Phytochemical-mediated silver nanoparticles synthesized from Vachellia sieberiana suppress redoxinflammatory signaling in 1,2-dimethylhydrazine-induced organ toxicity

Abstract

Background: Oxidative stress and chronic inflammation are central drivers of chemically induced organ injury and colorectal carcinogenesis, particularly following exposure to 1,2-dimethylhydrazine (DMH), a potent pro-oxidant and pro-inflammatory carcinogen. Plant-mediated nanotechnology has emerged as a promising strategy to enhance the bioactivity and systemic efficacy of phytochemicals against oxido-inflammatory damage. This study investigated the protective effects of Vachellia sieberiana–functionalized silver nanoparticles (AgNPs) on DMH-induced oxidative stress and inflammation in male Wistar rats.

Methods: Silver nanoparticles were synthesized using an aqueous leaf extract of V. sieberiana and characterized by UV–visible spectroscopy, confirming nanoparticle formation with a surface plasmon resonance peak at 437 nm. Oxidative and inflammatory stress was induced by weekly subcutaneous administration of DMH (25 mg/kg) for six weeks, alongside oral treatment with V. sieberiana–AgNPs (100, 200, and 400 mg/kg). Antioxidant enzymes (GPx, GST, SOD), reduced glutathione (GSH), and malondialdehyde (MDA) were quantified in the colon, liver, and kidney, while colonic IL-6, IL-1β, and TNF-α were measured using ELISA. Data were analyzed using one-way ANOVA with Tukey’s post hoc test.

Results: DMH markedly suppressed colonic GPx (61.43%), GST (68.72%), GSH (57.07%), and SOD (42.45%), with a concomitant increase in MDA levels (39.55%, p < 0.05). Hepatic and renal tissues showed similar antioxidant depletion, including reductions in hepatic GPx (73.53%) and renal GSH (65.51%), alongside significant elevations in MDA (up to 73.25%). V. sieberiana–AgNPs dose-dependently restored antioxidant defenses and reduced lipid peroxidation, achieving MDA reductions of 54.38% in the colon and 47.15% in the kidney at 400 mg/kg (p < 0.01). DMH-induced increases in colonic IL-6 (23.42%), IL-1β (43.30%), and TNF-α (18.37%) were significantly attenuated following AgNPs treatment.

Conclusion: Vachellia sieberiana–functionalized silver nanoparticles confer significant protection against DMH-induced oxidative stress and inflammatory injury, highlighting their potential as phytochemical-based nanotherapeutics for managing chemically induced tissue damage.