In order to investigate the relationship between serum testosterone level and expression of androgen receptors in ovary in relation to insulin resistance in polycystic ovary syndrome (PCOS). Serum testosterone levels ...In order to investigate the relationship between serum testosterone level and expression of androgen receptors in ovary in relation to insulin resistance in polycystic ovary syndrome (PCOS). Serum testosterone levels were determined by radioimmunoassay in 17 patients with PCOS and 20 cases as control group. The expression of androgen receptor in ovary was detected by immunohistochemistry method. The results showed that serum testosterone level \[(3.1±1.5) nmol/L\] and insulin resistance index (0.85±0.49) in patients with PCOS were significantly higher than in control group (P<0.05), and showed a positive relation (r=0.65, P<0.01). The expression levels of androgen receptor in ovary of patients with PCOS were significantly higher than that in control group(P<0.05). The optical density value was positively related with insulin resistance index (r=0.59, P<0.01). It was concluded that androgen and androgen receptor could accelerate insulin resistance and the interaction of them might aggravate the pathophysiological change in PCOS.展开更多
The effects of metformin treatment on soluble leptin receptor (sOB-R) levels in women with polycystic ovary syndrome (PCOS) were investigated.This prospective and open-label study was conducted by the Department of Ob...The effects of metformin treatment on soluble leptin receptor (sOB-R) levels in women with polycystic ovary syndrome (PCOS) were investigated.This prospective and open-label study was conducted by the Department of Obstetrics & Gynecology at Union Hospital,Tongji Medical College of Huazhong University of Science and Technology,China.Fifty-five women with PCOS and insulin resistance (IR) were treated with metformin for 6 months.According to body mass index (BMI),the patients were divided into two groups:lean PCOS group (BMI <23 kg/m^2,n=34) and overweight or obese PCOS group (BMI >23 kg/m^2,n=21).Before and after treatment,serum luteinizing hormone (LH),follicle stimulating hormone (FSH),testosterone (T),androstenedione (A),dehydroepiandrosterone sulfate (DHEAS),insulin and sOB-R levels were determined.Thirty-one BMI-matched ovulatory women served as controls.The results showed:(1) The Homeostatic Model Assessment of Insulin Resistance (HOMA-IR),androgen levels and hirsutism scores were higher,and sOB-R levels were lower in PCOS groups than in control group.A subgroup analysis of lean and overweight or obese PCOS patients revealed there was significant difference in sOB-R level between lean PCOS group and overweight or obese PCOS group.There were no significant differences in anthropometric parameters between lean PCOS patients and BMI-matched controls.However,sOB-R level was significantly lower in lean PCOS women than in controls.(2) There was no correlation between sOB-R level and BMI,waist and hip circumference,total testosterone,androstendione,DHEAS,LH or hirsutism scores in PCOS patients,but there was a significant negative correlation between sOB-R and HOMA-IR.(3) After treatment with metformin for 6 months,serum insulin levels decreased,and sOB-R levels increased significantly (P<0.01).It was suggested that considering low sOB-R levels supposedly compensate diminished leptin action,PCOS per se might cause leptin resistance.It is likely that reduction of hyperinsulinemia produced by metformin effectively improves the sOB-R levels in PCOS.展开更多
Objective To document the possible effect of tyrosine kinase autophosphorylation on erythrocyte insulin-receptor after 12 weeks of metformin administration from the women with polycystic ovary syndrome （PCOS）. Metho...Objective To document the possible effect of tyrosine kinase autophosphorylation on erythrocyte insulin-receptor after 12 weeks of metformin administration from the women with polycystic ovary syndrome （PCOS）. Methods Thirty non-obese （BMI〈25 kg/m2） healthy women with normal reproductive cycles were evaluated by conventional criteria as the control 30 non-obese women with PCOS were categorized as nob-PCOS group, 40 obese women with PCOS （BMI 25 kg/m2） were categorized as ob-PCOS group. Subjects with PCOS were given metformin 850 mg/d for 12 weeks. The autophosphorylation of insulin receptor p Yl158, pyl162/1163 and insulin receptor-fl subunit （IR-~） from the solubilised erythrocyte were detected by ELISA. Results 1） Only the autophosphorylation level of p Yl l 58 in nob-PCOS and ob-PCOS groups was lower （P〈O.05） than that in control group and it can be increased after insulin stimulation （P〈O.05）; no similar changes were found in pYl162/1163 （P〉O.05）, even insulin-stimulated insulin receptor （P〉O.05） from both of PCOS groups. 2） After metformin administration, the p Y1158, p Y1162/p Y1163 autophosphorylation levels were increased （P〈O.O1） and further increased after plus insulin stimulation in vitro （P〈0. 01）. The p Y1162/1163 autophosphorylation level was increased in nob-PCOS group （P〈0.01） and ob-PCOS group （P〈0.05）. 3） No difference was found in concentration of IR-B between control group and both of PCOS groups following metformin administration （P〉0.05）. In summary, oral administration of metformin led to an significant increase in tyrosine kinase activity in both groups of PCOS. Conclusion The impairment of tyrosine autophosphorylation at pYl158 may contribute to insulin resistance, the tyrosine kinase activity per receptor of solubilised erythrocytes were significantly increased by metformin administration and the effect of metformin on insulin-receptor tyrosine kinase activity appeared to be independent of either of these variables.展开更多
基金This project was supported by a grant from the NationalNatural Sciences Foundation of China ( No.3 0 10 0 2 0 0 )
文摘In order to investigate the relationship between serum testosterone level and expression of androgen receptors in ovary in relation to insulin resistance in polycystic ovary syndrome (PCOS). Serum testosterone levels were determined by radioimmunoassay in 17 patients with PCOS and 20 cases as control group. The expression of androgen receptor in ovary was detected by immunohistochemistry method. The results showed that serum testosterone level \[(3.1±1.5) nmol/L\] and insulin resistance index (0.85±0.49) in patients with PCOS were significantly higher than in control group (P<0.05), and showed a positive relation (r=0.65, P<0.01). The expression levels of androgen receptor in ovary of patients with PCOS were significantly higher than that in control group(P<0.05). The optical density value was positively related with insulin resistance index (r=0.59, P<0.01). It was concluded that androgen and androgen receptor could accelerate insulin resistance and the interaction of them might aggravate the pathophysiological change in PCOS.
文摘The effects of metformin treatment on soluble leptin receptor (sOB-R) levels in women with polycystic ovary syndrome (PCOS) were investigated.This prospective and open-label study was conducted by the Department of Obstetrics & Gynecology at Union Hospital,Tongji Medical College of Huazhong University of Science and Technology,China.Fifty-five women with PCOS and insulin resistance (IR) were treated with metformin for 6 months.According to body mass index (BMI),the patients were divided into two groups:lean PCOS group (BMI <23 kg/m^2,n=34) and overweight or obese PCOS group (BMI >23 kg/m^2,n=21).Before and after treatment,serum luteinizing hormone (LH),follicle stimulating hormone (FSH),testosterone (T),androstenedione (A),dehydroepiandrosterone sulfate (DHEAS),insulin and sOB-R levels were determined.Thirty-one BMI-matched ovulatory women served as controls.The results showed:(1) The Homeostatic Model Assessment of Insulin Resistance (HOMA-IR),androgen levels and hirsutism scores were higher,and sOB-R levels were lower in PCOS groups than in control group.A subgroup analysis of lean and overweight or obese PCOS patients revealed there was significant difference in sOB-R level between lean PCOS group and overweight or obese PCOS group.There were no significant differences in anthropometric parameters between lean PCOS patients and BMI-matched controls.However,sOB-R level was significantly lower in lean PCOS women than in controls.(2) There was no correlation between sOB-R level and BMI,waist and hip circumference,total testosterone,androstendione,DHEAS,LH or hirsutism scores in PCOS patients,but there was a significant negative correlation between sOB-R and HOMA-IR.(3) After treatment with metformin for 6 months,serum insulin levels decreased,and sOB-R levels increased significantly (P<0.01).It was suggested that considering low sOB-R levels supposedly compensate diminished leptin action,PCOS per se might cause leptin resistance.It is likely that reduction of hyperinsulinemia produced by metformin effectively improves the sOB-R levels in PCOS.
基金supported by the Projects in the National Science & Technology Pillar Program during the Eleventh Five-year Plan Period (Grant No. 2007BAI04B04)the National Natural Science Foundation of China(Grant No 30672223)
文摘Objective To document the possible effect of tyrosine kinase autophosphorylation on erythrocyte insulin-receptor after 12 weeks of metformin administration from the women with polycystic ovary syndrome （PCOS）. Methods Thirty non-obese （BMI〈25 kg/m2） healthy women with normal reproductive cycles were evaluated by conventional criteria as the control 30 non-obese women with PCOS were categorized as nob-PCOS group, 40 obese women with PCOS （BMI 25 kg/m2） were categorized as ob-PCOS group. Subjects with PCOS were given metformin 850 mg/d for 12 weeks. The autophosphorylation of insulin receptor p Yl158, pyl162/1163 and insulin receptor-fl subunit （IR-~） from the solubilised erythrocyte were detected by ELISA. Results 1） Only the autophosphorylation level of p Yl l 58 in nob-PCOS and ob-PCOS groups was lower （P〈O.05） than that in control group and it can be increased after insulin stimulation （P〈O.05）; no similar changes were found in pYl162/1163 （P〉O.05）, even insulin-stimulated insulin receptor （P〉O.05） from both of PCOS groups. 2） After metformin administration, the p Y1158, p Y1162/p Y1163 autophosphorylation levels were increased （P〈O.O1） and further increased after plus insulin stimulation in vitro （P〈0. 01）. The p Y1162/1163 autophosphorylation level was increased in nob-PCOS group （P〈0.01） and ob-PCOS group （P〈0.05）. 3） No difference was found in concentration of IR-B between control group and both of PCOS groups following metformin administration （P〉0.05）. In summary, oral administration of metformin led to an significant increase in tyrosine kinase activity in both groups of PCOS. Conclusion The impairment of tyrosine autophosphorylation at pYl158 may contribute to insulin resistance, the tyrosine kinase activity per receptor of solubilised erythrocytes were significantly increased by metformin administration and the effect of metformin on insulin-receptor tyrosine kinase activity appeared to be independent of either of these variables.
