Very low dose spironolactone protects experimentally-induced polycystic ovarian syndrome from insulin-resistant metabolic disturbances by suppressing elevated circulating testosterone

Sinapic acid modulates oxidative stress and metabolic disturbances to attenuate ovarian fibrosis in letrozole-induced polycystic ovary syndrome SD rats

Sinapic acid (SA) is renowned for its many pharmacological activities as a polyphenolic compound. The cause of polycystic ovary syndrome (PCOS), a commonly encountered array of metabolic and hormonal abnormalities in females, has yet to be determined. The present experiment was performed to evaluate the antifibrotic properties of SA in rats with letrozole-induced PCOS-related ovarian fibrosis. SA treatment successfully mitigated the changes induced by letrozole in body weight (BW) (p < .01) and relative ovary weight (p < .05). Histological observation revealed that SA reduced the number of atretic and cystic follicles (AFs) and (CFs) (p < .01), as well as ovarian fibrosis, in PCOS rats. Additionally, SA treatment impacted the serum levels of sex hormones in PCOS rats. Luteinizing hormone (LH) and testosterone (T) levels were decreased (p < .01, p < .05), and follicle-stimulating hormone (FSH) levels were increased (p < .05). SA administration also decreased triglyceride (TG) (p < .01) and total cholesterol (TC) levels (p < .05) and increased high-density lipoprotein cholesterol (HDL-C) levels (p < .01), thereby alleviating letrozole-induced metabolic dysfunction in PCOS rats. Furthermore, SA treatment targeted insulin resistance (IR) and increased the messenger RNA (mRNA) levels of antioxidant enzymes in the ovaries of PCOS rats. Finally, SA treatment enhanced the activity of peroxisome proliferator-activated receptor-γ (PPAR-γ), reduced the activation of transforming growth factor-β1 (TGF-β1)/Smads, and decreased collagen I, α-smooth muscle actin (α-SMA), and connective tissue growth factor (CTGF) levels in the ovaries of PCOS rats. These observations suggest that SA significantly ameliorates metabolic dysfunction and oxidative stress and ultimately reduces ovarian fibrosis in rats with letrozole-induced PCOS.

Low-dose spironolactone combats dyslipidemia and hepatic inflammation by modulating PCSK9 in rat model of polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder among women and it is associated with overt metabolic derangement. Circulating lipids are regulated by proprotein convertase subtilisin/kexin type 9 (PCSK9) which blocks low density lipoprotein (LDL) receptors especially in the liver. The liver is highly vulnerable in dyslipidemia as lipid accumulation leads to progression of non-alcoholic fatty liver disease (NAFLD). An array of scientific endeavours hold that low-dose spironolactone (LDS) is beneficial as intervention for PCOS traits, but this claim is yet to be fully elucidated. The aim of this study was to investigate the effect of LDS on dyslipidemia and hepatic inflammation in rats with letrozole (LET)-induced PCOS and to assess the possible involvement of PCSK9 in these effects. Eighteen female Wistar rats were randomly assigned into 3 groups. The control group received vehicle (distilled water; p.o.), LET-treated group received letrozole (1 mg/kg; p.o.), LET+LDS-treated group received LET plus LDS (0.25 mg/kg, p.o.) for 21 days. Exposure to LET increased body and hepatic weights, plasma and hepatic total cholesterol (TC), TC/HDL, LDL, interleukin-6, MDA, PCSK9, ovarian degenerated follicles and hepatic NLRP3 intensity, reduced GSH and normal ovarian follicles. Interestingly, LDS averted dyslipidemia, NLRP3-dependent hepatic inflammation and ovarian PCOS traits. It is evident herein that LDS ameliorates PCOS traits and combats dyslipidemia and hepatic inflammation in PCOS by a PCSK9-dependent mechanism.

Metformin combined with spironolactone vs. metformin alone in polycystic ovary syndrome: a meta-analysis

Aims

Due to its high heterogenicity and unclear etiology, there is currently no specific treatment for polycystic ovary syndrome (PCOS). Metformin, as an insulin sensitizer, combined with spironolactone, an antiandrogen medication, may exert complementary effects on PCOS. We therefore performed a meta-analysis of trials in which metformin combined with spironolactone was applied to treat PCOS to evaluate the efficacy and safety of the combination therapy.

Methods

We retrieved the PubMed, Embase, Scopus, Cochrane Library, CNKI, CBM, Wangfang, and VIP databases for literatures published from their inception to December 16, 2022 on the effects of metformin combined with spironolactone in the treatment of PCOS. Inclusion criteria according to P.I.C.O.S criteria were: PCOS patients, metformin combined with spironolactone interventions, metformin alone control group, and randomized controlled trials with the following outcome data: body mass index (BMI), hirsutism score, luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (TT), fasting blood glucose (FBG), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), and side effects including nausea, vomiting, diarrhea and drug withdrawal.

Results

Our results revealed that metformin combined with spironolactone significantly reduced BMI and TT, but that it exerted no significant effects on hirsutism score, or on FSH or LH concentrations. Combined treatment also resulted in a significant diminution in FBG and insulin resistance using the HOMA-IR when the interventional time was greater than 6 months. In addition, the combination did not have a higher occurrence of adverse reactions than metformin alone.

Conclusion

Compared with metformin alone, metformin combined with spironolactone therapy may be more effective in reducing BMI and serum androgen levels, but the combination showed no significant effect on the hirsutism score or gonadotropin hormone levels, and was not associated with an elevation in side-effects. Moreover, when the treatment course was greater than 6 months, combination therapy reduced FBG and improved insulin resistance more effectively than metformin alone. However, more research is needed to determine the most effective course of treatment.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022355515.

Low-dose spironolactone ameliorates adipose tissue inflammation and apoptosis in letrozole-induced PCOS rat model

BACKGROUND OF STUDY

Globally, many reproductive aged women are affected by polycystic ovarian syndrome (PCOS), which is a common endocrine and metabolic disorder that is linked with adipose dysfunction and chronic low-grade inflammation. Spironolactone (SPL), a mineralocorticoid receptor blocker has been documented as a metabolic modulator. However, its immunomodulatory effect in PCOS is unknown. Therefore, the present study hypothesized that SPL would ameliorate adipose dysfunction and inflammation in experimental PCOS animals.

MATERIALS AND METHODS

Female Wistar rats that were 8 weeks old were allocated into three groups. Group 1 received vehicle (distilled water; p.o.), group 2 received letrozole (1 mg/kg; p.o.) and group 3 received letrozole plus SPL (0.25 mg/kg, p.o.). The administration was performed once daily for 21 days.

RESULTS

The experimental PCOS animals showed insulin resistance, hyperinsulinemia and hyperandrogenism as well as oxidative stress and elevated inflammatory biomarkers (NF-kB/TNF-/IL-6) as well as a significant decrease in triglycerides, total cholesterol, free fatty acids, GSH and G6PD in the adipose tissue of PCOS animals. In addition, immunohistochemical assessment of adipose tissue showed significant expression of BAX and inflammasome, indicating apoptosis and inflammation compared to control animals. Nevertheless, administration of SPL attenuated these perturbations.

CONCLUSION

Altogether, the present study suggests that low-dose spironolactone confers protection against adipose dysfunction in experimental PCOS animals by attenuating inflammation, oxidative stress and cellular apoptosis.

Rhamnocitrin Attenuates Ovarian Fibrosis in Rats with Letrozole-Induced Experimental Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine-related cause of infertility in women and has an unknown etiology. Studies have shown that rhamnocitrin (Rha) exhibits positive effects on the reproductive system. This study investigated Rha's antifibrotic effects on PCOS rats and revealed its underlying mechanisms. Female SD rats were randomized into 4 groups (n = 8, each); the control group received tea oil by intraperitoneal injection and 1% w/v CMC by oral gavage; the PCOS group received letrozole (1 mg/kg); the PCOS+Rha group received letrozole and Rha (5 mg/kg); the PCOS+Met group received letrozole and Met (265 mg/kg) for 21 days. At the study end, Rha treatment restored letrozole-induced alterations in the relative ovarian weights, body weight, and relative weights of uterine and visceral adipose tissues. Histological observation showed that Rha ameliorates ovarian structure and fibrosis in PCOS. Administration of Rha reduced letrozole-induced metabolic dysfunction by ameliorating the levels of TC, TG, and HDL-C in the PCOS rats. Rha treatment also modulated the serum levels of sex hormones, which decreased T, E2, and LH and increased FSH in PCOS rats. In addition, Rha treatment modulated insulin resistance and increased gene expression of antioxidant enzymes (Cat, Sod2, Gpx3, Mgst1, Prdx3, Gsta4, Gsr, and Sod1) in the ovaries of the PCOS rats. Finally, Rha treatment appeared to increase the activity of PPAR-γ and inhibit the TGF-β1/Smad pathway in the ovaries of the PCOS rats. Our findings suggest that Rha significantly ameliorated metabolic disturbances and ovarian fibrosis in the PCOS rats. Rha perhaps is an effective compound for preventing ovarian fibrosis in the future.

Effects of total flavonoids from Eucommia ulmoides Oliv. leaves on polycystic ovary syndrome with insulin resistance model rats induced by letrozole combined with a high-fat diet

ETHNOPHARMACOLOGICAL RELEVANCE

Eucommia ulmoides Oliv. leaves are the dry leaves of Eucommia ulmoides Oliv. Modern studies have shown that Eucommia ulmoides Oliv. leaves and its extracts have many pharmacological effects, such as regulating hypothalamus pituitary ovary (HPO) axis function, estrogen like effects, correcting insulin resistance (IR), regulating lipids, and reducing weight, which are consistent with the clinical manifestations in polycystic ovary syndrome (PCOS) patients. PCOS patients often have HPO axis disorder, low estrogen, high androgen, high IR complication rate, and obesity. Previous preclinical studies have shown that total flavonoids from Eucommia ulmoides Oliv. leaves (TFEL) can improve the imbalance in sex hormone secretion in perimenopausal animal models by regulating the function of the HPO axis. Thus, it is important to understand if flavonoids are the active parts of Eucommia ulmoides Oliv. leaves that interfere with polycystic ovary syndrome with insulin resistance (PCOS-IR), and determine the regulatory role they play in sex hormones and IR?

AIM OF THE STUDY

Investigate the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway in the ovary and kisspeptin/insulin like growth factor/leptin receptor1/androgen receptor (Kiss1/IGF-1/LEPR/AR) in the HPO axis to determine the mechanism of TFEL intervention in a rat model of PCOS-IR model rats.

MATERIALS AND METHODS

A rat model of PCOS-IR was established using a high-fat diet (49 d) combined with letrozole (1 mg/kg·d, for 28 d). Then, metformin (300 mg/kg·d) and TFEL (220 mg/kg·d, 110 mg/kg·d, and 55 mg/kg·d) were administered continuously for 21 days. At the end of the experiment, samples were taken and the related indexes were measured.

RESULTS

TFEL reduced the body weight, Lee's index, ovarian index, ovarian area and ovarian volume, increased serum E2, SHBG levels and ISI, decreased serum levels of T, LEP, INS, and FBG (whole blood), and reduced the HOMA-IR in rats with PCOS-IR. TFEL downregulate Kiss1, IGF-1, and AR in the arcuate nucleus of hypothalamus, and upregulate Kiss1, downregulate IGF-1 and AR in the pituitary gland, and upregulate Kiss1, downregulate IGF-1, LEPR, and AR in the ovary of rats with PCOS-IR. TFEL could downregulate p-IRS-1Ser307, upregulate IRS-1, p-IRS-1Tyr895, PI3Kp85α, p-PI3Kp85α, AKT, p-AKT, and GLUT4 in the ovary, and ameliorated histopathological changes in the ovary and pancreas of rats with PCOS-IR.

CONCLUSION

TFEL can inhibit ovarian hyperplasia, regulate disorders of glucose and lipid metabolism and improve the secretion of sex hormones, by regulating the expression of PI3K/AKT signaling pathway-related proteins in the ovary and Kiss1/IGF-1/LEPR/AR in the HPO axis.

Plasma testosterone and arrhythmic events in male patients with arrhythmogenic right ventricular cardiomyopathy

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with life-threatening ventricular arrhythmia and progressive ventricular dysfunction. Previous studies suggested that sex hormones play an important role in the onset and prognosis of ARVC. This study aimed to investigate the role of testosterone in predicting major adverse cardiac events in the Chinese ARVC cohort.

METHODS AND RESULTS

Ninety-nine ARVC patients (median age, 40 years; 70.7% male) and 96 healthy controls (median age, 41 years; 62.5% male) were enrolled. The circulating levels of testosterone were measured by enzyme-linked immunosorbent assays (ELISA). The median follow-up time of all ARVC male patients was 17 months (interquartile range/IQR 9-29). Cox proportional hazards regression was used to analyse the effect of plasma testosterone and other well-described risk factors on malignant arrhythmic events in male ARVC patients. The male ARVC patients had significantly elevated levels of total testosterone [TT, 6.390 (4.438-8.768) ng/mL vs. 3.617 (2.073-4.479) ng/mL, P < 0.0001, data shown as the median with IQR], bioavailable testosterone [BT, 4.11 (1.990-6.545) ng/mL vs. 1.32 (0.7965-2.0350) ng/mL, P < 0.0001, median with IQR], and free testosterone [FT, 0.2055 (0.1000-0.4073) ng/mL vs. 0.0768 (0.0405-0.1105) ng/mL, P < 0.0001, median with IQR] than healthy male volunteer, whereas no differences were observed among female counterparts. There was no significant correlation between the baseline clinical characteristics and testosterone levels in male ARVC patients (Spearman's correlation test, P > 0.05). During the follow-up, the levels of testosterone were higher in male patients who experienced malignant arrhythmic events (N = 22) than in those who did not (N = 25) [TT, 9.034 (7.222-15.370) ng/mL vs. 4.633 (3.363-6.375) ng/mL, P < 0.001; BT, 7.485 (2.070-9.163) ng/mL vs. 3.300 (1.685-4.690) ng/mL, P < 0.05; FT, 0.453 (0.221-0.758) ng/mL vs. 0.161 (0.075-0.337) ng/mL P < 0.05, data expressed as median (IQR) and adjusted by Dunn's multiple comparisons test], whereas such distinction was not observed among patients with significant structural progression events (N = 16). Through multivariable adjustments, the Cox regression analysis showed the level of plasma total testosterone (HR = 1.325, 95% confidence interval = 1.171-1.498, P < 0.001) was an independent predictor for malignant arrhythmic events.

CONCLUSIONS

The levels of plasma testosterone in ARVC male patients are higher than those in healthy males. Testosterone level, without relation to the baseline cardiac function and future significant structural progression events, is a strong predictor of future adverse arrhythmic events in male patients with ARVC. Therefore, our results suggest that testosterone may be a useful biomarker in arrhythmic risk prediction in the ARVC.