Intracellular alpha-fetoprotein mitigates hepatocyte apoptosis and necroptosis by inhibiting endoplasmic reticulum stress

Figure 3 Endoplasmic reticulum stress up-regulates alpha-fetoprotein expression in hepatocytes. Male BALB/c mice were untreated (NC), or treated with phosphate buffer saline (control) or TM for 24 h or 48 h. LO2 cells were untreated (NC), or treated with dimethyl sulfoxide (control) or thapsigargin (TG) for 24 h, and 48 h. A: Serum alanine aminotransferase levels; B: Serum total bilirubin levels; C: Western blot analysis of the relative levels of proteins; D: Immunohistochemical analysis of alpha-fetoprotein (AFP) expression and hematoxylin and eosin staining analysis of liver injury in mice at 24 h post endoplasmic reticulum stress. The positive expression of AFP was stained with brownish yellow and indicated by a plus sign. Hash sign indicates the area of necrosis; E: Chemiluminescence immunoassay of serum AFP levels in mice; F: The levels of AFP in the supernatants of cultured cells; G: Cell counting kit-8 analysis of the cell viability; H: Western blot analysis of the relative levels of p-protein kinase R-like endoplasmic reticulum kinase, ATF6 and AFP expression in LO2 cells. AFP: Alpha-fetoprotein; ALT: Alanine aminotransferase; ATF6: Activating transcription factor-6; CCl₄: Carbon tetrachloride; CCK-8: Cell counting kit-8; DMSO: Dimethyl sulfoxide; H&E: Hematoxylin and eosin; IHC-P: Immunohistochemistry-paraffin; PBS: Phosphate buffer saline; p-PERK: Phosphorylated protein kinase R-like endoplasmic reticulum kinase; TBil: Total Bilirubin; TM: Tunicamycin; TG: Thapsigargin. ^bP < 0.01, compared with the control group; ^dP < 0.01, compared with the 0 h group in HepG2 cells.