Effects of IL-10 on serum TNF-α and pancreatic tissue in rats with severe acute pancreatitis

Objective To investigate the effects of recombinant human interleukin-10 (IL-10) on serum tumor necrosis factor α (TNF-α) and histopathological changes of pancreas in rats with severe acute pancreatitis (SAP), and provide theorical basis for SAP clinical treatment. Methods 90 Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (group N, n=30), SAP group (group S, n=30) and IL-10 interference group (group I, n=30). 5% sodium taurocholate was retrogradely injected into the pancreatic duct in S group and I group to induce SAP model. Rats in N group whose pancreas was just flipped and stricken gently without injection. Group I was treated with 10 000 units of intrape-ritioneal recombinant human IL-10 at 1, 3 and 5 h. Group N and group S received three intraperitoneal injections of 0.9% normal saline at the same time points. Rats were killed at 6, 12 and 24 h. The level of TNF-α in serum was determined by enzyme-linked immunosorbent assay (ELISA), and the level of amylase was assayed by biochemical methods. The pancreas histological changes were observed by H-E staining. Results Compared with group N [serum amylase (1 025.3±326.9), (999.9±212.3), (962.3±128.9) IU/L; TNF-α (55.6±2.1), (56.1±2.2), (58.7±1.3)ng/L; pancreatic histopathological score 0.13±0.11, 0.15±0.12, 0.16±0.15], serum amylase (6 633.9±846.7), (9 421.4±1 031.8), (8 755.6±734.5) IU/L, TNF-α (87.6±3.3), (113.3±10.2), (100.2±2.3) ng/L and pancreatic histopathological score (8.58±0.63, 13.41±0.79, 16.78±0.87) in group S were increased significantly at 6, 12 and 24 h (P<0.05). The pancreatic damage at 24 h was the most severe, and the peak concentration of AMY and TNF-α reached at 12 h. Compared with group S, pancreatic histopathological scores 6.52±0.54, 9.37±0.35, 12.43±0.69, the level of serum amylase (6 032.8±534.9), (7 475.8±834.2), (6 903.4±377.1) IU/L and TNF-α (67.5±2.5), (93.0±4.9), (86.7±6.6) ng/L in group I were significantly decreased at corresponding time points (P<0.05). Conclusions Early application of recombinant human IL-10 can attenuate SAP inflammatory response and relieve the histopathological injury of pancreas by inhibiting the release of TNF-α. IL-10 can be used for the treatment of SAP. Key words: Severe acute pancreatitis; Interleukin-10; Tumor necrosis factor-α; Rat