Indirubin for COVID-19

Background The global outbreak of coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has raised significant public health concerns. Qingyan Dropping Pills (QDP), as a recommended drug, is issued by the National Health Commission of the People’s Republic of China for the treatment of COVID-19. However, its bioactive compounds and their mechanisms of action remain largely unidentified. In this study, the integration of computational and experimental approaches was performed to identify the bioactive compounds in QDP and elucidate its mechanisms against COVID-19. Methods Utilizing UPLC-Q/TOF-MS, the chemical compounds of QDP were delineated, followed by network pharmacology analysis and molecular docking targeting SARS-CoV-2 spike protein (S pro ), main protease (M pro ), and papain-like protease (PL pro ). To validate the inhibitory activity of these compounds, fluorescence resonance energy transfer (FRET) and surface plasmon resonance (SPR) assays were employed. The antivival efficacy was tested in Vero E6 cells infected with SARS-CoV-2 Omicron BA.5 variant. Moreover, anti-inflammatory potential was evaluated via the measurement of inflammatory markers, including nitric oxide (NO), interleukin-6 (IL-6), interleukin-1 beta (IL-1 β ), and tumor necrosis factor-alpha (TNF- α ). Results Among the 48 identified compounds, 33 demonstrated potential antiviral activity against COVID-19. Notably, Hamamelitannin (HAM), corilagin (COR), and rhoifolin (RHO) effectively interacted with S pro , M pro and PL pro in silico . In SPR assays, the equilibrium dissociation constant ( K D ) for COR and RHO ranged from 4.515 × 10 −8 M to 7.718 × 10 −6 M, while HAM showed strong binding affinity to S pro ( K D = 9.33 × 10 −8 M) but weaker affinity for M pro and PL pro . In FRET assays, COR and RHO inhibited..

Background/Objectives: Coronavirus disease 2019 (COVID-19) has been a global pandemic since 2019, but effective therapeutic treatments for it remain limited. Shuqing Granule (SG) is a traditional Chinese medicine containing ingredients such as indirubin, shinpterocarpin, naringenin, and quercetin. It exhibits anti-inflammatory and antiviral activities as well as broad-spectrum antiviral effects, yet its potential role in the treatment of COVID-19 remains unclear. This study thus aimed to explore the therapeutic effects of SG on COVID-19, with a focus on its potential anti-SARS-CoV-2 activity linked to these bioactive ingredients. Methods: The potential therapeutic ability of SG was investigated by combining network pharmacology, molecular docking, and experimental verification. First, key ingredients in SG and their corresponding targets, as well as COVID-19-related targets, were identified. Then, enrichment analyses were performed to highlight potential key pathways. Additionally, molecular docking was conducted to assess the binding capacity of the key ingredients to ACE2. Finally, experiments such as Western blot and ELISA were conducted to verify the effect of SG. Results: The results showed that 15 key ingredients such as quercetin in SG could affect overlapping targets such as RELA. Molecular docking results showed that key ingredients in SG, such as isoliquiritigenin, formononetin, shinpterocarpin, indirubin, naringenin, kaempferol, and 7-Methoxy-2-methylisoflavone, might bind to angiotensin-converting enzyme II (ACE2)—a critical receptor in the process of COVID-19 infection—thereby exerting antiviral effects. Experiments such as Western blot and ELISA further demonstrated that SG could reduce inflammation induced by the SARS-CoV-2 S1 protein by 50%. This effect might be achieved by downregulating ACE2 expression by 1.5 times and inhibiting the NF-κB signaling pathway. Conclusions: This study confirmed that SG has potential as a candidate for COVID-19 treatment. It also provided a new approach for the application of traditional Chinese medicine in combating the virus.

The sudden rise of the SARS-CoV-2 virus and the delay in development of effective therapeutics for mitigation made evident a need for ways to screen compounds that can block infection and prevent further pathogenesis and spread. However, identifying effective drugs that are efficacious against viral infection and replication with minimal toxicity for the patient can be difficult. Monoclonal antibodies were shown to be effective, but as the SARS-CoV-2 mutated, these antibodies became ineffective. Small-molecule antivirals were identified using pseudovirus constructs to recapitulate infection in nonhuman cells, such as Vero E6 cells. However, the impact was limited due to poor translation of these compounds in the clinical setting. This is partly due to the lack of similarity of screening platforms to the in vivo physiology of the patient and partly because drugs effective in vitro showed dose-limiting toxicities. In this study, we performed two high-throughput screens in human lung adenocarcinoma cells with authentic SARS-CoV-2 virus to identify both monoclonal antibodies that neutralize the virus and clinically useful kinase inhibitors to block the virus and prioritize minimal host toxicity. Using high-content imaging combined with single-cell and multidimensional analysis, we identified antibodies and kinase inhibitors that reduce viral infection without affecting the host. Our screening technique uncovered novel antibodies and overlooked kinase inhibitors (i.e., PIK3i, mTORi, and multiple RTKi) that could be effective against the SARS-CoV-2 virus. Further characterization of these molecules will streamline the repurposing of compounds for the treatment of future pandemics and uncover novel mechanisms viruses use to hijack and infect host cells.

AbstractTo attain promising pharmacotherapies, researchers have applied drug repurposing (DR) techniques to discover the candidate medicines to combat the coronavirus disease 2019 (COVID-19) outbreak. Although many DR approaches have been introduced for treating different diseases, only structure-based DR (SBDR) methods can be employed as the first therapeutic option against the COVID-19 pandemic because they rely on the rudimentary information about the diseases such as the sequence of the severe acute respiratory syndrome coronavirus 2 genome. Hence, to try out new treatments for the disease, the first attempts have been made based on the SBDR methods which seem to be among the proper choices for discovering the potential medications against the emerging and re-emerging infectious diseases. Given the importance of SBDR approaches, in the present review, well-known SBDR methods are summarized, and their merits are investigated. Then, the databases and software applications, utilized for repurposing the drugs against COVID-19, are introduced. Besides, the identified drugs are categorized based on their targets. Finally, a comparison is made between the SBDR approaches and other DR methods, and some possible future directions are proposed.