Histological evaluation of liver sections from Control-, NASH-, HFD- and HFr-fed rats. Row 1: representative H&E-stains of normal liver from a Control-fed rat, and hepatic steatosis in b NASH-fed rat, c HFD-fed rat and d HFr-fed rat. Hepatic steatosis in HFD-fed rats was almost exclusively found to be microvesicular (c); in HFr-fed rats almost exclusively macrovesicular (d); while steatosis in NASH-fed rats represented an intermediate between the two, with both macro- and microvesicular steatosis (b). Row 2: higher magnification of representative H&E stained liver sections. e Liver morphology appeared normal in Control-fed rats, whereas inflammatory infiltrates were observed in livers from f NASH-fed rats, g HFD-fed rats and h HFr-fed rats Row 3: Oil Red O stains of liver sections from j NASH-fed rats, k HFD-fed rats and l HFr-fed rats confirmed hepatic steatosis observed in b–d. i Oil Red O staining of liver from Control-fed rat