RES-CMCNPs Enhance Antioxidant, Proinflammatory, and Sensitivity of Tumor Solids to γ-Irradiation in EAC-Bearing Mice.

Objectives: Resveratrol (Res) is a bifunctional compound found in numerous plants, including grapes and mulberries. Nanotechnology has promising applications in medicine. The ability of various nanomaterials to serve as radiosensitizers against tumor cells were reported in several manuscripts. The present investigation aimed to assess the antitumor and radiosensitizing effects of Res-CMCNPs on EAC-bearing mice.

Methods: Res-CMCNPs have been developed using the CMC emulsification cross-linking technique. Entrapment efficiency (%), particle size, Polydispersity index and ZETA potential, UV, FTIR spectra, and drug release were evaluated and described for RES-CMCNPs. The radiosensitizing properties of RES-CMCNPs were also evaluated in vitro and in vivo against EAC-carrying rodents. The LD50 of Res-CMCNPs was estimated and its 1/20 LD50 was prepared for treating EAC transplanted mice.

Results: The results revealed that the Res-CMCNPs exhibited a high entrapment efficiency (85.46%) and a size of approximately 184.60 ±17.36 nm with zeta potential value equals -51.866 mv. Also, the UV spectra of Res and Res-CMCNPs have strong absorption at 230 and 250 nm. The percentage of resveratrol release at pHs 5.8 and 7.4 was found to be 56.73% and 51.60 %, respectively, after 24 h at 100 rpm. Also, the FTIR analysis confirmed the chemical stability of resveratrol in Res-CMCNPs cross-linking. The IC50 values of Res-CMCNPs against EAC cells viability were 32.99, 25.46, and 22.21 µg after 24-, 48- and 72 h incubation, respectively, whereas those of ResCMCNPs in combination with γ-irradiation after 6-, 10 and 12-mins exposure were 24.07, 16.06 and 7.48 µg, respectively. Also, the LD50 of Res-CMCNPs was 2180 mg/kg.b.w. The treatment of EAC-bearing mice with Res-CMCNPs plus γ-irradiation improved plasma levels of NO, caspase-3, P53 and NF-kB levels as well as liver MDA, GSH, SOD, CAT, LT-B4, aromatase, Bax, Bcl2 and TGF-β levels and exhibited more significant anticancer activity than administration of ResCMCNPs and/or exposure to γ-irradiation individually. On the other hand, administration of ResCMCNPs in combination with γ-irradiation attenuated liver mRNAs (21, 29b, 181a, and 451) gene expression.

Conclusion: Grafting resveratrol onto carboxymethyl chitosan appears to be a promising strategy for cancer therapy as a radiosensitizer by potentiating tumor cells' sensitivity to radiation by improving levels of proinflammatory features and antioxidant biomarkers.