotrienol mixture or ,-tocopherol acetate in Wistar rats. 2.,The FeNTA was found to elevate levels of IL-1 and IL-6. Only the palm oil tocotrienol mixture at doses of 60 and 100 mg/kg was able to prevent FeNTA-induced increases in IL-1 (P < 0.01). Both the palm oil tocotrienol mixture and ,-tocopherol acetate, at doses of 30, 60 and 100 mg/kg, were able to reduce FeNTA-induced increases in IL-6 (P < 0.05). Therefore, the palm oil tocotrienol mixture was better than pure ,-tocopherol acetate in protecting bone against FeNTA (free radical)-induced elevation of bone-resorbing cytokines. 3.,Supplementation with the palm oil tocotrienol mixture or ,-tocopherol acetate at 100 mg/kg restored the reduction in serum osteocalcin levels due to ageing, as seen in the saline (control) group (P < 0.05). All doses of the palm oil tocotrienol mixture decreased urine deoxypyridinoline cross-link (DPD) significantly compared with the control group, whereas a trend for decreased urine DPD was only seen for doses of 60 mg/kg onwards of ,-tocopherol acetate (P < 0.05). 4.,Bone histomorphometric analyses have shown that FeNTA injections significantly lowered mean osteoblast number (P < 0.001) and the bone formation rate (P < 0.001), but raised osteoclast number (P < 0.05) and the ratio of eroded surface/bone surface (P < 0.001) compared with the saline (control) group. Supplementation with 100 mg/kg palm oil tocotrienol mixture was able to prevent all these FeNTA-induced changes, but a similar dose of ,-tocopherol acetate was found to be effective only for mean osteoclast number. Injections of FeNTA were also shown to reduce trabecular bone volume (P < 0.001) and trabecular thickness (P < 0.05), whereas only supplementation with 100 mg/kg palm oil tocotrienol mixture was able to prevent these FeNTA-induced changes. [source] Altered bone metabolism in children infected with human immunodeficiency virusACTA PAEDIATRICA, Issue 1 2003G Zamboni Aim: Data on bone homoeostasis of children infected with human immunodeficiency virus (HIV), at the time of the gain in bone mass, are very rare. To determine possible alterations in bone metabolism, 13 prepubertal vertically HIV-infected children were studied. Methods: Viral load, CD4 count, interleukin-6 (IL-6), growth hormone, insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), acid-labile subunit (ALS), IGFBP-3 proteolysis, osteocalcin in blood and N-terminal telopeptide of type I collagen in urine were determined. Lumbar spine bone mineral density was examined by dual-energy X-ray absorptiometry. Results: Low osteocalcin levels were found in all patients. Low IGF-I was found in only six children, who had low CD4 count and high IL-6 levels, with normal levels of IGFBP-3 and ALS, absent IGFBP-3 proteolysis and decreased bone mineral density, irrespective of viral load or growth. Conclusion: Low serum osteocalcin levels appear to be an initial warning sign of possible altered bone metabolism in HIV-infected children. However, only when the immune system becomes more seriously compromised is bone loss measurable by bone densitometry. [source] | ||||||||||