Therapeutics · Metabolic and Endocrine Agents

Evidence-Based and Patient-Oriented Inositol Treatment in Polycystic Ovary Syndrome: Changing the Perspective of the Disease

Laganà AS, Rossetti P, Sapia F, Chiofalo B, Buscema M, Valenti G, Rapisarda AMC, Vitale SG

Published August 25, 2017 International Journal of Endocrinology and Metabolism, 15(1), e43695
DOI 10.5812/ijem.43695 PMID 28835764 PMC PMC5554611
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RRM Academy Synopsis

Editorial argues inositol improves hormone and insulin signs in PCOS

The editorial argues that inositol improves hormone and insulin measures in PCOS. Italian researchers sum up studies in women with PCOS, now also called PMOS (polyendocrine metabolic ovarian syndrome). In their own cohort, they report lower male hormones and more regular cycles after treatment. They ask for bigger trials.

Key Findings

  • PCOS affects about 6% to 10% of women of reproductive age, the authors write. Insulin resistance and high insulin levels are common but not required for diagnosis.
  • In the authors' own large group of women with PCOS, 6 months of D-chiro-inositol with folic acid was followed by lower androgen measures, better insulin markers and more regular cycles.
  • A randomized trial the authors cite found that myo-inositol and D-chiro-inositol both improved ovarian function and metabolic profile. D-chiro-inositol most affected hyperandrogenism. Myo-inositol lowered insulin resistance more.
  • A recent trial found no significant difference between metformin and myo-inositol for BMI, insulin sensitivity or menstrual cycle. The latest Cochrane review gave no robust recommendation for a best treatment.

Interpretation

The paper is a short editorial. It is an expert opinion with no new data and no stated method for choosing studies. The results come from earlier reports, including the authors' own, and no effect sizes are given. The authors say hormone and metabolic changes improve ovulation, egg quality and pregnancy rate, but the editorial gives no pregnancy or birth figures. The authors ask for larger studies and for comparisons with other insulin sensitizers.

RRM Context

Restorative reproductive medicine looks for the hormone and metabolic drivers behind irregular cycles. Insulin resistance and excess androgens are two such drivers in PCOS. Restorative clinicians follow ovulation and pregnancy. The editorial leaves both unquantified. PCOS has several forms, so the call for trials by form fits a search for the cause in each woman.

Abstract

Polycystic ovary syndrome (PCOS)’s rate is about 6% to10% among the reproductive aged women; it is characterized by menstrual cycle irregularity with oligo-anovulation, hyperandrogenism, insulin resistance, and compensatory hyperinsulinemia. Despite the fact that the last two elements are present in a large percentage of PCOS women, they are not mandatory for the diagnosis; in order to explain the pathogenesis in these patients, it was supposed that ovarian theca cells got higher insulin sensitivity probably related to the mechanism of intracellular signalling transduction (1). Corroborating this view, it was previously demonstrated that diazoxid, which has the well-known effect of decreasing insulin levels, reduced hyperandrogenism in lean women affected by PCOS, even in the cases of normal insulin level and insulin sensitivity (2). Based on the detrimental role of insulin resistance, several insulin sensitizer drugs have been used to ameliorate PCOS symptoms and signs. Although metformin has represented the landmark of PCOS therapy in the recent past, to date several studies have tested the efficacy of Inositols, a carbocyclic polyols. Two stereoisomers, in particular Myo-inositol (MI) and D-Dhiro-inositol (DCI) showed a clinical efficacy and safety during PCOS. MI is converted in DCI by epimerase, an enzyme regulated also by insulin action. In the form of inositol-phosphoglycans (IPGs), they are involved in a non-classical insulin signalling cascade: insulin receptor is coupled by G-protein which can activate phospholipase, allowing the release of second messengers (DCI-glycan), which is able to stimulate pyruvate dehydrogenase and glycogen synthase activities, the enzyme involved in the oxidative and the non-oxidative glucose metabolism (3). On one hand, MI-IPG is able to inhibit cyclic adenosine monophosphate (cAMP) kinase and adenylyl cyclase, both involved in free fatty acid metabolism. On the other hand, DCI-IPG play a pivotal role during the binding of insulin to its receptor on cell membrane where it stimulates IPG release and starts signalling cascade. In addition, Inositols are incorporated in membrane phospholipids as phosphoinositides. Phosphatidylinositol 4, 5 bisphosphate (PtdIns-4, 5P) and phosphatidylinositol 4P (PtdIns-4P), in particular, are involved in the regulation of the cytoskeleton structure and in the regulation of cellular motility, which account also the beneficial effects of Inositol administration on sperm parameters. PtdIns-4, 5P plays a key role in controlling calcium-mediated intracellular signalling which is mandatory to address the oocytes maturation and fecundation (4).

Topics

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Related research

Therapeutics › Metabolic and Endocrine Agents › Insulin Sensitizing Agents · Reproductive Endocrinology › Ovarian Hormones › Androgens · Menstrual Cycle › Cycle Disorders › Ovulatory Disturbances
Antonio Simone Laganà, Benito Chiofalo, Massimo Buscema, Gaetano Valenti, Agnese Maria Chiara Rapisarda, Salvatore Giovanni Vitale, Paola Rossetti, Fabrizio Sapia
A Laganà, B Chiofalo, M Buscema, G Valenti, A Rapisarda, S Vitale, P Rossetti, F Sapia
PMID 28835764 28835764 DOI 10.5812/ijem.43695 10.5812/ijem.43695 Laganà et al. 2017, Laganà 2017

Cite this article

Laganà, A. S., Rossetti, P., Sapia, F., Chiofalo, B., Buscema, M., Valenti, G., Rapisarda, A. M. C., & Vitale, S. G. (2017). Evidence-Based and Patient-Oriented Inositol Treatment in Polycystic Ovary Syndrome: Changing the Perspective of the Disease. International journal of endocrinology and metabolism, 15(1), e43695. https://doi.org/10.5812/ijem.43695