Metabolic and carbohydrate characteristics of different phenotypes of polycystic ovary syndrome

Expression of Vascular Endothelial Growth Factor, Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 in Polycystic Ovarian Syndrome Rats and Its Implication

Polycystic ovary syndrome (PCOS) is a female endocrine disorder and frequently leads to infertility. Vascular endothelial growth factor (VEGF) has crucial roles and matrix metalloproteinase (MMPs) is correlated with cell migration. Both of them are involved in the occurrence and progression of PCOS. This study established a rat PCOS model using letrozole to measure the expression of VEGF, MMP-2 and MMP-9 (MMP-2/9), to analyze its correlation with PCOS. Letrozole was applied by gavage to establish rat PCOS model. General condition and ovarian tissue morphology were observed under a light field microscope. ELISA and immunohistochemistry (IHC) were used to detect serum or tissue expression of VEGF, MMP-2/9. Estrous cycle of rats was disrupted after 12 d for using letrozole. Vaginal smear showed abundant leukocytes with sparse keratinocytes. Ovary showed whitening and increased volume, with early phase small follicles plus lower granular cells or corpus luteum. Compared to control group, experimental group had significantly higher VEGF, MMP-2/9 (P < 0.05), which were higher in antral follicles than those in preantral follicle with higher expressions than primordial follicle (P < 0.05). In conclusion, VEGF, MMP-2/9 are abundantly expressed in both serum and tissues of PCOS rats.

Comparison of serum human Klotho levels and thiol/disulfide homeostasis in women with polycystic ovary syndrome and in healthy women

OBJECTIVES

Women with polycystic ovary syndrome (PCOS) have an increased cardiometabolic risk. Similarly, it was previously shown that atherosclerotic and cardiovascular risk is increased in the general population with lower serum Klotho levels. The aim of this study was to investigate the lotho and thiol/disulfide levels in women with non-obese PCOS compared to healthy controls and also to investigate the relationship of serum Klotho and thiol/disulfide homeostasis with cardiometabolic risk factors.

MATERIALS AND METHODS

In this prospective case control study, human serum alpha Klotho levels and thiol/disulfide homeostasis of women with PCOS aged between 19-33 were compared to their age and BMI matched non - PCOS healthy controls. In addition, the correlation of these molecules with other metabolic markers/measurements were also investigated.

RESULTS

Metabolic parameters such as mean waist circumference, lipid accumulation product, visceral adiposity index, fasting insulin, homeostasis model assessment of insulin resistance and triglyceride values were higher in the PCOS group (p = 0.038, p = 0.008, p = 0.001, p = 0.001, p = 0.002 and p = 0.002, respectively) compared to controls. However, mean serum Klotho and native thiol levels (respectively p < 0.0001 and p = 0.038) were lower compared to controls. Correlation analysis revealed that serum Klotho levels were negatively correlated with BMI, waist circumference, disulphide/total thiol, disulphide/native thiol, HOMA-IR and LAP-index.

CONCLUSIONS

Findings of decreased serum Klotho and native thiol values of the PCOS group compared to controls and the negative correlation of serum Klotho levels with metabolic markers supports the idea that decreased Klotho may be another mechanism by which cardiovascular risk is increased in women with PCOS.

TWEAK and monocyte to HDL ratio as a predictor of metabolic syndrome in patients with polycystic ovary syndrome

We aimed at analyzing serum TWEAK levels and monocyte/HDL ratio in polycystic ovary syndrome (PCOS) and their predictivity for metabolic syndrome (MS) in PCOS. We included 71 women with PCOS and 40 healthy controls without any cardiovascular risk factors in this cross-sectional study. Patient group was classified as MS positive (n = 34) and negative (n = 37). Study group had higher monocyte/HDL ratio and TWEAK levels (9.59 ± 2.82 vs 8.2 ± 2.46, p = .007 and 1085.54 ± 780.95 vs 694.88 ± 369.67 ng/ml, p = .009). Monocyte/HDL ratio and TWEAK levels were higher in MS positive group (10.47 ± 2.81 vs 8.77 ± 2.61, p = .01 and 1417.59 ± 921.52 vs 780.41 ± 455.67, p = .009). In multivariate regression analysis, monocyte/HDL ratio (>9.9, OR 3.42, 95%CI 1.41-5.78, p = .008) and TWEAK (>846.5 ng/ml, OR 5.49, 95%CI 3.14-7.59, p = .002) were found to be independent predictors of MS in study group. Discriminative value of monocyte/HDL ratio for MS in study group was evaluated by receiver operating curve. Area under curve for monocyte/HDL ratio was 0.669 with a sensitivity of 70.3% and specifity of 67.7%, cutoff value was >9.9. Receiver operating curve for TWEAK at >846.5 pg/ml threshold to diagnose MS in study group was performed and area under the curve was 0.769 with a sensitivity of 73% and specifity of 72%. TWEAK and monocyte/HDL ratio may be promising in predicting MS at early stages in PCOS to prevent future cardiovascular diseases by modifying life-style or giving pharmacotheraphy.

An update of genetic basis of PCOS pathogenesis

Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder that affects 5-20% of reproductive age women. PCOS clinical symptoms include hirsutism, menstrual dysfunction, infertility, obesity and metabolic syndrome. There is a wide heterogeneity in clinical manifestations and metabolic complications. The pathogenesis of PCOS is not fully elucidated, but four aspects seem to contribute to the syndrome to different degrees: increased ovarian and/or adrenal androgen secretion, partial folliculogenesis arrest, insulin resistance and neuroendocrine axis dysfunction. A definitive etiology remains to be elucidated, but PCOS has a strong heritable component indicated by familial clustering and twin studies. Genome Wide Association Studies (GWAS) have identified several new risk loci and candidate genes for PCOS. Despite these findings, the association studies have explained less than 10% of heritability. Therefore, we could speculate that different phenotypes and subphenotypes are caused by rare private genetic variants. Modern genetic studies, such as whole exome and genome sequencing, will help to clarify the contribution of these rare genetic variants on different PCOS phenotypes. Arch Endocrinol Metab. 2018;62(3):352-61.