CD44-targeted NLCs improve trans -resveratrol in vitro cellular uptake and cytotoxicity in high-grade glioma cells.

High-grade gliomas are aggressive brain tumors associated with poor prognosis and a short median survival. Despite a multi-modal therapy, including surgical resection, and adjuvant radio and chemotherapy, few advances were achieved in the clinics. The urgent need for new therapeutic strategies to treat brain tumor has driven the development of innovative drug delivery technologies such as nanostructured lipid carriers (NLCs). NLCs have demonstrated significant potential in cancer therapy, particularly due to improvements in the delivery of poorly soluble drugs, with promising anti-tumor potential, such as the polyphenol trans-resveratrol (RSV). This study aimed to develop and evaluate the in vitro biological properties of NLCs loaded with RSV and functionalized with hyaluronic acid (HA) for targeted delivery to CD-44-expressing glioma cells. NLCs were produced using the fusion-emulsification technique followed by sonication, and NLC-RSVs were functionalized with HA through physicochemical adsorption. NLCs were characterized in terms of hydrodynamic diameter, polydispersity index (PDI), and zeta potential, and further analyzed by differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). Encapsulation efficiency (EE%) and the in vitro drug release profile were determined by high-performance liquid chromatography (HPLC). Cytotoxicity was assessed in C6 glioma cells using the resazurin reduction assay. The NLC-RSV formulations exhibited an average size of 160.5 nm, a PDI of 0.36, and a zeta potential of + 21.85 mV. Functionalization was performed using HA at 0.5 mg/mL in a 2:1 (v/v) HA:NLC ratio. The EE% of the HA-NLC-RSV formulation was 88.98 ± 0.55 %. FTIR analysis confirmed the presence of HA and indicated successful interaction of HA with the lipid matrix. DSC data suggested that RSV was effectively encapsulated and protected within the lipid matrix. The in vitro release study revealed that HA functionalization provided a slower and more controlled drug release. Cytotoxicity assays demonstrated that HA functionalization enhanced the antiproliferative effect, with the RSV-HA-NLC formulation displaying the most potent effect. This finding was supported by increased cellular uptake of HA-NLCs in C6 cells. These results indicate that HA-functionalized NLCs represent a promising strategy to improve the solubility and targeted delivery of poorly soluble drugs such as RSV. By enabling more effective delivery of RSV to glioma cells, this approach may help advance our understanding of RSV's biological effects in cancer and encourage further investigation of their biological properties using in vivo models.