Influenza A virus (IAV) is a zoonotic pathogen responsible for seasonal and pandemic flu. The extensive genetic and antigenic diversity within and between IAV phylogenetic groups presents major challenges for developing universal vaccines and broad-spectrum antiviral therapies. Current interventions provide limited protection due to the virus’s high mutation rate and capacity for immune evasion. Recent advancements in viral hemagglutinin (HA)-targeting small-molecule entry inhibitors offer a promising avenue to overcome these limitations. Here, we present structural and functional analyses of two group 2 HA-specific small-molecule inhibitors recently identified by our team. Cryogenic electron microscopy (cryo-EM) structures revealed that these inhibitors bind a conserved pocket within the HA stalk, likely interfering with the conformational rearrangements necessary for membrane fusion and viral entry. Structure-guided mutagenesis confirmed the critical roles of key interacting residues and uncovered distinct resistance profiles between the two compounds, as well as in comparison to Arbidol, a previously reported HA inhibitor. Notably, our structural analysis highlights intrinsic barriers to achieving cross-group inhibition with current small-molecule designs. To address this, we propose an alternative strategy for broadening antiviral coverage. Together, these findings provide mechanistic insights into IAV entry inhibition and a foundation for the rational design of next-generation anti-influenza therapeutics.
The evergreen coniferous tree Thuja occidentalis is a member of the Cupressaceae family. This study included biological, cytotoxic, and in silico docking analyses in addition to a phytochemical composition analysis of the plant leaves and stem ethanolic extracts. The extracts’ in vitro cytotoxicity efficacy against various cancer cell lines was examined. Additionally, certain phytochemical compounds were identified by gas chromatographic analysis and subsequently assessed in silico against anticancer molecular targets. Also, their antiviral effect was assessed. Good cytotoxic activity was demonstrated by plant extracts against the lung and colorectal cancer cell lines. With half-maximal inhibitory concentration values of 18.45 μg/mL for the leaf extract and 33.61 μg/mL for the stem extract, apoptosis and S-phase arrest was observed in the lung cancer cell line. In addition, the leaf extract demonstrated effective antiviral activity, with suppression rates of 17.7 and 16.2% for the herpes simplex and influenza viruses, respectively. Gas chromatographic analysis revealed the presence of relevant bioactive components such as Podocarp-7-en-3β-ol, 13β-methyl-13-vinyl, Megastigmatrienone, and Cedrol, which were tested in silico against anticancer molecular targets. Our findings suggest that plant ethanolic extracts may have potential therapeutic uses as anticancer drugs against lung cancer in addition to their antiviral properties, which opens up further avenues for more investigation and applications.
Background and Objectives: Diabetic nephropathy (DN) is a major cause of end-stage renal disease, yet its molecular basis remains unclear. Nicotinamide adenine dinucleotide (NAD+) metabolism is crucial for energy regulation, redox balance, and inflammation. This study investigated the dysregulation of key NAD+ salvage enzymes (CD38, NAMPT, and SIRT1) across albuminuria stages in type 2 diabetes (T2D). Materials and Methods: A cross-sectional study was conducted on 225 participants: healthy controls (n = 45), T2D with normoalbuminuria (n = 60), microalbuminuria (n = 60), and macroalbuminuria (n = 60). Serum CD38, NAMPT, and SIRT1 were measured by ELISA, while CD38 and SIRT1 gene expression in peripheral blood mononuclear cells was analyzed by qPCR. Results: CD38 and NAMPT levels increased progressively with albuminuria, whereas SIRT1 levels declined significantly. CD38 and NAMPT correlated positively with HbA1c, creatinine, and urinary albumin-to-creatinine ratio (UACR), while SIRT1 showed inverse correlations and a positive association with eGFR. Regression analysis identified CD38 and NAMPT as independent positive predictors of albuminuria, and SIRT1 as a negative predictor. ROC analysis revealed strong diagnostic performance for CD38 (AUC = 0.89) and SIRT1 (AUC = 0.88). Conclusions: These findings highlight disrupted NAD+ salvage pathways in DN and suggest that restoring NAD+ balance, through CD38 inhibition, SIRT1 activation, or NAD+ precursor supplementation, may offer promising renoprotective strategies.