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Therapeutic outcome for the treatment of glioma was often limited due to the two barriers involved: the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB). Therefore, the development of nanocarriers that possess both BBB and BBTB permeability and glioma-targeting ability is of great importance for the chemotherapy of glioma. New frontiers in nanomedicine are advancing the research of new biomaterials. Here we constructed a natural high-density lipoprotein particle (HDL)-based drug delivery system with the dual-modification of T7 and dA7R peptide ligand (T7/dA7R-HDL) to achieve the above goals. HDL, the smallest lipoprotein, plays a biological role and is highly suitable as a platform for delivering imaging and therapeutic agents. T7 is a seven-peptide ligand of transferrin receptors (TfR) capable of circumventing the BBB and then targeting glioma. dA7R is a d-peptide ligand of vascular endothelial growth factor receptor 2 (VEGFR 2) overexpressed on angiogenesis, presenting excellent glioma-homing property. 10-Hydroxycamptothecin (HCPT), a hydrophobic anti-cancer drug, was used as the model drug in this study. By combining the dual-targeting delivery effect, the dual-modified HDL displayed higher glioma localization than that of single ligand-modified HDL or free HCPT. After loading with HCPT, T7/dA7R-HDL showed the most favorable anti-glioma effect in vivo. These results demonstrated that the dual-targeting natural nanocarriers strategy provides a potential method for improving brain drug delivery and anti-glioma treatment efficacy.

The effects of hormone additions at various stages and different basic media, with or without serum, on porcine oocyte maturation in vitro were studied. The results showed that the rate of maturation was not significantly different with three different stages of hormone supplement; the rate of maturation on modified TCM199 medium (54.01%) was higher than that on TCM199 (46.16%) and (47.14%), but these differences were not significant; and the rate of maturation on serum-free medium (67.10%) was significantly higher than that on medium plus serum (52.22%). Therefore, modifed tissue culture medium 199 (mTCM199)+10I U/ml pregnant mare serum gonadotrophin (PMSG)+10I U/ml human chorionic gonadotrophin (hCG)+2.5 IU/ml follicle stimulating hormone (FSH) was a suitable medium for culture of porcine oocytes in vitro, and the rate of maturation was 67.10%.