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Hyperandrogenism and inflammation are related in polycystic ovary syndrome (PCOS). Hyperandrogenemia can induce inflammation in reproductive-age women, but the mechanism for this phenomenon is unclear.We examined the in vivo and in vitro effects of hyperandrogenism on mononuclear cell (MNC)-derived androgen receptor (AR) status and TNFα release.This study combined a randomized, controlled, double-blind protocol with laboratory-based cell culture experiments.This work was performed in an academic medical center.Lean, healthy, reproductive-age women were treated with 130 mg of dehydroepiandrosterone (DHEA) or placebo (n = 8 subjects each) for 5 days and also provided untreated fasting blood samples (n = 12 subjects) for cell culture experiments.AR mRNA content and TNFα release were measured before and after DHEA administration in the fasting state and 2 hours after glucose ingestion. TNFα release in the fasting state was also measured in cultured MNCs exposed to androgens with or without flutamide preincubation.At baseline, subjects receiving DHEA or placebo exhibited no significant difference in androgens and TNFα release from MNCs before and after glucose ingestion. Compared with placebo, DHEA administration raised levels of T, androstenedione, and DHEA sulfate, and increased MNC-derived AR mRNA content and TNFα release in the fasting state and in response to glucose ingestion. Compared with MNC exposure to baseline concentrations of DHEA (175 ng/dL) or T (50 ng/dL), the absolute change in TNFα release increased after exposure to T concentrations of 125 and 250 ng/dL and a DHEA concentration of 1750 ng/dL. Preincubation with flutamide reduced the TNFα response by ≥ 60% across all T concentrations.Androgen excess in vivo and in vitro comparable to what is present in PCOS increases TNFα release from MNCs of lean healthy reproductive-age women in a receptor-dependent fashion. Hyperandrogenemia activates and sensitizes MNCs to glucose in this population.

Oxidative stress induced by reactive oxygen species (ROS) is involved in the development of pancreatic β-cell dysfunction.We determined the relationship between mononuclear cell (MNC)-derived ROS generation and p47phox protein content in response to glucose ingestion and β-cell function in women with polycystic ovary syndrome (PCOS).This was a cross-sectional study.This study was conducted at an academic medical center.Twenty-nine normoglycemic women with PCOS (13 lean, 16 obese) and 25 ovulatory controls (16 lean, 9 obese) underwent a 3-h 75-g oral glucose tolerance test (OGTT).Pancreatic β-cell function was calculated as glucose-stimulated insulin secretion (insulin/glucose area under the curve0-30 min; GSIS)×Matsuda index-derived insulin sensitivity (ISOGTT). ROS generation was measured by chemiluminescence, and p47phox protein was quantified by Western blotting in MNC isolated from blood samples obtained at 0 and 2 hours of the OGTT.Compared with controls, women with PCOS exhibited a higher percent change from baseline in ROS generation and p47phox protein in conjunction with greater GSIS and a tendency toward lower β-cell function. Lean women with PCOS exhibited a greater percent change from baseline in ROS generation and p47phox protein yet had similar GSIS responses compared with lean controls despite having lower ISOGTT. For the combined groups, β-cell function was inversely related to ROS generation and p47phox protein. GSIS was directly related to body mass index, central obesity, and circulating androgens.In normoglycemic women, obesity plays a role in exaggerating GSIS. However, MNC-derived oxidative stress is independent of obesity and may contribute to the decline in β-cell function in women with PCOS.

Inflammation and excess abdominal adiposity (AA) are often present in normal-weight women with polycystic ovary syndrome (PCOS).We determined the effects of hyperglycemia on nuclear factor-κB (NFκB) activation in mononuclear cells (MNC) of normal-weight women with PCOS with and without excess AA.This was a prospective controlled study.The study was conducted at an academic medical center.Fifteen normal-weight, reproductive-age women with PCOS (seven normal AA, eight excess AA) and 16 body composition-matched controls (eight normal AA, eight excess AA) participated in the study.Body composition was measured by dual-energy absorptiometry. Insulin sensitivity was derived from an oral glucose tolerance test (IS(OGTT)). Activated NFκB and the protein content of p65 and inhibitory-κB were quantified from MNC, and TNFα and C-reactive protein (CRP) were measured in plasma obtained from blood drawn while fasting and 2 h after glucose ingestion.Compared with controls, both PCOS groups exhibited lower IS(OGTT), increases in activated NFκB and p65 protein, and decreases in inhibitory-κB protein. Compared with women with PCOS with excess AA, those with normal AA exhibited higher testosterone levels and lower TNFα and CRP levels. For the combined groups, the percent change in NFκB activation was negatively correlated with IS(OGTT) and positively correlated with androgens. TNFα and CRP were positively correlated with abdominal fat.In normal-weight women with PCOS, the inflammatory response to glucose ingestion is independent of excess AA. Circulating MNC and excess AA are separate and unique sources of inflammation in this population.

Our objective was to determine whether exenatide exerts an antiinflammatory effect.Twenty-four patients were prospectively randomized to be injected sc with either exenatide 10 μg twice daily [n = 12; mean age = 56 ± 3 yr; mean body mass index = 39.8 ± 2 kg/m(2); mean glycosylated hemoglobin (HbA1c) = 8.6 ± 0.4%] or placebo twice daily (n = 12; mean age = 54 ± 4 yr; mean body mass index = 39.1 ± 1.6 kg/m(2); mean HbA1c = 8.5 ± 0.3%) for 12 wk. Fasting blood samples were obtained at 0, 3, 6, and 12 wk. Blood samples were also collected for up to 6 h after a single dose of exenatide (5 μg) or placebo.Fasting blood glucose fell from 139 ± 17 to 110 ± 9 mg/dl, HbA1c from 8.6 ± 0.4 to 7.4 ± 0.5% (P0.05), and free fatty acids by 21 ± 5% from baseline (P0.05) with exenatide. There was no weight loss. There was a significant reduction in reactive oxygen species generation and nuclear factor-κB binding by 22 ± 9 and 26 ± 7%, respectively, and the mRNA expression of TNFα, IL-1β, JNK-1, TLR-2, TLR-4, and SOCS-3 in mononuclear cells by 31 ± 12, 22 ± 10, 20 ± 11, 22 ± 9, 16 ± 7, and 31 ± 10%, respectively (P0.05 for all) after 12 wk of exenatide. After a single injection of exenatide, there was a reduction by 20 ± 7% in free fatty acids, 19 ± 7% in reactive oxygen species generation, 39 ± 11% in nuclear factor-κB binding, 18 ± 9% in TNFα expression, 26 ± 7% in IL-1β expression, 18 ± 7% in JNK-1 expression, 24 ± 12% in TLR-4 expression, and 23 ± 11% in SOCS-3 expression (P0.05 for all). The plasma concentrations of monocyte chemoattractant protein-1, matrix metalloproteinase-9, serum amyloid A, and IL-6 were suppressed after 12 wk exenatide treatment by 15 ± 7, 20 ± 11, 16 ± 7, and 22 ± 12%, respectively (P0.05 for all).Exenatide exerts a rapid antiinflammatory effect at the cellular and molecular level. This may contribute to a potentially beneficial antiatherogenic effect. This effect was independent of weight loss.