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This study investigates the effects of inositol (INO) supplementation on cardiac changes caused by Li in mice. The study involved 4 groups of C57BL6 mice (n=10 each): (i) mice orally administered with Li2CO3 for 8 weeks, then 4 additional weeks without (Li_group) or (ii) with INO supplementation (Li_INOdelayed_group) (total of 12 weeks); (iii) mice given Li2CO3 and INO supplementation concurrently for 12 weeks (Li+INO_group); (iv) one group left untreated (C–group). The INO was administered as a mixture of myo-inositol and d-chiro-inositol (80:1) in drinking water. The mice were characterised for heart morphology, function, electrical activity, arrhythmogenic susceptibility, and multiorgan histopathology (heart, liver and kidney). Cardiomyocyte size, protein expression of key signalling pathways related to hypertrophy, and transcription levels of ion channel subunits and hypertrophy markers were evaluated in the ventricle tissue. The study found that INO supplementation reduced the Li-induced cardiac adverse effects, including systolic impairment and increased susceptibility to arrhythmias. The positive effect on arrhythmias might be attributed to the restored expression levels of the potassium channel subunit Kv 1.5. Additionally, INO improved cardiomyocyte hypertrophy, possibly by inhibiting the Li-induced activation of the ERK1/2 signalling pathway and by restoring the normal expression level of BNP, and alleviated injury in the liver and kidney. The effect was preventive if INO supplementation was taken concurrently with Li and therapeutic if INO was administered after Li-induced cardiac impairments were established. These results provide new insights into the cardioprotective effect of INO and suggest a potential treatment approach for Li-induced cardiac disease.

Introduction and purpose Polycystic ovary syndrome is a common reproductive disorder, accompanied primarily by hyperandrogenism and insulin resistance. Myo-inositol (MI) and D-chiro-inositol (DCI), have emerged as potential therapeutic agents due to their role as insulin sensitizers. This article examines the effects of inositol therapy on fertility in women with PCOS and its role in assisted reproductive technology (ART). Studies suggest that inositols alleviate irregular menstruation, reduce androgen levels and positively affect ovulation rates. MI supplementation has also shown positive effects during controlled ovarian hyperstimulation and IVF procedures, reducing the required FSH dose and cycle length. However, despite positive results on ovulation and menstrual regularity, the article indicates the need for further studies to establish inositol as standard ART therapy in patients with PCOS. Material and methods The following review was based on articles from the PubMed and Google Scholar databases. Key search terms included polycystic ovary syndrome; assisted reproductive treatment, insulin resistance, inositols, Myo-inositol, D-chiro-inositol. Conclusions Inositols are a promising therapeutic option for women with PCOS. They have been shown to have positive effects on improving insulin sensitivity and fertility. However, despite inositol's safety and easy availability, the ideal dose and timing of use, the appropriate MI/DCI ratio, as well as the potential side effects of excess DCI and the problem of inositol resistance, require further comprehensive studies.

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

Background: Menstrual cycle disorders represent a prevalent cause for gynecological consultations. These disorders often encompass ovulatory dysfunction, accompanied by analytical and clinical anomalies linked to hyperandrogenism, collectively defining polycystic ovary syndrome (PCOS). However, a considerable subset of patients suffering from menstrual cycle disorders fails to meet the diagnostic criteria for any recognized PCOS phenotypes, leading to substantial debate in the field. This study aims to assess the impact of a commercially available combination of inositols, melatonin, folic acid, and vitamin D in patients experiencing menstrual disorders, characterized by oligo-anovulation (amenorrhea and abnormally long cycles), irrespective of their actual compliance with PCOS criteria. Methods: An observational, prospective, non-randomized study was devised to assess cycle regularity, satisfaction levels, and analytical alterations following the administration of the combination of inositols, melatonin, folic acid, and vitamin D (at baseline and at 6 months). Statistical analysis was executed using SPSS (version 22.0). Results: The assessed treatment demonstrated an enhancement in the regularity of menstrual cycles, accompanied by notable reductions in androstenedione and dehydroepiandrosterone (DHEA) levels, as well as basal insulin and the homeostatic model assessment for insulin resistance (HOMA), despite their initial values falling within the normal range. Furthermore, there was a substantial elevation in the serum levels of vitamin D (p < 0.05). Following 6 months of treatment, a high degree of patient satisfaction was observed, with no documented adverse effects within the selected sample. Conclusions: The combination of inositols, melatonin, folic acid, and vitamin D exhibits potential as an efficacious approach for managing menstrual disorders while maintaining a commendable safety profile. Additional investigations into the long-term efficacy and safety of this formulation are warranted, although initial results hold promise.

D-chiro-inositol (DCI) is an isomer of inositol, abundant in many foods, such as beans and buckwheat, with insulin-sensitizing, anti-inflammatory, and antioxidant effects. DCI has been used to relieve insulin resistance in diabetes and polycystic ovary syndrome in combination with inositol or D-pinitol. Here, we investigated the effect of DCI on aging and stress resistance in C. elegans. We found that DCI could prolong the lifespan of C. elegans by up to 29.6 %. DCI significantly delayed the onset of neurodegenerative diseases in models of C. elegans. DCI decreased the accumulation of Aβ1–42, alpha-synuclein, and poly-glutamine, the pathological causes of Alzheimer's, Parkinson's, and Huntington's diseases, respectively. DCI significantly increased the stress resistances against pathogens, oxidants and heat shock. Moreover, D-chiro-inositol reduced the content of ROS and malondialdehyde by increasing the total antioxidant capacity and the activity of superoxide dismutase and catalase. Above effects of DCI requires the transcription factors FOXO/DAF-16 and Nrf-2/SKN-1. DCI also increased the expression of downstream genes regulated by FOXO/DAF-16 and Nrf-2/SKN-1. In conclusion, DCI enhanced the antioxidant capacity and healthy lifespan of C. elegans by activating DAF-16, SKN-1, and HSF-1. Our results showed that DCI could be a promising antiaging agent that is worth further research on the mechanism and health supplemental application of DCI.

Metabolic syndrome (MetS) is associated with cardiovascular risk factors, such as insulin resistance, dyslipidaemia, hypertension and abdominal obesity. Given the growing need to investigate food supplements with positive health effects, this study was aimed at testing the benefits of a specific supplement for people with MetS. Fifty-eight subjects with MetS and T2DM or impaired glucose tolerance assuming metformin, were randomly assigned to take a food supplement of glucomannan, D-chiro-inositol, Cinnamomum zeylanicum blume and inulin at a daily fixed dose of 4 g orally for four months. Body weight, waist circumference, plasma lipid profile (total cholesterol, LDL, HDL and triglyc-erides), plasma glycaemic profile and visceral adiposity index (VAI) were measured at baseline and after four months of supplementation. After 16 weeks, in subjects with T2DM or insulin resistance who took the supplement (+ metformin), there was a significant reduction in body weight and BMI (p < 0.0001), serum insulin (p < 0.05) and the HOMA index (p < 0.01), as well as in the lipaemic pattern, with a significant improvement in total serum cholesterol (p < 0.005), triglycerides (p < 0.03) and LDL (p < 0.02). Our study shows that the food supplement tested is a valid and safe alternative therapeutic approach in the management of MetS and all its resulting risk factors, as its efficacy has been demonstrated across anthropometric, glucose, lipid and hepatic parameters.

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

This paper describes the development of a simple voltammetric biosensor for the stereoselective discrimination of myo-inositol (myo-Ins) and D-chiro-inositol (D-chiro-Ins) by means of bovine serum albumin (BSA) adsorption onto a multi-walled carbon nanotube (MWCNT) graphite screen-printed electrode (MWCNT-GSPE), previously functionalized by the electropolymerization of methylene blue (MB). After a morphological characterization, the enantioselective biosensor platform was electrochemically characterized after each modification step by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The results show that the binding affinity between myo-Ins and BSA was higher than that between D-chiro-Ins and BSA, confirming the different interactions exhibited by the novel BSA/MB/MWCNT/GSPE platform towards the two diastereoisomers. The biosensor showed a linear response towards both stereoisomers in the range of 2–100 μM, with LODs of 0.5 and 1 μM for myo-Ins and D-chiro-Ins, respectively. Moreover, a stereoselectivity coefficient α of 1.6 was found, with association constants of 0.90 and 0.79, for the two stereoisomers, respectively. Lastly, the proposed biosensor allowed for the determination of the stereoisomeric composition of myo-/D-chiro-Ins mixtures in commercial pharmaceutical preparations, and thus, it is expected to be successfully applied in the chiral analysis of pharmaceuticals and illicit drugs of forensic interest.

Polycystic ovary syndrome is an endocrine disorder often characterized by insulin resistance and hyperinsulinemia, especially in overweight/obese women. Among insulin sensitizers, the positive role of inositols has been increasingly established in recent years. The action of inositols not only concerns the metabolic parameters of these patients, but also the hormonal profile, resulting in beneficial effects on ovarian function. For this reason, many studies have tried to recognize their role in PCOS infertile women who underwent in vitro fertilization (IVF) procedures.

Despite the chemical similarities between myo-inositol and D-chiro-inositol and their synergistic effects on insulin sensitivity, they serve different functions. Insulin resistance is one of the etiological factors in the development of polycystic ovary syndrome (PCOS), diabetes mellitus, metabolic syndrome, infertility, menstrual irregularities and ovulation disorders, pregnancy complications, in particular, gestational diabetes. Myo-inositol plays an important role in the insulin transfer and hormone synthesis in the ovaries, in oocyte maturation, fertilization, implantation and post-implantation development. Many studies confirm the positive effect of inositol isomers on metabolic, hormonal and reproductive disorders, both in the form of monotherapy and in combination with other drugs to enhance the therapeutic effect and bioavailability. Myo-inositol has a favorable safety profile. Studies have shown that in patients with PCOS myo-inositol improves ovarian function and fertility, reduces the manifestations of hyperandrogenism, insulin resistance and normalizes weight. Myo-inositol and D-chiro-inositol have different mechanisms of action on insulin sensitivity and have different functions. The balance of the two isomers ensures the normal secretion of hormones and ovarian functioning, but it is currently unknown what the optimal ratio of these two isomers due to the small number of high quality studies and the difficulty of studying their isolated action. There are currently different combinations of myo- and D-chiro-inisotol, but they also have not been supported by enough high quality studies. When prescribing various isomers of inositol, it should be remembered that doses above 4000 mg are the most studied in patients with PCOS, but D-chiro-inositol concentration above 1200 mg/day has undesirable effects. Most studies indicate that D-chiro-inositol value is increased in PCOS, therefore oocytes are more sensitive to its overdose, and combination drugs require more study. Currently, there is no consensus in the literature on the advantage of combined supplements of myo- and D-chiro-inositol compared to monotherapy with myo-inositol. Today, myo-inositol monotherapy is more researched and safer.

Résumé Contexte Plusieurs articles de revues récents rapportent que le D-chiro-inositol (DCI), principalement connu sous le nom de second messager de l’insuline, influence la stéroïdogenèse. En particulier, de nouvelles preuves apparaissent sur la capacité du DCI à réguler l’expression de l’aromatase et la biosynthèse de la testostérone. À cet égard, l’administration de DCI pourrait représenter une bonne opportunité thérapeutique en cas de réduction des taux de testostérone. Les hommes d’âge avancé ont généralement des concentrations de testostérone plus faibles que celles d’hommes plus jeunes, et de récents essais contrôlés randomisés ont examiné, si le traitement par testostérone pourrait améliorer dans ce groupe d’âge les résultats en matière de santé. Il existe peu d’informations sur l’innocuité de cette thérapie de remplacement de la testostérone chez ces hommes ; le DCI pourrait ainsi constituer une intéressante alternative pour de futurs essais. Par conséquent, la présente étude vise à évaluer l’effet du traitement par DCI sur les taux de testostérone chez les hommes d’âge avancé. Résultats Dix hommes d’âge avancé ayant un faible taux basal de testostérone ont été recrutés dans la présente étude. Les patients ont pris 600 mg de DCI, deux fois par jour, pendant 30 jours. Nous avons évalué les paramètres hormonaux et glycémiques, le poids, le tour de taille et l’indice de masse corporelle au départ (T0) et après 30 jours (T1). Enfin, tous les patients ont également rempli le questionnaire normalisé de l’indice international de la fonction érectile et ont effectué le test de force de préhension (handgrip test) à T0 et T1. Les hommes prenant le DCI ont présenté des concentrations augmentées d’androgènes et réduites d’œstrogènes, ainsi qu’une amélioration des profils glycémiques. La prise de DCI était également associée à une réduction du poids, de l’indice de masse corporelle, du tour de taille, et à une amélioration de la force de préhension et de la fonction sexuelle autodéclarée. Tous ces effets ont conduit à une amélioration de la fonction sexuelle et de la force physique. Conclusions Dans cette étude pilote, le traitement par DCI a amélioré les taux de testostérone et d’androstènedione au détriment des œstrogènes chez des hommes d’âge avancé ayant de faibles taux de base de ces hormones, sans effets indésirables.

ABSTRACT Inositols (cyclohexanehexols) comprise nine isomeric cyclic sugar alcohols, several of which occur in all domains of life with various functions. Many bacteria can utilize inositols as carbon and energy sources via a specific pathway involving inositol dehydrogenases (IDHs) as the first step of catabolism. The microbial cell factory Corynebacterium glutamicum can grow with myo-inositol as a sole carbon source. Interestingly, this species encodes seven potential IDHs, raising the question of the reason for this multiplicity. We therefore investigated the seven IDHs to determine their function, activity, and selectivity toward the biologically most important isomers myo-, scyllo-, and d-chiro-inositol. We created an ΔIDH strain lacking all seven IDH genes, which could not grow on the three inositols. scyllo- and d-chiro-inositol were identified as novel growth substrates of C. glutamicum. Complementation experiments showed that only four of the seven IDHs (IolG, OxiB, OxiD, and OxiE) enabled growth of the ΔIDH strain on two of the three inositols. The kinetics of the four purified enzymes agreed with the complementation results. IolG and OxiD are NAD+-dependent IDHs accepting myo- and d-chiro-inositol but not scyllo-inositol. OxiB is an NAD+-dependent myo-IDH with a weak activity also for scyllo-inositol but not for d-chiro-inositol. OxiE on the other hand is an NAD+-dependent scyllo-IDH showing also good activity for myo-inositol and a very weak activity for d-chiro-inositol. Structural models, molecular docking experiments, and sequence alignments enabled the identification of the substrate binding sites of the active IDHs and of residues allowing predictions on the substrate specificity. IMPORTANCE myo-, scyllo-, and d-chiro-inositol are C6 cyclic sugar alcohols with various biological functions, which also serve as carbon sources for microbes. Inositol catabolism starts with an oxidation to keto-inositols catalyzed by inositol dehydrogenases (IDHs). The soil bacterium C. glutamicum encodes seven potential IDHs. Using a combination of microbiological, biochemical, and modeling approaches, we analyzed the function of these enzymes and identified four IDHs involved in the catabolism of inositols. They possess distinct substrate preferences for the three isomers, and modeling and sequence alignments allowed the identification of residues important for substrate specificity. Our results expand the knowledge of bacterial inositol metabolism and provide an important basis for the rational development of producer strains for these valuable inositols, which show pharmacological activities against, e.g., Alzheimer’s disease, polycystic ovarian syndrome, or type II diabetes.

Introduction: Myo-inositol (MYO) and D-chiro-inositol are chemical compounds known to exert an impact on multiple signaling pathways of a human body. Due to its effects on insulin metabolism and ovaries’ hormone activity their use in polycystic ovary syndrome (PCOS) therapies has been highly recommended in the recent literature. In this article we aim to review the known and possible applications of inositol and its derivatives for treatment of various gynecological and endocrine disorders and to indicate possible directions of further investigations. Methods and materials: This article is based on the literature found in PubMed Database from the period of 2016-2022 with use of keywords such as “inositol”; “myoinositol”; “d-chiro-inositol”; “PCOS”; “insulin”. Results: The applications of myoinositol in the treatment of polycystic ovary syndrome (PCOS) are very well known in recent publications. It is reported that MYO supplementation improves the quality of oocytes, regulates the menstrual cycle and ovulation rates. Prevention of gestational diabetes (GDM) amongst the patients with risk factors is likely another use of inositols. Inositol takes part in phospholipase C pathway, thus its depletion may be the cause for hypothyroidism. Inositol inhibits the expression of aromatase, the enzyme which is responsible for the growth of endometrial tissue - it may constitute a targeting point in the treatment of endometriosis. So far, no adverse effects of inositol isomers have been reported. Conclusion: The use of inositol, its isomers and derivatives represents an interesting direction in the development of the treatment of many conditions associated with endocrine disorders. There is a need for further investigations and studies on larger groups of patients to exploit its potential.

The primary control of dysmetabolic patients is extremely challenging worldwide, with inadequate dietary habits and sporadic physical activity among the key risk factors for metabolic syndrome onset. Nowadays, there is no exclusive treatment for this condition, and considering that preventive measures usually fail, new therapeutic approaches need to be proposed and investigated. This present pilot study compared the effects of diet alone and in association with a combination of myo-inositol and d-chiro-inositol in their 40:1 ratio, α-lactalbumin, and Gymnema sylvestre on different metabolic parameters in obese dysmetabolic patients. To this purpose, 37 patients with BMI between 30 and 40 and fasting blood glucose between 100 and 125 mg/dL were divided into two groups: (i) the control group followed a hypocaloric Mediterranean diet, (ii) while the study group was also supplemented with a daily dosage of two sachets, each one containing 1950 mg myo-inositol, 50 mg d-chiro-inositol, 50 mg α-lactalbumin, and 250 mg Gymnema Sylvestre. After a 6-month treatment, all parameters improved in both groups. Nevertheless, the treated group experienced a greater improvement, especially concerning the variation from the baseline of HOMA index, triglycerides, BMI, body weight, and waist circumference. These findings support the supplementation with myo-inositol and d-chiro-inositol in the 40:1 ratio, α-lactalbumin, and Gymnema sylvestre as a therapeutical strategy to potentiate the beneficial effects induced via dietary programs in dysmetabolic patients.

Endometrial hyperplasia is a threatening pathology driven by unopposed estrogen stimulus. Moreover, insulin may act on the endometrium, prompting further growth. We aimed at assessing whether D-chiro-Inositol, an insulin sensitizer with estrogen-lowering properties, might improve the condition of patients with simple endometrial hyperplasia without atypia. We enrolled women with simple endometrial hyperplasia without atypia and related symptoms, including abnormal uterine bleeding. We treated the patients with one tablet per day, containing 600 mg of D-chiro-inositol for six months. Patients underwent ultrasound to assess the thickness of the endometrium at baseline, after three months, and at the end of this study. Endometrial thickness went from 10.82 ± 1.15 mm to 8.00 ± 0.81 mm after three months (p < 0.001) and to 6.9 ± 1.06 mm after six months (p < 0.001 versus baseline; p < 0.001 versus three months). D-chiro-inositol treatment also improved heavy menstrual bleeding and the length of menstruation. Despite the fact that our data should be validated in larger studies with appropriate control groups, our promising results support the hypothesis that D-chiro-inositol may represent a useful treatment in the case of endometrial hyperplasia without atypia.

Diabetic osteoporosis (DO) has been increasingly recognized as an important complication of diabetes. D-pinitol, a natural compound found in various legumes, is known for its anti-diabetic function, but its effect on DO has not been investigated. Two doses of pinitol (50 and 100 mg/kg Bw/d) were administered orally to experimentally induce the DO mouse model for 5 weeks. The results indicated that pinitol suppressed fasting blood glucose levels and tended to enhance impaired pancreatic function. Pinitol also suppressed serum bone turnover biomarkers, and improved dry femur weight, cancellous bone rate, and bone mineral content in the DO mice. Based on the inositol quantification using GC-MS in serum, liver, kidney, and bone marrow, the pinitol treatment significantly recovered the depleted D-chiro-inositol (DCI) content or the decreased the ratio of DCI to myo-inositol caused by DO. In short, our results suggested that pinitol improved glucose metabolism and inhibited bone loss in DO mice via elevating the DCI levels in tissues.

Introduction: Polycystic Ovarian Syndrome (PCOS) is known to be an endocrine state that is characterized by oligomenorrhea, hyperandrogenism, and highly cystic follicles in the ovaries. The use of food ingredients and traditional medicine in Asian countries is well known, and previous studies have shown that Ecklonia cava K. [Alariaceae] (EC) is able to alleviate PCOS symptoms. D-Chiro-inositol (DCI) administration in pathologies where steroid biosynthesis is a crucial factor, i.e., PCOS, has provided satisfactory results.Methods: Therefore, we studied the synergistic effects of the two previously known active compounds. In rats with letrozole-induced PCOS, we focused on alternative therapies using EC and/or DCI extracts to alleviate ovarian failure.Results: As a nonsteroidal aromatase inhibitor, letrozole inhibits the conversion of testosterone to estrogen and subsequently causes PCOS. We divided 6-week-old female mice into the following six groups and evaluated them: vehicle, PCOS, PCOS + MET (metformin), PCOS + DCI, PCOS + EC, and PCOS + DCI + EC. In our study, PCOS rats treated with EC and DCI had low serum LH and T levels and low serum levels of inflammatory cytokines such as TNFα and IL-6. These treatments also appeared to regulate the production of factors that affect follicle formation and inflammation in the ovaries.Conclusion: We concluded that EC extract and/or DCI administration influenced aromatase production and reduced LH and T stimulation, and cotreatment with EC and DCI consequently restored ovarian dysfunction or anti-inflammatory responses in rats with PCOS-like symptoms.

Increasing evidence shows that hypothalamic dysfunction, insulin resistance, and weight loss precede and progress along with the cognitive decline in sporadic Alzheimer’s Disease (AD) with sex differences. This study aimed to determine the effect of oral dietary administration of D-Chiro-inositol (DCI), an inositol used against insulin resistance associated with polycystic ovary, on the occurrence of metabolic disorders in the transgenic 5xFAD mouse model of AD (FAD: Family Alzheimer's Disease). DCI was administered from 6 to 10 months of age to male and female 5xFAD mice and control (non-Tg) littermates. Energy balance and multiple metabolic and inflammatory parameters in the hypothalamus, liver and plasma were evaluated to assess the central and peripheral effects of DCI. Results indicated that weight loss and reduced food intake in 5xFAD mice were associated with decreased neuropeptides controlling food intake and the appearance of a pro-inflammatory state in the hypothalamus. Oral administration of DCI partially restored energy balance and hypothalamic parameters, highlighting an increased expression of Npy and Agrp and female-specific downregulation of Gfap and Igf1. DCI also partially normalized impaired insulin signaling and circulating insulin, GLP-1, and GIP deficiencies in 5xFAD mice. Principal component analysis of metabolic parameters indicated the presence of a female-specific fatty liver in 5xFAD mice: DCI administration reversed hepatic fat accumulation, β-oxidation, inflammation and increased GOT and GPT levels. Our study depicts that metabolic impairment along with the cognitive decline in a mouse model of AD, which is exacerbated in females, can be ameliorated by oral supplementation with insulin-sensitizing DCI.

White adipose tissue/brown adipose tissue trans-differentiation is one of the main study targets for therapies against obesity and metabolic diseases. In recent years, numerous molecules able to induce such trans-differentiation have been identified; however, their effect in obesity therapies has not been as expected. In the present study, we investigated whether myo-inositol and its stereoisomer D-chiro-inositol could be involved in the browning of white adipose tissue. Our preliminary results clearly indicate that both, at 60 μM concentration, induce the upregulation of uncoupling protein 1 mRNA expression, the main brown adipose tissue marker, and increase mitochondrial copy number as well as oxygen consumption ratio. These changes demonstrate an activation of cell metabolism. Therefore, our results show that human differentiated adipocytes (SGBS and LiSa-2), assume the features typical of brown adipose tissue after both treatments. Furthermore, in the cell lines examined, we proved that D-chiro-inositol and myo-Inositol induce an increase in the expression of estrogen receptor mRNAs, suggesting a possible modulation by these isomers. We also found an increase in the mRNA of peroxisome proliferator-activated receptor gamma, a very important target in lipid metabolism and metabolic diseases. Our results open new opportunities for the use of inositols in therapeutic strategies to counteract obesity and its metabolic complications.

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

Polycystic ovary syndrome (PCOS) is a symptom complex associated with increased amounts of circulating androgens in females, increased insulin resistance and obesity. The drugs, Myo-inositol, D-chiro-inositol and Metformin, which are insulin sensitizers, are very helpful in taking care of one of the key components of PCOS that is insulin resistance. Myoinositol and D-chiro-inositol are isomeric forms of inositol that have insulin-like properties, acting as second messengers in the insulin intracellular pathway; both of these molecules are involved in the increasing insulin sensitivity of different tissues to improve metabolic and ovulatory functions. This study was done to compare the effects of combination of Myo-inositol and D-chiro-inositol with the use of metformin on clinical and biochemical profile in PCOS. Methods. A prospective, randomized, comparative study was conducted on 200 patients. The patients were randomly assigned into the two groups of 100 each. Group A receiving Tab. Myoinositol 550mg twice daily and Tab. D-chiro-inositol 13.8mg twice daily and Group B receiving Tab. Metformin 500mg thrice daily. The patients were assessed by menstrual cycle regulation, hirsutism score (Ferriman Gallwey), fasting and postprandial glucose and insulin levels, serum dehydroepiandrosterone levels, serum free testosterone levels and serum luteinizing and follicle stimulating hormone ratio. Results. In both the groups there was significant improvement in all the above mentioned parameters, however the group with Combination of Myo-inositol and D-chiro-inositol had statistically significant improvement over the Metformin group. Conclusions: Combination of Myo-inositol and D-chiro-inositol and use of metformin, significantly improved insulin sensitivity in PCOS women. But combination of Myo-inositol and D-chiro-inositol was effective in controlling the hormonal profiles (luteinizing/follicle stimulating hormone ratio and free testosterone) when compared to Metformin.

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

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

Dietary supplements have improved the prevention of insulin resistance and metabolic diseases, which became a research hotspot in food science and nutrition. Obesity and insulin resistance, caused by a high-fat diet, eventually result in severe metabolic diseases, can be prevented with the dietary supplement D-chiro-inositol (DCI). In this work, we isolated mice primary hepatocytes with palmitic acid stimulation and DCI was applied to compare and contrast its effects of in primary hepatocyte biology. Before and after intervention with DCI, we used RNA-Seq technology to establish a primary hepatocyte transcriptome gene profile. We found that both PA and DCI cause a wide variation in gene expression. Particularly, we found that DCI plays critical role in this model by acting on glycolysis and gluconeogenesis. Overall, we generated extensive transcripts from primary hepatocytes and uncovered new functions and gene targets for DCI.

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

Abstract D-pinitol is one of the major inositol found in plants and studies suggest its potential hypoglycemic and hypolipidemic actions in diabetic rodents. Here, we investigated the actions of D-pinitol on adiposity, and in lipid and glycemic homeostasis in monosodium glutamate (MSG)-obese mice. Swiss mice received daily subcutaneous injections of MSG [(4g/kg of body weight (BW)] or saline [1.25g/kg BW; control (CTL)] during their first five days of life. From 90-120 day-old, half of the MSG and CTL groups received 50 mg D-pinitol/kg BW/day (MPIN and CPIN groups) or vehicle (saline; MSG and CTL groups) by gavage. MSG mice displayed higher abdominal adiposity and hepatic triglycerides (TG) deposition, and increased hepatic expression of lipogenic genes (SREBP-1c, ACC-1 and FASN), but downregulation in AMPKα mRNA. MSG mice also exhibited hyperinsulinemia, islet hypersecretion and hypertrophy, glucose intolerance and insulin resistance. D-pinitol did not change adiposity, glucose intolerance, insulin resistance, but increased hepatic triglycerides (TG) content in MPIN mice, which was associated with increases in gene expressions of SREBP-1c and FASN, but reduction in AMPKα. Furthermore, D-pinitol enhanced insulin secretion in MPIN and CPIN groups. Therefore, D-pinitol enhanced glucose-induced insulin secretion, which may account to enhances hepatic lipogenesis and TG deposition in MPIN mice.

In this study, we observed the effect of D-chiro-inositol (DCI) on glucose consumption in type 2 diabetic db/db mice, and investigated the relevant mechanism. We discovered that the stability of 24-h blood glucose under the nonfasting condition and decreased glucose tolerance were both alleviated after treatment with DCI. Moreover, the content of glycosylated protein and advanced glycation end products in the serum was reduced, the damage in the liver tissue was alleviated, and the synthesis of liver glycogen was significantly promoted. In addition, DCI increased the expression of insulin receptor substrate 2 (IRS2), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), glucose transporters 4 (GLUT4), and phospho-AKT (S473) protein. In contrast, DCI decreased the expression level of glycogen synthase kinase 3β (GSK3β) protein in liver tissue to various degrees, as shown by immunohistochemistry and western blotting. Furthermore, DCI increased the mRNA expression of IRS2, PI3K, AKT, and GLUT4, and reduced that of GSK3β in liver tissue, as demonstrated by polymerase chain reaction. Finally, DCI promoted glucose consumption in high glucose-stimulating HepG2 cells and increased the expression of IRS2 protein in HepG2 cells, as revealed by fluorescence staining and flow cytometry. Our results indicate that DCI can significantly improve glucose metabolism in diabetic mice and HepG2 cells. This effect may be associated with the upregulation of IRS2, PI3K, AKT, and GLUT4 and downregulation of GSK3β.

D-chiro-inositol is one of the nine stereoisomers of inositol, a water-soluble cyclic carbohydrate with six hydroxyl groups. Inositol has an essential function in the activation of crucial enzymes in glucose metabolism. In fact, D-chiro-inositol shortage can lead to insulin resistance development. D-chiro-inositol administration in pathologies where insulin resistance is an important factor, i.e. diabetes, has given satisfying results; however, in other disorders, i.e. Polycystic ovary syndrome, this stereoisomer can be detrimental for pregnancy. Indeed, high follicular D-chiro-inositol levels in the presence of reduced myo-inositol values are associated with worsened oocyte quality. In conclusion, some recent studies and researches suggest that restoring the physiologic ratio between myo-inositol and D-chiro-inositol is mandatory to protect the efficiency of the reproductive system in women.

Oxidative stress is the result of overproduction of reactive oxygen species in relation to antioxidant defense levels. Physiological oxidative stress a priori exists in the women and men, but with an excess of radical compounds, it can acquire a pathological character. Oxidative stress may contribute to aging and several diseased states affecting female and male reproduction. Endothelial dysfunction secondary to oxidative stress contributes to the development of obstetric complications such as early and recurrent pregnancy loss, preeclampsia, intrauterine growth restriction, and preterm labor. Reactive oxygen and nitrogen species can negatively affect embryo implantation and may influence the development of reproductive disorders such as endometriosis and preeclampsia. Altered vasomotor functions have been demonstrated by failed embryo implantation and reduced placental perfusion in preeclampsia and endometriosis. The effects of free radicals on oocytes, sperm, and embryos have been implicated in poor reproductive outcomes in assisted reproductive techniques. The in vitro environment subjects gametes and embryos to an abundance of reactive oxygen species in the absence of enzymatic antioxidant defenses that are normally present during in vivo fertilization and pregnancy. Ideally, assisted reproductive techniques success may be attained if in vivo conditions are sufficiently imitated. To this effect, several studies have shown that antioxidants and vitamines may improve pregnancy outcomes. D-chiro-inositol (DCI) is one of such promising substances. It increases fertility due to the ovulation restoration in patients with polycystic ovaries syndrome, improves the oocytes quality, reduces oxidative and inflammatory stress, that is increases the conception probability including in assisted reproductive technologies. This gave impetus to the active inositol preparations use in the clinics of assisted reproductive technologies to obtain good quality oocytes, and reduce the hormones dose used in ovaries stimulation.

D-chiro-inositol (DCI) is a natural compound detectable in cell membranes, which is highly conserved as a biological signaling molecule. In mammals, its function is primarily characterized in the intracellular transduction cascade of insulin. In particular, insulin signal promotes the release of pivotal DCI-containing molecules. In fact, impaired release of DCI is a common feature of insulin-resistant tissues, and insulin-sensitizing pharmaceuticals induce higher concentrations of free DCI. Moreover, it also plays important roles in several other processes. DCI is involved in the regulation of steroidogenesis, due to its regulatory effects on steroidogenic enzymes, including 17α-hydroxylase, 3β-hydroxysteroid dehydrogenase, and aromatase. Such regulation of various enzymes indicates a mechanism by which the body regulates different processes via a single molecule, depending on its concentration. DCI also reduces the expression of integrin β3, which is an adhesion molecule involved in embryo implantation and cellular phenomena such as survival, stemness, and invasiveness. In addition, DCI seems to have important anti-inflammatory activities, like its 3-O-methyl-ether, called pinitol. In vitro evidence demonstrates that treatment with both compounds induces a reduction in pro-inflammatory factors—such as Nf-κB—and cytokines—such as TNF-α. DCI then plays important roles in several fundamental processes in physiology. Therefore, research on such molecule is of primary importance.

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

Inositols are natural molecules involved in several biochemical and metabolic functions in different organs and tissues. The term “inositols” refers to five natural stereoisomers, among which myo-Inositol (myo-Ins) is the most abundant one. Several mechanisms contribute to regulate cellular and tissue homeostasis of myo-Ins levels, including its endogenous synthesis and catabolism, transmembrane transport, intestinal adsorption and renal excretion. Alterations in these mechanisms can lead to a reduction of inositols levels, exposing patient to several pathological conditions, such as Polycystic Ovary Syndrome (PCOS), hypothyroidism, hormonal and metabolic imbalances, like weight gain, hyperinsulinemia, dyslipidemia, and metabolic syndrome. Indeed, myo-Ins is involved in different physiological processes as a key player in signal pathways, including reproductive, hormonal, and metabolic modulation. Genetic mutations in genes codifying for proteins of myo-Ins synthesis and transport, competitive processes with structurally similar molecules, and the administration of specific drugs that cause a central depletion of myo-Ins as a therapeutic outcome, can lead to a reduction of inositols levels. A deeper knowledge of the main mechanisms involved in cellular inositols depletion may add new insights for developing tailored therapeutic approaches and shaping the dosages and the route of administration, with the aim to develop efficacious and safe approaches counteracting inositols depletion-induced pathological events.

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

Myo-inositol (MI) supplementation in women with polycystic ovary syndrome (PCOS) has been evaluated over the last years. Many hormonal and reproductive impairments associated with this disorder seem relieved by the supplement. The objective of the meta-analysis was to assess the effects of MI alone or combined with d-chiro-inositol (DCI) on the endocrine and metabolic abnormalities of women with PCOS. Literature was retrieved from selected databases, MEDLINE, EMBASE, PubMed and Research Gate (up to November 2016). Only randomized controlled trials (RCTs) investigating the effects of MI alone or combined with DdCI were reviewed. Nine RCTs involving 247 cases and 249 controls were included. Significant decreases in fasting insulin (SMD = −1.021 μU/mL, 95% CI: −1.791 to −0.251, P = 0.009) and homeostasis model assessment (HOMA) index (SMD = −0.585, 95% CI: −1.145 to −0.025, P = 0.041) were identified after MI supplementation. The trial sequential analysis of insulin meta-analysis illustrates that the cumulative z-curve crossed the monitoring boundary, providing firm evidence of the intervention effect. A slight trend toward a reduction of testosterone concentration by MI with respect to controls was found (SMD = −0.49, 95% CI: −1.072 to 0.092, P = 0.099), whereas androstenedione levels remained unaffected. Throughout a subgroup’s meta-analysis, a significant increase in serum SHBG was observed only in those studies where MI was administered for at least 24 weeks (SMD = 0.425 nmol/L, 95% CI: 0.050–0.801, P = 0.026). These results highlight the beneficial effect of MI in improving the metabolic profile of women with PCOS, concomitantly reducing their hyperandrogenism.

This review describes the mechanistic, animal, and clinical data related to the use of inositols in midlife. It covers studies related to the mechanism of action of myo-inositol and D-chiro-inositol and randomized controlled trials conducted in postmenopausal women with metabolic syndrome and supports these data with the results of in vitro and animal studies on inositol in nephropathy and other related conditions. Recent advances related to biochemistry, pharmaceutical science, and genetics are discussed. It concludes that inositols have a potential role to play in maintaining metabolic health in postmenopausal women.

Myo-inositol has been established as an important growth-promoting factor of mammalian cells and animals. The role of myo-inositol as a lipotropic factor has been proven, in addition to its involvement as co-factors of enzymes and as messenger molecules in signal transduction. Myo-inositol deficiency leads to intestinal lipodystrophy in animals and “inositol-less death” in some fungi. Of late, diverse uses of myo-inositol and its derivatives have been discovered in medicinal research. These compounds are used in the treatment of a variety of ailments from diabetes to cancer, and continued research in this direction promises a new future in therapeutics. In different diseases, inositols implement different strategies for therapeutic actions such as tissue specific increase or decrease in inositol products, production of inositol phosphoglycans (IPGs), conversion of myo-inositol (MI) to D-chiro-inositol (DCI), modulation of signal transduction, regulation of reactive oxygen species (ROS) production, etc. Though inositol pharmacology is a relatively lesser-known field, recent years of research has generated a critical mass of information on the subject. This review aims to summarize our current understanding on the role of inositol derivatives in ameliorating the symptoms of different diseases.

This review describes the rationale, biochemical, and clinical data related to the use of inositols in polycystic ovary syndrome (PCOS). It covers studies related to the mechanism of action of myo-inositol and D-chiro-inositol (MDI), with randomized controlled trials conducted in women with PCOS, and utilizes these data to suggest pragmatic indications and methods for using MDI combination in PCOS. Rationally crafted inositol combinations have a potential role to play in maintaining metabolic, endocrine, and reproductive health in women with PCOS.

The insulin resistance state of pancreatic α-cells seems to be related to glucagon hypersecretion in type 2 diabetes. Treatment that can improve the insulin sensitivity of α-cells could control glucagon levels in patients with diabetes mellitus. The aim of this study was to investigate the preventive role of D-chiro-inositol (DCI), which has insulin receptor-sensitizer effects on insulin signaling pathways and glucagon secretion in pancreatic α-TC1 clone 6 cells. Cells were chronically treated with palmitate to induce insulin resistance in the presence/absence of DCI. DCI treatment improved the insulin signaling pathway and restored insulin-mediated glucagon suppression in α-TC1-6 cells exposed to palmitate. These results indicate that DCI treatment prevents the insulin resistance of α-TC1-6 cells chronically exposed to palmitate. Our data provide evidence that DCI could be useful to improve the insulin sensitivity of pancreatic α-cells in diabetes treatment.

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

Polycystic ovarian syndrome (PCOS) is the main cause of female infertility. It is a multifactorial disorder with varying clinical manifestations including metabolic/endocrine abnormalities, hyperandrogenism, and ovarian cysts, among other conditions. D-Chiro-inositol (DCI) is the main treatment available for PCOS in humans. To address some of the mechanisms of this complex disorder and its treatment, this study examines the effect of DCI on reproduction during the development of different PCOS-associated phenotypes in aged females and two mouse models of PCOS. Aged females (8 months old) were treated or not (control) with DCI for 2 months. PCOS models were generated by treatment with dihydrotestosterone (DHT) on Days 16, 17, and 18 of gestation, or by testosterone propionate (TP) treatment on the first day of life. At two months of age, PCOS mice were treated with DCI for 2 months and their reproductive parameters analyzed. No effects of DCI treatment were produced on body weight or ovary/body weight ratio. However, treatment reduced the number of follicles with an atretic cyst-like appearance and improved embryo development in the PCOS models, and also increased implantation rates in both aged and PCOS mice. DCI modified the expression of genes related to oocyte quality, oxidative stress, and luteal sufficiency in cumulus-oocyte complexes (COCs) obtained from the aged and PCOS models. Further, the phosphorylation of AKT, a main metabolic sensor activated by insulin in the liver, was enhanced only in the DHT group, which was the only PCOS model showing glucose intolerance and AKT dephosphorylation. The effect of DCI in the TP model seemed mediated by its influence on oxidative stress and follicle insufficiency. Our results indicate that DCI works in preclinical models of PCOS and offer insight into its mechanism of action when used to treat this infertility-associated syndrome.

The use of inositols in endocrinological clinical practice is increasingly widespread. Most of the existing evidence concerns myoinositol (MYO), the most abundant form in nature, especially in women with polycystic ovarian syndrome. We have previously shown that MYO increases sperm motility in patients with asthenozoospermia by the increase of sperm mitochondrial membrane potential (MMP), a biofunctional sperm parameter closely associated to sperm motility. The aim of this study was to evaluate the effects of D-chiro-inositol (DCI), another biologically active isoform of inositols, on sperm MMP, as data on this matter has never been released so far. To accomplish this, semen samples from 15 patients with asthenozoospermia and 15 healthy normozoospermic men were incubated with increasing concentrations of DCI (0, 75, and 750 µg/mL) or phosphate buffer saline for 30 min. Incubation with DCI significantly improved sperm MMP at lower concentrations, and with shorter incubation length than those used in our similar MYO studies. In conclusion, these findings indicate that DCI positively impacts on sperm mitochondrial function in vitro. Studies aimed at assessing the role of DCI in the treatment of asthenozoospermia in-vivo are warranted.

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

A relatively high concentration of phytate in buckwheat malt, and the low activity of endogenous buckwheat phytases, both of which limit the effective use of substrates (starch, proteins, minerals) for fermentation and yeast metabolism, gives rise to the potential for application of phytases in beer production. This study aims at obtaining a 100% buckwheat wort with high bioactive cyclitols (myo-inositol and D-chiro-inositol) concentrations released by exogenous phytases and acid phosphatases. Two mashing programs were used in the study, i.e., (1) typical for basic raw materials, namely the well-established Congress method, and (2) optimized for phytase activity. The results indicated a nearly 50% increase in the level of bioactive myo-inositol and an 80% degradation of phytate in the wort as a result of simultaneous application of phytase and phosphatase enzymes in the mashing of buckwheat malt. In addition, high D-chiro-inositol concentrations were released from malt to the buckwheat wort. The concerted action of the two phytases significantly increased (19−44%) Zn2+ concentrations in wort. This may be of great importance during mash fermentation by Saccharomyces cerevisiae yeasts. There is a potential to develop technology for buckwheat beer production, which, in addition to being free from gluten, comprises high levels of bioactive myo- and D-chiro-inositols.

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

In this study, the relationship between the inhibitory effects of extracts from rye-buckwheat ginger cakes supplemented with low and high rutin dosage baked without or with dough fermentation step on the formation of fluorescent advanced glycation end-products (AGEs), and phenolic compounds, rutin, D-chiro-inositol and antioxidant capacity were addressed. The cakes were based on rye flour substituted by light buckwheat flour or flour from roasted buckwheat groats at 30% level, and were produced with or without dough fermentation step. The inhibitory effect against AGEs formation was studied in bovine serum albumin (BSA)-glucose and BSA-methylglyoxal (MGO) systems. The antioxidant capacity was measured by 2,2-diphenyl- -1-picrylhydrazyl (DPPH) and cyclic voltammetry (CV), rutin and D-chiro-inositol contents by HPLC and total phenolics (TPC) by spectrophotometric assays. The study showed the inhibitory effects of extracts from rye-buckwheat ginger cakes supplemented with low and high rutin dosage. The results of the inhibitory activity were highly correlated in two applied model systems. Enrichment of rye-buckwheat ginger cakes with rutin improved their antioxidant properties. The correlation studies showed that the inhibitory effects of rye-buckwheat ginger cakes produced with dough fermentation step and enhanced with rutin against formation of AGEs were highly correlated with TPC, rutin and D-chiro-inositol contents, and antioxidant capacity. Moreover, the effect of rutin enrichment was clearly seen in cakes obtained with dough fermentation step, even the inhibitory activity was slightly lower as compared to the cakes produced without dough fermentation.

Tartary buckwheat seed and especially its sprouts are rich in D-chiro-inositol (DCI). The research was to evaluate when DCI was most accumulated in tartary buckwheat sprouts. In addition, we explored the activity and expression pattern of α-galactosidase during tartary buckwheat seed germination. The results showed that DCI contents steadily increased at early stage of germination and reached the highest level of 33.42 µg/seed at 24 h during the 72 h trail. However, the total fagopyritol contents sharply decreased from 214.6 µg/seed to 46 µg/seed at the end of the germination. The activity of acid α-galactosidase increased gradually to the peak of 0.36 nkat/seed at 24 h after the primed seed imbibition. We cloned the gene fragment of α-galactosidase in tartary buckwheat for the first time. The deduced amino acid sequence is 93% identical to that of P. vulgaris. The quantitative PCR result of gene expression pattern was consistent with its enzyme activity during seed germination.

Polycystic ovary syndrome (PCOS) is characterized by hormonal abnormalities that cause menstrual irregularity and reduce ovulation rate and fertility, associated to insulin resistance. Myo-inositol (cis-1,2,3,5-trans-4,6-cyclohexanehexol, MI) and D-chiro-inositol (cis-1,2,4-trans-3,5,6-cyclohexanehexol, DCI) represent promising treatments for PCOS, having shown some therapeutic benefits without substantial side effects. Because the use of inositols for treating PCOS is widespread, a deep understanding of this treatment option is needed, both in terms of potential mechanisms and efficacy. This review summarizes the current knowledge on the biological effects of MI and DCI and the results obtained from relevant intervention studies with inositols in PCOS. Based on the published results, both MI and DCI represent potential valid therapeutic approaches for the treatment of insulin resistance and its associated metabolic and reproductive disorders, such as those occurring in women affected by PCOS. Furthermore, the combination MI/DCI seems also effective and might be even superior to either inositol species alone. However, based on available data, a particular MI:DCI ratio to be administered to PCOS patients cannot be established. Further studies are then necessary to understand the real contents of MI or DCI uptaken by the ovary following oral administration in order to identify optimal doses and/or combination ratios.

Cyclitols play a particularly important role in cell functioning because they are involved in ion channel physiology, phosphate storage, signal transduction, cell wall formation, membrane biogenesis, osmoregulation and they have antioxidant activity. They are involved in the cell membranes as a phosphatidyl myo-inositol, an inositol triphosphate precursor, which acts as a transmitter that regulates the activity of several hormones, such as follicle-stimulating hormone, thyrotropin, and insulin. The aim of this paper is to characterize the selected cyclitols: myo-inositol, D-chiro-inositol, and D-pinitol in type-2 metabolic syndrome and diabetes treatment. Results and discussion: Cyclitols have certain clinical applications in the treatment of metabolic syndromes and are considered to be an option as a dietary supplement for the treatment or prevention of gestational diabetes mellitus and type-2 diabetes. Improved metabolic parameters observed after using cyclitols, like myo-inositol, in the treatment of polycystic ovary syndrome and type-2 diabetes suggest that they may have a protective effect on the cardiovascular system. Pinitol, together with myo-inositol,maybe responsible for improving lipid profiles by reducing serum triglyceride and total cholesterol. Pinitol is also well-researched and documented for insulin-like effects. Myo-inositol, D-chiro-inositol, and D-pinitol indicate a number of therapeutic and health-promoting properties.

Introduction: Myo-inositol and its derivatives cyclitols play an important role in the processes of cell regulation, signal transduction, osmoregulation, and ion channel physiology, and are a component of the cell membrane. Free cyclitols present in food or released during the degradation of galactosyl cyclitols by bacteria (in digestive tract) show some physiological benefits. Aim: The aim of this paper is to present and analyze the documented data about curative and healing properties of cyclitols. Results and discussion: Cyclitols are well known compounds in the treatment of an accompanied diabetes insulin resistance, and also obesity and polycystic ovarian syndrome. d-chiro-Inositol deficiency exacerbates insulin resistance in the liver, muscles, and fat, while depletion of myo-inositol results in the development of diabetic complications. Cyclitols are successfully applied in treatment of polycystic ovarian syndrome, simultaneous are observed effective reducing of BMI, improving the hormonal profile, and increasing fertility. Moreover, cyclitols have anti-atherogenic, anti-oxidative, anti-inflammatory, and anti-cancer properties. Conclusion: The properties of cyclitols may be a good therapeutic option in the reduction of metabolically induced inflammation. Due to well drugs tolerance and low toxicity of these compounds, cyclitols are recommend for pregnant women and also for children. Another advantage is their widespread presence and easy availability, which encourages their use in medicine.