Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 7, 2016; 22(33): 7518-7535
Published online Sep 7, 2016. doi: 10.3748/wjg.v22.i33.7518
Haemoxygenase modulates cytokine induced neutrophil chemoattractant in hepatic ischemia reperfusion injury
Niteen Tapuria, Sameer Junnarkar, Mahmoud Abu-amara, Barry Fuller, Alexander M Seifalian, Brian R Davidson
Niteen Tapuria, Sameer Junnarkar, Mahmoud Abu-amara, Barry Fuller, Alexander M Seifalian, Brian R Davidson, Department of HPB Surgery and Liver transplantation, Royal Free Hospital, London NW32QG, United Kingdom
Author contributions: Tapuria N performed the majority of experiments and wrote the manuscript; Junnarkar S helped with experiments and sample collection; Abu-amara M helped with analysis; Fuller B performed literature review; Seifalian AM coordinated the research; and Davidson BR supervised the research.
Supported by Peter Samuel Grant, Royal Free NHS trust United Kingdom.
Institutional review board statement: This study has been reviewed by the Royal Free research committee and approved.
Institutional animal care and use committee statement: All experiments were conducted under project license from home office United Kingdom in accordance with the animals’ scientific act 1986. All animals were treated in accordance with the guidelines issued by the home office.
Conflict-of-interest statement: No conflict of interest.
Data sharing statement: No additional data available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Niteen Tapuria, MS, MD (research), FRCS, FRCS (Gen Surg), Department of HPB Surgery and Liver transplantation, Royal Free Hospital, Hampstead, London NW32QG, United Kingdom. ntapuria@yahoo.com
Telephone: +44-774-7623541
Received: September 27, 2015
Peer-review started: September 28, 2015
First decision: November 27, 2015
Revised: February 5, 2016
Accepted: May 21, 2016
Article in press: May 23, 2016
Published online: September 7, 2016
Processing time: 343 Days and 13 Hours
Abstract
AIM

To investigate the hepatic microcirculatory changes due to Haemoxygenase (HO), effect of HO inhibition on remote ischemic preconditioning (RIPC) and modulation of CINC.

METHODS

Eight groups of animals were studied - Sham, ischemia reperfusion injury (IRI) the animals were subjected to 45 min of hepatic ischemia followed by three hours of reperfusion, RIPC (remote ischemic preconditioning) + IRI group, remote ischemic preconditioning in sham (RIPC + Sham), PDTC + IR (Pyridodithiocarbamate, HO donor), ZnPP + RIPC + IRI (Zinc protoporphyrin prior to preconditioning), IR-24 (45 min of ischemia followed by 24 h of reperfusion), RIPC + IR-24 (preconditioning prior to IR). After 3 and 24 h of reperfusion the animals were killed by exsanguination and samples were taken.

RESULTS

Velocity of flow (160.83 ± 12.24 μm/s), sinusoidal flow (8.42 ± 1.19) and sinusoidal perfusion index (42.12 ± 7.28) in hepatic IR were lower (P < 0.05) in comparison to RIPC and PDTC (HO inducer). RIPC increased velocity of flow (328.04 ± 19.13 μm/s), sinusoidal flow (17.75 ± 2.59) and the sinusoidal perfusion index (67.28 ± 1.82) (P < 0.05). PDTC (HO induction) reproduced the effects of RIPC in hepatic IR. PDTC restored RBC velocity (300.88 ± 22.109 μm/s), sinusoidal flow (17.66 ± 3.71) and sinusoidal perfusion (82.33 ± 3.5) to near sham levels. ZnPP (HO inhibition) reduced velocity of flow of RBC in the RIPC group (170.74 ± 13.43 μm/s and sinusoidal flow in the RIPC group (9.46 ± 1.34). ZnPP in RIPC (60.29 ± 1.82) showed a fall in perfusion only at 180 min of reperfusion. Neutrophil adhesion in IR injury is seen in both postsinusoidal venules (769.05 ± 87.48) and sinusoids (97.4 ± 7.49). Neutrophil adhesion in RIPC + IR injury is reduced in both postsinusoidal venules (219.66 ± 93.79) and sinusoids (25.69 ± 9.08) (P < 0.05). PDTC reduced neutrophil adhesion in both postsinusoidal venules (89.58 ± 58.32) and sinusoids (17.98 ± 11.01) (P < 0.05) reproducing the effects of RIPC. ZnPP (HO inhibition) increased venular (589.04 ± 144.36) and sinusoidal neutrophil adhesion in preconditioned animals (121.39 ± 30.65) (P < 0.05). IR after 24 h of reperfusion increased venular and sinusoidal neutrophil adhesion in comparison to the early phase and was significantly reduced by RIPC. Hepatocellular cell death in IRI (80.83 ± 13.03), RIPC + IR (17.35 ± 2.47), and PTDC + IR (11.66 ± 1.17) reduced hepatocellular death. ZnPP + RIPC + IR (41.33 ± 3.07) significantly increased hepatocellular death (P < 0.05 PTDC/RIPC vs ZnPP and IR). The CINC cytokine levels in sham (101.32 ± 6.42). RIPC + sham (412.18 ± 65.24) as compared to sham (P < 0.05). CINC levels in hepatic IR were (644.08 ± 181.24). PDTC and RIPC CINC levels were significantly lower than hepatic IR (P < 0.05). HO inhibition in preconditioned animals with Zinc protoporphyrin increased serum CINC levels (521.81 ± 74.9) (P < 0.05). The serum CINC levels were high in the late phase of hepatic IR (15306 ± 1222.04). RIPC reduced CINC levels in the late phase of IR (467.46 ± 26.06), P < 0.05.

CONCLUSION

RIPC protects hepatic microcirculation by induction of HO and modulation of CINC in hepatic IR.

Keywords: Reperfusion injury; CINC; Microcirculation; Ischemic preconditioning; Remote preconditioning; Haemoxygenase

Core tip: This study is novel in demonstrating the in vivo microcirculatory changes due to haemoxygenase (HO) induced by Remote ischemic preconditioning by brief hind limb ischemia (RIPC) in hepatic ischemia reperfusion (IR) injury. HO also decreased CINC levels (cytokine secreted from kupffer cells in hepatic IR) which is significant in reducing neutrophil recruitment and IR injury. HO inhibition abolished the protective effect of RIPC on hepatic microcirculation and was associated with significantly elevated CINC levels, serum transaminases and hepatocellular death. These findings are novel and have not been demonstrated in previous studies. RIPC may have a potential role in donor preconditioning.