Validation of Smart Nanoparticles as Controlled Drug Delivery Systems: Loading and pH-Dependent Release of Pilocarpine

Research progress of nano delivery systems for intraocular pressure lowering drugs

Glaucoma is a chronic ocular disease characterized by optic atrophy and visual field defect. The main risk factor for glaucoma onset and progression is elevated intraocular pressure, which is caused by increased aqueous humor outflow resistance. Currently, the primary method for glaucoma therapy is the use of intraocular pressure lowering drugs. However, these drugs, when administered through eye drops, have low bioavailability, require frequent administration, and often result in adverse effects. To overcome these challenges, the application of nanotechnology for drug delivery has emerged as a promising approach. Nanoparticles can physically adsorb, encapsulate, or chemically graft drugs, thereby improving their efficacy, retention time, and reducing adverse reactions. Moreover, nanotechnology has opened up new avenues for ocular administration. This article provides a comprehensive review of nano systems for intraocular pressure lowering drugs, encompassing cholinergic agonists, β-adrenergic antagonists, α-adrenergic agonists, prostaglandin analogs, carbonic anhydrase inhibitors, Rho kinase inhibitors, and complex preparations. The aim is to offer novel insights for the development of nanotechnology in the field of intraocular pressure lowering drugs.

Applications of Biomolecular Nanostructures for Anti-Angiogenic Theranostics

Angiogenesis is a physiological process of forming new blood vessels that has pathological importance in seemingly unrelated illnesses like cancer, diabetes, and various inflammatory diseases. Treatment targeting angiogenesis has shown promise for these types of diseases, but current anti-angiogenic agents have critical limitations in delivery and side-effects. This necessitates exploration of alternative approaches like biomolecule-based drugs. Proteins, lipids, and oligonucleotides have recently become popular in biomedicine, specifically as biocompatible components of therapeutic drugs. Their excellent bioavailability and potential bioactive and immunogenic properties make them prime candidates for drug discovery or drug delivery systems. Lipid-based liposomes have become standard vehicles for targeted nanoparticle (NP) delivery, while protein and nucleotide NPs show promise for environment-sensitive delivery as smart NPs. Their therapeutic applications have initially been hampered by short circulation times and difficulty of fabrication but recent developments in nanofabrication and NP engineering have found ways to circumvent these disadvantages, vastly improving the practicality of biomolecular NPs. In this review, we are going to briefly discuss how biomolecule-based NPs have improved anti-angiogenesis-based therapy.

New investigation of anti-inflammatory activity of Polycladia crinita and biosynthesized selenium nanoparticles: isolation and characterization

BACKGROUND

Marine macroalgae have gained interest recently, mostly due to their bioactive components. Polycladia crinita is an example of marine macroalgae from the Phaeophyceae class, also known as brown algae. They are characterized by a variety of bioactive compounds with valuable medical applications. The prevalence of such naturally active marine resources has made macroalgae-mediated manufacturing of nanoparticles an appealing strategy. In the present study, we aimed to evaluate the antioxidant and anti-inflammatory features of an aqueous extract of Polycladia crinita and biosynthesized P. crinita selenium nanoparticles (PCSeNPs) via a carrageenan-induced rat paw edema model. The synthesized PCSeNPs were fully characterized by UV-visible spectroscopy, FTIR, XRD, and EDX analyses.

RESULTS

FTIR analysis of Polycladia crinita extract showed several sharp absorption peaks at 3435.2, 1423.5, and 876.4 cm-1 which represent O-H, C=O and C=C groups. Moreover, the most frequent functional groups identified in P. crinita aqueous extract that are responsible for producing SeNPs are the -NH2-, -C=O-, and -SH- groups. The EDX spectrum analysis revealed that the high percentages of Se and O, 1.09 ± 0.13 and 36.62 ± 0.60%, respectively, confirmed the formation of SeNPs. The percentages of inhibition of the edema in pretreated groups with doses of 25 and 50 mg/kg, i.p., of PCSeNPs were 62.78% and 77.24%, respectively. Furthermore, the pretreated groups with 25, 50 mg/kg of P. crinita extract displayed a substantial decrease in the MDA levels (P < 0.00, 26.9%, and 51.68% decrease, respectively), indicating potent antioxidant effect. Additionally, the pretreated groups with PCSeNPs significantly suppressed the MDA levels (P < 0.00, 54.77%, and 65.08% decreases, respectively). The results of immune-histochemical staining revealed moderate COX-2 and Il-1β expressions with scores 2 and 1 in rats pre-treated with 25 and 50 mg/kg of free extract, respectively. Additionally, the rats pre-treated with different doses of PCSeNPs demonstrated weak COX-2 and Il-1β expressions with score 1 (25 mg/kg) and negative expression with score 0 (50 mg/kg). Both antioxidant and anti-inflammatory effects were dose-dependent.

CONCLUSIONS

These distinguishing features imply that this unique alga is a promising anti-inflammatory agent. Further studies are required to investigate its main active ingredients and possible side effects.

In vitro phototoxicity of zinc phthalocyanine (ZnPc) loaded in liposomes against human breast cancer cells

In this study, zinc phthalocyanine (ZnPc) was encapsulated in liposomes (Phosphatidylcholine (PC) from soybean lecithin (95% phosphatidylcholine, 5% lysophosphatidylcholine), and phosphatidic acid) obtained by a reverse-phase evaporation method. Liposomes were characterized and cytotoxicity and phototoxicity assays were performed using mouse embryo fibroblast (NIH3T3) and human breast cancer (MDAMB231), respectively. ZnPc was successfully encapsulated in liposomes ([Formula: see text]80%), presenting single populations with sizes of [Formula: see text]300 nm and negative zeta potential (-35 to -40 mV). The release profile at different pH presented a biphasic release controlled by the Fickian diffusion mechanism. The cytotoxicity assays carried out on NIH3T3 cells showed that the liposomes provided good protection for ZnPc, and did not affect the viability of non-cancerous cells. In contrast, free ZnPc significantly reduced non-cancerous cell viability at higher concentrations. ZnPc loaded in liposomes ensured a higher phototoxic effect on the MDAMB231 cells at all concentrations tested when exposed to low light dose.

Nanostructured Chitosan-Based Biomaterials for Sustained and Colon-Specific Resveratrol Release

In the present work, we demonstrate the preparation of chitosan-based composites as vehicles of the natural occurring multi-drug resveratrol (RES). Such systems are endowed with potential therapeutic effects on inflammatory bowel diseases (IBD), such as Crohn's disease (CD) and ulcerative colitis, through the sustained colonic release of RES from long-lasting mucoadhesive drug depots. The loading of RES into nanoparticles (NPs) was optimized regarding two independent variables: RES/polymer ratio, and temperature. Twenty experiments were carried out and a Box⁻Behnken experimental design was used to evaluate the significance of these independent variables related to encapsulation efficiency (EE). The enhanced RES EE values were achieved in 24 h at 39 °C and at RES/polymer ratio of 0.75:1 w/w. Sizes and polydispersities of the optimized NPs were studied by dynamic light scattering (DLS). Chitosan (CTS) dispersions containing the RES-loaded NPs were ionically gelled with tricarballylic acid to yield CTS-NPs composites. Macro- and microscopic features (morphology and porosity studied by SEM and spreadability), thermal stability (studied by TGA), and release kinetics of the RES-loaded CTS-NPs were investigated. Release patterns in simulated colon conditions for 48 h displayed significant differences between the NPs (final cumulative drug release: 79⁻81%), and the CTS-NPs composites (29⁻34%).

Experimental model design: exploration and optimization of customized polymerization conditions for the preparation of targeted smart materials by the Diels Alder click reaction

The experimental model design proposed herein has proved to be an indispensable tool to rapidly and easily elucidate the optimal polymerization conditions in the preparation of tailor-made responsive materials for biomedical applications.

Stepwise dual pH and redox-responsive cross-linked polypeptide nanoparticles for enhanced cellular uptake and effective cancer therapy

The systemic toxicity, reduced cellular internalization, and uncontrollable intracellular drug release of smart nanoparticles (NPs) still need to be overcome for effective cancer therapy.

Multifunctional Nanosystem for Targeted and Controlled Delivery of Multiple Chemotherapeutic Agents for the Treatment of Drug-Resistant Breast Cancer

By targeting CD44 receptors, inhibiting multidrug resistance (MDR), controlling drug release, and synergistically inhibiting tumor growth, a multilayered nanosystem was developed to serve as a multifunctional platform for the treatment of drug-resistant breast cancers. The multilayer nanosystem is composed of a poly(lactic-co-glycolic acid) core, a liposome second layer, and a chitosan third layer. The chitosan-multilayered nanoparticles (Ch-MLNPs) can co-deliver three chemotherapeutic agents: doxorubicin (DOX), paclitaxel (PTX), and silybin. The three drugs are released from the multilayered NPs in a controlled and sequential manner upon internalization and localization in the cellular endosomes. The presence of a chitosan layer allows the nanosystem to target a well-characterized MDR breast cancer biomarker, the CD44s receptor. In vitro cytotoxicity study showed that the nanosystem loaded with triple drugs, DOX-PTX-silybin, resulted in better antitumor efficacy than the single-drug or dual-drug nano-formulations. Likely attributed to the MDR-inhibition effect of silybin, the co-delivered DOX and PTX exhibited a better synergistic effect on MDR breast cancer cells than on non-MDR breast cancer cells. The in vivo study also showed that the multilayered nanosystem promoted MDR inhibition and synergy between chemotherapeutic agents, leading to significant tumor reduction in a xenograft animal model. Ch-MLNPs reduced the tumor volume by fivefold compared to that of the control group without causing overt cytotoxicity.