The current study aims to investigate the possible protective effect of escin, the active constituent of a natural mixture of triterpene saponin glycoside, against immune-mediated hepatitis driven by concanavalin A (Con A) and to elucidate its possible underlying mechanisms. Adult male mice were administered Con A (15 mg/kg, intravenously) for 8 h. In the treated groups, mice were pretreated with escin daily (10 mg/kg in CMC, orally) for 4 days before Con A intoxication. In addition, escin was administered in a group to examine its effect on normal mice. Our results showed that escin inhibited Con A-induced elevation in liver enzymes (ALT, AST, and LDH) and curbed the Con A-induced hepatocyte necrosis and apoptosis together with abrogating the death pathway, JNK. Coincidentally, escin has shown a reduction in neutrophil, CD4+ T cell, and monocyte infiltration into the liver. In addition, escin modulated the cellular oxidant status by compensating for the Con A-depleted expression of the transcription factor Nrf2 and the stress protein hemeoxygenase-1. These effects were in good agreement with the restraining effect of escin on Con A-instigated overexpression of NF-κB and the pro-inflammatory cytokines TNF-α and IL-17A. Interestingly, Con A provoked the cellular protective pathway IL-22/STAT3, which was revoked by the escin pretreatment. In conclusion, escin shows extended antioxidant, anti-inflammatory, antinecrotic, and anti-apoptotic effects against Con A-induced immune-mediated hepatitis. These effects may collectively be via suppressing immune cell infiltration into the liver and selective modulation of Nrf2/HO-1, TNF-α/NF-κB, TNF-α/JNK, and IL-22/STAT3 signaling pathways.

Background: Lipopolysaccharide (LPS) is a glycolipid that constitutes the Gram-negative bacteria outermost membrane main portion. LPS is frequently of concern in medicine because of nearly all severe sepsis patients have elevated LPS plasma levels, which cause life-threatening organ dysfunction. Consequently, the potential protective benefit of acriflavine (Ac) in limiting LPS-induced acute inflammatory response and the possible underlying mechanisms were investigated. Methods: Male a lbino mice were treated with i.p . Ac 4 or 8 mg/kg/day for 2 weeks, then received a single i.p . LPS (10 mg/kg) at day 14. Results: Ac administration ameliorated hepatic, pulmonary, and testicular dysfunction, as confirmed by attenuation of pathological changes and amendment of oxidative stress parameters. This was associated with inhibition of protein kinase R-like endoplasmic reticulum kinase/phosphatidylinositol 3-kinase (PERK/PI3K) endoplasmic reticulum (ER) stress pathway; toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) and active caspase-1/gasdermin D (GSDMD)-N-terminal as well as interleukin-1 beta (IL-1β) inflammatory and pyroptotic signals. Conclusion: Our results highlighted the protective potential of Ac in a mouse model of LPS-mediated systemic inflammatory response, which paves the way for its clinical application in sepsis.