Effect of Western diet on body composition, locomotor performance and blood biochemical profile in the bank vole

Abstract

ObjectiveThe adverse effects of diets high in both fat and simple sugars ("Western diets", WD), which are one of the causes of the epidemics of obesity and related disorders, have been extensively studied in laboratory rodents, but not in non-laboratory animals, which limits the scope of conclusions. For example, a few studies have shown that, unlike the laboratory mice or rats, non-laboratory rodents that reduce body mass for winter do not develop obesity when fed a high-fat diet. However, it is not known whether these rodents are also resistant to the adverse effects of WD. Here, we investigated the effects of WD on body composition, locomotor performance and blood biochemical profile in such a rodent, the bank vole (Clethrionomys = Myodes glareolus). MethodsYoung voles were fed either a standard diet or one of six versions of WD (varying in fat, sucrose, and cholesterol content) from the age of 21 days until adulthood (16 individuals per group), and then several morpho-physiological and biochemical traits were analyzed. ResultsNeither body mass, fat content nor blood glucose were elevated by WD (p[≥]0.11). Basal metabolic rate, sprint speed, endurance distance, and aerobic exercise capacity were also not significantly affected by the diet (p[≥]0.2). However, altered respiratory exchange rates indicated altered metabolic pathways, and the liver and spleen were enlarged in the groups fed WD with added cholesterol (p[≤]0.002). Similarly, concentrations of cholesterol, high-density lipoprotein (HDL), non-HDL, glutamic pyruvic transaminase, glutamic oxaloacetate transaminase (GOT), and lactate dehydrogenase (LDH) were elevated in the WD groups, especially the cholesterol-supplemented WD (p[≤]0.0001), indicating altered liver function. ConclusionsBank voles appeared to be resistant to diet-induced obesity and diabetes, but not to other adverse effects of WD, especially cholesterol-supplemented WD. Therefore, the bank vole is a promising model species to study diet-induced liver disease in lean individuals.