TNF and obesity due to melanocortin 4 receptor deficiency: Aqueous extracts of E. ribes improved insulin resistance in a rat model with HFD-induced obesity, the possible mechanism of action being the downregulation of leptin, tumor necrosis factor-alpha (TNF-α), sterol regulatory element-binding proteins 1 gamma (SREBP1γ), and peroxisome proliferator-activated receptor gamma 2 (PPARγ2) gene expression.