Changes in MicroRNA Expression during Rabbit Hemorrhagic Disease Virus (RHDV) Infection

Abstract

Current knowledge on the role of microRNAs (miRNAs) in rabbit hemorrhagic disease virus (RHDV) infection and the pathogenesis of rabbit hemorrhagic disease (RHD) is still limited. RHDV replicates in the liver, causing hepatic necrosis and liver failure. MiRNAs are a class of short RNA molecules, and their expression profiles vary over the course of diseases, both in the tissue environment and in the bloodstream. This paper evaluates the expression of miRNAs in the liver tissue (ocu-miR-122-5p, ocu-miR-155-5p, and ocu-miR-16b-5p) and serum (ocu-miR-122-5p) of rabbits experimentally infected with RHDV. The expression levels of ocu-miR-122-5p, ocu-miR-155-5p, and ocu-miR-16b-5p in liver tissue were determined using reverse transcription quantitative real-time PCR (RT-qPCR), and the expression level of circulating ocu-miR-122-5p was established using droplet digital PCR (ddPCR). The expression levels of ocu-miR-155-5p and ocu-miR-16b-5p were significantly higher in the infected rabbits compared to the healthy rabbits (a fold-change of 5.8 and 2.5, respectively). The expression of ocu-miR-122-5p was not significantly different in the liver tissue from the infected rabbits compared to the healthy rabbits (p = 0.990), while the absolute expression level of the circulating ocu-miR-122-5p was significantly higher in the infected rabbits than in the healthy rabbits (p < 0.0001). Furthermore, a functional analysis showed that ocu-miR-155-5p, ocu-miR-16b-5p, and ocu-miR-122-5p can regulate the expression of genes involved in processes correlated with acute liver failure (ALF) in rabbits. Search tool for the retrieval of interacting genes/proteins (STRING) analysis showed that the potential target genes of the three selected miRNAs may interact with each other in different pathways. The results indicate the roles of these miRNAs in RHDV infection and over the course of RHD and may reflect hepatic inflammation and impairment/dysfunction in RHD.

Vimentin as a Cap of Invisibility: Proposed Role of Vimentin in Rabbit Hemorrhagic Disease Virus (RHDV) Infection

“…Based on our previous research [ 32 ] of miRNA expression in tissues of rabbits infected with RHDV we firstly hypothesized that expression of vimentin could be correlated with expression of ocu-miR-122-5p, responsible for the regulation of the apoptotic process. In the analysis so far during the RHDV infection, we did not show significant differences in ocu-miR-122-5p expression in liver tissues, impacting VIM expression [ 32 ]. Nevertheless, the downregulation of ocu-miR-122-5p may promote cell proliferation and migration by promoting EMT activity.…”

MicroRNAs participate in the regulation of apoptosis and oxidative stress-related gene expression in rabbits infected with Lagovirus europaeus GI.1 and GI.2 genotypes

“…Our recent studies indicate the role of miRs as micro-players of great importance in viral infections in humans and animals ( Hukowska-Szematowicz et al, 2020 ; Ostrycharz and Hukowska-Szematowicz, 2022 ; Hukowska-Szematowicz et al, 2023 ). miRs can regulate gene expression related to apoptosis ( Su et al, 2015 ) and oxidative stress ( Banerjee et al, 2017 ; Fioravanti et al, 2022 ) during diseases, including viral ones ( Hukowska-Szematowicz et al, 2020 ; Fioravanti et al, 2022 ; Ostrycharz and Hukowska-Szematowicz, 2022 ), and thus affect the activity status of signaling pathways ( Chen, 2015 ; Sadri Nahand et al, 2021 ).…”

“…Further studies showed apoptosis of T and B lymphocytes in the liver, spleen, and granulocytes and lymphocytes in peripheral blood ( Marques et al, 2010 ; Niedzwiedzka-Rystwej and Deptula, 2012 ; Hukowska-Szematowicz, 2013 ; Niedzwiedzka-Rystwej et al, 2013a , b ). Hukowska-Szematowicz et al (2020) showed that after infection of rabbits with the L. europaeus GI.1 genotype, the expression of proapoptotic miR-16-5p increased in the liver. The same studies did not show changes in the liver’s expression of miR-122-5p (potentially involved in oxidative stress) but were detected in the serum.…”

“…The above findings indicate that apoptosis and oxidative stress play an essential role in the pathogenesis of RHD. However, so far [apart from the research of Hukowska-Szematowicz et al (2020) and Ostrycharz and Hukowska-Szematowicz (2022) ], nothing is known about the molecular signatures of regulatory interactions between miRs and apoptosis and oxidative stress in L. europaeus infection/pathogenesis of RHD.…”

“…Therefore, we undertook research aimed at assessing the expression of miRs and their target genes related to apoptosis and oxidative stress and assessing their potential impact on the pathways in infection with L. europaeus —two genotypes (GI.1 and GI.2) with different virulence in four tissues (liver, lungs, kidneys, and spleen). Based on in silico analysis and our previous literature data ( Hukowska-Szematowicz et al, 2020 ; Ostrycharz and Hukowska-Szematowicz, 2022 ), we selected miRs/target genes in the apoptosis and oxidative stress processes. For apoptosis: miR-21 (target genes—phosphatase and tensin homolog [ PTEN ] and programmed cell death factor 4 [ PDCD4 ]), miR-16b (antiapoptotic B cell lymphoma 2 [ Bcl-2 ] and C-X-C motif chemokine ligand 10 [ CXCL10 ]), miR-34a (p53 protein gene ( p53 ), and silent information regulator 1 [ SIRT1 ]).…”