Salvianolic acid B for COVID-19

Introduction Coronavirus disease 2019 (COVID-19) is an epidemic respiratory disease caused due to the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In China, the National Health Commission of China announced that patients with COVID-19 who were treated with traditional Chinese medicines (TCMs) combined with antiviral drugs effectively alleviated their symptoms and recovered. Among these TCMs, Xuebijing (XBJ) injection plays an important role in the treatment of patients with COVID-19. However, this was a puzzle that what will be the clinical efficacy and safety of XBJ injection for COVID-19 treatment, and what are the potential mechanisms behind XBJ injection? Methods To search for articles on “Xuebijing injection in the treatment of COVID-19” in PubMed, use the following query: (Xuebijing injection OR Xuebijing) AND (COVID-19 OR SARS-CoV-2 OR severe pneumonia). We added filters for “Clinical Trial,” “Randomized Controlled Trial,” or “Review” to focus on specific study types, and limit the search to recent years (2010–2025) and English-language articles for more targeted results. Results XBJ injection in combination with regular therapy has been shown to improve overall efficacy, reduce 28-day mortality, improve lung CT recovery and reduce pro-inflammatory markers in patients with COVID-19. The high affinity for angiotensin converting enzyme 2, inhibition of neutrophil extracellular trap release and prevention of cell death and inflammation may be the main molecular mechanisms of XBJ injection in the treatment of COVID-19. Conclusion This review synthesizes the current evidence on the clinical efficacy and safety of XBJ injection in the treatment of COVID-19. Our analysis indicates that XBJ injection, when used in combination with standard therapy, significantly improves overall efficacy, reduces 28-day mortality, enhances lung CT recovery, and decreases pro-inflammatory markers such as C-reactive protein (CRP) and interleukin-6 (IL-6). These findings suggest that Xuebijing injection is a promising adjunctive treatment for COVID-19, particularly in severe cases, although it must be confirmed through rigorous pharmacological and clinical studies.

In this in silico study, we conducted an in-depth exploration of the potential of natural products and antihypertensive molecules that could serve as inhibitors targeting the key proteins of the SARS-CoV-2 virus: the main protease (Mpro) and the spike (S) protein. By utilizing Induced Fit Docking (IFD), we assessed the binding affinities of the molecules under study to these crucial viral components. To further comprehend the stability and molecular interactions of the “protein-ligand” complexes that derived from docking studies, we performed molecular dynamics (MD) simulations, shedding light on the molecular basis of potential drug candidates for COVID-19 treatment. Moreover, we employed Molecular Mechanics Generalized Born Surface Area (MM-GBSA) calculations on all “protein-ligand” complexes, underscoring the robust binding capabilities of rosmarinic acid, curcumin, and quercetin against Mpro, and salvianolic acid b, rosmarinic acid, and quercetin toward the S protein. Furthermore, in order to expand our search for potent inhibitors, we conducted a structure similarity analysis, using the Enalos Suite, based on the molecules that indicated the most favored results in the in silico studies. The Enalos Suite generated 115 structurally similar compounds to salvianolic acid, rosmarinic acid, and quercetin. These compounds underwent IFD calculations, leading to the identification of two salvianolic acid analogues that exhibited strong binding to all the examined binding sites in both proteins, showcasing their potential as multi-target inhibitors. These findings introduce exciting possibilities for the development of novel therapeutic agents aiming to effectively disrupt the SARS-CoV-2 virus lifecycle.

The COVID-19 pandemic has stimulated collaborative drug discovery efforts in academia and the industry with the aim of developing therapies and vaccines that target SARS-CoV-2. Several novel therapies have been approved and deployed in the last three years. However, their clinical application has revealed limitations due to the rapid emergence of viral variants. Therefore, the development of next-generation SARS-CoV-2 therapeutic agents with a high potency and safety profile remains a high priority for global health. Increasing awareness of the “back to nature” approach for improving human health has prompted renewed interest in natural products, especially dietary polyphenols, as an additional therapeutic strategy to treat SARS-CoV-2 patients, owing to its good safety profile, exceptional nutritional value, health-promoting benefits (including potential antiviral properties), affordability, and availability. Herein, we describe the biological properties and pleiotropic molecular mechanisms of dietary polyphenols curcumin, resveratrol, and gossypol as inhibitors against SARS-CoV-2 and its variants as observed in in vitro and in vivo studies. Based on the advantages and disadvantages of dietary polyphenols and to obtain maximal benefits, several strategies such as nanotechnology (e.g., curcumin-incorporated nanofibrous membranes with antibacterial-antiviral ability), lead optimization (e.g., a methylated analog of curcumin), combination therapies (e.g., a specific combination of plant extracts and micronutrients), and broad-spectrum activities (e.g., gossypol broadly inhibits coronaviruses) have also been emphasized as positive factors in the facilitation of anti-SARS-CoV-2 drug development to support effective long-term pandemic management and control.