Application Of LAT1-Modified Co-Loaded Nanoparticles In Targeted Treatment Of Glioma

Objective(s): In this study,LAT1 was used as the target and PLGA as the drug carrier to prepare L-STNP co-loading Temozolomide(TMZ)and sorafenib,and L-STNP explored its inhibitory effects on glioma and its potential mechanisms.Method(s): L-STNP was synthesized by nano-precipitation method,and the particle size,Zeta potential and morphology were characterizend by dynamic light scattering(DLS)and transmission electron microscope(TEM).The loading and the cumulative release rate of TMZ were detected by(high performance liquid)HPLC and ultraviolet spectrophotometer.The cell viability of L-STNP on U87 cells was detected by CCK8.Apoptosis was analyzed by apoptosis kit.Intracellular ROS levels were measured by the DCFH-DA fluorescent probe.The intracellular GSH level was detected by GSH kit.The expression of GPX4,a marker protein of ferroptosis,was detected by Western blot.In vivo experiments showed that L-STNP significantly inhibited tumor growth and prolonged survival time in subcutaneous tumor-bearing nude mice;HE results showed no significant changes in liver and kidney in each administration group,indicating that L-STNP was not significantly toxic to xenograft tumors;TUNEL experiments also showed the highest degree of apoptosis in tumor cells in the L-STNP group;Immunofluorescence results showed that LSTNP reduced the expression level of GPX4 protein in tumor tissues.The immunofluorescence results showed that L-STNP reduced the expression level of GPX4 protein in the tumor tissue.The further molecular biological mechanism is consistent with the cellular experiments.Result(s): L-STNP is a spherical nanoparticle with uniform morphology and determined by dynamic light scattering is 95 nm.The potential was-36.3 ±1.6 m V,the encapsulation rate and loading rate of Temozolomide were(65.34 ± 1.43)% and(3.35 ± 2.81)%,and that of sorafenib were(36.86 ± 1.3)% and(4.13 ± 0.19)%.Hemolysis experiment showed good biological safety.In the cell uptake experiment,the fluorescence intensity of L-NP was significantly higher than that of N-NP,and the results of FACS and confocal showed that L-NP had strong targeting properties on U87 cells.Compared with L-SNP,L-TNP,and SNTP,L-SNTP showed greater toxicity in U87 cells,significantly increasing the intracellular ROS level,decreasing the intracellular GSH level,and decreasing the expression level of GPX4,a marker of ferroptosis.In vivo experiments showed that L-STNP significantly inhibited the tumor growth and prolonged the survival time of nude mice with subcutaneous tumor.H&E results showed no significant changes in liver and kidney in each administration group,indicating that L-STNP had no obvious toxicity to xenogenic tumors.TUNEL staining also de that L-STNP group had the highest apoptosis rate.Immunofluorescence results showed that L-STNP reduced the expression level of GPX4 protein in tumor tissues.The further molecular biological mechanism is consistent with cell experiment.Conclusion(s): In this study,tyrosine-modified polyethylene glycol stearate LAT1-targeted nanoparticles co-loading TMZ and sorafenib(LSTNP),were successfully constructed to reach glioma through the bloodbrain barrier and achieve effective accumulation in brain tissue.In vitro and in vivo results showed that L-STNP had good drug loading,drug release ability and biosafety,and could significantly inhibit tumor growth.Further study showed that the nanoparticles could inhibit glioma by inducing apoptosis and ferroptosis.Our study provides the basis for amino acid transporter mediated nano-delivery system for glioma therapy.