Potential Role of Quercetin in Polycystic Ovary Syndrome and Its Complications: A Review

Bridging gap in treatment of polycystic ovarian syndrome through drug repurposing: what we achieved and where we are?

Polycystic ovarian syndrome (PCOS) is one of the chief causes of infertility in women of reproductive age. Several drugs belonging to the oral contraceptive class have been approved for the treatment of PCOS. Nonetheless, the capability to target only a few symptoms of PCOS and fatal side effects are key hurdles to their use. Therefore, repurposing existing drugs can be promising in managing PCOS efficiently. Drugs from different pharmacological classes like antidiabetics (metformin, rosiglitazone, pioglitazone, and semaglutide), statins (simvastatin and atorvastatin), antiandrogen drugs (finasteride and flutamide), etc. demonstrated significant potential in managing PCOS. The present review offers a comprehensive overview of all the medications examined as potential repurposed options for the efficient treatment of PCOS. The pathogenesis of PCOS, existing therapies for PCOS and their challenges, drug repurposing and its significance is also explained. The small-molecular drugs from various pharmacological classes and different phytoceuticals repurposed against PCOS are discussed along with their anti-PCOS activity mechanisms. Moreover, novel drug targets responsible for PCOS and opportunities for drug repurposing are briefed. The repurposed drugs in clinical trials for PCOS and drug repurposing challenges are discussed. Thus, drug repurposing can serve as a potential way to effectively treat PCOS, reducing the extent of infertility and improving the quality of life of women.

Mechanism of action of quercetin in regulating cellular autophagy in multiple organs of Goto-Kakizaki rats through the PI3K/Akt/mTOR pathway

Objective

This experimental study investigated the protective function of quercetin on the liver, spleen, and kidneys of Goto-Kakizaki (GK) rats and explores its mechanism of action on autophagy-related factors and pathways.

Materials and methods

GK rats were randomly divided into three groups: DM, DM + L-Que, and DM + H-Que, with age-matched Wistar rats serving as the control group. The control and DM groups were gavaged with saline, and the quercetin-treated group was gavaged with quercetin for 8 weeks each. Weekly blood glucose levels were monitored. Upon conclusion of the experiment, blood samples were gathered for lipid and hepatic and renal function analyses. The histopathologic morphology and lipid deposition in rats were examined. Disease-related targets were identified using molecular docking methods and network pharmacology analysis. Subsequently, immunohistochemical analysis was performed, followed by Western blotting to evaluate the levels of autophagy-related proteins and proteins in the AKT/PI3K/mTOR pathway, as well as their phosphorylation levels.

Results

The results showed that, compared with the control group, the DM group exhibited significant increases in blood glucose, serum liver and kidney markers, liver fat vacuoles, and inflammatory cell infiltration. Immunohistochemistry (IHC) results indicated that quercetin reduced the extensive expression of AKT, P62, and mTOR in the liver and spleen of diabetic rats. The expression of autophagy and pathway-related proteins, such as P62, PI3K, P-PI3K, Akt, P-AKT, mTOR, and P-mTOR, was upregulated, while the expression of LC3A/LC3B, Beclin-1, Pink-1, and Parkin was downregulated. Conversely, the quercetin group showed a reduction in liver and kidney injury serum markers by decreasing lipid deposition and cell necrosis, indicating that quercetin has protective effects on the liver, spleen, and kidneys of GK rats. Additionally, in the quercetin group, the expression of autophagy and pathway-related proteins such as LC3A/LC3B, Beclin-1, Pink-1, and Parkin was upregulated, while the expression of P62, PI3K, P-PI3K, Akt, P-AKT, mTOR, and P-mTOR was downregulated, with statistically significant correlations.

Conclusion

Quercetin markedly ameliorates liver, spleen, and kidney damage in GK rats, potentially through the inhibition of the PI3K/Akt/mTOR pathway, promoting autophagy. This research offers a rationale to the therapeutic potential of quercetin in mitigating organ damage associated with diabetes.

Flavonoid Supplementation Is Beneficial for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis

CONTEXT

Polycystic ovary syndrome (PCOS) is a prevalent hormonal imbalance that predominantly affects women in their reproductive years. Previous studies have yielded conflicting conclusions.

OBJECTIVE

This is an updated meta-analysis aiming to explore the connection between flavonoid supplementation and PCOS.

DATA SOURCES

Seven databases were searched: Cochrane Library, PubMed, Web of Science, Embase, Wanfang, China Science and Technology Journal, and China National Knowledge Infrastructure, spanning from their inception to April 15, 2024.

DATA EXTRACTION

Two authors independently searched the databases using the search terms.

DATA ANALYSIS

Following strict inclusion criteria, 8 papers were ultimately included. This updated meta-analysis suggests that flavonoid supplementation could enhance follicular development, promote the proliferation and differentiation of follicular granulosa cells, elevate estradiol levels, and mitigate testosterone, C-reactive protein, and ovarian index levels.

CONCLUSION

This analysis suggests that dietary flavonoids could potentially alleviate symptoms associated with PCOS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022382912.

Therapeutic effects and molecular mechanisms of quercetin in gynecological disorders

Quercetin is a representative flavonoid that is widely present in fruits, herbs, and vegetables. It is also an important active core component in traditional Chinese medicines. As an important flavonoid, quercetin has various properties and exerts antioxidant, anti-inflammatory, and cardioprotective effects. The public interest in quercetin is increasing, and quercetin has been used to prevent or treat numerous of diseases, such as polycystic ovary syndrome (PCOS), cancer, autoimmune diseases and chronic cardiovascular diseases, in clinical experiments and animal studies due to its powerful antioxidant properties and minimal side effects. Quercetin exerts marked pharmacological effects on gynecological disorders; however, there have been no reviews about the potential health benefits of quercetin in the context of gynecological disorders, including PCOS, premature ovary failure (POF), endometriosis (EM), ovarian cancer (OC), cervical cancer (CC) and endometrial carcinoma (EC). Thus, this review aimed to summarize the biological effects of quercetin on gynecological disorders and its mechanisms.

Exploring the Therapeutic Potential of Natural Products in Polycystic Ovarian Syndrome (PCOS): A Mini-Review of Lipid Profile, Blood Glucose, and Ovarian Histological Improvements

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women that is characterized by fluid-filled sacs in the ovaries and various symptoms, including high androgen levels, endometrial irregularities, and cysts. Although the main cause of PCOS remains unknown, it has been linked to genetic, endocrine, and metabolic factors, and there are several treatment options, including lifestyle modifications, medications, and surgery. Natural products such as medicinal plants and fruits are being explored as potential treatments for PCOS because of their bioactive compounds with pharmacological effects related to antioxidant, antimicrobial, anticancer, and antidiabetic properties. Some of these compounds improve insulin sensitivity, reduce inflammation, and enhance glucose metabolism, thereby benefiting patients with PCOS. This mini-review examined the effects of natural products on PCOS, including their effects on ovarian histological changes, blood glucose, sex hormones, and lipid profiles, based on animal and human studies. This study suggests that the use of natural products as complementary medicines can be a promising resource for the development of effective therapeutics for PCOS; however, further research is needed to fully understand their benefits.

Signaling pathways and targeted therapeutic strategies for polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age. Although promising strides have been made in the field of PCOS over the past decades, the distinct etiologies of this syndrome are not fully elucidated. Prenatal factors, genetic variation, epigenetic mechanisms, unhealthy lifestyles, and environmental toxins all contribute to the development of this intricate and highly heterogeneous metabolic, endocrine, reproductive, and psychological disorder. Moreover, interactions between androgen excess, insulin resistance, disruption to the hypothalamic-pituitary-ovary (HPO) axis, and obesity only make for a more complex picture. In this review, we investigate and summarize the related molecular mechanisms underlying PCOS pathogenesis from the perspective of the level of signaling pathways, including PI3K/Akt, TGF-β/Smads, Wnt/β-catenin, and Hippo/YAP. Additionally, this review provides an overview of prospective therapies, such as exosome therapy, gene therapy, and drugs based on traditional Chinese medicine (TCM) and natural compounds. By targeting these aberrant pathways, these interventions primarily alleviate inflammation, insulin resistance, androgen excess, and ovarian fibrosis, which are typical symptoms of PCOS. Overall, we hope that this paper will pave the way for better understanding and management of PCOS in the future.

Quercetin action on health and female reproduction in mammals

This paper reviews the current information concerning availability, metabolism of quercetin, its effects on physiological processes and illnesses with focus on the effects, mechanisms of action and areas of possible application of quercetin in control of female reproductive processes, prevention and treatment of their disorders in mammals.The available information demonstrated the ability of quercetin and its analogues to inhibit proliferation and to promote apoptosis, to activate regenerative processes, to treat immune, inflammatory, cardiovascular, neurodegenerative, gastric and metabolic disorders and cancer, to suppress microorganisms, to protect bones and liver, to relieve pain, to improve physical and mental performance, and to prolong life span.The positive influences of quercetin on mammalian female reproductive processes are well documented. It can promote ovarian follicullo- and oogenesis, improve quality of oocytes and embryos, increase fecundity in various species. These effects can be mediated by changes in pituitary and ovarian hormones, growth factors and cytokines, in their receptors and post-receptory signaling pathways. Due to these effect, quercetin can be applicable as biostimulator of reproduction, for prevention, mitigation and treatment of several female reproductive disorders, as well as to increase resistance of female reproductive system to adverse effect of chemotherapy, temperature stress and environmental contaminants.

Effect of quercetin on steroidogenesis and folliculogenesis in ovary of mice with experimentally-induced polycystic ovarian syndrome

Introduction

Polycystic Ovary syndrome (PCOS) affects the health of many women around theworld. Apart from fundamental metabolic problems connected to PCOS, focus of our study is on the role of quercetin on genes relevant to steroidogenesis and folliculogenesis.

Methods

Eighteen mature parkes strain mice (4-5 weeks old) weighing18-21 g were randomly divided into three groups of six each as follows: Group I serves as the control and was given water and a regular chow diet ad lib for 66 days; group II was given oral gavage administration of letrozole (LETZ) (6 mg/kgbw) for 21 days to induce PCOS and was left untreated for 45 days; For three weeks, Group III received oral gavage dose of LETZ (6 mg/kg), after which it received Quercetin (QUER) (125 mg/kg bw orally daily) for 45 days.

Results

In our study we observed that mice with PCOS had irregular estrous cycle with increased LH/FSH ratio, decreased estrogen level and decline in expression of Kitl, Bmp1, Cyp11a1, Cyp19a1, Ar, lhr, Fshr and Esr1 in ovary. Moreover, we observed increase in the expression of CYP17a1, as well as increase in cholesterol, triglycerides, testosterone, vascular endothelial growth factor VEGF and insulin levels. All these changes were reversed after the administration of quercetin in PCOS mice.

Discussion

Quercetin treatment reversed the molecular, functional and morphological abnormalities brought on due to letrozole in pathological and physiological setting, particularly the issues of reproduction connected to PCOS. Quercetin doesn't act locally only but it acts systematically as it works on Pituitary (LH/FSH)- Ovary (gonad hormones) axis. the Side effects of Quercetin have to be targeted in future researches. Quercetin may act as a promising candidate for medical management of human PCOS.

A Descriptive Review of the Action Mechanisms of Berberine, Quercetin and Silymarin on Insulin Resistance/Hyperinsulinemia and Cardiovascular Prevention

Insulin resistance (IR) and the associated hyperinsulinemia are early pathophysiological changes which, if not well treated, can lead to type 2 diabetes, endothelial dysfunction and cardiovascular disease. While diabetes care is fairly well standardized, the prevention and treatment of IR lacks a single pharmaceutical approach and many lifestyle and dietary interventions have been proposed, including a wide range of food supplements. Among the most interesting and well-known natural remedies, alkaloid berberine and the flavonol quercetin have particular relevance in the literature, while silymarin-the active principle of the Silybum marianum thistle-was traditionally used for lipid metabolism disorders and to sustain liver function. This review describes the major defects of insulin signaling leading to IR and the main properties of the three mentioned natural substances, their molecular targets and synergistic action mechanisms. The actions of berberine, quercetin and silymarin are partially superimposable as remedies against reactive oxygen intermediates generated by a high-lipid diet and by NADPH oxidase, which is triggered by phagocyte activation. Furthermore, these compounds inhibit the secretion of a battery of pro-inflammatory cytokines, modulate intestinal microbiota and are especially able to control the various disorders of the insulin receptor and post-receptor signaling systems. Although most of the evidence on the effects of berberine, quercetin and silymarin in modulating insulin resistance and preventing cardiovascular disease derive from experimental studies on animals, the amount of pre-clinical knowledge strongly suggests the need to investigate the therapeutic potential of these substances in human pathology.

Effects of quercetin on granulosa cells from prehierarchical follicles by modulating MAPK signaling pathway in chicken

Quercetin (Que), widely found in a huge variety of plants, plays important roles in ovarian function. However, to data, there have been no reports about Que regulating granulosa cells (GCs) in prehierarchical follicles in chicken. Herein, GCs from follicles diameter from 4 to 8 mm in chicken were treated by Que in vitro culture to investigate how Que exerts its effect on follicular development. GCs treated by Que in concentrations of 10, 100, and 1,000 ng/mL were tested for cell proliferation and progesterone secretion. Eight cDNA libraries were constructed from GCs (4 samples per group) to explore transcriptome expression changes. The role of the MAPK/ERK signaling pathway was validated in this process. Treatment with 100 and 1,000 ng/mL levels of Que significantly promoted cell proliferation and progesterone secretion (P < 0.05). RNA-seq analysis data showed that 402 and 263 differentially expressed genes (DEGs) were up- and down-regulated, respectively. Functional enrichment analysis that the pathways related to follicular development included biosynthesis of amino acids, MAPK signaling pathway, and calcium signaling pathway. Notably, the function exerted in GCs of the different levels of Que was associated with the suppression of the MAPK pathway. In conclusion, our results proved that low levels of Que could promote MAPK signaling pathway, but high levels of Que inhibit MAPK signaling pathway in GCs from the prehierarchical follicles, promote cell proliferation and progesterone secretion, and benefit follicle selection.

Bioactive compounds in childhood obesity and associated metabolic complications: Current evidence, controversies and perspectives

Obesity represents the most frequent chronic disease among children worldwide, with a significant global burden on society. Metabolically unhealthy obesity (MUO) can affect children since their first years of life, and novel therapeutic strategies to tackle metabolic complications are under investigation. This review focuses on bioactive compounds and their possible beneficial effects on obesity, particularly omega-3, docosahexaenoic acid, vitamin D, biotics, polysaccharide macromolecules, polyphenols, inositols, alpha lipoic acid, and bromelaine. Our aim is to summarize current evidence about bioactive compounds in the treatment of obesity, highlighting recent findings on their use in children and adolescents. Most studied molecules are omega-3 and vitamin D, despite the heterogeneity between the studies. Moreover, given the emerging interest in the gut-brain axis in the link between metabolic health and microbiota, various studies on prebiotics, probiotics, synbiotics, postbiotics and polysaccharide macromolecules have been considered. Some preclinical studies seem to highlight a possible role of the polyphenols, even if their clinical evidence is still discussed. Lastly, we describe possible effects of inositols and alpha-lipoic acid. Despite some dietary supplements seem to be promising in overweight subjects, only in a few of them a dose/response efficacy has been found in the pediatric age. Innovative, well-designed and targeted clinical trials are then needed to prove the beneficial effects of these compounds that could support the standard behavioral therapy for obesity.

Quercetin and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a reproductive endocrine disease, and results to opsomenorrhea or amenorrhea, hairy, acne, acanthosis, infertility, abortion. In the long term, PCOS may also increase the risk of endometrial cancer, diabetes, hypertension, dyslipidemia and other diseases. Till now there is no specific drug for PCOS due to the unclearness of the cause and pathogenesis, as current treatments for PCOS only target certain symptoms. Quercetin (QUR) is a flavonoid drug widely found in Chinese herbal medicines, fruits, leaves, vegetables, seeds and plants roots. Studies on other diseases have found that QUR has anti-oxidant, anti-inflammatory, anti-insulin resistance, anti-cancer and other effects. Some studies have shown that serum testosterone (T), luteinizing hormone (LH), the LH/follicule-stimulating hormone (FSH) ratio, fasting glucose, fasting insulin, HOMA-IR and lipid levels are reduced in PCOS patients with QUR treatment. However, the mechanisms of QUR in PCOS patients have not been completely elucidated. In this review, we retrospect the basic characteristics of QUR, and in vitro studies, animal experiments and clinical trials of QUR and plant extracts containing QUR in the treatment of PCOS. We also summarized the effects and mechanism of QUR in ovarian cells in vitro and PCOS model rats, the changes in relevant parameters after QUR administration in PCOS patients, and its potentially therapeutic applications.

The impact of herbal medicine in regulating intestinal flora on female reproductive disorders

As an important part of the human intestinal microecology, the intestinal flora is involved in a number of physiological functions of the host. Several studies have shown that imbalance of intestinal flora and its regulation of the intestinal barrier, intestinal immune response, and intestinal flora metabolites (short-chain fatty acids and bile acids) can affect the development and regression of female reproductive disorders. Herbal medicine has unique advantages in the treatment of female reproductive disorders such as polycystic ovary syndrome, endometriosis and premature ovarian insufficiency, although its mechanism of action is still unclear. Therefore, based on the role of intestinal flora in the occurrence and development of female reproduction-related diseases, the progress of research on the diversity, structure and composition of intestinal flora and its metabolites regulated by botanical drugs, Chinese herbal formulas and active ingredients of Chinese herbal medicines is reviewed, with a view to providing reference for the research on the mechanism of action of Chinese herbal medicines in the treatment of female reproductive disorders and further development of new herbal medicines.