Myo-inositol and D-chiro-inositol (40:1) reverse histological and functional features of polycystic ovary syndrome in a mouse model

Update on the combination of myo-inositol/d-chiro-inositol for the treatment of polycystic ovary syndrome

In this article, we present a narrative review on the use of inositol in the treatment of polycystic ovary syndrome (PCOS). Of the different inositols that exist, only myo-inositol (MYO) and D-chiro inositol (DCI) have been studied in the treatment of PCOS. The results of the studies show that there is insufficient or controversial evidence to recommend the use of DCI alone, while MYO alone shows positive results and, above all, the MYO/DCI combination is effective when used at a ratio of at least 40:1, but there is enough rationale to further study ratios such as 66:1 to 100:1 as other possible effective combinations.

Myo-Inositol and Its Derivatives: Their Roles in the Challenges of Infertility

Myo-inositol (MYO) and D-chiro-inositol (DCI) are the two most significant isomeric forms of inositol, playing a critical role in intracellular signaling. MYO is the most abundant form of inositol in nature; DCI is produced from MYO through epimerization by an insulin-dependent enzyme. Recently, it has been demonstrated that inositol may influence oocyte maturation and improve intracellular Ca2+ oscillation in the oocytes, and it has been proposed as a potential intervention for restoring spontaneous ovulation. The MYO concentration in human follicular fluid is considered a bioindicator of oocyte quality. In the ovary, DCI modulates the activity of aromatase, thus regulating androgen synthesis. Under physiological conditions, the MYO/DCI ratio is maintained at 40:1 in plasma. In women with PCOS, the MYO/DCI ratio is lowered to 0:2:1, contributing to elevated androgen production. By regulating FSH signaling, MYO administration increases the number of high-quality embryos available for transfer in poor responder patients. Finally, by acting downstream to insulin signaling, inositol administration during pregnancy may represent a novel strategy for counteracting gestational diabetes. These findings show that diet supplementation with inositol may be a promising strategy to address female infertility and sustain a healthy pregnancy.

Inositols and female reproduction disorders: a consensus statement from the working group of the Club of the Italian Society of Endocrinology (SIE)-Women's Endocrinology

PURPOSE

To provide the latest scientific knowledge on the efficacy of inositols for improving reproductive disorders in women with and without polycystic ovary syndrome (PCOS) and to reach a consensus on their potential use through a Delphi-like process.

METHODS

A panel of 17 endocrinologists and 1 gynecologist discussed 4 key domains: menses irregularity and anovulation, fertility, pregnancy outcomes, and neonatal outcomes.

RESULTS

A total of eight consensus statements were drafted. Myo-inositol (Myo) supplementation can be used to improve menses irregularities and anovulation in PCOS. Myo supplementation can be used in subfertile women with or without PCOS to reduce the dose of r-FSH for ovarian stimulation during IVF, but it should not be used to increase the clinical pregnancy rate or live birth rate. Myo supplementation can be used in the primary prevention of gestational diabetes mellitus (GDM), but should not be used to improve pregnancy outcomes in women with GDM. Myo can be preconceptionally added to folic acid in women with a previous neural tube defects (NTD)-complicated pregnancy to reduce the risk of NTDs in newborns. Myo can be used during pregnancy to reduce the risk of macrosomia and neonatal hypoglycemia in mothers at risk of GDM.

CONCLUSION

This consensus statement provides recommendations aimed at guiding healthcare practitioners in the use of inositols for the treatment or prevention of female reproductive disorders. More evidence-based data are needed to definitively establish the usefulness of Myo, the appropriate dosage, and to support the use of D-chiro-inositol (DCI) or a definitive Myo/DCI ratio.

Inositol Restores Appropriate Steroidogenesis in PCOS Ovaries Both In Vitro and In Vivo Experimental Mouse Models

Androgen excess is a key feature of several clinical phenotypes of polycystic ovary syndrome (PCOS). However, the presence of FSH receptor (FSHR) and aromatase (CYP19A1) activity responses to physiological endocrine stimuli play a critical role in the pathogenesis of PCOS. Preliminary data suggest that myo-Inositol (myo-Ins) and D-Chiro-Inositol (D-Chiro-Ins) may reactivate CYP19A1 activity. We investigated the steroidogenic pathway of Theca (TCs) and Granulosa cells (GCs) in an experimental model of murine PCOS induced in CD1 mice exposed for 10 weeks to a continuous light regimen. The effect of treatment with different combinations of myo-Ins and D-Chiro-Ins on the expression of Fshr, androgenic, and estrogenic enzymes was analyzed by real-time PCR in isolated TCs and GCs and in ovaries isolated from healthy and PCOS mice. Myo-Ins and D-Chiro-Ins, at a ratio of 40:1 at pharmacological and physiological concentrations, positively modulate the steroidogenic activity of TCs and the expression of Cyp19a1 and Fshr in GCs. Moreover, in vivo, inositols (40:1 ratio) significantly increase Cyp19a1 and Fshr. These changes in gene expression are mirrored by modifications in hormone levels in the serum of treated animals. Myo-Ins and D-Chiro-Ins in the 40:1 formula efficiently rescued PCOS features by up-regulating aromatase and FSHR levels while down-regulating androgen excesses produced by TCs.

Inositol for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis to Inform the 2023 Update of the International Evidence-based PCOS Guidelines

CONTEXT

Insulin resistance is common in women with polycystic ovary syndrome (PCOS). Inositol may have insulin sensitizing effects; however, its efficacy in the management of PCOS remains indeterminate.

OBJECTIVE

To inform the 2023 international evidence-based guidelines in PCOS, this systematic review and meta-analysis evaluated the efficacy of inositol, alone or in combination with other therapies, in the management of PCOS.

DATA SOURCES

Medline, PsycInfo, EMBASE, All EBM, and CINAHL from inception until August 2022.

STUDY SELECTION

Thirty trials (n = 2230; 1093 intervention, 1137 control), with 19 pooled in meta-analyses were included.

DATA EXTRACTION

Data were extracted for hormonal, metabolic, lipids, psychological, anthropometric, reproductive outcomes, and adverse effects by 1 reviewer, independently verified by a second.

DATA SYNTHESIS

Thirteen comparisons were assessed, with 3 in meta-analyses. Evidence suggests benefits for myo-inositol or D-chiro-inositol (DCI) for some metabolic measures and potential benefits from DCI for ovulation, but inositol may have no effect on other outcomes. Metformin may improve waist-hip ratio and hirsutism compared to inositol, but there is likely no difference for reproductive outcomes, and the evidence is very uncertain for body mass indexI. Myo-inositol likely causes fewer gastrointestinal adverse events compared with metformin; however, these are typically mild and self-limited.

CONCLUSION

The evidence supporting the use of inositol in the management of PCOS is limited and inconclusive. Clinicians and their patients should consider the uncertainty of the evidence together with individual values and preferences when engaging in shared decision-making regarding the use of inositol for PCOS.

Impact of erythropoietin and myoinositol versus metformin on insulin resistance in a rat model of polycystic ovary syndrome

This study aimed to evaluate the therapeutic role of erythropoietin (EPO) or myoinositol versus metformin (MET) in improving the reproductive functions and glucose tolerance in a rat model of polycystic ovary (PCOS). Oral letrozole (LTZ) was used for induction of PCOS in wester rats for 21 days, after that, MET, EPO and myoinositol were administered for the following 21 days. The LTZ-induced PCOS rats have lost their oestrous cyclicity and become fixed at the diestrus phase, developed insulin resistance, abnormal sex and gonadotrophin hormone serum levels, increased cystic follicles, decreased number of the growing follicles and very little or no corpora lutea on microscopic examination, which were reversed by the three drugs, MET, EPO and myoinositol. MET and myoinositol were mostly equally effective in improving the reproductive manifestations of the disease. However, EPO was most effective in decreasing the insulin level observed in this LTZ-induced model of PCOS.

The Effects of Myo-Inositol and D-Chiro-Inositol in a Ratio 40:1 on Hormonal and Metabolic Profile in Women with Polycystic Ovary Syndrome Classified as Phenotype A by the Rotterdam Criteria and EMS-Type 1 by the EGOI Criteria

SETTING

Insulin resistance (IR) and compensatory hyperinsulinemia are considered contributing factors toward polycystic ovary syndrome (PCOS).

OBJECTIVES

This study evaluates the frequency of metabolic abnormalities in PCOS patients and the effects of myo-inositol (MI) and D-chiro-inositol (DCI), in a 40:1 ratio on hormonal and metabolic parameters.

PARTICIPANTS

Thirty-four women with PCOS phenotype A (endocrine-metabolic syndrome [EMS-type 1]) between the ages of 20-40.

DESIGN

Open prospective study with phenotype A (EMS-type I, n = 34) supplemented with 2,255 mg/day of inositol (MI and DCI in a 40:1 ratio) for 3 months.

METHODS

The following were measured before and after treatment: serum levels of follicular stimulating hormone, luteinizing hormone (LH), estradiol, total and free testosterone, sex hormone-binding globulin (SHBG), free androgen index (FAI), anti-Müllerian hormone, glucose, insulin, HOMA-IR, and body mass index (BMI).

RESULTS

55.9% of the enrolled patients were overweight or obese, 50% affected by IR, 17.6% with a history of gestational diabetes mellitus, and 61.8% had familial diabetes mellitus. At the conclusion of the study, BMI (p = 0.0029), HOMA-IR (p < 0.001) significantly decreased, along with decreased numbers of patients with elevated insulin levels. The supplementation resulted in decreased total testosterone (p < 0.001), free testosterone (p < 0.001), FAI (p < 0.001), and LH (p < 0.001); increased SHBG (p < 0.001) and estradiol (p < 0.001).

LIMITATIONS

The present analysis was limited to a 12-week follow-up, which precluded a long-term evaluation of the effects of MI and DCI combination. Also, this period was insufficient to achieve and analyze clinical changes such as restoration of the menstrual cycle, restoration of reproductive function, and clinical manifestations of hyperandrogenism.

CONCLUSIONS

Supplementation improved metabolic and hormonal profile in PCOS phenotype A (EMS-type I) patients. This builds upon previous work that demonstrated that combined inositol treatment may be effective in PCOS. The study presented herein, used a reduced concentration than in prior literature; however, a significant change in hormonal and metabolic parameters was still observed.

Inositols in treating polycystic ovary syndrome and non-insulin dependent diabetes mellitus: now and the future

INTRODUCTION

This Expert Opinion covers recent updates in the use of Inositol in polycystic ovary syndrome (PCOS) and type II diabetes and gives support to researchers and clinicians.

AREAS COVERED

This article discusses the role of Myo-Inositol (MI) and D-Chiro-Inositol (DCI) in physiological function, the use of MI in PCOS, the risks of using DCI in reproductive conditions, the 40:1 combination of MI/DCI in PCOS. Furthermore, we discuss the issues of insulin resistance and how α-lactalbumin may increase the intestinal bioavailability of MI. The paper then transitions to talk about the use of inositols in diabetes, including type II diabetes, Gestational Diabetes Mellitus (GDM), and double diabetes. Literature searches were performed with the use of PubMed, Google Scholar, and Web of Science between July and October 2023.

EXPERT OPINION

Inositol therapy has grown in the clinical field of PCOS, with it demonstrating an efficacy like that of metformin. The use of α-lactalbumin has further supported the use of MI, as issues with intestinal bioavailability have been largely overcome. In contrast, the effect of inositol treatment on the different PCOS phenotypes remains an outstanding question. The use of inositols in type II diabetes requires further study despite promising analogous data from GDM.

Combined Inositols, α-Lactalbumin, Gymnema Sylvestre and Zinc Improve the Lipid Metabolic Profile of Patients with Type 2 Diabetes Mellitus: A Randomized Clinical Trial

Type 2 diabetes mellitus (T2DM) is characterized by high blood glucose levels and lipid alterations. Besides pharmacological treatment, lifestyle modifications and nutraceuticals can be used to manage glucose and lipid profiles, which is crucial for preventing, or avoiding, serious consequences associated with the condition. This randomized controlled clinical trial on 75 patients with T2DM evaluated the effects of a combination of myo-inositol and d-chiro-inositol (40:1), α-lactalbumin, Gymnema sylvestre, and zinc on glucose and lipid profile. The intention-to-treat analysis displayed no significant differences in glucose parameters between the groups; however, the study group displayed reduced levels of total cholesterol (p = 0.01) and LDL (p = 0.03) after 3 months of supplementation. A subgroup analysis involving patients who did not modify their antidiabetic therapy, after 6 months displayed improved levels of total cholesterol (p = 0.03) and LDL (p = 0.04) in the study group versus placebo, along with a greater body weight reduction (p = 0.03) after 3 months. Furthermore, within the study group, levels of HDL (p = 0.03) and triglycerides (p = 0.04) improved after 3 months. These findings support supplementation with myo-inositol and d-chiro-inositol (40:1), α-lactalbumin, Gymnema sylvestre, and zinc as an adjuvant and safe strategy to manage the lipid profiles of patients with T2DM.

Myo-Inositol and D-Chiro-Inositol as Modulators of Ovary Steroidogenesis: A Narrative Review

Myo-inositol is a natural polyol, the most abundant among the nine possible structural isomers available in living organisms. Inositol confers some distinctive traits that allow for a striking distinction between prokaryotes and eukaryotes, the basic clusters into which organisms are partitioned. Inositol cooperates in numerous biological functions where the polyol participates or by furnishing the fundamental backbone of several related derived metabolites, mostly obtained through the sequential addition of phosphate groups (inositol phosphates, phosphoinositides, and pyrophosphates). Overall myo-inositol and its phosphate metabolites display an entangled network, which is involved in the core of the biochemical processes governing critical transitions inside cells. Noticeably, experimental data have shown that myo-inositol and its most relevant epimer D-chiro-inositol are both necessary to permit a faithful transduction of insulin and of other molecular factors. This improves the complete breakdown of glucose through the citric acid cycle, especially in glucose-greedy tissues, such as the ovary. In particular, while D-chiro-inositol promotes androgen synthesis in the theca layer and down-regulates aromatase and estrogen expression in granulosa cells, myo-inositol strengthens aromatase and FSH receptor expression. Inositol effects on glucose metabolism and steroid hormone synthesis represent an intriguing area of investigation, as recent results have demonstrated that inositol-related metabolites dramatically modulate the expression of several genes. Conversely, treatments including myo-inositol and its isomers have proven to be effective in the management and symptomatic relief of a number of diseases associated with the endocrine function of the ovary, namely polycystic ovarian syndrome.

The Role of Inositols in the Hyperandrogenic Phenotypes of PCOS: A Re-Reading of Larner’s Results

Polycystic ovarian syndrome (PCOS) is the most common endocrinological disorder in women, in which, besides chronic anovulation/oligomenorrhea and ovarian cysts, hyperandrogenism plays a critical role in a large fraction of subjects. Inositol isomers—myo-Inositol and D-Chiro-Inositol—have recently been pharmacologically effective in managing many PCOS symptoms while rescuing ovarian fertility. However, some disappointing clinical results prompted the reconsideration of their specific biological functions. Surprisingly, D-Chiro-Ins stimulates androgen synthesis and decreases the ovarian estrogen pathway; on the contrary, myo-Ins activates FSH response and aromatase activity, finally mitigating ovarian hyperandrogenism. However, when the two isomers are given in association—according to the physiological ratio of 40:1—patients could benefit from myo-Ins enhanced FSH and estrogen responsiveness, while taking advantage of the insulin-sensitizing effects displayed mostly by D-Chiro-Ins. We need not postulate insulin resistance to explain PCOS pathogenesis, given that insulin hypersensitivity is likely a shared feature of PCOS ovaries. Indeed, even in the presence of physiological insulin stimulation, the PCOS ovary synthesizes D-Chiro-Ins four times more than that measured in control theca cells. The increased D-Chiro-Ins within the ovary is detrimental in preserving steroidogenic control, and this failure can easily explain why treatment strategies based upon high D-Chiro-Ins have been recognized as poorly effective. Within this perspective, two factors emerge as major determinants in PCOS: hyperandrogenism and reduced aromatase expression. Therefore, PCOS could no longer be considered a disease only due to increased androgen synthesis without considering the contemporary downregulation of aromatase and FSH receptors. Furthermore, these findings suggest that inositols can be specifically effective only for those PCOS phenotypes featured by hyperandrogenism.

Long-Lasting Therapies with High Doses of D-chiro-inositol: The Downside

Background: Recent studies reported possible concerns following long-lasting treatments with high doses of D-chiro-inositol in women. However, to date, no clinical trial has investigated or validated these concerns. We addressed this issue both retrospectively and with a prospective pilot study. Methods: For the retrospective analysis, we searched our databases for insulin-resistant women who took 1200 mg/day D-chiro-inositol for 6 months. In our prospective study, we enrolled 10 healthy women to supplement with the same therapeutic scheme. We performed statistical analyses through the Wilcoxon Signed-Rank Test. A p-value < 0.05 was considered significant. Results: Twenty women underwent 6 months of 1200 mg/day D-chiro-inositol. The treatment significantly decreased BMI, glycemia, insulinemia, HOMA-IR, serum levels of LH, total testosterone, and DHEAS. Serum estradiol rose and menstrual abnormalities occurred following the treatment. In our prospective study, we observed increases in serum levels of total testosterone and asprosin in healthy women. Conclusions: This is the first clinical evidence demonstrating that long-term treatments with high dosages of D-chiro-inositol can predispose women to hormonal and menstrual abnormalities. Moreover, the accumulation of D-chiro-inositol following such treatment regimen may lead to detrimental effects in non-reproductive tissues, as demonstrated by the increase in asprosin levels.

Dietary supplements for polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most prevalent female endocrine reproductive disorders, affecting between 4 to 18% of the women in their reproductive age. It is generally characterized by several clinical aspects, among which anovulation, inflammation and infertility. Moreover, PCOS has several health implications, including increased metabolic, reproductive, and psychological risks. Previously, metformin and to some extent thiazolidinediones were considered as drug of choice for PCOS management, but they had several side-effects, and controversial results were obtained about their efficiency, especially in non-insulin-resistant non-obese patients. Thus, alternative treatment options are now being studied for PCOS, including different natural molecules and complementary medicines (CM) for the improvement of their health, wellbeing and fertility. Recently, treatment of PCOS patients with different natural molecules, coming from nutritional supplements and herbal medicines, has attained satisfactory results with the absence of any side effects. In this review, four natural molecules, curcumin, vitamin D, inositol and CoQ10 are discussed for their therapeutic ability. These molecules proved to decrease insulin sensitivity and inflammation, to improve the restoration of ovarian function, and they could restore hormonal balance and regulate the menstrual cycle, all of which are the main features and major concerns for women suffering from PCOS.

Putative Complementary Compounds to Counteract Insulin-Resistance in PCOS Patients

Polycystic ovary syndrome (PCOS) is the most frequent endocrine-metabolic disorder among women at reproductive age. The diagnosis is based on the presence of at least two out of three criteria of the Rotterdam criteria (2003). In the last decades, the dysmetabolic aspect of insulin resistance and compensatory hyperinsulinemia have been taken into account as the additional key features in the etiopathology of PCOS, and they have been widely studied. Since PCOS is a complex and multifactorial syndrome with different clinical manifestations, it is difficult to find the gold standard treatment. Therefore, a great variety of integrative treatments have been reported to counteract insulin resistance. PCOS patients need a tailored therapeutic strategy, according to the patient’s BMI, the presence or absence of familiar predisposition to diabetes, and the patient’s desire to achieve pregnancy or not. The present review analyzes and discloses the main clinical insight of such complementary substances.

The Improvement Effect of D-Chiro-Inositol and Ecklonia cava K. in the Rat Model of Polycystic Ovarian Syndrome

Introduction: Polycystic Ovarian Syndrome (PCOS) is known to be an endocrine state that is characterized by oligomenorrhea, hyperandrogenism, and highly cystic follicles in the ovaries. The use of food ingredients and traditional medicine in Asian countries is well known, and previous studies have shown that Ecklonia cava K. [Alariaceae] (EC) is able to alleviate PCOS symptoms. D-Chiro-inositol (DCI) administration in pathologies where steroid biosynthesis is a crucial factor, i.e., PCOS, has provided satisfactory results.

Methods: Therefore, we studied the synergistic effects of the two previously known active compounds. In rats with letrozole-induced PCOS, we focused on alternative therapies using EC and/or DCI extracts to alleviate ovarian failure.

Results: As a nonsteroidal aromatase inhibitor, letrozole inhibits the conversion of testosterone to estrogen and subsequently causes PCOS. We divided 6-week-old female mice into the following six groups and evaluated them: vehicle, PCOS, PCOS + MET (metformin), PCOS + DCI, PCOS + EC, and PCOS + DCI + EC. In our study, PCOS rats treated with EC and DCI had low serum LH and T levels and low serum levels of inflammatory cytokines such as TNFα and IL-6. These treatments also appeared to regulate the production of factors that affect follicle formation and inflammation in the ovaries.

Conclusion: We concluded that EC extract and/or DCI administration influenced aromatase production and reduced LH and T stimulation, and cotreatment with EC and DCI consequently restored ovarian dysfunction or anti-inflammatory responses in rats with PCOS-like symptoms.

D-chiro-Inositol facilitates adiponectin biosynthesis and activates the AMPKα/PPARs pathway to inhibit high-fat diet-induced obesity and liver lipid deposition

D-chiro-Inositol (DCI) is a natural cyclohexanol isomer that widely exists in all living beings, which can effectively prevent glucose and lipid metabolism disorders in mammals. This study revealed the DCI elevated adiponectin levels to reduce obesity and hepatic lipid deposition in high-fat diet (HFD) fed mice. Twelve weeks of DCI supplementation (50 and 100 mg per kg body weight per day) lowered body weight and serum triglyceride, total cholesterol, insulin, and fasting glucose levels. Histopathology analysis revealed that DCI inhibited hepatic steatosis and adipocyte expansion. Remarkably, DCI significantly increased serum adiponectin levels and upgraded the expressions of adiponectin receptors (AdipoR1 and AdipoR2) in the liver. The results of western blot and qRT-PCR showed that DCI impeded the inhibitory effect of HFD on liver AMPKα and PPARs activities through activating AdipoRs and regulated downstream fatty acid metabolism. In addition, we analyzed the concentration difference of DCI in mouse liver and adipose tissue by the HRLC-MS/MS technology, indicating the preference of DCI in different tissues. Therefore, DCI relieved liver lipid deposition and hyperlipidemia potentially by promoting adiponectin synthesis in white adipose tissue and activating the AdipoR-AMPKα/PPARs pathway in the liver.

Polycystic ovarian syndrome-current pharmacotherapy and clinical implications

Polycystic ovary syndrome (PCOS), the most common endocrinopathy in women is characterized by polycystic ovaries, chronic anovulation and hyperandrogenism. The treatment in PCOS is mainly symptomatic and involves lifestyle interventions and medications such as Metformin, Oral contraceptives and Antiandrogens. However, the management of PCOS is challenging and current interventions are not able to deal with outcomes of this syndrome. This review encompasses latest pharmacotherapeutic and non-pharmacotherapeutic interventions currently in use to tackle various symptomatic contentions in PCOS. Our focus has been mainly on novel therapeutic modalities for treatment/management of PCOS, like use of newer insulin sensitizers viz., Inositols, Glucagon-like peptide-1(GLP-1) agonists, Dipeptidyl pepdidase-4 (DPP-4) inhibitors, and sodium-glucose transport protein 2 (SGLT2) inhibitors. Also, evidence suggesting the use of vitamin D, statins, and Letrozole as emerging therapies in PCOS have been summarized in this review. Additionally, novel cosmetic techniques like electrolysis, laser and use of topically applied eflornithine to tackle the most distressing feature of facial hirsutism associated with PCOS, non-pharmacological therapy like acupuncture and the role of herbal medicine in PCOS management have also been discussed.

Inositols in the ovaries: activities and potential therapeutic applications

INTRODUCTION

Myo-inositol (MI) and d-chiro-inositol (DCI) play a key role in ovarian physiology, as they are second messengers of insulin and gonadotropins. Ex-vivo and in-vitro experiments demonstrate that both isomers are deeply involved in steroid biosynthesis, and that reduced MI-to-DCI ratios are associated with pathological imbalance of sex hormones.

AREAS COVERED

This expert opinion provides an overview of the physiological distribution of MI and DCI in the ovarian tissues, and a thorough insight of their involvement into ovarian steroidogenesis. Insulin resistance and compensatory hyperinsulinemia dramatically reduce the MI-to-DCI ratio in the ovaries, leading to gynecological disorders characterized by hyperandrogenism, altered menstrual cycle and infertility.

EXPERT OPINION

Available evidence indicates that MI and DCI have very specific physiological roles and, seemingly, physiological MI-to-DCI ratios in the ovaries are crucial to maintain the correct homeostasis of steroids. Inositol treatments should be evaluated on the patients' specific conditions and needs, as long-term supplementation of high doses of DCI may cause detrimental effects on the ovarian functionality. In addition, the effects of inositol therapy on the different PCOS phenotypes should be further investigated in order to better tailor the supplementation.

Inositols: From Established Knowledge to Novel Approaches

Myo-inositol (myo-Ins) and D-chiro-inositol (D-chiro-Ins) are natural compounds involved in many biological pathways. Since the discovery of their involvement in endocrine signal transduction, myo-Ins and D-chiro-Ins supplementation has contributed to clinical approaches in ameliorating many gynecological and endocrinological diseases. Currently both myo-Ins and D-chiro-Ins are well-tolerated, effective alternative candidates to the classical insulin sensitizers, and are useful treatments in preventing and treating metabolic and reproductive disorders such as polycystic ovary syndrome (PCOS), gestational diabetes mellitus (GDM), and male fertility disturbances, like sperm abnormalities. Moreover, besides metabolic activity, myo-Ins and D-chiro-Ins deeply influence steroidogenesis, regulating the pools of androgens and estrogens, likely in opposite ways. Given the complexity of inositol-related mechanisms of action, many of their beneficial effects are still under scrutiny. Therefore, continuing research aims to discover new emerging roles and mechanisms that can allow clinicians to tailor inositol therapy and to use it in other medical areas, hitherto unexplored. The present paper outlines the established evidence on inositols and updates on recent research, namely concerning D-chiro-Ins involvement into steroidogenesis. In particular, D-chiro-Ins mediates insulin-induced testosterone biosynthesis from ovarian thecal cells and directly affects synthesis of estrogens by modulating the expression of the aromatase enzyme. Ovaries, as well as other organs and tissues, are characterized by a specific ratio of myo-Ins to D-chiro-Ins, which ensures their healthy state and proper functionality. Altered inositol ratios may account for pathological conditions, causing an imbalance in sex hormones. Such situations usually occur in association with medical conditions, such as PCOS, or as a consequence of some pharmacological treatments. Based on the physiological role of inositols and the pathological implications of altered myo-Ins to D-chiro-Ins ratios, inositol therapy may be designed with two different aims: (1) restoring the inositol physiological ratio; (2) altering the ratio in a controlled way to achieve specific effects.

An innovative approach to polycystic ovary syndrome

Myo-inositol and D-chiro-inositol are insulin sensitising agents. In the ovary, myo-inositol acts as second messenger of Follicle Stimulating Hormone (FSH). Both molecules were administered to Polycystic Ovary Syndrome (PCOS) women. The gynaecologist Vittorio Unfer was the first to give specific value to myo-inositol for the treatment of PCOS: this important innovation opened new ways of research to identify efficient therapies based on myo-inositol alone or with low doses of D-chiro-inositol. Significant successes were also gained using myo-inositol in treating male and female infertility. Unfer's researches allowed to identify "the D-Chiro-Inositol Paradox in the Ovary" and the best myo-inositol/D-chiro-inositol ratio (40:1) for the treatment of PCOS. Furthermore, his studies allowed to improve the inositol's efficacy using alpha-lactalbumin. As shown in this review, the main stages of Unfer's scientific career have been closely intertwined with important phases of the recent pharmacological research about the topic.

D-chiro-inositol, an aromatase down-modulator, increases androgens and reduces estrogens in male volunteers: a pilot study

BACKGROUND

Androgen deficiency affects men in the adulthood, causing several harmful effects at the reproductive and behavioural levels. Since aromatase is an enzyme that catalyses the conversion of androgens to estrogens, and it is responsible for an adequate balance of both sex hormones in males and females, the administration of molecules acting as down modulators may contribute to restore an abnormal enzymatic activity. A prospective pilot study was carried out to investigate the effect of D-chiro-inositol, a putative aromatase down-modulator, on serum levels of testosterone, estradiol, estrone, dehydroepiandrosterone and epiandrosterone from a group of adult male volunteers. Glucose, insulin, follicle-stimulating hormone, luteinizing hormone, inhibin B, D-chiro-inositol and myo-inositol serum levels were also measured.

RESULTS

Male volunteers were selected according to age and body mass index. Subjects with altered glycemia and/or hormonal status, due to advanced age or abnormal weight, were enrolled in the study. Each of the 10 volunteers enrolled took oral D-chiro-inositol (1 g/day) for 1 month. Serum assays of selected markers were performed at baseline (control) and after treatment. D-chiro-inositol administration was associated to reduced serum levels of estrone (- 85.0%) and estradiol (- 14.4%), and increased serum levels of testosterone (+ 23.4%) and dehydroepiandrosterone (+ 13.8%). In addition, epiandrosterone levels were higher (+39%) after treatment. On the other hand, follicle-stimulating hormone, luteinizing hormone and inhibin B did not change. A trend toward a decrease of glycemia, insulinemia and Homeostatic Model Assessment index was observed after D-chiro-inositol treatment, although differences did not reach statistical significance. D-chiro-inositol treatment did not cause any noticeable adverse effect.

CONCLUSIONS

Increased androgens and decreased estrogens seem to confirm that D-chiro-inositol acts as an aromatase down-modulator, but with a still unknown mechanism of action. This pilot study opens up new perspectives of research and therapeutic applications for D-chiro-inositol at different dosages and length of treatment. Authorization number 005/2020 released by the Local Ethics Committee of Alma Res Fertility Center, Rome.

TRIAL REGISTRATION NUMBER

NCT04615767 (registry: ClinicalTrials.gov) Date of registration: November 3, 2020.

High Doses of D-Chiro-Inositol Alone Induce a PCO-Like Syndrome and Other Alterations in Mouse Ovaries

Administration of 1000-1500 mg/day D-Chiro-Inositol (DCIns) or a combination of Myo-Inositol (MyoIns) and DCIns in their plasma molar ratio (40:1) for three or more months are among recommended treatments for metabolic syndrome and/or Polycystic Ovary Syndrome (PCOS). We previously confirmed the efficacy of this formulation (8.2 mg/day MyoIns and 0.2 mg/day DCIns for 10 days) in a mouse PCOS model, but also observed negative effects on ovarian histology and function of formulations containing 0.4-1.6 mg/day DCIns. We therefore analyzed effects of higher doses of DCIns, 5, 10 and 20 mg/day, administered to young adult female mice for 21 days, on ovarian histology, serum testosterone levels and expression of the ovarian enzyme aromatase. Five mg/day DCIns (human correspondence: 1200 mg/day) altered ovarian histology, increased serum testosterone levels and reduced the amount of aromatase of negative controls, suggesting the induction of an androgenic PCOS model. In contrast, 10-20 mg/day DCIns (human correspondence: 2400-4800 mg/day) produced ovarian lesions resembling those typical of aged mice, and reduced serum testosterone levels without affecting aromatase amounts, suggesting a failure in steroidogenic gonadal activity. Notwithstanding physiological/biochemical differences between mice and humans, the observed pictures of toxicity for ovarian histology and function recommend caution when administering DCIns to PCOS patients at high doses and/or for periods spanning several ovulatory cycles.

Natural Molecules in the Management of Polycystic Ovary Syndrome (PCOS): An Analytical Review

Polycystic ovary syndrome (PCOS) is a heterogenous disorder characterized by chronic ovulation dysfunction and hyperandrogenism. It is considered the most common endocrinological disorder, affecting up to 25% of women of reproductive age, and associated with long-term metabolic abnormalities predisposing to cardiovascular risk, such as insulin resistance (IR), dyslipidemia, endothelial dysfunction, and systemic inflammation. PCOS is also characterized by elevated serum levels of luteinizing hormone (LH), causing a condition of hyperandrogenism and a consequent altered ratio between LH and the follicle stimulating hormone (FSH). Over the years, several different approaches have been proposed to alleviate PCOS symptoms. Supplementation with natural molecules such as inositols, resveratrol, flavonoids and flavones, vitamin C, vitamin E and vitamin D, and omega-3 fatty acids may contribute to overcoming PCOS pathological features, including the presence of immature oocyte, IR, hyperandrogenism, oxidative stress and inflammation. This review provides a comprehensive overview of the current knowledge about the efficacy of natural molecule supplementation in the management of PCOS.

May myo-inositol and d-chiro-inositol (40:1) treatment be a good option on normal-weighted polycystic ovary syndrome patients without insulin resistance?

AIM

To investigate the effectiveness of myo-inositol and d-chiro-inositol (MI:DCI) (40:1) treatment in normal-weight polycystic ovary syndrome (PCOS) patients without insulin resistance.

METHODS

This retrospective case-control study included PCOS patients without insulin resistance who were diagnosed in the gynecology and obstetrics clinic of Başkent University Konya Practice and Research Hospital between January 2016 and October 2019 and received at least 6 months of MI:DCI (40:1) treatment. The patients were divided into two groups according to body mass index (BMI). Twenty-nine anovulatory patients without insulin resistance with a BMI of 18-25 were included in group 1 (normal-weight group), whereas 17 patients without insulin resistance with BMI > 25 were included in group 2 (obese/overweight group). Ovulation status of both groups was compared after MI:DCI treatment.

RESULTS

Ovulation was detected in 23 of 29 patients in the normal-weight group, whereas it was detected only in 5 of 17 patients in the obese/overweight group; this difference was statistically significant (P < 0.001) (Table 2, Figure 1). Post-treatment progesterone levels of both groups were compared and in the normal-weight PCOS group was significantly higher than the obese/overweight group (P < 0.001) (Table 2, Figure 2). In addition, spontaneous pregnancy following treatment was observed in six of the seven (85.7%) patients in the normal-weight group who wanted to conceive, whereas it was observed in only two of the six (33.3%) patients in the obese/overweight group who wanted to conceive.

CONCLUSION

Our results showed that MI:DCI (40:1) treatment may be a first-line treatment in normal-weight PCOS patients without insulin resistance.

Inositols in PCOS

(1) Background: Myoinositol (MI) and D-chiro-inositol (DCI) are involved in a number of biochemical pathways within oocytes having a role in oocyte maturation, fertilization, implantation, and post-implantation development. Both inositols have a role in insulin signaling and hormonal synthesis in the ovaries. (2) Methods: Literature search (with key words: inositols, myo-inositol, d-chiro-inositol, PCOS) was done in PubMed until Sept. 2020 and 197 articles were identified, of which 47 were of clinical trials (35 randomized controlled trials). (3) Results: Many studies have demonstrated that in patients with polycystic ovarian syndrome (PCOS) MI treatment improved ovarian function and fertility, decreased the severity of hyperandrogenism including acne and hirsutism, positively affected metabolic aspects, and modulated various hormonal parameters deeply involved in the reproductive axis function and ovulation. Thus treating with MI has become a novel method to ameliorate PCOS symptoms, improve spontaneous ovulation, or induce ovulation. The current review is focused on the effects of MI and DCI alone or in combination with other agents on the pathological features of PCOS with focus on insulin resistance and adverse metabolic outcomes. (4) Conclusions: The available clinical data suggest that MI, DCI, and their combination in physiological ratio 40:1 with or without other compound could be beneficial for improving metabolic, hormonal, and reproductive aspects of PCOS.

Altered Ovarian Inositol Ratios May Account for Pathological Steroidogenesis in PCOS

The presence of abnormal ovarian ratios of myo-inositol (MI) to D-chiro-inositol (DCI) is a recurrent feature in PCOS. Available evidence suggests that MI and DCI may modulate steroid biosynthesis, likely in an opposite manner. Specifically, MI seems to induce estrogen production, while DCI has a role in the synthesis of androgens. Elevated insulin levels, generally associated with PCOS, alter the physiological MI/DCI ratio, increasing MI-to-DCI conversion through activation of a specific epimerase enzyme. DCI directly increases testosterone biosynthesis in thecal cells and reduces its conversion to estradiol by downregulating aromatase enzyme in granulosa cells. This manuscript reviews the literature that supports the connection between altered MI/DCI ratios and pathological steroidogenesis observed in PCOS women. Furthermore, it discusses the application of inositol-based treatment protocols in managing PCOS symptoms and improving the quality of patients' life.

Effect of d-chiro-inositol and alpha-lipoic acid combination on COH outcomes in overweight/obese PCOS women

Insulin resistance (IR) plays a central role in the onset of polycystic ovary syndrome (PCOS). Insulin so insulin-sensitizing like inositols have been proposed as first line therapy. Among them d-chiro-inositol (DCI) seems to improve glucose metabolism and to increase ovulation frequency. Other studies have demonstrated that alpha-lipoic acid (ALA), with its antioxidant role, can also improve endocrine and metabolic profile of PCOS patients especially with familial diabetes. This a retrospective observational study with the aim to evaluate possible advantages of an integrative preparation combining DCI 500 mg and ALA 300 mg in overweight/obese PCOS patients with or without diabetic relatives who underwent IVF. Twenty PCOS patients who were taking the integrative preparation underwent controlled ovarian hyperstimulation in our center. The group with diabetic relatives tended to have a lower dose of gonadotropin, shorter stimulation days, higher number of MII oocytes, and higher number of fertilized oocytes. A combined regimen of DCI and ALA could be an interesting strategy in overweight PCOS patients with familial diabetes underwent ART.

New clinical targets of d-chiro-inositol: rationale and potential applications

INTRODUCTION

Inositols have a key role in ovarian physiology and the literature reports a wealth of studies about the major isomer, myo-inositol (MI). However, information about d-chiro-inositol (DCI) is still scarce, despite the ratio MI:DCI is tissue-specific and actively maintained by an insulin-dependent epimerase enzyme.

AREAS COVERED

This expert opinion provides an overview of the physiological contribution of DCI in regulating steroidogenesis. DCI indeed mediates the intracellular signaling of insulin, which induces the biosynthesis of androgens. Studies on second messengers of insulin also revealed that DCI has a specific role in modulating the activity of aromatase enzyme. Specifically, recent findings demonstrated that DCI influences the enzyme gene expression, thus reducing the conversion of androgens into estrogens.

EXPERT OPINION

Available evidence suggests that the effects of DCI administration may be similar to those of aromatase inhibitors, but without causing hypo-estrogenic states. Therefore, DCI treatments should be evaluated for either estrogen-dependent gynecological conditions or low testosterone states in male subjects.

Inositols in Polycystic Ovary Syndrome: An Overview on the Advances

This review details the physiologic roles of two insulin sensitizers, myo-inositol (MI) and d-chiro-inositol (DCI). In the human ovary, MI is a second messenger of follicle-stimulating hormone (FSH) and DCI is an aromatase inhibitor. These activities allow a treatment for polycystic ovary syndrome (PCOS) to be defined based on the combined administration of MI and DCI, where the best MI:DCI ratio is 40:1. Moreover, MI enhances the effect of metformin and clomiphene on the fertility of PCOS women seeking pregnancy. As impaired intestinal transport may lead to unsuccessful inositol treatment, we also discuss new data on the use of alpha-lactalbumin to boost inositol absorption. Overall, the physiological activities of MI and DCI dictate the dosages and timing of inositol supplementation in the treatment of PCOS.

Current treatment for polycystic ovary syndrome: focus on adolescence

Polycystic ovary syndrome (PCOS) is the most frequent endocrine disorder in women and it is associated with an increased rate of infertility. Its etiology remains largely unknown, although both genetic and environmental factors play a role. PCOS is characterized by insulin resistance, metabolic disorders and low-grade chronic inflammation. To date, the treatment of PCOS is mainly symptomatic and aimed at reducing clinical signs of hyperandrogenism (hirsutism and acne), at improving menstrual cyclicity and at favoring ovulation. Since PCOS pathophysiology is still largely unknown, the therapeutic interventions currently in place are rarely cause-specific. In such cases, the therapy is mainly directed at improving hormonal and metabolic dysregulations typical of this condition. Diet and exercise represent the main environmental factors influencing PCOS. Thus, therapeutic lifestyle changes represent the first line of intervention, which, in combination with oral contraceptives, represent the customary treatment. Insulin resistance is becoming an increasingly studied target for therapy, most evidence stemming from the time-honored metformin use. Relatively novel strategies also include the use of thiazolidinediones and GLP1-receptor agonists. In recent years, a nutraceutical approach has been added to the therapeutic toolkit targeting insulin resistance. Indeed, emerging data support inositol and alpha-lipoic acid as alternative compounds, alone or in combination with the aforementioned strategies, with favorable effects on ovulation, insulin resistance and inflammation. Nevertheless, additional studies are required in adolescents, in order to assess the effectiveness of diet supplements in preventing negative impacts of PCOS on fertility in adult age. This review focuses on the main therapeutic options for PCOS to date.

High dose of d-chiro-inositol improves oocyte quality in women with polycystic ovary syndrome undergoing ICSI: a randomized controlled trial

The aim of this study was to evaluate the effect of two doses of d-chiro-inositol (DCI) in combination with Myo-inositol (MYO) on the oocyte quality (OQ) of women with polycystic ovarian syndrome (PCOS) undergoing intracytoplasmic sperm injection (ICSI). Methods: This was a controlled, randomized, double-blind, parallel group study on 172 oocytes from 11 women. The study compared the effect of two MYO-DCI formulations given over 12 weeks on OQ. Five women received 550 mg of MYO + 300 mg of DCI daily (high DCI content group), while 6 women were given a daily dose of 550 mg of MYO with the only 27.6 mg of DCI (low DCI content group). Results: According to a multivariate analysis using linear mixed effect models, high doses of DCI have a positive influence on the quality of the cytoplasm of the oocyte (β = 1.631, χ² = 7.347, d.f. = 1, p = .00672). Zona pellucida, plasma membrane, cytoplasm, and sperm reception have also been improved with any combination of MYO/DCI by decreasing testosterone or improving insulin sensitivity, regardless of age and body mass index. Conclusion: The combination of MYO with high doses of DCI improved oocyte cytoplasm quality in women with PCOS undergoing ICSI.

Targeting Metabolic Consequences of Insulin Resistance in Polycystic Ovary Syndrome by D-chiro-inositol and Emerging Nutraceuticals: A Focused Review

Polycystic ovary syndrome (PCOS) is a complex disorder associated with ovarian dysfunction, infertility, menstrual irregularity, and hormonal impairments. Over the last decade, several studies have shown that some PCOS women have insulin resistance (InsR) and hyperinsulinemia, apart from being overweight or obese. Therefore, a crucial clinical aspect is that PCOS patients might develop glucose intolerance and type 2 diabetes. Insulin-sensitizing drugs have been used as first-line treatment to improve hyperinsulinemia in women with PCOS. Although reducing PCOS symptoms and signs, several used insulin-sensitizer drugs may induce side effects, which reduces compliance. D-chiro-inositol (DCI), which is a naturally occurring stereoisomer of inositol, has been classified as an insulin-sensitizer and seems to mitigate multiple InsR-related metabolic alterations in PCOS with a safe profile. However, according to a multi-targeted design, the supplementation with DCI can be synergistically integrated by combining other potential insulin-sensitizing drugs and/or nutraceuticals. The literature provides the initial support for using several unexplored nutraceutical interventions that may target relevant metabolic abnormalities associated with InsR in PCOS. With a need to promote interest in clinical research, this review aims to discuss the efficacy of DCI and the role of emerging nutraceuticals for managing InsR in PCOS.

Experts' opinion on inositols in treating polycystic ovary syndrome and non-insulin dependent diabetes mellitus: a further help for human reproduction and beyond

Introduction: This Experts' opinion provides an updated scientific support to gynecologists, obstetricians, endocrinologists, nutritionists, neurologists and general practitioners on the use of Inositols in the therapy of Polycystic Ovary Syndrome (PCOS) and non-insulin dependent (type 2) diabetes mellitus (NIDDM).Areas covered: This paper summarizes the physiology of Myo-Inositol (MI) and D-Chiro-Inositol (DCI), two important molecules present in human organisms, and their therapeutic role, also for treating infertility. Some deep differences between the physiological functions of MI and DCI, as well as their safety and intestinal absorption are discussed. Updates include new evidence on the efficacy exerted in PCOS by the 40:1 MI/DCI ratio, and the innovative approach based on alpha-lactalbumin to overcome the decreased therapeutic efficacy of Inositols in some patients.Expert opinion: The evidence suggests that MI, alone or with DCI in the 40:1 ratio, offers a promising treatment for PCOS and NIDDM. However, additional studies need to evaluate some still unresolved issues, such as the best MI/DCI ratio for treating NIDDM, the potential cost-effectiveness of reduced gonadotropins administration in IVF due to MI treatment, or the benefit of MI supplementation in ovulation induction with clomiphene citrate in PCOS patients.

Inositol Treatment for PCOS Should Be Science-Based and Not Arbitrary

The aim of this paper is to critically analyze the composition of many inositol-based products currently used to treat Polycystic Ovary Syndrome (PCOS). Several different combinations of myo-inositol and D-chiro-inositol, with and without additional compounds such as micro- and macroelements, vitamins, and alpha-lipoic acid, have been formulated over the years. Such therapeutic proposals do not take various features of inositol stereoisomers into consideration. As an example, it is important to know that D-chiro-inositol treatment may be beneficial when administered in low doses, yet the progressive increase of its dosage results in the loss of its advantageous effects on the reproductive performance of women and a deterioration in the quality of blastocysts created via in vitro fertilization (IVF). In addition, we have to consider that the intestinal absorption of myo-inositol is reduced by the simultaneous administration of D-chiro-inositol since the two stereoisomers compete with each other for the same transporter that has similar affinity for each of them. A decrease in myo-inositol absorption is also found when it is coadministered with inhibitors of sugar intestinal absorption and/or types of sugars such as sorbitol, maltodextrin, and sucralose. The combination of these may require higher amounts of myo-inositol in order to reach a therapeutic dosage compared to inositol administration alone, a particularly important fact when physicians strive to obtain a specific plasma level of the stereoisomer. Finally, we must point out that D-chiro-inositol was found to be an aromatase inhibitor which increases androgens and may have harmful consequences for women. Therefore, the inositol supplements used in PCOS treatment must be carefully defined. Clinical evidence has demonstrated that the 40 : 1 ratio between myo-inositol and D-chiro-inositol is the optimal combination to restore ovulation in PCOS women. Therefore, it is quite surprising to find that inositol-based treatments for PCOS seem to be randomly chosen and are often combined with useless or even counterproductive molecules, all of which can weaken myo-inositol's efficacy. Such treatments clearly lack therapeutic rationale.

Inositols' Importance in the Improvement of the Endocrine-Metabolic Profile in PCOS

Polycystic ovary syndrome (PCOS) is one of the most common causes of infertility and metabolic problems among women of reproductive age. The mechanism of PCOS is associated with concurrent alterations at the hormonal level. The diagnosis assumes the occurrence of three interrelated symptoms of varying severity, namely ovulation disorders, androgen excess, or polycystic ovarian morphology (PCOM), which all require a proper therapeutic approach. The main symptom seems to be an increased androgen concentration, which in turn may contribute to different metabolic disorders. A number of papers have demonstrated the significant role of inositol therapy in PCOS. However, there is a lack of detailed discussion about the importance of myo-inositol (MI) and d-chiro-inositol (DCI) in reference to particular symptoms. Thus, the aim of this review is to present the effectiveness of MI and DCI treatment for PCOS symptoms. Moreover, the review is focused on analyzing the use of inositols, taking into account their physiological properties, together with the mechanism of individual PCOS symptom formation.

Abnormal expression of HSP70 may contribute to PCOS pathology

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 (E₂), 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.

Comparison of the effect of two combinations of myo-inositol and D-chiro-inositol in women with polycystic ovary syndrome undergoing ICSI: a randomized controlled trial

The purpose of this study was to evaluate the effect of two doses of D-chiro-inositol (DCI) in combination with Myo-inositol (MYO) in women with PCOS undergoing ICSI. This was a multicenter controlled, randomized, double-blind parallel group study with two MYO-DCI formulations for 12 weeks. The study group (SG) was administered 550 mg of MYO + 150 mg of DCI twice daily; the control group (CG) was administered 550 mg of MYO + 13.8 mg of DCI twice daily. The participants comprised 60 women with PCOS undergoing ICSI. At baseline, no differences were found between the two groups regarding age, BMI, HOMA-IR or testosterone levels. The pregnancy and live birth rates were significantly higher in the SG than in the CG (65.5 vs. 25.9 and 55.2 vs. 14.8, respectively) [risk ratio (RR) = 0.4; 95%CI (0.2, 0.79); p = .003 and RR = 0.27; 95%CI (0.10, 0.70); p = .002 respectively]. The risk of ovarian hyperstimulation syndrome (OHSS) was lower in the SG (3.44 vs. 18.5%, p = .07). The combination of MYO-DCI at high doses of DCI improves the pregnancy rates and reduces the risk of OHSS in women with PCOS undergoing ICSI.

Recent advances in the understanding and management of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a multifaceted condition characterized by chronic anovulation and excess ovarian activity, in contrast to other causes of anovulation that involve ovarian dormancy or primary insufficiency. Recent studies indicated that PCOS is associated with low-grade chronic inflammation and that women with PCOS are at increased risk of non-alcoholic fatty liver disease. The inflammatory and metabolic derangements associated with PCOS are explained in part by the coexistence of insulin resistance and obesity but are further fueled by the androgen excess. New insights into the regulation of hormones and cytokines in muscle and fat tissue support the concept that PCOS is a systemic syndrome. The therapeutic plan should be tailored to the patient phenotype, complaints, and reproductive desire. Of note, the aromatase inhibitor letrozole seems to be more effective than the reference drug clomiphene citrate to treat infertility due to PCOS. Integral management by a multidisciplinary team may help the patients to adhere to lifestyle interventions and thereby reduce body adiposity and recover their metabolic and reproductive health.

Association between Polymorphisms of OCT1 and Metabolic Response to Metformin in Women with Polycystic Ovary Syndrome

Insulin-sensitizer treatment with metformin is widely used in polycystic ovary syndrome (PCOS). However, the treatment effectiveness shows individual differences in PCOS patients. Organic cation transporter (OCT) 1 and 2 have been reported to mediate metformin transport in the liver and kidney, respectively. In this study, we investigated the association between the polymorphisms of OCT1 and OCT2 and the treatment effectiveness of metformin in PCOS patients. The single nucleotide polymorphisms (SNPs) of OCT1 (rs683369 and rs628031) and OCT2 (rs316019) were analyzed in 87 PCOS and 113 control women. Oral glucose tolerance tests (OGTTs), which represented metformin treatment response, were conducted at the start of treatment and after six-month treatment. The results demonstrated that the SNP frequencies of OCT1 and OCT2 were not associated with PCOS pathophysiology, and that the polymorphisms of OCT1 and OCT2 were not associated with the OGTT parameters at baseline. However, PCOS patients with the G allele of OCT1 rs683369 and/or with the A allele of OCT1 rs628031 had increased insulin sensitivity compared to those with wild-type genotype after receiving metformin treatment. Moreover, the interactions of metformin*SNP were significant in both OCT1 rs683369 (p < 0.001) and rs628031 (p = 0.001) during the treatment period. Taken together, genetic polymorphisms of OCT1 contributed to different metformin treatment responses, and further study is needed to establish personalized treatment programs using a pharmacogenomic algorithm approach in PCOS patients.

The myo-inositol effect on the oocyte quality and fertilization rate among women with polycystic ovary syndrome undergoing assisted reproductive technology cycles: a randomized clinical trial

PURPOSE

The aim of the present study was to evaluate the effect of myo-Inositol administration on oocyte quality, fertilization rate and embryo quality in patients with PCOS during assisted reproductive technology (ART) cycles.

METHODS

Fifty infertile PCOS patients were randomly designated in two groups. In the study group, patients received daily doses of 4 g myo-Inositol combined with 400 mg folic acid and in the control group patients received only 400 mg folic acid from 1 month before starting the antagonist cycle until the day of ovum pick up. Oocyte and embryo qualities were assessed according to European Society of Human Reproduction and Embryology (ESHRE) guidelines. The gene expression of PGK1, RGS2 and CDC42 as a factor of oocyte quality in granulosa cells was analyzed using real-time RT-PCR. Levels of total antioxidant capacity (TAC) and reactive oxygen species (ROS) were evaluated by chemiluminescence assay in follicular fluid.

RESULTS

The percentage of metaphase II oocyte, fertilization rate and embryo quality significantly improved in the study group (p < 0.05), but the number of retrieved oocytes and follicle count were not statistically different between groups. Furthermore, the gene expression of PGK1, RGS2 and CDC42 was significantly higher in the study group (p < 0.05) but no differences were found between two groups in terms of TAC and ROS levels.

CONCLUSIONS

The present study findings suggest that myo-Inositol alters the gene expression in granulosa cells and improves oocyte and embryo quality among PCOS patients undergoing ART.

Inositols in Insulin Signaling and Glucose Metabolism

In the past decades, both the importance of inositol for human health and the complex interaction between glucose and inositol have been the subject of increasing consideration. Glucose has been shown to interfere with cellular transmembrane transport of inositol, inhibiting, among others, its intestinal absorption. Moreover, intracellular glucose is required for de novo biosynthesis of inositol through the inositol-3-phosphate synthase 1 pathway, while a few glucose-related metabolites, like sorbitol, reduce intracellular levels of inositol. Furthermore, inositol, via its major isomers myo-inositol and D-chiro-inositol, and probably some of its phosphate intermediate metabolites and correlated enzymes (like inositol hexakisphosphate kinase) participate in both insulin signaling and glucose metabolism by influencing distinct pathways. Indeed, clinical data support the beneficial effects exerted by inositol by reducing glycaemia levels and hyperinsulinemia and buffering negative effects of sustained insulin stimulation upon the adipose tissue and the endocrine system. Due to these multiple effects, myoIns has become a reliable treatment option, as opposed to hormonal stimulation, for insulin-resistant PCOS patients.