Sulfhydrylated albumin mitigates Acetaminophen-induced liver injury by restoring the integrated HS-albumin thiol antioxidant network.

Acetaminophen (APAP) overdose is the leading cause of acute liver failure and a major global health issue. APAP hepatotoxicity is primarily driven by oxidative stress resulting from the depletion of hepatic glutathione (GSH). Given that hydrogen sulfide (HS) and albumin are crucial components of the thiol antioxidant system, we hypothesized they play a critical role in the body's defense against APAP-induced liver injury (AILI). This study aimed to test this hypothesis and explore novel therapeutic approach. Administration of APAP to mice induced significant hepatic damage, associated with marked local and systemic oxidative stress, evidenced by elevated serum transaminases and oxidative injury markers. Furthermore, APAP exposure disrupted the hepatic HS-generating system, leading to reduced expression of HS-synthesizing enzymes and decreased levels of HS and protein persulfidation (-SSH) in both liver and serum. Pharmacological inhibition of endogenous HS production dramatically exacerbated APAP hepatotoxicity and mortality. Conversely, supplementation with a modified persulfide-rich albumin (Alb-SSH) significantly alleviated hepatocyte injury. These findings were similarly observed in cultured hepatocytes. Mechanistic analysis revealed that Alb-SSH increased HS levels by releasing HS and restoring HS-synthesizing enzymes. It improved both hepatic and systemic oxidative status and rebalanced the intra- and extracellular GSH/GSSG ratio. At the molecular level, Alb-SSH directly scavenged reactive oxygen species and integrated with the GSH/GSSG system via thiol-disulfide exchange reactions. Collectively, our study establishes HS and Alb-SSH as integral components of a coordinated thiol antioxidant network that counteracts AILI. Supplementation with Alb-SSH represents a promising therapeutic strategy for AILI and other oxidative stress-associated diseases.