Effect of Herbal Medicine Keishi-to (TJ-45) and Its Components on Rat Pancreatic Acinar Cell Injuries in Vivo and in Vitro

Background: In an attempt to clarify the mechanism of the effect of a herbal medicine, Saiko-keishi-to (TJ-10), which is a combination of Keishi-to (TJ-45) and Sho-saiko-to (TJ-9), we investigated the effects of these two herbal medicines and their components on pancreatic acinar cell injury models in vivo and in vitro.

Methods: Four-week-old male WBN/Kob rats were fed an MB-3 pellet diet containing herbal medicine (TJ-9, TJ-10 and TJ-45). Expressions of pancreatitis-associated protein (PAP) and manganese superoxide dismutase (Mn-SOD) were analyzed with a reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. The herbal medicines and two of their components, Keihi (Cinnamomi cortex) and Shakuyaku (Paeoniae radix alba), were tested in vitro using an arginine-treated rat pancreatic acinar AR4-2J cell injury model. The inducible nitric oxide synthase (iNOS) was assayed in in vitro experiments.

Results: TJ-45-treated WBN/Kob rats showed no evidence of pancreatitis whereas there were pathological changes of chronic pancreatitis in TJ-9-treated WBN/Kob rats. PAP was not expressed and Mn-SOD expression was increased in the TJ-10-, and TJ-45-treated rats. The herbal medicines and two components suppressed PAP mRNA expression and enhanced Mn-SOD and iNOS mRNA expression in arginine-treated AR4-2J cells.

Conclusion: These results suggest that the herbal medicine TJ-45 is effective for chronic pancreatitis caused by pancreatic ischemia.