Haemoxygenase modulates cytokine induced neutrophil chemoattractant in hepatic ischemia reperfusion injury

Transcriptional changes in orthotopic liver transplantation and ischemia/reperfusion injury

Background There are few effective targeting strategies to reduce liver ischemia-reperfusion injury (IRI), which is one of the reasons for the poor prognosis of liver transplant recipients. Methods A systematic approach combining gene expression with protein interaction (PPI) network was used to screen the characteristic genes and related biological functions of post-transplant. Differentially expressed genes (DEGs) between IRI+ and IRI- were identified. Logistic regression model and receiver operating characteristic (ROC) curve were used to identify potential target genes of IRI. The expression of key genes was verified by qRT-PCR and Western-blot experiments. Finally, the ssGSEA was used to identify the immune cell infiltration in patients with IRI. Results The 283 common DEGs in GSE87487 and GSE151648 were mainly related to apoptosis and IL-17 signaling pathway. Through PPI network and logistic regression analysis, we identified that IL6, CCL2 and CXCL8 may be involved in the ischemia/reperfusion (IR) process. In addition, 32 genes were showed associated with IRI through inflammatory and metabolic pathways. Among the key genes identified, the differential expression of AGBL4, CILP2 and IL4I1 was verified by molecular experiments. Th17 cells of differentially infiltrated immune cells were positively correlated with CILP2 and IL4I1. The difference of Th17 cells between IRI+ and IRI- was verified by flow cytometry. Conclusion The study showed that AGBL4, CILP2 and IL4I1 were associated with IRI. Th17 cells may be associated with the regulation of IRI by key genes. These genes and related pathways may be targets for improving IRI.

Topical hepatic hypothermia associated with ischemic preconditioning. Histopathological and biochemical analysis of ischemia reperfusion damage in a 24 hour model 1

PURPOSE

To develop a new 24 hour extended liver ischemia and reperfusion (LIR) model analyzing the late biochemical and histopathological results of the isolated and combined application of recognized hepatoprotective mechanisms. In addition, we used a new stratification with zoning to classify the histological lesion.

METHODS

A modified animal model of severe hepatic damage produced through 90 minutes of segmental ischemia (70% of the organ) and posterior observation for 24 hours of reperfusion, submitted to ischemic preconditioning (IPC) and topical hypothermia (TH) at 26ºC, in isolation or in combination, during the procedure. Data from intraoperative biometric parameters, besides of late biochemical markers and histopathological findings, both at 24 hours evolution time, were compared with control (C) and normothermic ischemia (NI) groups.

RESULTS

All groups were homogeneous with respect to intraoperative physiological parameters. There were no losses once the model was stablished. Animals subjected to NI and IPC had worse biochemical (gamma-glutamyl transpeptidase, alkaline phosphatase, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, direct bilirubin, and total bilirubin) and histopathological scores (modified Suzuki score) compared to those of control groups and groups with isolated or associated TH (p < 0.05).

CONCLUSION

The new extended model demonstrates liver ischemia and reperfusion at 24 hour of evolution and, in this extreme scenario, only the groups subjected to topical hypothermia, combined with ischemic preconditioning or alone, had better outcomes than those subjected to only ischemic preconditioning and normothermic ischemia, reaching similar biochemical and histopathological scores to those of the control group.

Comparison of hepatoprotective effect from ischemia-reperfusion injury of remote ischemic preconditioning of the liver vs local ischemic preconditioning of the liver during human liver resections

AIM

To compare and evaluate the hepatoprotective effect of remote ischemic preconditioning (RIPC) with local ischemic preconditioning (LIPC) of the liver during human liver resections.

METHODS

A prospective, single-centre, randomised control trial was conducted in the Clinical Hospital "***" from April 2017 to January 2018. A total of 60 patients, who underwent liver resection due to colorectal cancer liver metastasis, were randomised to one of three study arms: 1) a RIPC group, 2) an LIPC group and 3) a control group (CG) in which no ischemic preconditioning was done before liver resection. The hepatoprotective effect was evaluated by comparing serum transaminase levels, bilirubin levels, albumin, and protein levels, coagulograms and through pathohistological analysis. The trial was registered on ClinicalTrials.gov (NCT****).

RESULTS

Significant differences were found in serum levels of liver transaminases and bilirubin levels between thegroups, the highest level in the CG and the lowest level in the LIPC group. Levels of cholinesterase were also significantly higher in the LIPC group. Pathohistological findings graded by the Rodriguez score showed favourable changes in the LIPC and RIPC groups versus the CG.

CONCLUSION

Strong evidence supports the hepatoprotective effect of RIPC and LIPC preconditioning from an ischemia-reperfusion injury of the liver. Better synthetic liver function preservation in these two groups supports this conclusion.

Hydrogen-Rich Saline Ameliorates Hepatic Ischemia-Reperfusion Injury Through Regulation of Endoplasmic Reticulum Stress and Apoptosis

OBJECTIVE

To evaluate the effect of hydrogen-rich saline (HS) on hepatic ischemia-reperfusion (I/R) injury.

METHODS

Forty rats were randomly allocated into five groups: one sham group (control group), one group treated with 20 min of ischemia and normal saline (NS; I/R1 + NS group), one group treated with 20 min of ischemia and HS (I/R1 + HS group), one group treated with 60 min of ischemia and NS (I/R2 + NS group), and one group treated with 60 min of ischemia and HS (I/R2 + HS group). After reperfusion for 6 h, hepatic function, oxidative stress, pathological changes, and apoptosis of hepatic cells were evaluated. Furthermore, the expression levels of endoplasmic reticulum (ER) stress-associated proteins were identified.

RESULTS

Serum ALT and AST levels and tissue MDA content in the I/R + HS groups were significantly lower than those in the I/R + NS groups. Pathological changes were also significantly ameliorated in the HS groups compared with those in the NS groups. Moreover, HS appeared to significantly attenuate hepatic I/R-induced ER stress responses, as indicated by the decreased expression of C/EBP homologous protein, protein-kinase-RNA-like ER kinase, and inositol-requiring protein-1α, as well as the increased expression of GRP78 proteins. Finally, the levels of apoptotic markers such as caspase-3 and TUNEL-positive cells were significantly lower in the HS groups than in the NS control groups, whereas the level of Bcl2 protein increased in the HS groups.

CONCLUSION

The protective effect of HS can be attributed to ER stress and apoptosis inhibition.

The mechanism of long non-coding RNA MEG3 for hepatic ischemia-reperfusion: Mediated by miR-34a/Nrf2 signaling pathway

To investigate the function of MEG3 in hepatic ischemia-reperfusion (HIR) progress, involving its association with the level of miR-34a during hypoxia-induced hypoxia re-oxygenation (H/R) in vitro. HIR mice model in vivo was established. MEG3, miR-34a expression, along with Nrf2 mRNA and protein level were detected in tissues and cells. Serum biochemical parameters (ALT and AST) were assessed in vivo. A potential binding region between MEG3 and miR34a was confirmed by luciferase assays. Hepatic cells HL7702 were subjected to hypoxia treatment in vitro for functional studies, including TUNEL-positive cells detection and ROS analysis. MEG3, Nrf2 expression was significantly down-regulated in infarction lesion from HIR mice, as opposed to increased miR-34a production, while similar results were also observed in H/R HL7702 cells, while the above effects were reversed by MEG3 over-expression. By using bioinformatics study and RNA pull down combined with luciferase assays, we demonstrated that MEG3 functioned as a competing endogenous RNA (ceRNA) for miR-34a, and there was reciprocal repression between MEG3 and miR-34a in an Argonaute 2-dependent manner. Functional studies demonstrated that MEG3 showed positive regulation on TUNEL-positive cells and ROS level. Further in vivo study confirmed that MEG3 over-expression could improve hepatic function of HIR mice, and markedly decreased the expression of serum ALT and AST. MEG3 protected hepatocytes from HIR injury through down-regulating miR-34a expression, which could add our understanding of the molecular mechanisms in HIR injury.