Adipokine concentrations in nonobese women: a study of reproductive aging, body mass index, and menstrual cycle effects.

Objective: To explore the influence of reproductive aging, body mass index (BMI), and the menstrual cycle on adiponectin (AD) and leptin concentrations.

Design: Cross-sectional comparison in age- and BMI-matched nonobese volunteers with regular cycles (CO, n = 19) or in early postmenopause (EPM, n = 19), aged 40-52 years, and a young cycling group (CY, n = 21), aged 20-30 years.

Measures: Sex steroids, fasting AD, leptin, insulin, glucose, AD/leptin (A/L) ratio, and insulin resistance (IR) by homeostasis model assessment (HOMA-IR).

Black cohosh has central opioid activity in postmenopausal women: evidence from naloxone blockade and positron emission tomography neuroimaging.

Objective: To test whether black cohosh (BC) exhibits an action on the central endogenous opioid system in postmenopausal women.

Design: This was a mechanistic study conducted in the same individuals of luteinizing hormone pulsatility with a saline/naloxone challenge (n = 6) and positron emission tomography with [C]carfentanil, a selective micro-opioid receptor radioligand (n = 5), before and after 12 weeks of unblinded treatment with a popular BC daily supplement.

Results: BC treatment for 12 weeks at a standard dose (Remifemin, 40 mg/day) had no effect on spontaneous luteinizing hormone pulsatility or estrogen concentrations.

Differential effects of aging on activin A and its binding protein, follistatin, across the menopause transition.

To assess the involvement of ovarian-derived regulatory proteins in FSH modulation, we compared FSH, inhibin A, inhibin B, activin A, and follistatin (FS) in 79 women from the following five groups: young cycling, older cycling, perimenopause (PERI), spontaneous menopause (PM), and surgical menopause receiving estrogen (OVX+ET). Although inhibin B varied as expected by ovarian function, no group differences were observed in activin A, barring a tendency for an increase in PERI, while FS 288 was lower in the PERI, PM, and OVX+ET groups and negatively correlated with advancing age.

Differential associations for menopause and age in measures of vitamin K, osteocalcin, and bone density: a cross-sectional exploratory study in healthy volunteers.

Objective: To distinguish the effects of midlife aging from early postmenopause on vitamin K measures, bone formation biomarkers, and bone density.

Design: Cycling older volunteers (CO; 40-52 years, n = 19) were compared to cycling young (CY; 20-30 years, n = 21) and untreated, age-matched women in the early postmenopause years (EPM; 40-52 years, mean years PM = 2.8 +/- 0.

Midlife women's responses to a hospital sleep challenge: aging and menopause effects on sleep architecture.

Objective: To distinguish aging from menopause effects on sleep architecture, we studied an episode of disturbed hospital sleep in asymptomatic midlife women during the follicular phase of an ovulatory cycle and three control groups differing by age or menopause status.

Methods: Fifty-one studies were conducted in four groups of volunteers: young cycling (YC, 20-30 years, n = 14), older cycling (OC, 40-50 years, n = 15), ovariectomized receiving estrogen therapy (OVX, 40-50 years, n = 12), and spontaneously postmenopausal (PM, 40-50 years, n = 10). Subjects were admitted to the University Hospital General Clinical Research Center (GCRC) for a first-night sleep study conducted during a 24-hour, frequent blood sampling protocol.