Effect of a glycoprotein from Hizikia fusiformis on acetaminophen-induced liver injury

In this study, we isolated a glycoprotein from the brown alga Hizikia fusiformis (HFGP) and examined whether it could protect against Acetaminophen (AAP)-induced liver injury in vivo and in vitro. AAP, one of the most commonly abused drugs, may cause fatal liver injury. An analysis of the effects of HFGP on AAP toxicity in rats revealed that the serum glutamic pyruvic transaminase level was restored to the control level and glutathione level was also increased by co-treatment with HFGP and AAP. Furthermore, HFGP co-treatment decreased caspase-3/-9 activity. These results indicate that HFGP may inhibit AAP-induced liver injury in Sprague-Dawley rats. Several lines of evidence indicate that oxidative stress plays an important role in AAP-induced liver injury and mitogen-activated protein kinase (MAPK) signaling is involved in the regulation of oxidative stress. Therefore, Western blotting was used to determine which MAPK signaling pathway is involved in the protective effect of HFGP against AAP toxicity in HepG2 cells. We found that ERK activation was involved in the protective effect of HFGP against AAP-induced cell death. Therefore, we propose that MAPK signaling is involved in the protective effect of HFGP against AAP-induced liver injury.