Effects of low carbohydrate diet and nutrition intervention on glucose and lipid metabolism and conception in obese polycystic ovary syndrome / 中国医师杂志

Objective To investigate the effects of low carbohydrate on body weight,glucose and lipid metabolism,sex hormones and conception of polycystic ovary syndrome (PCOS) with obese patients.Methods Sixty-four patients with PCOS and obesity and fertility were enrolled in this study from November 2015 to December 2016,and were randomly divided into low-carbohydrate diet group (study group) and control group.Before and after the intervention,the body weight,body fat composition analysis,reproductive endocrine hormone,glucose and lipid metabolism,menstrual cycle changes and conception were measured at 12 weeks after intervention.Results (1) After 12 weeks of treatment,the body weight,waist circumference,Body Mass Index(BMI)and visceral fat area of the study group were lower than those of the control group,the difference was statistically significant (P ＜ 0.05).(2) After 12 weeks of treatment,fasting blood glucose (FPG) of the two groups had no significant difference (P ＞ 0.05),while the 2 h postprandial blood glucose (PPG) of study group was significantly lower than the control group,the difference between the two groups was statistically significant (P ＜ 0.05).After treatment,the fasting insulin (FINS) of the study group and control groupwas respectively decreased by 48.8％ and 25.3％ compared with the baseline,the difference was statistically significant (P ＜ 0.05).(3) After treatment,the testosterone (T),free androgen index (FAI) and luteinizing hormone (LH) of the two groups decreased,compared to the control group,the study group decreased significantly (P ＜ 0.05).(4) The recovery rate of menstrual cycle and natural pregnancy rate in the study group were significantly better than those in the control group (P ＜ 0.05).Conclusions Low carbohydrate diet combined with metformin and moderate intensity exercise can effectively reduce weight,improve glucose,lipid metabolism and sex hormone levels,improve the natural pregnancy rate.

Metformin down-regulates the expression of regulators of G protein signaling in OLETF rats / 中国糖尿病杂志

Objective To investigate the expression of regulators of G protein signaling(RGS), including RGS2, RGS3 and RGS4 in OLETF rats, as well as the effects of metformin on these expressions. Methods LETO rats were used as control group. Eight-week-old male OLETF rats were assigned to two guoups randomly:model and trial(metfomin dose during 8~(th) to 22~(nd) weeks:300mg kg~(-1)·d~(-1);during 23rd to 28th weeks:400 mg·kg~(-1) ·d~(-1))groups. Expressions of RGS mRNA in aorta and heart werequantified by real-time PCR. Results RGS2, RGS3 and RGS4 mRNA of the thoracic aorta and left ventricle were significantly higher in model group than in control group (P<0.01). Compared with model group, metformin significantly reduced their mRNA in trial group (P<0.01). Conclusions Upregulation of RGS2, RGS3 and RGS4 mRNA expression in the thoracic aorta and left ventricle of OLETF rats is in correlation with cardiovascular lesions; while downregulation of their expression is in correlation with the action of metformin.

Disruption of the microfilament cytoskeleton induced by simulated microgravity affects NO/NOS system of osteoblasts / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of microfilament cytoskeleton changes induced by simulated microgravity on the NO/NOS system of osteoblasts, and explore the mechanism of weightlessness leading to osteoporosis.</p><p><b>METHODS</b>Mouse osteoblast-like cell line MC3T3-E1 were divided into simulated microgravity (by rotating clinostat) group, 0.5 microg/ml cytochalasins B group, simulated microgravity+cytochalasins B group, and normal gravity group. After cell culture for 48 h with corresponding treatments, immunofluorescence staining of the cells by FITC-phallacidin was performed to observe the changes of microfilament under laser confocal microscope. NOS activity of the cells was tested with NOS detection kit, and the NO concentration in the cell supernatant was measured with nitrate reductase method.</p><p><b>RESULTS</b>Depolymerization of the microfilament cytoskeleton with irregular arrangement and reduced tension fibers occurred in the cells except for those in the normal gravity group, which was especially obvious in the microgravity+cytochalasins B group. Compared with the normal gravity group, the cells in the other groups showed increased iNOS activity and NO concentration but decreased eNOS activity, especially obvious in simulated microgravity+ cytochalasins B group.</p><p><b>CONCLUSION</b>Disruption of the microfilament cytoskeleton induced by simulated microgravity can regulate the NO/NOS system to influence the signal transduction of the osteoblasts.</p>

Effects of certain vasoactive peptides on pathogenesis of vascular restenosis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the effects of several vasoactive peptides on the development of arterial restenosis after balloon angioplasty.</p><p><b>METHODS</b>In rat aortic artery restenosis model produced by denudation of aortic endothelia, we observed changes of endothelin (ET), angiotensin II (AII), calcitonin gene-related peptide (CGRP) and adrenomedullin (Adm) in plasma and aorta with radioimmunoassay and expression of hypertension-related gene (HRG-1) with semi-quantitative RT-PCR, and studied the effects of these peptides on intimal hyperplasia, intima/media ratio and MAPK activities of aortic artery after angioplasty respectively. Furthermore, in cultured cells, we studied the effects of these peptides on vascular smooth muscle cell (VSMC) proliferation and expression of HRG-1 of VSMC from spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats with 3H-TdR incorporation and RT-PCR respectively.</p><p><b>RESULTS</b>After angioplasty, the levels of ET and AII in plasma and aorta significantly increased, accompanied with VSMC proliferation and neointima hyperplasia. On day 10 after angioplasty, the levels of ET in plasma and aorta increased by 69% and 124% respectively, compared with sham group (P < 0.01); and the level of aortic AII increased by 80% (P < 0.01). Antiserum against ET or inhibitors of angiotensin converting enzyme (ACE) could significantly inhibit the proliferation of VSMC and neointima formation. Compared with the sham group, on day 3 after angioplasty, the CGRP levels in plasma and aorta increased by 64% and 89% respectively (P < 0.01) and the Adm levels in plasma and tissue increased by 129% and 102% respectively (P < 0.01). On day 10, intravenous administration of CGRP significantly inhibited the proliferation of VSMC and neointima formation induced by balloon aortic injury (by 66% and 79% respectively, P < 0.01). In addition, ET and AII attenuated the expression of HRG-1 in aorta and stimulated mitogen-activated protein kinase (MAPK) activity, while CGRP and Adm potentiated the expression of HRG-1 and inhibited MAPK.</p><p><b>CONCLUSIONS</b>ET and AII can stimulate the proliferation of injured intima while CGRP and Adm have an anti-hyperplasia effect after angioplasty. These 4 peptides are involved in the regulation of VSMC proliferation and affect the development of vascular restenosis by regulating the expression of HRG-1 and MAPK activity.</p>

Changes of different regulators of G protein signaling in spontaneously hypertensive rat / 中国介入心脏病学杂志

Objective To study changes of different regulators of G protein signaling(RGS) including RGS2, RGS3 and RGS4 mRNA in aorta and heart of spontaneously hypertensive rats (SHR), as well as their correlation with physiological phenotype of cardiovascular system. Methods Haemodynamic indexes of the cardiovascular system were measured. Heart weight and left ventricular weight were determined to calculate the ratio of heart weight to body mass (HW/BM) as well as left ventricular mass index (LVMI) in both male SHR and Wistar rats. Real-time PCR after RT were performed to determine the level of RGS mRNA in aorta and heart. Results Systolic blood pressure (SBP) of SHR was significantly higher than that of the control (229?29 vs. 121?12 mm Hg, P