AUTHOR=Li Ya-Ting , Ye Jian-Zhong , Lv Long-Xian , Xu Hong , Yang Li-Ya , Jiang Xian-Wan , Wu Wen-Rui , Shi Ding , Fang Dai-Qiong , Bian Xiao-Yuan , Wang Kai-Cen , Wang Qiang-Qiang , Xie Jiao-Jiao , Lu Yan-Meng , Li Lan-Juan 

TITLE=Pretreatment With Bacillus cereus Preserves Against D-Galactosamine-Induced Liver Injury in a Rat Model

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.01751

DOI=10.3389/fmicb.2019.01751

ISSN=1664-302X

ABSTRACT=<p><italic>Bacillus cereus</italic> (<italic>B. cereus</italic>) functions as a probiotic in animals, but the underlying mechanisms remain unclear. We aim to evaluate the protective effects and definite mechanism by which orally administered <italic>B. cereus</italic> prevents D-galactosamine (D-GalN)-induced liver injury in rats. Twenty-one Sprague–Dawley rats were equally assigned into three groups (<italic>N</italic> = 7 animals per group). <italic>B. cereus</italic> ATCC11778 (2 × 10<sup>9</sup> colony-forming units/ml) was administered to the <italic>B. cereus</italic> group via gavage, and phosphate-buffered saline was administered to the positive control (PC) and negative control (NC) groups for 2 weeks. The PC and <italic>B. cereus</italic> groups received 1.1 g/kg D-GalN via an intraperitoneal injection to induce liver injury. The blood, terminal ileum, liver, kidney and mesenteric lymph nodes (MLNs) were collected for histological examinations and to evaluate bacterial translocation. Liver function was also determined. Fecal samples were collected for deep sequencing of the 16S rRNA on an Illumina MiSeq platform. <italic>B. cereus</italic> significantly attenuated D-GalN-induced liver injury and improved serum alanine aminotransferase (ALT) and serum cholinesterase levels (<italic>P</italic> &lt; 0.05 and <italic>P</italic> &lt; 0.01, respectively). <italic>B. cereus</italic> modulated cytokine secretion, as indicated by the elevated levels of the anti-inflammatory cytokine interleukin-10 (IL-10) in both the liver and plasma (<italic>P</italic> &lt; 0.05 and <italic>P</italic> &lt; 0.01, respectively) and the substantially decreased levels of the cytokine IL-13 in the liver (<italic>P</italic> &lt; 0.05). Pretreatment with <italic>B. cereus</italic> attenuated anoxygenic bacterial translocation in the veins (<italic>P</italic> &lt; 0.05) and liver (<italic>P</italic> &lt; 0.05) and upregulated the expression of the tight junction protein 1. The gut microbiota from the <italic>B. cereus</italic> group clustered separately from that of the PC group, with an increase in species of the <italic>Ruminococcaceae</italic> and <italic>Peptococcaceae</italic> families and a decrease in those of the <italic>Parabacteroides</italic>, <italic>Paraprevotella</italic>, and <italic>Desulfovibrio</italic> families. The potential probiotic <italic>B. cereus</italic> attenuated liver injury by restoring the gut flora balance and enhancing the intestinal barrier function.</p>