Selective Action of Human Sera Differing in Fatty Acids and Cholesterol Content on In Vitro Gene Expression Hylde Zirpoli, 1 Mariella Caputo, 1 Antonio Carraturo, 2 Gaetano Torino, 1 Alessia Fazio, 3 Mohamed Attya, 3 Luca Rastrelli, 1 and Mario Felice Tecce 1 * 1 Department of Pharmaceutical and Biomedical Sciences, University of Salerno, via Ponte Don Melillo, 84084 Fisciano, Salerno, Italy 2 Clinical Pathology Laboratory, S. Maria Goretti Hospital, AUSL, Via Canova 3, 04100, Latina, Italy 3 Department of Chemistry, University of Calabria, via Pietro Bucci, 87036 Arcavacata di Rende, Cosenza, Italy ABSTRACT Serum constituents might directly affect metabolic diseases pathogenesis and are commonly used as diagnostic tool. The aim of this study was to investigate the human serum effect on in vitro gene expression, related to nutrients action and involved in lipid metabolism. In detail, 40 human sera were firstly analyzed in fatty acids profile by gas-chromatography. Then samples were tested through direct addition within culture medium on Hep G2 human hepatoma cells, comparing samples from hypercholesterolemic (average 273 mg/dl) versus normocho- lesterolemic male subjects (average 155 mg/dl), since this condition is a relevant disease risk factor and is typically consequent to nutritional style. Hypercholesterolemic sera produced a 0.4-fold reduction of sterol regulatory element binding protein 1c (SREBP-1c) mRNA ( P < 0.05) and a 1.5-fold increase of UDP-glucuronosyltransferase 1A1 (UGT1A1) mRNA ( P < 0.01). Samples with higher concentrations of n-6 fatty acids produced a higher expression of UGT1A1 mRNA. Total fatty acids [docosahexaenoic, eicosopentanoic, arachidonic, linolenic, and linoleic acid (DHA, EPA, AA, LNA, and LA, respectively)] in each serum resulted roughly inverse with trend of SREBP-1c mRNA expression. Serum AA, LA, and trans fatty acids were more abundant in hypercholesterolemic subjects ( P < 0.01) while DHA as quota of detected fatty acids was significantly higher in normocholesterolemic subjects ( P < 0.05). While it is not possible to indicate which component was responsible for the observed gene modulations, our data indicate that sera differing in lipid profiles, mainly associated with dietary behavior, differentially affect gene expression known to be involved in metabolic and nutritional related conditions. J. Cell. Biochem. 113: 815–823, 2012. ß 2011 Wiley Periodicals, Inc. KEY WORDS: CHOLESTEROL; GENE EXPRESSION; POLYUNSATURATED FATTY ACIDS; SERUM LIPIDS; DOCOSAHEXANEOIC ACID; EICOSOPENTANOIC ACID B oth in physiological and pathological conditions, human serum composition results from a combined action of endogenous metabolism and nutritional intake. Lipid component quality and quantity of human serum are relevant reference markers of cardiovascular disease risk and mortality [Warensjo ¨ et al., 2008]. Dietary fat intake strictly affects serum lipid profile and cardio- vascular disease epidemiology. In particular, fatty acids derived from diet have different effects on disease risk: higher intakes of long chain n-3 fatty acids from fish oil has been consistently reported as lowering disease incidence while trans fatty acids had negative influence [Erkkila ¨ et al., 2008]. Molecular mechanisms accounting for these effects are numerous and partially known; n-3 fatty acids have distinct capacities, selectively influencing both cellular metabolic functions and gene transcription and expression [Deckelbaum et al., 2006]. Serum composition and more particularly its lipids, including fatty acids, might then exert a direct role specifically affecting tissue gene expression both within physiolog- ical and pathological states. Journal of Cellular Biochemistry ARTICLE Journal of Cellular Biochemistry 113:815–823 (2012) 815 Abbreviations used: DHA, docosahexaenoic acid; EPA, eicosopentanoic acid; AA, arachidonic acid; LNA, linolenic acid; LA, linoleic acid; FAME, fatty acid methyl esters; FBS, fetal bovine serum; FID, flame ionization detection; LXR, liver X receptor; RXR, retinol X receptor; SREBP-1c, sterol regulatory element binding protein 1c; SCD, stearoyl-CoA desaturase; UGT1A1, UDP-glucuronosyltransferase 1A1; UCP2, uncoupling protein 2. The authors declared no conflict of interest. Grant sponsor: University of Salerno; Grant number: FARB 2009 and 2010. *Correspondence to: Prof. Mario Felice Tecce, Department of Pharmaceutical and Biomedical Sciences, University of Salerno, via Ponte Don Melillo, 84084 Fisciano, Salerno, Italy. E-mail: tecce@unisa.it Received 8 September 2011; Accepted 6 October 2011  DOI 10.1002/jcb.23409  ß 2011 Wiley Periodicals, Inc. Published online 20 October 2011 in Wiley Online Library (wileyonlinelibrary.com).