Urotensin Ⅱ在急性肝衰竭小鼠肝组织中的表达及损伤作用

Effect of urotensin II/urotensin II receptor system on autophagy in acute liver failure in mice

AIM

To investigate the effect of urotensin II/urotensin II receptor (UII/UT) system on the levels of hepatic autophagy in mice with acute liver failure (ALF).

METHODS

Male Balb/c mice were randomly divided into four groups (n = 6 each): normal controls (group A), pre-treated controls (group B), model mice (group C), and pre-treated model mice (group D). Groups B and D received urantide (0.6 mg/kg body weight) via caudal vein injection. At 30 min post-injection, groups C and D were intraperitoneally injected with LPS/D-GalN to induce acute liver injury. Serum and liver tissue samples were collected 6 h later. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels were determined to assess liver injury. The expression of autophagy related genes such as Beclin-1, autophagy related 5 (Atg5), Atg7, sequestosome 1 (Sqstm1/p62), and microtubule-associated protein 1 light chain 3 (LC3) was detected by quantitative PCR. The expression of autophagic proteins LC3 and p62 was tested by Western blot.

RESULTS

Serum ALT and AST levels in group C were significantly higher than those in groups A and B (P < 0.01), while they were significantly lower in group D than in group C (P < 0.01). RT-PCR analysis showed that the expression of autophagy related genes such as Beclin-1, Atg5, Atg7, p62, LC3 was downregulated in groups C and D compared to groups A and B (P < 0.05), although there was no difference between groups C and D as well as between groups A and B (P > 0.05). LC3II and p62 protein levels tested by Western blot were significantly lower in groups C and D than in groups A and B (P < 0.05), but there was no difference between groups C and D as well as between groups A and B (P > 0.05).

CONCLUSION

UII/UT system has no influence on the suppressed hepatic autophagy in ALF mice.