Enzyme-Responsive Amphiphilic Peptide Nanoparticles for Biocompatible and Efficient Drug Delivery

Self-assembled peptide nanostructures recently have gained much attention as drug delivery systems. As biomolecules, peptides have enhanced biocompatibility and biodegradability compared to polymer-based carriers. We introduce a peptide nanoparticle system containing arginine, histidine, and an enzyme-responsive core of repeating GLFG oligopeptides. GLFG oligopeptides exhibit specific sensitivity towards the enzyme cathepsin B that helps effective controlled release of cargo molecules in the cytoplasm. Arginine can induce cell penetration, and histidine facilitates lysosomal escape by its buffering capacity. Herein, we propose an enzyme-responsive amphiphilic peptide delivery system (Arg-His-(Gly-Phe-Lue-Gly)3, RH-(GFLG)3). The self-assembled RH-(GFLG)3 globular nanoparticle structure exhibited a positive charge and formulation stability for 35 days. Nile Red-tagged RH-(GFLG)3 nanoparticles showed good cellular uptake compared to the non-enzyme-responsive control groups with d-form peptides (LD (LRH-D(GFLG)3), DL (DRH-L(GFLG)3), and DD (DRH-D(GFLG)3). The RH-(GFLG)3 nanoparticles showed negligible cytotoxicity in HeLa cells and human RBCs. To determine the drug delivery efficacy, we introduced the anticancer drug doxorubicin (Dox) in the RH-(GFLG)3 nanoparticle system. LL-Dox exhibited formulation stability, maintaining the physical properties of the nanostructure, as well as a robust anticancer effect in HeLa cells compared to DD-Dox. These results indicate that the enzyme-sensitive RH-(GFLG)3 peptide nanoparticles are promising candidates as drug delivery carriers for biomedical applications.

Engineered Dutasteride-Lipid Based Nanoparticle (DST-LNP) System Using Oleic and Stearic Acid for Topical Delivery

Male pattern baldness (MPB) is a common condition that has a negative impact on the psycho-social health of many men. This study aims to engineer an alcohol-free formulation to cater for individuals who may have had allergic reactions to alcohol-based preparations. A lipid-based nanoparticle system composed of stearic and oleic acid (solid and liquid lipid) was used to deliver dutasteride (DST) for topical application. Two compositions, with oleic acid (Formulation A) and without (Formulation B), were compared to analyse the role of oleic acid as a potential active ingredient in addition to DST. DST-loaded LNP were prepared using the emulsification–ultrasonication method. All of the prepared formulations were spherical in shape in the nanometric size range (150–300 nm), with entrapment efficiencies of >75%. X-ray diffractograms revealed that DST exists in an amorphous form within the NLP matrices. The drug release behaviour from both LNP preparations displayed slow release of DST. Permeation studies through pig ear skin demonstrated that DST-LNP with oleic acid produced significantly lower permeation into the dermis compared to the formulation without oleic acid. These results suggest that the proposed formulation presents several characteristics which are novel, indicating its suitability for the dermal delivery of anti-androgenic molecules.

Improved In Vivo Delivery of Small RNA Based on the Calcium Phosphate Method

In the past few years, we have demonstrated the efficacy of a nanoparticle system, super carbonate apatite (sCA), for the in vivo delivery of siRNA/miRNA. Intravenous injection of sCA loaded with small RNAs results in safe, high tumor delivery in mouse models. To further improve the efficiency of tumor delivery and avoid liver toxicity, we successfully developed an inorganic nanoparticle device (iNaD) via high-frequency ultrasonic pulverization combined with PEG blending during the production of sCA. Compared to sCA loaded with 24 μg of miRNA, systemic administration of iNaD loaded with 0.75 μg of miRNA demonstrated similar delivery efficiency to mouse tumors with little accumulation in the liver. In the mouse therapeutic model, iNaD loaded with 3 μg of the tumor suppressor small RNA MIRTX resulted in an improved anti-tumor effect compared to sCA loaded with 24 μg. Our findings on the bio-distribution and therapeutic effect of iNaD provide new perspectives for future nanomedicine engineering.

Development of Natural Polysaccharide–Based Nanoparticles of Berberine to Enhance Oral Bioavailability: Formulation, Optimization, Ex Vivo, and In Vivo Assessment

The phytogenous alkaloid berberine (BBR) has become a potential drug for the treatment of diabetes, hyperlipidemia, and cancer. However, its therapeutic potential is limited because ofpoor intestinal absorption due to its efflux by the P-gp expressed in the intestinal lumen. Therefore, we aimed to design and fabricate a nanoparticulate system for delivery of BBR employing naturally derived biodegradable and biocompatible polymers, mainly chitosan and alginate, to enhance the oral bioavailability of BBR. A chitosan-alginate nanoparticle system loaded with BBR (BNPs) was formulated by ionic gelation method and was optimized by employing a three-factor, three-level Box-Behnken statistical design. BNPs were characterized for various physicochemical properties, ex vivo, and in vivo evaluations. The optimized BNPs were found to be 202.2 ± 4.9 nm in size, with 0.236 ± 0.02 of polydispersity index, zeta potential -14.8 ± 1.1 mV, and entrapment efficiency of 85.69 ± 2.6%. BNPs showed amorphous nature with no prominent peak in differential scanning calorimetry (DSC) investigation. Similarly, fourier-transform infrared spectroscopy (FTIR) studies did not reveal any interaction between BBR and excipients used. The drug release followed Higuchi kinetics, since these plots demonstrated the highest linearity (R2 = 0.9636), and the mechanism of release was determined to be anomalous or non-Fickian in nature. An ex-vivo gut permeation study showed that BNPs were better internalized into the cells and more highly permeated through the intestine. Furthermore, in vivo pharmacokinetic analysis in female Wistar rats showed a 4.10−fold increase in the oral bioavailability of BBR from BNPs as compared to BBR suspension. With these findings, we have gained new insight into the effective delivery of poorly soluble and permeable drugs via a chitosan-alginate nanoparticle system to improve the therapeutic performance of an oral nanomedicine.

NANOPARTICLE AS THE STRATEGY FOR THE DEVELOPMENT OF SARS-COV-2 ANTIVIRAL DRUGS

In just a matter of months, SARS-CoV-2 had spread around the world. Scientists collaborate to solve the problem. The development of antiviral drugs is a challenge in itself due to the rapidly changing nature of the virus. Selection of drug candidates can be done quickly through the repurposing drug method. Broad-spectrum antiviral drugs may be strong candidates for SARS-CoV-2 therapy. Nanotechnology is one solution in the development of antiviral drug delivery systems. The advantages possessed by the nanoparticle system can answer the need for an ideal antiviral drug. This article will focus on the development of nanoparticle preparations as a strategy in handling viruses, including SARS-CoV-2. The selection of article for the current review was searched from specialized databases such as Elsevier, Pubmed, Science Direct, Medscape and other credible databases using the keywords nanoparticle, SARS-CoV-2, Covid-19, drug repurposing, polymeric nanoparticle, micelle, liposome, solid lipid nanoparticle, nanostructured lipid carrier, dendrimer, metallic nanoparticle. The range of articles was 2007–2021.

A Poly-Chitosan and Cis-Platinum Conjugated Composite Nanoparticle System for Liver Cancer Therapy

The aim of this study was to test an effective nano-pole capsule loaded cis-platinum (CP) transplantation device for liver cancer (LC) therapy. A novel nano-pole capsule was designed as a new vector for storing CP. HepG2 cells and a B6/J mouse model were used to test the efficiency of polyethyleneimine-cis-platinum (PEI-CP) and poly-chitosan-cis-platinum (PC-CP). Infiltration efficiency and transplantation efficiency tests were performed to study the performance of the delivery system, and fibroblast reactions and macrophage numbers were observed, to test for immune rejection and foreign body reactions. The apoptosis rate and tumor diameter of hepatocellular carcinoma cells were used to evaluate the effect of the tumor therapy. We also studied the functional mechanism of different CP delivery systems. The infiltration and transplantation efficiencies of PC-CP were higher than that of PEI-CP; Less foreign body reaction appeared in PC system, with less fibroblast reaction and lower macrophage reaction. The clinical efficacy of PC-CP in terms of tumor apoptosis and diameter reduction was superior to that of PEI-CP. We demonstrated that PC-CP had a more significant alteration effect on mTOR, P-Ak, LC3 and P53. The PC system can better deliver and release drugs than PEI-CP, and may be a better choice for LC therapy in the future.

Obstacles and Recommendations for Clinical Translation of Nanoparticle System-Based Targeted Alpha-Particle Therapy

The rationale for application of nanotechnology in targeted alpha therapy (TAT) is sound. However, the translational strategy requires attention. Formulation of TAT in nanoparticulate drug delivery systems has the potential to resolve many of the issues currently experienced. As α-particle emitters are more cytotoxic compared to beta-minus-emitting agents, the results of poor biodistribution are more dangerous. Formulation in nanotechnology is also suggested to be the ideal solution for containing the recoil daughters emitted by actinium-225, radium-223, and thorium-227. Nanoparticle-based TAT is likely to increase stability, enhance radiation dosimetry profiles, and increase therapeutic efficacy. Unfortunately, nanoparticles have their own unique barriers towards clinical translation. A major obstacle is accumulation in critical organs such as the spleen, liver, and lungs. Furthermore, inflammation, necrosis, reactive oxidative species, and apoptosis are key mechanisms through which nanoparticle-mediated toxicity takes place. It is important at this stage of the technology’s readiness level that focus is shifted to clinical translation. The relative scarcity of α-particle emitters also contributes to slow-moving research in the field of TAT nanotechnology. This review describes approaches and solutions which may overcome obstacles impeding nanoparticle-based TAT and enhance clinical translation. In addition, an in-depth discussion of relevant issues and a view on technical and regulatory barriers are presented.