Ginger and turmeric lipid-solubles attenuate heated oil-induced hepatic inflammation via the downregulation of NF-kB in rats.

Purpose: Reusing deep-fried vegetable oils multiple times is a common practice to save costs, and their chronic consumption may cause hepatic dysfunction. In this investigation, we assessed the modulatory effects of ginger and turmeric lipid-solubles that may migrate to oils during heating on the hepatic inflammatory response in rats.

Methods: Male Wistar rats were fed with; 1) control {native canola (N-CNO) or native sunflower (N-SFO)} oil, 2) heated (heated canola {(H-CNO) or heated sunflower (H-SFO)} oil, and 3) heated oil with ginger or turmeric {heated canola with ginger (H-CNO + GI) or heated canola oil with turmeric (H-CNO + TU), heated sunflower oil with ginger (H-SFO + GI) or heated sunflower oil with turmeric (H-SFO + TU)} for 120 days. Hepatic inflammatory response comprising eicosanoids, cytokines, and NF-kB were assessed.

Results: Compared to respective controls, feeding heated oils significantly (p < 0.05); 1) increased eicosanoids (PGE, LTB, and LTC) and cytokines (TNF-α, MCP-1, IL-1β, and IL-6), 2) increased nuclear translocation of NF-kB in the liver, and 3) increased the hepatic expression of 5-LOX, COX-2, BLT-1, and EP-4. However, feeding oils heated with ginger or turmeric positively countered the changes induced by consumption of heated oils.

Conclusions: Consumption of repeatedly heated oil may cause hepatic dysfunction by inducing inflammatory stress through NF-kB upregulation. Lipid-solubles from ginger and turmeric that may migrate to oil during heating prevent the hepatic inflammatory response triggered by heated oils in rats.