Abnormal expression of HSP70 may contribute to PCOS pathology

Abstract

Background The mechanism of the pathological change of polycystic ovary syndrome (PCOS) is still unclear. Previous studies have shown that PCOS is a chronic nonspecific low-grade inflammatory condition, and that heat shock protein (HSP)70 has a potent anti-inflammatory property. So the aim of this study is to investigate the correlation between HSP70 and the hormones and inflammatory factors and to find out the role of HSP70 in the pathogenesis of PCOS. Methods Twenty female Sprague–Dawley (SD) rats (aged 23 days and weighted 80-90 g) were randomly divided into two groups ( n = 10 per group), PCOS group and control group. PCOS group were subcutaneously injected with 6 mg/100 g dehydro-epiandrosterone (DHEA) for 20 consecutive days, the control group were subcutaneously injected with a solvent of equivalent amount. All the samples were collected in the morning fasting state, 12 h after the last administration. Histological examinations of ovarian tissues were analyzed. Hormone levels and inflammatory factors levels were measured by enzyme-linked immunosorbent assay (ELISA) kits. Results Serum concentrations of testosterone (T) and luteinizing hormone (LH) were significantly higher in the PCOS group than the control group ( P < 0.001), but the concentrations of estradiol (E 2 ), follicle stimulating hormone (FSH) and insulin didn’t show significant difference between these two groups. All the concentrations of inflammatory factors including C-reactive protein (CRP), interleukin (IL)-6, IL-18, and tumor necrosis factor (TNF)-α. were significantly higher in PCOS group than the control group ( P < 0.001). The expressions of HSP70 were significantly lower in serum but higher in ovarian tissues in the PCOS group than the control group. Spearman rank correlation analysis showed strong negative correlation of serum HSP70 levels with T, LH and all the detected inflammatory factors. Conclusion The abnormal expression of HSP70 correlated with testosterone and inflammatory factors, which indicates that HSP70 may play an important role in PCOS pathology.

The Abnormal Expression of HSP70 Is Related to Treg / Th17 Imbalance in PCOS Patients

“…In our study, Spearman rank correlation analysis showed that serum HSP70 levels were signi cantly negatively correlated with IL-10 and TGF-β levels, while signi cantly positively correlated with IL-6, IL-17, IL-23 and other in ammatory cytokines. Our previous study has shown that the levels of serum heat shock protein 70 in PCOS rats were decreased, and they were strongly negative correlated to testosterone, luteinizing hormone and in ammatory factors such as C-reactive protein, IL-6, IL-18, and tumor necrosis factor-α [27] This is contrary to our results in PCOS patients. The possible reason is that the transient superphysiological testosterone characteristics caused by the construction of PCOS rat model downregulated the expression of HSP70 in rat serum.…”

The Effect of Glutamine on Dehydroepiandrosterone-Induced Polycystic Ovary Syndrome Rats

“…In the present study, the hormones and ovarian morphology changes in the DHEA-induced PCOS and PCOS + glutamine rats were in accordance with the characteristic of PCOS patients as previous studies [2,9]. Significant decrease in the level of some amino acids including glutamine was observed in plasma in PCOS patients compared with the controls, these changes reflect the various metabolic pathways that participate in physiological functions [10].…”

“…The rats were randomly assigned into five groups (n = 10 /group), control group, PCOS group, PCOS + 0.5 g/kg Gln group, PCOS + 0.75 g/kg Gln group and PCOS + 1.0 g/kg Gln group. The PCOS rat model was established according to our previous study [9]. Briefly, all the PCOS rats were daily injected (subcutaneously) with 6 mg/100 g dehydroepiandrosterone (DHEA) (Aladdin Reagent Co., Ltd., Shanghai, China) which was dissolved in olive oil for 20 consecutive days, the control group was injected with an equivalent olive oil for 20 consecutive days.…”

Catechins from oolong tea improve uterine defects by inhibiting STAT3 signaling in polycystic ovary syndrome mice

“…High levels of phosphorylated NF-κB in uterine tissues suggested an increase in uterine inflammation. Chronic low-grade inflammation plays an important role in the pathogenesis of PCOS [ 45 ]. Patients with PCOS clearly have increased serum C-reactive protein (CRP) and pro-inflammatory cytokine levels, including TNF-α, IL-1β, and IL-6 [ 46 ].…”