Effects of Graded Levels of Dietary Casein and Corn Oil on Total Cholesterol and Triacylglycerol in Plasma and Liver of Rats.

Abstract

SummaryWith the intention of examining the effects of dietary protein and oil levels on total cholesterol (T-CHOL) and triacylglycerol (TG) concentrations in the plasma and liver, male Wistar rats, weighing about 170g, were fed diets containing graded levels of casein and corn oil for 2 wk. At the 5, 20, and 30% levels of dietary corn oil, plasma T-CHOL con centrations were generally enhanced in proportion to the rise of dietary casein level, but plasma TG contents were scarcely influenced by the level. At the 8 to 3 5% casein levels, plasma T-CHOL and TG concentrations were the highest at the 5% corn oil level, followed in order by the 20 and 30% levels of oil. At the 5 and 20% oil levels, hepatic T-CHOL contents were hardly changed at the 8 to 30% casein levels, but enhanced at the 35% casein level. At the 30% oil level, the T-CHOL contents tended to be changed proportionally to casein levels. At all levels of casein, hepatic T-CHOL contents tended to be relatively high at the 30% corn oil, middle at the 20% oil, and low at the 5% one. At each corn oil level, TG contents in the liver tended to be elevated at the 8 to 15% casein levels and highly preserved at the 15 to 25% ones. Then, the raised TG contents declined at the 5 and 20% levels of corn oil and re mained constant at the 30% oil. At each casein level, the contents of hepatic TG were gener ally high at the 30% oil level, followed in order by the 20 and 5% oil levels. These results in dicated that plasma and liver T-CHOL concentrations were proportionately enhaaced by the increase in casein level, and plasma TG contents were hardly affected by the level and he patic TG ones were lowered by relatively lower or higher casein level, and the rise in corn oil level generally reduced plasma T-CHOL and TG concentrations, but raised hepatic ones.

Short‐ and Long‐term Effects of Corn Oil on Serum Lipid and Lipoprotein and Visceral Abdominal Fat Pad Parameters of Rats

“…Furthermore, LDL‐C values showed an increase in both short‐term (15%) and long‐term (77%) studies (Table 1). In agreement with our findings, Takenchi et al . (2000) have shown that 2‐week feeding of rats on a diet incorporated with 5–30% corn oil had no effect on plasma TAG levels despite an increase on serum TC levels.…”

“…2003). For example, Takenchi et al . (2000) reported lipoprotein disorders as a result of feeding rats with corn oil.…”

“…However, there is mounting evidence that corn oil has many deleterious effects in rats (Sadi 1996;Jang et al 2003), other animal models (Vesselinovitch et al 1974) and humans (Petersen et al 2002;Pedersen et al 2003). For example, Takenchi et al (2000) reported lipoprotein disorders as a result of feeding rats with corn oil. In the rhesus monkey, a diet high in corn oil caused the development of hypercholesterolemia and atherogenesis; however, in this case, corn oil had no effect on the abdominal fat pad accumulation (Vesselinovitch et al 1974).…”

The Influence of Different Fat Sources on Steatohepatitis and Fibrosis Development in the Western Diet Mouse Model of Non-alcoholic Steatohepatitis (NASH)

“…Bohm et al (2013) postulated in 2013 that food derived peroxidized fatty acids such as linoleic acid included in WD with corn oil increases hepatic lipid peroxidation and influences immune cells and other pro-inflammatory stimuli that trigger hepatic damage. These findings were corroborated by Takeuchi et al (2000) and Slim et al (1996); finding that corn oil supplementation increased hepatic cholesterol and TG levels and activated the oxidative stress response. On the contrary Si et al (2014) showed 1 year later that a high corn oil diet improved health and longevity in mice by lowering serum lipid levels and decreasing the expression of pro-inflammatory cytokines such as IL-6, IL-1β or MCP-1.…”