Relevance of VEGF and CD147 in different SARS-CoV-2 positive digestive tracts characterized by thrombotic damage.

Several evidence suggests that, in addition to the respiratory tract, also the gastrointestinal tract is a main site of severe acute respiratory syndrome CoronaVirus 2 (SARS-CoV-2) infection, as an example of a multi-organ vascular damage, likely associated with poor prognosis. To assess mechanisms SARS-CoV-2 responsible of tissue infection and vascular injury, correlating with thrombotic damage, specimens of the digestive tract positive for SARS-CoV-2 nucleocapsid protein were analyzed deriving from three patients, negative to naso-oro-pharyngeal swab for SARS-CoV-2. These COVID-19-negative patients came to clinical observation due to urgent abdominal surgery that removed different sections of the digestive tract after thrombotic events. Immunohistochemical for the expression of SARS-CoV-2 combined with a panel of SARS-CoV-2 related proteins angiotensin-converting enzyme 2 receptor, cluster of differentiation 147 (CD147), human leukocyte antigen-G (HLA-G), vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 was performed. Tissue samples were also evaluated by electron microscopy for ultrastructural virus localization and cell characterization. The damage of the tissue was assessed by ultrastructural analysis. It has been observed that CD147 expression levels correlate with SARS-CoV-2 infection extent, vascular damage and an increased expression of VEGF and thrombosis. The confirmation of CD147 co-localization with SARS-CoV-2 Spike protein binding on gastrointestinal tissues and the reduction of the infection level in intestinal epithelial cells after CD147 neutralization, suggest CD147 as a possible key factor for viral susceptibility of gastrointestinal tissue. The presence of SARS-CoV-2 infection of gastrointestinal tissue might be consequently implicated in abdominal thrombosis, where VEGF might mediate the vascular damage.

Liver injury with COVID-19 based on gastrointestinal symptoms and pneumonia severity.

BACKGROUND/AIM: The coronavirus disease 2019 (COVID-19) had become a big threat worldwide. Liver injury is not uncommon in patients with COVID-19, and clarifying its characteristics is needed. This study aimed to identify factors associated with liver injury and to develop a new classification of predictive severity in patients with COVID-19. METHODS: Confirmed patients with COVID-19 (n = 60) were recruited retrospectively from Musashino Red Cross Hospital. The factors of liver injury especially on the elevation of liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) were analyzed. Grading was assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. RESULTS: During a median hospitalization follow-up of 15 (4-41) days, 51 (85.0%) patients had COVID-19 pneumonia. In clinical courses, oxygenation was needed for 25 (41.6%) patients and intubation was needed for 9 (15.0%) patients. A total of 27 (45.0%) patients had gastrointestinal symptoms (GS), such as appetite loss, diarrhea, and nausea. A logistic regression analysis revealed that C-reactive protein (CRP) at baseline, oxygenation, intubation, and GS were significant factors of liver injury. Based on these results, patients were classified into three groups: group 1, no oxygenation pneumonia; group 2, pneumonia with oxygenation or GS; and group 3, intubation. We classified 25 (41.7%), 26 (43.3%), and 9 (15.0%) patients into mild, moderate, and severe groups, respectively. The peak of AST and ALT levels was significantly stratified with this criteria (mild [median AST, 28 IU/L; median ALT, 33 IU/L], moderate [median AST, 48 IU/L; median ALT, 47.5 IU/L], and severe [median AST, 109 IU/L; median ALT, 106 IU/L]; P<0.001 and P = 0.0114, respectively). CONCLUSION: COVID-19-related liver injury was significantly stratified based on GS and severity of pneumonia.

Covid-19 and the digestive system.

The novel coronavirus disease is currently causing a major pandemic. It is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a member of the Betacoronavirus genus that also includes the SARS-CoV and Middle East respiratory syndrome coronavirus. While patients typically present with fever and a respiratory illness, some patients also report gastrointestinal symptoms such as diarrhea, vomiting, and abdominal pain. Studies have identified the SARS-CoV-2 RNA in stool specimens of infected patients, and its viral receptor angiotensin converting enzyme 2 was found to be highly expressed in gastrointestinal epithelial cells. These suggest that SARS-CoV-2 can actively infect and replicate in the gastrointestinal tract. This has important implications to the disease management, transmission, and infection control. In this article, we review the important gastrointestinal aspects of the disease.