%0 Journal Article
%T Effects of Three Different Fibrates on Intrahepatic Cholestasis Experimentally Induced in Rats
%A Alaa El-Sisi
%A Sahar Hegazy
%A Eman El-Khateeb
%J PPAR Research
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/781348
%X Background. Activation of PPAR¦Á modulates cholesterol metabolism and suppresses bile acid synthesis. This study aims to evaluate the effect of PPAR¦Á agonists, fenofibrate, bezafibrate, and gemfibrozil, on acute cholestasis induced by ethinylestradiol (EE) plus chlorpromazine (CPZ) in rats. Method. 100 male albino rats (150¨C200£¿gm) were divided randomly into 10 equal groups. Control group received 1% methylcellulose vehicle; disease group received CPZ plus EE for 5 consecutive days; four groups received either ursodeoxycholic acid, fenofibrate, bezafibrate, or gemfibrozil for 7 days; 2 days before EE + CPZ, three other groups received one of the three fibrates after GW6471, a selective PPAR¦Á antagonist in addition to EE + CPZ. The final group received GW6471 alone. Results. The three fibrates showed marked reduction ( ) in serum levels of ALP, GGT, ALT, AST, total bile acids, bilirubin, TNF¦Á, and IL-1¦Â and in hepatic malondialdehyde level as well as a significant increase in bile flow rate ( ) in addition to improvements in histopathological parameters compared to diseased group. In groups which received GW6471, these effects were completely abolished with fenofibrate and partially blocked with bezafibrate and gemfibrozil. Conclusion. Short-term administration of fibrates to EE/CPZ-induced intrahepatic cholestatic rats exerted beneficial effects on hepatocellular damage and apoptosis. Fenofibrate anticholestatic effect was solely PPAR¦Á dependent while other mechanisms played part in bezafibrate and gemfibrozil actions. 1. Background Cholestasis is defined as a disturbance of bile secretion that can result from a functional defect in bile formation at the level of hepatocytes or from impaired bile secretion and flow at the bile duct level [1]. It results in intrahepatic accumulation of cytotoxic bile acids, which cause liver damage ultimately leading to biliary fibrosis and cirrhosis and ultimately end-stage liver disease requiring liver transplantation. Cholestatic liver injury is counteracted by a variety of adaptive hepatoprotective mechanisms including alterations in bile acid transport, synthesis, and detoxification [2]. Because the intrinsic adaptive response to bile acids cannot fully prevent liver injury in cholestasis, therapeutic targeting of many nuclear receptors via specific and potent agonists may further enhance the hepatic defense against toxic bile acids. Therefore nuclear receptors (NRs) are promising therapeutic targets for cholestatic liver diseases [3]. Peroxisome proliferator-activated receptor alpha (PPAR¦Á), farnesoid X receptor
%U http://www.hindawi.com/journals/ppar/2013/781348/