Fish oil supplementation reverses the effect of cholesterol on apoptotic gene expression in smooth muscle cells

Abstract

BackgroundNutritional control of gene regulation guides the transformation of smooth muscle cells (SMC) into foam cells in atherosclerosis. Oxidative stress has been reported in areas of lipid accumulation, activating proliferation genes. Suppression of oxidative stress by antioxidant administration reduces this activation and the progression of lesions. We hypothesized that fish oil consumption may protect against atherosclerotic vascular disease. The study objective was to determine the effects of dietary cholesterol and fish-oil intake on the apoptotic pathways induced by 25-hydroxycholesterol (25-HC) in SMC cultures.MethodsAn in vivo/in vitro cell model was used, culturing SMC isolated from chicks exposed to an atherogenic cholesterol-rich diet with 5% of cholesterol (SMC-Ch) alone or followed by an anti-atherogenic fish oil-rich diet with 10% of menhaden oil (SMC-Ch-FO) and from chicks on standard diet (SMC-C). Cells were exposed to 25-HC, studying apoptosis levels by flow cytometry (Annexin V) and expressions of caspase-3, c-myc, and p53 genes by quantitative real-time reverse transcriptase-polymerase chain reaction. Results: Exposure to 25-HC produced apoptosis in all three SMC cultures, which was mediated by increases in caspase-3, c-myc, and p53 gene expression. Changes were more marked in SMC-Ch than in SMC-C, indicating that dietary cholesterol makes SMC more susceptible to 25-HC-mediated apoptosis. Expression of p53 gene was elevated in SMC-Ch-FO. This supports the proposition that endogenous levels of p53 protect SMC against apoptosis and possibly against the development of atherosclerosis. Fish oil attenuated the increase in c-myc levels observed in SMC-C and SMC-Ch, possibly through its influence on the expression of antioxidant genes.ConclusionReplacement of a cholesterol-rich diet with a fish oil-rich diet produces some reversal of the cholesterol-induced changes, increasing the resistance of SMC to apoptosis.

Polyunsaturated fatty acids ameliorate aging via redox-telomere-antioncogene axis

“…In contrast, to respond severe oxidative stress, p53 exhibits prooxidant activities and leads to cell death [ 41 ]. Therefore, it is not difficult to interpret the controversial data that n-3 PUFA may inhibit [ 42 , 43 ] or induce [ 44 , 45 ] p53 expression in both in vivo and in vitro experiments. However, none of these studies have addressed the effects of n-3 PUFA on p53 expression in an anti-aging view.…”

Cardiomyocyte apoptosis in ischaemia‐reperfusion due to the exogenous oxidants at the time of reperfusion

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The In Vitro, Ex Vivo, and In Vivo Effect of Edible Oils: A Review on Cell Interactions

“…Food processing, a crucial link between production and consumption within the food value chain, entails the conversion of raw materials into edible, safe, and organoleptically and culturally acceptable food products [ 3 ]. Ex vivo and in vitro biological studies highlight the significance of key sustainability indicators and impact evaluation when creating instruments to study how human cells interact with the constituents of edible oils [ 1 , 4 , 5 , 6 , 7 ]. These methods offer less expensive means to survey food components and reduce the probability of surprises when clinical trials are performed to elucidate their health benefits.…”

“…These methods offer less expensive means to survey food components and reduce the probability of surprises when clinical trials are performed to elucidate their health benefits. For the aforementioned reasons, in vitro assays for food applications are performed in human cells and mice models, such as hepatocytes [ 4 , 8 ], whole blood cells [ 5 , 9 ], neural cells [ 10 , 11 ], and various other cell types (keratinocytes and smooth muscle cells) [ 6 , 7 ] and mice/rat models, such as C57BL/6, Swiss strain mice, and Sprague Dawley rats [ 12 , 13 , 14 ], etc., to investigate edible oils’ “natural” health effects.…”