Objective: To observe the effect of thymosin alpha l (Tα1) on severe acute pancreatitis (SAP) in rats.

Methods: Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups (eight in each group): control group (Group A), SAP group (Group B) and Tα1 treatment group (Group C). Animal models of SAP were made by retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. Rats in Group C were treated with Tα1 (6 mg/kg) via intraperitoneal administration prior to SAP modelling. Eight rats in each group were sacrificed at 12 hours, respectively, after modelling. The serum levels of amylase, tumour necrosis factor-α (TNF-α), interleukin-lβ (IL-lβ) and interleukin-6 (IL-6) were detected in each group. The pathological scores of the tissue in the pancreas head were observed by light microscopy.

Results: The levels of serum amylase of Group B were 6378 ± 538 U/L, which were significantly higher than those (4587 ± 478 U/L) of Group C (p < 0.05). The levels of serum TNF-α of Group B were 360.32 ± 28.67 pg/mL, which were higher than those (269.99 ± 26.11 pg/mL) of Group C (p < 0.05). The levels of serum IL-lβ of Group B were 435.93 ± 36.00 pg/mL, which were higher than those (312.42 ± 17.89 pg/mL) of Group C (p < 0.05). The levels of serum IL-6 of Group B were 433.90 ± 28.36 pg/mL, which were higher than those (289.98 ± 23.00 pg/mL) of Group C (p < 0.05). The pancreatic pathological scores of Group B were 13.34 ± 2.19, which were higher than those (6.39 ± 1.86) of Group C (p < 0.05).

Conclusion: Thymosin alpha 1 could decrease proinflammatory cytokines and reduce pancreas injury and had a protective effect in rats with SAP. This provides a new strategy for the clinical treatment of SAP.