Puberty has a key role in bone development. During puberty, several nutritional and hormonal factors play a major role in this process. The aim of this study was to determine the changes in areal bone mineral density (BMD), gonadal steroids, bone formation markers, and growth parameters in healthy Turkish pubertal girls and boys at different pubertal stages. In additional, we aimed to detect the relationship between BMD, sex steroids, and growth parameters, and to reveal the most important determinant of BMD in the pubertal period. BMD of the lumbar spine and total body was performed by dual-energy X-ray absorptiometry (Lunar DPX series) in 174 healthy pubertal children (91 girls, 83 boys), aged 11-15 years. Height and weight were measured. Pubertal stages were assesed. Bone formation markers and gonadal steroids were measured. BMD values significantly increased until stage IV in girls. In boys, BMD values also increased during puberty (P < 0.05), but it was significantly higher in stage IV compared with that in other pubertal stages (P < 0.01). Testosterone levels increased until stage IV in both sexes, particularly in boys. Estrogen levels significantly increased during puberty in girls, whereas it was significantly higher at stage IV in boys (P < 0.001). Bone-specific alkaline phosphatase (BAP) level was higher in early and midpuberty, and decreased in late puberty in girls (P < 0.001). BAP level was higher in stage IV in boys. Osteocalcin level was shown not to change significantly in pubertal stages. There was a modest correlation between BMD values and estrogen and testosterone levels in boys. In girls, there was a correlation between BMD values and estrogen levels only (P < 0.05). Weight was significantly associated with BMD in both sexes (P < 0.05). Estrogen had a significant influence on BMD in boys and girls. In conclusion, bone mass increased throughout puberty in both sexes. Peak bone mass was not achieved in girls, but was obtained at stage IV in boys. Bone formation markers were good predictors of bone mass in girls, but not in boys. Estrogen level made the greatest contribution to bone mineral acquisition in boys and girls. The achievement of peak bone mass was sustained by estrogen in boys. The major independent determinant of BMD in both sexes was weight.

BackgroundVitamin D is a lipid-soluble hormone found in certain foods and synthesized from precursors in the skin when exposed to ultraviolet light. Vitamin D plays a critical role in bone metabolism and many cellular and immunological processes and low levels have been associated with several chronic and infectious diseases. Vitamin D status is assessed by measuring the concentration of serum 25-hydroxyvitamin D [25(OH)D]. Vitamin D deficiency is reported to be common worldwide, but little has been reported about the vitamin D status of adults in Turkey. In this cross-sectional study, we determined the prevalence of 25(OH)D deficiency in adults residing in a city in the Aegean region of Turkey.MethodsA survey was conducted on a representative sample of adults over 20 years old in a non-coastal city at the end of the winter season. Of the 209 households selected by random sampling, 8.6% (n = 18) were unoccupied and 21.5% (n = 45) refused to participate. Blood samples were taken and questions about medical history, vitamin supplementation, sunlight exposure, and dietary calcium and vitamin D intake were asked in face-to-face interviews of 391 adults living in the remaining households.ResultsThe mean serum 25(OH)D concentration was 16.9±13.09 ng/mL, with 74.9% of the subjects having 25(OH)D deficiency (<20 ng/mL), 13.8% having insufficiency (20-29.99 ng/mL), and 11.3% of the subjects having sufficient 25(OH)D (≥30 ng/mL) levels. 25(OH)D deficiency was more common among females (78.7%) than males (66.4%, p < 0.05).ConclusionAdults living in an urban, non-coastal setting in Turkey have a high prevalence of vitamin D deficiency.

Structured exercise programme in asthmatic children resulted in better lung function, which may be attributed to its effect on antioxidant status.

PurposeThe aim of this study was to evaluate serum levels of leptin, ghrelin, and adiponectin in obese and non-obese children with asthma and in healthy non-asthmatic children, and analyze their relationships with clinical outcomes.MethodsThis study enrolled 40 obese and 51 non-obese children with asthma and 20 healthy children. Body mass index and serum leptin, ghrelin, and adiponectin levels were determined in all children. Asthma symptom scores and lung function test results were recorded for subjects with asthma.ResultsSerum leptin levels (11.8±7.9, 5.3±6.8, and 2.1±2.4 ng/mL in the obese asthmatic, non-obese asthmatic, and control groups, respectively) and adiponectin levels (12,586.2±3,724.1; 18,089.3±6,452.3; and 20,297.5±3,680.7 ng/mL, respectively) differed significantly among the groups (P<0.001 for all). Mean ghrelin levels were 196.1±96.8 and 311.9±352.8 pg/mL in the obese and non-obese asthmatic groups, respectively, and 348.8±146.4 pg/mL in the control group (P=0.001). The asthma symptom score was significantly higher in the obese children with asthma than in the non-obese children with asthma (P<0.001). Leptin and adiponectin levels were correlated with the asthma symptom score in non-obese children with asthma (r=0.34 and r=-0.62, respectively).ConclusionsObesity leads to more severe asthma symptoms in children. Moreover, leptin, adiponectin, and ghrelin may play important roles in the inflammatory pathogenesis of asthma and obesity co-morbidity.

BackgroundSchizophrenia is a debilitating mental disorder that presents impairments in neurocognition and social cognition. Several studies have suggested that the etiology of schizophrenia can be partly explained by oxidative stress. However, our knowledge about the implications of oxidative stress on illness-related cognitive deficits is still far from being clear. The aim of this work was to study the role of oxidative stress molecules on social cognition and neurocognition in patients with schizophrenia.MethodsWe assessed the peripheral levels of several molecules associated with oxidative stress, namely nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), homocysteine, superoxide dismutase (SOD) and neurotrophin 4/5 (NT4/5), in forty–one patients with schizophrenia and forty-three healthy participants. A battery of tests to measure neurocognition and social cognition was also administered to the schizophrenia group.ResultsWe found that the schizophrenia group presented substantially higher levels of oxidative stress than the control group, as revealed by elevated quantities of the pro-oxidants NO and MDA, and decreased levels of the antioxidants GSH, SOD and NT4/5. Interestingly, the levels of NT4/5, which have been shown to have antioxidant effects, correlated with executive functioning, as measured by two distinct tests (WCST and TMT). However, social cognition and symptom severity were not found to be associated with oxidative stress.ConclusionsWe propose a protective role of NT4/5 against oxidative stress, which appears to have a potentially beneficial impact on neurocognition in schizophrenia.

Abstract. The aim of this study was to determine serum vitamin B12, folic acid and homocysteine (Hcy) levels as well as MTHFR (C677, A1298C) gene polymorphisms in patients with vitiligo, and to compare the results with healthy controls. Forty patients with vitiligo and 40 age and sex matched healthy subjects were studied. Serum vitamin B12 and folate levels were determined by enzyme-linked immunosorbent assay. Plasma Hcy levels and MTHFR polymorphisms were determined by chemiluminescence and real time PCR methods, respectively. Mean serum vitamin B12 and Hcy levels were not significantly different while folic acid levels were significantly lower in the control group. There was no significant relationship between disease activity and vitamin B12, folic acid and homocystein levels. No significant difference in C677T gene polymorphism was detected. Heterozygote A1298C gene polymorphism in the patient group was statistically higher than the control group. There was no significant relationship between MTHFR gene polymorphisms and vitamin B12, folic acid and homocysteine levels. In conclusion, vitamin B12, folate and Hcy levels are not altered in vitiligo and MTHFR gene mutations (C677T and A1298C) do not seem to create susceptibility for vitiligo.

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Decreased NO levels mediated by increased oxidative stress significantly contribute to endothelial dysfunction observed in BD.