Protective effect of thymosin β4 on severe acute pancreatitis in rats / 中华急诊医学杂志

ABSTRACT

Objective To investigate the protective effects and mechanisms of intraperitoneal administration of thymosin β4 on severe acute pancreatitis in rats.Methods Fifty-four male Sprague-Dawley rats were randomly (random number) divided into sham operation (SO) group,severe acute pancreatitis (SAP) group and thymosin β4 (Tβ4) pretreatment group (n =18 in each group).SAP rat model was prepared by retrograde injection of 5％ sodium taurocholate into the biliopancreatic duct.Rats in Tβ4 group were treated with thymosin β4 (6 mg/kg) by intraperitoneal administration prior to SAP modeling.Six rats in each group were sacrificed at 3,6,12 hours,respectively after modeling.The serum levels of amylase,tumor necrosis factor-α (TNF-α),interleukin-1 β (IL-1 β),and interleukin-6 (IL-6)were detected,and pathological scores of the tissue of pancreas head were evaluated under light microscope.Pancreatic nuclear factor-kappa 1B (NF-κB) p65 and IκB α levels were detected by the Western blot.All data were analyzed by using the analysis of variauce or t test.Results The levels of serum amylase of SAP 3,6 and 12 hours groups were (3221 ±394) U/L,(4509 ±474) U/L and (6280 ±728) U/L,which were significantly higher than (2598±416) U/L,(3639 ±373) U/L and (4782 ±466) U/L of the Tβ4 groups (t =-2.666,-3.530,-4.245,P ＜ 0.05).The levels of serum TNF-α of the SAP 3,6 and 12 hours groups were (247.7 ± 18.5) pg/mL,(313.5 ± 17.7) pg/mL and (359.3 ±22.6) pg/mL,which were higher than (182.3 ± 13.6) pg/mL,(258.9 ± 14.9) pg/mL and (278.1 ± 16.3) pg/mL of the Tβ4 groups (t =-6.964,-5.769,-7.152,P ＜ 0.05).The levels of serum IL-1 β of the SAP 3,6 and 12 hours groups were (258.2±10.5) pg/mL,(345.1 ±22.0) pg/mL and (430.9 ±25.4) pg/mL,which were higher than (170.3 ± 12.4) pg/mL,(263.5 ± 13.3) pg/mL and (303.7 ± 16.1) pg/mL of the Tβ4 groups (t =-13.258,-7.762,-10.355,P ＜ 0.05).The levels of serum IL-6 of SAP 3,6 and 12 hours groups were (266.3 ±11.5) pg/mL,(355.0 ±24.4) pg/mL and (429.2 ±33.7) pg/ mL,which were higher than (171.1 ± 13.0) pg/mL,(234.9 ± 19.2) pg/mL and (277.2 ± 19.2) pg/ mL of the Tβ4 groups (t =-13.401,-9.474,-9.582,P ＜ 0.05).The pancreatic pathological scores of the SAP3,6 and 12 hours groups were (6.25 ±0.94),(8.83 ±0.82) and (12.08 ±1.16),which were higher than (4.17 ± 0.93),(6.33 ± 0.82) and (7.33 ± 1.25) of the Tβ4 groups (t =-3.867,-5.303,-6.823,P ＜ 0.05).The relative expression of pancreatic NF-κB p65 in SO group was (0.95 ±0.11),which was significantly lower than (2.40 ±0.17) of the SAP 12 hours group (t =-17.368,P＜ 0.05).The relative expression of pancreatic NF-κB p65 in Tβ4 group was 1.50 ± 0.10,which was significantly lower than SAP 12 hours group (t =10.917,P ＜0.05).The relative expression of pancreatic IκB α in SO group was (1.93 ±0.11),which was significantly higher than (0.78 ±0.18) of the SAP 12 hours group (t =13.260,P ＜ 0.05).The relative expression of pancreatic IκB α in Tβ4 group was (1.12±0.10),which was significantly higher than SAP 12 hours group (t =-4.112,P ＜ 0.05).Conclusions Thymosin β4 has the protective effect on SAP rat model,and the mechanism may be associated with inhibition of NF-κB signaling pathway and decreased proinflammatory cytokines.