The RolE oF Androgen Excess in MUscle Energy MetaboLism in Women With PolyCystic Ovary Syndrome (The REFUEL PCOS) Study 1

Brief Summary

Detailed Description

Polycystic ovary syndrome (PCOS) is a lifelong metabolic disorder, affecting 10-13% of all women, and is associated with a major healthcare and economic burden, estimated at $8 billion annually the US in 2020 (1, 2). Traditionally considered a reproductive disorder only, it is now increasingly clear that PCOS is associated with severe metabolic health consequences across the entire life course of women (3, 4). There is a two-fold increased risk of type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease, as well as emerging evidence of increased incidence of cardiovascular disease (CVD) (5-7). There are no disease-specific therapies to mitigate or treat metabolic risk in women with PCOS. This is consistently highlighted as the priority concern amongst PCOS patient advocacy groups. Androgen excess is a cardinal feature of PCOS and circulating androgen burden is closely correlated with metabolic complications (5, 8-12). In women with PCOS, the risk of developing metabolic dysfunction is above that conferred by simple obesity, suggesting that androgen excess is a key player; however, a distinct mechanistic role for androgens in this process remains to be elucidated (13, 14). Androgen excess is associated with metabolically deleterious visceral fat accumulation and circulating testosterone levels correlate directly with the risk of T2DM and NAFLD. Muscle is a critical metabolic target tissue that plays a central role in energy metabolism through processes such as glucose uptake and oxidation, as well as oxidation of fatty acids to generate ATP in the mitochondria (15). Recent mechanistic data have shown that androgen excess is associated with changes in the transcriptional profile of skeletal muscle genes linked with metabolism and energy balance (15-17). Therefore, skeletal muscle is likely to represent an important site of crosstalk between androgen excess, disturbances in energy metabolism and risk of metabolic disease in PCOS. Defective skeletal muscle glucose uptake is a key early step in the pathogenesis of insulin resistance in PCOS, and an early predictor of progression to overt type 2 diabetes mellitus. Impaired mitochondrial oxidation of free fatty acids in skeletal muscle, as well as other disturbances in skeletal muscle mitochondrial function such as oxidative phosphorylation, are increasingly implicated in the pathogenesis of metabolic disease such as T2DM (18-20). Abnormalities in skeletal muscle mitochondrial function have also been identified in small scale studies in women with PCOS, and were associated with impaired fatty acid oxidation, weight gain and an increased risk of diabetes (21, 22). The investigators hypothesise that androgen-mediated disturbances in skeletal muscle energy balance play a major role in the pathogenesis of metabolic disease in women with PCOS. The investigators propose to test this using cross-sectional and interventional approaches utilising state-of-the-art metabolic phenotyping tools.

Primary Outcomes

Secondary Outcomes

• Proteomic profiling of skeletal muscle biopsies will be integrated with serum steroid and non-targeted metabolome data to delineate the relationship between androgens and skeletal muscle energy metabolism in women(2.5 years)