Cyanidin-3-O-glucoside (C3G): A natural small-molecule compound for alleviating envenomation symptoms Induced by Bungarus multicinctus.

Bungarus multicinctus (many-banded krait) ranks among the world's most medically significant venomous snakes. Its venom, predominantly composed of α-bungarotoxin neurotoxins in a complex mixture, induces life-threatening respiratory paralysis, pulmonary failure, and often multi-organ dysfunction following envenomation. Building upon our discovery that the chemical dye Cy7-SE attenuates the toxicity of Bungarus multicinctus venom, this study employed network pharmacology to analyze molecular docking parameters between Cy7-SE and α-bungarotoxin. We subsequently applied computational virtual screening to identify natural small molecules alleviating symptoms of B. multicinctus envenomation, followed by comprehensive in vitro and in vivo validation. Molecular docking revealed that Cy7-SE forms a stable complex with α-bungarotoxin through five hydrogen bonds, exhibiting a binding energy of -8. 49 kcal/mol. Using optimized GridBox parameters derived from this interaction, we performed batch molecular docking against the ZINC database, identifying 3, 118, 296 potential α-bungarotoxin-binding molecules. Through sequential filtering-binding energy ≤ -7 kcal/mol, ADMET prediction analysis, Lipinski's rule screening, weighted refinement via Pandas library analysis, and final prioritization using PyMOL visualization-coupled with literature mining, the natural compound cyanidin-3-glucoside (C3G) was identified as a promising therapeutic candidate. Molecular dynamics simulations confirmed the stable binding of C3G to α-bungarotoxin. Surface plasmon resonance demonstrated that C3G and α-bungarotoxin have a strong binding affinity. In vivo studies showed that co-injection of high-dose C3G (300-fold molar equivalent to venom) with B. multicinctus venom significantly enhanced murine survival rates. Moreover, immediate post-envenomation administration of C3G at this dosage improved 24-hour survival and alleviated histopathological damage in diaphragmatic and pulmonary tissues. Notably, the protective effect of C3G relies on an extremely high molar excess and is mainly limited to co-administration or immediate post-envenomation intervention; this compound acts as a symptomatic ameliorating agent to delay disease progression and mitigate secondary tissue damage, rather than exerting direct or clinically significant venom neutralization, distinguishing it from antivenom.