TNF and obesity due to melanocortin 4 receptor deficiency: Although the levels of mRNAs encoding the pro-inflammatory factors TNF-α and MCP-1 were somewhat higher in the renal tissues of HFD-fed mice than of SFD-fed 12/15-LOKO mice, the differences were not statistically significantly, indicating that 12/15-LO knockout affects the overexpression of obesity-associated inflammatory factors such as TNF-α in the kidneys.