New Insights into the Activities of D-Chiro-Inositol: A Narrative Review

D-chiro-inositol effectively counteracts endometriosis in a mouse model

BACKGROUND

Endometriosis, a common condition affecting 5-10% of women of reproductive age, is the growth of endometrial-like tissue outside the uterus, leading to pain and infertility. Current treatments, such as surgery and hormonal therapy, offer limited long-term benefits. This study investigated the potential of D-chiro inositol (DCI), a natural compound that influences ovarian steroidogenesis, to treat endometriosis and compared its efficacy with a progestin drug such as Dienogest (DG).

METHODS

We established a non-surgical mouse model of endometriosis in CD1 mice. Uterine horns were removed from donor mice, cut into fragments and inoculated in recipient mice by intraperitoneal injection. Endometriosis progression was assessed at 15, 21 and 28 days after transplantation, with the 28-day window being the most effective. The mice were then randomly assigned to four experimental groups, which received for 28 days: water (EMS); DCI 0.4 mg/die (DCI); DCI 0.2 mg/die and Dienogest 0.33 ng/die (DCI + DG); DG 0.67 ng/die (DG). At the end of the treatments, endometriotic lesions, ovaries and circulating estradiol levels were analyzed.

RESULTS

The results showed that treatment with DCI, both alone and in combination with DG, significantly reduced the number, size and vascularization of endometriotic lesions compared to the EMS control group. Histological analysis confirmed a decrease in endometriotic foci across all treatment groups, with the most pronounced effects in the DCI group. To investigate the underlying molecular mechanisms, we found that DCI led to a significant reduction in the expression of Sirt1 and an increase in E-Cadherin, indicating a reduction in EMT transition relevant for lesion development. In addition, DCI decreased cell proliferation and,blood vessel formation, as evaluated by PCNA and CD34, respectively. Futhermore, in the ovary, DCI treatment downregulated the expression of aromatase (Cyp19a1), the enzyme critical for estrogen biosynthesis, and increased the number of primordial to antral follicles, suggesting a beneficial effect on ovarian folliculogenesis.

CONCLUSIONS

By modulating proliferation, EMT transition and aromatase activity, DCI emerges as a promising compound for endometriosis treatment.

Metabolic engineering Corynebacterium glutamicum for D-chiro-inositol production

D-chiro-inositol (DCI) is a potential drug for the treatment of type II diabetes and polycystic ovary syndrome. In order to effectively synthesize DCI in Corynebacterium glutamicum, the genes related to inositol catabolism in clusters iol1 and iol2 were knocked out in C. glutamicum SN01 to generate the chassis strain DCI-1. DCI-1 did not grow in and catabolize myo-inositol (MI). Subsequently, different exogenous and endogenous inosose isomerases were expressed in DCI-1 and their conversion ability of DCI from MI were compared. After fermentation, the strain DCI-7 co-expressing inosose isomerase IolI2 and inositol dehydrogenase IolG was identified as the optimal strain. Its DCI titer reached 3.21 g/L in the presence of 20 g/L MI. On this basis, the pH, temperature and MI concentration during whole-cell conversion of DCI by strain DCI-7 were optimized. Finally, the optimal condition that achieved the highest DCI titer of 6.96 g/L were obtained at pH 8.0, 37 °C and addition of 40 g/L MI. To our knowledge, it is the highest DCI titer ever reported.

The impact of epigallocatechin gallate, vitamin D, and D-chiro-inositol on early surgical outcomes of laparoscopic myomectomy: a pilot study

PURPOSE

A prospective investigation to assess the impact of 3 months of treatment with epigallocatechin gallate (EGCG), vitamin D and D-chiro-inositol (DCI) in the treatment of uterine fibroids (UF) with laparoscopic myomectomy as evidenced by surgical outcomes and effect on liver function.

METHODS

Non-pregnant or lactating women aged between 30 and 40 years were scheduled for laparoscopic myomectomy to treat symptoms or looking to conceive. After enrollment, patients were assigned to either (1) intervention group, assuming a total of 300 mg EGCG, 50 μg vitamin D, and 50 mg DCI divided in 2 pills per day for 3 months, or (2) control group, including untreated women scheduled to undergo laparoscopic myomectomy after 3 months.

RESULTS

91 patients completed the study. The comparison of the surgical outcomes between the intervention (n = 44) and the control (n = 47) groups revealed that the treatment significantly reduces the duration of surgery (41.93 ± 7.56 min vs 56.32 ± 10.63 min, p < 0.001). Moreover, the treatment also reduced blood loss during surgery (149.09 ± 25.40 mL vs 168.41 ± 21.34 mL, p < 0.001), resulting in treated patients having higher Hb levels at discharge 11.27 ± 0.82 mL vs 10.56 ± 0.82 mL, p < 0.01). The surgery induced an increase in AST and in total bilirubin regardless of the assigned group, and the treatment induced no change in liver function.

CONCLUSIONS

Our data suggest that EGCG plus vitamin D, and DCI could represent a safe option for women with UF scheduled for laparoscopic myomectomy, improving surgical outcomes without affecting liver functionality.

<sc>d</sc>-Chiro-Inositol in Clinical Practice: A Perspective from the Experts Group on Inositol in Basic and Clinical Research (EGOI)

BACKGROUND

d-Chiro-inositol is a natural molecule that, in association with its well-studied isomer myo-inositol, may play a role in treating various metabolic and gynecological disorders.

OBJECTIVES

This perspective seeks to explore the mechanisms and functions of d-chiro-inositol, laying the foundations to discuss its use in clinical practice, across dysmetabolism, obesity, and hormonal dysregulation.

METHODS

A narrative review of all the relevant papers known to the authors was conducted.

OUTCOME

d-Chiro-inositol acts through a variety of mechanisms, acting as an insulin sensitizer, inhibiting the transcription of aromatase, in addition to modulating white adipose tissue/brown adipose tissue transdifferentiation. These different modes of action have potential applications in a variety of therapeutic fields, including PCOS, dysmetabolism, obesity, hypoestrogenic/hyperandrogenic disorders, and bone health.

CONCLUSIONS

d-Chiro-inositol mode of action has been studied in detail in recent years, resulting in a clear differentiation between d-chiro-inositol and its isomer myo-inositol. The insulin-sensitizing activities of d-chiro-inositol are well understood; however, its potential applications in other fields, in particular obesity and hyperestrogenic/hypoandrogenic disorders in men and women, represent promising avenues of research that require further clinical study.

Analysis and comparison of bioactive phytochemical composition and antibacterial property of two Ethiopian indigenous medicinal plants

Indigenous medicinal plants with naturally inherited antimicrobial properties are promising sources of antimicrobial agents. Two indigenous Ethiopian traditional medicinal plants (Rhamnus prinoide and Croton macrostachyus) extracted using different solvents and the yield percentage, phytochemical analysis and antimicrobial activity of the plant extracts were examined and compared. The results of this study revealed that Rhamnus prinoide leaf extract using aqueous methanol/ethanol (1 : 1) had the highest yield (15.12 %), a minimum inhibitory concentration of 0.625 mg/mL, and a minimum bactericidal concentration of 10 mg/mL against S. aureus. Croton macrostachyus leaves showed a yield of 14.7 ±0.37 %, a minimum inhibitory concentration of 40 mg/mL, and a minimum bactericidal concentration of 40 mg/mL against S. aureus and E. coli. GC-MS analysis revealed that aqueous methanol/ethanol (1 : 1) of Rhamnus prinoide and Croton macrostachyus leaf extracts were composed of bioactive carbohydrates, flavonoid acid phenols, and terpenoids, while Croton macrostachyus extract contained primarily phytol (30.08 %). The presence of bioactive compounds confirms the traditional use of these plant leaves to treat various diseases, including wounds, leading to the conclusion that they could be applied to textiles for wound dressing in future studies.

D-Chiro-Inositol in Endometrial Hyperplasia: A Pilot Study

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.

Changes in the Carbohydrate Profile in Common Buckwheat (Fagopyrum esculentum Moench) Seedlings Induced by Cold Stress and Dehydration

Plant species are sensitive to stresses, especially at the seedling stage, and they respond to these conditions by making metabolic changes to counteract the negative effects of this. The objectives of this study were to determine carbohydrate profile in particular organs (roots, hypocotyl, and cotyledons) of common buckwheat seedlings and to verify whether carbohydrate accumulation is similar or not in the organs in response to cold stress and dehydration. Roots, hypocotyl, and cotyledons of common buckwheat seedlings have various saccharide compositions. The highest concentrations of cyclitols, raffinose, and stachyose were found in the hypocotyl, indicating that they may be transported from cotyledons, although this needs further studies. Accumulation of raffinose and stachyose is a strong indicator of the response of all buckwheat organs to introduced cold stress. Besides, cold conditions reduced d-chiro-inositol content, but did not affect d-pinitol level. Enhanced accumulation of raffinose and stachyose were also a distinct response of all organs against dehydration at ambient temperature. The process causes also a large decrease in the content of d-pinitol in buckwheat hypocotyl, which may indicate its transformation to d-chiro-inositol whose content increased at that time. In general, the sucrose and its galactosides in hypocotyl tissues were subject to the highest changes to the applied cold and dehydration conditions compared to the cotyledons and roots. This may indicate tissue differences in the functioning of the protective system(s) against such threats.

D-Chiro-Inositol and Myo-Inositol Induce WAT/BAT Trans-Differentiation in Two Different Human Adipocyte Models (SGBS and LiSa-2)

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.

Neurobiology and Applications of Inositol in Psychiatry: A Narrative Review

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

Long-Lasting Therapies with High Doses of D-chiro-inositol: The Downside

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.

Inositol Derivatives with Anti-Inflammatory Activity from Leaves of Solanum capsicoides Allioni

Eight new inositol derivatives, solsurinositols A-H (1-8), were isolated from the 70% EtOH extract of the leaves of Solanum capsicoides Allioni. Careful isolation by silica gel column chromatography followed by preparative high-performance liquid chromatography (HPLC) allowed us to obtain analytically pure compounds 1-8. They shared the same relative stereochemistry on the ring but have different acyl groups attached to various hydroxyl groups. This was the first time that inositol derivatives have been isolated from this plant. The chemical structures of compounds 1-8 were characterized by extensive 1D nuclear magnetic resonance (NMR) and 2D NMR and mass analyses. Meanwhile, the in vitro anti-inflammatory activity of all compounds was determined using lipopolysaccharide (LPS)-induced BV2 microglia, and among the isolates, compounds 5 (IC₅₀ = 11.21 ± 0.14 µM) and 7 (IC₅₀ = 14.5 ± 1.22 µM) were shown to have potential anti-inflammatory activity.

The Translational Role of miRNA in Polycystic Ovary Syndrome: From Bench to Bedside—A Systematic Literature Review

MicroRNAs (miRNAs) are small, non-coding RNAs that are essential for the regulation of post-transcriptional gene expression during tissue development and differentiation. They are involved in the regulation of manifold metabolic and hormonal processes and, within the female reproductive tract, in oocyte maturation and folliculogenesis. Altered miRNA levels have been observed in oncological and inflammatory diseases, diabetes or polycystic ovary syndrome (PCOS). Therefore, miRNAs are proving to be promising potential biomarkers. In women with PCOS, circulating miRNAs can be obtained from whole blood, serum, plasma, urine, and follicular fluid. Our systematic review summarizes data from 2010–2021 on miRNA expression in granulosa and theca cells; the relationship between miRNAs, hormonal changes, glucose and lipid metabolism in women with PCOS; and the potential role of altered miRNAs in fertility (oocyte quality) in PCOS. Furthermore, we discuss miRNAs as a potential therapeutic target in PCOS and as a diagnostic marker for PCOS.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Novel Chemical and Biological Insights of Inositol Derivatives in Mediterranean Plants

Inositols (Ins) are natural compounds largely widespread in plants and animals. Bio-sinthetically they derive from sugars, possessing a molecular structure very similar to the simple sugars, and this aspect concurs to define them as primary metabolites, even though it is much more correct to place them at the boundary between primary and secondary metabolites. This dichotomy is well represented by the fact that as primary metabolites they are essential cellular components in the form of phospholipid derivatives, while as secondary metabolites they are involved in a plethora of signaling pathways playing an important role in the surviving of living organisms. myo-Inositol is the most important and widespread compound of this family, it derives directly from d-glucose, and all known inositols, including stereoisomers and derivatives, are the results of metabolic processes on this unique molecule. In this review, we report the new insights of these compounds and their derivatives concerning their occurrence in Nature with a particular emphasis on the plant of the Mediterranean area, as well as the new developments about their biological effectiveness.