RESUMO
Owing to the complexity of tumor treatment, clinical tumor treatment has evolved from a single treatment mode to multiple combined treatment modes. Reducing the tolerance of tumors to heat and the toxicity of chemotherapy drugs to the body, as well as increasing the sensitivity of tumors to photothermal therapy and chemotherapy drugs, are key issues that urgently need to be addressed in the current cancer treatment. In this work, polylactic acid-based drug nanoparticles (PLA@DOX/GA/ICG) were synthesized with good photothermal conversion ability by encapsulating the water-soluble anticancer drug doxorubicin (DOX), photothermal conversion agent indocyanine green (ICG) and liposoluble drug gambogic acid (GA) using a double emulsion method. The preparation process of PLA@DOX/GA/ICG was examined. Gambogic acid entrapped in PLA@DOX/GA/ICG nanoparticles could act as an HSP90 protein inhibitor to achieve bidirectional sensitization to chemotherapy and photothermal therapy under 808 nm laser irradiation for the first time, effectively ablating breast cancer cells in vitro. This nanodrug was expected to be used for the efficient treatment of tumors.
RESUMO
As an effective strategy for oncotherapy, developing efficacious drug delivery systems for cancer combination therapy remains a major challenge. To improve nanodrug biocompatibility and composite function facilitating their clinical conversion application, a novel nanocarrier was presented by a facile method through conjugating humic acid with gadolinium ions to synthesize HA-Gd with good biocompatibility and dispersity. HA-Gd exhibited high photothermal conversion efficiency up to 38%, excellent photothermal stability, and high doxorubicin (DOX) loading capacity (93%) with pH-responsive release properties. HA-Gd loading DOX showed a combined chemo-photothermal inhibitory effect on tumor cells. Compared with lipid-DOX, HA-Gd-DOX had a more significant inhibitory effect on tumor growth and fewer side effects. T1-weighted MRI contrast toward tumor tissue provided HA-Gd with an MRI-based cancer diagnosis. This study revealed the great potential of humic acids as a novel vector for developing more drug carriers with desirable functions for clinical anticancer therapy.
RESUMO
Three new abietane-type diterpenoids, named callicapoic acid M3 (1), callicapoic acid M4 (2) and callicapoic acid M5 (3), were isolated from the Callicarpa macrophylla Vahl. Their structures were established by spectroscopic techniques (IR, UV, MS, 1D and 2D NMR). All the isolated three compounds were evaluated for inhibitory activity on NO production in LPS-activated RAW 264.7 macrophage cells by using MTT assays. Compounds 1, 2 and 3 showed potent inhibitory activity, with inhibition rates of 34.47-40.13%.