Methylome and Transcriptome-Based Integration Analysis Identified Molecular Signatures Associated With Meningitis Induced by Glaesserella parasuis

Abstract

Glaesserella parasuis (G. parasuis) can elicit serious inflammatory responses and cause meningitis in piglets. Previous epigenetic studies have indicated that alterations in host DNA methylation may modify the inflammatory response to bacterial infection. However, to date, genome-wide analysis of the DNA methylome during meningitis caused by G. parasuis infection is still lacking. In this study, we employed an unbiased approach using deep sequencing to profile the DNA methylome and transcriptome from G. parasuis infected porcine brain (cerebrum) and integrated the data to identify key differential methylation regions/sites involved in the regulation of the inflammatory response. Results showed that DNA methylation patterns and gene expression profiles from porcine brain were changed after G. parasuis infection. The majority of the altered DNA methylation regions were found in the intergenic regions and introns and not associated with CpG islands, with only a low percentage occurring at promoter or exon regions. Integrated analysis of the DNA methylome and transcriptome identified a number of inversely and positively correlated genes between DNA methylation and gene expression, following the criteria of |log2FC| > 0.5, |diffMethy| > 0.1, and P < 0.05. Differential expression and methylation of two significant genes, semaphoring 4D (SEMA4D) and von Willebrand factor A domain containing 1 (VWA1), were validated by qRT-PCR and bisulfite sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses demonstrated that DNA methylation inversely correlated genes in G. parasuis infected porcine brains were mainly involved with cell adhesion molecules (CAMs), bacterial invasion of epithelial cells, RIG-1-like receptor signaling pathways, and hematopoietic cell lineage signaling pathways. In addition, a protein-protein interaction network of differentially methylated genes found potential candidate molecular interactions relevant to the pathology of G. parasuis infection. To the best of our knowledge, this is the first attempt to integrate the DNA methylome and transcriptome data from G. parasuis infected porcine brains. Our findings will help understanding the contribution of genome-wide DNA methylation to the pathogenesis of meningitis in pigs and developing epigenetic biomarkers and therapeutic targets for the treatment of G. parasuis induced meningitis.

Transcriptome Analysis of miRNA and mRNA in Porcine Skeletal Muscle following Glaesserella parasuis Challenge

“…We confirmed a strong inflammatory response characterized by high expression of inflammatory cytokines in skeletal muscle due to G. parasuis infection. This finding aligns with the well-known predilection sites of G. parasuis infection, such as the lung, arthrosis, pleura, peritoneum, kidney, and meninges [ 42 , 43 , 44 ]. It has been reported that G. parasuis breaks through the lung’s immune defense [ 45 ], allowing it to colonize various parts of the body, including skeletal muscle, through the bloodstream.…”

Integrated Analysis of Long Non-Coding RNA Expression Profiles in Glaesserella parasuis-Induced Meningitis: New Insight into Pathogenesis

“…The G. parasuis SH0165 strain, serotype 5, a high virulent isolate, was isolated from a commercial pig lung with arthritis, fibrinous polyserositis, hemorrhagic pneumonia, and meningitis [1]. The SH0165 strain was grown in tryptic soy broth (TSB) (Difco laboratories, Detroit, MI, USA) or tryptic soy agar (TSA) (Difco laboratories, Detroit, MI, USA) at 37 • C, with 10 µg/mL of nicotinamide adenine dinucleotide (NAD) (Sigma, St.Louis, MO, USA) and 10% fetal bovine serum (FBS) (Gibco, Grand Island, NY, USA).…”

“…Glaesserella parasuis (G. parasuis), a Gram-negative bacterium, colonizes the upper respiratory tract of swine and is the etiological agent of Glässer's disease [1]. The typical characteristic of this disease is fibrinous, meningitis, and polyserositis [2].…”

Quercetin Protects Blood–Brain Barrier Integrity via the PI3K/Akt/Erk Signaling Pathway in a Mouse Model of Meningitis Induced by Glaesserella parasuis

“…Glaesserella parasuis ( G. parasuis , GPS), which causes meningitis, polyserositis, arthritis, and frequently pneumonia-like symptoms, is the etiological agent of Glässer’s disease in pigs [ 1 ]. Meningitis is the most characterized symptom of this disease [ 2 ]. Infection with G. parasuis always results in high morbidity and mortality and leads to significant economic losses for the pig industry [ 3 ].…”