Protection of Veratrum nigrum L. var. ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver.
OBJECTIVE
To investigate the protective effects and possible mechanisms of Veratrum nigrum L.var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats.


METHODS
Forty male Wistar rats were randomly divided into four experimental groups (n = 10 in each): (A) Control group (the sham operation group); (B) I/R group (pretreated with normal saline); (C) Small-dose (10 microg/kg) VnA pretreatment group; (D) Large-dose (20 microg/kg) VnA pretreatment group. Hepatic ischemia/reperfusion (Hepatic I/R) was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and nitric oxide (NO) content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin (ES) were detected by immunohistochemical examinations and Western blot analyses.


RESULTS
The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase (ALT: 74.53 +/- 2.58 IU/L vs 1512.54 +/- 200.76 IU/L, P < 0.01) and lactic dehydrogenase (LDH: 473.48 +/- 52.17 IU/L vs 5821.53 +/- 163.69 IU/L, P < 0.01), as well as the levels of MPO (1.97 +/- 0.11 U/g vs 2.57 +/- 0.13 U/g, P < 0.01) and NO (69.37 +/- 1.52 micromol/g protein vs 78.39 +/- 2.28 micromol/g protein, P < 0.01) in the liver tissue, all of which were reduced by pretreatment with VnA, respectively (ALT: 1512.54 +/- 200.76 IU/L vs 977.93 +/- 89.62 IU/L, 909.81 +/- 132.76 IU/L, P < 0.01, P < 0.01; LDH: 5821.53 +/- 163.69 IU/L vs 3015.44 +/- 253.01 IU/L, 2448.75 +/- 169.4 IU/L, P < 0.01, P < 0.01; MPO: 2.57 +/- 0.13 U/g vs 2.13 +/- 0.13 U/g, 2.07 +/- 0.05 U/g, P < 0.01, P < 0.01; NO: 78.39 +/- 2.28 micromol/g protein vs 71.11 +/- 1.73 micromol/g protein, 68.58 +/- 1.95 micromol/g protein, P < 0.05, P < 0.01). The activity of SOD (361.75 +/- 16.22 U/mg protein vs 263.19 +/- 12.10 U/mg protein, P < 0.01) in the liver tissue was decreased after I/R, which was enhanced by VnA pretreatment (263.19 +/- 12.10 U/mg protein vs 299.40 +/- 10.80 U/mg protein, 302.09 +/- 14.80 U/mg protein, P < 0.05, P < 0.05). Simultaneously, the histological evidence of liver hemorrhage, polymorphonuclear neutrophil infiltration and the overexpression of ICAM-1 and E-selectin in the liver tissue were observed, all of which were attenuated in the VnA pretreated groups.


CONCLUSIONS
The results demonstrate that VnA pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of antioxidant capacity, reduction of inflammatory responses and suppressed expression of ICAM-1 and E-selectin.
Wang
Zhen-Zhen
ZZ
Department of Pharmacology, Dalian Medical University, Dalian 116027, Liaoning Province, China.
Zhao
Wei-Jie
WJ
Zhang
Xue-Song
XS
Tian
Xiao-Feng
XF
Wang
Yu-Zhu
YZ
Zhang
Feng
F
Yuan
Jin-Chan
JC
Han
Guo-Zhu
GZ
Liu
Ke-Xin
KX
Yao
Ji-Hong
JH
D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D015153:Blotting, Western; D019040:E-Selectin / Q000032:analysis; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008099:Liver / Q000098:blood supply* / Q000473:pathology; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000517:prevention & control*; D013482:Superoxide Dismutase / Q000378:metabolism; D014704:Veratrum Alkaloids / Q000627:therapeutic use*
D019040:E-Selectin; D014704:Veratrum Alkaloids; D018799:Intercellular Adhesion Molecule-1; D009569:Nitric Oxide; D007770:L-Lactate Dehydrogenase; D009195:Peroxidase; D013482:Superoxide Dismutase; D000410:Alanine Transaminase