Carbon Black Nanoparticles Exposure Induces Intestinal Flora Dysbiosis and Consequent Activation of Gut-Liver Axis Leading to Liver Lipid Accumulation in Zebrafish

Background: Carbon black nanoparticles (CBNPs) are a major carbonaceous nanomaterial, which have been widely left in the environment. The integrity of the gut-liver axis function is critical to the survival of animals. Therefore, we studied the effects of three concentrations of CBNPs (50, 100, 200 mg/L) on zebrafish intestines, liver and intestinal flora. Results: : The results showed that CBNPs exposure could reduce the diversity of intestinal flora, change the structure of core microbial populations, enhance the permeability of the intestinal mucosal barrier, and cause changes in genes related to tight junctions in intestinal tissues. The H&E staining and Oil red O staining showed that CBNPs exposure would lead to vacuolar degeneration and lipid accumulation in zebrafish liver. Further detection of glycolipid metabolism related genes showed that CBNPs exposure induced the up-regulation of glycolysis related genes PFKFB3, LDHA, and LEPr, reduces the expression of glycogen synthase kinase GSK-3b, and increases lipid transport and production related genes PPAR-α, PPAR-γ, LIPC, apoa4, Fabp2 and Fabp11 expression. Conclusions: : In brief, our data demonstrated that CBNPs exposure induced intestinal microflora disturbance in zebrafish can lead to liver lipid accumulation.