Protein Phosphatase 4 Promotes Hepatocyte Lipoapoptosis by Regulating RAC1/MLK3/JNK Pathway

Figure 3

PP4 regulated lipoapoptosis in the liver of western diet-fed mice. Six- to eight-week-old male C57BL/6J mice fed with western diet for 16 weeks were injected with control AD, AD-PP4shRNA, or AD-PP4 ( for each group) through the tail vein and sacrificed 10 days postinjection. Body weight and liver weight in western diet-fed mice (a, e, f) and western diet-fed mice injected with control AD, AD-PP4shRNA, or AD-PP4 (h–j). Oil red O staining, TUNEL staining, and/or H&E staining of frozen liver sections in western diet-fed mice (scale bar: 50 μM) (b) and western diet-fed mice injected with control AD, AD-PP4shRNA, or AD-PP4 (l) (scale bar: 20 μM). Serum ALT and AST levels were measured in western diet-fed mice (g) and western diet-fed mice injected with control AD, AD-PP4shRNA, or AD-PP4 (k). Western blots of hepatic PP4, PUMA, Bim, c-caspase 3, and phosphorylation levels of JNK in western diet-fed mice (c), western diet-fed mice injected with AD-PP4shRNA (m), and AD-PP4 (o). Relative protein levels were quantified by densitometry and normalized by GAPDH (d, n, p). Data are expressed as , and statistical significance for protein levels was determined by one-way ANOVA (Tukey-Kramer honestly significant difference), (, ).

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