Grape-seed procyanidins prevent low-grade inflammation by modulating cytokine expression in rats fed a high-fat diet

As expected, rats fed the HF diet show an enhanced production of CRP. Our results demonstrate that the HFPE diet decreases rat plasma CRP levels but not IL-6 levels. The decrease in plasma CRP in HFPE rats is related to a down-regulation of CRP mRNA expression in the liver and mesenteric WAT. We have also shown a decrease in the expression of the proinflammatory cytokines TNF-α and IL-6 in the mesenteric WAT. In contrast, adiponectin mRNA is increased in this tissue due to the procyanidin treatment. As previously reported, CRP plasma levels correlate positively with its expression in the mesenteric WAT, suggesting that procyanidin extract (PE) modulates CRP at the synthesis level. CRP plasma levels also correlate positively with body weight. As expected, body weight is associated with the adiposity index. Also, TNF-α expression and IL-6 expression have a strong positive correlation. In contrast, the expression of the anti-inflammatory cytokine adiponectin correlates negatively with the expression of TNF-α and IL-6 in the mesenteric WAT.