Analysis of the microRNA expression profiles of chicken dendritic cells in response to H9N2 avian influenza virus infection

Role of miRNA in Highly Pathogenic H5 Avian Influenza Virus Infection: An Emphasis on Cellular and Chicken Models

The avian influenza virus, particularly the H5N1 strain, poses a significant and ongoing threat to both human and animal health. Recent outbreaks have affected domestic and wild birds on a massive scale, raising concerns about the virus' spread to mammals. This review focuses on the critical role of microRNAs (miRNAs) in modulating pro-inflammatory signaling pathways during the pathogenesis of influenza A virus (IAV), with an emphasis on highly pathogenic avian influenza (HPAI) H5 viral infections. Current research indicates that miRNAs play a significant role in HPAI H5 infections, influencing various aspects of the disease process. This review aims to synthesize recent findings on the impact of different miRNAs on immune function, viral cytopathogenicity, and respiratory viral replication. Understanding these mechanisms is essential for developing new therapeutic strategies to combat avian influenza and mitigate its effects on both human and animal populations.

miRNA Expression Signatures Induced by Chicken Astrovirus Infection in Chickens

miRNAs represent ubiquitous regulators of gene expression and play an important and pivotal regulatory role in viral disease pathogenesis and virus-host interactions. Although previous studies have provided basic data for understanding the role of miRNAs in the molecular mechanisms of viral infection in birds, the role of miRNAs in the regulation of host responses to chicken astrovirus (CAstV) infection in chickens is not yet understood. In our study, we applied next-generation sequencing to profile miRNA expression in CAstV-infected chickens and to decipher miRNA-targeted specific signaling pathways engaged in potentially vital virus-infection biological processes. Among the 1354 detected miRNAs, we identified 58 mature miRNAs that were significantly differentially expressed in infected birds. Target prediction resulted in 4741 target genes. GO and KEGG pathway enrichment analyses showed that the target genes were mainly involved in the regulation of cellular processes and immune responses.

Regulation of mRNA and miRNA in the response to Salmonella enterica serovar Enteritidis infection in chicken cecum

BACKGROUND

Salmonella enterica, serovar Enteritidis (SE) is a food-borne pathogen, which can cause great threat to human health through consumption of the contaminated poultry products. Chicken is the main host of SE. The mRNA and microRNA (miRNA) expression profiles were analyzed on cecum of Shouguang chicken via next-generation sequencing and bioinformatics approaches. The treated group was inoculated SE, and the control group was inoculated with phosphate buffer saline (PBS).

RESULTS

There were 1760 differentially expressed mRNAs in the SE-infected group, of which 1046 were up-regulated mRNA, and 714 were down-regulated mRNA. In addition, a total of 821 miRNAs were identified, and 174 miRNAs were differentially expressed, of which 100 were up-regulated and 74 were down-regulated. Functional enrichment of differentially expressed mRNAs was similar to miRNA target genes. The functional analysis results of differentially expressed mRNAs and miRNAs were performed. Immune-related processes and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways were enriched by up-regulated mRNA. The down-regulated mRNAs were enriched in tissue development and metabolic-related KEGG pathways. The functional analysis of up-regulated miRNA target genes was similar to the down-regulated mRNAs. The down-regulated miRNA target genes were enriched in metabolic-related GO (Gene Ontology) -BP (Biological process) terms and KEGG pathways. The overlap of the up-regulated mRNA and the up-regulated miRNA target genes (class I) was 325, and the overlap of the down-regulated miRNA target genes (class II) was 169. The class I enriched in the immune-related GO-BP terms and KEGG pathways. The class II mainly enriched in metabolic-related GO-BP terms and KEGG pathways. Then we detected the expression of mRNA and miRNA through qRT-PCR. The results shown that the expression of HHIP, PGM1, HTR2B, ITGB5, RELN, SFRP1, TCF7L2, SCNN1A, NEK7, miR-20b-5p, miR-1662, miR-15a, miR-16-1-3p was significantly different between two groups. Dual-luciferase reporter assay was used to detect the relationship between miR-20b-5p and SCNN1A. The result indicated that miR-20b-5p regulate immune or metabolic responses after SE infection in Shouguang chickens by directly targeting SCNN1A.

CONCLUSIONS

The findings here contribute to the further analysis of the mechanism of mRNA and miRNA defense against SE infection, and provide a theoretical foundation for the molecular disease-resistant breeding of chickens.

Stress-induced immunosuppression affecting avian influenza virus vaccine immune response through miR-20a-5p/NR4A3 pathway in chicken

Stress-induced immunosuppression is one of the most common hazards in poultry intensive production, which often leads to vaccination failure and severe economic losses. At present, there is no report about the function and mechanism of circulating miRNA on stress-induced immunosuppression affecting immune response. In this study, the changes of circulating miR-20a-5p under stress-induced immunosuppressive condition were analyzed by qRT-PCR, and the key time points, tissues and mechanisms for functional regulation of miR-20a-5p in the process of stress-induced immunosuppression affecting avian influenza virus (AIV) vaccine immune response were identified. The results showed that stress-induced immunosuppression down-regulated miR-20a-5p and further affected AIV vaccine immune response, in which 5 day post immunization (dpi) was a key time point, and the heart, lung, and proventriculus were the important tissues. The game relationship analysis between miR-20a-5p and its target nuclear receptor subfamily 4 group A member 3 (NR4A3) gene showed that "miR-20a-5p/NR4A3" pathway was the potential key mechanism of this process, especially for heart and lung. This study provides insights into the molecular mechanisms of stress-induced immunosuppression affecting immune response.

Lnc90386 Sponges miR-33-5p to Mediate Mycoplasma gallisepticum-Induced Inflammation and Apoptosis in Chickens via the JNK Pathway

Mycoplasma gallisepticum (MG) is one of the most important pathogens, that causes chronic respiratory disease (CRD) in chickens. Long non-coding RNAs (lncRNAs) are emerging as new regulators for many diseases and some lncRNAs can function as competing endogenous RNAs (ceRNAs) to regulate mRNAs by competitively binding to miRNAs. Here, we found that miR-33-5p was significantly up-regulated both in MG-infected chicken embryonic lungs and chicken embryo fibroblast cells (DF-1), and Lnc90386 negatively correlated with miR-33-5p. miR-33-5p, as a new regulator for MG infection, repressed apoptosis, inflammatory factors in DF-1 cells by targeting JNK1. Further analyses showed that Lnc90386 sponged miR-33-5p to weaken its inhibitory effect on JNK1, forming the ceRNA regulatory network. Furthermore, knockdown of Lnc90386 significantly inhibited apoptosis and inflammatory factors, and promoted DF-1 cells proliferation. However, co-treatment with miR-33-5p inhibitor and Lnc90386 siRNA showed that knockdown of Lnc90386 could partially eliminate the inhibiting effect of miR-33-5p inhibitor on inflammation, cell apoptosis and proliferation. In conclusion, Lnc90386 sponges miR-33-5p to defend against MG infection by inhibiting the JNK signaling pathway.

The Notch Pathway: A Link Between COVID-19 Pathophysiology and Its Cardiovascular Complications

COVID-19 is associated with a large number of cardiovascular sequelae, including dysrhythmias, myocardial injury, myocarditis and thrombosis. The Notch pathway is one likely culprit leading to these complications due to its direct role in viral entry, inflammation and coagulation processes, all shown to be key parts of COVID-19 pathogenesis. This review highlights links between the pathophysiology of SARS-CoV2 and the Notch signaling pathway that serve as primary drivers of the cardiovascular complications seen in COVID-19 patients.