Liberato Soranna

Individual effect of E2 and dydrogesterone on insulin sensitivity in post-menopausal women

The aim of this study was to evaluate the impact of a three-month continuous administration of oral E2, alone, or combined with 2 different dosages of dydrogesterone, on the glucose tolerance and insulin sensitivity in postmenopausal women. In a prospective placebocontrolled study, 43 normal weight and normoinsulinemic women were randomized to receive either 2 mg of oral 17β?E2 daily (group A), or 2 mg E2 daily plus 5 mg daily oral dydrogesterone, from day 14 to 28, in a sequentially combined regimen (group B), or 2 mg of E2 and 10 mg dydrogesterone in the same sequentially combined regimen (group C) or placebo for 12 weeks. An OGTT and a euglycemic hyperinsulinemic clamp were performed before and after treatment. Serum glucose and insulin concentrations were measured both in fasting conditions and after OGTT. C-peptide pancreatic secretion was tested only in fasting conditions. Total body glucose utilization (M), for insulin sensitivity evaluation, was determined in each subject. Postmenopausal women treated with unopposed 17β E2 (group A) showed a slight but statistically significant decrease of insulin sensitivity (p<0.05). A more marked deterioration of the same parameter was observed in the 2 groups treated with E2 plus dydrogesterone (group B and group C: p<0.01). Post hoc testing for the percent change from baseline indicated that group A significantly differed from group C (p<0.05) and all treated groups significantly differed from the placebo group (p<0.01). Finally, after treatment in group C, a significant reduction of insulin and an increase of glucose responses to OGTT (p<0.01) were observed. These results indicate that, in a short-term period, the use of 17β?E2 and overall 17β?E2 plus dydrogesterone, even with the reduction of insulin plasma levels, might cause a decrease in insulin sensitivity in normal weight and normoinsulinemic post-menopausal women.

Growth hormone administration normalizes the ovarian responsiveness to follicle-stimulating-hormone in the early stages of the follicular maturation in women with Down Syndrome

To investigate the sensitivity of ovary to follicle-stimulating hormone (FSH) during the early follicular phase of the human menstrual cycle in patients with Down Syndrome (DS) six post-menarchal patients with Down Syndrome and twelwe normoovulatory women were studied. Randomly, DS patients were submitted in two consecutive cycles to a treatment with GH (0.1 IU/Kg im) or saline for 3 days. Pure FSH (75 IU) was given iv at day 3 and plasma levels of LH, FSH, E2, Testosterone, DHEAS, Androstenedione, GH and IGF-I were assayed in samples collected for a period of 26h after the injection. Data were compared with those obtained from controls receiving pure FSH or saline. In control patients FSH injection increased E2 stimulated area under curve (AUC). This value was significantly greater than that found in DS patients, who exhibited an E2-stimulated AUC superimposable to saline treated controls. In DS GH plasma concentrations were significantly lower than in control group (p<0.05). The treatment with GH is able to normalize the ovarian response to FSH in DS patients at levels similar to those found in FSH treated controls. Moreover in GH treated cycles, both GH and IGF-I plasma concentrations were higher at time of FSH injection with respect to those found in the cycles where saline was given. These results indicate that the ovarian sensitivity to FSH in patients with DS is blunted. Lower GH plasma levels found in this group may in part account for this biological feature, since GH treatment is able to restore the ovarian response, probably via an increase of IGF-I plasma concentrations.

Naloxone decreases insulin secretion in hyperinsulinemic postmenopausal women and may positively affect hormone replacement therapy

OBJECTIVE To evaluate the influence of the opioid system on glyco-regulation in postmenopausal women before and after hormone replacement therapy (HRT). DESIGN Prospective nonrandomized clinical study. SETTING Academic research environment. PATIENT(S) Twenty-one healthy normo- or hyperinsulinemic postmenopausal women. INTERVENTION(S) Oral glucose tolerance test (OGTT) (saline study), OGTT with IV injection of naloxone (naloxone study), and hyperinsulinemic euglycemic clamp performed before treatment, after 12 weeks of estrogen replacement therapy (ERT), and after 12 additional weeks of estro-progestin combined therapy (i.e., HRT). MAIN OUTCOME MEASURE(S) Glucose, insulin, and c-peptide plasma levels assessed in fasting condition and during the two OGTTs (area under the curve [AUC]). Evaluation of fractional hepatic insulin extraction (FHIE) and peripheral sensitivity to insulin. RESULT(S) At baseline, there is a greater increase of the FHIE and a more significant reduction of the insulin AUC in the hyperinsulinemic patients during the naloxone study compared with the saline study. In these women, ERT enhanced the c-peptide AUC and improved the FHIE; naloxone infusion mainly increased these two parameters. HRT did not induce any further change. CONCLUSION(S) Endogenous opioid peptides are involved in the modulation of carbohydrate metabolism in menopause in hyperinsulinemic patients more than in other patients. The favorable changes of the glyco-insulinemic metabolism induced by HRT may be partially due to the induction of the opioidergic activity.