Sishen Pill (SSP) is a classical prescription of
traditional Chinese medicine and often used to treat
gastrointestinal diseases, including
ulcerative colitis (UC). However, its mechanism is still unclear. We aimed to determine the mechanism of SSP in the treatment of UC by investigating if it maintains the integrity of the intestinal mucosal barrier via the Rho A/
Rho kinase (ROCK) signaling pathway. Administration of
2,4,6-trinitrobenzene sulfonic acid (TNBS) successfully induced chronic UC in rats, while the treatment effect of SSP was evaluated by
body weight change, colonic length, colonic weight, colonic weight index, histological injury score, and pathological injury score after
colitis rats were treated for 7 days. TNF-α and IL-1β levels were analyzed by ELISA, and the
proteins of PI3K/Akt and RhoA/ROCK signaling pathway and junction
proteins expression were measured by western blotting assay, and the distribution of
Claudin 5 was shown by immunofluorescence. SSP significantly improved the clinical symptoms of
colitis in rats and reduced the expression of p-RhoA, ROCK1, PI3K, and Akt in the colon mucosa, while it increased the expression of p-Rac and related
proteins (
Claudin-5, JAM1,
VE-cadherin, and
Connexin 43). In addition, SSP increased p-AMPKα and PTEN
proteins expression, decreased Notch1 level, and hinted that activation of the PI3K/Akt signaling pathway was inhibited. In conclusion, SSP effectively treated chronic
colitis induced by TNBS, which may have been achieved by inhibiting PI3K/Akt signal to suppress activation of the Rho/ROCK signaling pathway to finally maintain the integrity of the intestinal mucosal barrier.