Obesity is a significant metabolic disorder associated with excessive fat accumu-lation and insulin resistance. In this study, we explored a gene therapy approach to treat obesity in agouti mice using adeno-associated viruses (AAVs) carrying PRDM16, FoxP4, or Follistatin (FST) genes, which are known to promote the browning of white adipose tissue. Mice treated with AAVs encoding PRDM16, FoxP4, or FST genes showed a reduction in body weight (9-12%) within the first three weeks after admin-istration, compared to control groups. Lipidomic analysis of adipose tissue revealed a dramatic reduction in triacylglycerol (TAG) species with low carbon number (40-54 acyl carbones) in treated mice.