Ginger and turmeric lipid-solubles attenuate heated oil-induced cardio-hepatic oxidative stress via the up-regulation of nuclear factor erythroid 2-related factor 2 and decrease blood pressure in rats.

Deep-fried vegetable oils are reused multiple times to save costs, and their chronic consumption may cause organ dysfunction. In this study, we assessed the modulatory effects of lipid-solubles from ginger and turmeric that may migrate to oils during heating, on the cardio-hepatic antioxidant defence response and blood pressure in rats. Male Wistar rats were fed with: (1) control (native rapeseed (N-CNO) or native sunflower (N-SFO)) oil, (2) heated (heated rapeseed (H-CNO) or heated sunflower (H-SFO)) oil and (3) heated oil with ginger or turmeric (heated rapeseed oil with ginger (H-CNO + GI) or heated rapeseed 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 d. Oxidative stress (OS) markers, antioxidant enzymes, nitric oxide synthase-2 (NOS-2), intercellular adhesion molecule-1 (ICAM-1), nuclear factor erythroid 2-related factor 2 (NRF-2), markers of hepatic and cardiac function and blood pressure were assessed. Feeding heated oils (H-CNO or H-SFO) (1) increased OS markers, NOS-2 and ICAM-1 expression; (2) decreased antioxidant enzyme activity and NRF-2 level; (3) increased marker enzymes of hepatic and cardiac function and (4) increased systolic and diastolic blood pressure significantly (P < 0·05), when compared with respective native oils (N-CNO or N-SFO). However, feeding oils heated with ginger or turmeric positively countered the changes induced by heated oils. Consumption of repeatedly heated oil causes cardio-hepatic dysfunction by inducing OS through NRF-2 down-regulation. Lipid-solubles from ginger and turmeric that may migrate to oil during heating prevent the oxidative stress and blood pressure triggered by heated oils in rats.