Anti-hemorrhoidal activity of Lian-Zhi-San, a traditional Chinese medicine, in an experimental hemorrhoidal model in rats

Objective: Hemorrhoidal disease (HD) is the most common proctological disease, with an estimated prevalence rate of 4.4%, and a peak in individuals between 45 and 65 years of age. This study was done to evaluate whether Lian-Zhi-San (LZS), a clinically used anti-hemorrhoidal ointment could alleviate the inflammatory injury, with its associated changes of inflammatory cytokines and morphology of anorectal tissues, in an experimental model of HD in rats.

Methods: HD was induced by croton oil preparation (COP) applied to the anorectal region. Rats were then treated with cotton swabs soaked in LZS ointment, water or white vaseline, twice a day for 7 d. At the end of the experiment, HD was evaluated by measuring hemorrhoidal and biochemical parameters along with histopathological observations.

Results: In this study, COP induced a significant increase in the macroscopic severity score, anorectal coefficient and Evans blue extravasation, compared to normal rats. Additionally, it greatly enhanced the expression and secretion levels of some important inflammation-related cytokines along with marked histological damage, compared to normal rats. Rats treated with LZS ointment experienced significantly ameliorated Evans blue extravasation (P < 0.05), decreased macroscopic severity score (0.86 ± 0.14 vs. 1.65 ± 0.16) and the anorectal coefficient (P < 0.01); its use also attenuated tissue damage and inhibited the expression and secretion levels of inflammation-related cytokines (interleukin-1β, interleukin-6 and tumor necrosis factor-α).

Conclusion: This study validates a preliminary understanding of the use of LZS ointment to treat inflammatory factors and tissue damage in an experimental model of HD in rats.