Effects of Chronic Exposure to Microcystin-LR on the Gut Microbiota of Male Mice

Abstract

Increasing evidence indicates that environmental pollutants can change human gut microbiota. Microcystin–leucine arginine (MC-LR), considered a major hazard to mammals, is one of the important contaminants. However, little is known about the long-term influence of MC-LR on gut microbial communities. We aimed to investigate the effect of MC-LR on gut microbiota composition and functions by conducting a chronic exposure of male mice to MC-LR via the oral route. Using 16S rRNA gene sequencing analysis on cecum samples of mice, our results showed that significant changes of species diversity were observed in the gut microbiota of MC-LR-exposed mice. In addition, comparative analysis of the microbial communities showed that the reduction of the Actinobacteria and Saccharibacteria populations was detected in MC-LR-exposed mice. Collectively, our study highlighted the significant effects of MC-LR on the shift of gut microbial communities which could contribute to the development of metabolic syndromes.

Integration of metagenomic and metabolomic insights into the effects of microcystin-LR on intestinal microbiota of Litopenaeus vannamei

“…Ten and forty microgram per liter MC-LR can induce a decrease in intestinal microbiota diversity and a change in community composition of Procambarus clarkii (Zhang et al, 2020b). Similar phenomena have been observed in mice (Chen et al, 2015;Zhang et al, 2016Zhang et al, , 2020aZhuang et al, 2021) and zebrafish (Li et al, 2019a). Additionally, MC-LR stress can also alter the functional gene profiles of intestinal microbiota in rats, including chitin, starch and limonene metabolism (Lin et al, 2015).…”

Exposure to Microcystin-LR Promotes Colorectal Cancer Progression by Altering Gut Microbiota and Associated Metabolites in APCmin/+ Mice

“…One study found that mice exposed to MC-LR exhibited a significant increase in Turicibacter and Clostridium levels while showing a substantial decrease in Ruminococcus and Alloprevotella levels [36]. Another study showed that a decrease in Actinobacteria and Saccharibacteria levels was observed in mice exposed to MC-LR [55]. However, most studies have used normal rather than cancer-prone mice.…”

Subchronic Microcystin-LR Aggravates Colorectal Inflammatory Response and Barrier Disruption via Raf/ERK Signaling Pathway in Obese Mice

“…An in vitro study revealed that MCs can affect intestinal barrier function by decreasing the expression of cytoskeletal proteins closely linked to Occludin and ZO-1 in IECs and by dose-dependently impairing the integrity of the intestinal barrier [37]. Zhuang et al also discovered that chronic MC-LR contamination of drinking water in mice for 6 months decreased the expression of mRNA for intestinal tight junction Claudin, Occludion, and ZO-1 [38]. The mRNA levels of intestinal epithelial tight junction-related genes (Claudin-5, Occludin, and ZO-1) were significantly reduced in zebrafish reared for 21 days with MC-LR (35 µg/L) [39].…”