Pre-conditioning with tanshinone IIA attenuates the ischemia/reperfusion injury caused by liver grafts via regulation of HMGB1 in rat Kupffer cells

Abstract

Objective: We have evaluated the protective mechanism of tanshinone IIA in ischemia/reperfusion injury (IRI) induced by liver grafts, revealing novel supplementary immunotherapy for liver transplantation.

Methods: The tanshinone IIA preconditioning group (TP group) was pretreated with tanshinone IIA via intraperitoneal injection for 1 week before receiving orthotopic liver transplantation with hepatic arterial ischemia for 30min. The sham-operation group (SO group), control graft group (CG group) and IRI group were pretreated with an equivalent volume of normal saline. The IRI group and CG group received orthotopic liver transplantation with or without hepatic arterial ischemia. Rats were sacrificed at each time point, serum was collected for ELISA detection, and Kupffer cells (KCs) were isolated to extract total protein and RNA for western blotting and real-time PCR, respectively.

Results: The levels of TNF-α and IL-4 in the TP group were significantly lower than those of in the IRI group; meanwhile the IL-10 and TGF-β levels were significantly higher than in the IRI group. The protein and mRNA expression levels of HMGB1 were significantly lower in TP group than in the IRI group at each time point. The TLR-4, Myd88, NLRP3 and p-NF-κb p65 expression levels in the TP groups were significantly lower than those in the IRI group, while the PTEN, PI3K and AKT phosphorylation levels in the TP groups were significantly higher than those in the IRI group.

Conclusions: Tanshinone IIA attenuates IRI caused by liver grafts via down-regulation of the HMGB1-TLR-4/NF-κb pathway in KCs and activation of PTEN/PI3K/AKT pathway, suggesting a potential role for prevention of liver cell IRI during liver transplantation.

Keywords: HMGB1; Ischemia reperfusion injury; Kupffer cells; Liver transplantation; Tanshinone IIA.