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1.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-1005359

RÉSUMÉ

The key pathogenesis of coronary heart disease (CHD) is spleen deficiency and phlegm stasis, and dysfunctional high-density lipoprotein (dys-HDL) may be the biological basis for the occurrence of CHD due to spleen deficiency and phlegm stasis. Considering the biological properties and effects of high-density lipoprotein (HDL), it is believed that the structure and components of HDL are abnormal in the state of spleen deficiency which led to dys-HDL; and dys-HDL contributes to the formation of atherosclerotic plaques through two major pathways, namely, mediating the dysfunction of endothelial cells and mediating the foaminess of macrophages and smooth muscle cells, thus triggering the development of CHD. It is also believed that dys-HDL is a microcosmic manifestation and a pathological product of spleen deficiency, and spleen deficiency makes foundation for the production of dys-HDL; dys-HDL is also an important biological basis for the phlegm-stasis interactions in CHD. The method of fortifying spleen, resolving phlegm, and dispelling stasis, is proposed as an important principle in the treatment of CHD by traditional Chinese medicine, which can achieve the therapeutic purpose by affecting the changes in the structure and components of dys-HDL, thus revealing the scientific connotation of this method, and providing ideas for the diagnosis and treatment of CHD by traditional Chinese medicine.

2.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-518418

RÉSUMÉ

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, much effort has been dedicated to identifying effective antivirals against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A number of calpain inhibitors show excellent antiviral activities against SARS-CoV-2 by targeting the viral main protease (Mpro), which plays an essential role in processing viral polyproteins. In this study, we found that calpain inhibitors potently inhibited the infection of a chimeric vesicular stomatitis virus (VSV) encoding the SARS-CoV-2 spike protein, but not Mpro. In contrast, calpain inhibitors did not exhibit antiviral activities towards the wild-type VSV with its native glycoprotein. Genetic knockout of calpain-2 by CRISPR/Cas9 conferred resistance of the host cells to the chimeric VSV-SARS-CoV-2 virus and a clinical isolate of wild-type SARS-CoV-2. Mechanistically, calpain-2 facilitates SARS-CoV-2 spike protein-mediated cell attachment by positively regulating the cell surface levels of ACE2. These results highlight an Mpro-independent pathway targeted by calpain inhibitors for efficient viral inhibition. We also identify calpain-2 as a novel host factor and a potential therapeutic target responsible for SARS-CoV-2 infection at the entry step.

3.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-487939

RÉSUMÉ

Omicron B.1.1.529 became the predominant SARS-CoV-2 variant in early 2022, causing a new wave of public anxiety. Compared to the ancestral strain, Omicron has 50 mutations, with over 30 mutations in the spike protein. These differences likely underlie the changes in Omicron biology noted in other studies, including an attenuation in the lung parenchyma, compared to the ancestral SARS-CoV-2 strain and other variants, as well as a preference for endosomal entry, in place of the TMPRSS2-mediated membrane fusion pathway. This raises questions on Omicron tropism and infectivity in various target organ systems, including the gastrointestinal (GI) tract. Up to 70% of COVID-19 patients report GI symptoms, including nausea, vomiting, and diarrhea. Here, we show that in the context of donor intrinsic genetic heterogeneity, the SARS-CoV-2 Omicron variant infects human colonoids similarly, if not less effectively, than the ancestral WT (WA1) strain or the Delta variant. Additionally, we note a higher ratio of viral RNA to infectious virus titer, which may suggest that Omicron is potentially less infectious in the intestine. This study lays the foundation for further work defining mechanisms mediating intestinal infection and pathogenesis by Omicron.

4.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-453393

RÉSUMÉ

IntroductionCoronavirus Disease 2019 (COVID-19) is an ongoing public health crisis that has sickened or precipitated death in millions. The etiologic agent of COVID-19, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), infects the intestinal epithelium, and can induce GI symptoms similar to the human inflammatory bowel diseases (IBD). An international surveillance epidemiology study (SECURE-IBD) reported that the standardized mortality ratio trends higher in IBD patients (1.5-1.8) and that mesalamine/sulfasalazine therapy correlates with poor outcome. The goal of our study was to experimentally address the relationship between mesalamine and SARS-CoV-2 entry, replication, and/or pathogenesis. MethodsViral infection was performed with a chimeric vesicular stomatitis virus expressing SARS-CoV-2 spike protein and EGFP (VSV-SARS-CoV-2) and SARS-CoV-2 virus derived from an infectious cDNA clone of 2019n-CoV/USA_WA1/2020. Primary human ileal spheroids derived from healthy donors were grown as 3D spheroids or on 2D transwells. We assessed the effect of 10 mM mesalamine (Millipore Sigma) on viral RNA levels, as well as the expression of the SARS-CoV-2 receptor angiotensin II-converting enzyme 2 (ACE2), Transmembrane Serine Protease 2 (TMPRSS2), TMPRSS4, Cathepsin B (CTSB) and CTSL by qRT-PCR. 8-12 week old K18-ACE2 were treated orally with PBS or mesalamine at 200 mg/kg daily. Mice were inoculated intranasally with 1x103 FFU of SARS-CoV-2. Mice were weighed daily and viral titers were determined 7 days post infection (dpi) by qRT-PCR. For the intestinal viral entry model, VSV-SARS-CoV-2 was injected into a ligated intestinal loop of anesthetized K18-ACE2 mice and tissues were harvested 6 hours post-infection. ResultsWe found no change in viral RNA levels in human intestinal epithelial cells in response to mesalamine. Expression of ACE2 was reduced following mesalamine treatment in enteroids, while CTSL expression was increased. Mice receiving mesalamine lost weight at similar rates compared to mice receiving vehicle control. Mesalamine treatment did not change viral load in the lung, heart, or intestinal tissues harvested at 7 dpi. Pretreatment with mesalamine did not modulate intestinal entry of the chimeric VSV-SARS-CoV-2 in K18-ACE2 mice. ConclusionsMesalamine did not alter viral entry, replication, or pathogenesis in vitro or in mouse models. Mesalamine treatment reduced expression of the viral receptor ACE2 while concurrently increasing CTSL expression in human ileum organoids.

5.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-312165

RÉSUMÉ

Pathogenic coronaviruses represent a major threat to global public health. Here, using a recombinant reporter virus-based compound screening approach, we identified several small-molecule inhibitors that potently block the replication of the newly emerged severe acute respiratory syndrome virus 2 (SARS-CoV-2). Among them, JIB-04 inhibited SARS-CoV-2 replication in Vero E6 cells with an EC50 of 695 nM, with a specificity index of greater than 1,000. JIB-04 showed in vitro antiviral activity in multiple cell types against several DNA and RNA viruses, including porcine coronavirus transmissible gastroenteritis virus. In an in vivo porcine model of coronavirus infection, administration of JIB-04 reduced virus infection and associated tissue pathology, which resulted in improved weight gain and survival. These results highlight the potential utility of JIB-04 as an antiviral agent against SARS-CoV-2 and other viral pathogens.

6.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-141077

RÉSUMÉ

Cholesterol 25-hydroxylase (CH25H) is an interferon-stimulated gene (ISG) that shows broad antiviral activities against a wide range of enveloped viruses. Here, using an ISG screen against VSV-SARS-CoV and VSV-SARS-CoV-2 chimeric viruses, we identified CH25H and its enzymatic product 25-hydroxycholesterol (25HC) as potent inhibitors of virus replication. Mechanistically, internalized 25HC accumulates in the late endosomes and blocks cholesterol export, thereby restricting SARS-CoV-2 spike protein catalyzed membrane fusion. Our results highlight a unique antiviral mechanism of 25HC and provide the molecular basis for its possible therapeutic development.

7.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-102038

RÉSUMÉ

Antibody-based interventions against SARS-CoV-2 could limit morbidity, mortality, and possibly disrupt epidemic transmission. An anticipated correlate of such countermeasures is the level of neutralizing antibodies against the SARS-CoV-2 spike protein, yet there is no consensus as to which assay should be used for such measurements. Using an infectious molecular clone of vesicular stomatitis virus (VSV) that expresses eGFP as a marker of infection, we replaced the glycoprotein gene (G) with the spike protein of SARS-CoV-2 (VSV-eGFP-SARS-CoV-2) and developed a high-throughput imaging-based neutralization assay at biosafety level 2. We also developed a focus reduction neutralization test with a clinical isolate of SARS-CoV-2 at biosafety level 3. We compared the neutralizing activities of monoclonal and polyclonal antibody preparations, as well as ACE2-Fc soluble decoy protein in both assays and find an exceptionally high degree of concordance. The two assays will help define correlates of protection for antibody-based countermeasures including therapeutic antibodies, immune {gamma}-globulin or plasma preparations, and vaccines against SARS-CoV-2. Replication-competent VSV-eGFP-SARS-CoV-2 provides a rapid assay for testing inhibitors of SARS-CoV-2 mediated entry that can be performed in 7.5 hours under reduced biosafety containment.

8.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-054015

RÉSUMÉ

Both gastrointestinal symptoms and fecal shedding of SARS-CoV-2 RNA have been frequently observed in COVID-19 patients. However, whether SARS-CoV-2 replicate in the human intestine and its clinical relevance to potential fecal-oral transmission remain unclear. Here, we demonstrate productive infection of SARS-CoV-2 in ACE2+ mature enterocytes in human small intestinal enteroids. In addition to TMPRSS2, another mucosa-specific serine protease, TMPRSS4, also enhanced SARS-CoV-2 spike fusogenic activity and mediated viral entry into host cells. However, newly synthesized viruses released into the intestinal lumen were rapidly inactivated by human colonic fluids and no infectious virus was recovered from the stool specimens of COVID-19 patients. Our results highlight the intestine as a potential site of SARS-CoV-2 replication, which may contribute to local and systemic illness and overall disease progression.

9.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-469402

RÉSUMÉ

Objective To explore the mediating role of self-esteem in optimism and suicidal risks,and the moderate effect of life events in optimism,suicidal risk and self-esteem.Methods 1 750 college students were surveyed with the life orientation test-revised (LOT-R),the suicidal behaviors questionnaire-revised (SBQ-R),rosenberg self-esteem scale(SES) and adolescent self-rating life events check list (ASLEC).Results The total scores of SBQ-R,LOT-R,SES and ASLEC of college students were (4.78±2.10),(23.17±3.22),(29.58±4.43)and (36.54±21.73).Optimism scores were negatively correlated with suicidal risk scores(r=-0.23,P<0.01),optimism scores were positively correlated with self-esteem (r=0.50,P<0.01).Scores of self-esteem scales were negatively correlated with suicidal risk scores(r=-0.35,P<0.01).A structure equation model consists of optimism,self-esteem,suicidal risk and it had a better degree of fitting (the path form optimism to suicidal risk were r =-0.05,P<0.05,RMSEA =0.05,GFI =0.90,NFI =0.92,CFI =0.93).The relationship between optimism and suicide risk were mediated by self-esteem(P<0.01),which accounted for 76%of the total effects.The life events' moderating effects between self-esteem and suicide risk were significant(P<0.01).Conclusion Self-esteem has a significant correlation with optimism and suicidal behaviors,self-esteem plays an intermediary role between optimism and suicidal behaviors,and life events play an regulation role between self-esteem and suicidal behaviors.

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