An update on the use of inositols in preventing gestational diabetes mellitus (GDM) and neural tube defects (NTDs)

Protective Effect of myo-Inositol Against Decitabine-Induced Neural Tube Defects in Embryonic Zebrafish

Neural tube defects (NTDs) are severe congenital anomalies affecting 1-2 infants per 1000 births, and are influenced by genetic and environmental factors, with DNA hypomethylation and methylation cycle suppression being key causes. In our earlier investigation, decitabine (DCT) caused multiple NTDs in embryonic zebrafish, supporting this hypothesis. Recent research has emphasized the importance of myo-inositol (MI) in embryonic development and its efficacy in reducing the risk of neural tube defects, even in cases resistant to folate. We aimed to examine the effect of MI on DCT-induced NTDs in an embryonic zebrafish model. The embryos were exposed to 1 mM DCT alone, 50 µM MI with 1 mM DCT, 100 µM MI with 1 mM DCT, and a control group for comparison. The development, hatching, mortality rates, neural tube malformations, and neural tube patterning of developing embryos were monitored and recorded. Exposure to MI significantly reduced the incidence of NTDs in developing embryos. At concentrations of 50 µM and 100 µM, MI provided 35% and 30% protection against DCT-induced neural tube malformation, respectively. Multiple NTDs were significantly reduced in the MI groups, with 1 mM DCT causing 95% defects, 50 µM MI with 1 mM DCT causing 50%, and 100 µM MI with 1 mM DCT causing 55% defects. The DCT-induced hatching delay was also reversed by MI treatment. Alizarin red staining and histopathological observations supported these observations. In the context of neural tube development, the protective effects of MI against DCT-induced NTDs could be attributed to its potential role in epigenetic regulation, which may influence genetic expression.

Medical nutrition therapy in physiological pregnancy and in pregnancy complicated by obesity and/or diabetes: SID-AMD recommendations

Proper nutrition is essential during pregnancy to ensure an adequate supply of nutrients to the foetus and adequate maternal weight gain. In pregnancy complicated by diabetes (both gestational and pre-gestational), diet in terms of both the intake and quality of carbohydrates is an essential factor in glycaemic control. Maternal BMI at conception defines the correct weight increase during gestation in order to reduce maternal-foetal complications related to hypo- or hyper-nutrition. The recommendations presented here, which are based on national and international guidelines and the most recently published data on nutrition in physiological pregnancy and pregnancy complicated by hyperglycaemia and/or obesity, are designed to help healthcare professionals prescribe suitable eating patterns to safeguard the health of the mother and the foetus.

Inpp5e Regulated the Cilium-Related Genes Contributing to the Neural Tube Defects Under 5-Fluorouracil Exposure

Primary cilia are crucial for neurogenesis, and cilium-related genes are involved in the closure of neural tubes. Inositol polyphosphate-5-phosphatase (Inpp5e) was enriched in primary cilia and closely related to the occurrence of neural tube defects (NTDs). However, the role of Inpp5e in the development of NTDs is not well-known. To investigate whether Inpp5e gene is associated with the neural tube closure, we established a mouse model of NTDs by 5-fluorouracil (5-FU) exposure at gestational day 7.5 (GD7.5). The Inpp5e knockdown (Inpp5e-/-) mouse embryonic stem cells (mESCs) were produced by CRISPR/Cas9 system. The expressions of Inpp5e and other cilium-related genes including intraflagellar transport 80 (Ift80), McKusick-Kaufman syndrome (Mkks), and Kirsten rat sarcoma viral oncogene homolog (Kras) were determined, utilizing quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), western blot, PCR array, and immunofluorescence staining. The result showed that the incidence of NTDs was 37.10% (23 NTDs/62 total embryos) and significantly higher than that in the control group (P < 0.001). The neuroepithelial cells of neural tubes were obviously disarranged in NTD embryos. The mRNA and protein levels of Inpp5e, Ift80, Mkks, and Kras were significantly decreased in NTD embryonic brain tissues, compared to the control (P < 0.05). Knockdown of the Inpp5e (Inpp5e-/-) reduced the expressions of Ift80, Mkks, and Kras in mESCs. Furthermore, the levels of α-tubulin were significantly reduced in NTD embryonic neural tissue and Inpp5e-/- mESCs. These results suggested that maternal 5-FU exposure inhibited the expression of Inpp5e, which resulted in the downregulation of cilium-related genes (Ift80, Mkks, and Kras), leading to the impairment of primary cilium development, and ultimately disrupted the neural tube closure.

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 supplementation for the prevention and treatment of gestational diabetes mellitus: a meta-analysis of randomized controlled trials

BACKGROUND

Inositol is a potential new therapeutic agent for gestational diabetes mellitus (GDM), but its effectiveness is still controversial. The aim of the report was to evaluate the effectiveness of inositol to preventing or reducing the severity of GDM.

METHODS

We searched PubMed, EmBase, Web of science, Cochrane library databases, Clinicaltrials.gov, and International Clinical Trials Registry Platform for randomized controlled trials (RCTs) assessing the effectiveness of inositol supplementation to prevent and treat GDM. This meta-analysis was performed using the random-effects model.

RESULTS

A total of 7 RCTs (1319 pregnant women at high risk of GDM) were included in the meta-analysis. The meta-analysis found that inositol supplementation resulted in a significantly lower incidence of GDM in the inositol versus the control group (odds ratio [OR] 0.40; 95% confidence interval [CI] 0.24-0.67; P = 0.0005). The inositol group had improved fasting glucose oral glucose tolerance test (FG OGTT; mean difference [MD] = - 3.20; 95% CI - 4.45 to - 1.95; P < 0.00001), 1-h OGTT (MD = - 7.24; 95% CI - 12.23 to - 2.25; P = 0.004), and 2-h OGTT (MD = - 7.15; 95% CI - 12.86 to - 1.44; P = 0.01) results. Inositol also reduced the risk of pregnancy-induced hypertension (OR 0.37; 95% CI 0.18-0.75; P = 0.006) and preterm birth (OR 0.35; 95% CI 0.18-0.69; P = 0.003). A meta-analysis of 4 RCTs including 320 GDM patients showed that the patients' insulin resistance (P < 0.05) and neonatal hypoglycemia risk (OR 0.10, 95% CI 0.01-0.88; P = 0.04) were lower in the inositol than in the control group.

CONCLUSIONS

Inositol supplementation during pregnancy has the potential to prevent GDM, improve glycemic control, and reduce preterm birth rates.

A Markov-model simulation of IVF programs for PCOS patients indicates that coupling myo-Inositol with rFSH is cost-effective for the Italian Health System

Accumulating evidence suggests that oral supplementation with myo-Inositol (myo-Ins) is able to reduce the amount of gonadotropins and days of controlled ovarian hyperstimulation (COS) necessary to achieve adequate oocyte maturation in assisted reproduction technology (ART) protocols, particularly in women affected by polycystic ovary syndrome (PCOS). We used computational calculations based on simulation modellings. We simulated in vitro fertilization (IVF) procedures-with or without intracytoplasmic sperm injection (ICSI)-with 100,000 virtual patients, accounting for all the stages of the entire IVF procedure. A Monte Carlo technique was used to account for data uncertainty and to generate the outcome distribution at each stage. We considered virtual patients with PCOS undergoing IVF cycles to achieve pregnancy. Computational data were retrieved from clinical experience and published data. We investigated three parameters related to ART protocols: cost of single procedure; efficacy to achieve ongoing pregnancy at 12 gestational weeks; overall cost per single pregnancy. The administration of oral myo-Ins during COH protocols, compared to the standard COH with recombinant Follicle Stimulating Hormone (rFSH) only, may be considered a potential strategy to reduce costs of ART for the Italian Health System.

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.

BMP/Smad Pathway Is Involved in Lithium Carbonate-Induced Neural-Tube Defects in Mice and Neural Stem Cells

Neural-tube defects (NTDs) are one type of the most serious birth defects. Studies have shown that inositol deficiency is closely related to the occurrence of NTDs. Bone morphogenetic protein (BMP)-mediated Smad signaling pathways have been implicated in neurogenesis and neural-tube closure. However, the role of the BMP/Smad pathway in inositol-deficiency-induced NTDs remains unclear. Inositol-deficiency models in C57 mice and mouse neural stem cells (mNSCs) were induced with Li₂CO₃ treatment or inositol withdrawal. The role of the BMP/Smad pathway in the regulation of cell proliferation and the development of NTDs was determined utilizing qRT-PCR, HE staining, Western blot, immunostaining, MTT assay, EdU staining, and flow cytometry. The intraperitoneal injection of Li₂CO₃ at Embryonic Day 7.5 induced the occurrence of NTDs. The mRNA levels of Bmp2, Bmp4, Smad1, Smad5, Smad8 and Runx2, the phosphorylation of Smad1/5/8, and the nuclear translocation of Runx2 were significantly increased in NTD embryonic brain tissues and mNSCs exposed to Li₂CO₃ or an inositol-free medium, which were suppressed by BMP receptor selective inhibitor LDN-193189. The Li₂CO₃-induced phosphorylation of Smad1/5/8 was inhibited by inositol supplementation. Cell proliferation was significantly promoted by Li₂CO₃ exposure or the absence of inositol in mNSCs, which was reversed by LDN-193189. These results suggest that the activation of the BMP/Smad signaling pathway might play an important role in the development of NTDs induced by maternal Li₂CO₃ exposure via inositol deficiency.

Efficacy of microsurgery for congenital neural tube defects in newborns

OBJECTIVE

The purpose of this study was to investigate the clinical value of microsurgery in the treatment of congenital neural tube defect (CNTD) in newborns.

METHODS

Eighty-five CNTD newborns withlipomyelomeningocele admitted to our hospital from March 2016 to December 2018 were retrospectively selected as study subjects. They were divided into a study group (SG, 43 cases, that received meningocele repair combined with tethered cord release within 6 h to 30 d after birth) and the control group (CG, 42 cases, that received meningocele repair combined with tethered cord release past 30 d after birth) according to the treatment regimen. Newborns in both groups were evaluated for short-term and long-term outcome of the surgery and the degree of postoperative untethering, and both groups were followed up dynamically to record changes in gross motor function and quality of life and assess risk factors.

RESULTS

In terms of short-term outcomes, the total effective rate was 93.02% in SG and 85.71% in CG (P > 0.05); in terms of the long-term outcomes, the total effective rate was 88.37% in SG and 69.05% in CG (P < 0.05). The postoperative release of the newborns was evaluated according to the Kirollos grading system, which showed that SG had 40 (93.02%) cases of grade 1 untethering, 3 (6.98%) cases of grade 2 untethering, and 0 case of grade 3 untethering, and CG had 30 (71.43%) cases of grade 1 untethering, and 12 (28.57%) cases of grade 2 untethering. At 6 months postoperatively, there were no significant differences in gross motor function and quality of life scores between the two groups (P > 0.05), but at 1 year, 3 years and 4 years postoperatively, the gross motor function and quality of life scores of newborns in the SG were significantly higher than those in the CG (P < 0.05). Multivariate logistic regression analysis showed that age > 1 month was an independent risk factor for surgical outcome (P < 0.05).

CONCLUSION

Microsurgery has better short-term and long-term outcomes for newborns with CNTD, and the newborns showed an improvement in the long-term postoperative motor function and quality of life.

Inositol Nutritional Supplementation for the Prevention of Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This study was aimed at assessing the efficacy and safety of inositol nutritional supplementation during pregnancy for the prevention of GDM. PubMed, Embase, MEDLINE, and Cochrane library were systematically searched for randomized controlled trails (RCTs) in this field until May 2022. Primary outcomes were the incidence for GDM and plasma glucose levels by oral glucose tolerance test (OGTT). Pooled results were expressed as relative risk (RR) or mean difference (MD) with a 95% confidence interval (95% CI). Seven RCTs with 1321 participants were included in this study. Compared with the control group, 4 g myo-inositol (MI) supplementation per day significantly decreased the incidence of GDM (RR = 0.30, 95% CI (0.18, 0.49), p < 0.00001). It significantly decreased the plasma glucose levels of OGTT regarding fasting-glucose OGTT (MD = −4.20, 95% CI (−5.87, −2.54), p < 0.00001), 1-h OGTT (MD = −8.75, 95% CI (−12.42, −5.08), p < 0.00001), and 2-h OGTT (MD = −8.59, 95% CI (−11.81, −5.83), p < 0.00001). It also decreased the need of insulin treatment, and reduced the incidence of preterm delivery and neonatal hypoglycemia. However, no difference was observed between 1.1 g MI per day plus 27.6 mg D-chiro-inositol (DCI) per day and the control group regarding all evaluated results. In conclusion, 4 g MI nutritional supplementation per day during early pregnancy may reduce GDM incidence and severity, therefore may be a practical and safe approach for the prevention of GDM.

Myo-inositol supplementation for the prevention of gestational diabetes: A meta-analysis of randomized controlled trials

INTRODUCTION

It is elusive to use myo-inositol supplementation to prevent gestational diabetes, and this meta-analysis aims to study the efficacy of myo-inositol supplementation for the prevention of gestational diabetes.

METHODS

Several databases including PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systemically searched from inception to October 2021, and we included the randomized controlled trials (RCTs) assessing the effect of myo-inositol supplementation on the incidence of gestational diabetes.

RESULTS

Seven eligible RCTs were included in this meta-analysis. Compared with control group in pregnant women, myo-inositol supplementation could lead to remarkably reduced incidence of gestational diabetes (OR = 0.32; 95% CI = 0.15 to 0.72; P = 0.005), reduced 2-h glucose OGTT (MD = -5.29; 95% CI = -10.24 to -0.34; P = 0.04), increased gestational age at birth (MD = 0.96; 95% CI = -1.67 to 3.87; P = 0.005) and decreased incidence of preterm delivery (OR = 0.35; 95% CI = 0.17 to 0.70; P = 0.003), but exhibited no obvious influence on birth weight (MD = -22.82; 95% CI = -121.95 to 76.32; P = 0.65).

CONCLUSIONS

Myo-inositol supplementation is recommended to prevent gestational diabetes with caution due to some heterogeneity.

The efficacy of myo-inositol supplementation to reduce the incidence of gestational diabetes: a meta-analysis

INTRODUCTION

Myo-inositol supplementation is used to reduce the incidence of gestational diabetes, but its efficacy is not well established. This meta-analysis aims to explore the influence of myo-inositol supplementation on the prevention of gestational diabetes.

METHODS

This meta-analysis has been conducted up to March 2022 to identify randomized clinical trials comparing the efficacy of myo-inositol supplementation to prevent gestational diabetes. Several databases including PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systemically.

RESULTS

We have included eight RCTs in this meta-analysis. Compared with control group in pregnant women, myo-inositol supplementation was found to significantly decrease the incidence of gestational diabetes (OR = 0.40; 95% CI = 0.19 to 0.84; p = .01), 2-h glucose OGTT (SMD = -0.22; 95% CI = -0.41 to -0.02; p = .03), HOMA-IR (SMD = -0.25; 95% CI = -0.42 to -0.08; p = .004) and preterm delivery (OR = 0.41; 95% CI = 0.23 to 0.73; p = .003), but demonstrated no obvious impact on gestational age at birth (SMD = 0.12; 95% CI = -0.05 to 0.29; p = .18) or birth weight (SMD = -0.04; 95% CI = -0.20 to 0.13; p = .68).

CONCLUSIONS

Myo-inositol supplementation is effective to reduce the incidence of gestational diabetes, 2-h glucose OGTT, HOMA-IR and preterm delivery, which suggested that myo-inositol supplementation should be recommended to prevent gestational diabetes.

Inositols, Probiotics, and Gestational Diabetes: Clinical and Epigenetic Aspects

There is growing interest in the potential role of different stereoisomers of inositol or their combination as well as probiotics supplementation in healthy glucose metabolism during pregnancy and in promoting offspring health. The aim of this review is to clarify the effects of several inositol and probiotics-based supplements in the prevention and treatment of gestational diabetes (GDM). Moreover, we will discuss the epigenetic aspects and their short- and long-term effects in response to probiotic intervention as well as the possible implications of these findings in guiding appropriate supplementation regimens in pregnancy.

Advances in non-hormonal pharmacotherapy for the treatment of male infertility: the role of inositols

INTRODUCTION

Several antioxidants are available for the treatment of male infertility. Although the benefit of myo-inositol (MYO) and D-chiro-inositol (DCI) for female infertility is recognized, their role in male infertility is a matter of debate.

AREAS COVERED

The authors review the impact that treatment with MYO and/or DCI may have on conventional and bio-functional sperm parameters [mitochondrial membrane potential (MMP), sperm chromatin compactness, and sperm DNA fragmentation (SDF)], seminal oxidative stress (OS) and pregnancy, miscarriage, and live birth rates, and the possible mechanisms involved. Furthermore, the authors gather evidence on the effects of MYO and/or DCI on sperm function in vitro.

EXPERT OPINION

MYO can improve sperm count, motility, capacitation, acrosome reaction, and MMP. No data are currently available on the effects of DCI in vivo. Both MYO and DCI ameliorate sperm motility and MMP in vitro. Therefore, the use of inositols should be preferred in patients with idiopathic asthenozoospermia, especially in case of impaired sperm mitochondrial function. Due to their insulin-sensitizing action, a role for these molecules may be envisaged for the treatment of infertility caused by carbohydrate metabolism derangement.

Analysis of Risk Factors for the Development of Gestational Diabetes Mellitus in a Group of Romanian Patients

INTRODUCTION

Gestational diabetes mellitus (GDM) is caused by numerous risk factors, the most common being old age, obesity, family history of diabetes mellitus, GDM, history of fetal macrosomia, history of polycystic ovary syndrome or treatment with particular drugs, multiple births, and certain races. The study proposed to analyze the risk factors causing GDM.

METHOD

In the study, we included 97 pregnant women to whom there was an OGTT performed between weeks 24th and 28th of pregnancy, divided into two groups, with GDM and without GDM. The statistical analysis was performed with SPSS 26.0, the tests being statistically significant if p value < 0.05.

RESULTS

The favoring risk factors for the onset of GDM were analyzed, with statistically significant differences between the GDM group and the group without GDM related to the delivery age (32.39 ± 4.66 years old vs. 28.61 ± 4.71 years old), history of fetal macrosomia (13.7% vs. 0%), presence of GDM during previous pregnancies (7.8% vs. 0%), HBP before pregnancy (9.8% vs. 0%), gestational HBP (17.6% vs. 0%), glycemia value at first medical visit (79.37 ± 9.34 mg/dl vs. 71.39 ± 9.16 mg/dl), and weight gain during pregnancy (14.61 ± 4.47 kg vs. 12.48 ± 5.87 kg).

CONCLUSIONS

Identifying the risk factors for the GDM onset has a special importance, implying an early implementation of interventional measures in order to avoid the onset of GDM and associated maternal and fetal complications.

[Research progress on the etiology and pathogenesis of spina bifida]

Objective

To review the research progress on etiology and pathogenesis of spina bifida.

Methods

By consulting relevant domestic and foreign research literature on spina bifida, the classification, epidemic trend, pathogenesis, etiology, prevention and treatment of it were analyzed and summarized.

Results

Spina bifida, a common phenotype of neural tube defects, is classified based on the degree and pattern of malformation associated with neuroectodermal involvement and is due to the disturbance of neural tube closure 28 days before embryonic development. The prevalence of spina bifida varies greatly among different ethnic groups and regions, and its etiology is complex. Currently, some spina bifida patients can be prevented by folic acid supplements, and with the improvement of treatment technology, the short-term and long-term survival rate of children with spina bifida has improved.

Conclusion

The research on the pathogenesis of spina bifida will be based on the refined individual information on exposure, genetics, and complex phenotype, and will provide a theoretical basis for improving prevention and treatment strategies through multidisciplinary cooperation.

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.

Melatonin and Myo-Inositol: Supporting Reproduction from the Oocyte to Birth

Human pregnancy is a sequence of events finely tuned by several molecular interactions that come with a new birth. The precise interlocking of these events affecting the reproductive system guarantees safe embryo formation and fetal development. In this scenario, melatonin and myo-inositol seem to be pivotal not only in the physiology of the reproduction process, but also in the promotion of positive gestational outcomes. Evidence demonstrates that melatonin, beyond the role of circadian rhythm management, is a key controller of human reproductive functions. Similarly, as the most representative member of the inositol’s family, myo-inositol is essential in ensuring correct advancing of reproductive cellular events. The molecular crosstalk mediated by these two species is directly regulated by their availability in the human body. To date, biological implications of unbalanced amounts of melatonin and myo-inositol in each pregnancy step are growing the idea that these molecules actively contribute to reduce negative outcomes and improve the fertilization rate. Clinical data suggest that melatonin and myo-inositol may constitute an optimal dietary supplementation to sustain safe human gestation and a new potential way to prevent pregnancy-associated pathologies.

Advances in the role of silence information regulator family in pathological pregnancy

Aberrant maternal inflammation and oxidative stress are the two main mechanisms of pathological pregnancy. The silence information regulator (sirtuin) family is a highly conserved family of nicotinamide adenine dinucleotide (NAD)-dependent deacylases. By regulating the post-translational modification of proteins, sirtuin is involved in various biological processes including oxidative stress and inflammation. Nowadays, emerging evidence indicates that sirtuin may be closely related to the occurrence and development of pathological pregnancy. The down-regulation of sirtuin can cause spontaneous preterm delivery by promoting uterine contraction and rupture of fetal membranes, cause gestational diabetes mellitus through promoting oxidative stress and affecting the activity of key enzymes in glucose metabolism, cause preeclampsia by reducing the proliferation and invasion ability of trophoblasts, cause intrahepatic cholestasis of pregnancy by promoting the production of bile acids and T helper 1 cell (Th1) cytokines, and cause intrauterine growth restriction through inducing mitochondrial dysfunction. Moreover, the expression and activation of sirtuin can be modulated through dietary interventions, thus sirtuin is expected to become a new target for the prevention and treatment of pregnancy complications. This article reviews the role of the sirtuin family in the occurrence and development of pathological pregnancy and its influence on the development of the offspring.

Myo-Inositol as a Key Supporter of Fertility and Physiological Gestation

Pregnancy is a complex process, featuring several necessary changes in women's physiology. Most women undergo healthy pregnancies; even so, several women experience reduced fertility or pathologies related to the pregnancy. In the last years, researchers investigated several molecules as promoters of fertility. Among all, myo-inositol (myo-ins) represents a safe compound that proved useful in issues related to fertility and pregnancy. In fact, myo-ins participates in several signaling processes, including the pathways of insulin and gonadotropins, and, therefore, it is likely to positively affect fertility. In particular, several clinical trials demonstrate that its administration can have therapeutic effects in infertile women, and that it can also be useful as a preventive treatment during pregnancy. Particularly, myo-ins could prevent the onset of neural tube defects and the occurrence of gestational diabetes mellitus, promoting a trouble-free gestation. Due to the safety and efficiency of myo-ins, such a treatment may also substitute several pharmaceuticals, which are contraindicated in pregnancy.

Impact of different stereoisomers of inositol on insulin sensitivity of gestational diabetes mellitus patients

BACKGROUND

Inositol is a hexa-carbon polyol, a naturally soluble vitamin, often found in various foods.

AIM

To discuss the impact of different stereoisomers of inositol on insulin sensitivity of gestational diabetes mellitus (GDM) patients.

METHODS

Eighty GDM pregnant women were divided into four groups according to their treatment received: A group (placebo folic acid 400 μg/d), B group [myo-inositol (MI) 1500 mg, twice a day], C group [D-chiro-inositol (DCI) 250 mg, twice a day], and D group (inositol MI and inositol DCI 1500 mg/250 mg, twice a day). Each patient routinely used dietary guidance adjustments and did some safe and effective aerobic exercise in addition to receiving placebo or inositol from GDM diagnosis to delivery. Triglyceride, total cholesterol, fasting plasma glucose, oral glucose tolerance test postprandial glucose (2 h postprandial blood glucose), fasting insulin, fasting plasma glucose, and glycosylated hemoglobin levels and Homeostasis Model Assessment-insulin resistance (HOMA-IR) and Homeostasis Model Assessment-insulin sensitivity index (HOMA-ISI) scores were determined before treatment and 8 wk after treatment onset. Adverse maternal and infant outcomes, including hypoglycemia, excessive amniotic fluid, premature infants, macrosomia, fetal distress etc., were also recorded.

RESULTS

There was no statistical difference in the baseline data of each group. The levels of 2 h blood glucose, glycosylated hemoglobin, fasting insulin, total cholesterol, and triglyceride in the B, C, and D groups were significantly lower than those in the control group (A group) after treatment (P < 0.05). Moreover, compared with the B group, the level of the above indexes in the C and D groups decreased more significantly, and the differences were statistically significant (P < 0.05). The HOMA-IR of B, C, and D groups decreased significantly, and the HOMA-ISI increased significantly compared with the A group, and the differences were statistically significant (P < 0.05), among which the decrease of HOMA-IR and the increase of HOMA-ISI were more significant in the C and D group compared with the B group (P < 0.05). The occurrence rate of adverse maternal and infant outcomes in the C and D group was significantly lower than that in the control group (A group), and the differences were statistically significant (P < 0.05).

CONCLUSION

Treatment with different inositol stereoisomers (inositol MI and inositol DCI) can improve insulin sensitivity and reduce insulin resistance in diabetic patients, and inositol DCI has a better curative effect than inositol MI.