Strategies for surface modification of gelatin-based nanoparticles.

Recently developed methodologies related to surface modification of nanoparticles provide nano systems with the final properties required for a desired application. In nano-pharmaceutical field, the major goals of surface modification are to make nanoparticles unrecognizable by the immune system and to guide them to the desired site. Such a modification can be accomplished through functionalization of NPs by conjugating or coating a molecule whose properties alter nanoparticle surface characteristics. In his regard, gelatin-based nanoparticles (GNPs) have shown great potential as multifunctional drug delivery systems because they could be easily tailored by including targeting moieties, hydrophilic polymers, fluorescence dyes, or different therapeutic agents without the loss of their desired physical, chemical, and biological properties. Research on GNPs for drug and gene delivery has been increasing dramatically over the last decade due to their special features such as good biocompatibility, biodegradability, and low immunogenicity. This review provides an overview of the ongoing research in the field of recent advances in the functionalization of gelatin based NPs for pharmaceutical and medical applications.

Survival Improvement in Human Retinal Pigment Epithelial Cells via Fas Receptor Targeting by miR-374a.

Oxidative conditions of the eye could contribute to retinal cells loss through activating the Fas-L/Fas pathway. This phenomenon is one of the leading causes of some ocular diseases like age-related macular degeneration (AMD). By targeting proteins at their mRNA level, microRNAs (miRNAs) can regulate gene expression and cell function. The aim of the present study is to investigate Fas targeting by miR-374a and find whether it can inhibit Fas-mediated apoptosis in primary human retinal pigment epithelial (RPE) cells under oxidative stress. So, the primary human RPE cells were transfected with pre-miR-374a pLEX construct using polymeric carrier and were exposed to H2 O2 (200 µM) as an oxidant agent for induction of Fas expression. Fas expression at mRNA and protein level was evaluated by quantitative real-time PCR and Western blot analysis, respectively. These results revealed that miR-374a could prevent Fas upregulation under oxidative conditions. Moreover, Luciferase activity assay confirmed that Fas could be a direct target of miR-374a. The cell viability studies demonstrated that caspase-3 activity was negligible in miR-374a treated cells compared to the controls. Our data suggest miR-374a is a negative regulator of Fas death receptor which is able to enhance the cell survival and protect RPE cells against oxidative conditions. J. Cell. Biochem. 118: 4854-4861, 2017. © 2017 Wiley Periodicals, Inc.