Myo-inositol may prevent gestational diabetes in PCOS women

Higher early pregnancy plasma myo-inositol associates with increased postprandial glycaemia later in pregnancy: Secondary analyses of the NiPPeR randomized controlled trial

AIM

Myo-inositol supplementation from ~13 weeks' gestation reportedly improves glycaemia regulation in metabolically at-risk women, with speculation that earlier supplementation might bring further improvement. However, the NiPPeR trial of a myo-inositol-containing supplement starting preconception did not lower gestational glycaemia in generally healthy women. We postulated that the earlier timing of supplementation influences the maternal metabolic adaptation for gestational glycaemia regulation.

METHODS

In total, 585 women were recruited from Singapore, UK and New Zealand for the NiPPeR study. We examined associations of plasma myo-inositol concentrations at 7 and 28 weeks' gestation with 28 weeks plasma glucose (PG; fasting, and 1 h and 2 h in 75 g oral glucose tolerance test) and insulin indices using linear regression adjusting for covariates.

RESULTS

Higher 7-week myo-inositol, but not 28-week myo-inositol, associated with higher 1 h PG [βadj (95% confidence intervals) 0.05 (0.01, 0.09) loge mmol/L per loge μmol/L, p = .022] and 2 h PG [0.08 (0.03, 0.12), p = .001]; equivalent to 0.39 mmol/L increase in 2 h PG for an average 7-week myo-inositol increase of 23.4 μmol/L with myo-inositol supplementation. Higher 7-week myo-inositol associated with a lower 28-week Stumvoll index (first phase), an approximation of insulin secretion [-0.08 (-0.15, -0.01), p = .020] but not with 28-week Matsuda insulin sensitivity index. However, the clinical significance of a 7-week myo-inositol-related increase in glycaemia was limited as there was no association with gestational diabetes risk, birthweight and cord C-peptide levels. In-silico modelling found higher 28-week myo-inositol was associated with lower gestational glycaemia in White, but not Asian, women after controlling for 7-week myo-inositol effects.

CONCLUSION

To our knowledge, our study provides the first evidence that increasing first trimester plasma myo-inositol may slightly exacerbate later pregnancy post-challenge glycaemia, indicating that the optimal timing for starting prenatal myo-inositol supplementation needs further investigation.

The role of myo-inositol supplement in assisted reproductive techniques

Assisted reproductive techniques can help many infertile couples conceive. Therefore, there is a need for an effective method to overcome the widespread problems of infertile men and women. Oocyte and sperm quality can increase the chances of successful in vitro fertilisation. The maturation environment in which gametes are present can affect their competency for fertilisation. It is well established that myo-inositol (MI) plays a pivotal role in reproductive physiology. It participates in cell membrane formation, lipid synthesis, cell proliferation, cardiac regulation, metabolic alterations, and fertility. This molecule also acts as a direct messenger of insulin and improves glucose uptake in various reproductive tissues. Evidence suggests that MI regulates events such as gamete maturation, fertilisation, and embryo growth through intracellular Ca2 + release and various signalling pathways. In addition to the in-vivo production of MI from glucose in the reproductive organs, its synthesis by in vitro-cultured sperm and follicles has also been reported. Therefore, MI is suggested as a therapeutic approach to maintain sperm and oocyte health in men and women with reproductive disorders and individuals of reproductive age.

Antenatal dietary supplementation with myo-inositol for preventing gestational diabetes

BACKGROUND

Gestational diabetes with onset or first recognition during pregnancy is an increasing problem worldwide. Myo-inositol, an isomer of inositol, is a naturally occurring sugar commonly found in cereals, corn, legumes and meat. Myo-inositol is one of the intracellular mediators of the insulin signal and correlates with insulin sensitivity in type 2 diabetes. The potential beneficial effect of improving insulin sensitivity suggests that myo-inositol may be useful for women in preventing gestational diabetes. This is an update of a review first published in 2015.

OBJECTIVES

To assess if antenatal dietary supplementation with myo-inositol is safe and effective, for the mother and fetus, in preventing gestational diabetes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, WHO ICTRP (17 March 2022) and the reference lists of retrieved studies.

SELECTION CRITERIA

We included published and unpublished randomised controlled trials (RCTs) including cluster-RCTs and conference abstracts, assessing the effects of myo-inositol for the prevention of gestational diabetes in pregnant women. We included studies that compared any dose of myo-inositol, alone or in a combination preparation, with no treatment, placebo or another intervention. Quasi-randomised and cross-over trials were not eligible. We excluded women with pre-existing type 1 or type 2 diabetes.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, assessed risk of bias and extracted the data. We checked the data for accuracy. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included seven RCTs (one conducted in Ireland, six conducted in Italy) reporting on 1319 women who were 10 weeks to 24 weeks pregnant at the start of the studies. The studies had relatively small sample sizes and the overall risk of bias was low. For the primary maternal outcomes, meta-analysis showed that myo-inositol may reduce the incidence of gestational diabetes (risk ratio (RR) 0.53, 95% confidence interval (CI) 0.31 to 0.90; 6 studies, 1140 women) and hypertensive disorders of pregnancy (RR 0.34, 95% CI 0.19 to 0.61; 5 studies, 1052 women). However, the certainty of the evidence was low to very low. For the primary neonatal outcomes, only one study measured the risk of a large-for-gestational-age infant and found myo-inositol was associated with both appreciable benefit and harm (RR 1.40, 95% CI 0.65 to 3.02; 1 study, 234 infants; low-certainty evidence). None of the included studies reported on the other primary neonatal outcomes (perinatal mortality, mortality or morbidity composite). For the secondary maternal outcomes, we are unclear about the effect of myo-inositol on weight gain during pregnancy (mean difference (MD) -0.25 kilogram (kg), 95% CI -1.26 to 0.75 kg; 4 studies, 831 women) and perineal trauma (RR 4.0, 95% CI 0.45 to 35.25; 1 study, 234 women) because the evidence was assessed as being very low-certainty. Further, myo-inositol may result in little to no difference in caesarean section (RR 0.91, 95% CI 0.77 to 1.07; 4 studies, 829 women; low-certainty evidence). None of the included studies reported on the other secondary maternal outcomes (postnatal depression and the development of subsequent type 2 diabetes mellitus). For the secondary neonatal outcomes, meta-analysis showed no neonatal hypoglycaemia (RR 3.07, 95% CI 0.90 to 10.52; 4 studies; 671 infants; very low-certainty evidence). However, myo-inositol may be associated with a reduction in the incidence of preterm birth (RR 0.35, 95% CI 0.17 to 0.70; 4 studies; 829 infants). There were insufficient data for a number of maternal and neonatal secondary outcomes, and no data were reported for any of the long-term childhood or adulthood outcomes, or for health service utilisation outcomes.

AUTHORS' CONCLUSIONS

Evidence from seven studies shows that antenatal dietary supplementation with myo-inositol during pregnancy may reduce the incidence of gestational diabetes, hypertensive disorders of pregnancy and preterm birth. Limited data suggest that supplementation with myo-inositol may not reduce the risk of a large-for-gestational-age infant.  The current evidence is based on small studies that were not powered to detect differences in outcomes such as perinatal mortality and serious infant morbidity. Six of the included studies were conducted in Italy and one in Ireland, which raises concerns about the lack of generalisability to other settings. There is evidence of inconsistency among doses of myo-inositol, the timing of administration and study population. As a result, we downgraded the certainty of the evidence for many outcomes to low or very low certainty. Further studies for this promising antenatal intervention for preventing gestational diabetes are encouraged and should include pregnant women of different ethnicities and varying risk factors. Myo-inositol at different doses, frequency and timing of administration, should be compared with placebo, diet and exercise, and pharmacological interventions. Long-term follow-up should be considered and outcomes should include potential harms, including adverse effects.

Myo-inositol oxygenese activity in second trimester of pregnancy: altered myoinositol catabolism in gestational diabetes mellitus

OBJECTIVE

We aimed to determine myo-inositol oxygenase (MIOX) activity in gestational diabetes mellitus (GDM).

MATERIAL AND METHODS

The insulin, HbA1c, and MIOX levels of 80 pregnant women were analysed after 75 g OGTT. Group I included patients with no risk factor for GDM, Group II: patients with high risk for GDM, and Group III: GDM patients.

RESULTS

Fasting plasma glucose and Homeostatic Model Assessment for Insulin Resistance index were significantly higher in GDM cases (Group 3). Regarding the MIOX levels, significantly higher levels were recorded at 0-h in Group 3 compared to Groups 1 and 2. Significant alteration in MIOX activity was found between 0- and 2-h in Group 3 compared to Groups 1 and 2 (p < .029).

CONCLUSIONS

MIOX levels were higher in GDM cases so, it may be have a role in myo-inositol catabolism.

Evidence based recommendations for an optimal prenatal supplement for women in the US: vitamins and related nutrients

The blood levels of most vitamins decrease during pregnancy if un-supplemented, including vitamins A, C, D, K, B1, B3, B5, B6, folate, biotin, and B12. Sub-optimal intake of vitamins from preconception through pregnancy increases the risk of many pregnancy complications and infant health problems. In the U.S., dietary intake of vitamins is often below recommended intakes, especially for vitamin D, choline and DHA. Many studies suggest that insufficient vitamin intake is associated with a wide range of pregnancy complications (anemia, Cesarean section, depression, gestational diabetes, hypertension, infertility, preeclampsia, and premature rupture of membranes) and infant health problems (asthma/wheeze, autism, low birth weight, congenital heart defects, intellectual development, intrauterine growth restriction, miscarriage, neural tube defects, orofacial defects, and preterm birth). The primary goal of this paper is to review the research literature and propose evidence-based recommendations for the optimal level of prenatal supplementation for each vitamin for most women in the United States. A secondary goal was to compare these new recommendations with the levels of vitamins in over 180 commercial prenatal supplements. The analysis found that prenatal supplements vary widely in content, often contained only a subset of essential vitamins, and the levels were often below our recommendations. This suggests that increasing prenatal vitamin supplementation to the levels recommended here may reduce the incidence of many pregnancy complications and infant health problems which currently occur.

In vivo metabolizable branched poly(ester amide) based on inositol and amino acids as a drug nanocarrier for cancer therapy

Amino acid-based poly(ester amide) (PEA) has been utilized for various biomedical applications due to its tunable mechanical properties, good biocompatibility, and biodegradability. However, bioactive components have rarely been incorporated into the PEA structure, and there has been no systematic investigation of amino acid-based PEAs with branched structures. Herein, an in vivo metabolizable branched poly(ester amide) (BPEA) was synthesized from inositol (a natural growth factor) and amino acids for drug delivery in cancer therapy. The bioactive components, inositol, arginine, and phenylalanine, could improve the biocompatibility of the BPEA nanocarrier, and convert into other valuable biomolecules (phosphatidylinositol for cell signaling, functional protein, or other amino acids including ornithine, citrulline, and tyrosine) after accomplishing drug delivery and biodegradation. Paclitaxel (PTX) was encapsulated into BPEA nanocarriers to formulate drug-loaded BPEA nanoparticles (BPEA@PTX NPs). In vitro results indicated that BPEA@PTX NPs had a sub 100 nm size and could effectively inhibit the growth and migration of cancer cells. In vivo experiments further demonstrated significant suppression of tumor size compared with that with free PTX. Both in vitro and in vivo results confirmed the superior biosafety of BPEA, indicating that BPEA exhibits excellent biocompatibility and considerable potential as a drug carrier.

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.

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

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.

Efficacy of myoinositol in treatment of gestational diabetes mellitus in Asian Indian women: A pilot randomized clinical trial

OBJECTIVE

To compare efficacy of myoinositol as an adjuvant to dietary modification for treatment of gestational diabetes mellitus in Asian Indian women compared to controls.

STUDY DESIGN

Setting: This pilot randomized open label trial was conducted in a single antenatal clinic in India.

SUBJECTS

One hundred women with singleton pregnancy and gestational diabetes diagnosed between 14-28 weeks' gestation were included. Overt diabetes, twin pregnancy, pre-existing renal disease, heart disease and other chronic medical disorders were exclusions.

INTERVENTION

Participants were randomized in two groups (1:1 ratio) by opaque envelope method. Individualized nutrition counseling with dietary modification and routine antenatal care was provided to all. Fifty women received myoinositol 1000 mg twice daily; 50 controls did not receive myoinositol. Fasting and postprandial glucose levels were assessed after two weeks. Women not achieving glycemic targets (fasting glucose <95 and postprandial glucose <120 mg/dL) were given pharmacologic therapy. Contributory factors in women requiring additional pharmacologic therapy, maternal and fetal outcomes were noted.

STATISTICAL ANALYSIS

Between group comparisons reported relative risk and mean difference. To assess predictive factors for need for pharmacologic therapy, univariate and multivariable logistic regression analysis were used.

RESULTS

Baseline characteristics were comparable in both groups. Except one woman in the myoinositol group, all women provided glycaemia data throughout their pregnancy. Glycemic control was achieved in 44/ 49 (89.8 %) women in myoinositol group which was significantly higher than 34/50 (68 %) in the controls ((relative risk 0.31, 95 % confidence interval 0.13 to 0.80, p = 0.008). Mean duration of myoinositol treatment was 17.6 weeks (standard deviation 5.3). Additional treatment with metformin/insulin was needed in all women failing to achieve glycaemic control. The mean (range) dose of insulin was 25.3 units in myoinositol group compared to 14.27 units in controls (p = 0.058). Secondary outcomes were similar in two groups except baby weight which was higher in controls (p = 0.018).

CONCLUSIONS

Oral supplementation with myoinositol in dose of 1 gm twice-daily, when started soon after the diagnosis of GDM, is effective in achieving glycemic control and decreasing the need for additional pharmacological therapy in Asian Indian women.

An Update of Medical Nutrition Therapy in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a serious and frequent pregnancy complication that can lead to short and long-term risks for both mother and fetus. Different health organizations proposed different algorithms for the screening, diagnosis, and management of GDM. Medical Nutrition Therapy (MNT), together with physical exercise and frequent self-monitoring, represents the milestone for GDM treatment in order to reduce maternal and fetal complications. The pregnant woman should benefit from her family support and make changes in their lifestyles, changes that, in the end, will be beneficial for the whole family. The aim of this manuscript is to review the literature about the Medical Nutrition Therapy in GDM and its crucial role in GDM management.

A review of the role of inositols in conditions of insulin dysregulation and in uncomplicated and pathological pregnancy

Inositols, a group of 6-carbon polyols, are highly bioactive molecules derived from diet and endogenous synthesis. Inositols and their derivatives are involved in glucose and lipid metabolism and participate in insulin-signaling, with perturbations in inositol processing being associated with conditions involving insulin resistance, dysglycemia and dyslipidemia such as polycystic ovary syndrome and diabetes. Pregnancy is similarly characterized by substantial and complex changes in glycemic and lipidomic regulation as part of maternal adaptation and is also associated with physiological alterations in inositol processing. Disruptions in maternal adaptation are postulated to have a critical pathophysiological role in pregnancy complications such as gestational diabetes and pre-eclampsia. Inositol supplementation has shown promise as an intervention for the alleviation of symptoms in conditions of insulin resistance and for gestational diabetes prevention. However, the mechanisms behind these affects are not fully understood. In this review, we explore the role of inositols in conditions of insulin dysregulation and in pregnancy, and identify priority areas for research. We particularly examine the role and function of inositols within the maternal-placental-fetal axis in both uncomplicated and pathological pregnancies. We also discuss how inositols may mediate maternal-placental-fetal cross-talk, and regulate fetal growth and development, and suggest that inositols play a vital role in promoting healthy pregnancy.

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

INTRODUCTION

Obstetric history and maternal body composition and lifestyle may be associated with serious complications both for the mother, such as gestational diabetes mellitus (GDM), and for the fetus, including congenital malformations such as neural tube defects (NTDs).

AREAS COVERED

In view of the recent knowledge, changes in nutritional and physical activity habits ameliorate glycemic control during pregnancy and in turn improve maternal and neonatal health outcomes. Recently, a series of small clinical and experimental studies indicated that supplemenation with inositols, a family of insulin sensitizers, was associated with beneficial impact for both GDM and NTDs.

EXPERT OPINION

Herein, we discuss the most significant scientific evidence supporting myo-inositol administration as a prophylaxis for the above-mentioned conditions.

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.

Effect of dietary myo-inositol supplementation on the insulin resistance and the prevention of gestational diabetes mellitus: study protocol for a randomized controlled trial

Background

Gestational diabetes mellitus (GDM) is defined as impaired glucose tolerance with onset or first recognition during pregnancy, which is characterized by an increased insulin resistance. Gestational diabetes mellitus is associated with pregnancy-related maternal and fetal morbidity (both antenatal and perinatal).

Myo-inositol has been suggested to improve insulin resistance in women with polycystic ovary syndrome.

The aim of this study is to examine the impact of myo-inositol supplementation during pregnancy on the incidence of gestational diabetes mellitus.

Methods

We will conduct a single-center, open-label, randomized controlled trial. A total of 160 healthy pregnant women with singleton pregnancy at 11–13⁺⁶ weeks of gestation will be randomly allocated in two groups: intervention group (N = 80) and control group (N = 80). The intervention group will receive myo-inositol and folic acid (4000 mg myo-inositol and 400 mcg folic acid daily) from 11 to 13⁺⁶ weeks of gestation until 26–28 weeks of gestation, while the control group will receive folic acid alone (400 mcg folic acid daily) for the same period of time as intervention group. The primary outcome will be gestational diabetes incidence rate at 26–28 weeks of gestation, according to the results of a 75 g oral glucose tolerance test held at 26–28 weeks of gestation. The secondary outcomes will include fasting blood glucose levels, glycated hemoglobin levels, insulin resistance level (evaluated by homeostasis model assessment of insulin resistance and Matsuda Index), and incidence rate of diet-treated gestational diabetes and diabetes requiring insulin therapy at 26–28 weeks of gestation.

Discussion

This trial will provide evidence for the effectiveness of myo-inositol supplementation during pregnancy in reducing the incidence of gestational diabetes mellitus.

Trial registration

ISRCTN registry: ISRCTN16142533. Registered on 9 March 2017.

High placental inositol content associated with suppressed pro-adipogenic effects of maternal glycaemia in offspring: the GUSTO cohort

Background/Objectives

Maternal glycaemia promotes fetal adiposity. Inositol, an insulin sensitizer, has been trialled for gestational diabetes prevention. The placenta has been implicated in how maternal hyperglycaemia generates fetal pathophysiology, but no studies have examined whether placental inositol biology is altered with maternal hyperglycaemia, nor whether such alterations impact fetal physiology. We aimed to investigate whether the effects of maternal glycaemia on offspring birthweight and adiposity at birth differed across placental inositol levels.

Methods

Using longitudinal data from the Growing Up in Singapore Towards healthy Outcomes cohort, maternal fasting glucose (FPG) and 2-hour plasma glucose (2hPG) were obtained in pregnant women by a 75-g oral glucose tolerance test around 26 weeks’ gestation. Relative placental inositol was quantified by liquid chromatography-mass spectrometry. Primary outcomes were birthweight (n = 884) and abdominal adipose tissue (AAT) volumes measured by neonatal MRI scanning in a subset (n = 262) of term singleton pregnancies. Multiple linear regression analyses were performed.

Results

Placental inositol was lower in those with higher 2hPG, no exposure to tobacco smoke antenatally, with vaginal delivery and shorter gestation. Positive associations of FPG with birthweight (adjusted β [95% CI] 164.8 g [109.1, 220.5]) and AAT (17.3 ml [11.9, 22.6] per mmol glucose) were observed, with significant interactions between inositol tertiles and FPG in relation to these outcomes (p < 0.05). Stratification by inositol tertiles showed that each mmol/L increase in FPG was associated with increased birthweight and AAT volume among cases within the lowest (birthweight = 174.2 g [81.2, 267.2], AAT = 21.0 ml [13.1, 28.8]) and middle inositol tertiles (birthweight = 202.0 g [103.8, 300.1], AAT = 19.7 ml [9.7, 29.7]). However, no significant association was found among cases within the highest tertile (birthweight = 81.0 g [−21.2, 183.2], AAT = 0.8 ml [−8.4, 10.0]).

Conclusions

High placental inositol may protect the fetus from the pro-adipogenic effects of maternal glycaemia. Studies are warranted to investigate whether prenatal inositol supplementation can increase placental inositol and reduce fetal adiposity.

Diet and Nutritional Interventions with the Special Role of Myo-Inositol in Gestational Diabetes Mellitus Management. An Evidence-Based Critical Appraisal

BACKGROUND

Gestational Diabetes Mellitus (GDM), defined as glucose intolerance with onset or first recognition during pregnancy, represents one of the most common maternal-fetal complications during pregnancy and it is associated with poor perinatal outcomes. To date, GDM is a rising condition over the last decades coinciding with the ongoing epidemic of obesity and Type 2 Diabetes Mellitus (T2DM).

OBJECTIVE

The aim of this review is to discuss the role of diet and nutritional interventions in preventing GDM with the explanation of the special role of myo-inositol (MI) in this matter.

METHODS

We performed an overview of the most recent literature data on the subject with particular attention to the effectiveness of diet and nutritional interventions in the prevention of GDM with the special role of MI.

RESULTS

Nutritional intervention and physical activity before and during pregnancy are mandatory in women affected by GDM. Moreover, the availability of insulin-sensitizers such as different forms of inositol has dramatically changed the scenario, allowing the treatment of several metabolic diseases, such as those related to glucose dysbalance. Although the optimal dose, frequency, and form of MI administration need to be further investigated, diet supplementation with MI appears to be an attractive alternative for the GDM prevention as well as for the reduction of GDM-related complications.

CONCLUSIONS

More studies should be conducted to prove the most effective nutritional intervention in GDM. Regarding the potential effectiveness of MI, further evidence in multicenter, randomized controlled trials is needed to draw firm conclusions.

Myo-Inositol for the Prevention of Gestational Diabetes Mellitus. A Brief Review

Gestational Diabetes Mellitus (GDM) is one of the most frequent complications of pregnancy and is characterized by a carbohydrate intolerance which is diagnosed with the oral glucose tolerance test. The prevalence of GDM in our population is about 12%, but risk factors like a previous GDM, ethnicity, a parent with diabetes mellitus type 2 and maternal overweight may increase its occurrence. Complications of GDM are a pre-term birth (before 37 wk gestation), macrosomia (birth weight ≥4 kg) and gestational hypertension. Actually, GDM is principally treated with diet and, if it is necessary, with insulin; but the challenge is the prevention of GDM. Among the measures used, changes in life-style (diet+exercise) failed to prevent GDM whereas metformin showed conflicting results. A promising supplement is myo-inositol (MI) which was given from first trimester until delivery to women at risk for GDM reporting a significant decrease in GDM occurrence by more than 60% comparing to the placebo group. Recently, a secondary analysis from 3 randomized controlled trials demonstrated that MI may also significantly reduce some of GDM complications such as pre-term birth and macrosomia with a favorable impact on mother and fetus well being.

A review of therapeutic options for managing the metabolic aspects of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. Metabolic sequelae associated with PCOS range from insulin resistance to type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Insulin resistance plays a significant role in the pathophysiology of PCOS and it is a reliable marker for cardiometabolic risk. Although insulin sensitising agents such as metformin have been traditionally used for managing metabolic aspects of PCOS, their efficacy is low in terms of weight reduction and cardiovascular risk reduction compared with newer agents such as incretin mimetics and SGLT2 inhibitors. With current pharmaceutical advances, potential therapeutic options have increased, giving patients and clinicians more choices. Incretin mimetics are a promising therapy with a unique metabolic target that could be used widely in the management of PCOS. Likewise, bariatric procedures have become less invasive and result in effective weight loss and the reversal of metabolic morbidities in some patients. Therefore, surgical treatment targeting weight loss becomes increasingly common in the management of obese women with PCOS. Newer emerging therapies, including twincretins, triple GLP-1 agonists, glucagon receptor antagonists and imeglemin, are promising therapeutic options for treating T2DM. Given the similarity of metabolic and pathological features between PCOS and T2DM and the variety of therapeutic options, there is the potential to widen our strategy for treating metabolic disorders in PCOS in parallel with current therapeutic advances. The review was conducted in line with the recommendations from the international evidence-based guideline for the assessment and management of polycystic ovary syndrome 2018.

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

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.

Inositol Supplementation in the Prevention of Gestational Diabetes Mellitus

Inositol, an emerging novel therapy for the treatment of gestational diabetes mellitus (GDM), is a cyclic polyol that has insulin-like effects and plays an important role in glucose homeostasis. The conventional treatment of GDM with insulin and oral antihyperglycemic drugs usually comes with side effects, paving the way for and shedding spotlight on clinical trials involving inositol. This review analyzed a host of recent trials that involved inositol supplementation for preventing GDM and their positive outcomes in reducing the rate of GDM among obese and overweight pregnant women, as well as women with polycystic ovarian syndrome (PCOS) or a family history of type 2 diabetes mellitus.

Nutritional Supplementation for the Prevention and/or Treatment of Gestational Diabetes Mellitus

PURPOSE OF REVIEW

Gestational diabetes mellitus (GDM) is a common pregnancy complication that has short- and long-term health implications for both the mother and child. While lifestyle modifications, insulin therapy, and oral agents such as metformin are effective, they can be difficult to adhere to, and there remain concerns over long-term effects of oral agents on the infant. Further, GDM has no proven preventive strategies, which could be more effective than treatment postdiagnosis. Nutritional supplements are an appealing, potentially safer, and better tolerated alternative to pharmaceuticals to treat and/or prevent GDM. Here, we review the existing evidence for nutritional supplementation for treatment and prevention of GDM.

RECENT FINDINGS

There is limited evidence that myo-inositol, vitamins D and B6, magnesium, selenium, zinc, fatty acids, and probiotics might be beneficial for the prevention or treatment of GDM. There are very few studies for each nutrient, and the existing studies tend to have few participants. Where multiple studies of a nutrient exist, often those studies were conducted within the same country, limiting the generalizability of the findings, or alternatively there was no consensus across findings. There is limited evidence that nutritional supplementation of myo-inositol, vitamins D and B6, magnesium, selenium, zinc, fatty acids, and probiotics could improve glycemic control or prevent GDM. Our understanding is constrained by the small number of studies, small sample sizes in most studies, and by lack of consistency across findings. Further large, high-quality, randomized controlled trials are required to determine the efficacy of nutritional supplements to treat or prevent GDM.

Drugs to Control Diabetes During Pregnancy

Diabetes is a common complication of pregnancy associated with both short- and long-term adverse maternal and offspring effects. All types of diabetes in pregnancy are increasing in prevalence. Treatment of diabetes in pregnancy, targeting glycemic control, improves both maternal and offspring outcomes, albeit imperfectly for many women. Pharmacologic treatment recommendations differ between pregestational and gestational diabetes. Improved treatment of diabetes in pregnancy will need to consider maternal disease heterogeneity and comorbidities as well as long-term offspring outcomes. In this review, the authors summarize recent clinical studies to highlight established pharmacologic treatments for diabetes in pregnancy and provide suggestions for further research.

Myoinositol in the Prevention of Gestational Diabetes Mellitus: Is It Sensible?

Gestational diabetes mellitus (GDM) is a complication that increasingly affects pregnant women. Due to the risk of adverse outcomes in the mother as well as in the fetus which is caused by GDM, appropriate diagnosis and treatment is very essential. Nevertheless, it is important to find new, effective ways of prevention of GDM to avoid side effects. A promising example of such an action may be supplementation of myoinositol. As shown in studies, myoinositol may reduce the risk of developing gestational diabetes mellitus by improving insulin sensitivity.

Metformin therapy before conception versus throughout the pregnancy and risk of gestational diabetes mellitus in women with polycystic ovary syndrome: a systemic review, meta-analysis and meta-regression

The results of studies that assessed the impact of metformin treatments on gestational diabetes mellitus (GDM) in patients with polycystic ovary syndrome (PCOS) are inconclusive. In addition, the impact of time and duration of metformin therapy for an optimum reduction of GDM has not been reported in these studies. This study aimed to summarize current knowledge regarding the effect of metformin-therapy before conception versus throughout pregnancy on the risk of GDM in women with PCOS. PubMed, Scopus, Google Scholar and ScienceDirect databases were searched to identify relevant studies. Both fixed and random effect models were used. Subgroup analyses were performed based on the on the study methodology. The association between the PCOS status and GDM was assessed using the univariate and multiple meta-regression analysis adjusted by the BMI and metformin therapy. Forty-eight of 1397 identified studies were included involving 5711 PCOS patients and 20,296 controls. Regardless of metformin therapy, the prevalence of GDM diagnosed in the second trimester among women with PCOS was significantly higher than healthy controls that was independent of obesity. Including all studies, the increased risk of GDM among women with PCOS, compared to healthy controls, disappeared after the adjustment of metformin-therapy (β = 0.08, 95% CI 0.04, 0.2; p = 0.624). By excluding observational studies as a source of bias, the prevalence of GDM among women with PCOS treated using metformin before conception till the end of pregnancy did not differ from treated just before conception (β = - 0.09, 95% CI - 0.2, 0.02; p = 0.092) or those without metformin therapy (β = - 0.05, 95% CI - 0.07, 0.04; p = 0.301). The results remained unchanged after the subgroup analysis based on the methodology of RCTs and non-RCTs studies. The main body of literature in the current meta-analysis was observational, which may be mixed with some sources of bias. Also, a lack of well-designed and high quality interventional studies means that the findings should be interpreted with cautious. In this respect, decisions regarding the continuation or discontinuation of metformin therapy in women with PCOS are somewhat arbitrary and can be made individually based on the patient's condition given the presence or absence of other GDM risk factors. Additional well-designed RCTs still need for precise recommendation.

The influence of different inositol stereoisomers supplementation in pregnancy on maternal gestational diabetes mellitus and fetal outcomes in high-risk patients: a randomized controlled trial

Objective: To identify the effects of different dietary inositol stereoisomers on insulin resistance and the development of gestational diabetes mellitus (GDM) in women at high risk for this disorder.Design: A preliminary, prospective, randomized, placebo controlled clinical trial.Participants: Nonobese singleton pregnant women with an elevated fasting glucose in the first or early second trimester were studied throughout pregnancy.Intervention: Supplementation with myo-inositol, d-chiro-inositol, combined myo- and d-chiro-inositol or placebo.Main outcome measure: Development of GDM on a 75 grams oral glucose tolerance test at 24-28 weeks' gestation. Secondary outcome measures were increase in BMI, need for maternal insulin therapy, macrosomia, polyhydramnios, neonatal birthweight and hypoglycemia.Results: The group of women allocated to receive myo-inositol alone had a lower incidence of abnormal oral glucose tolerance test (OGTT). Nine women in the control group (C), one of the myo-inositol (MI), five in d-chiro-inositol (DCI), three in the myo-inositol/D-chiro-inositol group (MI/DCI) required insulin (p = .134). Basal, 1-hour, and 2 hours glycemic controls were significantly lower in exposed groups (p < .001, .011, and .037, respectively). The relative risk reduction related to primary outcome was 0.083, 0.559, and 0.621 for MI, DCI, and MI/DCI groups.Conclusions: This study compared the different inositol stereoisomers in pregnancy to prevent GDM. Noninferiority analysis demonstrated the largest benefit in the myo-inositol group. The relevance of our findings is mainly related to the possibility of an effective approach in GDM. Our study confirmed the efficacy of inositol supplementation in pregnant women at risk for GDM.

Clinical and metabolic outcomes in pregnant women at risk for gestational diabetes mellitus supplemented with myo-inositol: a secondary analysis from 3 RCTs

BACKGROUND

Gestational diabetes mellitus is defined as carbohydrate intolerance that begins or is first recognized during pregnancy. Insulin sensitizing substances such as myo-inositol have been considered for the prevention of gestational diabetes mellitus and related complications.

OBJECTIVE

Because previous studies failed to show a clear reduction of gestational diabetes mellitus complications, the aim of this study was to evaluate clinical and metabolic outcomes in women who are at risk for gestational diabetes mellitus supplemented with myo-inositol since the first trimester.

STUDY DESIGN

A secondary analysis of databases from 3 randomized, controlled trials (595 women enrolled) in which women who were at risk for gestational diabetes mellitus (a parent with type 2 diabetes mellitus, obese, or overweight) were supplemented with myo-inositol (4 g/d) throughout pregnancy. Main measures were the rate of adverse clinical outcomes: macrosomia (birthweight, ≥4000 g), large-for-gestational-age babies (fetal growth, ≥90 percentile), fetal growth restriction (fetal growth, ≤3 percentile), preterm birth (delivery before week 37 since the last menstruation), gestational hypertension, and gestational diabetes mellitus.

RESULTS

A significant reduction was observed for preterm birth (10/291 [3.4%] vs 23/304 [7.6%]; P=.03), macrosomia (6/291 [2.1%] vs 16/304 [5.3%]; P=.04), Large-for-gestational-age babies (14/291 [4.8%] vs 27/304 [8.9%]; P=.04) with only a trend to significance for gestational hypertension (4/291 [1.4%] vs 12/304 [3.9%]; P=.07). Gestational diabetes mellitus diagnosis was also decreased when compared with the control group (32/291 [11.0%] vs 77/304 [25.3%]; P<.001). At univariate logistic regression analysis, myo-inositol treatment reduced the risk for preterm birth (odds ratio, 0.44; 95% confidence interval, 0.20-0.93), macrosomia (odds ratio, 0.38; 95% confidence interval, 0.14-0.98), and gestational diabetes mellitus diagnosis (odds ratio, 0.36; 95% confidence interval, 0.23-0.57).

CONCLUSION

Myo-inositol treatment in early pregnancy is associated with a reduction in the rate of gestational diabetes mellitus and in the risk of preterm birth and macrosomia in women who are at risk for gestational diabetes mellitus.

The use of inositol(s) isomers in the management of polycystic ovary syndrome: a comprehensive review

The aim of this review is to present the current data about the role of inositols in the management of polycystic ovary syndrome (PCOS) women and in the prevention and treatment of gestational diabetes mellitus (GDM). We analyzed the available literature with key words PCOS, Myo-inositol, D-chiro-inositol, assisted reproductive technologies and GDM. The most recent literature would suggest that Myo-inositol, D-chiro-inositol and their combination in physiological ratio 40:1 could represent an important therapeutic strategy for the improvement of metabolic, hormonal and reproductive aspects of PCOS. In assisted reproductive technologies, however, myo-inositol and the combined treatment, despite D-chiro-inositol monotherapy, are able to improve clinical outcomes. Myo-inositol monotherapy results more effective in preventing and treating GDM even if a larger cohort of studies is needed to better clarify these results.

Polycystic ovary syndrome and adverse pregnancy outcomes: Current state of knowledge, challenges and potential implications for practice

Although there is a growing body of literature reporting that pregnancies in women with polycystic ovary syndrome (PCOS) are associated with greater complications than those without PCOS, methodological differences across studies make these results difficult to consolidate. This narrative review outlines potential mechanisms involved in adverse pregnancy outcomes in PCOS and the nature of the complications. It covers limitations of current evidence and future research directions. Future research should include prospective studies with phenotypic stratification of PCOS and matching or consideration of specific PCOS manifestations and risk factors specific to each pregnancy complication. This review also emphasizes the importance of following a healthy lifestyle for women with PCOS and of individualized care according to overall risk factors for pregnancy complications.

Maternal interventions to improve offspring outcomes in rodent models of diet-induced obesity: a review

Maternal obesity is an adverse factor that affects the intrauterine environment during critical periods of fetal developmental causing adverse lifelong effects on offspring health. Several different interventions have been performed in animal models of obesity to ameliorate maternal conditions and consequently reduce the adverse effects on offspring. Our aim was to critically review studies involving murine models of obesity induced by high fat diet (HFD), assessing maternal outcomes during pregnancy and the related offspring conditions. We carried out a computerized literature search of PubMed and Medline. We identified eight studies that fulfilled the inclusion criteria and have performed interventions in pregnancy with natural, synthetized compounds, and lifestyle modifications. Metabolic profile and lipid metabolism were improved by inositols, resveratrol, germinated brown rice (GBR), and exercise in the mother. The offspring whose mother received resveratrol, adiponectin, GBR, and exercise, showed an improvement in leptin, triglycerides, adiponectin levels, and a decrease in insulin resistance. These experimental studies demonstrate that several interventions in pregnant rodents improve the metabolic profile of both the mother and the offspring. Clinical research could now explore the efficacy and safety of such interventions, interrupting the vicious circle that an obese mother generates a child prone to develop metabolic (and cardiovascular) disease in adult life.

Myo-inositol lowers the risk of developing gestational diabetic mellitus in pregnancies: A systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

AIMS

to explore the potential benefit of myo-inositol on pregnant women with high risk of developing gestational diabetes mellitus (GDM).

METHODS

Pubmed, Embase, and Cochrane library were systematically searched for randomized controlled trials (RCTs) comparing myo-inositol with placebo for pregnant women with risk factors of GDM. Primary outcome were the incidence of GDM and birth weight. Secondary outcomes included fasting, 1h, and 2h oral glucose tolerance test (OGTT), and complications. Trial sequential analysis (TSA) was performed on primary outcomes to confirm the pooled results. Number needed to treat (NNT) was calculated to show the efficacy of myo-inositol supplement.

RESULTS

Four RCTs with 586 patients were included. Compared with placebo, patients with myo-inositol supplement had significantly lower the risk of developing GDM (RR=0.44, 95% CI [0.32, 0.62], P<0.0001) without heterogeneity (I²=0%, P=0.99), which was confirmed by TSA. NNT was 6.2 and rounded to 7. Myo-inositol did not significantly decrease birth weight (60.60g, 95% CI [-177.21, 56.02], P=0.31) with significant heterogeneity (I²=52%, P=0.12), but was not confirmed by TSA. Myo-inositol supplement was related to significantly lower fasting, 1h, and 2h OGTT value and the incidence of pre-term delivery. Difference was not significant between myo-inositol and placebo regarding incidence of other complications.

CONCLUSION

Myo-inositol is related to lower incidence of GDM, as well as fasting, 1h, and 2h OGTT value, in pregnant women with high risk of this condition. Myo-inositol might not be related to a lower birth weight, which needs further confirmation.

The efficacy of myo-inositol supplementation to prevent gestational diabetes onset: a meta-analysis of randomized controlled trials

INTRODUCTION

The efficacy of myo-inositol supplementation to prevent gestational diabetes onset remains controversial. We conducted a systematic review and meta-analysis to explore the influence of myo-inositol supplementation on the incidence of gestational diabetes.

METHODS

We search PubMed, Embase, Web of science, EBSCO, and Cochrane Library databases through November 2017 for randomized controlled trials (RCTs) assessing the effect of myo-inositol supplementation on gestational diabetes onset. This meta-analysis is performed using the random-effect model.

RESULTS

Five randomized controlled trials (RCTs) are included in the meta-analysis. Compared with control group in pregnant women, myo-inositol supplementation is associated with significantly reduced incidence of gestational diabetes (risk ratio (RR) = 0.43; 95%CI = 0.21-0.89; p = .02), and preterm delivery (RR = 0.36; 95%CI = 0.17-0.73; p = .005), but has no substantial impact on 2-h glucose oral glucose tolerance test (OGTT) (mean difference (MD) = -6.90; 95%CI = -15.07 to 1.27; p = .10), gestational age at birth (MD = 0.74; 95%CI = -1.06 to 2.54; p = .42), birth weight (MD = -5.50; 95%CI = -116.99 to 105.99; p = .92), and macrosomia (RR = 0.65; 95%CI = 0.20-2.11; p = .47).

CONCLUSIONS

Myo-inositol supplementation has some ability to reduce the incidence of gestational diabetes and preterm delivery in pregnant women.

Therapeutic approach for metabolic disorders and infertility in women with PCOS

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder affecting 5-10% of women of reproductive age. It generally shows with oligo/amenorrhea, anovulatory cycles, clinical o biochemical hirsutism, polycystic ovaries and, in a significant percentage of cases, insulin resistance. PCOS is defined as a multifactorial pathology, determined by the association of many factors: genetic, endocrine and environmental. The first and most effective treatment of PCOS is to change life-style and lose weight. The use of oral contraceptives has been shown effective in reducing acne and hirsutism and regulates the menstrual cycle. For women with severe hirsutism, the addition of antiandrogens to estrogen-progestin therapy has significantly improved the results. In cases of anovulatory infertility, the drug of first choice is clomiphene citrate, followed by low-dose gonadotropins. Recently, insulin-sensitizing drugs have been widely prescribed for PCOS patients. They are particularly effective in reducing insulin resistance and improving ovulatory performance. Besides insulin-sensitizing drugs, natural substances, such as inositol, seems to have good efficacy, similar to metformin with fewer side effects. New substances that could be used include statins and natural statins, such as monakolin, alone or combined with myo-inositol. These substances do not have side effects and greatly reduce the hyperandrogenic component in these patients.

Thermoanalytical study of sweetener myo-inositol: α and β polymorphs

This work investigates the thermal behavior of α and β myo-inositol polymorphs. The inositol is a natural compound widely used in the food industry due to its presence in carbohydrate metabolism and its sweet taste. The occurrence of polymorphism could change some physico-chemical properties, such as melting and sublimation temperatures, and solubility. Therefore, the thermal study of polymorphism is important to ensure better conditions for synthesis, storage, and transportation of food that contains the myo-inositol. Simultaneous Termogravimetry-Differential Thermal Analysis, Photovisual Differential Scanning Calorimetry, Polarized Light Thermomicroscopy, and Powder X-ray Diffraction were used in investigation. The data show a new thermal event associated to β myo-inositol melting at 221.43°C, suggesting that the solid-solid transition at 185.68°C was incomplete. The kinetics data made it possible to determine the transition lifetime of myo-inositol to occur 5% of solid-solid transition at 20°C and 37°C: 126 and 8years, respectively.

The Prevention of Gestational Diabetes Mellitus With Antenatal Oral Inositol Supplementation: A Randomized Controlled Trial

OBJECTIVE

This study investigated if inositol in a combination of myo-inositol and D-chiro-inositol would prevent gestational diabetes mellitus (GDM) in women with a family history of diabetes.

RESEARCH DESIGN AND METHODS

This was a randomized controlled trial that examined whether inositol from the first antenatal visit prevents GDM. The trial was carried out in a single-center tertiary referral center. Women with a family history of diabetes were enrolled at the first antenatal visit. They were randomized to the intervention group, which received a combination of 1,100 mg myo-inositol, 27.6 mg D-chiro-inositol, and 400 μg folic acid, or to the control group, which received 400 μg folic acid only. All women had an oral glucose tolerance test between 24 and 28 weeks' gestation. The primary end point was the incidence of GDM. Statistical analysis was carried out using SPSS Statistical Package version 20.

RESULTS

Two hundred forty women, 120 in each arm, were recruited between January 2014 and July 2015. There were no differences in characteristics between the groups. The incidence of GDM was 23.3% (n = 28) in the intervention group compared with 18.3% (n = 22) in the control group (P = 0.34). The mean fasting plasma glucose at the glucose tolerance test was 81 mg/dL in both groups.

CONCLUSIONS

Commencing an inositol combination in early pregnancy did not prevent GDM in women with a family history of diabetes. Further studies are required to examine whether inositol supplements at varying doses may prevent GDM.

Nutritional Intervention Preconception and During Pregnancy to Maintain Healthy Glucose Metabolism and Offspring Health ("NiPPeR"): study protocol for a randomised controlled trial

Background

Improved maternal nutrition and glycaemic control before and during pregnancy are thought to benefit the health of the mother, with consequent benefits for infant body composition and later obesity risk. Maternal insulin resistance and glycaemia around conception and in early pregnancy may be key determinants of maternal physiology and placental function, affecting fetal nutrient supply and maternal-feto-placental communications throughout gestation, with implications for later postnatal health.

Methods/design

This double-blind randomised controlled trial will recruit up to 1800 women, aged 18–38 years, who are planning a pregnancy in the United Kingdom (UK), Singapore and New Zealand, with a view to studying 600 pregnancies. The primary outcome is maternal glucose tolerance at 28 weeks’ gestation following an oral glucose tolerance test. Secondary outcomes include metabolic, molecular and health-related outcomes in the mother and offspring, notably infant body composition. Participants will be randomly allocated to receive a twice-daily control nutritional drink, enriched with standard micronutrients, or a twice-daily intervention nutritional drink enriched with additional micronutrients, myo-inositol and probiotics, both demonstrated previously to assist in maintaining healthy glucose metabolism during pregnancy. Myo-inositol is a nutrient that enhances cellular glucose uptake. The additional micronutrients seek to address deficiencies of some B-group vitamins and vitamin D that are both common during pregnancy and that have been associated with maternal dysglycaemia, epigenetic changes and greater offspring adiposity. Women who conceive within a year of starting the nutritional drinks will be followed through pregnancy and studied with their infants at six time points during the first year of life. Blood, urine/stool, hair and cheek swabs will be collected from the mothers for genetic, epigenetic, hormone, nutrient and metabolite measurements, and assessments of the mother’s body composition, anthropometry, health, diet and lifestyle will be made. Infants will also undergo hair, cheek swab, urine and stool sampling for similar biological measurements; infant body composition will be assessed and feeding recorded.

Discussion

There is an increasing focus on the need to optimise maternal nutrition starting prior to conception. This trial will provide evidence on the potential for nutritional interventions beginning prior to conception to promote healthy maternal and offspring outcomes.

Trial registration

ClinicalTrials.gov, identifier: NCT02509988, Universal Trial Number U1111-1171-8056. Registered on 16 July 2015. This is an academic-led study by the EpiGen Global Research Consortium.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1875-x) contains supplementary material, which is available to authorized users.

The effect of combined inositol supplementation on maternal metabolic profile in pregnancies complicated by metabolic syndrome and obesity

BACKGROUND

Myoinositol and D-chiroinositol improve insulin resistance in women with obesity and gestational diabetes and in postmenopausal women with metabolic syndrome. We previously reported that offspring born to hypertensive dams lacking endothelial nitric oxide synthase and fed a high-fat diet develop metabolic-like syndrome phenotype.

OBJECTIVE

The objective of the study was to investigate the effect of a mixture of myoinositol/D-chiroinositol supplementation during pregnancy on the maternal metabolic profile in pregnancies complicated by the metabolic-like syndrome and obesity using a pregnant mouse model.

STUDY DESIGN

Female heterozygous endothelial nitric oxide synthase(-/+) mice with moderate hypertension were placed on a high-fat diet for 4 weeks to induce a metabolic-like syndrome phenotype. Similarly, wild-type C57BL/6 mice were placed on a high-fat diet for 4 weeks to induce a murine obesity model. Mice were then bred with wild-type males. On gestational day 1, dams were randomly allocated to receive either a mixture of myoinositol/D-chiroinositol in water (7.2/0.18 mg/mL, respectively) or water as control (placebo). At term (gestational day 18), maternal weights, systolic blood pressure, and a glucose tolerance test were obtained. Dams were then killed; pups and placentas were weighed and maternal blood collected. Serum levels of metabolic biomarkers relevant to diabetes and obesity (ghrelin, gastric inhibitory peptide, glucagon-like peptide 1, glucagon, insulin, leptin, resistin) were measured by a multiplex enzyme-linked immunosorbent assay. Analysis was done comparing metabolic-like syndrome-myoinositol/D-chiroinositol-treated vs metabolic-like syndrome-nontreated mice and obese-myoinositol/D-chiroinositol-treated vs obese nontreated mice.

RESULTS

Mean systolic blood pressure was lower in metabolic-like syndrome pregnant mice treated with myoinositol/D-chiroinositol compared with placebo (P = .04), whereas there was no difference in systolic blood pressure between treated and placebo-treated obese pregnant mice. Pregnant metabolic-like syndrome mice treated with myoinositol/D-chiroinositol showed lower glucose values during the glucose tolerance test and in the area under the curve (myoinositol/D-chiroinositol: 17512.5 ± 3984.4 vs placebo: 29687.14 ± 8258.7; P = .003), but no differences were seen in the obese pregnant mice. Leptin serum levels were lower in the metabolic-like syndrome-myoinositol/D-chiroinositol-treated mice compared with the placebo group (myoinositol/D-chiroinositol: 16985 ± 976.4 pg/dL vs placebo: 24181.9 ± 3128.2 pg/dL, P = .045). No other differences were seen in any of the remaining serum metabolic biomarkers studied in metabolic-like syndrome and in obese pregnant mice. Maternal weight gain was not different in the pregnant metabolic-like syndrome dams, whereas it was lower in the obese myoinositol/D-chiroinositol-treated dams compared with the placebo group (myoinositol/D-chiroinositol: 10.9 ± 0.5 g vs 12.6 ± 0.6 g, P = .04). Fetal and placental weights did not differ between myoinositol/D-chiroinositol-treated and nontreated pregnant dams with metabolic-like syndrome and obesity.

CONCLUSION

Combined inositol treatment during pregnancy improves blood pressure, glucose levels at the glucose tolerance test, and leptin levels in pregnant dams with metabolic-like syndrome phenotype but not in obese pregnant dams. In addition, inositol treatment was associated with lower gestational weight gain in the obese but not in the metabolic-like syndrome pregnant dams.

Dietary supplementation with myo-inositol in women during pregnancy for treating gestational diabetes

BACKGROUND

Gestational diabetes mellitus (GDM) is any degree of glucose intolerance that first presents and is recognised during pregnancy and usually resolves after the birth of the baby. GDM is associated with increased short- and long-term morbidity for the mother and her baby. Treatment usually includes lifestyle modification and/or pharmacological therapy (oral antidiabetic agents or insulin) with the aim to maintain treatment targets for blood glucose concentrations. Finding novel treatment agents which are effective, acceptable and safe for the mother and her baby are important. One such emerging potential intervention is myo-inositol which is an isomer of inositol and occurs endogenously and is found in natural dietary sources such as fruits, vegetables, nuts and cereals.

OBJECTIVES

To assess if dietary supplementation with myo-inositol during pregnancy is safe and effective, for the mother and fetus, in treating gestational diabetes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2016), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (7 April 2016), and reference lists of retrieved studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials or cluster-randomised controlled trials reporting on the use of myo-inositol compared with placebo, no treatment or another intervention for the treatment of women with gestational diabetes. Quasi-randomised and cross-over studies are not eligible for inclusion. Women with pre-existing diabetes were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. For key outcomes (where data were available), we assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included two studies (142 women and infants), both were conducted in women in Italy and compared myo-inositol with a placebo control.None of the maternal primary outcomes pre-specified for this review were reported in the included studies: hypertensive disorders of pregnancy; caesarean section; development of subsequent type 2 diabetes mellitus. No data were reported for the majority of this review's maternal secondary outcomes. We could only perform meta-analysis for two secondary outcomes: fasting oral glucose tolerance test and additional pharmacological treatment. All other results are based on data from single studies. Overall, the risk of bias of the included studies was judged to be unclear due to lack of key methodological information.There was no evidence of a difference between treatment groups in need for additional pharmacotherapy or weight gain during pregnancy, although myo-inositol was associated with a lower body mass index (BMI) change (mean difference (MD) -1.50 kg/m2; 95% confidence interval (CI) -2.35 to -0.65; one trial, n = 73). Myo-inositol was associated with a reduction in the fasting blood glucose concentration at the end of treatment (MD -0.47 mmol/L; 95% CI -0.59 to -0.35; two trials, n = 142 women) compared with the control group. One small trial reported that myo-inositol was associated with a reduction in one-hour post-prandial blood glucose concentration at the end of treatment (MD -0.90 mmol/L; 95% CI -1.73 to -0.07; one trial, n = 73 women) compared with the control group. There was no difference between groups for the two-hour post-prandial blood glucose concentrations between groups (MD -0.70 mmol/L; 95% CI -1.46 to 0.06; one trial, n = 73 women). The one-hour and two-hour blood glucose concentrations show evidence of imprecision associated with wide CIs and small sample size.For the infant, there was no evidence of a difference in the risk for being born large-for-gestational age between the myo-inositol and the control group (risk ratio (RR) 0.36; 95% CI 0.02 to 8.58; one trial, n = 73 infants; low-quality evidence). The evidence was downgraded due to imprecision. This review's other primary outcomes were not reported in the included trials: perinatal mortality (stillbirth and neonatal mortality); mortality of morbidity composite (as defined by the trials); neurosensory disability. Infants in the myo-inositol group were less likely to have neonatal hypoglycaemia compared with the placebo group (RR 0.05; 95% CI 0.00 to 0.85; one study, n = 73 infants; low-quality evidence). There is evidence of imprecision for this outcome with low event rates and small sample size. There was no evidence of a difference between treatment and placebo groups for preterm birth or birthweight. Myo-inositol was associated with a later gestational age at birth compared with the placebo group (MD 2.10 weeks; 95% CI 1.27 to 2.93; one trial, n = 73 infants). No data were reported for any of the other neonatal outcomes for this review.No long-term outcomes were reported for the mother, infant as a child, infant as an adult, or health service outcomes.

AUTHORS' CONCLUSIONS

There are insufficient data to evaluate the effect of myo-inositol for the treatment of gestational diabetes, with no data to examine the majority of outcomes in this review. There do not appear to be any benefits for the infant associated with exposure to myo-inositol such as reduced risk of being born large-for-gestational age. Although the risk of neonatal hypoglycaemia is reduced for the myo-inositol group, there is evidence of imprecision. Evidence from two studies suggested that myo-inositol was associated with a reduced change in maternal BMI and fasting blood sugar concentration compared with placebo. There is a lack of reporting of the clinically meaningful outcomes pre-specified for this review.Uncertainty of the effectiveness of myo-inositol as a treatment for GDM for key maternal and infant outcomes remains and further high- quality trials with appropriate sample sizes are required to further investigate the role of myo-inositol as a treatment or co-treatment for women with gestational diabetes. Future trials should report on the core outcomes for GDM identified in the methods section of this review. Participants of varying ethnicities and with varying risk factors for GDM should be included in future trials. In addition, further trials of myo-inositol for the treatment of GDM should explore the optimal dose, frequency and timing of supplementation, report on adverse effects and assess the long- term effects of this intervention. Economic analysis or health service use and costs should also be included.

Inositol and human reproduction. From cellular metabolism to clinical use

Inositol is an organic compound of high biological importance that is widely distributed in nature. It belongs to the sugar family and is mainly represented by its two dominant stereoisomers: myo-inositol and D-chiro-inositol that are found in the organism in the physiological serum ratio 40:1. Inositol and its derivatives are important components of the structural phospholipids of the cell membranes and are precursors of the second messengers of many metabolic pathways. A high concentration of myoinositol is found in the follicular fluid and in semen. Inositol deficiency and the impairment of the inositol-dependent pathways may play an important role in the pathogenesis of insulin resistance and hypothyroidism. The results of the research also point out the potential beneficial role of inositol supplementation in polycystic ovarian syndrome and in the context of assisted reproduction technologies and in vitro fertilization. The main aim of the article is to overview the major inositol-dependent metabolic pathways and to discuss its importance for reproduction.

Inositol's and other nutraceuticals' synergistic actions counteract insulin resistance in polycystic ovarian syndrome and metabolic syndrome: state-of-the-art and future perspectives

The incidence of metabolic syndrome (MetS), type II diabetes (T2D) and polycystic ovarian syndrome (PCOS) has been progressively increasing. Insulin resistance (InsR) seems to play a key role in a majority of phenotypes of these conditions, altering metabolic homeostasis, within muscle, liver, adipose and other tissues. Hyperinsulinemia is often associated with InsR and causes hormonal imbalances especially within ovaries and adrenals. Inositol is a polyalcohol, naturally occurring as nine stereoisomers, including D-chiro-inositol (DCI) and myo-inositol (MI), which have prominent roles in the metabolism of glucose and free fatty acids. MI and DCI have been classified as insulin-sensitizers and seem to adequately counteract several InsR-related metabolic alterations with a safe nutraceutical profile. Based on our analysis of selected studies that investigated MI and/or DCI, we conclude that supplementation with MI and/or DCI complement each other in their metabolic actions and act in synergy with other insulin sensitizing drugs and/or nutraceuticals. Nevertheless, considering the possible severe bias due to different methodologies across published studies, we conclude that there is a need for further studies on larger cohorts and with greater statistical power. These should further clarify outcomes and suitable therapeutic dosages of MI and DCI, possibly based on each patient's clinical status.

Myo-Inositol Safety in Pregnancy: From Preimplantation Development to Newborn Animals

Myo-inositol (myo-Ins) has a physiological role in mammalian gametogenesis and embryonic development and a positive clinical impact on human medically assisted reproduction. We have previously shown that mouse embryo exposure to myo-Ins through preimplantation development in vitro increases proliferation activity and blastocyst production, representing an improvement in culture conditions. We have herein investigated biochemical mechanisms elicited by myo-Ins in preimplantation embryos and evaluated myo-Ins effects on postimplantation/postnatal development. To this end naturally fertilized embryos were cultured in vitro to blastocyst in the presence or absence of myo-Ins and analyzed for activation of the PKB/Akt pathway, known to modulate proliferation/survival cellular processes. In parallel, blastocyst-stage embryos were transferred into pseudopregnant females and allowed to develop to term and until weaning. Results obtained provide evidence that myo-Ins induces cellular pathways involving Akt and show that (a) exposure of preimplantation embryos to myo-Ins increases the number of blastocysts available for uterine transfer and of delivered animals and (b) the developmental patterns of mice obtained from embryos cultured in the presence or absence of myo-Ins, up to three weeks of age, overlap. These data further identify myo-Ins as a possibly important supplement for human preimplantation embryo culture in assisted reproduction technology.

Antenatal dietary supplementation with myo-inositol in women during pregnancy for preventing gestational diabetes

BACKGROUND

Gestational diabetes, glucose intolerance with onset or first recognition during pregnancy, is a rising problem worldwide. Both non-pharmacological and pharmacological approaches to the prevention of gestational diabetes have been, and continue to be explored. Myo-inositol, an isomer of inositol, is a naturally occurring sugar commonly found in cereals, corn, legumes and meat. It is one of the intracellular mediators of the insulin signal and correlated with insulin sensitivity in type 2 diabetes. The potential beneficial effect on improving insulin sensitivity suggests that myo-inositol may be useful for women in preventing gestational diabetes.

OBJECTIVES

To assess if antenatal dietary supplementation with myo-inositol is safe and effective, for the mother and fetus, in preventing gestational diabetes.

SEARCH METHODS

We searched the Pregnancy and Childbirth Group's Trials Register, ClinicalTrials.gov, WHO ICTRP (2 November 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

We sought published and unpublished randomised controlled trials, including conference abstracts, assessing the effects of myo-inositol for the prevention of gestational diabetes mellitus (GDM). Quasi-randomised and cross-over trials were not eligible for inclusion, but cluster designs were eligible. Participants in the trials were pregnant women. Women with pre-existing type 1 or type 2 diabetes were excluded. Trials that compared the administration of any dose of myo-inositol, alone or in a combination preparation were eligible for inclusion. Trials that used no treatment, placebo or another intervention as the comparator were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, risk of bias and extracted the data. Data were checked for accuracy.

MAIN RESULTS

We included four randomised controlled trials (all conducted in Italy) reporting on 567 women who were less than 11 weeks' to 24 weeks' pregnant at the start of the trials. The trials had small sample sizes and one trial only reported an interim analysis. Two trials were open-label. The overall risk of bias was unclear.For the mother, supplementation with myo-inositol was associated with a reduction in the incidence of gestational diabetes compared with control (risk ratio (RR) 0.43, 95% confidence interval (CI) 0.29 to 0.64; three trials; n = 502 women). Using GRADE methods this evidence was assessed as low with downgrading due to unclear risk of bias for allocation concealment in two of the included trials and lack of generalisability of findings. For women who received myo-inositol supplementation, the incidence of GDM ranged from 8% to 18%; for women in the control group, the incidence of GDM was 28%, using International Association of Diabetes and Pregnancy Study Groups Consensus Panel 2010 criteria to diagnose GDM.Two trials reported on hypertensive disorders of pregnancy, a primary maternal outcome of this review. There was no clear difference in risk of hypertensive disorders of pregnancy between the myo-inositol and control groups (average RR 0.43, 95% CI 0.02 to 8.41; two trials; n = 398 women; Tau(2) = 3.23; I(2) = 69%). Using GRADE methods, this evidence was assessed as very low, with downgrading due to wide confidence intervals with very low event rates, a small sample size, and lack of blinding and unclear allocation concealment methods, and a lack of generalisability. For women who received myo-inositol the risk of hypertensive disorders of pregnancy ranged from 0% to 33%; for women in the control group the risk was 4%.For the infant, none of the included trials reported on the primary neonatal outcomes of this systematic review (large-for-gestational age, perinatal mortality, mortality or morbidity composite).In terms of this review's secondary outcomes, there was no clear difference in the risk of caesarean section between the myo-inositol and control groups (RR 0.95, 95% CI 0.76 to 1.19; two trials; n = 398 women). Using GRADE methods, this evidence was assessed as low, with downgrading due to unclear risk of bias in one trial and lack of generalisability. For women who received myo-inositol supplementation, the risk of having a caesarean section ranged from 34% to 54%; for women in the control group the was 45%. There were no maternal adverse effects of therapy in the two trials that reported on this outcome (the other two trials did not report this outcome).Two trials found no clear difference in the risk of macrosomia between infants whose mothers received myo-inositol supplementation compared with controls (average RR 0.35, 95% CI 0.02 to 6.37; two trials; n = 398 infants;Tau(2) = 3.33; I(2) = 73%). Similarly, there was no clear difference between groups in terms of neonatal hypoglycaemia (RR 0.36, 95% CI 0.01 to 8.66) or shoulder dystocia (average RR 2.33, 95% CI 0.12 to 44.30, Tau(2) = 3.24; I(2) = 72%).There was a lack of data available for a large number of maternal and neonatal secondary outcomes, and no data for any of the long-term childhood or adulthood outcomes, or for health service cost outcomes.

AUTHORS' CONCLUSIONS

Evidence from four trials of antenatal dietary supplementation with myo-inositol during pregnancy shows a potential benefit for reducing the incidence of gestational diabetes. No data were reported for any of this review's primary neonatal outcomes. There were very little outcome data for the majority of this review's secondary outcomes. There is no clear evidence of a difference for macrosomia when compared with control.The current evidence is based on small trials that are not powered to detect differences in outcomes including perinatal mortality and serious infant morbidity. All of the included studies were conducted in Italy which raises concerns about the lack of generalisability of the evidence to other settings. There is evidence of inconsistency and indirectness and as a result, many of the judgements on the quality of the evidence were downgraded to low or very low quality (GRADEpro Guideline Development Tool).Further trials for this promising antenatal intervention for preventing gestational diabetes are encouraged and should include pregnant women of different ethnicities and varying risk factors and use of myo-inositol (different doses, frequency and timing of administration) in comparison with placebo, diet and exercise or pharmacological interventions. Outcomes should include potential harms including adverse effects.

Relationship Between Myo-Inositol Supplementary and Gestational Diabetes Mellitus: A Meta-Analysis

To determine whether myo-inositol supplement will increase the action of endogenous insulin, which is mainly measured by markers of insulin resistance such as homeostasis model assessment of insulin resistance.PubMed, Cochrane Library, Embase, and web of science were comprehensively searched using "gestational diabetes mellitus" and "myo-inositol" to identify relevant studies. Both subject headings and free texts were adopted. The methodological quality of the included studies were assessed and pooled analyzed by the methods recommended by the Cochrane collaboration.A total of 5 trials containing 513 participants were included. There was a significant reduction in aspects of gestational diabetes incidence (risk ratio [RR], 0.29; 95% confidence interval (95% CI), 0.19-0.44), birth weight (mean difference [MD], -116.98; 95% CI, -208.87 to -25.09), fasting glucose oral glucose tolerance test (OGTT) (MD, -0.36; 95% CI, -0.51 to -0.21), 1-h glucose OGTT (MD, -0.63; 95% CI, -1.01 to -0.26), 2-h glucose OGTT (MD, -0.45; 95% CI, -0.75 to -0.16), and related complications (odds ratio [OR], 0.28; 95% CI 0.14-0.58).On the basis of current evidence, myo-inositol supplementation reduces the development of gestational diabetes mellitus (GDM), although this conclusion requires further evaluation in large-scale, multicenter, blinded randomized controlled trials.