Differentiation of PC12 cell line into neuron by Valproic acid encapsulated in the stabilized core-shell liposome-chitosan Nano carriers

Chitosan Thermosensitive Hydrogel Based on DNA Damage Repair Inhibition and Mild Photothermal Therapy for Enhanced Antitumor Treatment

The DNA damage repair of tumor cells limits the effect of photothermal therapy (PTT), and high temperatures induced by PTT can damage adjacent normal tissues. To overcome these limitations, we developed a novel composite hydrogel (OLA-Au-Gel) based on chitosan (CS) and β-glycerophosphate (β-GP), which encapsulated olaparib-liposomes (OLA-lips) and CS-capped gold nanoparticles (CS-AuNPs). OLA-Au-Gel achieved the combination of mild PTT (mPTT) by CS-AuNPs and tumor DNA damage repair inhibition by OLA. The hydrogel showed good biocompatibility, injectability, and photothermal response. Under near-infrared laser irradiation, OLA-Au-Gel inhibited the proliferation of tumor cells, induced the generation of reactive oxygen species in vitro, and effectively inhibited the growth of breast tumors in vivo. OLA-Au-Gel shows a promising application prospect for inhibiting tumor development and improving the antitumor effect. Collectively, we propose a novel strategy for enhanced antitumor therapy based on the combination of mPTT and DNA damage repair inhibition.

Encapsulation of Tea Polyphenol in Zein through Complex Coacervation Technique to Control the Release of the Phenolic Compound from Gelatin-Zein Composite Film

Green tea polyphenol (TP) was encapsulated in zein and fabricated into a gelatin-zein composite film by complex coacervation. Transglutaminase (TG) crosslinking was employed to obtain a compact structural orientation of the film to prolong the release of bioactive compounds. The encapsulation efficiency of zein and the TP release rate from the composite film were investigated. The retention rate was over 30% and 80% after film fabrication and storage, respectively. Crosslinking decreased the diffusion coefficient by half, thus improving the release of TP from the film. The antioxidant properties were satisfactory after discharge from the film detected by DPPH/ABTS scavenging. The value of crosslinking degree (~60%) and increased molecular weight of the protein were investigated by SDS-PAGE, indicating the compatibility of TP and TG treatment. According to physicomechanical findings, the TG2TP1 film exhibited the best characteristics. Tensile strength and water solubility properties were ameliorated by the TG treatment of TP-encapsulated films compared to the control film. TG and TP-loaded gelatin-zein composite film had better thermal stability than the control film. Moreover, the TP loading reduced the transparency value and improved the light-barrier properties of the film. The films showed significant antimicrobial activities against two food-borne bacteria, including Staphylococcus aureus BCTC13962 and Escherichia coli BCRC10675. The result obtained shows that the encapsulation of TP and TG treatment may be used to fabricate gelatin-zein composite film with controlled release of phenolic compounds for active packaging applications.

Effects of HDAC inhibitors on neuroblastoma SH-SY5Y cell differentiation into mature neurons via the Wnt signaling pathway

Histone deacetylase (HDAC) inhibitors affect cell homeostasis, gene expression, and cell cycle progression and promote cell terminal differentiation or apoptosis. However, the effect of HDAC inhibition on SH-SY5Y cells, which are neuroblastoma cells capable of differentiating into neurons under specific conditions, such as in the presence of retinoic acid (RA), is unknown. In this study, we hypothesized that HDAC inhibitors induced the neuronal differentiation of SH-SY5Y cells. To test this hypothesis, we used phase contrast microscopy, immunocytochemistry (ICC), qPCR, and western blotting analysis. MS-275 and valproic acid (VPA), two HDAC inhibitors, were selected to evaluate neuronal differentiation. It was confirmed that cells treated with MS-275 or VPA differentiated into mature neurons, which were distinguished by bipolar or multipolar morphologies with elongated branches. In addition, the mRNA expression of neuronal markers (Tuj1 and NEFH) and the oligodendrocyte marker (CNP) was significantly increased with MS-275 or VPA treatment compared to that with RA treatment. In addition, the protein expression of the other neuronal markers, Tuj1 and NeuN, was highly increased with HDAC inhibitor treatments compared to that with RA treatment. Furthermore, we confirmed that noncanonical Wnt signaling was upregulated by HDAC inhibitors via MAPK signaling and the Wnt/JNK pathway. Therefore, both MS-275 and VPA promoted the differentiation of SH-SY5Y cells into mature neurons via the Wnt signaling pathway.

Freeze Drying of Polymer Nanoparticles and Liposomes Exploiting Different Saccharide-Based Approaches

Biodegradable nanocarriers represent promising tools for controlled drug delivery. However, one major drawback related to their use is the long-term stability, which is largely influenced by the presence of water in the formulations, so to solve this problem, freeze-drying with cryoprotectants has been proposed. In the present study, the influence of the freeze-drying procedure on the storage stability of poly(lactide-co-glycolide) (PLGA) nanoparticles and liposomes was evaluated. In particular, conventional cryoprotectants were added to PLGA nanoparticle and liposome formulations in various conditions. Additionally, hyaluronic acid (HA), known for its ability to target the CD44 receptor, was assessed as a cryoprotective excipient: it was added to the nanocarriers as either a free molecule or conjugated to a phospholipid to increase the interaction with the polymer or lipid matrix while exposing HA on the nanocarrier surface. The formulations were resuspended and characterized for size, polydispersity index, zeta potential and morphology. It was demonstrated that only the highest percentages of cryoprotectants allowed the resuspension of stable nanocarriers. Moreover, unlike free HA, HA-phospholipid conjugates were able to maintain the particle mean size after the reconstitution of lyophilized nanoparticles and liposomes. This study paves the way for the use of HA-phospholipids to achieve, at the same time, nanocarrier cryoprotection and active targeting.