Efficient gene delivery to human umbilical cord mesenchymal stem cells by cationized Porphyra yezoensis polysaccharide nanoparticles

Photoluminescent Cationic Carbon Dots as efficient Non-Viral Delivery of Plasmid SOX9 and Chondrogenesis of Fibroblasts

With the increasing demand for higher gene carrier performance, a multifunctional vector could immensely simplify gene delivery for disease treatment; nevertheless, the current non- viral vectors lack self-tracking ability. Here, a type of novel, dual-functional cationic carbon dots (CDs), produced through one-step, microwave-assisted pyrolysis of arginine and glucose, have been utilized as both a self-imaging agent and a non-viral gene vector for chondrogenesis from fibroblasts. The cationic CDs could condense the model gene plasmid SOX9 (pSOX9) to form ultra-small (10–30 nm) nanoparticles which possessed several favorable properties, including high solubility, tunable fluorescence, high yield, low cytotoxicity and outstanding biocompatibility. The MTT assay indicated that CDs/pSOX9 nanoparticles had little cytotoxicity against mouse embryonic fibroblasts (MEFs) compared to Lipofectamine2000 and PEI (25 kDa). Importantly, the CDs/pSOX9 nanoparticles with tunable fluorescence not only enabled the intracellular tracking of the nanoparticles, but also could successfully deliver the pSOX9 into MEFs with significantly high efficiency. Furthermore, the CDs/pSOX9 nanoparticles-mediated transfection of MEFs showed obvious chondrogenic differentiation. Altogether, these findings demonstrated that the CDs prepared in this study could serve as a paradigmatic example of the dual-functional reagent for both self-imaging and effective non-viral gene delivery.

Biosynthesis of Au, Ag and Au-Ag bimetallic nanoparticles using protein extracts of Deinococcus radiodurans and evaluation of their cytotoxicity

Background

Biosynthesis of noble metallic nanoparticles (NPs) has attracted significant interest due to their environmental friendly and biocompatible properties.

Methods

In this study, we investigated syntheses of Au, Ag and Au–Ag bimetallic NPs using protein extracts of Deinococcus radiodurans, which demonstrated powerful metal-reducing ability. The obtained NPs were characterized and analyzed by various spectroscopy techniques.

Results

The D. radiodurans protein extract-mediated silver nanoparticles (Drp-AgNPs) were preferably monodispersed and stably distributed compared to D. radiodurans protein extract-mediated gold nanoparticles (Drp-AuNPs). Drp-AgNPs and Drp-AuNPs exhibited spherical morphology with average sizes of 37.13±5.97 nm and 51.72±7.38 nm and zeta potential values of −18.31±1.39 mV and −15.17±1.24 mV at pH 7, respectively. The release efficiencies of Drp-AuNPs and Drp-AgNPs measured at 24 h were 3.99% and 18.20%, respectively. During the synthesis process, Au(III) was reduced to Au(I) and further to Au(0) and Ag(I) was reduced to Ag(0) by interactions with the hydroxyl, amine, carboxyl, phospho or sulfhydryl groups of proteins and subsequently stabilized by these groups. Some characteristics of Drp-AuNPs were different from those of Drp-AgNPs, which could be attributed to the interaction of the NPs with different binding groups of proteins. The Drp-AgNPs could be further formed into Au–Ag bimetallic NPs via galvanic replacement reaction. Drp-AuNPs and Au–Ag bimetallic NPs showed low cytotoxicity against MCF-10A cells due to the lower level of intracellular reactive oxygen species (ROS) generation than that of Drp-AgNPs.

Conclusions

These results are crucial to understand the biosynthetic mechanism and properties of noble metallic NPs using the protein extracts of bacteria. The biocompatible Au or Au–Ag bimetallic NPs are applicable in biosensing, bioimaging and biomedicine.

Direct reprogramming of mouse fibroblasts into neural cells via Porphyra yezoensis polysaccharide based high efficient gene co-delivery

BACKGROUND

The cell source for transplantation therapy is always a prerequisite question to be solved in clinical applications. Neural cells are considered non-regenerable, which highly restrict their application in the treatment for nerve injury. Therefore, neural trans-differentiation based on gene transfection provides a new solution to this issue. Compared to viral strategy, non-viral gene delivery systems are considered as a more promising way to achieve this aim. This study centers on a novel application of Porphyra yezoensis polysaccharide as a non-viral gene carrier for the neural trans-differentiation of mouse fibroblasts.

RESULTS

Ethanediamine modified P. yezoensis polysaccharide (Ed-PYP) served as a gene carrier and a group of plasmids that encode Ascl1, Brn4, and Tcf3 (pABT) self-assembled into nanoparticles. Results demonstrated that Ed-PYP-pABT nanoparticles at Ed-PYP: pABT weight ratio of 40:1 was the optimal candidate for gene delivery. ELISA assay revealed the highest expression levels of NGF, BDNF and SHH at 14 days after last transfection. Immunofluorescence and western blot assays also showed robust expression of neural markers including Nestin, GFAP, β-3tubulin, NF200, GAP43 and MAP2, in induced 3T6 cells at this time point.

CONCLUSION

Overall, these findings indicated that the P. yezoensis polysaccharide-based non-viral gene co-delivery system is a promising strategy for the generation of neural cells, which might facilitate the developments in the recovery of neural injuries.

Cytotoxic effect of zinc oxide nanoparticles on murine photoreceptor cells via potassium channel block and Na+ /K+ -ATPase inhibition

OBJECTIVE

Zinc oxide (ZnO) nanoparticles can exhibit toxicity towards organisms and oxidative stress is often hypothesized to be one of the most important factors. Nevertheless, the detailed mechanism of toxicity-induced by ZnO nanoparticles has not been completely addressed. The present study aimed to investigate the toxic effects of ZnO nanoparticles on the expression and activity of Na⁺ /K⁺ -ATPase and on potassium channel block.

MATERIALS AND METHODS

In the present study, we explored the cytotoxic effect of ZnO nanoparticles on murine photoreceptor cells using lactate dehydrogenase (LDH) release assay, reactive oxygen species (ROS) determination, mitochondrial membrane potential (Δφm) measurement, delayed rectifier potassium current recordings and Na⁺ /K⁺ -ATPase expression and activity monitoring.

RESULTS

The results indicated that ZnO nanoparticles could increase the LDH release in medium, aggravate the ROS level within cells, collapse the Δφm, block the delayed rectifier potassium current, and attenuate the expressions of Na⁺ /K⁺ -ATPase at both mRNA and protein levels and its activity, and thus exert cytotoxic effects on murine photoreceptor cells, finally damaging target cells.

CONCLUSION

Our findings will facilitate the understanding of the mechanism involved in ZnO nanoparticle-induced cytotoxicity in murine photoreceptor cells via potassium channel block and Na⁺ /K⁺ -ATPase inhibition.

Robust aptamer-polydopamine-functionalized M-PLGA-TPGS nanoparticles for targeted delivery of docetaxel and enhanced cervical cancer therapy

One limitation of current biodegradable polymeric nanoparticles (NPs) is the contradiction between functional modification and maintaining formerly excellent bioproperties with simple procedures. Here, we reported a robust aptamer-polydopamine-functionalized mannitol-functionalized poly(lactide-co-glycolide) (M-PLGA)-D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoformulation (Apt-pD-NPs) for the delivery of docetaxel (DTX) with enhanced cervical cancer therapy effects. The novel DTX-loaded Apt-pD-NPs possess satisfactory advantages: 1) increased drug loading content and encapsulation efficiency induced by star-shaped copolymer M-PLGA-TPGS; 2) significant active targeting effect caused by conjugated AS1411 aptamers; and 3) excellent long-term compatibility by incorporation of TPGS. Therefore, with simple preparation procedures and excellent bioproperties, the new functionalized Apt-pD-NPs could maximally increase the local effective drug concentration on tumor sites, achieving enhanced treatment effectiveness and minimizing side effects. In a word, the robust DTX-loaded Apt-pD-NPs could be used as potential nanotherapeutics for cervical cancer treatment, and the aptamer-polydopamine modification strategy could be a promising method for active targeting of cancer therapy with simple procedures.

Pleurotus eryngii Polysaccharide Promotes Pluripotent Reprogramming via Facilitating Epigenetic Modification

Pleurotus eryngii is a medicinal/edible mushroom with great nutritional value and bioactivity. Its polysaccharide has recently been developed into an effective gene vector via cationic modification. In the present study, cationized P. eryngii polysaccharide (CPS), hybridized with calcium phosphate (CP), was used to codeliver plasmids (Oct4, Sox2, Klf4, c-Myc) for generating induced pluripotent stem cells (iPSCs). The results revealed that the hybrid nanoparticles could significantly enhance the process and efficiency of reprogramming (1.6-fold increase) compared with the CP nanoparticles. The hybrid CPS also facilitated epigenetic modification during the reprogramming. Moreover, these hybrid nanoparticles exhibited multiple pathways (both caveolae- and clathrin-mediated endocytosis) in their cellular internalization, which accounted for the improved iPSCs generation. These findings therefore present a novel application of P. eryngii polysaccharide in pluripotent reprogramming via active epigenetic modification.