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

Intensive Medical Nutrition Therapy Alone or with Added Metformin to Prevent Gestational Diabetes Mellitus among High-Risk Mexican Women: A Randomized Clinical Trial

The aim of this study was to examine the efficacy of intensive medical nutrition therapy (MNT) plus metformin in preventing gestational diabetes mellitus (GDM) among high-risk Mexican women. An open-label randomized clinical trial was conducted. Inclusion criteria were pregnant women with three or more GDM risk factors: Latino ethnic group, maternal age >35 years, body mass index >25 kg/m2, insulin resistance, and a history of previous GDM, prediabetes, a macrosomic neonate, polycystic ovarian syndrome, or a first-degree relative with type 2 diabetes. Women before 15 weeks of gestation were assigned to group 1 (n = 45): intensive MNT-plus metformin (850 mg twice/day) or group 2 (n = 45): intensive MNT without metformin. Intensive MNT included individual dietary counseling, with ≤50% of total energy from high carbohydrates. The primary outcome was the GDM incidence according to the International Association of Diabetes Pregnancy Study Groups criteria. There were no significant differences in baseline characteristics and adverse perinatal outcomes between the groups. The GDM incidence was n = 11 (24.4%) in the MNT plus metformin group versus n = 7 (15.5%) in the MNT without metformin group: p = 0.42 (RR: 1.57 [95% CI: 0.67–3.68]). There is no benefit in adding metformin to intensive MNT to prevent GDM among high-risk Mexican women. Clinical trials registration: NCT01675310.

Placental Inositol Reduced in Gestational Diabetes as Glucose Alters Inositol Transporters and IMPA1 Enzyme Expression

CONTEXT

Perturbed inositol physiology in insulin-resistant conditions has led to proposals of inositol supplementation for gestational diabetes (GDM) prevention, but placental inositol biology is poorly understood.

OBJECTIVE

Investigate associations of maternal glycemia with placental inositol content, determine glucose effects on placental expression of inositol enzymes and transporters, and examine relations with birthweight.

DESIGN AND PARTICIPANTS

Case-control study of placentae from term singleton pregnancies (GDM n = 24, non-GDM n = 26), and culture of another 9 placentae in different concentrations of glucose and myo-inositol for 48 hours.

MAIN OUTCOME MEASURES

Placental inositol was quantified by the Megazyme assay. Relative expression of enzymes involved in myo-inositol metabolism and plasma membrane inositol transport was determined by quantitative RT-PCR and immunoblotting. Linear regression analyses were adjusted for maternal age, body mass index, ethnicity, gestational age, and sex.

RESULTS

Placental inositol content was 17% lower in GDM compared with non-GDM. Higher maternal mid-gestation glycemia were associated with lower placental inositol. Increasing fasting glycemia was associated with lower protein levels of the myo-inositol synthesis enzyme, IMPA1, and the inositol transporters, SLC5A11 and SLC2A13, the expression of which also correlated with placental inositol content. In vitro, higher glucose concentrations reduced IMPA1 and SLC5A11 mRNA expression. Increasing fasting glycemia positively associated with customized birthweight percentile as expected in cases with low placental inositol, but this association was attenuated with high placental inositol.

CONCLUSION

Glycemia-induced dysregulation of placental inositol synthesis and transport may be implicated in reduced placental inositol content in GDM, and this may in turn be permissive to accelerated fetal growth.

Male Equivalent Polycystic Ovarian Syndrome: Hormonal, Metabolic, and Clinical Aspects

Recent studies identified the presence of a male polycystic ovarian syndrome (PCOS), which mainly affects men whose female relatives are afflicted with PCOS, caused by genes responsible for the susceptibility of this syndrome in women. Similar hormonal, metabolic, and clinical alterations occurring in PCOS women have also been reported in their male relatives, suggesting a association between the male and female forms of the syndrome. Although the remarkable clinical manifestation of the male equivalent PCOS is diagnosed by the early-onset androgenetic alopecia, characterized by hair recession, pronounced hypertrichosis, insulin resistance, biochemical and hormonal abnormalities, the hormonal/metabolic profile is still controversial. Men affected by early-onset androgenetic alopecia (AGA) are at risk of developing hyperinsulinemia, insulin-resistance, dyslipidaemia, and cardiovascular diseases. However, there is no consensus on the association of male equivalent PCOS with hypertension and obesity. Moreover, reduced levels of sex hormone-binding globulin have been detected in these male patients, accompanied by increased free androgens. Conversely, literature reported lower concentrations of testosterone in male equivalent PCOS when compared with the normal range, indicating a crucial role for the conversion of cortical androgens. Finally, further studies are warranted to investigate a possible link among AGA, metabolic/hormonal alterations, and acne. Our study assessed the hormo- nal, metabolic and clinical aspects of male equivalent PCOS syndrome reported in the literature to evaluate similar and divergent elements involved in the female version of the syndrome.