Pablo J Giraudi1, Varenka J Barbero Becerra2, Veronica Marin1, Norberto C Chavez-Tapia2, Claudio Tiribelli3, Natalia Rosso4. 1. Fondazione Italiana Fegato, Centro Studi Fegato, Area Science Park Basovizza Bldg. Q SS14 Km 163.5, 34149 Trieste, Italy. 2. Fondazione Italiana Fegato, Centro Studi Fegato, Area Science Park Basovizza Bldg. Q SS14 Km 163.5, 34149 Trieste, Italy; Liver Research Unit, Médica Sur Clinic & Foundation, Puente de Piedra 150, Col. Toriello Guerra, Tlalpan, C.P. 14050 Mexico City, Mexico. 3. Fondazione Italiana Fegato, Centro Studi Fegato, Area Science Park Basovizza Bldg. Q SS14 Km 163.5, 34149 Trieste, Italy; Department of Medical Sciences, University of Trieste, 34100 Trieste, Italy. 4. Fondazione Italiana Fegato, Centro Studi Fegato, Area Science Park Basovizza Bldg. Q SS14 Km 163.5, 34149 Trieste, Italy. Electronic address: natalia.rosso@csf.units.it.
Abstract
BACKGROUND & AIMS: Non-alcoholic fatty liver disease is characterized by an initial accumulation of triglycerides that can progress to non-alcoholic steatohepatitis, which can ultimately evolve to cirrhosis and hepatocellular carcinoma. Hepatic stellate cells play a key role in liver fibrogenesis by an increased activation and an altered profile of genes involved in the turnover of extracellular matrix components. To reproduce in-vitro the functional cell connections observed in vivo it is essential to consider cell-to-cell proximity and interaction. The aim of this study was to determine the response to free fatty acids in a simultaneous co-culture model of hepatocytes and hepatic stellate cells. METHODS: Simultaneous co-culture model and monoculture of each cell type (control) were exposed to FFA for 24 up to 144 h. Quantification of steatosis; stellate cell activation; assessment of fibrogenic response; expression and activity of metalloproteinases as well as collagen biosynthesis were evaluated. RESULTS: Free fatty acids induced comparable steatosis in simultaneous co-culture and monoculture. However, the activation of the stellate cells assessed by alpha-smooth muscle actin expression is greater when cells were in close contact. Furthermore, a time-dependent increment of tissue inhibitor metalloproteinase-2 protein was observed, which was inversely correlated with protein expression and activity of matrix-metalloproteinases, suggesting enhanced collagen biosynthesis. This behavior was absent in cell monoculture. CONCLUSIONS: These data indicate that cell-to-cell proximity between hepatocytes and stellate cells is necessary for the initiation of the fibrotic process.
BACKGROUND & AIMS:Non-alcoholic fatty liver disease is characterized by an initial accumulation of triglycerides that can progress to non-alcoholic steatohepatitis, which can ultimately evolve to cirrhosis and hepatocellular carcinoma. Hepatic stellate cells play a key role in liver fibrogenesis by an increased activation and an altered profile of genes involved in the turnover of extracellular matrix components. To reproduce in-vitro the functional cell connections observed in vivo it is essential to consider cell-to-cell proximity and interaction. The aim of this study was to determine the response to free fatty acids in a simultaneous co-culture model of hepatocytes and hepatic stellate cells. METHODS: Simultaneous co-culture model and monoculture of each cell type (control) were exposed to FFA for 24 up to 144 h. Quantification of steatosis; stellate cell activation; assessment of fibrogenic response; expression and activity of metalloproteinases as well as collagen biosynthesis were evaluated. RESULTS:Free fatty acids induced comparable steatosis in simultaneous co-culture and monoculture. However, the activation of the stellate cells assessed by alpha-smooth muscle actin expression is greater when cells were in close contact. Furthermore, a time-dependent increment of tissue inhibitor metalloproteinase-2 protein was observed, which was inversely correlated with protein expression and activity of matrix-metalloproteinases, suggesting enhanced collagen biosynthesis. This behavior was absent in cell monoculture. CONCLUSIONS: These data indicate that cell-to-cell proximity between hepatocytes and stellate cells is necessary for the initiation of the fibrotic process.
Authors: Melissa A Linden; Ryan D Sheldon; Grace M Meers; Laura C Ortinau; E Matthew Morris; Frank W Booth; Jill A Kanaley; Victoria J Vieira-Potter; James R Sowers; Jamal A Ibdah; John P Thyfault; M Harold Laughlin; R Scott Rector Journal: J Physiol Date: 2016-05-27 Impact factor: 5.182
Authors: Mary P Moore; Rory P Cunningham; Rachel A H Davis; Sarah E Deemer; Brandon M Roberts; Eric P Plaisance; R Scott Rector Journal: Am J Physiol Gastrointest Liver Physiol Date: 2021-01-27 Impact factor: 4.052