An in vitro model applicable for fatty liver lipotoxicity pharmacological research / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To establish an in vitro model applicable for fatty liver lipotoxicity pharmacological research.</p><p><b>METHODS</b>HepG2 cells were cultured with rat serum instead of fetal bovine serum and with long-chain free fatty acid (FFA) added. The tested indices were: the content of serum TNFa, cellular triglycerides (TG) content, Oil Red staining and ultrastructural changes; protein expression and gene expression of cellular TNFa, and the expression and distribution of cathepsin B (Ctsb).</p><p><b>RESULTS</b>After incubation with FFA for 24 hours, the TG deposition of HepG2 in the model group increased markedly and TG content was 627.24 mg/g protein (t = 23.6, P less than 0.01), TNFa content in the cell supernatant also increased to 52.04 pg/mg protein (t = 2.6, P less than 0.05). Compared with those of the normal group, the protein expression and mRNA expression of cellular TNFa and Ctsb also increased significantly.</p><p><b>CONCLUSION</b>FFA could induce a model of HepG2 steatosis with TNFa secretion through the Ctsb signal pathway using rat serum in the culture media. The method is simple and economical, which is an ideal model applicable for fatty liver lipotoxicity pharmacological research.</p>

Study on effects of extracts from Salvia Miltiorrhiza and Curcuma Longa in inhibiting phosphorylated extracellular signal regulated kinase expression in rat's hepatic stellate cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To study the effect of salvianolic acid B (SAB) and curcumin, the extracts of Salvia Miltiorrhiza and Curcuma Longa, on the proliferation and activation of hepatic stellate cell (HSC), and the extracellular signal regulated kinase (ERK) expression in it.</p><p><b>METHODS</b>Rat's HSC-T6 were cultured and treated by SAB or curcumin. The inhibitory effect on cell proliferation was determined by 3-(4, 5-dimthyl-2-2thiazoly)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) colorimetry, and the expression levels of alpha smooth actin (alpha-SMA), collagen type I, and ERK were determined by Western blot.</p><p><b>RESULTS</b>SAB and curcumin inhibited the proliferation and activation of rat's HSC-T6 in dose-dependent fashion and significantly reduced the expression level of alpha-SMA (P < 0.01). Curcumin significantly reduced the expression of collagen type I (P < 0.05). Both SAB and curcumin showed insignificant effect on the ERK expression level, but they could significantly reduce the level of phosphorylated-ERK expression, showing significant difference as compared with that in the control group (P < 0.01 and P < 0.05 respectively).</p><p><b>CONCLUSION</b>SAB and curcumin could significantly inhibit the proliferation, activation of HSC, and the production of type I collagen in HSC, the mechanism may be associated with their inhibition on ERK phosphorylation.</p>