Immunomodulation of macrophages by methylglyoxal conjugated with chitosan nanoparticles against Sarcoma-180 tumor in mice

•We developed a methylglyoxal chitosan conjugate called ‘Nano-MG’.•This compound has anticancer and immunomodulatory role.•Nano-MG reduced murine Sarcoma-180 tumor volume.•Nano-MG upregulated macrophage cytokines in tumor bearing mice.

Methylglyoxal (MG), the potent anticancer agent has been conjugated to a nontoxic, biocompatible polymer, chitosan, to protect it from in vivo enzymatic degradation. This polymeric complex, ‘Nano-MG’ shows remarkable antitumor property and elicits macrophage-mediated immunity in tumor bearing mice on intravenous (0.4 mg/kg body wt/day) treatment more efficiently than MG (20 mg/kg body wt/day). These activated macrophages appear more in numbers in the peritoneum and produce more superoxide and nitrite. Moreover, immunomodulatory cytokines and surface receptors of these macrophages like iNOS, IFN-γ, TNF-α, IL-1β, IL-6, M-CSF, TLR-4 and TLR-9 also exhibit marked up-regulation in Sarcoma-180 tumor bearing mice after Nano-MG treatment compared to untreated tumor bearing counterpart. Hence, Nano-MG acts as an immunostimulant in tumor bearing mice to combat cancer at conspicuously lower dose, probably due to its longer circulation time in blood.