Intest Res.  2023 Jul;21(3):306-317. 10.5217/ir.2022.00118.

Does caffeine have a double-edged sword role in inflammation and carcinogenesis in the colon?

• Mizoguchi E
• Sadanaga T
• Okada T
• Minagawa T
• Akiba J

• KMID: 2544754
• DOI: http://doi.org/10.5217/ir.2022.00118

Abstract

Caffeine (1,3,7-trimethylxanthine, also abbreviated to CAF) is a natural chemical with stimulant effects and is commonly included in many drinks and foods, including coffee, tea, cola, energy drinks, cocoa, chocolates, and so on. Our group previously reported that oral administration of CAF efficiently suppressed the development of intestinal inflammation in a dextran sulfate sodium (DSS)-induced murine acute colitis model by suppressing the expression of chitinase 3-like 1, one of the mammalian chitinases without enzymatic activity. Chitinases are hydrolytic enzymes that break down chitin, a polymer of N-acetylglucosamine, and chitinase-like proteins have no enzymatic activity with preserving chitin-binding ability. CAF binds a cleft of the chitinase active site and plays a role as a pan-chitinase inhibitor. Although CAF showed an anti-inflammatory effect in the above model, oral administration of low-dose CAF with 10% sucrose showed potentially neoplastic effects in colonic epithelial cells in a DSS-induced murine chronic colitis model. In this review, we would like to discuss the pros and cons of coffee/CAF in colonic inflammation and neoplasia with an example of pathological finding.

Keyword

Inflammatory bowel disease; Colitis-associated neoplasms; Sucrose; Caffeine; Chitinase 3-like 1

Figure

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  Fig. 1. Risk may be altered depending on the intake of high amounts of caffeine (CAF). Diseases for which CAF is associated with decreased risk (advantages) include non-insulin-dependent diabetes mellitus (NIDDM), Parkinson’s disease, Alzheimer’s disease, colorectal cancer, and inflammatory bowel disease (IBD), as well as renal and hepatic disorders. In contrast, diseases for which CAF increases the risk (disadvantages) include insomnia due to CAF’s stimulant effects, headaches, and many other effects. CAF also influences the risk of maintaining pregnancy as well as increasing DNA-damaged sperm.

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  Fig. 2. Representative histological images of low-dose caffeine (CAF) with sucrose-treated mice. Low-grade dysplasia (A), high-grade dysplasia (B), carcinoma in situ (C), and invasive cancer (D) in the CAF with 10% sucrose-treated mice were shown (all hematoxylin and eosin stain, ×10).

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