Effectiveness of myoinositol for polycystic ovary syndrome: a systematic review and meta-analysis

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.

Comparison of metformin with inositol versus metformin alone in women with polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Metformin was the first medication targeting insulin resistance in PCOS, and it has been extensively studied as a metabolic treatment option. In recent years, inositols have emerged as potential treatment options for PCOS, but confidence in the available evidence supporting their use is limited.

METHODS

We comprehensively searched PubMed, Embase, and Cochrane databases for RCTs comparing the use of combined metformin and inositol versus metformin alone in women with PCOS. A random-effects model was used to calculate the risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs). A p-value of <0.05 was deemed as statistically significant.

RESULTS

Six RCTs and 388 patients were included in the analysis, with follow-up ranging from 3 to 6 months. Combination therapy was significantly associated with improved menstrual cycle regularity (RR 1.56; 95% CI 1.01 to 2.41; p = 0.04), and lower values of modified Ferriman-Gallwey score (MD -0.97; 95% CI -1.53 to -0.40; p < 0.01) and LH/FSH ratios (MD -0.13; 95% CI -0.24 to -0.03; p = 0.01). Differences in acne (p = 0.58), body mass index (p = 0.13), fasting blood glucose (p = 0.07) and HOMA-IR (p = 0.25) were not statistically significant.

CONCLUSION

In this meta-analysis of RCTs, combination therapy was associated with cycle regularization and reduction in hirsutism and LH/FSH ratio compared to metformin monotherapy. Further studies are needed to clarify the true benefits of the use of inositol in PCOS treatment.

The Effectiveness of Myo-Inositol in Women With Polycystic Ovary Syndrome: A Prospective Clinical Study

Background Polycystic ovarian syndrome (PCOS) is a multifaceted complex endocrine disorder showing an alarming rise in women worldwide. Insulin resistance is the chief driving force in the pathogenesis of PCOS. Myo-inositol is an upcoming insulin-sensitizing agent, which is a second messenger responsible for insulin-mediated intracellular glucose transport. This study aims to evaluate the efficacy of myo-inositol and its clinical, hormonal, and metabolic profile in treating women with PCOS. Methodology A prospective clinical study was conducted over 18 months in the Department of Obstetrics and Gynecology at Sree Balaji Medical College and Hospital, Chennai, after obtaining permission from the Institutional Ethical Committee. A total of 90 women diagnosed with PCOS, according to Rotterdam's criteria, were included in the study. They received tablet myo-inositol 1 g BD for six months. Before the start of the therapy, detailed history and baseline investigations were recorded and subsequently re-assessed at the end of six months. Results Around 68% of patients restored menstrual cycle regularity. There was a statistically significant decrease in luteinizing hormone (LH) (10.31 ± 7.92 to 7.42 ± 6.25; p = 0.002), LH/follicle-stimulating hormone ratio (2.34 ± 0.34 to 1.91 ± 0.32; p = 0.000), fasting serum insulin levels (16.71 ± 13.92 to 13.18 ± 9.41; p = 0.041), and homeostatic model assessment for insulin resistance (4.52 ± 1.34 to 2.74 ± 1.28; p = 0.041). Conclusions According to our study, it was observed that myo-inositol led to a statistically significant improvement in the hormonal and metabolic profile of PCOS patients. Moreover, it is safe and has good compliance. Hence, we can justify the addition of myo-inositol to the armamentarium for PCOS management.

A Literature Review and a Proposed Classification of the Relationships between Ovulatory Infertility and Lifestyle Factors Based on the Three Groups of Ovulation Disorders Classified by WHO

Ovulatory infertility is a serious clinical problem whose direct causes are still largely unknown. In addition to pathologies that make it impossible for a couple to establish a pregnancy, there are a number of other factors that have a bearing on fertility, including lifestyle factors, and particularly diet. Although numerous studies have been performed linking such factors to ovulatory infertility, most of them lack the necessary clinical significance, instead focusing on observational data and suggesting or establishing associative relationships. This article consists of a literature review focusing on connections between lifestyle factors such as diet, physical exercise, oxidative stress, sleep, and supplementation, and ovulatory infertility. Special emphasis was given to issues such as obesity and insulin resistance and their mutual relationship with other factors linked to ovulatory infertility. In addition, based on the conclusions of the literature review, the authors have proposed a classification of relationships between ovulation disorders and lifestyle factors in ovulatory infertility within the framework of the WHO classification of ovulation disorders. Furthermore, areas that merit further research have been indicated as well as those that do not. WHO Group II disorders gained prominence in the results of the study as the number of links with lifestyle factors and ovulatory infertility found in the course of the review greatly exceeded those for Groups I and III. The data presented in the article show that the issues of proper diet and physical exercise are those that could benefit from robust clinical studies focused specifically on ovulation infertility, while studies concerning the relationship between oxidative stress, sleep, and supplementation and ovulatory infertility do not seem to be promising directions as far as clinical significance is concerned.

Effects of myo-inositol plus folic acid on ovarian morphology and oocyte quality in PCOS mouse model

Although the role of myo-inositol (MYO) in promoting the oocyte quality of PCOS patients has been documented in human studies; the cellular effects of this supplement on oocytes have not been directly examined due to ethical limitations. In the first phase of this study, MYO dosimetry was carried out simultaneously with the PCOS model development. An effective dose was obtained following the assessment of fasting insulin and testosterone levels using ELISA and ovarian morphology appraisal by histopathology. In the second phase, following the continuous administration of the effective dose of MYO and dehydroepiandrosterone (DHEA), cellular evaluation was performed. The quality of oocytes from superovulation was analyzed by examining maturity and normal morphology percentage using a stereomicroscope, intracellular reactive oxygen species (ROS) and glutathione (GSH) levels using fluorometry, and ATP count evaluation using ELISA. The results revealed that, among the four different MYO concentrations, the 0.36 mg/g dose compared with the DHEA group reduced testosterone levels and large atretic antral follicles (LAtAnF) diameter. This dose also increased the corpus luteum count and the granulosa:theca (G/T)layer thickness ratio in antral follicles. Furthermore, this dose increased mature oocytes and normal morphology percentage, ATP count, and GSH levels; however, it decreased ROS levels in mature oocytes. Our findings provide the grounds for further cellular and molecular studies on the PCOS mouse model, suggesting that the improvement in mitochondrial function and its antioxidant properties is probably one of the mechanisms by which MYO increases oocyte quality.

Neurobiology and Applications of Inositol in Psychiatry: A Narrative Review

Inositol is a natural sugar-like compound, commonly present in many plants and foods. It is involved in several biochemical pathways, most of them controlling vital cellular mechanisms, such as cell development, signaling and nuclear processes, metabolic and endocrine modulation, cell growth, signal transduction, etc. In this narrative review, we focused on the role of inositol in human brain physiology and pathology, with the aim of providing an update on both potential applications and current limits in its use in psychiatric disorders. Overall, imaging and biomolecular studies have shown the role of inositol levels in the pathogenesis of mood disorders. However, when administered as monotherapy or in addition to conventional drugs, inositol did not seem to influence clinical outcomes in both mood and psychotic disorders. Conversely, more encouraging results have emerged for the treatment of panic disorders. We concluded that, despite its multifaceted neurobiological activities and some positive findings, to date, data on the efficacy of inositol in the treatment of psychiatric disorders are still controversial, partly due to the heterogeneity of supporting studies. Therefore, systematic use of inositol in routine clinical practice cannot be recommended yet, although further basic and translational research should be encouraged.

Female infertility in the era of obesity: The clash of two pandemics or inevitable consequence?

Obesity is an epidemic that has led to a rise in the incidence of many comorbidities: among others, reduced fertility is often under-evaluated in clinical practice. The mechanisms underlying the link between reduced fertility and obesity are numerous, with insulin resistance, hyperglycaemia and the frequent coexistence of polycystic ovary syndrome being the most acknowledged. However, several other factors concur, such as gut microbiome alterations, low-grade chronic inflammation and oxidative stress. Not only do women with obesity take longer to conceive, but in vitro fertilization (IVF) is also less likely to succeed. We herein provide an updated state-of-the-art regarding the molecular bases of what we could define as dysmetabolic infertility, focusing on the clinical aspects, as well as possible treatment.

Inositol is an effective and safe treatment in polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Metformin is the gold standard insulin sensitizer, which is widely used to treat insulin resistance in polycystic ovary syndrome (PCOS). However, metformin may induce gastrointestinal side effects.

OBJECTIVE

Inositols have long been debated as a potential alternative for metformin in treating PCOS. Therefore, the present systematic review aimed to evaluate the efficacy and safety of inositols in treating PCOS.

METHODS

The present systematic search was performed in CENTRAL, MEDLINE, and Embase from the inception until October 20th, 2021. Eligible randomized controlled trials (RCTs) included women diagnosed with PCOS and compared any inositols with metformin or placebo. Our primary outcome was cycle normalization, whereas secondary outcomes were body mass index (BMI), parameters of carbohydrate metabolism and clinical and laboratory hyperandrogenism. Results are reported as risk ratios or mean differences (MDs) with 95% confidence intervals (CIs).

RESULTS

Twenty-six RCTs were identified, including data of 1691 patients (806 inositol, 311 with placebo, and 509 metformin groups). In patients treated with inositols, the risk (CI: 1.13; 2.85) of having a regular menstrual cycle was found by 1.79 higher than in the case of placebo. Moreover, the inositols showed non-inferiority compared to metformin in this outcome. In the case of BMI (MD = -0.45; CI: -0.89; -0.02), free testosterone (MD = -0,41, CI: -0.69; -0.13), total testosterone (MD = -20.39, CI: -40.12; -0.66), androstenedione (MD = -0.69, CI: -1,16; -0.22), glucose (MD = -3.14; CI: -5.75; -0.54) levels and AUC insulin (MD = -2081.05, CI: -2745.32; -1416.78) inositol treatment induced greater decrease compared to placebo. Inositol increased sex-hormone-binding globulin significantly compared to placebo (MD = 32.06, CI:1.27; 62.85).

CONCLUSION

Inositol is an effective and safe treatment in PCOS. Moreover, inositols showed non-inferiority in most outcomes compared to the gold standard treatment; metformin.

TRIAL REGISTRATION

PROSPERO registration number: CRD42021283275.

Effects of nutrition on metabolic and endocrine outcomes in women with polycystic ovary syndrome: an umbrella review of meta-analyses of randomized controlled trials

CONTEXT

Numerous meta-analyses have been conducted on the effects of nutritional interventions on various health outcomes in women with polycystic ovary syndrome (PCOS). However, the strength of the evidence and its clinical significance are unclear.

OBJECTIVE

This umbrella review aimed to summarize the effects of nutritional interventions on women with PCOS and assess the strength of the evidence.

DATA SOURCES

PubMed, Scopus, and Web of Science were searched from inception until March 17, 2021.

DATA EXTRACTION

Meta-analyses of randomized clinical trials (RCTs) that examined the impact of dietary modifications or supplementations on women with PCOS were selected. Data extraction, quality assessments of the meta-analyses, and evaluation of the strength of the evidence were conducted independently by 2 investigators and confirmed by a third.

DATA ANALYSIS

Twenty-eight RCT meta-analyses were included, reporting 40 different outcomes. Lower carbohydrate, Dietary Approaches to Stop Hypertension, or lower glycemic index/load diets in women with PCOS significantly improved some anthropometric and metabolic characteristics (with very low to low certainty). Probiotics/synbiotics reduced fasting plasma glucose, fasting insulin (FI), and homeostasis model assessment-estimated insulin resistance (HOMA-IR) (with moderate to high certainty). Curcumin supplementation decreased fasting plasma glucose, FI, and HOMA-IR (with moderate certainty). Fish oil supplementation decreased FI and HOMA-IR, and omega-3 reduced triglycerides (with moderate certainty). There were also improvements in FI after taking vitamin D or inositol supplements (with moderate certainty). Supplementation with fish oil increased adiponectin (with high certainty), and probiotics/synbiotics reduced total testosterone (with moderate certainty). In subfertile women with PCOS, inositol increased the ovulation rates (with moderate certainty).

CONCLUSION

There was no high-certainty evidence that diets alone in women with PCOS improved health or reproductive outcomes. Supplementation with vitamin D, probiotics/synbiotics, omega-3, inositol, and curcumin showed favorable effects on some metabolic outcomes. Probiotics/synbiotics possibly reduces total testosterone, and inositol stimulates ovulation in women with PCOS.

REGISTRATION

PROSPERO registration no. CRD42021251496.

Prospective Risk of Type 2 Diabetes in Normal Weight Women with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is associated with obesity and increased risk for type 2 diabetes (T2D). However, the prospective risk of T2D in normal weight women with PCOS is debated, together with the relevant prospective screening programs for T2D in normal weight women with PCOS. Aim: To review and discuss prospective risk of T2D in normal weight women with PCOS, and to give recommendations regarding prospective screening for T2D in normal weight women with PCOS. Methods: Systematic review. Results: A systematic literature search resulted in 15 published prospective studies (10 controlled studies and 5 uncontrolled studies) regarding risk of T2D in study cohorts of PCOS, where data from normal weight women with PCOS were presented separately. In controlled studies, higher risk of T2D in normal weight women with PCOS compared to controls was reported in 4/10 studies, which included one study where T2D diagnosis was based on glucose measurement, two register-based studies, and one study where diagnosis of T2D was self-reported. Six of the 10 controlled studies reported no increased risk of T2D in normal weight women with PCOS. Four of these studies based the diagnosis of T2D on biochemical measurements, which supported the risk of surveillance bias in PCOS. In uncontrolled studies, 2/5 reported a higher risk of T2D in lean women with PCOS compared to the general population. We discuss the evidence for insulin resistance and β-cell dysfunction in normal weight women with PCOS, and aggravation in the hyperandrogenic phenotype, ageing women, and women with Asian ethnicity. Impaired glucose tolerance could be an important metabolic and vascular risk marker in PCOS. Conclusions: The risk of T2D may be increased in some normal weight women with PCOS. Individual risk markers such as hyperandrogenism, age >40 years, Asian ethnicity, and weight gain should determine prospective screening programs in normal weight women with PCOS.

Efficacy of Myo-inositol on Anthropometric, Metabolic, and Endocrine Outcomes in PCOS Patients: a Meta-analysis of Randomized Controlled Trial

Polycystic ovary syndrome (PCOS) is a common cause of female infertility, affecting 5-10% of women of reproductive age. Many studies have reported improvement in insulin resistance and thereby intracellular glucose uptake after myo-inositol treatment in PCOS patients, but these studies have a small sample size, varying methodology, and outcome analysis. Therefore, we designed a present meta-analysis of randomized controlled trials to explore the effect of myo-inositol supplementation on anthropometric, metabolic, and endocrine outcomes in PCOS patients. Randomized controlled trials assessing the effectiveness of myo-inositol were identified in electronic databases like PubMed, Cochrane, Embase, MEDLINE, CINAHL, and AMED. Listed references and citations of related articles were also screened manually to identify additional studies. Research papers for which full-text copies were not available on scientific databases were procured from respective authors. Thereafter, data were extracted from included studies and analyzed using RevMan 5.3 of the Cochrane Collaboration. A total of 17 randomized controlled trials with 1083 PCOS patients were included in this meta-analysis. Among the 17 trials, 7 trials compared myo-inositol with folic acid, 8 trials compared myo-inositol with metformin, and 2 trials compared myo-inositol with oral contraceptives. No significant improvement in body mass index, waist-to-hip ratio, fasting insulin, fasting glucose, HOMA, LH, FSH, estradiol, sex hormone-binding globulin, dehydroepiandrosterone, and total testosterone levels were observed after myo-inositol treatment in PCOS patients except androstenedione and prolactin levels. Clinically significant improvement was not observed in anthropometric, metabolic, and endocrine outcomes after myo-inositol treatment in PCOS patients. However, heterogeneity between studies was high.

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.

Polycystic ovary syndrome and type 2 diabetes mellitus: A state-of-the-art review

Polycystic ovary syndrome (PCOS) often coexists with a wide spectrum of dysglycemic conditions, ranging from impaired glucose tolerance to type 2 diabetes mellitus (T2D), which occur to a greater extent compared to healthy body mass index-matched women. This concurrence of disorders is mainly attributed to common pathogenetic pathways linking the two entities, such as insulin resistance. However, due to methodological flaws in the available studies and the multifaceted nature of the syndrome, there has been substantial controversy as to the exact association between T2D and PCOS which has not yet been elucidated. The aim of this review is to present the best available evidence regarding the epidemiology of dysglycemia in PCOS, the unique pathophysiological mechanisms underlying the progression of dysglycemia, the most appropriate methods for assessing glycemic status and the risk factors for T2D development in this population, as well as T2D risk after transition to menopause. Proposals for application of a holistic approach to enable optimal management of T2D risk in PCOS are also provided. Specifically, adoption of a healthy lifestyle with adherence to improved dietary patterns, such the Mediterranean diet, avoidance of consumption of endocrine-disrupting foods and beverages, regular exercise, and the effect of certain medications, such as metformin and glucagon-like peptide 1 receptor agonists, are discussed. Furthermore, the maintenance of a healthy weight is highlighted as a key factor in achievement of a significant reduction of T2D risk in women with PCOS.

Maintaining Effective Beta Cell Function in the Face of Metabolic Syndrome-Associated Glucolipotoxicity-Nutraceutical Options

In people with metabolic syndrome, episodic exposure of pancreatic beta cells to elevated levels of both glucose and free fatty acids (FFAs)-or glucolipotoxicity-can induce a loss of glucose-stimulated insulin secretion (GSIS). This in turn can lead to a chronic state of glucolipotoxicity and a sustained loss of GSIS, ushering in type 2 diabetes. Loss of GSIS reflects a decline in beta cell glucokinase (GK) expression associated with decreased nuclear levels of the pancreatic and duodenal homeobox 1 (PDX1) factor that drives its transcription, along with that of Glut2 and insulin. Glucolipotoxicity-induced production of reactive oxygen species (ROS), stemming from both mitochondria and the NOX2 isoform of NADPH oxidase, drives an increase in c-Jun N-terminal kinase (JNK) activity that promotes nuclear export of PDX1, and impairs autocrine insulin signaling; the latter effect decreases PDX1 expression at the transcriptional level and up-regulates beta cell apoptosis. Conversely, the incretin hormone glucagon-like peptide-1 (GLP-1) promotes nuclear import of PDX1 via cAMP signaling. Nutraceuticals that quell an increase in beta cell ROS production, that amplify or mimic autocrine insulin signaling, or that boost GLP-1 production, should help to maintain GSIS and suppress beta cell apoptosis in the face of glucolipotoxicity, postponing or preventing onset of type 2 diabetes. Nutraceuticals with potential in this regard include the following: phycocyanobilin-an inhibitor of NOX2; agents promoting mitophagy and mitochondrial biogenesis, such as ferulic acid, lipoic acid, melatonin, berberine, and astaxanthin; myo-inositol and high-dose biotin, which promote phosphatidylinositol 3-kinase (PI3K)/Akt activation; and prebiotics/probiotics capable of boosting GLP-1 secretion. Complex supplements or functional foods providing a selection of these agents might be useful for diabetes prevention.

The effectiveness of coenzyme Q10, vitamin E, inositols, and vitamin D in improving the endocrine and metabolic profiles in women with polycystic ovary syndrome: a network Meta-analysis

OBJECTIVE

This research evaluated the efficacy of oral nutritional agents including CoQ10, vitamin E, inositols and vitamin D on androgen-associated hormones, glycolipid metabolism and body weight in women with PCOS.

METHOD

A multi-database search was performed from inception to December 2020. Using multi-variate random effects method, a NMA was conducted by synthesizing data pooled from RCTs. It was registered with PROSPERO (registration number CRD42021230292).

RESULTS

Twenty-three RCTs and 1291 participants were included. Based on NMA, CoQ10, vitamin E, CoQ10 combined with vitamin E, and inositols were successful in decreasing TT as compared with PA; vitamin E was superior to other agents. Vitamin E and inositols were successful in increasing SHBG levels; inositols were stronger than vitamin E. CoQ10 alone or combined with vitamin E, and inositols were successful in decreasing HOMA-IR. Inositols had the best results among included nutraceuticals to ameliorate HOMA-IR, FBG, FINS, TG, TC, and LDL-C and correlated to improvements in BMI. There was no significant difference between the CoQ10 or vitamin E group and the PA group in ameliorating lipid metabolism, and vitamin D had no positive effects in ameliorating hyperandrogenism, BMI, glycolipid metabolism profiles compared with PA.

CONCLUSION

For women with PCOS, inositols supplementation have some certain advantages in increasing SHBG and improving glycolipid metabolism when compared with nutraceuticals like CoQ10, vitamin E, vitamin D. Besides, vitamin E may be a better option in reducing TT and increasing SHBG. CoQ10 alone or combined with vitamin E can be helpful in decreasing HOMA-IR as well.

Efficacy of myo-inositol and d-chiro-inositol combination on menstrual cycle regulation and improving insulin resistance in young women with polycystic ovary syndrome: A randomized open-label study

OBJECTIVE

To compare the effect of myo-inositol and d-chiro-inositol in combination (MI + DCI) with combined hormonal contraceptive (CHC) on menstrual cycle regulation in young Indian women with polycystic ovary syndrome (PCOS).

METHODS

Seventy young women with PCOS aged 15-24 years with delayed cycles were randomized into two groups and were treated for 6 months with MI + DCI (550 + 150 mg, 3.6:1 ratio) twice a day and CHC (ethinyl estradiol 20 µg + drospirenone 3 mg) once a day.

RESULTS

Spontaneous menses resumed in 28 (84.85%) young women on MI + DCI, compared with withdrawal bleeding in 34 (100%) on CHC. The mean cycle length reduced with both MI + DCI (124.54 ± 8.08 to 57.75 ± 3.00 days, P < 0.001) and CHC (105.88 ± 7.96 to 30.53 ± 2.95 days, P < 0.001). Regular menstrual cycles were established in 9 (27.27%) young women with MI + DCI (P = 0.001) and 30 (88.23%) with CHC (P < 0.001). Three months after stopping the treatment, 24 young women (85.71%) on MI + DCI and 25 (73.53%) on CHC continued to have spontaneous cycles. Anti-Müllerian hormone decreased with both the drugs (P = 0.001), whereas luteinizing hormone (P = 0.001) and testosterone (P = 0.04) decreased with CHC and homeostatic model assessment of insulin resistance (P < 0.001) with MI + DCI.

CONCLUSION

Myo-inositol and d-chiro-inositol in combination (3.6:1 ratio) are effective in regularizing menstrual cycles and improving insulin resistance.

TRIAL REGISTRATION

Clinical Trials Registry of India (CTRI/2018/03/012643). http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=20969&EncHid=&userName=myo-inositol.

The role of alpha lipoic acid in female and male infertility: a systematic review

OBJECTIVE

Infertility is an increasingly frequent health condition, which may depend on female or male factors. Oxidative stress (OS), resulting from a disrupted balance between reactive oxygen species (ROS) and protective antioxidants, affects the reproductive lifespan of men and women. In this review, we examine if alpha lipoic acid (ALA), among the oral supplements currently in use, has an evidence-based beneficial role in the context of female and male infertility.

METHODS

We performed a search from English literature using PubMed database with the following keywords: 'female infertility', 'male infertility', 'semen', 'sperm', 'sub-fertile man', 'alpha-lipoic acid', ' alpha lipoic acid', 'lipoid acid', 'endometriosis', 'chronic pelvic pain', 'follicular fluid' and 'oocytes'. We included clinical trials, multicentric studies and reviews. The total number of references found after automatically and manually excluding duplicates was 180. After primary and secondary screening, 28 articles were selected.

RESULTS

The available literature demonstrates the positive effects of ALA in multiple processes from oocyte maturation (0.87 ± 0.9% of oocyte in MII vs 0.81 ± 3.9%; p < .05) to fertilization, embryo development (57.7% vs 75.7% grade 1 embryo; p < .05) and reproductive outcomes. Its regular administration both in sub-fertile women and men shows to reduce pelvic pain in endometriosis (p < .05), regularize menstrual flow and metabolic disorders (p < .01) and improve sperm quality (p < .001).

CONCLUSIONS

ALA represents a promising new molecule in the field of couple infertility. More clinical studies are needed in order to enhance its use in clinical practice.

Impact of myoinositol with metformin and myoinositol alone in infertile PCOS women undergoing ovulation induction cycles - randomized controlled trial

PURPOSE

To evaluate the benefits of myoinositol plus metformin versus myoinositol alone in infertile polycystic ovarian syndrome (PCOS) women undergoing ovulation induction cycles.

MATERIALS AND METHODS

Total 116 infertile PCOS women were randomized: Group I (n = 57): metformin (1500 mg) plus myoinositol (4 g) per day; Group II (n=59): myoinositol 4 g per day. Subjects were advised to try for spontaneous conception. Those who did not conceive after three months were given three cycles of ovulation induction. Primary outcome was clinical pregnancy rate after 6 months. Secondary outcomes were improvement in metabolic and endocrine parameters, ongoing pregnancy, abortion and multiple pregnancy rate.

RESULTS

Baseline demographic, metabolic and hormonal parameters were comparable in two groups. After 3 months of therapy, both study groups had comparable improvement in metabolic and hormonal parameters. After 6 months, clinical pregnancy rate was 42.0% in Group I and 45.5% Group II respectively (RR 0.92(95% CI:0.60-1.43) (p > .05). Side-effects (mainly gastrointestinal) were significantly higher in Group I than group II.

CONCLUSIONS

Myoinositol (4 g) might be used alone as an insulin sensitizer to improve metabolic, hormonal and reproductive outcome in infertile PCOS women. Further studies with large numbers are warranted to confirm the role of myoinostiol as a sole insulin sensitizer.

Improvement of Insulin Sensitivity Increases Pregnancy Rate in Infertile PCOS Women: A Systemic Review

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common cause of infertility in reproductive-age women. Insulin increases steroidogenesis, deranges granulosa cell differentiation, and affects follicle growth. However, results from randomized control trials (RCTs) were heterogeneous, and little strong evidence associated actual achievement of insulin sensitivity (IS) improvement with reproductive outcomes.

OBJECTIVES

To identify evidence of the reproductive benefit of IS improvement in infertile PCOS women by analyzing eligible RCTs.

SEARCH STRATEGY

Different search strategies with unlimited keywords, including treatment, therapy, intervention, polycystic ovary syndrome/PCOS, insulin resistance, pregnancy, conceive, live birth, and randomized controlled trials/RCT were used in databases including Pubmed, Embase, and Web of Science to November 20th, 2021.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted study details and assessed study quality.

MAIN RESULTS

Ten RCTs that covered different races and met the inclusion criteria were included for analysis and discussion. Clinical pregnancy rate was increased in infertile PCOS women when they had significant improvement of IS after treatment regardless of the various interventions (non-surgical). The benefits of IS improvement appeared superior in PCOS women without severe obesity. The effect of IS improvement on pregnancy rate was independent of the change of BMI.

CONCLUSIONS

Nonsurgical therapeutic strategies that promote superior IS improvement may aid infertile PCOS women to increase their possibility of successful pregnancy regardless of the various interventions. The improvement of IS might be more important than the reduction of BMI in the improvement of pregnancy rate in infertile PCOS women.

Tailoring treatment for PCOS phenotypes

Introduction: Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies in reproductive-aged women. Hyperandrogenism, polycystic ovaries, chronic anovulation, and metabolic aberrations are its common features. The treatment approach focuses on the main aberrations, which characterize the different phenotypes. Areas covered: Management strategies targeting the metabolic phenotype include lifestyle modifications for weight loss and improvement of dietary habits, as well as medication, such as insulin-sensitizers. The treatment of hyperandrogenic phenotype includes cosmetic procedures and the combined oral contraceptives with or without antiandrogens. The therapeutic approach to reproductive phenotype includes diet and lifestyle modifications, clomiphene citrate, and aromatase inhibitors. Alternative treatments include dietary supplements, herbs, resveratrol, myo-inositol, and acupuncture. Expert opinion: New studies have shown that higher anti-Müllerian hormone levels, gut microbiome composition, and plasma metabolomics are new parameters that are related to the most severe phenotypes. The clinical phenotypes can change over the lifespan with weight gain and can coexist in the same individual. Individualized treatment remains the main approach but grouping the phenotypes and following therapeutic recommendations may prove to be also clinically appropriate.

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.

Safety and efficacy of supplements in pregnancy

Pregnancy is a time where expectant mothers often focus on their diet to improve their own health and to preserve the future health of their children. There is much conflicting information in the public domain about the safety and/or efficacy of nutritional supplements during pregnancy. Despite this, the market for supplements is growing. This review discusses the roles of critical nutrients in pregnancy and the available evidence on the use of supplements to reduce risks and improve maternal and fetal outcomes. Recommendations are made for pregnant women, taking into account safety data and tolerable upper intakes set for pregnant women. It is important for dieticians, nutritionists, physicians, and other healthcare providers to be able to offer accurate and evidence-based advice on supplement use in pregnancy. Routine supplementation may not be necessary for all, but individuals at risk are identified.

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.

The impact of myo-inositol supplementation on sleep quality in pregnant women: a randomized, double-blind, placebo-controlled study

BACKGROUND

Myo-inositol, a glial marker which plays a critical role in some brain regions, can supposedly affect sleep processes. The purpose of randomized controlled trial was to evaluate the impact of myo-inositol supplementation on sleep quality of pregnant women.

METHODS

The study enrolled 60 women with low risk singleton pregnancies, with a gestational age of at least 14 weeks, in Iran. The participants were block randomized to receive myo-inositol supplementation powder containing 2000 mg of myo-inositol and 200 μg of folic acid or placebo (400 μg of folic acid) for 10 weeks from the gestational age of 14-24. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI). The primary outcome was the change in sleep quality from the first trimester to the second trimester (24-28 weeks). The ANCOVA with adjusted covariate variables in the first trimester was conducted to estimate the sleep quality between the two groups.

RESULTS

The results of ANCOVA boot strapped showed that the mean difference of the total sleep quality score between the two groups was -1.537; 95% CI: -3.050 to -0.024, p = .047) in the second trimester at immediately post-intervention. Also, there were significant differences between the two groups in terms of subjective sleep quality (MD: -0.427; 95% CI: -0.725 to -0.128, p = .006, sleep duration (MD: -0.670; 95% CI: -1.240 to -0.101; p = .022) and habitual sleep efficiency (MD: -0.561; 95% CI: -1.038 to -0.085, p = .022).

CONCLUSION

The research confirmed that myo-inositol supplementation can improve global sleep quality, subjective sleep quality, and sleep duration during pregnancy. Therefore, these findings applied to minimize the rate of poor sleep quality in pregnant women.

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.

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.

Decreased Insulin Resistance by Myo-Inositol Is Associated with Suppressed Interleukin 6/Phospho-STAT3 Signaling in a Rat Polycystic Ovary Syndrome Model

Myo-inositol supplementation may reduce insulin resistance (IR) with few serious side effects in patients with polycystic ovary syndrome (PCOS). To explore the mechanism of this action in an animal model, a PCOS-IR rat model was generated. Enzyme-linked immunosorbent assay was used to assess changes in ovulation function during treatment with a myo-inositol supplement, and Western blotting, real-time polymerase chain reaction, and immunohistochemistry were performed to investigate the underlying molecular mechanisms. The results showed that the myo-inositol supplement decreased the homeostatic model assessment of insulin resistance (HOMA-IR) index and significantly decreased the serum levels of luteinizing hormone (LH), LH/follicle-stimulating hormone ratio, and testosterone, while increasing the serum level of estradiol. Upregulation of interleukin 6 (IL-6), phospho-STAT3 (p-STAT3), Mir-21, and Mir-155 and significant downregulation of PPAR-γ and GLUT4 were detected in the untreated PCOS-IR rat model. However, downregulation of IL-6, p-STAT3, miR-21, and miR-155 and significant upregulation of PPAR-γ and GLUT4 were detected with myo-inositol supplementation. Thus, myo-inositol supplementation may reduce Mir-21 and Mir-155 levels by downregulating IL-6 and p-STAT3 and, subsequently, reverse the expression of PPAR-γ and GLUT4, leading to a decreased HOMA-IR index. In conclusion, the identification of an IL-6/p-STAT3/Mir-155/Mir-21/PPAR-γ/GLUT4 system in the PCOS-IR rat model provides insight into the pathogenesis of PCOS and may indicate a possible therapeutic strategy. Amelioration of the basal serum glucose levels and of the HOMA/HOMA-IR index may be achieved by the reversal of the expression of PPAR-γ and GLUT4 through the downregulation of IL-6, p-STAT3, miR-21, and miR-155 with myo-inositol supplementation.

Clinical and Metabolic Effects of Alpha-Lipoic Acid Associated with Two Different Doses of Myo-Inositol in Women with Polycystic Ovary Syndrome

The aim of this retrospective study was to evaluate the effects of a treatment with α-lipoic acid (ALA) associated with two different doses of myo-inositol (MI) on clinical and metabolic features of women with polycystic ovary syndrome (PCOS). Eighty-eight women received the treatment, and 71 among them had complete clinical charts and were considered eligible for this study. All women were treated with 800 mg of ALA per day: 43 patients received 2000 mg of MI and 28 received 1000 mg of MI per day. Menstrual cyclicity, BMI, FSH, LH, estradiol, testosterone, androstenedione, fasting insulin, HOMA-IR, and insulin response to a 2 h OGTT were evaluated before and after 6 months of treatment. The presence of diabetic relatives (DRs) was investigated. Cycle regularity was improved in 71.2% of women. The improvement of menstrual cyclicity occurred regardless of the state of IR and the presence of DRs of the patients. Women with IR mainly showed a significant improvement of metabolic parameters, while those without IR had significant changes of reproductive hormones. Patients with DRs did not show significant changes after the treatment. 85.7% of women taking 2000 mg of MI reported a higher improvement of menstrual regularity than those taking 1000 mg of MI (50%; p < 0.01). In conclusion, ALA + MI positively affects the menstrual regularity of women with PCOS, regardless of their metabolic phenotype, with a more evident effect with a higher dose of MI. This effect seems to be insulin independent. The presence of IR seems to be a predictor of responsivity to the treatment in terms of an improvement of the metabolic profile.

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.

From Prediabetes to Type 2 Diabetes Mellitus in Women with Polycystic Ovary Syndrome: Lifestyle and Pharmacological Management

AIMS

Despite the very clear association between polycystic ovary syndrome (PCOS) and dysglycemia, few studies have explored the continuum of glycemic alterations leading from minor glucose abnormalities to overt diabetes. The purpose of this review is to trace the natural history of glycemic alteration in women with PCOS.

METHODS

We performed a literature review without time limit until August 2019. Inclusion criteria were studies addressing the association between impaired glucose tolerance or impaired fasting glucose or type 2 diabetes (T2D) and PCOS with at least an English abstract. The exclusion criteria were no PCOS or impaired glucose tolerance or impaired fasting glucose or T2D as outcome. The outcomes of interest were the onset of impaired glucose tolerance, impaired fasting glucose, T2D, and the progression from impaired glucose tolerance or impaired fasting glucose to T2D.

RESULTS

Healthy diet and physical activity are the first-line therapy for PCOS. Treatment with metformin was associated with significant lower 2-hour postload glucose levels and with reduction in fasting glucose when compared to placebo. Thiazolidinediones were more effective in reducing fasting glucose levels compared to placebo. Metformin and pioglitazone treatments showed similar effects on fasting glucose levels. The sodium-glucose cotransporter-2 inhibitor empagliflozin did not show differences in metabolic parameters when compared to metformin. The combination therapy with metformin plus the glucagon-like peptide-1 receptor agonist liraglutide was associated with significant improvements in basal and postload glucose levels compared with only liraglutide. Likewise, a combination therapy with the dipeptidyl peptidase-4 inhibitor saxagliptin and metformin demonstrated superiority versus metformin in fasting glucose and oral glucose tolerance test normalization. Myo-inositol supplementation was associated with lower insulin levels, glucose levels, and insulin resistance when compared with placebo, metformin, or estrogen treatments.

CONCLUSIONS

The use of insulin-sensitizing agents, such as metformin and inositols, along with lifestyle interventions may improve the metabolic profile in PCOS women.

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.

Current Resources for Evidence-Based Practice, March 2019

A review of new resources to support the provision of evidence-based care for women and infants.