Real-world experience with Curcumin-QingDai combination for patients with active ulcerative colitis: A retrospective multicentre cohort study

Qingchang Wenzhong Decoction ameliorates intestinal inflammation and intestinal barrier dysfunction in ulcerative colitis via the GC-C signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder of the colonic mucosa, accompanied with abdominal pain, and bloody diarrhea. Currently, clinical treatment options for UC are limited. Qingchang Wenzhong Decoction (QCWZD) is an effective prescription of traditional Chinese medicine for the treatment of UC. However, the mechanism of QCWZD in alleviating intestinal barrier dysfunction in UC has not been clearly explained.

AIM OF THE STUDY

To determine the mechanism whereby QCWZD promotes the recovery of intestinal barrier dysfunction in UC.

MATERIALS AND METHODS

A secondary analysis of colonic mucosa from UC patients acquired from a prior RCT clinical trial was performed. The effects of QCWZD on intestinal mucus and mechanical barriers in UC patients were evaluated using colon tissue paraffin-embedded sections from UC patients. The mechanism was further investigated by in vivo and in vitro experiments. UC mice were established in sterile water with 3.0% dextran sodium sulfate (DSS). Meanwhile, mice in the treatment group were dosed with QCWZD or mesalazine. In vitro, an intestinal barrier model was constructed using Caco-2 and HT29 cells in co-culture. GC-C plasmid was used to overexpress/knock down GC-C to clarify the target of QCWZD. HE, AB-PAS, ELISA, immunohistochemistry and immunofluorescence assays were used to assess the level of colonic inflammation and intestinal barrier integrity. Rt-qPCR, Western Blot were used to detect the expression of genes and proteins related to GC-C signaling pathway. Molecular docking was used to simulate the binding sites of major components of QCWZD to GC-C.

RESULTS

In UC patients, QCWZD increased mucus secretion, goblet cell number, and promoted MUC2 and ZO-1 expression. QCWZD accelerated the recovery of UC mice from DSS-induced inflammation, including weight gain, reduced disease activity index (DAI) scores, colon length recovery, and histological healing. QCWZD promoted mucus secretion and increased ZO-1 expression in in vivo and in vitro experiments, thereby repairing mucus mechanical barrier damage. The effects of QCWZD are mediated through regulation of the GC-C signaling pathway, which in turn affects CFTR phosphorylation and MUC2 expression to promote mucus secretion, while inhibiting the over-activation of MLCK and repairing tight junctions to maintain the integrity of the mechanical barrier. Molecular docking results demonstrate the binding of the main components of QCWZD to GC-C.

CONCLUSION

Our study demonstrated that QCWZD modulates the GC-C signaling pathway to promote remission of mucus-mechanical barrier damage in the UC. The clarification of the mechanism of QCWZD holds promise for the development of new therapies for UC.

Indigo naturalis (Qing dai) for inflammatory bowel disease: A systematic review and meta-analysis

BACKGROUND

Indigo naturalis (Qing dai) is a traditional therapy reported to be useful in inflammatory bowel disease (IBD), especially for ulcerative colitis. We performed a systematic review of its efficacy and safety in IBD.

METHODS

Electronic databases (Pubmed, Embase, and Scopus) were searched on 4th March 2023 to identify reports about the use of indigo naturalis in IBD. We extracted data with respect to clinical response, remission, endoscopic and histological responses, and adverse events with the use of indigo naturalis in IBD. Pooled clinical response rates and remission rates were calculated. The quality of studies was assessed using Joanna-Briggs tools.

RESULTS

Nine studies reporting on 299 patients were included. The pooled clinical response rate was 0.796 (95 %CI, 0.7465-0.8379, I2=0), and the clinical remission rate in ulcerative colitis was 0.668 (0.488- 0.809, I2=85.2 %). The pooled relative risk of clinical response was higher in the indigo naturalis group as compared to placebo in the two randomized trials [3.82 (2.04; 7.14, I2=0)]. Except for one reversible pulmonary arterial hypertension case, most reported adverse effects were mild. The endoscopic and histological responses, when reported, suggested that indigo naturalis is effective for ulcerative colitis. The limitations of the systematic review included a small number of randomized studies, reports only from East Asia and a relatively small number of patients, especially for Crohn's disease.

CONCLUSION

Indigo naturalis is effective in the treatment of ulcerative colitis. Future studies should evaluate the comparative efficacy with other drugs.

Letter: Chinese herbal medicine Curcumin-QingDai (CurQD) - A good treatment option for active ulcerative colitis?

This article is linked to Yanai et al papers. To view these articles, visit https://doi.org/10.1111/apt.17538 and https://doi.org/10.1111/apt.17655

Letter: Chinese herbal medicine Curcumin-QingDai (CurQD)-A good treatment option for active ulcerative colitis? Authors' reply

This article is linked to Yanai et al papers. To view these articles, visit https://doi.org/10.1111/apt.17538 and https://doi.org/10.1111/apt.17647