PARP inhibition prevents acetaminophen-induced liver injury and increases survival rate in rats.

Background/aim: Acetaminophen (APAP) overdose results in severe liver damage that may develop into acute liver failure. Recent studies have demonstrated that inhibition of poly(ADP-ribose) polymerase (PARP) decreases tissue necrosis and inflammation. We evaluated the efficacy of 3-aminobenzamide (3-AB), a PARP inhibitor, in a rodent model of APAP-induced hepatotoxicity.

Materials And Methods: Twenty-four Sprague-Dawley rats were divided equally into 3 experimental groups: sham group, APAP group, and APAP + 3-AB group. In the experimental treatment groups APAP was administered orally at 1 g/kg and, in the APAP + 3-AB group, 3-AB was administered intraperitoneally at a dose of 20 mg/kg exactly 1 h after APAP treatment. Surviving animals were euthanized 48 h after initial APAP administration. Blood samples and liver tissues were collected for histopathological and biochemical analysis.

Results: A panel of oxidative stress parameters, as well as serum aspartate aminotransferase, alanine aminotransferase, neopterin, and nitrite/nitrate and histological injury scores, were significantly reduced among the APAP + 3-AB treatment group relative to the group treated with APAP alone (P < 0.05, APAP vs. APAP + 3-AB).

Conclusion: The present study demonstrates that 3-AB inhibited APAP-induced hepatic injury and reduced neopterin levels. Results of the present study indicate that PARP inhibitors may be an effective adjuvant therapy resulting in improved outcomes in APAP-induced hepatotoxicity.