All-trans retinoic acid release from surfactant-free nanoparticles of poly(DL-lactide-co-glycolide)

Retinoic acid loaded with chitosan nanoparticles improves spermatogenesis in scrotal hyperthermia in mice

OBJECTIVE

High temperatures can trigger cellular oxidative stress and disrupt spermatogenesis, potentially leading to male infertility. We investigated the effects of retinoic acid (RA), chitosan nanoparticles (CHNPs), and retinoic acid loaded with chitosan nanoparticles (RACHNPs) on spermatogenesis in mice induced by scrotal hyperthermia (Hyp).

METHODS

Thirty mice (weighing 25 to 30 g) were divided into five experimental groups of six mice each. The groups were as follows: control, Hyp induced by a water bath (43 °C for 30 minutes/day for 5 weeks), Hyp+RA (2 mg/kg/day), Hyp+CHNPs (2 mg/kg/72 hours), and Hyp+RACHNPs (4 mg/kg/72 hours). The mice were treated for 35 days. After the experimental treatments, the animals were euthanized. Sperm samples were collected for analysis of sperm parameters, and blood serum was isolated for testosterone measurement. Testis samples were also collected for histopathology assessment, reactive oxygen species (ROS) evaluation, and RNA extraction, which was done to compare the expression levels of the bax, bcl2, p53, Fas, and FasL genes among groups. Additionally, immunohistochemical staining was performed.

RESULTS

Treatment with RACHNPs significantly increased stereological parameters such as testicular volume, seminiferous tubule length, and testicular cell count. Additionally, it increased testosterone concentration and improved sperm parameters. We observed significant decreases in ROS production and caspase-3 immunostaining in the RACHNP group. Moreover, the expression levels of bax, p53, Fas, and FasL significantly decreased in the groups treated with RACHNPs and RA.

CONCLUSION

RACHNPs can be considered a potent antioxidative and antiapoptotic agent for therapeutic strategies in reproductive and regenerative medicine.

Exploiting the Lymph-Node-Amplifying Effect for Potent Systemic and Gastrointestinal Immune Responses via Polymer/Lipid Nanoparticles

Parenteral vaccinations are not able to elicit effective systemic and gastrointestinal immune protection simultaneously because the lymphocytes are typically restricted to primed tissues. Although all-trans retinoic acid (atRA) was reported to trigger the gut-homing of immunocytes, the bioavailability and systemic immune responses remain limited for use in robust enteric vaccinations. Here, we show that co-delivery of atRA, CpG oligodeoxynucleotides (CpG), and antigens via engineered polymer/lipid nanoparticles (PLNPs) could exploit the amplifying function of draining lymph nodes (DLNs) for potent gut tropism and immune activations. After intramuscular injection, forming an immune-potentiated environment at the injection site, the PLNPs induced the designated transfer of primed dendritic cells (DCs) to the DLNs instead of the gastrointestinal tissues. Within the DLNs, the immune-potentiated environment markedly amplified the antigen presentation and homing receptor switch among immunocytes, which simultaneously stimulated the preferential dissipation of activated lymphocytes in the peripheral and gastrointestinal tissues, that is, exerted a DLN-amplifying effect. Compared with current atRA-containing formulations, the PLNPs not only boosted potent IgG secretions and T cell activations in the peripheral tissue but also provoked robust T cell homing and antigen-specific IgA levels in the gastrointestinal tracts in both ovalbumin and EV71 vaccinations. These data indicate that exploiting DLN amplification can stimulate potent systemic and gastrointestinal responses for more efficient enteric vaccinations.

Tailored release of triiodothyronine and retinoic acid from a spatio-temporally fabricated nanofiber composite instigating neuronal differentiation

Regeneration of the central and peripheral nervous system is challenging since the functional restoration of injured nerves is an incredible task. The fabrication of an ideal nerve guide that fulfills the requirement to regenerate nerve tissue is a herculean challenge requiring a combination of both biochemical and topographical cues. The present study explores the combinatorial effect of aligned nanofibers and the regulated delivery of triiodothyronine and retinoic acid on nerve regeneration. A sequential release mechanism is adopted in fabricating the nanofiber scaffold, with triiodothyronine incorporated into the nanofiber shell ensuring its prior release, followed by retinoic acid (entrapped within zein nanoparticles) from the core. The composite nanofibers thus fabricated possess excellent mechanical, physical and thermal properties and good topographical morphology and were highly biocompatible. The nanofibers were scrutinized for their efficacy in stimulating differentiation to a neuronal phenotype. The elongation factor (E-factor) of the neural cells had doubled in the bioactive incorporated composite compared to other scaffolds, as observed on phalloidin staining of their cytoskeleton, which endorsed enhanced neural differentiation on the fabricated nanofiber scaffold. There was a significant increase in the expression of neural-lineage specific markers on investigation of mRNA by real time PCR, showing a 10 fold increase in the gene expression of β-III-tubulin, a 5.5 fold increase for microtubule associated protein 2 gene and 3.5 fold for neurofilament M gene in the cells cultured over bioactive incorporated aligned nanofiber composites. Similarly protein expression was analyzed by immunofluorescence and flow cytometry studies, which showed an increase in the expression of β-III-tubulin in the composite nanofiber. This corroborates that neuronal differentiation is enhanced by the aligned nanotopography and spatio-temporal delivery of triiodothyronine and retinoic acid, opening avenues for nerve regenerative graft fabrication.

RGD peptide targeted lipid-coated nanoparticles for combinatorial delivery of sorafenib and quercetin against hepatocellular carcinoma

CONTEXT

Combination therapies provide a potential solution to address the tumor heterogeneity and drug resistance issues by taking advantage of distinct mechanisms of action of the multiple therapeutics.

OBJECTIVE

To design arginine-glycineaspartic acid (RGD) modified lipid-coated nanoparticles (NPs) for the co-delivery of the hydrophobic drugs against hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

RGD modified lipid-coated PLGA NPs were developed for the targeted delivery of both sorafenib (SRF) and quercetin (QT) (RGD-SRF-QT NPs). Chemical-physical characteristics and release profiles were evaluated. In vitro cell viability assays were carried out on HCC cells. In vivo antitumor efficacies were evaluated in HCC animal model.

RESULTS AND DISCUSSION

The combination of SRF and QT formulations was more effective than the single drug formulations in both NPs and solution groups. RGD-SRF-QT NPs achieved the most significant tumor growth inhibition effect in vitro and in vivo.

CONCLUSION

The resulting NPs could provide a promising platform for co-delivery of multiple anticancer drugs for achievement of combinational therapy and could offer potential for enhancing the therapeutic efficacy on HCC.

Antitumor activity of sorafenib-incorporated nanoparticles of dextran/poly(dl-lactide-co-glycolide) block copolymer

Sorafenib-incoporated nanoparticles were prepared using a block copolymer that is composed of dextran and poly(DL-lactide-co-glycolide) [DexbLG] for antitumor drug delivery. Sorafenib-incorporated nanoparticles were prepared by a nanoprecipitation-dialysis method. Sorafenib-incorporated DexbLG nanoparticles were uniformly distributed in an aqueous solution regardless of the content of sorafenib. Transmission electron microscopy of the sorafenib-incorporated DexbLG nanoparticles revealed a spherical shape with a diameter < 300 nm. Sorafenib-incorporated DexbLG nanoparticles at a polymer/drug weight ratio of 40:5 showed a relatively uniform size and morphology. Higher initial drug feeding was associated with increased drug content in nanoparticles and in nanoparticle size. A drug release study revealed a decreased drug release rate with increasing drug content. In an in vitro anti-proliferation assay using human cholangiocarcinoma cells, sorafenib-incorporated DexbLG nanoparticles showed a similar antitumor activity as sorafenib. Sorafenib-incorporated DexbLG nanoparticles are promising candidates as vehicles for antitumor drug targeting.