Abstract
Gum arabic-conjugated gold nanoparticles (GA-AuNPs; 15–18nm) have been previously well characterised in vitro and in vivo for their stability; however, their cytotoxicity and pharmacological effects, with and without laser exposure, is largely unknown.
We investigated the cytotoxicity of GA-AuNPs in A549 lung cancer cells and the change in inflammatory cytokine, death receptors, lipid peroxidation, apoptosis mediators, and histopathological changes in lung tumour-bearing mice with or without laser irradiation.
In-vitro studies showed that GA-AuNPs with laser irradiation had significant cytotoxicity against A549 cells, while they had no cytotoxicity in the absence of laser. Gum arabic is cellularly safe in the absence or presence of laser irradiation. In-vivo studies showed that GA-AuNPs with laser resulted in significant alterations in lung tumours in mice, inducing apoptosis through upregulation of caspase-3, death receptor (DR5), and enhanced release of cytochrome C. Treatment with GA-AuNPs and laser inhibited the induction of TNF-α and VEGF in tumour-bearing mice and increased lipid peroxidation. Gum arabic was biologically inactive expect when combined with laser irradiation in healthy and in tumour-bearing mice, where it led to elevated lipid peroxidation.
Gum arabic and GA-AuNPs separately are safe. Co-administration of GA-AuNPs with laser irradiation induced cytotoxicity, apoptosis, decreased inflammation and angiogenesis, and enhanced lipid peroxidation.