Green Synthesized Resveratrol-Stabilized Silver Nanoparticles Induce Developmental Toxicity and Gene Expression Changes in Zebrafish

The aim of the present study was to synthesise silver nanoparticles (Res-AgNPs) using a green chemistry approach with resveratrol as a natural reducing and stabilizing agent, and to evaluate its effect on zebrafish embryos. Nanoparticle formation was confirmed by UV–visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD), showing a characteristic surface plasmon resonance peak at 435 nm, involvement of hydroxyl and carbonyl functional groups in stabilization, and a crystalline silver phase, respectively. Zebrafish embryos were exposed to Res-AgNPs at concentrations ranging from 1 to 50 µg/mL and assessed at 24, 48, 72, and 96 hours post-fertilization (hpf) for survival, hatching rate, morphological abnormalities, and growth parameters. Higher nanoparticle concentrations resulted in significant alterations in heart rate, spontaneous movement, and body length. Quantitative real-time PCR analysis demonstrated dose-dependent modulation of oxidative stress–related genes (sod1, cat, gstp2), apoptosis-associated markers (bax, bcl-2, caspase-3), and key developmental regulators (shh, notch1a, wnt8a, bmp2b). Although Res-AgNPs synthesized via a biogenic route exhibited controlled physicochemical characteristics, elevated concentrations induced oxidative imbalance and developmental perturbations in zebrafish embryos. These findings emphasized the importance of concentration-dependent toxicity evaluation for green-synthesized nanomaterials and reinforced the zebrafish embryo as a sensitive vertebrate model for nanotoxicological assessment.