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

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

Patient empowerment and the Mediterranean diet as a possible tool to tackle prediabetes associated with overweight or obesity: a pilot study

AIM

The objective of this study was to investigate the effect of implementation of short-term patient empowerment as applied to Mediterranean diet (MD) adherence on metabolic and anthropometric parameters in prediabetic overweight or obese subjects.

METHODS

The sample included 42 subjects with prediabetes, aged 18-75 years and with body mass index (BMI) > 25 kg/m², who received dietary advice on MD by nutritionists during session groups every 2 weeks for 4 months. Data on energy caloric intake and macronutrient consumption were collected using a 7-day food diary record. Adherence to MD was investigated through the PREvención con DIeta MEDiterránea (PREDIMED) questionnaire. No advice was given regarding caloric restriction and physical activity. At baseline and at the end of the study, each subject underwent anthropometric, metabolic, and nutritional assessments.

RESULTS

Approximately 40.5% of subjects had achieved restoration of normal glucose tolerance by the end of the study. Fasting plasma glucose, glycated hemoglobin (HbA1C), BMI, waist circumference, blood pressure, visceral adiposity index, triglycerides, and total and LDL cholesterol levels were significantly decreased, while HDL cholesterol had significantly increased by the end of the study. The subjects significantly increased adherence to MD, as assessed by the PREDIMED questionnaire at follow-up. A reduction of prevalence of the metabolic syndrome was also reported. Interestingly, the PREDIMED score correlated with HbA1C values at follow-up, after adjusting for BMI and total caloric intake.

CONCLUSIONS

Implementation of short-term patient empowerment as applied to MD adherence was shown to improve anthropometric and metabolic parameters in prediabetic overweight or obese subjects. This is of considerable importance, given that diet must be the cornerstone of treatment in patients at high risk of developing type 2 diabetes.

Water intake keeps type 2 diabetes away? Focus on copeptin

INTRODUCTION

In both diabetic subjects and animal models high levels of vasopressin (AVP) have beendetected. The relationship between AVP and glucose metabolism is mediated through several direct andindirect effects and most of them are still unknown.

METHODS

We have reviewed 100 manuscripts retrieved from Cochrane Library, Embase and Pubmeddatabases in order to highlight a possible relationship between copeptin and type 2 diabetes and to provideinsights on the molecular mechanism that could explain this association.

RESULTS AND CONCLUSIONS

AVP potentiates CRH action at pituitary level resulting in an increased ACTH secretion and in turn in an increased cortisol secretion that escapes the negative feedback loop. Further, AVP regulates insulin and glucagon secretion through V1b receptor and promotes hepatic glycogenolysis and gluconeogenesis through V1a receptor. In addition to worsen glucose metabolism, AVP has been reported to have a role in the pathogenesis of diabetic complications such as cardiovascular diseases, kidney and ocular complications. Due to the very low concentration of AVP in the blood, the small size and poor stability, the assay of AVP is very difficult to perform. Thus, copeptin, the stable C-terminal portion of the prepro-vasopressin peptide has been identified as an easier assay to be measured and that mirrors AVP activity. Although there are promising evidence that copeptin could be involved in the pathogenesis of type 2 diabetes, further studies need to demonstrate the importance of copeptin as clinical marker to predict glucose metabolism derangements.

First Results from CUORE: A Search for Lepton Number Violation via 0νββ Decay of ^{130}Te

The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-number-violating process: ^{130}Te neutrinoless double-beta decay. Examining a total TeO_{2} exposure of 86.3 kg yr, characterized by an effective energy resolution of (7.7±0.5)  keV FWHM and a background in the region of interest of (0.014±0.002)  counts/(keV kg yr), we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T_{1/2}^{0ν}(^{130}Te)>1.3×10^{25}  yr (90% C.L.); the median statistical sensitivity of this search is 7.0×10^{24}  yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T_{1/2}^{0ν}(^{130}Te)>1.5×10^{25}  yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find m_{ββ}<(110-520)  meV, where the range reflects the nuclear matrix element estimates employed.

Vitamin D and pancreas: The role of sunshine vitamin in the pathogenesis of diabetes mellitus and pancreatic cancer

Increasing evidence suggests that vitamin D exerts multiple effects beyond bone and calcium metabolism. Vitamin D seems to play a role in pancreatic disease, including type 1 and type 2 diabetes mellitus as well as pancreatic cancer. Vitamin D's immune-modulatory action suggests that it could help prevent type 1 diabetes. In type 2 diabetes, vitamin D may influence β-cell function, insulin sensitivity, and systematic inflammation-all characteristic pathways of that disease. Data from observational studies correlated vitamin D deficiency with risk of type 1 and type 2 diabetes. Prospective and ecological studies of pancreatic cancer incidence generally support a beneficial effect of higher 25-hydroxyvitamin D concentration as well as inverse correlations between UVB dose or exposure and incidence and/or mortality rate of pancreatic cancer. This review discusses the literature regarding vitamin D's role in risk of diabetes and pancreatic cancer. The results to date generally satisfy Hill's criteria for causality regarding vitamin D and incidence of these pancreatic diseases. However, large randomized, blinded, prospective studies are required to more fully evaluate the potential therapeutic role of vitamin D in preventing pancreatic diseases.

Current Insights Into Inositol Isoforms, Mediterranean and Ketogenic Diets for Polycystic Ovary Syndrome: From Bench to Bedside

BACKGROUND

Polycystic ovary syndrome (PCOS) is a complex syndrome characterized by reproductive and metabolic implications. Lifestyle changes, such as diet and exercise, are considered first-line treatment for women affected by PCOS. Pharmacologic treatments target the hormonal and metabolic dysregulations associated to the disease such as insulin resistance, anovulation, hirsutism and menstrual irregularities.

OBJECTIVE

To focus on the role of inositol isoforms, as well as Mediterranean and ketogenic diets, as possible therapeutic strategies in PCOS women.

METHOD

Narrative overview, synthesizing the findings of literature retrieved from searches of computerized databases.

RESULTS

Accumulating evidence suggests that two inositol isoforms, myo- and D-chiro-, may play a pivotal role in re-addressing both hormonal and metabolic parameters toward homeostasis, counteracting the symptoms and signs typical of this syndrome. In addition, studies focused on Mediterranean and ketogenic diet provided positive results in patients affected by obesity and type 2 diabetes, so these dietetic regimens could represent a fascinating dietetic treatment for the management of PCOS.

CONCLUSION

Both the isoforms of inositol are effective in improving ovarian function and metabolism in patients with PCOS. In spite of accumulating evidence, it is currently not possible to draw firm conclusion(s) about the efficacy of these interventions considering the severe bias due to different samples size, dose, and duration of intervention among the published studies on this topic. Furthermore, future longitudinal cohort studies along with prospective interventional trials may contribute to better clarify the role of Mediterranean and ketogenic diets in the treatment of PCOS.

Current evidence on vitamin D deficiency and kidney transplant: What's new?

Kidney transplant is the treatment of choice for end-stage chronic kidney disease. Kidneys generate 1,25-dihydroxyvitamin D (calcitriol) from 25-hydroxyvitamin D (calcidiol) for circulation in the blood to regulate calcium levels. Transplant patients with low calcidiol levels have an increased risk of metabolic and endocrine problems, cardiovascular disease, type 2 diabetes mellitus, poor graft survival, bone disorders, cancer, and mortality rate. The recommended calcidiol level after transplant is at least 30 ng/mL (75 nmol/L), which could require 1000-3000 IU/d vitamin D3 to achieve. Vitamin D3 supplementation studies have found improved endothelial function and acute rejection episodes. However, since kidney function may still be impaired, raising calcidiol levels may not lead to normal calcitriol levels. Thus, supplementation with calcitriol or an analog, alfacalcidiol, is often employed. Some beneficial effects found include possible improved bone health and reduced risk of chronic allograft nephropathy and cancer.

Shedding new light on female fertility: The role of vitamin D

In the last decades several studies suggested that vitamin D is involved in the modulation of the reproductive process in women due to the expression of VDR and 1α-hydroxylase in reproductive tissues such as ovary, uterus, placenta, pituitary and hypothalamus. Vitamin D has also a role in the regulation of sex hormone steroidogenesis. Increasing evidence suggests that vitamin D might have a regulatory role in polycystic ovary syndrome (PCOS)-associated symptoms, including ovulatory dysfunction, insulin resistance and hyperandrogenism. Vitamin D deficiency also has been reported to contribute to the pathogenesis of endometriosis due to its immunomodulatory and anti-inflammatory properties. Although most of the studies supported a role of vitamin D in the onset of these diseases, randomized controlled trials to assess the efficacy of vitamin D supplementation have never been performed. In this review we critically discuss the role of vitamin D in female fertility, starting from in vitro and in vivo studies, focusing our attention on the two most frequent causes of female infertility: PCOS and endometriosis.

Gut: A key player in the pathogenesis of type 2 diabetes?

The gut regulates glucose and energy homeostasis; thus, the presence of ingested nutrients into the gut activates sensing mechanisms that affect both glucose homeostasis and regulate food intake. Increasing evidence suggest that gut may also play a key role in the pathogenesis of type 2 diabetes which may be related to both the intestinal microbiological profile and patterns of gut hormones secretion. Intestinal microbiota includes trillions of microorganisms but its composition and function may be adversely affected in type 2 diabetes. The intestinal microbiota may be responsible of the secretion of molecules that may impair insulin secretion/action. At the same time, intestinal milieu regulates the secretion of hormones such as GLP-1, GIP, ghrelin, gastrin, somatostatin, CCK, serotonin, peptide YY, GLP-2, all of which importantly influence metabolism in general and in particular glucose metabolism. Thus, the aim of this paper is to review the current evidence on the role of the gut in the pathogenesis of type 2 diabetes, taking into account both hormonal and microbiological aspects.

Adrenal Mass: Insight Into Pathogenesis and a Common Link With Insulin Resistance

Adrenal mass (AM) is a common incidental finding detected during radiological investigations with an estimated incidence of 4%. Subjects with AM do not show any physical signs of adrenal hormonal excess, although they are often insulin resistant. Interestingly, apparently nonfunctioning AMs are often associated with a high prevalence of insulin resistance (IR) and metabolic syndrome. However, it is unclear whether AM develops from a primary IR and compensatory hyperinsulinemia or whether IR is only secondary to the slight cortisol hypersecretion by AM. Further, the degree of IR has been directly reported to correlate to the size of AM, thus allowing one to hypothesize that compensatory hyperinsulinemia to IR could be mitogenic on the adrenal cortex acting through the activation of insulin and insulinlike growth factor 1 receptors. Thus, the aim of the present article is to review the current evidence on the link between AM and compensatory hyperinsulinemia to IR.

Low vitamin D status and obesity: Role of nutritionist

Low vitamin D status and obesity have concomitantly reached epidemic levels worldwide. Up to now the direction of the association between low vitamin D status and obesity, the exact mechanisms responsible for this association and the clinical usefulness to increase vitamin D status for reducing adiposity still warrant further evaluation. The aim of the present review was to examine the current evidence linking low vitamin D status and obesity in relation to the role of the nutritionist. On the one side, considering obesity as a causal factor, low sun exposure in obese individuals due to their sedentary lifestyle and less outdoor activity, vitamin D sequestration in adipose tissue, and volumetric dilution of ingested or cutaneously synthesized vitamin D₃ in the large fat mass of obese patients, might represent some of the factors playing a major role in the pathogenesis of the low vitamin D status. On the other side, the expression of both vitamin D₃ receptors and enzymes responsible for vitamin D₃ metabolism in adipocytes depicted a role for the low vitamin D status per se in the development of obesity by modulating adipocyte differentiation and lipid metabolism. Nutritionists need to accurately address the aspects influencing the low vitamin D status in obesity and the vitamin D supplementation in obese individuals.

Low serum vitamin D-status, air pollution and obesity: A dangerous liaison

The aim of this review is to provide a general overview of the possible associations among the vitamin D status, air pollution and obesity. Sunlight exposure accounts in humans for more than 90 % of the production of vitamin D. Among emerging factors influencing sunlight-induced synthesis of vitamin D, prospective and observational studies proved that air pollution constitutes an independent risk factor in the pathogenesis of vitamin D hypovitaminosis. In addition, environmental pollutants can affect risk of obesity when inhaled, in combination with unhealthy diet and lifestyle. In turn, obesity is closely associated with a low vitamin D status and many possible mechanisms have been proposed to explain this association. The associations of air pollution with low vitamin D status on the hand and with obesity on the other hand, could provide a rationale for considering obesity as a further link between air pollution and low vitamin D status. In this respect, a vicious cycle could operate among low vitamin D status, air pollution, and obesity, with additive detrimental effects on cardio-metabolic risk in obese individuals. Besides vitamin D supplementation, nutrient combination, used to maximize the protective effects against air pollution, might also contribute to improve the vitamin D status by attenuating the "obesogen" effects of air pollution.

Lifestyle changes in the management of adulthood and childhood obesity

Adulthood and childhood obesity is rapidly becoming an epidemic problem and it has a short and long-term impact on health. Short-term consequences are mostly represented by psychological effects; in fact obese children have more chances to develop psychological or psychiatric problems than non-obese children. The main long-term effect is represented by the fact that childhood obesity continues into adulthood obesity and this results in negative effects in young adult life, since obesity increases the risk to develop morbidity and premature mortality. The obesity-related diseases are mostly represented by hypertension, type 2 diabetes, dyslipidemia, cardiovascular diseases. Medical treatment should be discouraged in childhood because of the side effects and it should be only reserved for obese children with related medical complications. Lifestyle changes should be encouraged in both adulthood and childhood obesity. This review focuses on the management of obesity both in adulthood and in childhood, paying particular attention to lifestyle changes that should be recommended.

Reproductive issues in patients undergoing Hematopoietic Stem Cell Transplantation: an update

In 1963 George Mathé announced to the world that he had cured a patient of leukaemia by means of a bone-marrow transplant. Since than much progress has been made and nowadays Hematopoietic Stem Cell Transplantation (HSCT) is considered the most effective treatment of numerous severe haematological diseases. Gynaecological complications in HSCT women represent a serious concern for these patients, but often underestimated by clinicians in the view of Overall Survival. The main gynaecological complications of HSCT are represented by: premature ovarian failure (POF), thrombocytopenia-associated menorrhagia, genital symptoms or sexual problems in course of chronic GVHD (cGVHD), osteoporosis, secondary solid tumours due to immunosuppressive drugs to treat cGVHD and severity of cGVHD, and fertility and pregnancy issues. In particular fertility-related issues are always more relevant for patients, whose life expectation is constantly growing up after HSCT.

Thus, taking care of a patient undergoing HSCT should primarily include gynaecological evaluation, even before conditioning regimen or chemotherapy for the underlying malignancy, as, in our opinion, it is of great importance to ensure a complete diagnostic work-up and intervention options to guarantee maximum reproductive health and a better quality of life in HSCT women.

The present review aims at describing principal features of the aforementioned gynaecological complications of HSCT, and to define, on the basis of current international literature, a specific protocol for the prevention, diagnosis, management and follow-up of gynaecological complications of both autologous and heterologous transplantation, before and after the procedure.

Oral contraceptives versus physical exercise on cardiovascular and metabolic risk factors in women with polycystic ovary syndrome: a randomized controlled trial

BACKGROUND

Although oral contraceptives (OCs) are one the most widespread therapy in young polycystic ovary syndrome (PCOS) women and physical exercise represents a crucial first step in the treatment of overweight and obese PCOS, no studies were performed to compare the effects on cardiovascular risk (CVR) of OCs and physical exercise in PCOS.

OBJECTIVE

To compare the effects of OCs administration and physical exercise on the CVR, clinical, hormonal and metabolic parameters in PCOS women.

METHODS

One hundred and fifty PCOS women were enrolled and were randomized to OCs (3 mg drospirenone plus 30 μg ethinyloestradiol), structured exercise training programme (SETP) or polyvitamin tablets. The intervention phase study was of 6 months. Primary outcome was intima-media thickness (IMT) and flow-mediated dilation (FMD). Secondary outcomes were clinical, hormonal and metabolic changes.

RESULTS

A significant reduction of IMT and a significant increase of FMD were observed in the SETP group after treatment. Compared to baseline, in the SETP group, a significant improvement in anthropometric measures, insulin sensitivity indexes, lipid profile, cardiopulmonary function, inflammatory markers and frequency of menses was observed. Oral contraceptives use was associated with a significant decrease of hyperandrogenism and a significant improvement of frequency of menses. Further, OCs use had a neutral effect on CVR risk factors.

CONCLUSION

OCs effectively treat hyperandrogenism and menstrual disturbances, while SETP is more effective in improving cardiometabolic profile and cardiopulmonary function in PCOS_.

Low 25 (OH) vitamin D levels are associated with autoimmune thyroid disease in polycystic ovary syndrome

Low 25(OH) vitamin D levels have been associated with several autoimmune diseases and recently with autoimmune thyroid disease (AITD). The aim of the study was to investigate the association of AITD with 25(OH) vitamin D levels in women with polycystic ovary syndrome (PCOS). Fifty women with PCOS were consecutively enrolled and underwent routine health checkups, which included measurements of 25(OH) vitamin D, anti-thyroid peroxidase (TPO-Ab), anti-thyreoglobulin (TG-Ab) antibodies, FT3, FT4, and TSH. Selecting 50 nmol/L as cut-off point, low 25(OH) vitamin D levels were detected in 23 of 50 patients (46 %). AITD was diagnosed when TPO-Ab levels exceeding 80 U/ml and/or TG-Ab levels exceeding 70 U/ml. AITD was detected in 12 of 50 patients (24 %). The levels of 25(OH) vitamin D were significantly lower in women with PCOS and AITD when compared with women with PCOS and without AITD (p = 0.02). In women with AITD no correlation was found between 25(OH) vitamin D and TG-Ab (r = 0.48; p = 0.16), TPO-Ab (r = 0.43; p = 0.21), TSH (r = 0.38; p = 0.27), FT3 (r = -0.40; p = 0.25) and FT4 levels (r = -0.54; p = 0.10). These findings suggest that low levels of 25(OH) vitamin D were significantly associated with AITD in women with PCOS.

Endocrine Aspects of Environmental "Obesogen" Pollutants

Growing evidence suggests the causal link between the endocrine-disrupting chemicals (EDCs) and the global obesity epidemics, in the context in the so-called “obesogenic environment”. Dietary intake of contaminated foods and water, especially in association with unhealthy eating pattern, and inhalation of airborne pollutants represent the major sources of human exposure to EDCs. This is of particular concern in view of the potential impact of obesity on chronic non-transmissible diseases, such as type 2 diabetes, cardiovascular disease, and hormone-sensitive cancers. The key concept is the identification of adipose tissue not only as a preferential site of storage of EDCs, but also as an endocrine organ and, as such, susceptible to endocrine disruption. The timing of exposure to EDCs is critical to the outcome of that exposure, with early lifetime exposures (e.g., fetal or early postnatal) particularly detrimental because of their permanent effects on obesity later in life. Despite that the mechanisms operating in EDCs effects might vary enormously, this minireview is aimed to provide a general overview on the possible association between the pandemics of obesity and EDCs, briefly describing the endocrine mechanisms linking EDCs exposure and latent onset of obesity.

Vitamin D and chronic diseases: the current state of the art

The objective was to provide the current state of the art regarding the role of vitamin D in chronic diseases (osteoporosis, cancer, cardiovascular diseases, dementia, autism, type 1 and type 2 diabetes mellitus, male and female fertility). The document was drawn up by panelists that provided their contribution according to their own scientific expertise. Each scientific expert supplied a first draft manuscript on a specific aspect of the document's topic that was subjected to voting by all experts as "yes" (agreement with the content and/or wording) or "no" (disagreement). The adopted rule was that statements supported by ≥75 % of votes would be immediately accepted, while those with <25 % would be rejected outright. Others would be subjected to further discussion and subsequent voting, where ≥67 % support or, in an eventual third round, a majority of ≥50 % would be needed. This document finds that the current evidence support a role for vitamin D in bone health but not in other health conditions. However, subjects with vitamin D deficiency have been found to be at high risk of developing chronic diseases. Therefore, although at the present time there is not sufficient evidence to recommend vitamin D supplementation as treatment of chronic diseases, the treatment of vitamin D deficiency should be desiderable in order to reduce the risk of developing chronic diseases.

First array of enriched Zn[Formula: see text]Se bolometers to search for double beta decay

The R&D activity performed during the last years proved the potential of ZnSe scintillating bolometers to the search for neutrino-less double beta decay, motivating the realization of the first large-mass experiment based on this technology: CUPID-0. The isotopic enrichment in [Formula: see text]Se, the Zn[Formula: see text]Se crystals growth, as well as the light detectors production have been accomplished, and the experiment is now in construction at Laboratori Nazionali del Gran Sasso (Italy). In this paper we present the results obtained testing the first three Zn[Formula: see text]Se crystals operated as scintillating bolometers, and we prove that their performance in terms of energy resolution, background rejection capability and intrinsic radio-purity complies with the requirements of CUPID-0.

Hypovitaminosis D: a novel risk factor for coronary heart disease in type 2 diabetes?

Vitamin D (25(OH)D) levels have been associated with cardiovascular disease. Thus, the aim of our study was to investigate the association of 25(OH)D levels with coronary heart disease (CHD) in 698 consecutive type 2 diabetic outpatients. 698 consecutive type 2 diabetic outpatients (25.2 % men, age 66 ± 9 years) and 100 (90 % men, age 65 ± 13 years) age-matched non-diabetic volunteers were enrolled. 25(OH)D assay and the main cardiovascular risk factors were explored. 25(OH)D concentration was 22 ± 10 ng/ml in control subjects and 18.23 ± 10 ng/ml in diabetic patients (p < 0.01). The prevalence of hypovitaminosis D was higher in diabetic patients than in control subjects (90 vs. 83 %, p < 0.01). Diabetic subjects with hypovitaminosis D had higher prevalence of high values of A1C (p < 0.01), BMI (p < 0.01), LDL cholesterol (p < 0.01), triglycerides (p < 0.01), and glycemia (p < 0.01) than their vitamin D-sufficient counterparts. 25(OH)D and HDL cholesterol were lower (p < 0.01), while BMI (p < 0.01), age (p < 0.01), systolic (p < 0.01) and diastolic blood pressure (p < 0.01), diabetes duration (p < 0.01), A1C (p < 0.01), glycemia (p < 0.01), fibrinogen (p < 0.01), triglycerides (p < 0.01), and total (p < 0.01) and LDL cholesterol (p < 0.01) were higher in diabetic subjects with CHD than diabetic subjects without CHD. At the logistic regression analysis, the association of vitamin D with CHD was lost, while sex (p = 0.026), diabetes duration (p = 0.023), and age (p = 0.024) were the most powerful predictors of CHD. The current study demonstrates that 25(OH)D does not have a direct effect on CHD but may have an indirect effect mediated by cardiovascular risk factors such as diabetes duration, age, and sex.

Inositols in the Treatment of Insulin-Mediated Diseases

A growing body of research is currently focused on the role of inositol isomers and in particular myo-inositol (MYO-INS) and D-chiroinositol (DCI) in the treatment of insulin resistance states. Both isomers have been shown to exert insulin-mimetic action and to lower postprandial glucose. Further, insulin resistance-related diseases were associated to derangements in inositol metabolism. Thus, the aim of this review is to provide current evidence on the potential benefits of inositol isomers (MYO-INS and DCI) in the treatment of disease associated to insulin resistance such as polycystic ovary syndrome (PCOS), gestational diabetes, and metabolic syndrome. Finally, molecular insights into inositol insulin-sensitizing effects will be covered focusing on the possible role of inositol glycans as insulin second messengers.