Effects of Chitosan on Loading and Releasing for Doxorubicin Loaded Porous Hydroxyapatite-Gelatin Composite Microspheres.

Porous hydroxyapatite-gelatin (Hap-Gel) composite microspheres derived by wet chemical methods were used as carriers of doxorubicin (DOX) coupled with chitosan (Chi) for treating cancers. Through X-ray diffraction, specific surface area porosimetry, chemisorption analysis and inductively coupled plasma mass spectrometry, the crystalline phase, composition, morphology, and pore distribution of HAp-Gel microspheres were all characterized. HAp nanosized crystals and Gel polymers form porous microspheres after blending and exhibit a specific surface area of 158.64 m2/g, pore sizes from 3 to 150 nm, and pore volumes of 0.4915 cm3/g. These characteristics are suitable for carriers of DOX. Furthermore, by the addition of chitosan during drug loading, its drug-entrapment efficiency increases from 70% to 99% and the release duration increases from a 100% burst within a day to only 45% over half a year since the pores in the composite microspheres provide a shielding effect throughout the degradation period of the chitosan. According to the MTT tests, cell viability of DOX-Chi/HAp-Gel is 57.64% on day 5, similar to the result treated with DOX only. It is concluded that under the protection of pores in the microspheres, the chitosan abundant of hydroxyls combining HAp-Gel and DOX by forming hydrogen bonds indeed enhances the entrapment efficiency, prolongs the releasing period and maintains DOX's ability to perform medicine functions unaffected after loading.

Thioridazine Enhances P62-Mediated Autophagy and Apoptosis Through Wnt/ß-Catenin Signaling Pathway in Glioma Cells.

Thioridazine (THD) is a common phenothiazine antipsychotic drug reported to suppress growth in several types of cancer cells. We previously showed that THD acts as an antiglioblastoma and anticancer stem-like cell agent. However, the signaling pathway underlying autophagy and apoptosis induction remains unclear. THD treatment significantly induced autophagy with upregulated AMPK activity and engendered cell death with increased sub-G1 in glioblastoma multiform (GBM) cell lines. Notably, through whole gene expression screening with THD treatment, frizzled (Fzd) proteins, a family of G-protein-coupled receptors, were found, suggesting the participation of Wnt/ß-catenin signaling. After THD treatment, Fzd-1 and GSK3ß-S9 phosphorylation (inactivated form) was reduced to promote ß-catenin degradation, which attenuated P62 inhibition. The autophagy marker LC3-II markedly increased when P62 was released from ß-catenin inhibition. Additionally, the P62-dependent caspase-8 activation that induced P53-independent apoptosis was confirmed by inhibiting T-cell factor/ß-catenin and autophagy flux. Moreover, treatment with THD combined with temozolomide (TMZ) engendered increased LC3-II expression and caspase-3 activity, indicating promising drug synergism. In conclusion, THD induces autophagy in GBM cells by not only upregulating AMPK activity, but also enhancing P62-mediated autophagy and apoptosis through Wnt/ß-catenin signaling. Therefore, THD is a potential alternative therapeutic agent for drug repositioning in GBM.

Anti-inflammatory effects of Calophyllum inophyllum L. in RAW264.7 cells.

Calophyllum inophyllum L. has been used as folk medicine in the treatment of ocular burn and it has demonstrated potential to be an anti-inflammatory agent. The aim of this study was to explore the anti-inflammatory activities of an acetone extract of C. inophyllum L. leaves (CIL). The CIL extract was tested on lipopolysaccharide (LPS)-induced RAW 264.7 cells to evaluate the effect of CIL extract on the expression of nitric oxide (NO) and inducible nitric oxide synthase (iNOS). Results showed that the CIL extract markedly suppressed the LPS-induced production of nitric oxide, as well as the expression of iNOS, cyclooxygenase (COX)-2 and nuclear factor-kappaB (NF-κB) in a dose-dependent manner. LPS-induced microRNA (miR)-146a expression was inhibited by CIL extract, while miR-155 and miR-424 expression was not affected as demonstrated using quantitative RT-PCR analysis. Taken together, these observations show that CIL extract has anti-inflammatory effect, which extends the potential application for prevention of inflammatory diseases, and its mechanism may be partially associated with blocking COX-2 and iNOS of RAW 264.7 cells.