Therapeutic Effects in a Transient Middle Cerebral Artery Occlusion Rat Model by Nose-To-Brain Delivery of Anti-TNF-Alpha siRNA with Cell-Penetrating Peptide-Modified Polymer Micelles

Brain targeted polymeric micelles as drug carriers for ischaemic stroke treatment

Ischaemic stroke is a central nervous system disease with high morbidity, recurrence and mortality rates. Thrombolytic and neuroprotective therapies are the main therapeutic strategies for ischaemic stroke, however, the poor delivery efficiency of thrombolytic and neuroprotective drugs to the brain limits their clinical application. So far, the development of nanomedicine has brought opportunities for the above challenges, which can not only realise the effective accumulation of drugs in the target site, but also improve the pharmacokinetic behaviour of the drugs. Among the most rapidly developing nanoparticles, micelles gradually emerging as an effective strategy for ischaemic stroke treatment due to their own unique advantages. This review provided an overview of targeted and response-release micelles based on the physicochemical properties of the ischaemic stroke microenvironment, summarised the targeting strategies for delivering micellar formulations to the thrombus, blood-brain barrier, and brain parenchyma, and finally described the potentials and challenges of polymeric micelles in the treatment of ischaemic stroke.

Therapeutic Efficacy of Intranasal N-Acetyl-L-Cysteine with Cell-Penetrating Peptide-Modified Polymer Micelles on Neuropathic Pain in Partial Sciatic Nerve Ligation Mice

Background/Objectives: We previously demonstrated that the intranasal administration of cell-penetrating Tat peptide-modified carrier, PEG-PCL-Tat, improves drug delivery to the central nervous system. This study aimed to evaluate the potential of the post-onset intranasal administration of N-acetyl-L-cysteine (NAC) combined with PEG-PCL-Tat (NAC/PPT) for neuropathic pain. Methods: Neuropathic pain was induced by partial sciatic nerve ligation (PSNL) in mice. Mechanical allodynia was assessed using the von Frey test on days 11-14 post-ligation. NAC or NAC/PPT was intranasally administered after pain onset. Western blotting and immunohistochemistry were conducted to evaluate ionized calcium-binding adapter molecule 1 (Iba-1) expression and microglial activation in the spinal cord. Results: Mechanical allodynia was exacerbated 11 days after the ligation in PSNL mice. The intranasal administration of NAC alone prevented allodynia exacerbation but failed to provide a therapeutic effect against allodynia in PSNL mice. In contrast, NAC/PPT administration ameliorated PSNL-induced tactile allodynia, with maximum efficacy seen 13 and 14 days after ligation. Western blotting demonstrated that Iba-1 levels tended to increase in PSNL mice compared to controls. This trend of increased Iba-1 levels in PSNL mice was attenuated by the administration of NAC/PPT, but not by NAC alone. Immunohistochemistry revealed an increased number of Iba-1-stained microglia in the ipsilateral spinal cord of PSNL mice, which were significantly suppressed by the administration of NAC/PPT. Conclusions: These results suggest that the post-onset intranasal administration of NAC/PPT ameliorates mechanical allodynia by suppressing microglia induction and that intranasal delivery with PEG-PCL-Tat might be a useful tool for the pharmacological management of neuropathic pain.

Recent progress in nanoparticulate-based intranasal delivery for treating of different central nervous system diseases

Drug administration to the central nervous system (CNS) has become a great obstacle because of several biological barriers, such as the blood-brain barrier, therefore, brain targeting insights are a light for scientists to move forward for treating neurogenerative diseases using advanced non-invasive methods. The current demand is to use a potential direct route as the nasal administration to transport drugs into the brain enhancing the BBB permeability and hence, increasing the bioavailability. Interestingly, recent techniques have been implanted in formulating nanocarriers-based therapeutics for targeting and treating ischemic stroke using lipid or polymeric-based materials. Nanoparticulate delivery systems are set as an effective platform for brain targeting as polymeric nanoparticles and polymeric micelles or nanocarriers based on lipids for preventing drug efflux to promote optimal therapeutic medication concentration in the brain-diseased site. In recent years, there has been a notable increase in research publications and ongoing investigations on the utilization of drug-loading nanocarriers for the treatment of diverse CNS diseases. This review comprehensively depicts these dangerous neurological disorders, drug targeting challenges to CNS, and potential contributions as novel intranasal nano-formulations are being used to treat and regulate a variety of neurological diseases.

Non-Invasive Techniques of Nose to Brain Delivery Using Nanoparticulate Carriers: Hopes and Hurdles

Intranasal drug delivery route has emerged as a promising non-invasive method of administering drugs directly to the brain, bypassing the blood-brain barrier (BBB) and blood-cerebrospinal fluid barriers (BCSF). BBB and BCSF prevent many therapeutic molecules from entering the brain. Intranasal drug delivery can transport drugs from the nasal mucosa to the brain, to treat a variety of Central nervous system (CNS) diseases. Intranasal drug delivery provides advantages over invasive drug delivery techniques such as intrathecal or intraparenchymal which can cause infection. Many strategies, including nanocarriers liposomes, solid-lipid NPs, nano-emulsion, nanostructured lipid carriers, dendrimers, exosomes, metal NPs, nano micelles, and quantum dots, are effective in nose-to-brain drug transport. However, the biggest obstacles to the nose-to-brain delivery of drugs include mucociliary clearance, poor drug retention, enzymatic degradation, poor permeability, bioavailability, and naso-mucosal toxicity. The current review aims to compile current approaches for drug delivery to the CNS via the nose, focusing on nanotherapeutics and nasal devices. Along with a brief overview of the related pathways or mechanisms, it also covers the advantages of nasal drug delivery as a potential method of drug administration. It also offers several possibilities to improve drug penetration across the nasal barrier. This article overviews various in-vitro, ex-vivo, and in-vivo techniques to assess drug transport from the nasal epithelium into the brain.

Nose-to-brain delivery of nanotherapeutics: Transport mechanisms and applications

The blood-brain barrier presents a key limitation to the administration of therapeutic molecules for the treatment of brain disease. While drugs administered orally or intravenously must cross this barrier to reach brain targets, the unique anatomical structure of the olfactory system provides a route to deliver drugs directly to the brain. Entering the brain via receptor, carrier, and adsorption-mediated transcytosis in the nasal olfactory and trigeminal regions has the potential to increase drug delivery. In this review, we introduce the physiological and anatomical structures of the nasal cavity, and summarize the possible modes of transport and the relevant receptors and carriers in the nose-to-brain pathway. Additionally, we provide examples of nanotherapeutics developed for intranasal drug delivery to the brain. Further development of nanoparticles that can be applied to intranasal delivery systems promises to improve drug efficacy and reduce drug resistance and adverse effects by increasing molecular access to the brain. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease.

Cell-Penetrating Peptides as Valuable Tools for Nose-to-Brain Delivery of Biological Drugs

Due to their high specificity toward the target and their low toxicity, biological drugs have been successfully employed in a wide range of therapeutic areas. It is yet to be mentioned that biologics exhibit unfavorable pharmacokinetic properties, are susceptible to degradation by endogenous enzymes, and cannot penetrate biological barriers such as the blood-brain barrier (i.e., the major impediment to reaching the central nervous system (CNS)). Attempts to overcome these issues have been made by exploiting the intracerebroventricular and intrathecal routes of administration. The invasiveness and impracticality of these procedures has, however, prompted the development of novel drug delivery strategies including the intranasal route of administration. This represents a non-invasive way to achieve the CNS, reducing systemic exposure. Nonetheless, biotherapeutics strive to penetrate the nasal epithelium, raising the possibility that direct delivery to the nervous system may not be straightforward. To maximize the advantages of the intranasal route, new approaches have been proposed including the use of cell-penetrating peptides (CPPs) and CPP-functionalized nanosystems. This review aims at describing the most impactful attempts in using CPPs as carriers for the nose-to-brain delivery of biologics by analyzing their positive and negative aspects.

Apoptotic cell death in disease-Current understanding of the NCCD 2023

Apoptosis is a form of regulated cell death (RCD) that involves proteases of the caspase family. Pharmacological and genetic strategies that experimentally inhibit or delay apoptosis in mammalian systems have elucidated the key contribution of this process not only to (post-)embryonic development and adult tissue homeostasis, but also to the etiology of multiple human disorders. Consistent with this notion, while defects in the molecular machinery for apoptotic cell death impair organismal development and promote oncogenesis, the unwarranted activation of apoptosis promotes cell loss and tissue damage in the context of various neurological, cardiovascular, renal, hepatic, infectious, neoplastic and inflammatory conditions. Here, the Nomenclature Committee on Cell Death (NCCD) gathered to critically summarize an abundant pre-clinical literature mechanistically linking the core apoptotic apparatus to organismal homeostasis in the context of disease.

Biodistribution and delivery of oligonucleotide therapeutics to the central nervous system: Advances, challenges, and future perspectives

Considerable advances have been made in the research and development of oligonucleotide therapeutics (OTs) for treating central nervous system (CNS) diseases, such as psychiatric and neurodegenerative disorders, because of their promising mode of action. However, due to the tight barrier function and complex physiological structure of the CNS, the efficient delivery of OTs to target the brain has been a major challenge, and intensive efforts have been made to overcome this limitation. In this review, we summarize the representative methodologies and current knowledge of biodistribution, along with the pharmacokinetic/pharmacodynamic (PK/PD) relationship of OTs in the CNS, which are critical elements for the successful development of OTs for CNS diseases. First, quantitative bioanalysis methods and imaging-based approaches for the evaluation of OT biodistribution are summarized. Next, information available on the biodistribution profile, distribution pathways, quantitative PK/PD modeling, and simulation of OTs following intrathecal or intracerebroventricular administration are reviewed. Finally, the latest knowledge on the drug delivery systems to the brain via intranasal or systemic administration as noninvasive routes for improved patient quality of life is reviewed. The aim of this review is to enrich research on the successful development of OTs by clarifying OT distribution profiles and pathways to the target brain regions or cells, and by identifying points that need further investigation for a mechanistic approach to generate efficient OTs.

Emerging Materials, Wearables, and Diagnostic Advancements in Therapeutic Treatment of Brain Diseases

Among the most critical health issues, brain illnesses, such as neurodegenerative conditions and tumors, lower quality of life and have a significant economic impact. Implantable technology and nano-drug carriers have enormous promise for cerebral brain activity sensing and regulated therapeutic application in the treatment and detection of brain illnesses. Flexible materials are chosen for implantable devices because they help reduce biomechanical mismatch between the implanted device and brain tissue. Additionally, implanted biodegradable devices might lessen any autoimmune negative effects. The onerous subsequent operation for removing the implanted device is further lessened with biodegradability. This review expands on current developments in diagnostic technologies such as magnetic resonance imaging, computed tomography, mass spectroscopy, infrared spectroscopy, angiography, and electroencephalogram while providing an overview of prevalent brain diseases. As far as we are aware, there hasn't been a single review article that addresses all the prevalent brain illnesses. The reviewer also looks into the prospects for the future and offers suggestions for the direction of future developments in the treatment of brain diseases.

Intranasal Administration of N-acetyl-L-cysteine Combined with Cell-Penetrating Peptide-Modified Polymer Nanomicelles as a Potential Therapeutic Approach for Amyotrophic Lateral Sclerosis

Intranasal administration is a promising route for direct drug delivery to the brain; its combination with nanocarriers enhances delivery. We have previously shown that intranasal administration combined with PEG-PCL-Tat (a nanocarrier) efficiently delivers drugs to the brain and exhibits excellent therapeutic efficacy against brain diseases. We aimed to clarify whether intranasal administration combined with PEG-PCL-Tat represents a useful drug delivery system (DDS) for amyotrophic lateral sclerosis (ALS) pharmacotherapy. We used N-acetyl-L-cysteine (NAC) as a model drug with low transferability to the spinal cord and determined the physicochemical properties of NAC/PEG-PCL-Tat. After intranasal administration of NAC/PEG-PCL-Tat, we measured the survival duration of superoxide dismutase-1 G93A mutant transgenic mice (G93A mice), widely used in ALS studies, and quantitatively analyzed the tissue distribution of NAC/PEG-PCL-Tat in ddY mice. The mean particle size and zeta potential of NAC/PEG-PCL-Tat were 294 nm and + 9.29 mV, respectively. Treatment with repeated intranasal administration of NAC/PEG-PCL-Tat considerably prolonged the median survival of G93A mice by 11.5 days compared with that of untreated G93A mice. Moreover, the highest distribution after a single administration of NAC/PEG-PCL-Tat was measured in the spinal cord. These results suggest that intranasal administration combined with PEG-PCL-Tat might represent a useful DDS for ALS therapeutics.

Delivering the Promise of Gene Therapy with Nanomedicines in Treating Central Nervous System Diseases

Central Nervous System (CNS) diseases, such as Alzheimer's diseases (AD), Parkinson's Diseases (PD), brain tumors, Huntington's disease (HD), and stroke, still remain difficult to treat by the conventional molecular drugs. In recent years, various gene therapies have come into the spotlight as versatile therapeutics providing the potential to prevent and treat these diseases. Despite the significant progress that has undoubtedly been achieved in terms of the design and modification of genetic modulators with desired potency and minimized unwanted immune responses, the efficient and safe in vivo delivery of gene therapies still poses major translational challenges. Various non-viral nanomedicines have been recently explored to circumvent this limitation. In this review, an overview of gene therapies for CNS diseases is provided and describes recent advances in the development of nanomedicines, including their unique characteristics, chemical modifications, bioconjugations, and the specific applications that those nanomedicines are harnessed to deliver gene therapies.

Using nanotechnology to deliver biomolecules from nose to brain - peptides, proteins, monoclonal antibodies and RNA

There is a growing number of biomolecules, including peptides, proteins, monoclonal antibodies and RNA, that could be potentially used for the treatment of central nervous system (CNS) diseases. However, the realization of their potential is being hampered by the extraordinary difficulties these complex biomolecules have to reach the brain in therapeutically meaningful amounts. Nose-to-brain (N-to-B) delivery is now being investigated as a potential option for the direct transport of biomolecules from the nasal cavity to different brain areas. Here, we discuss how different technological approaches enhance this N-to-B transport, with emphasis on those that have shown a potential for clinical translation. We also analyse how the physicochemical properties of nanocarriers and their modification with cell-penetrating peptides (CPPs) and targeting ligands affect their efficacy as N-to-B carriers for biomolecules.

Expanding the arsenal against pulmonary diseases using surface-functionalized polymeric micelles: breakthroughs and bottlenecks

Pulmonary diseases such as lung cancer, asthma and tuberculosis have remained one of the common challenges globally. Polymeric micelles (PMs) have emerged as an effective technique for achieving targeted drug delivery for a local as well as a systemic effect. These PMs encapsulate and protect hydrophobic drugs, increase pulmonary targeting, decrease side effects and enhance drug efficacy through the inhalation route. In the current review, emphasis has been placed on the different barriers encountered by the drugs given via the pulmonary route and the mechanism of PMs in achieving drug targeting. The applications of PMs in different pulmonary diseases have also been discussed in detail.

Nose-to-brain/spinal cord delivery kinetics of liposomes with different surface properties

The administration of liposomes via nose-to-brain delivery is expected to become a strategy for efficient drug delivery to the central nervous system. Efficient nose-to-brain delivery and the kinetics of drugs administered in this manner depend on the properties of liposomes. However, there is a lack of basic knowledge of which liposomes are suitable for this purpose. Here, a qualitative study of intranasally administered liposomes (positively charged, neutral, and negatively charged, with or without polyethylene glycol [PEG] modification; particle size <100 nm) was performed to elucidate their dynamics in the brain and spinal cord. Additionally, a quantitative investigation was performed to ascertain their distribution in each part of the brain and spinal cord. The effects of liposome surface charge and PEG modification on the kinetics and distribution post intranasal administration were investigated via two experiments. Qualitative evaluation was performed via ex vivo observation after intranasal administration of fluorescently labeled liposomes. Neutral PEG-modified liposomes were distributed throughout the brain and spinal cord 60 min after administration, and the fluorescence intensity increased with time. By contrast, non-PEG-modified neutral liposomes showed particularly strong fluorescence in the olfactory bulb, and the fluorescence was localized in the anterior part of the brain. Positively charged liposomes showed low fluorescence around the lateral part of the brain and lumbar spinal cord 60 min after administration. Low fluorescence was observed in the whole brain and spinal cord, with strong fluorescence being observed in the olfactory bulb after 120 min of administration. Negatively charged liposomes showed no fluorescence at 60 min after administration, but low fluorescence was observed throughout the brain and spinal cord 120 min after administration. We quantified the radioactivity in the brain and spinal cord after intranasal administration of radioisotope-labeled liposomes. Neutral liposomes showed the highest distribution by area under the drug concentration-time curve (AUC_(60-120)) in the brain and spinal cord compared to other liposomes. Compared with negatively charged liposomes, positively charged liposomes had a higher distribution in the olfactory bulb and forebrain, while negatively charged liposomes had a higher distribution in the hindbrain and bulbospinal tract cord. In addition, the distribution of PEG-modified neutral liposomes in the brain and spinal cord was significantly enhanced compared to that of non-PEG-modified neutral liposomes after 90 min of intranasal administration. These results indicate that surface charge and PEG modification strongly affect the efficiency of nose-to-brain delivery kinetics, and that PEG-modified neutral liposomes are excellent carriers for drug delivery to a wide area of the brain and spinal cord.

Core-shell lipoplexes inducing active macropinocytosis promote intranasal delivery of c-Myc siRNA for treatment of glioblastoma

Glioblastoma is the most common and aggressive primary brain tumor, whose malignancy is closely correlated with elevated proto-oncogene c-myc. Intranasal administration emerges as a potential approach to deliver gene into the brain and interfere c-Myc expression. However, powerful permeability in nasal mucosa, selective delivery to glioma and avoidance of premature release during remote transport are imperative to ensure the therapeutic effectiveness. To address the above concerns, herein we constructed a lipoplex based on pre-compression of c-Myc-targeting siRNA (sic-Myc) by octaarginine and subsequent encapsulation by liposome modified with a selected peptide derived from penetratin, named 89WP. It was found that the lipoplex exhibited a stable core-shell structure and could be preferentially internalized along with cell debris by glioma cells via active macropinocytosis. Through this cellular uptake pathway, the lipoplex avoided being entrapped by lysosome and released siRNA in cytoplasm within 4 h, inducing substantial downregulation of c-Myc mRNA and protein expression of glioma cells. Furthermore, due to significantly enhanced permeability in tumor spheroids and nasal mucosa, the lipoplex was competent to deliver more siRNA to orthotopic glioma after intranasal administration, and therefore prolonged the survival time of glioma-bearing mice by inducing apoptosis. STATEMENT OF SIGNIFICANCE: In the present work, a lipoplex was designed to address the unmet demands on intranasal siRNA delivery to the brain for treatment of glioma. First, a powerful peptide was selected to enable the lipoplex to penetrate nasal mucosa. Second, we found the lipoplex could be selectively internalized along with cell debris by glioma cells via active macropinocytosis, and recorded the entire process. This cellular uptake pathway not only prevented the lipoplex being entrapped by lysosome, but also increased distribution of the lipoplex in orthotopic glioma. Third, this lipoplex provided additional protection for siRNA to avoid premature release during transport from nasal to brain. Overall, this lipoplex improved the gene delivery efficiency of intranasal administration and was promising in the perspective of selectively silencing disease-related genes in intracranial tumor.

Systemic delivery of siRNA to the colon using peptide modified PEG-PCL polymer micelles for the treatment of ulcerative colitis

Ulcerative colitis (UC) is a refractory inflammatory bowel disease that causes inflammation and ulcers in the digestive tract, and significantly reduces the patient's quality of life. While existing UC treatments have many challenges, nanotechnology, and small interfering RNA (siRNA) based formulations are novel and promising for UC treatment. We previously reported that intravenous administration of MPEG-PCL-CH2R4H2C nanomicelles had high inflammatory site accumulation and remarkable therapeutic effects on rheumatoid arthritis by a phenomenon similar to enhanced permeability and retention effect. In this study, we investigated the effects of siRNA delivered using MPEG-PCL-CH2R4H2C nanomicelles through intravenous administration to the inflammation site of dextran sulfate sodium-induced colitis mice. The MPEG-PCL-CH2R4H2C micelles had optimum physical properties and high siRNA compaction ability. Moreover, model-siRNA delivered through MPEG-PCL-CH2R4H2C showed higher accumulation in the inflammatory site than that of the naked siRNA. Furthermore, intravenous administration of MPEG-PCL-CH2R4H2C/siRelA micelles, targeting siRelA, a subunit of NF-κB, significantly decreased the shortening of large intestine, clinical score, and production of inflammatory cytokines compared the 5-ASA and naked siRelA. These results suggest that MPEG-PCL-CH2R4H2C is a useful carrier for the systemic delivery and accumulation of siRNA, thus improving its therapeutic effect.

Total Flavonoids of Chuju Decrease Oxidative Stress and Cell Apoptosis in Ischemic Stroke Rats: Network and Experimental Analyses

Background: Pharmacological research results showed that total flavonoids of Chuju (TFCJ) could be used to treat acute myocardial ischemia and myocardial ischemia-reperfusion injury. In this study, we explored the protective effect of TFCJ on ischemic stroke (IS) in the IS rat model. We hypothesized that TFCJ might exert its neuroprotective effects by suppressing apoptosis and oxidative stress that are closely related to PI3K/Akt/mTOR signaling pathway. Method: TFCJ (10, 20, and 40 mg/kg) was administered for 7 days. Rats (260 ± 20 g) were subjected to middle cerebral artery occlusion (MCAO) for 2 h and reperfusion for 24 h. The neuroprotective effect of TFCJ was substantiated in terms of neurological deficits, oxidative stress (superoxide dismutase, glutathione peroxidase, catalase, and malondialdehyde), pathomorphological changes (HE staining and TUNEL staining), and neurobehavioral functions in the rats. Then, we employed network pharmacology to reveal the potential mechanism of TFCJ against IS. Western blot was used to determine the levels of PI3K/AKT/mTOR pathway proteins. The expression of BCL-2, BAX, and cleaved-Caspase-3 was also measured by Western blots and RT-PCR. Results: The histopathological assessment showed that TFCJ reduced MCAO-induced brain damage. Besides, TFCJ exerted a protective role in MCAO rats by alleviating cell apoptosis and oxidative stress. Network pharmacology showed that TFCJ might be used against IS through the PI3K/AKT signaling pathway. TFCJ reduced cell apoptosis and oxidative stress by increasing the level of p-AKT and p-mTOR in MCAO rats, while the effect of TFCJ was significantly reversed when applying LY294002 (PI3k inhibitor). Conclusion: These results indicated that TFCJ might decrease oxidative stress and apoptosis that are closely related to PI3K/Akt/mTOR pathway in IS. TFCJ is a promising authentic traditional Chinese medicine for the management of IS.

Potential of cell-penetrating peptides (CPPs) in delivery of antiviral therapeutics and vaccines

Viral infections are a great threat to human health. Currently, there are no effective vaccines and antiviral drugs against the majority of viral diseases, suggesting the need to develop novel and effective antiviral agents. Since the intracellular delivery of antiviral agents, particularly the impermeable molecules, such as peptides, proteins, and nucleic acids, are essential to exert their therapeutic effects, using a delivery system is highly required. Among various delivery systems, cell-penetrating peptides (CPPs), a group of short peptides with the unique ability of crossing cell membrane, offer great potential for the intracellular delivery of various biologically active cargoes. The results of numerous in vitro and in vivo studies with CPP conjugates demonstrate their promise as therapeutic agents in various medical fields including antiviral therapy. The CPP-mediated delivery of various antiviral agents including peptides, proteins, nucleic acids, and nanocarriers have been associated with therapeutic efficacy both in vitro and in vivo. This review describes various aspects of viruses including their biology, pathogenesis, and therapy and briefly discusses the concept of CPP and its potential in drug delivery. Particularly, it will highlight a variety of CPP applications in the management of viral infections.

Combination of cell-penetrating peptides with nanomaterials for the potential therapeutics of central nervous system disorders: a review

Although nanomedicine have greatly developed and human life span has been extended, we have witnessed the soared incidence of central nervous system (CNS) diseases including neurodegenerative diseases (Alzheimer's disease, Parkinson's disease), ischemic stroke, and brain tumors, which have severely damaged the quality of life and greatly increased the economic and social burdens. Moreover, partial small molecule drugs and almost all large molecule drugs (such as recombinant protein, therapeutic antibody, and nucleic acid) cannot cross the blood-brain barrier. Therefore, it is especially important to develop a drug delivery system that can effectively deliver therapeutic drugs to the central nervous system for the treatment of central nervous system diseases. Cell penetrating peptides (CPPs) provide a potential strategy for the transport of macromolecules through the blood-brain barrier. This study analyzed and summarized the progress of CPPs in CNS diseases from three aspects: CPPs, the conjugates of CPPs and drug, and CPPs modified nanoparticles to provide scientific basis for the application of CPPs for CNS diseases.

A Network Pharmacology Approach for Exploring the Mechanisms of Panax notoginseng Saponins in Ischaemic Stroke

BACKGROUND

Panax notoginseng saponins (PNS) have been deemed effective herb compounds for treating ischaemic stroke (IS) and improving the quality of life of IS patients. This study aimed to investigate the underlying mechanisms of PNS in the treatment of IS based on network pharmacology.

METHODS

PNS were identified from the Traditional Chinese Medicine System Pharmacology (TCMSP) database, and their possible targets were predicted using the PharmMapper database. IS-related targets were identified from the GeneCards database, OMIM database, and DisGeNET database. A herb-compound-target-disease network was constructed using Cytoscape, and protein-protein interaction (PPI) networks were established with STRING. GO enrichment and KEGG pathway analysis were performed using DAVID. The binding of the compounds and key targets was validated by molecular docking studies using AutoDock Vina. The neuroprotective effect of TFCJ was substantiated in terms of oxidative stress (superoxide dismutase, glutathione peroxidase, catalase, and malondialdehyde) and the levels of IGF1/PI3K/Akt pathway proteins.

RESULTS

A total of 375 PNS targets and 5111 IS-related targets were identified. Among these targets, 241 were common to PNS, and IS network analysis showed that MAPK1, AKT1, PIK3R1, SRC, MAPK8, EGFR, IGF1, HRAS, RHOA, and HSP90AA1 are key targets of PNS against IS. Furthermore, GO and KEGG enrichment analysis indicated that PNS probably exert therapeutic effects against IS by regulating many pathways, such as the Ras, oestrogen, FoxO, prolactin, Rap1, PI3K-Akt, insulin, PPAR, and thyroid hormone signalling pathways. Molecular docking studies further corroborated the experimental results.The network pharmacology results were further verified by molecular docking and in vivo experiments.

CONCLUSIONS

The ameliorative effects of PNS against IS were predicted to be associated with the regulation of the IGF1-PI3K-Akt signalling pathway. Ginsenoside Re and ginsenoside Rb1 may play an important role in the treatment of IS.

Forward Precision Medicine: Micelles for Active Targeting Driven by Peptides

Precision medicine is based on innovative administration methods of active principles. Drug delivery on tissue of interest allows improving the therapeutic index and reducing the side effects. Active targeting by means of drug-encapsulated micelles decorated with targeting bioactive moieties represents a new frontier. Between the bioactive moieties, peptides, for their versatility, easy synthesis and immunogenicity, can be selected to direct a drug toward a considerable number of molecular targets overexpressed on both cancer vasculature and cancer cells. Moreover, short peptide sequences can facilitate cellular intake. This review focuses on micelles achieved by self-assembling or mixing peptide-grafted surfactants or peptide-decorated amphiphilic copolymers. Nanovectors loaded with hydrophobic or hydrophilic cytotoxic drugs or with gene silence sequences and externally functionalized with natural or synthetic peptides are described based on their formulation and in vitro and in vivo behaviors.

Cell-penetrating Peptide-mediated Nanovaccine Delivery

Vaccination with small antigens, such as proteins, peptides, or nucleic acids, is used to activate the immune system and trigger the protective immune responses against a pathogen. Currently, nanovaccines are undergoing development instead of conventional vaccines. The size of nanovaccines is in the range of 10-500 nm, which enables them to be readily taken up by cells and exhibit improved safety profiles. However, low-level immune responses, as the removal of redundant pathogens, trigger counter-effective activation of the immune system invalidly and present a challenging obstacle to antigen recognition and its uptake via antigen-presenting cells (APCs). In addition, toxicity can be substantial. To overcome these problems, a variety of cell-penetrating peptide (CPP)-mediated vaccine delivery systems based on nanotechnology have been proposed, most of which are designed to improve the stability of antigens in vivo and their delivery into immune cells. CPPs are particularly attractive components of antigen delivery. Thus, the unique translocation property of CPPs ensures that they remain an attractive carrier with the capacity to deliver cargo in an efficient manner for the application of drugs, gene transfer, protein, and DNA/RNA vaccination delivery. CPP-mediated nanovaccines can enhance antigen uptake, processing, and presentation by APCs, which are the fundamental steps in initiating an immune response. This review describes the different types of CPP-based nanovaccines delivery strategies.

Quantitative analysis of inulin distribution in the brain focused on nose-to-brain route via olfactory epithelium by reverse esophageal cannulation

This study aimed to determine the effect of intranasal dosing speed and administrating volume of nose-to-brain delivery on candidates for peptide drugs (molecular weight ca. 1-10 kDa). Using inulin as the model molecule of a peptide drug, intranasal administration by cannulation from the airway side through the esophagus was tested in mice. This was done to determine the quantitative distribution levels of the drug in the brain and cerebral spinal fluid (CSF). Distribution levels were increased with slower and constant speed (5 μL/min), with higher dosing volume equivalent to nasal volume per body weight in mice (25 μL), and were recorded 0.27% injected dose per gram of tissue (ID/g) in the brain, and 0.24% injected dose per milliliter (ID/mL) in the CSF at 60 min. Then, brain distribution resulting from reverse cannulation was two times more than that of the typical intranasal administration method using a micropipette. In addition, the percentage of inulin estimated to reach the brain via direct transport (%DTP) during reverse cannulation was estimated to be 93%, suggesting that ~95% of the total dose was transferred directly to the brain via the olfactory mucosa. These results show that distribution of the peptide drug in the brain was increased through constant administration at a slow and constant speed.

Mfn2 Overexpression Attenuates Cardio-Cerebrovascular Ischemia-Reperfusion Injury Through Mitochondrial Fusion and Activation of the AMPK/Sirt3 Signaling

Mitochondria are potential targets for the treatment of cardio-cerebrovascular ischemia–reperfusion (I/R) injury. However, the role of the mitofusin 2 (Mfn2) protein in regulating mitochondrial fusion and cell survival has not been investigated. In the present study, an adenovirus-mediated Mfn2 overexpression assay was performed to understand the effects of Mfn2 on mitochondrial function and cell damage during cardio-cerebrovascular I/R injury. After exposure to I/R injury in vitro, the transcription and expression of Mfn2 were significantly downregulated, which correlated with decreased cell viability and increased apoptosis. By contrast, overexpression of Mfn2 significantly repressed I/R-mediated cell death through modulation of glucose metabolism and oxidative stress. Furthermore, Mfn2 overexpression improved mitochondrial fusion in cells, an effect that was followed by increased mitochondrial membrane potential, improved mitophagy, and inhibition of mitochondria-mediated apoptosis. Our data also demonstrated that Mfn2 overexpression was associated with activation of the AMPK/Sirt3 signaling pathway. Inhibition of the AMPK/Sirt3 pathway abolished the protective effects of Mfn2 on I/R-induced cell injury arising from mitochondrial damage. Our results indicate that Mfn2 protects against cardio-cerebrovascular I/R injury by augmenting mitochondrial fusion and activating the AMPK/Sirt3 signaling pathway.

A Novel Targeted and High-Efficiency Nanosystem for Combinational Therapy for Alzheimer's Disease

Alzheimer's disease (AD) remains the most prevalent neurodegenerative disease, and no effective treatment is available yet. Metal-ion-triggered aggregates of amyloid-beta (Aβ) peptide and acetylcholine imbalance are reported to be possible factors in AD pathogenesis. Thus, a combination therapy that can not only inhibit and reduce Aβ aggregation but also simultaneously regulate acetylcholine imbalance that can serve as a potential treatment for AD is needed. Here, clioquinol (metal-ion chelating agent) and donepezil (acetylcholinesterase (AChE) inhibitor) co-encapsulated human serum albumin (HSA) nanoparticles (dcHGT NPs) are designed, which are modified with transcriptional activator protein (TAT) and monosialotetrahexosylganglioside (GM1). The GM1 lipid and TAT peptide endow this drug delivery nanosystem with high brain entry efficiency and long-term retention capabilities through intranasal administration. It is found that dcHGT NPs can significantly inhibit and eliminate Aβ aggregation, relieve acetylcholine-related inflammation in microglial cells, and protect primary neurons from Aβ oligomer-induced neurotoxicity in vitro. The alleviation of Aβ-related inflammation and AChE-inhibited effect further synergistically adjust acetylcholine imbalance. It is further demonstrated that dcHGT NPs reduce Aβ deposition, ameliorate neuron morphological changes, rescue memory deficits, and greatly improve acetylcholine regulation ability in vivo. This multifunctional synergetic nanosystem can be a new candidate to achieve highly efficient combination therapy for AD.

Anti-Metastatic Effects on Melanoma via Intravenous Administration of Anti-NF-κB siRNA Complexed with Functional Peptide-Modified Nano-Micelles

Controlling metastasis is an important strategy in cancer treatment. Nanotechnology and nucleic acids with novel modalities are promising regulators of cancer metastasis. We aimed to develop a small interfering RNA (siRNA) systemic delivery and anti-metastasis system using nanotechnology. We previously reported that polyethylene glycol-polycaprolactone (PEG-PCL) and functional peptide CH2R4H2C nano-micelle (MPEG-PCL-CH2R4H2C) has high siRNA silencing effects, indicated by increased drug accumulation in tumor-bearing mice, and has an anti-tumor effect on solid tumors upon systemic injection. In this study, we aimed to apply our micelles to inhibit metastasis and evaluated the inhibitory effect of anti-RelA siRNA (siRelA), which is a subunit of NF-κB conjugated with MPEG-PCL-CH2R4H2C, via systemic administration. We report that siRelA/MPEG-PCL-CH2R4H2C had a high cellular uptake and suppressed the migration/invasion of cells in B16F10 cells without toxicity. In addition, in a lung metastasis mouse model using intravenous administration of B16F10 cells treated with siRelA/MPEG-PCL-CH2R4H2C, the number of lung nodules in lung tissue significantly decreased compared to naked siRelA and siControl/MPEG-PCL-CH2R4H2C micelle treatments. Hence, we show that RelA expression can reduce cancer metastasis, and MPEG-PCL-CH2R4H2C is an effective siRNA carrier for anti-metastasis cancer therapies.