Yinyanghuo () and its components for chronic obstructive pulmonary disease: preclinical evidence and possible mechanisms.

OBJECTIVE: To integrate Meta-analysis and bioinformatics strategies in the preliminary exploration of the potential mechanism of Yinyanghuo () and its extract in treating chronic obstructive pulmonary disease (COPD). METHODS: First, Meta-analysis was carried out. The Chinese and English literature of Yinyanghuo () in treating COPD was searched using the systematic strategy of combining subject words with free words. The included studies were evaluated by the SYRCLE risk bias assessment tool, after which the review manager software was used to combine the effect quantities for statistical analysis. Then, based on bioinformatics technology, the active ingredients and their targets of Yinyanghuo () were screened, and the intersection genes were obtained by mapping and comparing with the targets of COPD. The "medicinal materials-compounds-targets model" was constructed, and the key pathways were annotated. Finally, the core target was docked with important compounds. RESULTS: A total of 8 studies were included in the Meta-analysis. The results showed that the Yinyanghuo (Herba Epimedii Brevicornus) group could significantly down-regulate pro-inflammatory factors such as tumor necrosis factor-α (TNF-α) and interleukin (IL)-8 and increase the expression of anti-inflammatory factors and antioxidant factors such as IL-10 and phospho-protein kinase B (p-AKT) in the COPD model (all P < 0.05). A total of 23 active components and 102 corresponding target genes of Yinyanghuo (Herba Epimedii Brevicornus) were obtained by bioinformatics technology, among which 17 compounds and 63 targets were closely related to COPD. The results of enrichment analysis mainly included TNF signaling pathway, phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, cancer signaling pathway, and other inflammatory reactions, oxidative stress, and tumor-related pathways. The molecular docking results showed that the binding energy fractions of the top five components of 24-epicampesterol with 10 core targets such as IL-6 were all less than ï¹£5.0 kcal/mol, suggesting good binding ability. CONCLUSIONS: Meta-analysis and bioinformatics results indicated that the therapeutic effect of Yinyanghuo () and its components on COPD might be related to antagonizing inflammation and oxidative stress. The above findings provide a preliminary basis for the development of Yinyanghuo () as a natural drug for preventing and treating COPD.

Structural and functional characterizations of altered infectivity and immune evasion of SARS-CoV-2 Omicron variant

The SARS-CoV-2 Omicron with increased fitness is spreading rapidly worldwide. Analysis of cryo-EM structures of the Spike (S) from Omicron reveals amino acid substitutions forging new interactions that stably maintain an "active" conformation for receptor recognition. The relatively more compact domain organization confers improved stability and enhances attachment but compromises the efficiency of viral fusion step. Alterations in local conformation, charge and hydrophobic microenvironments underpin the modulation of the epitopes such that they are not recognized by most NTD- and RBD-antibodies, facilitating viral immune escape. Apart from already existing mutations, we have identified three new immune escape sites: 1) Q493R, 2) G446S and 3) S371L/S373P/S375F that confers greater resistance to five of the six classes of RBD-antibodies. Structure of the Omicron S bound with human ACE2, together with analysis of sequence conservation in ACE2 binding region of 25 sarbecovirus members as well as heatmaps of the immunogenic sites and their corresponding mutational frequencies sheds light on conserved and structurally restrained regions that can be used for the development of broad-spectrum vaccines and therapeutics.