COL1A1 and obesity due to melanocortin 4 receptor deficiency: Obesity robustly induced transcription of fibrotic genes in both subcutaneous white AT (scWAT) and visceral white AT (vWAT), including Col1a1, Col6a1, and Mmp2 (Fig. 1a and Supplementary Fig. 1a), consistent with RNAseq analysis of adipocytes that acquire a fibroblast-like transcriptional signature in response to a HFD feeding23.