American journal of physiology. Endocrinology and metabolism | 2019
Heat therapy improves glucose tolerance and adipose tissue insulin signaling in obese women with polycystic ovary syndrome.
Abstract
Polycystic Ovary Syndrome (PCOS) is associated with high rates of obesity and metabolic dysfunction. Repeated passive heat exposure (termed heat therapy ) is a novel lifestyle intervention for improving health in obese women with PCOS. The purpose of this study was to examine changes in metabolic function in obese women with PCOS following heat therapy. Eighteen age- and BMI-matched obese women with PCOS (Age: 27±1y, BMI 41.3±1.1 kg·m2) were assigned to heat therapy (HT) or time control (CON). HT subjects underwent 30 one-hour hot tub sessions over 8-10 weeks, while CON subjects completed all testing but did not undergo heat therapy. Before (Pre), at the mid-point (Mid), and following (Post) 8-10 weeks of heat therapy, metabolic health was assessed using a 2-hr oral glucose tolerance test, a subcutaneous abdominal fat biopsy (Pre-Post only), and other blood markers relating to metabolic function. HT subjects exhibited improved fasting glucose (Pre:105±3, Post:89±5mg/dL; p=0.001), glucose area under the curve (AUC; Pre: 18,698±1045, Post:16,987±1017mg/dL/min; p=0.028) and insulin AUC (Pre:126,924±11,730, Post: 91,233±14,429IU/L/min; p=0.012). Adipocyte insulin signaling (p-AKT at Ser473 with 1.2ng/mL insulin) increased in HT (Pre: 0.29±0.14, Post: 0.93±0.29AU, p=0.021). Additionally, serum testosterone declined in HT subjects (Pre:51±7, Post:34±4ng/d/L; p=0.033). No parameters changed over time in CON, and no change in BMI was observed in either group. HT substantially improved metabolic risk profile in obese women with PCOS. HT also reduced androgen excess and may improve PCOS symptomology.