Resveratrol inhibits cell growth by inducing cell cycle arrest in activated hepatic stellate cells Izabel C. Souza Æ Leo Anderson M. Martins Æ Barbara P. Coelho Æ Ivana Grivicich Æ Regina M. Guaragna Æ Carmem Gottfried Æ Radovan Borojevic Æ Fa ´tima Costa Rodrigues Guma Received: 1 February 2008 / Accepted: 22 April 2008 / Published online: 4 May 2008 Ó Springer Science+Business Media, LLC. 2008 Abstract Resveratrol (RSV) exerts anti-proliferative and pro-apoptotic actions in different cell lines. Hepatic stellate cells (HSCs) are major fibrogenic cell types that contribute to collagen accumulation during chronic liver disease. In the present study, the inhibitory effects of RSV on cell proliferation, cell cycle, and apoptosis were evaluated in the mouse hepatic stellate cell line GRX. Cells treated with 1 nM–1 lM of RSV demonstrated a decrease in cell growth of about 35% after 5 days. GRX cells, treated with RSV (100 nM or 1 lM), were analyzed by flow cytometry; RSV induced an increase in the number of GRX cells in the S- and sub-G1 phases. The increase in sub-G1 phase cells and the nuclear condensation and fragmentation shown by DAPI staining identified a possible pro-apoptotic effect of RSV on GRX cells. Furthermore, the RSV anti-prolifera- tive effects could be explained by an S-phase accumulation caused by a decrease in the progression through the cell cycle or an inhibition of S or G2 phase transition. It is notable that these RSV actions are mediated at nanomolar levels, compatible with the concentrations of free RSV in biological fluids after ingestion of polyphenol-rich foods, suggesting a possible effect of these foods as an adjuvant treatment in chronical liver diseases. Keywords Hepatic stellate cells Á Resveratrol Á Cell cycle Á Apoptosis Introduction Liver fibrosis is a dynamic and sophisticated regulated wound healing response to chronic hepatocellular damage that represents a major medical problem with significant morbidity and mortality. This fibrotic process results from the accumulation of extracellular matrix (ECM) proteins including collagens, proteoglycans, and glycoproteins [1]. Hepatic stellate cells (HSCs) (previously known as Ito cells, lipocytes, or fat storing cells) are liver-specific peri- cytes which were identified as a major source of collagen in pathologic fibrosis following their activation to miofibro- blast-like cells [2]. Indeed, much of the knowledge on the cell and molec- ular biology of liver fibrosis has been gained through animal models and from in vitro models employing culture activated HSC isolated from rat, mouse, or human liver. From these, in vitro models grew a large body of infor- mation characterizing stellate cell activation, cytokine signaling, intracellular pathways regulating liver fibrogen- esis, production of extracellular matrix proteins, and development of antifibrotic drugs [3]. In this study, we used the GRX cell line, established from hepatic fibrogranulomatous reactions, which mobi- lizes adjacent stellate cells. Under standard conditions, these cells express a transitional myofibroblast phenotype and present morphological and biochemical aspects of hepatic connective tissue [4–6]. It has been previously demonstrated that the GRX cell line can be induced, in vitro, to express alternative phenotypes. The lipocyte I. C. Souza Á L. A. M. Martins Á B. P. Coelho Á R. M. Guaragna Á C. Gottfried Á F. C. R. Guma (&) Departamento de Bioquı ´mica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-anexo, CEP 90035- 003 Porto Alegre, RS, Brazil e-mail: fatima.guma@ufrgs.br I. C. Souza Á I. Grivicich ULBRA, Canoas, RS, Brazil R. Borojevic Departamento de Histologia e Embriologia, ICB, PABCAM, UFRJ, Rio de Janeiro, RJ, Brazil 123 Mol Cell Biochem (2008) 315:1–7 DOI 10.1007/s11010-008-9781-x