The mitochondrial profile in women with polycystic ovary syndrome: impact of exercise

Resveratrol ameliorates mitochondrial biogenesis and reproductive outcomes in women with polycystic ovary syndrome undergoing assisted reproduction: a randomized, triple-blind, placebo-controlled clinical trial

BACKGROUND

This study was designed to examine the effect of resveratrol on mitochondrial biogenesis, oxidative stress (OS), and assisted reproductive technology (ART) outcomes in individuals with polycystic ovary syndrome (PCOS).

METHODS

Fifty-six patients with PCOS were randomly assigned to receive 800 mg/day of resveratrol or placebo for 60 days. The primary outcome was OS in follicular fluid (FF). The secondary outcome involved assessing gene and protein expression related to mitochondrial biogenesis, mitochondrial DNA (mtDNA) copy number, and adenosine triphosphate (ATP) content in granulosa cells (GCs). ART outcomes were evaluated at the end of the trial.

RESULTS

Resveratrol significantly reduced the total oxidant status (TOS) and oxidative stress index (OSI) in FF (P = 0.0142 and P = 0.0039, respectively) while increasing the total antioxidant capacity (TAC) (P < 0.0009). Resveratrol consumption also led to significant increases in the expression of critical genes involved in mitochondrial biogenesis, including peroxisome proliferator-activated receptor gamma coactivator (PGC-1α) and mitochondrial transcription factor A (TFAM) (P = 0.0032 and P = 0.0003, respectively). However, the effect on nuclear respiratory factor 1 (Nrf-1) expression was not statistically significant (P = 0.0611). Resveratrol significantly affected sirtuin1 (SIRT1) and PGC-1α protein levels (P < 0.0001 and P = 0.0036, respectively). Resveratrol treatment improved the mtDNA copy number (P < 0.0001) and ATP content in GCs (P = 0.0014). Clinically, the resveratrol group exhibited higher rates of oocyte maturity (P = 0.0012) and high-quality embryos (P = 0.0013) than did the placebo group. There were no significant differences between the groups in terms of chemical or clinical pregnancy rates (P > 0.05).

CONCLUSIONS

These findings indicate that resveratrol may be a promising therapeutic agent for patients with PCOS undergoing assisted reproduction.

TRIAL REGISTRATION NUMBER

http://www.irct.ir ; IRCT20221106056417N1; 2023 February 09.

Exercise in the management of polycystic ovary syndrome: A position statement from Exercise and Sport Science Australia

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine condition amongst females of reproductive age, leading to lifelong cardiometabolic, reproductive, psychological, and dermatologic symptoms as well as a reduced quality of life. Lifestyle interventions, which can include structured exercise programmes delivered by appropriately trained exercise professionals such as clinical exercise physiologists, are considered first-line strategies in PCOS management due to their therapeutic effects on various health outcomes and quality of life. This position statement builds on the 2023 International Evidence-based Guideline for the Assessment and Management of PCOS and describes the role of the exercise professional in the context of the multidisciplinary care team which includes physicians and allied health professionals. This position statement aims to equip exercise professionals with a broad understanding of the pathophysiology of PCOS, how it is diagnosed and managed in clinical practice, and evidence- and consensus-based recommendations for physical activity and exercise in PCOS management. In line with the physical activity recommendations for the general public, individuals with PCOS should aim to undertake between 150 to 300min of moderate-intensity or 75 to 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week. Additionally, muscle-strengthening activities on two non-consecutive days per week are recommended to maintain health and prevent weight gain. For further health benefits and to achieve modest weight loss, individuals with PCOS should aim for a minimum of 250min of moderate-intensity or 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week, plus muscle-strengthening activities on two non-consecutive days per week. Adolescents with PCOS should aim for a minimum of 60min moderate- to vigorous-intensity activity each day, incorporating muscle- and bone-strengthening activities three times per week. Finally, exercise professionals should consider the significant psychological burden, including weight stigma, and the high prevalence of comorbidities amongst individuals with PCOS and take appropriate measures to deliver safe and efficacious exercise interventions.

Validation of mitochondrial biomarkers and immune dynamics in polycystic ovary syndrome

PROBLEM

Polycystic ovary syndrome (PCOS), a prevalent endocrine-metabolic disorder, presents considerable therapeutic challenges due to its complex and elusive pathophysiology.

METHOD OF STUDY

We employed three machine learning algorithms to identify potential biomarkers within a training dataset, comprising GSE138518, GSE155489, and GSE193123. The diagnostic accuracy of these biomarkers was rigorously evaluated using a validation dataset using area under the curve (AUC) metrics. Further validation in clinical samples was conducted using PCR and immunofluorescence techniques. Additionally, we investigate the complex interplay among immune cells in PCOS using CIBERSORT to uncover the relationships between the identified biomarkers and various immune cell types.

RESULTS

Our analysis identified ACSS2, LPIN1, and NR4A1 as key mitochondria-related biomarkers associated with PCOS. A notable difference was observed in the immune microenvironment between PCOS patients and healthy controls. In particular, LPIN1 exhibited a positive correlation with resting mast cells, whereas NR4A1 demonstrated a negative correlation with monocytes in PCOS patients.

CONCLUSION

ACSS2, LPIN1, and NR4A1 emerge as PCOS-related diagnostic biomarkers and potential intervention targets, opening new avenues for the diagnosis and management of PCOS.

Health-related physical fitness in women with polycystic ovary syndrome versus controls: a systematic review and meta-analysis

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrinopathy associated with cardiometabolic dysfunction.

PURPOSE

(1) To compare HRPF indices, including cardiorespiratory fitness (CRF), muscle strength, and muscle endurance, between women with and without PCOS (i.e., controls). (2) To explore the impact of moderating factors, i.e., insulin sensitivity, androgen levels, physical activity levels, and body mass index, on these indices.

METHODS

Articles comparing HRPF between PCOS and control groups were identified until February 27th, 2022. Random-effects meta-analyses were conducted and moderating factors were explored with subgroup and meta-regression analyses.

RESULTS

Twenty studies were included. Compared to controls, CRF was lower in women with PCOS (n = 15, - 0.70 [- 1.35, - 0.05], P = 0.03, I2 = 95%). Meta-regression analyses demonstrated that fasting insulin (P = 0.004) and homeostatic model assessment of insulin resistance (P = 0.006) were negatively associated with CRF, while sex-hormone binding globulin levels (P = 0.003) were positively associated. Absolute muscle strength was not different between PCOS and controls (n = 7, 0.17 [- 0.10, 0.45], P = 0.22, I2 = 37%). One study evaluated muscle endurance and reported lower core endurance in PCOS subjects compared to controls.

CONCLUSION

These data suggest that PCOS may be associated with impaired CRF. It remains unclear whether muscle strength and endurance differ between women with PCOS and controls. As this data set was limited by a small sample size, potential for bias, and inconsistent findings, additional studies accounting for the heterogeneous presentation of PCOS as well as improved matching between PCOS and controls for characteristics known to affect HRPF would help elucidate the impact of PCOS on indices of HRPF.

PROSPERO REGISTRATION NUMBER

CRD42020196380.

Adipose Tissue Dysfunction in Polycystic Ovary Syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is a complex genetic trait and the most common endocrine disorder of women, clinically evident in 5% to 15% of reproductive-aged women globally, with associated cardiometabolic dysfunction. Adipose tissue (AT) dysfunction appears to play an important role in the pathophysiology of PCOS even in patients who do not have excess adiposity.

METHODS

We undertook a systematic review concerning AT dysfunction in PCOS, and prioritized studies that assessed AT function directly. We also explored therapies that targeted AT dysfunction for the treatment of PCOS.

RESULTS

Various mechanisms of AT dysfunction in PCOS were identified including dysregulation in storage capacity, hypoxia, and hyperplasia; impaired adipogenesis; impaired insulin signaling and glucose transport; dysregulated lipolysis and nonesterified free fatty acids (NEFAs) kinetics; adipokine and cytokine dysregulation and subacute inflammation; epigenetic dysregulation; and mitochondrial dysfunction and endoplasmic reticulum and oxidative stress. Decreased glucose transporter-4 expression and content in adipocytes, leading to decreased insulin-mediated glucose transport in AT, was a consistent abnormality despite no alterations in insulin binding or in IRS/PI3K/Akt signaling. Adiponectin secretion in response to cytokines/chemokines is affected in PCOS compared to controls. Interestingly, epigenetic modulation via DNA methylation and microRNA regulation appears to be important mechanisms underlying AT dysfunction in PCOS.

CONCLUSION

AT dysfunction, more than AT distribution and excess adiposity, contributes to the metabolic and inflammation abnormalities of PCOS. Nonetheless, many studies provided contradictory, unclear, or limited data, highlighting the urgent need for additional research in this important field.

Acyl-Carnitines Exert Positive Effects on Mitochondrial Activity under Oxidative Stress in Mouse Oocytes: A Potential Mechanism Underlying Carnitine Efficacy on PCOS

Carnitines play a key physiological role in oocyte metabolism and redox homeostasis. In clinical and animal studies, carnitine administration alleviated metabolic and reproductive dysfunction associated with polycystic ovarian syndrome (PCOS). Oxidative stress (OS) at systemic, intraovarian, and intrafollicular levels is one of the main factors involved in the pathogenesis of PCOS. We investigated the ability of different acyl-carnitines to act at the oocyte level by counteracting the effects of OS on carnitine shuttle system and mitochondrial activity in mouse oocytes. Germinal vesicle (GV) oocytes were exposed to hydrogen peroxide and propionyl-l-carnitine (PLC) alone or in association with l-carnitine (LC) and acetyl-l-carnitine (ALC) under different conditions. Expression of carnitine palmitoyltransferase-1 (Cpt1) was monitored by RT-PCR. In in vitro matured oocytes, metaphase II (MII) apparatus was assessed by immunofluorescence. Oocyte mitochondrial respiration was evaluated by Seahorse Cell Mito Stress Test. We found that Cpt1a and Cpt1c isoforms increased under prooxidant conditions. PLC alone significantly improved meiosis completion and oocyte quality with a synergistic effect when combined with LC + ALC. Acyl-carnitines prevented Cpt1c increased expression, modifications of oocyte respiration, and ATP production observed upon OS. Specific effects of PLC on spare respiratory capacity were observed. Therefore, carnitine supplementation modulated the intramitochondrial transfer of fatty acids with positive effects on mitochondrial activity under OS. This knowledge contributes to defining molecular mechanism underlying carnitine efficacy on PCOS.

Insulin resistance in polycystic ovary syndrome across various tissues: an updated review of pathogenesis, evaluation, and treatment

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by chronic ovulation dysfunction and overabundance of androgens; it affects 6-20% of women of reproductive age. PCOS involves various pathophysiological factors, and affected women usually have significant insulin resistance (IR), which is a major cause of PCOS. IR and compensatory hyperinsulinaemia have differing pathogeneses in various tissues, and IR varies among different PCOS phenotypes. Genetic and epigenetic changes, hyperandrogenaemia, and obesity aggravate IR. Insulin sensitization drugs are a new treatment modality for PCOS. We searched PubMed, Google Scholar, Elsevier, and UpToDate databases in this review, and focused on the pathogenesis of IR in women with PCOS and the pathophysiology of IR in various tissues. In addition, the review provides a comprehensive overview of the current progress in the efficacy of insulin sensitization therapy in the management of PCOS, providing the latest evidence for the clinical treatment of women with PCOS and IR.

OXIDATIVE STRESS AND REPRODUCTIVE FUNCTION: Oxidative stress in polycystic ovary syndrome

In brief

A genetic, epigenetic, and environmental association exists between oxidative stress (OS) and polycystic ovary syndrome (PCOS), expressed in a multifaceted clinical profile. This review summarizes and discusses the role of OS in the pathogenesis of PCOS syndrome, focusing on metabolic, reproductive, and cancer complications.

Abstract

Oxidative stress (OS), an imbalance between oxidants and antioxidants in cells, is one of many factors playing essential roles in the pathogenesis of polycystic ovary syndrome (PCOS). PCOS is described mainly as a disproportion of reproductive hormones, leading to chronic anovulation and infertility in women. Interestingly, OS in PCOS may be associated with many disorders and diseases. This review focuses on characteristic markers of OS in PCOS and the relationship between OS and PCOS related to insulin resistance (IR), hyperandrogenemia, obesity, chronic inflammation, cardiovascular diseases, and cancer. Interestingly, in patients with PCOS, an increase in oxidative status and insufficient compensation of the increase in antioxidant status before any cardiovascular complications are observed. Moreover, free radicals promote carcinogenesis in PCOS patients. However, despite these data, it has not been established whether oxygen stress influences PCOS development or a secondary disorder resulting from hyperglycemia, IR, and cardiovascular and cancer complications in women.

Modulation of the Inflammatory Response in Polycystic Ovary Syndrome (PCOS)-Searching for Epigenetic Factors

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. Despite its incidence, the syndrome is poorly understood and remains underdiagnosed, and female patients are diagnosed with a delay. The heterogenous nature of this complex disorder results from the combined occurrence of genetic, environmental, endocrine, and behavioral factors. Primary clinical manifestations of PCOS are derived from the excess of androgens (anovulation, polycystic ovary morphology, lack of or scanty, irregular menstrual periods, acne and hirsutism), whereas the secondary manifestations include multiple metabolic, cardiovascular, and psychological disorders. Dietary and lifestyle factors play important roles in the development and course of PCOS, which suggests strong epigenetic and environmental influences. Many studies have shown a strong association between PCOS and chronic, low-grade inflammation both in the ovarian tissue and throughout the body. In the vast majority of PCOS patients, elevated values of inflammatory markers or their gene markers have been reported. Development of the vicious cycle of the chronic inflammatory state in PCOS is additionally stimulated by hyperinsulinemia and obesity. Changes in DNA methylation, histone acetylation and noncoding RNA levels are presented in this review in the context of oxidative stress, reactive oxygen species, and inflammatory signaling in PCOS. Epigenetic modulation of androgenic activity in response to inflammatory signaling is also discussed.

Metabolic and Molecular Mechanisms of Diet and Physical Exercise in the Management of Polycystic Ovarian Syndrome

Polycystic ovary syndrome (PCOS) is an endocrine systemic disorder mainly characterized by a hormonal and metabolic disbalance that leads to oligo/anovulation, hyperandrogenism and the formation of ovarian cysts. Despite the progress that has been reached in its diagnosis and management, little is known about the molecular mechanisms and signaling pathways underlying the pathogenic mechanisms. In this sense, recent research has suggested that the influence of multiple factors, including age, environment, lifestyle and the disease state environment can change the clinical presentation of PCOS via epigenetic modifications. Variants in the genes encoding for proteins involved in steroidogenesis and glucose homeostasis play a crucial role in the development of the disease. Other genes involved in inflammation and cell proliferation seem to undergo an epigenetic control. Moreover, lifestyle factors influence the PCOS course and prognosis, including diet and physical activity, which are fundamental in reducing oxidative stress, inflammation and in improving metabolic and hormonal parameters. In the present review, literature evidence on molecular and epigenetic mechanisms related to PCOS etiology will be discussed, with a particular attention on the positive influence of diet and physical activity as nonpharmacological ways of intervention in the management of the disease.