Correlation between thyroid hormone sensitivity and the risk of polycystic ovary syndrome.

OBJECTIVE: There has been some confusion in earlier research on the connection between thyroid function and polycystic ovary syndrome (PCOS). This research is aimed to probe into the correlation between thyroid condition and the risk of PCOS from a new standpoint of thyroid hormone sensitivity. METHODS: This research comprised 415 females with PCOS from Drum Tower Hospital Affiliated with the Medical School of Nanjing University, and 137 non-PCOS individuals were selected as the normal control. Based on free thyroxine (FT4), free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH), we calculated the thyroid hormone sensitivity indices, which consist of Thyroid Feedback Quantile-based Index (TFQI), Thyroid-stimulating Hormone Index (TSHI), Thyrotroph Thyroxine Resistance Index (TT4RI) and Free Triiodothyronine /Free thyroxine (FT3/FT4). The binary logistic regression model was adopted to investigate the correlation between thyroid hormone sensitivity indices with the risk of PCOS. Pearson or Spearman correlation analysis was employed to explore the association among thyroid-related measures with metabolic parameters in PCOS. RESULTS: Results of this research showed that females with PCOS had rising TFQI, TSHI, TT4RI, and FT3/FT4 levels compared with the control group. After adjustment for the impact of various covariates, there was no significant correlation between FT3/FT4 and the risk of PCOS; However, the odds ratio of the third and fourth vs. the first quartile of TFQI were 3.57(95% confidence interval [CI]:1.08,11.87) and 4.90(95% CI:1.38,17.38) respectively; The odds ratio of the fourth vs. the first quartile of TSHI was 5.35(95% CI:1.48,19.37); The odds ratio of the second vs. the first quartile of TT4RI was 0.27(95%CI 0.09,0.82). In addition, no significant correlation was observed between thyroid-related measures and metabolic measures in females with PCOS. CONCLUSIONS: A reduction in the sensitivity of central thyroid hormone is closely correlated with a higher risk of PCOS. Further research is necessary to corroborate our findings and the supporting mechanisms.

Effect of liver dysfunction on outcome of radioactive iodine therapy for Graves' disease.

Liver dysfunction is a common complication of Graves' disease (GD) that may be caused by excessive thyroid hormone (TH) or anti-thyroid drugs (ATDs). Radioactive iodine (RAI) therapy is one of the first-line treatments for GD, but it is unclear whether it is safe and effective in patients with liver dysfunction. 510 consecutive patients with GD receiving first RAI were enrolled in the study, and followed up at 3-, 6- and 12-month. Liver dysfunction was recorded in 222 (43.5%) patients. GD patients with liver dysfunction had higher serum levels of free triiodothyronine (FT3) (median 27.6 vs. 20.6 pmol/L, p < 0.001) and free thyroxine (FT4) (median 65.4 vs. 53.5 pmol/L, p < 0.001) levels than those with normal liver function. Binary logistic regression analysis showed that duration of disease (OR = 0.951, 95% CI: 0.992-0.980, p = 0.001) and male gender (OR = 1.106, 95% CI: 1.116-2.384; p = 0.011) were significant differential factors for liver dysfunction. Serum TSH levels were higher in patients with liver dysfunction at all 3 follow-up time points (p = 0.014, 0.008, and 0.025 respectively). FT3 level was lower in patients with liver dysfunction at 3-month follow-up (p = 0.047), but the difference disappeared at 6 and 12 months (p = 0.351 and 0.264 respectively). The rate of euthyroidism or hypothyroidism was higher in patients with liver dysfunction than in those with normal liver function at 3 months (74.5% vs 62.5%; p = 0.005) and 6 months (82.1% vs 69.1%; p = 0.002) after RAI treatment, but the difference did not persist at 12-month follow-up (89.6% vs 83.2%, p = 0.081).There were no statistically significant differences in treatment efficacy (94.48% vs 90.31%, p = 0.142), incidence of early-onset hypothyroidism (87.73% vs 83.67%, p = 0.277), and recurrence rate (4.91% vs 7.14%, p = 0.379) between the 2 groups at 12-month follow-up. In conclusion, the efficacy of RAI was comparable in GD patients with liver dysfunction and those with normal liver function.

Effect of probiotics combined with metformin on improvement of menstrual and metabolic patterns in women with polycystic ovary syndrome: a randomized clinical trial.

Objectives: The aim of this study was to access the efficacy of probiotics combined with metformin on improvement of menstrual and metabolic patterns in women with polycystic ovary syndrome (PCOS). Methods: In this single-centre, controlled, randomized clinical trial (NCT03336840), 60 non-obese women with PCOS were randomly assigned (1:1:1) to receive probiotics (4 g daily), metformin (1.5 g daily) or their combination for 12 weeks. The primary outcome was the improvement of menstrual patterns. The secondary outcomes included changes in anthropometric, metabolic profiles and hormonal levels. Results: After 12-week treatment, the recovery rate of menstrual cycle was 40% in probiotics group, 55% in metformin group and 80% in combination group (p = 0.035). Meanwhile, the ovulation rate was 30% in probiotics group, 55% in metformin group and 75% in combination group (p = 0.017). Serum anti-Müllerian hormone, testosterone, free androgen index, BMI, fasting blood glucose, HOMA-IR, lipid profiles were decreased after probiotics or metformin treatment in non-obese women with PCOS. Conclusion: In the present trial, probiotics combined with metformin was superior to probiotics or metformin alone to improve menstrual patterns in women with PCOS. Metabolic and hormonal profiles were also improved after probiotics or metformin treatment.

The correlation between vitamin D, glucose homeostasis and androgen level among polycystic ovary syndrome patients: a cross-sectional study.

MATERIAL AND METHODS: A total of 290 women with PCOS participated in this cross-sectional study. Glucose homeostasis was assessed by a 75-g oral glucose tolerance test and the concentration of serum 25-hydroxy vitamin D was determined among all subjects. The homeostasis model assessment of insulin resistance (HOMA-IR) was taken as the indicator of insulin resistance. Beta cell function was estimated using the insulinogenic index and the disposition index. Free androgen index (FAI) was used to represent the androgen level. RESULTS: In our study, 7.2% of the patients had Vit D severe deficiency, 75.2% had Vit D deficiency and 15.5% had vit D insufficiency. The level of serum 25(OH)D showed a significant positive association with insulinogenic index (r = 0.147, p < .05), disposition index (r = 0.280, p < .05), and SHBG (r = 0.178, p < .05) but exhibited a negative association with HOMA-IR (r = -0.198, p < .05), FAI (r = -0.178, p < .05). Adjusted age and BMI, 25(OH)D would be the dependent variable on disposition index [B = 0.259, 95%CI(0.041,0.477)] and FAI [B = -0.125, 95%CI(-0.232, -0.017)]. CONCLUSIONS: According to our results, the low levels of serum 25(OH)D were common in women with PCOS, which was speculated to be associated with glucose homeostasis and the androgen level.

A Multidisciplinary Approach for Tophi Wounds Caused by Glycogen Storage Disease Type 1a: A Rare Case.

ABSTRACT: Glycogen storage diseases (GSDs) are a group of rare inherited metabolic disorders caused by enzyme deficiencies in glycogen catabolism. The more common type, GSD type Ia, is caused by glucose-6-phosphatase deficiency and often complicated by gout from hyperuricemia. Here, the authors report a rare case of a tophi wound caused by GSD type Ia in a Chinese patient. Difficulties in this case included the control of abnormal blood markers, especially uric acid; removal of tophi deposited in the tissues; restoration of hand function after wound healing; and patient adherence to treatment and follow-up. A multidisciplinary team was set up consisting of experts from the authors' wound care center and the departments of endocrinology, orthopedics, and rehabilitation. The wound healed in 53 days and was followed up for about 7 months. During follow-up, the patient's hand function returned to normal, and no new tophi formed. Because GSDs are a congenital lifelong condition, regular follow-ups are especially important.

Suppression of p66Shc prevents hyperandrogenism-induced ovarian oxidative stress and fibrosis.

BACKGROUND: Rats with hyperandrogen-induced polycystic ovary syndrome (PCOS) have been shown to develop ovarian oxidative stress (OS) and fibrosis. The Sirt1 agonist, resveratrol, can reduce OS through inhibiting p66Shc in other models of OS. METHODS: We created a rat PCOS model with increased OS levels following treatment with one of the two androgens, dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT). The PCOS related features were determined by measurement of malondialdehyde (MDA) and superoxide dismutase (SOD) levels or by examining the reactive oxygen species (ROS) levels using the DCF-DA probe. The potential mechanisms by which p66Shc/Sirt1 mediates ovarian fibrosis were explored by western blotting, quantitative reverse transcription-PCR, immunofluorescence staining, and immunohistochemistry. RESULTS: Hyperandrogen dramatically augmented OS and activation of fibrotic factors in the ovary. Our data demonstrated that treatment with resveratrol enhanced Sirt1 and decreased ovarian OS as well as inhibited phosphorylation of p66Shc both in vivo and in vitro. The treatment suppressed fibrotic factor activation and improved ovarian morphology. Lentivirus- or siRNA-mediated p66Shc knockdown resulted in a dramatic enhancement of Sirt1 expression, down-regulation of ROS and suppression of fibrotic factors in granulosa cells. Moreover, p66Shc overexpression markedly increased the expression of fibrotic factors. Additionally, silencing Sirt1 induced a dramatic increase in p66Shc and enhanced activation of fibrotic factors. CONCLUSIONS: p66Shc may be a direct target of Sirt1 for inducing ROS and thus promoting fibrosis. Further exploration of the mechanisms of p66Shc in both fibrosis and OS may provide novel therapeutic strategies that will facilitate the improvement in PCOS symptoms and reproductive functions.

Association analysis between the tag single nucleotide polymorphisms of DENND1A and the risk of polycystic ovary syndrome in Chinese Han women.

BACKGROUND: The DENND1A gene is one of the most important sites associated with polycystic ovary syndrome (PCOS). We attempted to analyze the correlation between five single nucleotide polymorphisms (SNPs) in the DENND1A gene and the development of PCOS. METHODS: A total of 346 PCOS patients and 225 normal ovulatory women were involved in the case-control study. Clinical variables and hormones were recorded. According to the Hap Map database, five tagging SNPs (rs2479106, rs2768819, rs2670139, rs2536951 and rs2479102) in the DENND1A gene were identified. The TaqMan probe and the PCR-RFLP (restriction fragment length polymorphism) methods were used for revealing these genotypes. TaqMan Genotype Software was used to analyze the alleles of the five SNPs. RESULTS: Linkage disequilibrium and the gene frequency analysis demonstrated that the CCGGG haplotype might increase the risk of PCOS (P = 0.038, OR = 1.89, 95% CI = 1.027-3.481). Significant differences were found in genotypic and allelic distributions at the rs2536951 and rs2479102 loci between PCOS women and controls (P <  0.001). The LH levels and LH/FSH ratios were higher in PCOS patients than in the control group. A detailed analysis revealed that for the rs2479106 locus, these two values were significantly different in the control subjects who had AA, AG and GG genotypes (P = 0.013 and P = 0.007, respectively), and for the rs2468819 locus, these two values were significantly different among the PCOS patients with AA, AG and GG genotypes (P = 0.013 and 0.002, respectively). CONCLUSIONS: The tagging SNPs rs2479106 and rs2468819 in the DENND1A gene are associated with PCOS in the Chinese population, whereas rs2670139, rs2536951 and rs2479102 are not correlated with PCOS in the same population.

Influence of fetal sex on perinatal outcomes in women with gestational diabetes mellitus.

BACKGROUND: Fetal sex has recently been considered to be related to maternal glucose homeostasis and perinatal outcomes during pregnancy. Here, we investigated the effects of fetal sex on the perinatal outcomes of pregnancies with normal glucose tolerance (NGT) and gestational diabetes mellitus (GDM). METHODS: This was a retrospective cohort study of 1292 women with NGT and 1155 women with GDM. Pregnant women were divided into four groups according to the maternal glucose level and fetal sex. Logistic regression was used to evaluate the risks for adverse perinatal outcomes among NGT-males, NGT-females, GDM-males and GDM-females. RESULTS: NGT-males had higher risks for macrosomia and large for gestational age (LGA) than NGT-females with an odds ratio (OR) of 1.9 (95% CI 1.2-2.9). Additionally, GDM-males had higher risks for neonatal infection (OR, 3.0; 95% CI, 1.3-6.9), acute respiratory disorders (OR, 3.9; 95% CI, 1.1-13.7) and abnormal neonatal central nervous system development (OR, 3.1; 95% CI, 1.1-8.4) than GDM-females. Furthermore, there was a significantly higher risk for newborn infection (OR, 8.5; 95% CI, 1.1-66.8) in the GDM-male group than in the GDM-female group with a glycosylated hemoglobin A1c (HbA1c) level ≥5.5% in the late trimester of pregnancy, which was not observed with an HbA1c level of <5.5%. CONCLUSIONS: Male fetuses have worse perinatal outcomes than female fetuses, and the difference is more pronounced in GDM pregnancies. More postpartum care is needed for male fetuses, especially in GDM pregnancies with substandard glycemic control.

THE ASSOCIATION OF GESTATIONAL WEIGHT GAIN AND ADVERSE PREGNANCY OUTCOMES IN WOMEN WITH GESTATIONAL DIABETES MELLITUS.

Objective: To explore the association of excessive gestational weight gain (GWG) defined by the Institute of Medicine (IOM) targets and adverse perinatal outcomes in gestational diabetes mellitus (GDM) pregnancies, and whether a modified target might be related to a lower rate of adverse perinatal outcomes for GDM. Methods: This retrospective cohort study involved 1,138 women of normal glucose tolerance (NGT) and 1,200 women with GDM. Based on the IOM target, pregnancies were classified to appropriate GWG (aGWG), inadequate GWG, and excessive GWG (eGWG). Modified GWG targets included: upper limit of IOM target minus 1 kg (IOM-1) or 2 kg (IOM-2), both upper and lower targets minus 1 kg (IOM-1-1) or 2 kg (IOM-2-2). Results: The proportions of women achieving eGWG were 26.3% in NGT and 31.2% in GDM (P = .036); in comparison, for aGWG NGT, the risks of large for gestational age (LGA) were significantly higher in eGWG NGT (adjusted odds ratio [OR] 1.47; 95% confidence interval [CI] 1.02 to 2.13), aGWG GDM (adjusted OR 1.42; 95% CI 1.03 to 1.95), and eGWG GDM (adjusted OR 2.70; 95% CI 1.92 to 3.70). GDM pregnancies gaining aGWG based on the modified GWG targets (IOM-2, IOM-1-1, and IOM-2-2) had a lower prevalence of LGA and macrosomia delivery than that for similar pregnancies using the original IOM target (all P<.05). Conclusion: For aGWG GDM according to the IOM target, adhering to a more stringent weight control was associated with decreased adverse outcomes. A tighter IOM target might help to reduce the prevalence of adverse pregnancy outcomes. Abbreviations: aGWG = appropriate gestational weight gain; BG = blood glucose; BMI = body mass index; CI = confidence interval; eGWG = excessive gestational weight gain; GDM = gestational diabetes mellitus; GW = gestational weeks; GWG = gestational weight gain; HbA1c = hemoglobin A1c; iGWG = inadequate gestational weight gain; IOM = Institute of Medicine; LGA = large for gestational age; NGT = normal glucose tolerance; NICU = neonatal intensive care unit; OGTT = oral glucose tolerance test; OR = odds ratio; PARp = partial population attributable risks; SGA = small for gestational age.

Subclinical hypothyroidism is not a risk factor for polycystic ovary syndrome in obese women of reproductive age.

Obese women are at high risk for polycystic ovary syndrome (PCOS). Subclinical hypothyroidism (SCH) has been associated with weight gain, insulin resistance and impaired fertility, which are also factors involved in PCOS. However, there is limited information regarding the influence of SCH on the presence of PCOS. In order to determine whether SCH increases the prevalence of PCOS, we performed a cross-sectional study in a cohort of reproductive-aged obese women. All subjects underwent anthropometric evaluation, laboratory tests and ultrasound examination. Diagnosis of PCOS was based on the Rotterdam criteria. A total of 534 obese women were included and 108 (20.2%) of them were diagnosed with SCH. Patients with SCH showed similar insulin resistance, comparable androgen levels, and higher triglycerides levels (1.7 vs. 1.5 mmol/L, p = .002) compared to those with normal thyroid status. The frequency of PCOS did not differ between the two groups (56.1% for normal thyroid function vs. 60.2% for subclinical hypothyroidism, p = .514). In logistic regression analysis, SCH was not an independent risk factor for PCOS after adjusting for confounding factors (OR = 0.984, 95% CI 0.581-1.667). For the first time, our results suggest that SCH does not increase the risk of PCOS in obese women of reproductive age.

Expression and Histopathological Significance of Disabled-2 in Aldosterone-Producing Adenoma.

The current pathological diagnosis of aldosterone-producing adenoma (APA) is challenging because no histological markers of aldosterone production are available in routine practice. A previous study demonstrated that Disabled-2 (DAB2) is a specific marker of the zona glomerulosa (ZG) in rodents. The aim of the present study was to investigate the significance of immunohistochemical staining to detect DAB2 in the adrenal tissue of patients with APA. We investigated the expression of DAB2 in 36 adrenal glands with APA, 23 adrenal glands with cortisol-producing adenoma (CPA), and 33 adrenal glands with non-functioning adenoma (NFA). Immunohistochemical staining was performed using anti-DAB2 antibodies on paraffin-embedded sections. We analysed the expression of DAB2 semi-quantitatively by scoring staining intensity, and assessed the correlation of this information with the clinical findings. DAB2 mRNA expression in adenoma tissues was evaluated by RT-PCR. DAB2 was highly expressed in the ZG in normal human adrenal glands. DAB2 expression was heterogeneous in APA, with spotted, strong staining noted in most samples (25 of 36 APA). CPA and NFA also exhibited extensive low or moderate DAB2 expression. DAB2 mRNA was significantly increased and positively correlated with CYP11B2 in APA (p<0.05). In APA, the DAB2 score adjusted for tumour volume was positively correlated with plasma aldosterone (p<0.05). Patients with low or moderate DAB2 staining more frequently exhibited high blood pressure and were diagnosed at a younger age compared with patients with high DAB2 staining. The present study clearly demonstrates that DAB2 is a specific marker of the ZG in normal human adrenal glands but that DAB2 immunostaining is not sufficiently powerful for histopathological diagnosis of APA. DAB2 might be involved in excessive aldosterone biosynthesis and correlate with specific clinical characteristics of APA patients.

Comparative efficacy of anti-diabetic agents on nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized and non-randomized studies.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has a high prevalence in patients with type 2 diabetes mellitus (T2DM). In this study, we sought to provide a comprehensive assessment regarding the effects of anti-diabetic agents on NAFLD in patients with T2DM. METHODS: MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) with different anti-diabetic agents in T2DM. Observational trials were also recruited to expand our population. Hepatic fat content and liver histology were evaluated as primary outcomes. Pooled estimates were calculated using a fixed effect model. RESULTS: One thousand one hundred ninety-six participants in 19 RCTs and 14 non-randomized studies were included. Evidence from RCTs and observational studies suggested that greater hepatic fat content reduction and improved liver histology were seen in thiazolidinediones for 12-72 weeks; glucagon-like peptide-1 receptor agonists had beneficial effects on hepatic fat content after 26-50 weeks intervention, and insulin/metformin combination with 3-7 months improved hepatic fat content. Initiating metformin or dapagliflozin showed no benefit on hepatic fat content or liver histology in 16-48 weeks. Besides, nateglinide for 18 months was reported in a small sample-size RCT to improve hepatic fat content and liver histology. Sitagliptin therapy of 1 year also provided benefit on nonalcoholic steatohepatitis score in an observational study. CONCLUSIONS: For T2DM with NAFLD, administrating thiazolidinediones and glucagon-like peptide-1 receptor agonists seems to provide more identified advances in attenuating hepatic fat content. Further RCTs are warranted to assess the efficacy of various hypoglycemic agents on clinical outcomes associated with NAFLD in T2DM. Copyright © 2015 John Wiley & Sons, Ltd.

Modulation of expression of 17-Hydroxylase/17,20 lyase (CYP17) and P450 aromatase (CYP19) by inhibition of MEK1 in a human ovarian granulosa-like tumor cell line.

The differential steroid production in the theca and granulosa cells in ovary are resulted from unique enzyme expression profiles. Among them, c-fos, a downstream target of mitogen and extracellular signal-regulated kinases (MEK/ERK) signaling, takes part in this compartment. In this study, we investigated the effect of c-fos on the steady-state levels of CYP17 and CYP19 in human ovarian granulosa-like tumor cell line (KGN) by inhibiting MEK/ERK pathway with PD98059. As a result, our finding demonstrated the distinct distribution patterns of CYP17 and CYP19 in KGN. Moreover, the MEK/ERK pathway functions to inhibit the production of CYP17, while enhance the production of CYP19 in granulosa cells, probably involving a c-fos-dependent mechanism. In conclusion, factors such as c-fos may play a crucial role in the down-regulation of CYP17 and up-regulation of CYP19 in granulosa cells, thereby suppressing androstenedione synthesis.

[Pathomechanisms of podocyte injury in diabetic nephropathy and interventional effects of Chinese herbal medicine].

Podocyte injury is closely related to proteinuria in the progress of diabetic nephropathy(DN). The pathological characters of podocyte injury mainly refer to the change of podocyte form and function, including foot process effacement, reduction of podocyte number and density, podocyte apoptosis, podocyte epithelial-mesenchymal transdifferentiation(EMT)and podocyte hypertrophy. These pathological damages are controlled by multiple signaling pathways in the kidney, such as mammalian target of rapamycin(mTOR)/autophagy pathway, transforming growth factor(TGF)-ß1 pathway and Notch pathway. For podocyte injuries induced by high glucose or in murine models of DN, some Chinese herbal medicine(CHM)extracts, such as multiglycoside of Tripterygium wilfordii(GTW), triptolide(TP), astragaloside IV(AS-IV), astragalus polysaccharide(APS)and Panax notoginseng saponins(PNS), have the protective effects in vivo or in vitro. The preliminary studies in China showed that GTW improves podocyte injury in the DN model rats probably through regulating the activity of mTORC1 signaling pathway in the kidney. Therefore, it is the developmental direction for the further study to clarify the interventional effects of CHM based on podocyte injury-related signaling pathway in DN.

Epigenetic pattern changes in prenatal female Sprague-Dawley rats following exposure to androgen.

Androgen excess is generally considered to be one of the major characteristics of polycystic ovary syndrome (PCOS). Evidence from both clinical research and animal studies has revealed that this syndrome may have fetal origins, with epigenetics being proposed as the underlying mechanism. Our PCOS rat model induced by prenatal administration of 3mg testosterone from Embryonic Day (E) 16 to E19 showed polycystic ovaries, irregular oestrous cycles and endocrine disorders in adulthood. The methylation status of 16, 8 and 4 cytosine-phosphate-guanine (CpG) sites in the promoter regions of the androgen receptor (Ar), cytochrome P450 family 11, subfamily A, polypeptide 1 (Cyp11a1) and cytochrome P450, family 17, subfamily A, polypeptide 1 (Cyp17a1) genes, respectively, were measured by pyrosequencing. We identified three hypomethylated sites (CpG +58, +65 and +150) in Ar and one hypomethylated site (CpG +1016) in Cyp11a1 in peripheral blood cells of prenatally androgenised (PNA) rats. In ovarian tissue, five CpG sites of Ar (CpG +87, +91, +93, +98, +150) and one single CpG site in Cyp11a1 (CpG +953) were significantly hypomethylated in PNA rats, but the modified methylation of these two genes may not be sufficient to significantly alter levels of gene expression. Furthermore, tissue-specific methylation analysis revealed that both Ar and Cyp11a1 exhibited significant hypomethylation in testis in contrast with ovary and blood. PNA may lead to methylation pattern changes and the development of PCOS, but further studies are required to reveal causal relationships.

[Regulative mechanisms of mammalian target of rapamycin signaling pathway in glomerular hypertrophy in diabetic nephropathy and interventional effects of Chinese herbal medicine].

Glomerular hypertrophy is the main pathological characteristic in the early stage of diabetic nephropathy (DN), and its regulatory mechanism is closely related to mammalian target of rapamycin (mTOR) signaling pathway activity. mTOR includes mTOR complex 1 (mTORC1) and mTOR complex 2(mTORC2), in which, the upstream pathway of mTORC1 is phosphatidylinositol-3-kinase (PI3K)/serine-threonine kinase(Akt)/adenosine monophosphate activated protein kinase(AMPK), and the representative signaling molecules in the downstream pathway of mTORC1 are 4E-binding proteins(4EBP) and phosphoprotein 70 S6Kinase(p70S6K). Some Chinese herbal extracts could improve cell proliferation via intervening the expressions of the key molecules in the upstream or downstream of PIK/Akt/mTOR signaling pathway in vivo. As for glomerular mesangial cells(MC) and podocyte, mTOR plays an important role in regulating glomerular inherent cells, including adjusting cell cycle, energy metabolism and matrix protein synthesis. Rapamycin, the inhibitor of mTOR, could suppress glomerular inherent cell hypertrophy, cell proliferation, glomerular basement membrane (GBM) thickening and mesangial matrix deposition in model rats with DN. Some Chinese herbal extracts could alleviate glomerular lesions by intervening mTOR signaling pathway activity in renal tissue of DN animal models or in renal inherent cells in vivo and in vitro.

Role for sterol regulatory element binding protein-1c activation in mediating skeletal muscle insulin resistance via repression of rat insulin receptor substrate-1 transcription.

AIMS/HYPOTHESIS: Sterol regulatory element binding protein-1c (SREBP-1c) is a master regulator of fatty acid synthase and controls lipogenesis. IRS-1 is the key insulin signalling mediator in skeletal muscle. In the present study, we investigated the role of SREBP-1c in the regulation of IRS-1 in skeletal muscle cells. METHODS: L6 muscle cells were treated with palmitic acid (PA) or metformin. Adenovirus vectors expressing Srebp-1c (also known as Srebf1) and small interfering RNA (siRNA) against Srebp-1c were transfected into the L6 cells. Protein-DNA interactions were assessed by luciferase reporter analysis, electrophoretic mobility shift assay and chromatin immunoprecipitation assay. RESULTS: We found that both gene and protein expression of SREBP-1c was increased in contrast to IRS-1 expression in PA-treated L6 cells. SREBP-1c overproduction decreased Irs-1 mRNA and IRS-1 protein expression in a dose-dependent manner, and suppressed the resultant insulin signalling, whereas SERBP-1c knockdown by Serbp-1c siRNA blocked the downregulation of IRS-1 induced by PA. Protein-DNA interaction studies demonstrated that SREBP-1c was able to bind to the rat Irs-1 promoter region, thereby repressing its gene transcription. Of particular importance, we found that metformin treatment downregulated Srebp-1c promoter activity, decreased the specific binding of SREBP-1c to Irs-1 promoter and upregulated Irs-1 promoter activity in PA-cultured L6 cells. CONCLUSIONS/INTERPRETATION: Our data indicate for the first time that SREBP-1c activation participates in skeletal muscle insulin resistance through a direct effect of suppressing Irs-1 transcription. These findings imply that SREBP-1c could serve as an attractive therapeutic target for insulin resistance.

[Clinical implication of urinary protein markers in diabetic nephropathy and interventional effects of Chinese herbal medicine].

In clinic, some urinary protein makers can dynamically and noninvasively reflect the degree of renal tubular injury in patients with diabetic nephropathy (DN). These urinary biomarkers of tubular damage are broadly divided into two categories. One is newfound, including kidney injury molecule-1 (Kim-1), neutrophil getatinase-associated lipocalin (NGAL), liver-type fatty acid-binding protein (L-FABP) and cystatin C (CysC); the other one is classical, including beta2 microglobulin (beta2-MG), retinal binding protein (RBP) and N-acetyl-beta-D-glucosaminidase (NAG). It is reported that, the increases in urinary protein markers are not only closely related to the damage of tubular epithelial cells in DN patients, but also can be ameliorated by the treatment with Chinese herbal compound preparations or Chinese herbal medicine. Recently, although urinary proteomics are used in the protein separation and identification, the traditional associated detection of urinary protein markers is more practical in clinic. At present, it is possible that the associated detection of urinary biomarkers of glomerular and tubular damages may be a feasible measure to reveal the clinical significance of urinary protein markers in DN patients and the interventional effects of Chinese herbal medicine.

Dehydroepiandrosterone induces ovarian and uterine hyperfibrosis in female rats.

STUDY QUESTION: Do dehydroepiandrosterone (DHEA)-treated rats with polycystic ovary syndrome (PCOS) demonstrate a high level of fibrosis in ovarian and uterine tissues? SUMMARY ANSWER: DHEA induces ovarian and uterine hyperfibrosis in rats, probably involving a transforming growth factor-ß (TGF-ß)-dependent mechanism. WHAT IS KNOWN ALREADY: Chronic inflammation is the typical cause of fibrosis and is involved in the pathophysiological process of PCOS. Patients with PCOS are reported to have a higher serum level of TGF-ß, a well-characterized key pro-fibrotic factor. Fibrillin-3, a protein capable of interacting with TGF-ß, has been reported to be partially responsible for the fetal origin of PCOS. STUDY DESIGN, SIZE, DURATION: Female Sprague-Dawley rats were treated with a vehicle control or DHEA for 35 days, with subsequent analyses of changes in morphology and gene expression in ovarian and uterine tissues. Rescue groups treated with metformin or simvastatin and their corresponding controls were also analyzed. A total of 80 rats were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: The PCOS model was induced by daily administration of DHEA s.c. to 3-week-old female rats, and the rescue groups were injected daily with either metformin or simvastatin in addition to DHEA. Serum steroid hormone levels were measured by enzyme-linked immunosorbent assay. Samples were stained with hematoxylin and eosin for histological morphology, and Sirius Red and immunohistochemistry for revealing collagens. The expression of fibrosis-related genes was analyzed both at mRNA (real-time RT-PCR) and protein (western blot) levels. MAIN RESULTS AND THE ROLE OF CHANCE: DHEA-induced rats with PCOS exhibited significantly higher levels of fibrosis (collagen IV) in both ovarian and uterine tissues. In ovarian tissue, the expression of connective tissue growth factor (CTGF) increased following DHEA treatment at both mRNA and protein levels (P < 0.05, P < 0.001 versus controls, respectively). Similar results versus controls were obtained at a protein level for TGF-ß (P < 0.01) and mRNA level for fibronectin (P < 0.05) and angiotensin-II (P < 0.05). Likewise, in uterine tissue, the protein levels of both CTGF and TGF-ß were higher than controls following DHEA treatment (P < 0.05). Treatment with either metformin or simvastatin attenuated the fibrosis progression induced by DHEA exposure, as evidenced by a reduction of TGF-ß, plus CTGF or not, in both ovarian and uterine tissues. LIMITATIONS, REASONS FOR CAUTION: The particular mechanism involved in the DHEA-induced fibrosis was not fully revealed. WIDER IMPLICATIONS OF THE FINDINGS: Ovarian and uterine hyperfibrosis may occur in patients with PCOS and result in anovulation or other PCOS-related phenotypes. Anti-fibrotic therapy, for example metformin treatment, may be beneficial for patients with PCOS. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Natural Science Foundation of China (81170541) and the Natural Basic Research Program of China (973 program 2010CB945103). The authors declare no conflicts of interest.

Haplotype analysis of single nucleotide polymorphisms in anti-Müllerian hormone gene in Chinese PCOS women.

PURPOSE: Anti-Müllerian hormone (AMH) inhibits FSH-stimulated follicle growth and aromatase activity. The three fold higher serum AMH in PCOS patients may account for the increased number of small follicles and androgen level. We attempted to determine whether polymorphisms in AMH gene were associated with PCOS in Chinese han population. METHODS: A case-control study involving 475 PCOS patients and 512 normoovulatory women was conducted. Rs10407022 and rs8112524 were two tagging SNPs selected according to the HapMap database. Taqman assay was used for rs8112524 genotyping, and PCR-RFLP method for rs10407022. RESULTS: No significant difference was found in genotypic or allelic distributions of both of the two SNPs, rs10407022 and rs8112524, between PCOS women and controls. LH level and progesterone level were significantly higher in rs8112524 AA genotype in PCOS group (P = 0.012, 0.014 respectively). TA haplotype might enhance susceptibility to PCOS (P = 0.013, OR = 4.996, 95 % CI = 2.001-5.251), and GA haplotype might be protective (P = 0.000, OR = 0.117, 95 % CI = 0.049-0.417). CONCLUSIONS: Although individual TagSNPs in AMH gene do not affect susceptibility to PCOS, haplotypes of the two SNPs were associated with PCOS risk, as TA haplotype might enhance susceptibility to PCOS and GA inversely.