Published online Dec 7, 2015. doi: 10.3748/wjg.v21.i45.12778
Peer-review started: June 19, 2015
First decision: July 10, 2015
Revised: July 22, 2015
Accepted: September 15, 2015
Article in press: September 15, 2015
Published online: December 7, 2015
Processing time: 173 Days and 3.5 Hours
AIM: To investigate the cytoprotective effects in hepatic ischemia-reperfusion injury, we developed a new formulation of hyaluronic acid (HA) and sphingosine 1-phophate.
METHODS: We divided Sprague-Dawley rats into 4 groups: control, HA, sphingosine 1-phosphate (S1P), and HA-S1P. After the administration of each agent, we subjected the rat livers to total ischemia followed by reperfusion. After reperfusion, we performed the following investigations: alanine aminotransferase (ALT), histological findings, TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining, and transmission electron microscopy (TEM). We also investigated the expression of proteins associated with apoptosis, hepatoprotection, and S1P accumulation.
RESULTS: S1P accumulated in the HA-S1P group livers more than S1P group livers. Serum ALT levels, TUNEL-positive hepatocytes, and expression of cleaved caspase-3 expression, were significantly decreased in the HA-S1P group. TEM revealed that the liver sinusoidal endothelial cell (LSEC) lining was preserved in the HA-S1P group. Moreover, the HA-S1P group showed a greater increase in the HO-1 protein levels compared to the S1P group.
CONCLUSION: Our results suggest that HA-S1P exhibits cytoprotective effects in the liver through the inhibition of LSEC apoptosis. HA-S1P is an effective agent for hepatic ischemia/reperfusion injury.
Core tip: We have developed a new formulation by directly combining hyaluronic acid and sphingosine 1-phosphate (HA-S1P), which targets liver sinusoidal endothelial cell (LSEC) by binding specifically to HA and HA receptors. This study demonstrated that HA-S1P protects the liver from hepatic ischemia/reperfusion (I/R) injury in rats. The strong protective effect of HA-S1P may be mediated by the anti-apoptotic effect of S1P on LSECs. These data indicate that HA-S1P is an effective agent for preventing hepatic I/R injury.