Gabexate Mesylate-Poloxamer 407 Conjugate Alleviates Sodium Taurocholate-Induced Severe Acute Pancreatitis in an Optimized Rat Model

Background and aims: We have previously shown that gabexate mesylate-poloxamer 407 conjugate (GMTI) alleviates traumatic pancreatitis in rats. In this study, we evaluated the therapeutic effect of GMTI on sodium taurocholate-induced severe acute pancreatitis (SAP) in an optimized rat model.

Methods: An SAP rat model was established via microinjection of 3.5% sodium taurocholate and retention in the bile duct for 1 min. SAP rats were administered GMTI via tail vein injection (i.v.) or tail vein injection + intraperitoneal injection (i.v. + i.p.). All rats were sacrificed at 12 h after treatment. Biochemical approach and enzyme-linked immunosorbent assay were performed to measure the serum levels of amylase (AMY), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Hematoxylin and eosin staining and TUNEL assay were conducted to examine histopathology and acinar cell apoptosis in the rat pancreas.

Results: SAP was successfully induced in all model rats, as evidenced by progressively aggravating SAP symptoms and signs, pancreatic histopathological abnormalities, as well as elevated serum levels of TNF-α, IL-6, and AMY. The mortality rates at 1 h, 6 h, and 12 h were 0%, 0%, and 25%, respectively. GMTI therapy via i.v. or i.v. + i.p. significantly reduced pancreatic wet weights, ascites amounts, pathological scores, and circulating levels of TNF-α and IL-6 while promoting acinar cell apoptosis in SAP rats. GMTI therapy via i.v. + i.p. outperformed i.v. in improving pancreatic histology and reducing TNF-α and IL-6 serum levels in SAP rats.

Conclusions: Our optimized SAP rat model is reliable and reproducible. GMTI therapy is a promising approach against SAP.