Protective Effects of <i>Codium fragile</i> Extract against Acetaminophen-Induced Liver Injury

Acetaminophen (APAP) is a well-known analgesic used globally. Generally, APAP has been proven to be safe and effective at therapeutic doses; however, it can cause serious liver damage when administered at high levels. We prepared <i>Codium fragile</i> extract (CFE) using the seaweed <i>C. fragile</i> and confirmed that the CFE contains a substance called Loliolide with antioxidant activity. We performed the present study to determine whether CFE protects HEPG2 cells and BALB/c mice from oxidative stress-induced liver damage. We confirmed that CFE and Loliolide were non-cytotoxic and protected against liver damage by reducing the activities of ALT and AST, which were increased by APAP treatment, and that CFE reduced the mRNA expression of inflammatory cytokines TNF-α and IL-6 and inhibited the phosphorylation of ERK and p38 in HEPG2 cells as determined by RT-PCR and Western blot analyses. Furthermore, the TNF-α and IL-6 levels, which were increased after APAP treatment in BALB/c mice, decreased after CFE treatment. Therefore, we demonstrated that CFE exerts a protective effect against APAP-induced liver injury by suppressing the inflammatory response through anti-inflammatory activity. Our findings provide new perspectives for developing functional foods that utilize seaweeds to improve liver function.