Induction of protection against foot-and-mouth disease virus in cell culture and transgenic suckling mice by miRNA targeting integrin αv receptor

Hepatic Sinusoid Capillarizate via IGTAV/FAK Pathway Under High Glucose

The incidence of diabetic patients with non-alcoholic fatty liver disease (NAFLD) is continuously increasing worldwide. However, the specific mechanisms of NAFLD patients with diabetes are still not clear. Recent studies have indicated that integrins play an important role in NAFLD. In this study, we considered the relationship between integrin αv (IGTAV)/FAK pathway and sinusoidal capillarization. We investigated the difference between the expression of IGTAV, laminin (LN), focal adhesion kinase (FAK), and phosphor-FAK protein in human liver sinusoidal endothelial cells (HLSECs) to explore the specific mechanisms of the diseases of NAFLD with diabetes under high glucose. We cultured and identified the HLSECs and constructed the recombinant lentivirus vector with IGTAV shRNA by quantitative real-time PCR (qRT-PCR) to silence the IGTAV gene. Cells were divided into groups of 25 mmol/L glucose and 25 mmol/L mannitol. We measured the protein levels of IGTAV, LN, FAK, and phosphor-FAK by western blot at 2 h, 6 h, and 12 h before and after IGTAV gene silencing. The lentivirus vector was successfully constructed with IGTAV shRNA. The HLSECs under high glucose were observed by scanning electron microscope. SPSS19.0 was used for statistical analysis. High glucose significantly increased the expression of IGTAV, LN, and phosphor-FAK protein in HLSECs; the shRNA IGTAV could effectively inhibit the expression of phosphor-FAK and LN at 2 h and 6 h. Inhibition of the phosphor-FAK could effectively decrease the expression of LN in HLSECs at 2 h and 6 h under high glucose. Inhibition of IGTAV gene of HLSECs under high glucose could improve hepatic sinus capillarization. Inhibition of IGTAV and phosphor-FAK decreased the expression of LN. High glucose led to hepatic sinus capillarization via IGTAV/ FAK pathway.

Preliminary study on molecular mechanism of COVID-19 intervention by Polygonum cuspidatum through computer bioinformatics

To explore the mechanism of action of Polygonum cuspidatum in intervening in coronavirus disease 2019 using a network pharmacology approach and to preliminarily elucidate its mechanism. The active ingredients and action targets of P cuspidatum were classified and summarized using computer virtual technology and molecular informatics methods. The active ingredients and relevant target information of P cuspidatum were identified using the TCM Systematic Pharmacology Database and Analysis Platform, the TCM Integrated Pharmacology Research Platform v2.0, and the SwissTarget database. The GENECARDS database was used to search for COVID-19 targets. The STRING database was analyzed and combined with Cytoscape 3.7.1 software to construct a protein interaction network map to screen the core targets. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis was then performed. The core compound, polydatin, was selected and the core targets were analyzed by computer virtual docking using software such as discovery studio autodock tool. In vitro cell models were constructed to experimentally validate the activity of the core compound, polydatin. By computer screening, we identified 9 active ingredients and their corresponding 286 targets from P cuspidatum. A search of the GENECARDS database for COVID-19 yielded 303 core targets. By mapping the active ingredient targets to the disease targets, 27 overlapping targets could be extracted as potential targets for the treatment of COVID-19 with P cuspidatum. In addition, the enrichment analysis of Kyoto Encyclopedia of Genes and Genomes pathway on core targets showed that the coronavirus disease, MAPK signaling pathway, NF kappa B signaling pathway, and other signaling pathways were highly enriched. Combined with the degree-high target analysis in the protein interaction network, it was found to be mainly concentrated in the NF-kappaB (NF-κB) signaling pathway, indicating that the NF-κB signaling pathway may be an important pathway for P cuspidatum intervention. In vitro assays showed no effect of 0.1 to 10 μM polydatin on cell viability, but an inhibitory effect on the transcriptional activity of NF-κB-RE. Molecular docking showed stable covalent bonding of polydatin molecules with Il-1β protein at residue leu-26, TNF protein ser-60, residue gly-121, and residue ile-258 of ICAM-1 protein, indicating a stable docking result. The treatment of COVID-19 with P cuspidatum is characterized by multi-component, multi-target, and multi-pathway, which can exert a complex network of regulatory effects through the interaction between different targets, providing a new idea and basis for further exploration of the mechanism of action of P cuspidatum in the treatment of COVID-19.

Computational insights into RNAi-based therapeutics for foot and mouth disease of Bos taurus

Foot-and-mouth disease (FMD) endangers a large number of livestock populations across the globe being a highly contagious viral infection in wild and domestic cloven-hoofed animals. It adversely affects the socioeconomic status of millions of households. Vaccination has been used to protect animals against FMD virus (FMDV) to some extent but the effectiveness of available vaccines has been decreased due to high genetic variability in the FMDV genome. Another key aspect that the current vaccines are not favored is they do not provide the ability to differentiate between infected and vaccinated animals. Thus, RNA interference (RNAi) being a potential strategy to control virus replication, has opened up a new avenue for controlling the viral transmission. Hence, an attempt has been made here to establish the role of RNAi in therapeutic developments for FMD by computationally identifying (i) microRNA (miRNA) targets in FMDV using target prediction algorithms, (ii) targetable genomic regions in FMDV based on their dissimilarity with the host genome and, (iii) plausible anti-FMDV miRNA-like simulated nucleotide sequences (SNSs). The results revealed 12 mature host miRNAs that have 284 targets in 98 distinct FMDV genomic sequences. Wet-lab validation for anti-FMDV properties of 8 host miRNAs was carried out and all were observed to confer variable magnitude of antiviral effect. In addition, 14 miRBase miRNAs were found with better target accessibility in FMDV than that of Bostaurus. Further, 8 putative targetable regions having sense strand properties of siRNAs were identified on FMDV genes that are highly dissimilar with the host genome. A total of 16 SNSs having > 90% identity with mature miRNAs were also identified that have targets in FMDV genes. The information generated from this study is populated at http://bioinformatics.iasri.res.in/fmdisc/ to cater the needs of biologists, veterinarians and animal scientists working on FMD.

Downregulation of miR-146a inhibits influenza A virus replication by enhancing the type I interferon response in vitro and in vivo

Albeit microRNAs (miRNAs) have become increasingly appreciated for their essential roles in innate immune responses to viral infections; however, it is unknown how host miRNAs regulate influenza A virus (IAV)-induced inflammation. The aim of our study was to investigate the role of miR-146a in IAV replication in vitro and in vivo. In vitro, we found miR-146a was significantly upregulated in A549 cells with IAV infection. Overexpression of miR-146a promoted IAV replication, while downregulation of miR-146a repressed replication. We found that miR-146a diminished type I interferon (IFN) responses by decreasing IFN-β production and IFN-stimulated gene (ISG) expression. Furthermore, we found the IFNs level and IAV replication regulated by miR-146a inhibitor was partially reversed by depletion of interferon receptor (IFNAR) 1 or 2. In addition, we found that miR-146a directly targets tumor necrosis factor receptor association factor 6 (TRAF6), which is involved in the production of type I IFN, and TRAF6 overexpression reversed the replication-promoting effect of miR-146a on IAV. In vivo, inhibition of miR-146a alleviated IAV-induced mice lung injury and promoted survival rates by promoting type I antiviral activities. It is, therefore, concluded that downregulation of miR-146a inhibits IAV replication by enhancing type I IFN response through its target gene TRAF6 in vitro and in vivo, suggesting miR-146a antagomir might be a potential therapeutic target during IAV infection.

Advances in the Application and Impact of MicroRNAs as Therapies for Skin Disease

The advent of RNA interference (RNAi) technology has profoundly impacted molecular biology research and medicine but has also advanced the field of skin care. Both effector molecules of RNAi, short-interfering RNA molecules and microRNAs (miRNAs), have been explored for their relative impact and utility for treating a variety of skin conditions. These post-transcriptional RNA regulatory molecules down-modulate protein expression through targeting of the 3' untranslated regions of messenger RNAs, leading to their degradation or repression through sequestration. As researchers hunt for genetic linkages to skin diseases, miRNA regulators have emerged as key players in the biology of keratinocytes, fibroblasts, melanocytes, and other cells of the skin. Herein, we attempt to coalesce the current efforts to combat various skin disorders and diseases through the development of miRNA-based technologies.

miR-127-5p negatively regulates enterovirus 71 replication by directly targeting SCARB2

Enterovirus 71 (EV71) is the major causative agent of hand‐foot‐and‐mouth disease in young children and can cause severe cerebral and pulmonary complications and even fatality. This study aimed at elucidating whether and how EV71 infection is regulated by a cellular microRNA, miR‐127‐5p. We found that miR‐127‐5p can downregulate the expression of SCARB2, a main receptor of EV71, by targeting two potential sites in its 3′ UTR region and inhibit EV71 infection. Meanwhile, miR‐127‐5p expression was upregulated during EV71 infection. Notably, transfecting cells with miR‐127‐5p mimics led to a significant decrease in viral replication, while inhibition of endogenous miR‐127‐5p facilitated viral replication. Furthermore, our evidence showed that miR‐127‐5p did not affect postentry viral replication. Taken together, these results indicated that miR‐127‐5p inhibited EV71 replication by targeting the SCARB2 mRNA.

RNA interference-based technology: what role in animal agriculture?

Animal agriculture faces a broad array of challenges, ranging from disease threats to adverse environmental conditions, while attempting to increase productivity using fewer resources. RNA interference (RNAi) is a biological phenomenon with the potential to provide novel solutions to some of these challenges. Discovered just 20 years ago, the mechanisms underlying RNAi are now well described in plants and animals. Intracellular double-stranded RNA triggers a conserved response that leads to cleavage and degradation of complementary mRNA strands, thereby preventing production of the corresponding protein product. RNAi can be naturally induced by expression of endogenous microRNA, which are critical in the regulation of protein synthesis, providing a mechanism for rapid adaptation of physiological function. This endogenous pathway can be co-opted for targeted RNAi either through delivery of exogenous small interfering RNA (siRNA) into target cells or by transgenic expression of short hairpin RNA (shRNA). Potentially valuable RNAi targets for livestock include endogenous genes such as developmental regulators, transcripts involved in adaptations to new physiological states, immune response mediators, and also exogenous genes such as those encoded by viruses. RNAi approaches have shown promise in cell culture and rodent models as well as some livestock studies, but technical and market barriers still need to be addressed before commercial applications of RNAi in animal agriculture can be realised. Key challenges for exogenous delivery of siRNA include appropriate formulation for physical delivery, internal transport and eventual cellular uptake of the siRNA; additionally, rigorous safety and residue studies in target species will be necessary for siRNA delivery nanoparticles currently under evaluation. However, genomic incorporation of shRNA can overcome these issues, but optimal promoters to drive shRNA expression are needed, and genetic engineering may attract more resistance from consumers than the use of exogenous siRNA. Despite these hurdles, the convergence of greater understanding of RNAi mechanisms, detailed descriptions of regulatory processes in animal development and disease, and breakthroughs in synthetic chemistry and genome engineering has created exciting possibilities for using RNAi to enhance the sustainability of animal agriculture.

Development of sheep kidney cells with increased resistance to different subgenotypes of BVDV-1 by RNA interference

Bovine viral diarrhea virus (BVDV) should be a ubiquitous viral pathogen to the cattle and sheep industry. This pathogen is responsible for severe economic losses. We previously showed that plasmid-mediated dual short hairpin RNA (shRNA) efficiently inhibit BVDV replication in bovine kidney epithelial (MDBK) cells. In this study, we delivered the dual shRNA system to sheep fibroblasts and generated transgenic cell colonies. These transgenic fibroblasts were further used for somatic cell nuclear transfer (SCNT). Three lambs were born at full term, but perished soon after birth. Integration of shRNA into the genome of cloned sheep was confirmed by PCR and expression of shRNA in transgenic sheep was confirmed by real-time PCR. Kidney epithelial cells were isolated from transgenic sheep and challenged with multiple BVDV subgenotypes (BVDV-1a, BVDV-1b and BVDV-1c). The dual shRNA expressed in transgenic kidney epithelial cells significantly inhibited BVDV replication in a cross-resistance manner. Our results showed that transgenic RNAi might be a useful tool for preparation of transgenic animals with increased resistance to BVDV.