Resveratrol-loaded polymeric nanoparticles suppress glucose metabolism and tumor growth in vitro and in vivo

Resveratrol (RSV) is a natural phenol with promising anti-tumor activities, but its use for in vivo cancer treatment is limited by low aqueous solubility and poor stability. In this study, we prepared RSV-loaded polyethylene glycol-polylactic acid (PEG-PLA; M.W. 5000-5000) polymer nanoparticles (NPs) for improved stability and controlled delivery, and investigated its metabolic and anti-tumor effect in vitro and in vivo. CT26 colon cancer cells displayed significantly reduced cell number to 5.6% and colony forming capacity to 6.3% of controls by 72 h treatment with 40 and 20 μM of RSV-NP, respectively. Flow cytometry and western blots demonstrated increased apoptotic cell death, and ¹⁸F FDG uptake and reactive oxygen species was significantly reduced by RSV-NP. All of these effects were comparable to or greater in potency compared to free RSV. When RSV-NP was intravenously administered to CT26 tumor bearing mice, there was a reduction of ¹⁸F FDG uptake on PET/CT by day 4. Longer treatment led to retardation of tumor growth accompanied by an improvement in survival compared to empty NP-injected controls. These results demonstrate that the in vitro and in vivo metabolic and anti-tumor effects of RSV is preserved by PEG-PLA NP loading, and provide an encouraging outlook on the potential of polymeric NPs as an effective method to deliver RSV for cancer therapy.