Decreased splenic mRNA expression levels of TNF-alpha and IL-6 in diet-induced obese animals.

Obesity could be considered as a systemic low-grade inflammatory condition affecting inflammation markers. Adipose tissue synthesizes cytokines whose degree of elevation may depend on the obesity status. Recently, new information is collected on the cross-talking between immune system and adipose tissue in obesity. We report hereby that tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) gene expression in spleen of diet-induced obese animals were markedly decreased (more than 50%) as a consequence of the high fat feeding during five weeks. Interestingly, a very significant negative correlation was found between splenic TNF-alpha mRNA levels and total fat pads (r = -0.806, p = 0.000). These findings support the hypothesis that TNF-alpha gene expression may follow different trends in obese animals adipocytes and splenocytes.