SARS-CoV-2 N Protein Induces Acute Kidney Injury via Smad3-Dependent G1 Cell Cycle Arrest Mechanism.

COVID-19 is infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and can cause severe multiple organ injury and death. Kidney is one of major target organs of COVID-19 and acute kidney injury (AKI) is common in critically ill COVID-19 patients. However, mechanisms through which COVID-19 causes AKI remain largely unknown and treatment remains unspecific and ineffective. Here, the authors report that normal kidney-specifically overexpressing SARS-CoV-2 N develops AKI, which worsens in mice under ischemic condition. Mechanistically, it is uncovered that SARS-CoV-2 N-induced AKI is Smad3-dependent as SARS-CoV-2 N protein can interact with Smad3 and enhance TGF-ß/Smad3 signaling to cause tubular epithelial cell death and AKI via the G1 cell cycle arrest mechanism. This is further confirmed in Smad3 knockout mice and cells in which deletion of Smad3 protects against SARS-CoV-2 N protein-induced cell death and AKI in vivo and in vitro. Most significantly, it is also found that targeting Smad3 with a Smad3 pharmacological inhibitor is able to inhibit SARS-CoV-2 N-induced AKI. In conclusion, the authors identify that SARS-CoV-2 N protein is a key mediator for AKI and induces AKI via the Smad3-dependent G1 cell cycle arrest mechanism. Targeting Smad3 may represent as a novel therapy for COVID-19-asscoaited AKI.

The risk of pancreatic adenocarcinoma following SARS-CoV family infection.

COVID 19 disease has become a global catastrophe over the past year that has claimed the lives of over two million people around the world. Despite the introduction of vaccines against the disease, there is still a long way to completely eradicate it. There are concerns about the complications following infection with SARS-CoV-2. This research aimed to evaluate the possible correlation between infection with SARS-CoV viruses and cancer in an in-silico study model. To do this, the relevent dataset was selected from GEO database. Identification of differentially expressed genes among defined groups including SARS-CoV, SARS-dORF6, SARS-BatSRBD, and H1N1 were screened where the |Log FC| ≥ 1and p < 0.05 were considered statistically significant. Later, the pathway enrichment analysis and gene ontology (GO) were used by Enrichr and Shiny GO databases. Evaluation with STRING online was applied to predict the functional interactions of proteins, followed by Cytoscape analysis to identify the master genes. Finally, analysis with GEPIA2 server was carried out to reveal the possible correlation between candidate genes and cancer development. The results showed that the main molecular function of up- and down-regulated genes was "double-stranded RNA binding" and actin-binding, respectively. STRING and Cytoscape analysis presented four genes, PTEN, CREB1, CASP3, and SMAD3 as the key genes involved in cancer development. According to TCGA database results, these four genes were up-regulated notably in pancreatic adenocarcinoma. Our findings suggest that pancreatic adenocarcinoma is the most probably malignancy happening after infection with SARS-CoV family.