An Experimental Model of Hepatic Steatosis to Detect Lipid Accumulation

Abstract

Obesity is associated with an increased risk of metabolic syndromes such as type 2 diabetes, insulin resistance, dyslipidaemia and non-alcoholic fatty liver disease. Obesity occurs as a result of an imbalance between food intake and energy expenditure leading to excessive accumulation of adipose tissue. NAFLD is the most common liver condition and related to the resistance of insulin. Insulin resistance is associated with an increased influx of lipid into the liver promoting accumulation of hepatic triglyceride. This study aims to develop an experimental model of hepatic steatosis with lipid over-accumulation. HepG2 cells were cultured for 24 hours in free fatty acid media (1:2 palmitic acid and oleic acid respectively). Intracellular lipid content and lipotoxicity were determined by oil red O staining followed by colorimetric detection. This experiment was accomplished by defining the experimental conditions of lipid exposure that leads to significant intracellular fat accumulation in the absence of lipotoxicity with 1 mM of free fatty acid media. As a result, oleic and palmitic acids could be over-accumulated in HepG2 cells. 1 mM free fatty acid media did not affect the cell integrity and did not cause lipotoxicity of the cells.