Serum Microcystin-LR Levels Linked with Risk of Inflammatory Bowel Disease: A Matched Case-Control Study in China

Xuejie Chen; Wenya Liu; Yangjie Liao; Xin Xiang; Yue Yang; Li Tian; Xiang Gao; Qian Cao; Hong Guo; Kang Chao; Fengmei Song; Rongbei Liu; Ying Li; Shuyu Ye; Jiangang Wang; Fei Yang; Xiaoyan Wang

doi:10.1021/envhealth.3c00212

Serum Microcystin-LR Levels Linked with Risk of Inflammatory Bowel Disease: A Matched Case-Control Study in China

Environ Health (Wash). 2024 May 3;2(7):453-464. doi: 10.1021/envhealth.3c00212. eCollection 2024 Jul 19.

Authors

Xuejie Chen¹, Wenya Liu^{2

3}, Yangjie Liao¹, Xin Xiang¹, Yue Yang², Li Tian¹, Xiang Gao⁴, Qian Cao⁵, Hong Guo⁶, Kang Chao⁴, Fengmei Song², Rongbei Liu⁵, Ying Li⁷, Shuyu Ye¹, Jiangang Wang⁷, Fei Yang^{2

3}, Xiaoyan Wang¹

Affiliations

¹ Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha, 410013, China.
² Hunan Province Key Laboratory of Typical Environmental Pollution and Health Hazards, School of Public Health, Hengyang Medical School, University of South China, Hengyang, 421001, China.
³ Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha, 410078, China.
⁴ Department of Gastroenterology, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510510, China.
⁵ Department of Gastroenterology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, 310018, China.
⁶ Department of Gastroenterology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 401121, China.
⁷ Health Management Center, Third Xiangya Hospital, Central South University, Changsha, 410013, China.

Abstract

Microcystin-LR (MC-LR), the most prevalent and diverse cyanotoxin produced by harmful cyanobacterial blooms, has been linked to gastrointestinal toxicity. Therefore, we conducted a case-control study across four regions in China to investigate this relationship. Inflammatory bowel disease (IBD) cases (219) were matched with healthy controls (438) based on age and gender and conditional logistic regression models and Restricted cubic splines were used to evaluate the association between MC-LR exposure and IBD risk. We used quantitative real-time polymerase chain reaction to measure the expression levels of inflammatory factors. The levels of protein expression in the colorectum were determined using Western blotting (WB). Compared to the lowest quartile of serum MC-LR levels, the adjusted odds ratios and 95% confidence intervals (CI) for the highest quartiles of serum MC-LR levels were 5.51 (2.70, 11.21). The RCS was shown the association between serum MC-LR levels and IBD risk was nonlinear (P _nonlinear < 0.001). In the animal experiments, MC-LR resulted in colorectal injury via the PI3K/AKT signaling pathway. Our study provides the evidence that serum MC-LR exposure is significantly associated with the risk of IBD in China. Animal study results indicate that MC-LR probably causes IBD via the PI3K/AKT signaling pathway.