ORIGINAL PAPER Effect of dietary fiber of “Rihane” barley grains and azoxymethane on serum and liver lipid variables in Wistar rats Lamia Lahouar & Fatma Ghrairi & Mouldi El Felah & Hichem Ben Salem & Abdel Hedi Miled & Mohamed Hammami & Lotfi Achour Received: 3 April 2010 / Accepted: 6 September 2010 / Published online: 18 September 2010 # University of Navarra 2010 Abstract The aim of the present study is to evaluate the effects of diet enriched with dietary fiber of barley variety “Rihane” and azoxymethane on serum and liver lipid variables in male rats. Forty male rats were divided into four groups and fed on control diet or experimental diet that contained control enriched with dietary fiber of barley variety “Rihane”. Animals were injected with saline (controls) or azoxymethane (20 mg/kg body weight s.c.) at 7 and 8 weeks of age. The experimental diet significantly decreased cholesterol level compared with the control diet. Rats fed with BR diet significantly increased the serum high-density lipoprotein (HDL) cholesterol and sig- nificantly decreased low-density lipoprotein (LDL) cholesterol concentrations. The experimental diet decreased the atherogenic index (p <0.05) compared with the control diet. Whereas the azoxymethane induced a significant increase of liver lipid, serum LDL and triglyceride concentrations, but it caused a significant reduction of HDL. Consequently, the ratio of HDL/TC decreased significantly compared with the control (p <0.05). Accordingly, these results indicated that the diet enriched with dietary fiber of barley variety “Rihane” could be effective in decreas- ing the atherogenic risk factors in rats whereas the use of the azoxymethane as colon-specific carcinogen substance altered the lipid metabolism. Keywords Barley variety “Rihane” . Liver . Serum . Cholesterol . Azoxymethane Abbreviations ADF Acid detergent fiber ADL Acid detergent lignin AOM Azoxymethane BR Barley “Rihane” BW Body weight CVD Cardiovascular disease J Physiol Biochem (2011) 67:27–34 DOI 10.1007/s13105-010-0045-3 L. Lahouar (*) : F. Ghrairi : L. Achour Unité de recherche 03/UR/09-01 “Génome, Diagnostic Immunitaire et valorisation”, Institut Supérieur de Biotechnologie de Monastir, Rue Tahar Hadded, BP 74, Monastir 5019, Tunisia e-mail: lahouarlamia@yahoo.fr M. El Felah Laboratoire des Grandes Cultures, INRA-Tunisia, 2049 Ariana, Tunisia H. B. Salem Laboratoire des Productions Animales et Fourragères, INRAT, 2049 Ariana, Tunisia A. H. Miled Laboratoire de Biochimie, Hôpital Farhat Hachad Sousse, Sousse, Tunisia M. Hammami Laboratoire de Biochimie, UR 08/39 “Nutrition Humaine et Désordres Métaboliques”, Faculté de Médecine de Monastir, Monastir, Tunisia