Oleic acid-induced steatosis model establishment in LMH cells and its effect on lipid metabolism

Hepatic steatosis is a highly prevalent liver disease, yet research on it is hampered by the lack of tractable cellular models in poultry. To examine the possibility of using organoids to model steatosis and detect it efficiently in leghorn male hepatocellular (LMH) cells, we first established steatosis using different concentrations of oleic acid (OA) (0.05-0.75 mmol/L) for 12 or 24 h. The subsequent detections found that the treatment of LMH cells with OA resulted in a dramatic increase in intracellular triglyceride (TG) concentrations, which was positively associated with the concentration of the inducing OA (R² > 0.9). Then, the modeled steatosis was detected by flow cytometry after NileRed staining and it was found that the intensity of NileRed-A was positively correlated with the TG concentration (R² > 0.93), which demonstrates that the flow cytometry is suitable for the detection of steatosis in LMH cells. According to the detection results of the different steatosis models, we confirmed that the optimal induction condition for the establishment of the steatosis model in LMH cells is OA (0.375 mmol/L) incubation for 12 h. Finally, the transcription and protein content of fat metabolism-related genes in steatosis model cells were detected. It was found that OA-induced steatosis could significantly decrease the expression of nuclear receptor PPAR-γ and the synthesis of fatty acids (SREBP-1C, ACC1, FASN), increasing the oxidative decomposition of triglycerides (CPT1A) and the assembly of low-density lipoproteins (MTTP, ApoB). Sterol metabolism in model cells was also significantly enhanced (HMGR, ABCA1, L-BABP). This study established, detected, and analyzed an OA-induced steatosis model in LMH cells, which provides a stable model and detection method for the study of poultry steatosis-related diseases.