Analysis of secreted peptidome from omental adipose tissue in polycystic ovarian syndrome patients

: Polycystic ovarian syndrome (PCOS) is a common endocrinopathy associated with increased risk of metabolic disorders. Prevalence of adiposity and obesity is greater in women suffering from PCOS. Moreover, adipose tissue dysfunction has been demonstrated in PCOS patients, particularly in abdominal adipose tissue. This dysfunction likely aggravates the metabolic and reproductive abnormalities. We used liquid chromatography-mass spectrometry to compare the peptides secreted from PCOS and non-PCOS abdominal adipose tissue. We detected 298 upregulated peptides and 31 downregulated peptides (absolute fold change ≥ 2 and p < 0.05). Twenty-nine peptides were only detected in the PCOS group, while 18 were only detected in the control group. In addition, we demonstrate that these cleavage products are not degradation products of the proteasome based on previous studies reported. Gene Ontology enrichment and pathway analysis were performed to study differentially secreted peptides through their precursor proteins. We identified 12 peptides from 10 precursor proteins associated with PCOS, and 6 peptide sequences were located in the functional domains of their corresponding precursor proteins. These results provide a deeper understanding of adipose tissue-derived peptides in PCOS for future functional studies.