Therapeutic Peptides Are Preferentially Solubilized in Specific Microenvironments within PEG-PLGA Polymer Nanoparticles.

Polymeric nanoparticles are a highly promising drug delivery formulation. However, a lack of understanding of the molecular mechanisms that underlie their drug solubilization and controlled release capabilities has hindered the efficient clinical translation of such technologies. Polyethylene glycol-poly(lactic-co-glycolic) acid (PEG-PLGA) nanoparticles have been widely studied as cancer drug delivery vehicles. In this letter, we use unbiased coarse-grained molecular dynamics simulations to model the self-assembly of a PEG-PLGA nanoparticle and its solubulization of the anticancer peptide, EEK, with good agreement with previously reported experimental structural data. We applied unsupervised machine learning techniques to quantify the conformations that polymers adopt at various locations within the nanoparticle. We find that the local microenvironments formed by the various polymer conformations promote preferential EEK solubilization within specific regions of the NP. This demonstrates that these microenvironments are key in controlling drug storage locations within nanoparticles, supporting the rational design of nanoparticles for therapeutic applications.

The menace of severe adverse events and deaths associated with viral gene therapy and its potential solution.

Over the past decade, in vivo gene replacement therapy has significantly advanced, resulting in market approval of numerous therapeutics predominantly relying on adeno-associated viral vectors (AAV). While viral vectors have undeniably addressed several critical healthcare challenges, their clinical application has unveiled a range of limitations and safety concerns. This review highlights the emerging challenges in the field of gene therapy. At first, we discuss both the role of biological barriers in viral gene therapy with a focus on AAVs, and review current landscape of in vivo human gene therapy. We delineate advantages and disadvantages of AAVs as gene delivery vehicles, mostly from the safety perspective (hepatotoxicity, cardiotoxicity, neurotoxicity, inflammatory responses etc.), and outline the mechanisms of adverse events in response to AAV. Contribution of every aspect of AAV vectors (genomic structure, capsid proteins) and host responses to injected AAV is considered and substantiated by basic, translational and clinical studies. The updated evaluation of recent AAV clinical trials and current medical experience clearly shows the risks of AAVs that sometimes overshadow the hopes for curing a hereditary disease. At last, a set of established and new molecular and nanotechnology tools and approaches are provided as potential solutions for mitigating or eliminating side effects. The increasing number of severe adverse reactions and, sadly deaths, demands decisive actions to resolve the issue of immune responses and extremely high doses of viral vectors used for gene therapy. In response to these challenges, various strategies are under development, including approaches aimed at augmenting characteristics of viral vectors and others focused on creating secure and efficacious non-viral vectors. This comprehensive review offers an overarching perspective on the present state of gene therapy utilizing both viral and non-viral vectors.

Zap the clap with DNA: a novel microbicide for preventing Neisseria gonorrhoeae infection.

Each year, Neisseria gonorrhoeae (Ngo) causes over 1.5 million new infections in the United States, and >87 million worldwide. The absence of a vaccine for preventing gonorrhea, the rapid emergence of multidrug-resistant and extremely drug-resistant Ngo strains, and the limited number of antibiotics available for treating gonorrhea underscore the importance of developing new modalities for addressing Ngo infection. Here, we describe DNA-based microbicides that kill Ngo but not commensals. Previously, we showed that Ngo is killed when it takes up differentially methylated DNA with homology to its genome. We exploited this Achilles heel to develop a new class of microbicides for preventing Ngo infection. These microbicides consist of DNA molecules with specific sequences and a methylation pattern different from Ngo DNA. These DNAs kill low-passage and antibiotic-resistant clinical isolates with high efficiency but leave commensals unharmed. Equally important, the DNAs are equally effective against Ngo whether they are in buffered media or personal lubricants. These findings illustrate the potential of this new class of practical, low-cost, self-administered DNA-based microbicides for preventing Ngo transmission during sexual intercourse.

Trends in the synthetic polymer delivery of RNA.

Ribonucleic acid (RNA) has emerged as one of the most promising therapeutic payloads in the field of gene therapy. There are many unique types of RNA that allow for a range of applications including vaccination, protein replacement therapy, autoimmune disease treatment, gene knockdown and gene editing. However, RNA triggers the host immune system, is vulnerable to degradation and has a low proclivity to enter cells spontaneously. Therefore, a delivery vehicle is required to facilitate the protection and uptake of RNA therapeutics into the desired host cells. Lipid nanoparticles have emerged as one of the only clinically approved vehicles for genetic payloads, including in the COVID-19 messenger RNA vaccines. While lipid nanoparticles have distinct advantages, they also have drawbacks, including strong immune stimulation, complex manufacturing and formulation heterogeneity. In contrast, synthetic polymers are a widely studied group of gene delivery vehicles and boast distinct advantages, including biocompatibility, tunability, inexpensiveness, simple formulation and ease of modification. Some classes of polymers enhance efficient transfection efficiency, and lead to lower stimulation of the host immune system, making them more viable candidates for non-vaccine-related applications of RNA medicines. This review aims to identify the most promising classes of synthetic polymers, summarize recent research aimed at moving them into the clinic and postulate the future steps required for unlocking their full potential.

Enhanced Efficacy against Drug-Resistant Tumors Enabled by Redox-Responsive Mesoporous-Silica-Nanoparticle-Supported Lipid Bilayers as Targeted Delivery Vehicles.

Multidrug resistance (MDR) is frequently induced after long-term exposure to reduce the therapeutic effect of chemotherapeutic drugs, which is always associated with the overexpression of efflux proteins, such as P-glycoprotein (P-gp). Nano-delivery technology can be used as an efficient strategy to overcome tumor MDR. In this study, mesoporous silica nanoparticles (MSNs) were synthesized and linked with a disulfide bond and then coated with lipid bilayers. The functionalized shell/core delivery systems (HT-LMSNs-SS@DOX) were developed by loading drugs inside the pores of MSNs and conjugating with D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and hyaluronic acid (HA) on the outer lipid surface. HT-LMSNs-SS and other carriers were characterized and assessed in terms of various characteristics. HT-LMSNs-SS@DOX exhibited a dual pH/reduction responsive drug release. The results also showed that modified LMSNs had good dispersity, biocompatibility, and drug-loading capacity. In vitro experiment results demonstrated that HT-LMSNs-SS were internalized by cells and mainly by clathrin-mediated endocytosis, with higher uptake efficiency than other carriers. Furthermore, HT-LMSNs-SS@DOX could effectively inhibit the expression of P-gp, increase the apoptosis ratios of MCF-7/ADR cells, and arrest cell cycle at the G0/G1 phase, with enhanced ability to induce excessive reactive oxygen species (ROS) production in cells. In tumor-bearing model mice, HT-LMSNs-SS@DOX similarly exhibited the highest inhibition activity against tumor growth, with good biosafety, among all of the treatment groups. Therefore, the nano-delivery systems developed herein achieve enhanced efficacy towards resistant tumors through targeted delivery and redox-responsive drug release, with broad application prospects.

Extracellular vesicles in cancer therapy.

Extracellular vesicles (EVs), including a variety of membrane-enclosed nanosized particles carrying cell-derived cargo, mediate a major type of intercellular communication in physiological and pathological processes. Both cancer and non-cancer cells secrete EVs, which can travel to and influence various types of cells at the primary tumor site as well as in distant organs. Tumor-derived EVs contribute to cancer cell plasticity and resistance to therapy, adaptation of tumor microenvironment, local and systemic vascular remodeling, immunomodulation, and establishment of pre-metastatic niches. Therefore, targeting the production, uptake, and function of tumor-derived EVs has emerged as a new strategy for stand-alone or combinational therapy of cancer. On the other hand, as EV cargo partially reflects the genetic makeup and phenotypic properties of the secreting cell, EV-based biomarkers that can be detected in biofluids are being developed for cancer diagnosis and for predicting and monitoring tumor response to therapy. Meanwhile, EVs from presumably safe sources are being developed as delivery vehicles for anticancer therapeutic agents and as anticancer vaccines. Numerous reviews have discussed the biogenesis and characteristics of EVs and their functions in cancer. Here, I highlight recent advancements in translation of EV research outcome towards improved care of cancer, including developments of non-invasive EV-based biomarkers and therapeutic agents targeting tumor-derived EVs as well as engineering of therapeutic EVs.

Structure-Property Relationships Governing Membrane-Penetrating Behaviour of Complex Coacervates.

Complex coacervates are phase-separated liquid droplets composed of oppositely charged multivalent molecules. The unique material properties of the complex coacervate interior favours the sequestration of biomolecules and facilitates reactions. Recently, it is shown that coacervates can be used for direct cytosolic delivery of sequestered biomolecules in living cells. Here, it is studied that the physical properties required for complex coacervates composed of oligo-arginine and RNA to cross phospholipid bilayers and enter liposomes penetration depends on two main parameters: the difference in ζ-potential between the complex coacervates and the liposomes, and the partitioning coefficient (Kp ) of lipids into the complex coacervates. Following these guidelines, a range of complex coacervates is found that is able to penetrate the membrane of living cells, thus paving the way for further development of coacervates as delivery vehicles of therapeutic agents.

Potential in exosome-based targeted nano-drugs and delivery vehicles for posterior ocular disease treatment: from barriers to therapeutic application.

Posterior ocular disease, a disease that accounts for 55% of all ocular diseases, can contribute to permanent vision loss if left without treatment. Due to the special structure of the eye, various obstacles make it difficult for drugs to reach lesions in the posterior ocular segment. Therefore, the development of highly permeable targeted drugs and delivery systems is particularly important. Exosomes are a class of extracellular vesicles at 30-150 nm, which are secreted by various cells, tissues, and body fluids. They carry various signaling molecules, thus endowing them with certain physiological functions. In this review, we describe the ocular barriers and the biogenesis, isolation, and engineering of exosomes, as exosomes not only have pharmacological effects but also are good nanocarriers with targeted properties. Moreover, their biocompatibility and immunogenicity are better than synthetic nanocarriers. Most importantly, they may have the ability to pass through the blood-eye barrier. Thus, they may be developed as both targeted nano-drugs and nano-delivery vehicles for the treatment of posterior ocular diseases. We focus on the current status and potential application of exosomes as targeted nano-drugs and nano-delivery vehicles in posterior ocular diseases.

Cell-Penetrating Peptides as Vehicles for Delivery of Therapeutic Nucleic Acids. Mechanisms and Application in Medicine.

Currently, nucleic acid therapeutics are actively developed for the treatment and prophylactic of metabolic disorders and oncological, inflammatory, and infectious diseases. A growing number of approved nucleic acid-based drugs evidences a high potential of gene therapy in medicine. Therapeutic nucleic acids act in the cytoplasm, which makes the plasma membrane the main barrier for the penetration of nucleic acid-based drugs into the cell and requires development of special vehicles for their intracellular delivery. The optimal carrier should not only facilitate internalization of nucleic acids, but also exhibit no toxic effects, ensure stabilization of the cargo molecules, and be suitable for a large-scale and low-cost production. Cell-penetrating peptides (CPPs), which match all these requirements, were found to be efficient and low-toxic carriers of nucleic acids. CPPs are typically basic peptides with a positive charge at physiological pH that can form nanostructures with negatively charged nucleic acids. The prospects of CPPs as vehicles for the delivery of therapeutic nucleic acids have been demonstrated in numerous preclinical studies. Some CPP-based drugs had successfully passed clinical trials and were implemented into medical practice. In this review, we described different types of therapeutic nucleic acids and summarized the data on the use of CPPs for their intracellular delivery, as well as discussed, the mechanisms of CPP uptake by the cells, as understanding of these mechanisms can significantly accelerate the development of new gene therapy approaches.

Customer perception and acceptance of autonomous delivery vehicles in the State of Kuwait during COVID-19.

COVID-19 is one of the most important dilemmas that took place during the last few years. Logisticians worked hard to present a new mechanism called Autonomous Delivery Vehicles (ADVs) by which they afford help making life easier for people during pandemic while trying to reduce pollution on road as well. This work mainly aimed to explore Unified Theory of Acceptance and Use of Technology (UTAUT2) and the convenience of users - according to gender - to the idea of using Autonomous Delivery Vehicles (ADVs). A survey-based method was applied and presented. It was distributed online where a total of 450 participants had taken part to express their ideas. Structural Equation Modeling (SEM) was used to analyze the data and the results were discussed thoroughly. The model was conducted according to nine hypotheses. Results showed that all of them were supported except hypothesis 7, which is the trust in technology that negatively influenced the perceived risk leading to rejecting the hypothesis that supposes the validity of H7. It was concluded that the perceived risk and behavioral intention relationship were only significant for males while the perceived risk and trust in technology relationship were only significant for females.

Shedding Light on DNA-Based Nanoprobes for Live-Cell MicroRNA Imaging.

DNA-based nanoprobes integrated with various imaging signals have been employed for fabricating versatile biosensor platforms for the study of intracellular biological process and biomarker detection. The nanoprobes developments also provide opportunities for endogenous microRNA (miRNA) in situ analysis. In this review, the authors are primarily interested in various DNA-based nanoprobes for miRNA biosensors and declare strategies to reveal how to customize the desired nanoplatforms. Initially, various delivery vehicles for nanoprobe architectures transmembrane transport are delineated, and their biosecurity and ability for resisting the complex cellular environment are evaluated. Then, the novel strategies for designing DNA sequences as target miRNA specific recognition and signal amplification modules for miRNA detection are presented. Afterward, recent advances in imaging technologies to accurately respond and produce significant signal output are summarized. Finally, the challenges and future directions in the field are discussed.

Delivery of Small Molecules by Syndiotactic Peptides for Breast Cancer Therapy.

The utilization of peptide-based drug delivery systems has been suboptimal due to their poor proteolytic susceptibility, poor cell permeability, and limited tumor homing capabilities. Earlier attempts in using d-enantiomers in peptide sequences increased proteolytic stability but have compromised the overall penetration capability. We designed a series of peptides (STRAPs) with a syndiotactic polypeptide backbone that can potentially form a spatial array of cationic groups, an important feature that facilitates cellular uptake. The peptides penetrate cell membranes through a combination of active and passive modes. Furthermore, the cellular uptake of the peptides was unaffected by the presence of or treatment with bovine serum and human plasma. The designed peptides successfully delivered methotrexate, an anticancer drug, to the in vitro and in vivo models of breast cancer, with the best performing peptide STRAP-4-MTX conjugate having an EC50 value of 1.34 µM. Peptide drug delivery in mouse xenograft models showed a greater reduction of primary tumor and metastasis of breast cancer, in comparison to methotrexate of the same dose. The in vivo biodistribution assay of the STRAP-4 peptide suggests that the peptide accumulates at the tumor site after 2 h of treatment, and in the absence of tumors, the peptide gets metabolized and excreted from the system.

Research Progress on Bacterial Membrane Vesicles and Antibiotic Resistance.

As a result of antibiotic overuse, bacterial antibiotic resistance has become a severe threat to worldwide public health. The development of more effective antimicrobial therapies and alternative antibiotic strategies is urgently required. The role played by bacterial membrane vesicles (BMVs) in antibiotic resistance has become a current focus of research. BMVs are nanoparticles derived from the membrane components of Gram-negative and Gram-positive bacteria and contain diverse components originating from the cell envelope and cytoplasm. Antibiotic stress stimulates the secretion of BMVs. BMVs promote and mediate antibiotic resistance by multiple mechanisms. BMVs have been investigated as conceptually new antibiotics and drug-delivery vehicles. In this article, we outline the research related to BMVs and antibiotic resistance as a reference for the intentional use of BMVs to combat antibiotic resistance.

The Impact of Lipid Digestion on the Dynamic and Structural Properties of Micelles.

Self-assembled, lipid-based micelles, such as those formed by the short-chain phosphocholine, dihexanoylphosphatidylcholine (2C6PC), are degraded by the pancreatic enzyme, phospholipase A2 (PLA2). Degradation yields 1-hexanoyl-lysophosphocholine (C6LYSO) and hexanoic acid (C6FA) products. However, little is known about the behavior of these products during and after the degradation of 2C6PC. In this work, a combination of static and time-resolved small angle neutron scattering, as well as all-atom molecular dynamics simulations, is used to characterize the structure of 2C6PC micelles. In doing so a detailed understanding of the substrate and product aggregation behavior before, during and after degradation is gained. Consequently, the formation of mixed micelles containing 2C6PC, C6LYSO and C6FA is shown at every stage of the degradation process, as well as the formation of mixed C6LYSO/C6FA micelles after degradation is complete. The use of atomistic molecular dynamics has allowed us to characterize the structure of 2C6PC, 2C6PC/C6LYSO/C6FA, and C6LYSO/C6FA micelles throughout the degradation process, showing the localization of the different molecular species within the aggregates. In addition, the hydration of the 2C6PC, C6LYSO, and C6FA species both during micellization and as monomers in aqueous solution is documented to reveal the processes driving their micellization.

Comprehensive overview of extracellular vesicle proteomics in meningioma: future strategy.

BACKGROUND: Meningioma arising from meninges is one among the various types of brain tumors. Others are, astrocytomas originating from astrocyte, oligodendrogliomas originating from oligodendrocyte, Ependymomas originating from ependymal cells and medulloblastomas originating from neurons. Current knowledge of molecular biology, genetics and epigenetics of meningioma is not sufficient. Therefore, In depth understanding of the mechanism of meningioma formation and progression is needed for its treatment and management. Grade I Grade I meningiomas are majorly classified as grade I, grade II and grade III. Meningioma can be indolent, slow growing or can be invasive and metastatic which can recurre. Grade I meningioma can be removed by surgery in comparison to invasive meningioma which may recurre with high propensity. This property of recurrence is responsible for high morbidity and mortality. Meningioma are majorly classified into three classes namely grade I, grade II, grade III. Protein biomarkers are considered as promising candidates for the diagnosis of meningioma. STUDY: Various studies done on differential expression of proteins have shown increased expression of EGFR, NEK9, EPS812, CKAP4, SET and STAT2, in all the three grades of meningioma. Additionally, some proteins like HK2 are overexpressed in grade II and grade III meningioma than in grade I meningioma. Protein Markers, found on extracellular vesicles of different grades of meningioma can serve the same purpose. A test done on a sample of any kind of body fluid like blood, tear, saliva, urine etc. for recognizing the circulating cancer cells or DNA and extracellular vesicles released from them to help detecting the early stage of cancer is known as liquid biopsy. Solid biopsy has several limitations as compared to liquid biopsy. This is because the samples can be easily collected and studied in case of liquid biopsy. Exosomes are related with liquid biopsy and hence provide platform for better diagnosis, prognosis and treatment of any type of cancer including meningioma. Exosomal tetraspanin are important example of exosomal biomarkers. The tetraspanin network is a molecular scaffold which connects various proteins for signal transduction. CONCLUSION: This study tells about the utility of proper knowledge of extracellular vesicle proteins and their profiles in different grades, which can help in better understanding of pathogenesis, diagnosis, prognosis and treatment of meningioma. In Addition to use of these proteins as biomarkers, role of exosomes in currently available therapeutic approaches has been discussed.

ncRNAs in Therapeutics: Challenges and Limitations in Nucleic Acid-Based Drug Delivery.

Non-coding RNAs (ncRNAs) are emerging therapeutic tools but there are barriers to their translation to clinical practice. Key issues concern the specificity of the targets, the delivery of the molecules, and their stability, while avoiding "on-target" and "off-target" side effects. In this "ncRNA in therapeutics" issue, we collect several studies of the differential expression of ncRNAs in cardiovascular diseases, bone metabolism-related disorders, neurology, and oncology, and their potential to be used as biomarkers or therapeutic targets. Moreover, we review recent advances in the use of antisense ncRNAs in targeted therapies with a particular emphasis on their basic biological mechanisms, their translational potential, and future trends.

Extracellular Vesicles from Plants: Current Knowledge and Open Questions.

The scientific interest in the beneficial properties of natural substances has been recognized for decades, as well as the growing attention in extracellular vesicles (EVs) released by different organisms, in particular from animal cells. However, there is increasing interest in the isolation and biological and functional characterization of these lipoproteic structures in the plant kingdom. Similar to animal vesicles, these plant-derived extracellular vesicles (PDEVs) exhibit a complex content of small RNAs, proteins, lipids, and other metabolites. This sophisticated composition enables PDEVs to be therapeutically attractive. In this review, we report and discuss current knowledge on PDEVs in terms of isolation, characterization of their content, biological properties, and potential use as drug delivery systems. In conclusion, we outline controversial issues on which the scientific community shall focus the attention shortly.

Understanding the Potential of Genome Editing in Parkinson's Disease.

CRISPR is a simple and cost-efficient gene-editing technique that has become increasingly popular over the last decades. Various CRISPR/Cas-based applications have been developed to introduce changes in the genome and alter gene expression in diverse systems and tissues. These novel gene-editing techniques are particularly promising for investigating and treating neurodegenerative diseases, including Parkinson's disease, for which we currently lack efficient disease-modifying treatment options. Gene therapy could thus provide treatment alternatives, revolutionizing our ability to treat this disease. Here, we review our current knowledge on the genetic basis of Parkinson's disease to highlight the main biological pathways that become disrupted in Parkinson's disease and their potential as gene therapy targets. Next, we perform a comprehensive review of novel delivery vehicles available for gene-editing applications, critical for their successful application in both innovative research and potential therapies. Finally, we review the latest developments in CRISPR-based applications and gene therapies to understand and treat Parkinson's disease. We carefully examine their advantages and shortcomings for diverse gene-editing applications in the brain, highlighting promising avenues for future research.

Dendrimers as Non-Viral Vectors in Gene-Directed Enzyme Prodrug Therapy.

Gene-directed enzyme prodrug therapy (GDEPT) has been intensively studied as a promising new strategy of prodrug delivery, with its main advantages being represented by an enhanced efficacy and a reduced off-target toxicity of the active drug. In recent years, numerous therapeutic systems based on GDEPT strategy have entered clinical trials. In order to deliver the desired gene at a specific site of action, this therapeutic approach uses vectors divided in two major categories, viral vectors and non-viral vectors, with the latter being represented by chemical delivery agents. There is considerable interest in the development of non-viral vectors due to their decreased immunogenicity, higher specificity, ease of synthesis and greater flexibility for subsequent modulations. Dendrimers used as delivery vehicles offer many advantages, such as: nanoscale size, precise molecular weight, increased solubility, high load capacity, high bioavailability and low immunogenicity. The aim of the present work was to provide a comprehensive overview of the recent advances regarding the use of dendrimers as non-viral carriers in the GDEPT therapy.

Conformationally constrained peptides for drug delivery.

Peptides have shown great potential in acting as template for developing versatile carrier platforms in nanomedicine, aimed at selective delivery of drugs to only pathological tissues saving its normal neighbors. Cell-penetrating peptides (CPPs) are short oligomeric peptides capable of translocating across the cell membrane while simultaneously employing multiple mechanisms of entry. Most CPPs exist as disordered structures in solution and may adopt a helical conformation on interaction with cell membrane, vital to their penetrative capability. Herein, we report a series of cationic helical amphipathic peptides (CHAPs), which are topologically constrained to be helical. The peptides were tested against cervical and breast cancer cells for their cell penetration and drug delivery potential. The cellular uptake of CHAP peptides is independent of temperature and energy availability. The activity of the peptides is biocompatible in bovine serum. CHAPs delivered functional methotrexate (MTX) inside the cell as CHAP-MTX conjugates. CHAP-MTX conjugates were more toxic to cancer cells than MTX alone. However, the CHAP-MTX conjugates were less toxic to HEK-293 cells compared with the cancer cells suggesting higher affinity towards cancer cells.