Effect of moxibustion on P2X7R/NF-κB pathway in ulcerative colitis rats with repeated induction of DSS

Abstract

Objective: To investigate the mechanism by which moxibustion regulates the expression of inflammatory cytokines in ulcerative colitis (UC) rats through the P2X7 receptor (P2X7R)/nuclear factor-kappa B (NF-κB) pathway.

Methods: UC was induced using dextran sulfate sodium (DSS) in both wild-type (WT) and P2X7R knockout (KO) mice. General health conditions, pathological changes, and periodic acid-Schiff (PAS) staining of the colonic tissues were analyzed. Immunohistochemistry was used to detect NF-κB p65 protein expression in colonic tissues. Male Sprague-Dawley (SD) rats were randomly assigned to four groups: normal, model, normal + herb-partitioned moxibustion, and model + herb-partitioned moxibustion. UC was induced in rats by cyclic DSS administration. Rats in the herb-partitioned moxibustion group received moxibustion at the bilateral Tianshu (ST25) and Qihai (RN6) acupoints. The effects of herb-partitioned moxibustion were evaluated regarding general health conditions and histopathological alterations in colon tissue. The protein expression of P2X7R and NF-κB p65 in colonic tissues was determined by immunohistochemistry, whereas interleukin (IL)-10 mRNA levels were quantified using real-time quantitative polymerase chain reaction (RT-qPCR). Furthermore, enzyme-linked immunosorbent assay (ELISA) was used to measure serum concentrations of tumor necrosis factor-alpha (TNF-α) and IL-6.

Results: Colonic epithelial damage and inflammatory cell infiltration were significantly reduced in P2X7R KO mice compared to WT mice, along with reduced expression of NF-κB p65 protein in colonic tissues (P < 0.05). Moxibustion improves histopathological damage, goblet cell number, and intestinal mucus secretion in rats with UC. Compared to the normal group, the model group exhibited increased histopathological scores, serum TNF-α, and IL-6 levels, as well as elevated P2X7R and NF-κB p65 protein expression in colonic tissues (P < 0.05). In comparison to the model group, the model + herb-partitioned moxibustion group demonstrated significantly lower histopathological scores, reduced serum TNF-α and IL-6 levels, and decreased P2X7R and NF-κB p65 protein expression (P < 0.05).

Conclusions: Moxibustion at “Tianshu” and “Qihai” acupoints may inhibit the levels of IL-6 and TNF-α inflammatory factors and reduce inflammation in the UC colonic mucosa by regulating the P2X7R/NF-κB p65 pathway in UC colonic tissues.

Keywords

Immunomodulation / Moxibustion / NF-κB p65 / P2X7R / Ulcerative colitis

Conflict of interest statement

The authors declare no conflict of interest.

Funding

This research was funded by the National Natural Science Foundation of China (82174501, 82105012, 82205293, 82205262), Shanghai Municipal Natural Science Foundation (22ZR1458400), Shanghai Talent Development Fund Project (2021058), Shanghai University of Traditional Chinese Medicine Science and Technology Development Project (23KFL111), State Administration of Traditional Chinese Medicine high-level key discipline construction project (zyyzdxk-2023068).

Author contributions

Yanan Liu and Yu Qiao contributed to data curation; Huangan Wu and Luyi Wu contributed to funding acquisition; Yaying Lin, Shiyu Zheng, and Ling Yang contributed to investigation; Yan Huang contributed to resources; Fang Zhang contributed to software; Qin Qi and Jianhua Zhou contributed to supervision; Zhe Ma and Lingjie Li contributed to writing-original draft; Lu Zhu contributed to writing-review & editing. All authors have read and agreed to the published version of the manuscript.

Ethical approval of studies and informed consent

All animal procedures performed in this study were reviewed, approved, and supervised by the Animal Ethics Committee of Shanghai University of Traditional Chinese Medicine, ensuring strict adherence to ethical standards and animal welfare guidelines (Approval number: PZSHUTCM211227012).

Acknowledgments

None.

Data availability

All data generated or analyzed during this study are included in this published article.

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