Mol. Nutr. Food Res. 2013, 00, 1–5 1 DOI 10.1002/mnfr.201200693 FOOD &FUNCTION Effects of raftilose on serum biochemistry and liver morphology in rats fed with normal or high-fat diet In ˆ es Correia-S ´ a 1 , Hugo de-Sousa-Lopes 1 , Maria J. Martins 2 , Isabel Azevedo 2 , Eduardo Moura 3 and Maria A. Vieira-Coelho 1,3 1 Institute of Pharmacology & Therapeutics,, Faculty of Medicine, University of Porto, Porto, Portugal 2 Department of Biochemistry,, Faculty of Medicine, University of Porto, Porto, Portugal 3 Institute for Molecular and Cell Biology, University of Porto, Porto, Portugal Non-alcoholic fatty liver disease is the leading cause of chronic liver injury in developed coun- tries. Oligofructose (OFS) is a prebiotic with proven benefits for health. The aim of the study is to evaluate the effect of 10% OFS on hepatic morphology and lipid metabolism in Wistar Kyoto rats submitted to normal diet (ND) or high-fat diet (FD). Animals were treated for 7 weeks. Lipid profile and serum alkaline phosphatase (ALP) activity were measured and liver histology evaluated at the end of the study. Ten percent OFS reduced triglyceride (TAG) levels when added to any of the diet regimens; 10% OFS decreased plasmatic urea in ND and plasmatic and urinary urea levels in FD; ND + 10% OFS treated rats showed lower ALP activity than con- trols. FD increased ALP activity, an effect not reversed by OFS. Animals submitted to FD have microscopic hepatic changes: marked steatosis with disarranged centrilobular zone structure; enlarged sinusoids; enlarged mitochondria and an increase in number and volume of adipo- somes. Supplementation with 10% OFS in FD reversed those effects. In conclusion, 10% OFS supplementation prevented deleterious effects of FD such as alterations on lipid profile (TAG elevation) and hepatic morphologic changes. OFS decreased ALP activity in animals subjected to ND, which may have contributed to the differences on lipid metabolism. Keywords: Alkaline phosphatase / Hepatic / NAFLD / Oligofructose / Raftilose P95 R  Received: October 17, 2012 Revised: January 3, 2013 Accepted: February 27, 2013  Additional supporting information may be found in the online version of this article at the publisher’s web-site Non-alcoholic fatty liver disease (NAFLD), first described in 1980 by Ludwig et al. [1], is defined by elevated liver enzyme in individuals who are not heavy drinkers and have negative serological tests for viral hepatitis, autoimmune liver disease and congenital causes of chronic hepatitis. Despite initially showing no deleterious effects, it can progress to steatohep- atitis, cirrhosis and hepatocellular carcinoma and has been associated with higher rates of liver-related, cardiovascular Correspondence: Professor Maria Augusta Vieira-Coelho, Insti- tute of Pharmacology and Therapeutics, Faculty of Medicine, Uni- versity of Porto, Alameda Prof. Hern ˆ ani Monteiro, 4200–319 Porto, Portugal E-mail: mavc@med.up.pt Fax: +351-225502402 Abbreviations: ALP, alkaline phosphatase; FD, high fat diet; In- tALP, intestinal isoenzyme; NAFLD, non-alcoholic fatty liver dis- ease; ND, normal diet; OFS, oligofructose; TAG, triglyceride and malignancy deaths [2]. Although its etiology is not com- pletely understood, NAFLD is associated with insulin resis- tance, type 2 diabetes, obesity and hypertriglyceridemia and it has been suggested that it might be the liver component of metabolic syndrome [3]. Estimates suggest that 20–30% of individuals in developed countries have NAFLD, with higher prevalence in obese and diabetic population [3]. This highlights the urgent need for efficient prevention and treatment for NAFLD. Prebiotics are non-digestible or low digestible food ingredients that benefit the host organism by selectively stimulating the growth or activity of health-promoting probiotic bacteria in the colon (Bifidobacteria and some Gram-negative bacteria) [4]. Oligofructose (OFS) is a car- bohydrate with (1–2)-fructose chain structure, that is not hydrolysed by human digestive enzymes but fermented by probiotic bacteria, producing lactate and SCFA such as ac- etate, propionate and butyrate [5]. A diet supplemented with OFS can lower plasma triglyceride (TAG) and cholesterol C  2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.mnf-journal.com