Comparative Analysis of Differentially Expressed Genes in Chondrocytes from Rats Exposed to Low Selenium and T-2 Toxin.

The aim of this study was to construct rat models of environmental risk factors for Kashin-Beck disease (KBD) with low selenium and T-2 toxin levels and to screen the differentially expressed genes (DEGs) between the rat models exposed to environmental risk factors. The Se-deficient (SD) group and T-2 toxin exposure (T-2) group were constructed. Knee joint samples were stained with hematoxylin-eosin, and cartilage tissue damage was observed. Illumina high-throughput sequencing technology was used to detect the gene expression profiles of the rat models in each group. Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analysis were performed and five differential gene expression results were verified by quantitative real-time polymerase chain reaction (qRT‒PCR). A total of 124 DEGs were identified from the SD group, including 56 upregulated genes and 68 downregulated genes. A total of 135 DEGs were identified in the T-2 group, including 68 upregulated genes and 67 downregulated genes. The DEGs were significantly enriched in 4 KEGG pathways in the SD group and 9 KEGG pathways in the T-2 group. The expression levels of Dbp, Pc, Selenow, Rpl30, and Mt2A were consistent with the results of transcriptome sequencing by qRT‒PCR. The results of this study confirmed that there were some differences in DEGs between the SD group and the T-2 group and provided new evidence for further exploration of the etiology and pathogenesis of KBD.

Comparative Analysis of Gut Microbiota from Rats Induced by Se Deficiency and T-2 Toxin.

The aim of this study was to analyze the differences in gut microbiota between selenium deficiency and T-2 toxin intervention rats. Knee joint and fecal samples of rats were collected. The pathological characteristics of knee cartilage were observed by safranin O/fast green staining. DNA was extracted from fecal samples for PCR amplification, and 16S rDNA sequencing was performed to compare the gut microbiota of rats. At the phylum level, Firmicutes (81.39% vs. 77.06%) and Bacteroidetes (11.11% vs. 14.85%) were dominant in the Se-deficient (SD) group and T-2 exposure (T-2) groups. At the genus level, the relative abundance of Ruminococcus_1 (12.62%) and Ruminococcaceae_UCG-005 (10.31%) in the SD group were higher. In the T-2 group, the relative abundance of Lactobacillus (11.71%) and Ruminococcaceae_UCG-005 (9.26%) were higher. At the species level, the high-quality bacteria in the SD group was Ruminococcus_1_unclassified, and Ruminococcaceae_UCG-005_unclassified in the T-2 group. Lactobacillus_sp__L_YJ and Lactobacillus_crispatus were the most significant biomarkers in the T-2 group. This study analyzed the different compositions of gut microbiota in rats induced by selenium deficiency and T-2 toxin, and revealed the changes in gut microbiota, so as to provide a certain basis for promoting the study of the pathogenesis of Kashin-Beck disease (KBD).