Leptin induces a contracting effect on guinea pig tracheal smooth muscle via the Ob-R receptor mechanism: novel evidence.

The purpose of this study was to explore the potential contracting effect of leptin on isolated guinea pig tracheal smooth muscle (TSM), the possible mechanism, and the impact of epithelium denudation or allergen sensitization, respectively. An in vitro experiment investigated the effect of leptin at a concentration of 250-1000 nmol/L on isolated guinea pig TSM with an intact or denuded epithelium. Ovalbumin and IgE were used to test the impact of active and passive sensitization. The isolated TSM strips were incubated in Krebs solution and aerated with carbogen (95% O2 and 5% CO2) via an automated tissue organ bath system (n = 4 for each group). Isometric contractions were recorded digitally using iox2 data acquisition software. The possible mechanism of leptin-induced TSM contraction was examined by preincubation with leptin receptor (Ob-R) antagonist. Leptin had significant concentration-dependent contraction effects on guinea pig TSM (p < 0.05). Epithelium denuding and active or passive sensitization significantly increased the potency of the leptin. Preincubation with a leptin receptor (Ob-R) antagonist significantly reduced the contraction effects, suggesting an Ob-R-mediated mechanism. Leptin had a contracting effect on airway smooth muscles potentiated by either epithelium denuding or sensitization, and the Ob-R mechanism was a possible effect mediator.

Gestational Exposure to Synthetic Steroid Hormones Impaired Sperm Quantity and Quality in Wistar Rats.

This study was designed to investigate the effect of prenatal exposure to synthetic sex steroid on sperm quantity and quality, relative testicular and epididymal weights, and reproductive hormones level in adult Wistar rats. Forty male Wistar rats were divided into two groups: a test group (n = 20) that included mature rats that were born to dams exposed to gestational treatment with hydroxyprogesterone and a control group (n = 20) that included mature rats born to untreated dams. Compared to the control group, the test group showed a significant reduction in the sperm count, viability and motility, relative testicular and epididymal weights together with increased abnormal spermatozoa (p < 0.001). The reproductive hormonal assay revealed significantly lower serum testosterone and higher levels of FSH and LH among the test groups compared to the control (p < 0.05 for all). Prenatal exposure to synthetic progesterone negatively affected sperm production and function, relative testicular and epididymal weights, and reproductive hormone levels.

Serum Ghrelin Levels in Saudi Obese Asthmatic School-Children-Correlation with Interleukin-4, Interleukin-5, and Interleukin-21.

Ghrelin is a peptide hormone with direct or indirect effects on obesity and asthma. More data are required to understand the effect of ghrelin on the control and pathogenesis of these diseases. The aim of this study was to evaluate ghrelin levels in selected groups of children to identify the association between serum ghrelin, obesity, and the severity of asthma. The study included 401 school children selected from the Najran area and grouped into non-obese asthmatics, obese asthmatics, obese non-asthmatics and controls (non-obese non-asthmatics). Blood levels of ghrelin, interleukin (IL)-4, IL-5 and IL-21 were determined by ELISA. The mean ghrelin values were insignificantly increased in obese children compared with non-obese children. The highest blood ghrelin values were in the non-obese asthmatic group. Serum ghrelin, IL-4 and IL-21 levels were significantly increased in asthmatic children compared with non-asthmatic children (p < 0.05), and there were significant positive correlations between ghrelin and IL-4, IL-5, and IL-21 in asthmatic children. Furthermore, ghrelin, IL-4, and IL-21 levels were significantly higher in uncontrolled asthmatics compared with controlled-asthmatic children (p < 0.05). Asthma was the only significant risk factor for high ghrelin values. This study provides evidence supporting the anti-inflammatory role of ghrelin in the pathogenesis of asthma. Asthma might be considered as an important determinant of high ghrelin values in children.

Obesity and childhood asthma in male schoolchildren in Saudi Arabia: Is there a role for leptin, interleukin-4, interleukin-5, and interleukin-21?

BACKGROUND: Adiposity is associated with high serum levels of adipokines and chemokines which are possibly implicated in a co-existence of obesity and asthma. OBJECTIVES: Elucidate the possible roles of leptin, interleukin (IL)-4, IL-5 and IL-21 in linking obesity with childhood asthma. DESIGN: Cross-sectional, analytical. SETTING: Population of schoolchildren in a small Saudi city. SUBJECTS AND METHODS: The study included a representative sample of Saudi schoolchildren grouped as obese asthmatics, non-obese asthmatics, or obese nonasthmatics, with nonobese nonasthmatics as a control group. An asthma control test was done for the asthmatic groups. MAIN OUTCOME MEASURES: Serum levels of leptin, IL-4, IL-5, and IL-21. SAMPLE SIZE: 345 male schoolchildren with a mean (SD) age of 13.0 (2.3) years. RESULTS: Median serum leptin concentrations in obese asthmatics were significantly higher than in nonobese asthmatics ( P<.001). Uncontrolled asthmatics also had significantly higher leptin levels than controlled asthmatic children ( P<.002). Leptin levels were weakly but significantly correlated with the cytokines IL-4, IL-5, and IL-21. CONCLUSIONS: Leptin may contribute to a link between obesity and childhood asthma. Differences in IL-21 levels between nonobese and obese asthmatics suggest that the co-existence of asthma and obesity increased IL-21 levels. Leptin plus some proinflammatory cytokines especially IL-21 may be potential predictors for asthma control in children. LIMITATIONS: Blood sampling at different stages of asthma might influence cytokine expression. CONFLICT OF INTEREST: None.

Skin color. Could it be a new fingerprint?

OBJECTIVE: To prove that the difference in human skin color can be used as a new fingerprint. METHODS: A cross-sectional descriptive study was conducted in the Faculty of Medicine, The National Ribat University, Khartoum, Sudan between January and June 2010. The study consists of 139 subjects, which includes 41 Sudanese identical twins (82 subjects), 50 subjects from the general population, and 7 Chinese. All subjects were free of skin lesions. Based on reflectance spectrophotometry, the skin color has been read for all subjects from the inner upper arm using the Medisun skin check. Visual judgment on color differences was carried out directly with 3 normal observers, and through digital photos. RESULTS: Skin color was found to be different in all subjects under the study depending on visual judgment, digital photos, and skin color readings. Differences in skin color were also found between different parts of the body (color map). Color intensity reading in the first twin was 4.010 +/- 0.5, and in the second twin was 3.89 +/- 0.44 with a significant difference (p=0.001). The general population sample showed significant differences in skin color from each other, and from the Chinese group (p=0.002). CONCLUSION: In this study, we found that skin color between identical twins is different, as well as in the whole population, and could be a new personal identification method, which needs further international studies.