Evaluating the appropriate oral lipid tolerance test model for investigating plasma triglyceride elevation in mice

Abstract

The oral lipid tolerance test (OLTT) has been known to assess intestinal fat metabolism and whole-body lipid metabolism, but rodent models for OLTT are not yet established. Differences in OLTT methodology preclude the generation of definitive results, which may cause some confusion about the anti-hypertriglyceridemia effects of the test materials. To standardize and generate more appropriate methodology for the OLTT, we examined the effects of mice strain, dietary lipid sources, fasting period, and gender on lipid-induced hypertriglyceridemia in mice. First, lipid-induced hypertriglyceridemia was more strongly observed in male ddY mice than in C57BL/6N or ICR mice. Second, the administration of olive and soybean oils remarkably represented lipid-induced hypertriglyceridemia. Third, fasting period before the OLTT largely affected the plasma triglyceride elevation. Fasting for 12 h, but less than 48 h, provoked lipid-induced hypertriglyceridemia. Fourth, we explored the suppressive effects of epigallocatechin gallate (EGCG), a green tea polyphenol, on lipid-induced hypertriglyceridemia. The administration of 100 mg/kg of EGCG suppressed lipid-induced hypertriglyceridemia and intestinal lipase activity. Fifth, EGCG-induced suppressive effects were observed after lipid-induced hypertriglyceridemia was observed in male mice, but not in female mice. Lastly, lipid-induced hypertriglyceridemia could be more effectively induced in mice fed a high-fat diet for 1 week before the OLTT. These findings indicate that male ddY mice after 12 h fasting displayed marked lipid-induced hypertriglyceridemia in response to soybean oil. Hence, the defined experiment condition may be a more appropriate OLTT model for evaluating lipid-induced hypertriglyceridemia.

Dominant-negative HNF1α mutant promotes liver steatosis and inflammation by regulating hepatic complement factor D

“… 46 It is reported that ASP, which constitutes the predominant form of circulating C3a, can substantially stimulate the TG synthesis and glucose transport in adipose tissue. 47 , 48 Besides, the C3a and ASP are closely related to the development of NAFLD and hepatic inflammation. 25 , 49 In agreement with these studies, the concentrations of serum CFD and its direct cleavage product C3a increased in h HNF1A mut/- mice.…”

Agaricus bisporus Extract Exerts an Anti-Obesity Effect in High-Fat Diet-Induced Obese C57BL/6N Mice by Inhibiting Pancreatic Lipase-Mediated Fat Absorption

“…Based on previous clinical trials [19] and pancreatic lipase activity tests, it would be assumed that the consumption of ABE is likely to induce fewer adverse effects when compared to direct inhibitory agents like orlistat. Additionally, we assessed the fat trapping ability of ABE in vivo using an oral lipid tolerance test (OLTT), a standardized method to evaluate the body's ability to digest and absorb dietary fats [37]. Administration of ABE dose-dependently reduced both AUC and maximum plasma levels of postprandial triglyceride and cholesterol, showing statistically significant differences compared to the LC group (Figure 2).…”

Daily Consumption of α-Linolenic Acid Increases Conversion Efficiency to Eicosapentaenoic Acid in Mice

“…Experiment 1: α-LA or EPA was administered to mice using the oral lipid tolerance test protocol reported by Ochiai et al with some modifications [20]. Briefly, 15 male ICR mice aged 8 weeks that were consuming the control LS diet were randomly allocated to three groups: an α-LA group (3 g/kg body), an EPA group (3 g/kg), and a water group (3 mL/kg).…”