Spontaneously Diabetic Torii (SDT) fatty rats, a new obese diabetic model, reportedly presented with features of non-
alcoholic steatohepatitis (NASH) after 32 weeks of age. We tried to accelerate the onset of NASH in SDT fatty rats using
dietary cholesterol loading and noticed changes in the blood
choline level which is expected to be a NASH
biomarker.
Body weight and biochemical parameters were measured from 8 to 24 weeks of age. At 16, 20, 24 weeks, pathophysiological analysis of the livers were performed. Hepatic
lipids,
lipid peroxides, and the expression of
mRNA related to
triglyceride (TG) synthesis,
inflammation, and
fibrosis were evaluated at 24 weeks. Hepatic
fibrosis was observed in SDT fatty rats fed
cholesterol-enriched diets (SDT fatty-Cho) from 16 weeks. Furthermore, hepatic
lipids and
lipid peroxide were significantly higher in SDT fatty-Cho than SDT fatty rats fed normal diets at 24 weeks. Hepatic
mRNA expression related to TG secretion decreased in SDT fatty-Cho, and the
mRNA expression related to
inflammation and
fibrosis increased in SDT fatty-Cho at 24 weeks. Furthermore, SDT fatty-Cho presented with increased plasma
choline, similar to human NASH. There were no significant changes in the effects of feeding a
cholesterol-enriched diet in Sprague-Dawley rats. SDT fatty-Cho has the potential to become a valuable animal model for NASH associated with
type 2 diabetes and
obesity.