Hepatoprotective Effects of Spirulina Preconditioning Against Ischemia–Reperfusion Injury in Steatotic Livers

Hepatic ischemia–reperfusion (IR) injury is a significant clinical complication, particularly in steatotic livers, which are highly susceptible to oxidative and inflammatory cascades. This study evaluated whether spirulina (Arthrospira platensis) could attenuate IR-induced damage exacerbated by dietinduced steatosis in rats. The study was conducted in accordance with the Declaration of Helsinki and approved by the Research Ethics Committee for Life and Health Sciences of the Higher Institute of Biotechnology of Monastir-Tunisia (Approval reference: CER-SVS/ISBM 012/2024, approval date: 15 February 2025). Male Wistar rats were divided into five groups: sham, IR, high-fat diet (HFD), HFD + IR, and a group treated with 1000 mg/kg/day of spirulina (SP1000), through oral gavage in random order and at the same time each day, for three weeks. Liver injury was assessed through serum transaminases (ALT, AST), histological analysis (Suzuki and steatosis scores), immunofluorescence assay, and markers of oxidative stress, inflammation, and inflammasome/ pyroptosis signaling. Steatosis significantly worsened IR outcomes, leading to higher transaminase release, enhanced oxidative stress (increased Malondialdehyde and decreased Superoxide Dismutase/Reduced Glutathione), and activation of inflammatory (TLR4, NF-κB, TNF-α, IL-1β) and inflammasome (NLRP3, IL-18, GSDMD) pathways. Spirulina supplementation markedly mitigated these effects, preserving hepatic architecture and restoring antioxidant defenses. Mechanistically, spirulina downregulated pro-inflammatory and pyroptotic gene expression while shifting lipid metabolism markers toward control levels. These findings suggest that spirulina preconditioning is a viable nutritional approach to protect steatotic livers from IR injury by suppressing oxidative stress, downregulating inflammation, and inflammasome-mediated cell death.