Increased Drug Penetration Research Articles

Green synthesis of polyethylene glycol coated, ciprofloxacin loaded CuO nanoparticles and its antibacterial activity against Staphylococcus aureus

Antibacterial resistance requires an advanced strategy to increase the efficacy of current therapeutics in addition to the synthesis of new generations of antibiotics. In this study, copper oxide nanoparticles (CuO-NPs) were green synthesized using Moringa oleifera root extract. CuO-NPs fabricated into a form of aspartic acid-ciprofloxacin-polyethylene glycol coated copper oxide-nanotherapeutics (CIP-PEG-CuO) to improve the antibacterial activity of NPs and the efficacy of the drug with controlled cytotoxicity. These NPs were charachterized by Fourier transform infrared spectroscopy (FTIR), x-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Antibacterial screening and bacterial chemotaxis investigations demonstrated that CIP-PEG-CuO NPs show enhanced antibacterial potential against Gram-positive and Gram-negative clinically isolated pathogenic bacterial strains as compared to CuO-NPs. In ex-vivo cytotoxicity CIP-PEG-CuO-nano-formulates revealed 88% viability of Baby Hamster Kidney 21 cell lines and 90% RBCs remained intact with nano-formulations during hemolysis assay. An in-vivo studies on animal models show that Staphylococcus aureus were eradicated by this newly developed formulate from the infected skin and showed wound-healing properties. By using specially designed nanoparticles that are engineered to precisely transport antimicrobial agents, these efficient nano-drug delivery systems can target localized infections, ensure targeted delivery, enhance efficacy through increased drug penetration through physical barriers, and reduce systemic side effects for more effective treatment.

Enhancing the therapeutic efficacy of gefitinib on subcutaneously transplanted SKOV3 ovarian cancer tumors in nude mice via ultrasound‑stimulated microbubble cavitation.

The present study aimed to explore the effect of ultrasound-stimulated microbubble cavitation (USMC) on drug concentration and therapeutic efficacy of oral gefitinib in treating subcutaneously transplanted SKOV3 ovarian cancer tumors in nude mice. The present study employed the VINNO70 ultrasonic diagnostic and treatment integrated machine for USMC therapy. Firstly, the mechanical index was set at 0.25, and the therapeutic efficacy of USMC treatment was assessed at intervals of 5, 10 and 20 min. Briefly, 72 nude mice were randomized into the following four groups (n=18/group): Control group, USMC5 min group, USMC10 min group and USMC20 min group, and the therapeutic response to USMC treatment was evaluated by comparing pre-and post-intervention effects. Additionally, the combined therapeutic efficacy of USMC and gefitinib was investigated by randomly dividing 96 tumor-bearing mice into the following four groups (n=24/group): Control group, USMC group, gefitinib group and USMC + gefitinib group. Contrast-enhanced ultrasound, hematoxylin and eosin staining, western blotting, immunofluorescence staining, TUNEL staining, ELISA and liquid chromatography-mass spectrometry were performed in the present study. The results showed that USMC combined with gefitinib had the best treatment effect; the tumor inhibition rate was higher than that of gefitinib alone and the overall survival time was prolonged. In addition, the drug concentration in the tumor tissue obtained from the USMC + gefitinib group was revealed to be ~1.4 times higher than that detected in the group treated with gefitinib alone. The experimental results also confirmed that the strongest tumor inhibition rate and longest overall survival time was observed in the USMC + gefitinib group, followed by the gefitinib group and USMC group. STAT3 is an important signaling transducer and transcription factor, which, when phosphorylated, can lead to abnormal cell proliferation and malignant transformation. In addition, the upregulation of phosphorylated (p)-STAT3 is consider a reason for the poor efficacy of gefitinib in treating ovarian cancer. The present study revealed that ultrasound microbubble therapy could overcome this side effect. In conclusion, USMC improved the effects of oral gefitinib on subcutaneously transplanted SKOV3 ovarian cancer tumors in nude mice and increased drug penetration. In addition, USMC overcame the gefitinib-induced side effect of upregulated STAT3 phosphorylation and reduced the expression levels of p-STAT3 in the tumor.

Injectable hybrid hydrogels enable enhanced combination chemotherapy and roused anti-tumor immunity in the synergistic treatment of pancreatic ductal adenocarcinoma

Chemotherapy and immunotherapy have shown no significant outcome for unresectable pancreatic ductal adenocarcinoma (PDAC). Multi-drug combination therapy has become a consensus in clinical trials to explore how to arouse anti-tumor immunity and meanwhile overcome the poorly tumoricidal effect and the stroma barrier that greatly hinders drug penetration. To address this challenge, a comprehensive strategy is proposed to fully utilize both the ferroptotic vulnerability of PDAC to potently irritate anti-tumor immunity and the desmoplasia-associated focal adhesion kinase (FAK) to wholly improve the immunosuppressive microenvironment via sustained release of drugs in an injectable hydrogel for increasing drug penetration in tumor location and averting systematic toxicity. The injectable hydrogel ED-M@CS/MC is hybridized with micelles loaded with erastin that exclusively induces ferroptosis and a FAK inhibitor defactinib for inhibiting stroma formation, and achieves sustained release of the drugs for up to 12 days. With only a single intratumoral injection, the combination treatment with erastin and defactinib produces further anti-tumor performance both in xenograft and KrasG12D-engineered primary PDAC mice and synergistically promotes the infiltration of CD8+ cytotoxic T cells and the reduction of type II macrophages. The findings may provide a novel promising strategy for the clinical treatment of PDAC.

Trilayer dissolving microneedle for transdermal delivery of minoxidil: a proof-of-concept study

Alopecia areata (AA) is a chronic autoimmune disease characterized by bald patches in certain areas of the body, especially the scalp. Minoxidil (MNX), as a first-line treatment of AA, effectively induces hair growth. However, oral and topical administration pose problems, including low bioavailability, risk of uncontrolled hair growth, and local side effects such as burning hair loss, and scalp irritation. In the latest research, MNX was delivered to the skin via microneedle (MN) transdermally. The MNX concentration was distributed throughout the needle so that drug penetration was reduced and had the potential to irritate. In this study, we formulated MNX into three-layer dissolving microneedles (TDMN) to increase drug penetration and avoid irritation. Physicochemical evaluation, parafilm, was used to evaluate the mechanical strength of TDMN and showed that TDMN could penetrate the stratum corneum. The ex-vivo permeation test showed that the highest average permeation result was obtained for TDMN2, namely 165.28 ± 31.87 ug/cm2, while for Minoxidil cream it was 46.03 ± 8.5 ug/cm2. The results of ex vivo and in vivo dermatokinetic tests showed that the amount of drug concentration remaining in the skin from the TDMN2 formula was higher compared to the cream preparation. The formula developed has no potential for irritation and toxicity based on the HET-CAM test and hemolysis test. TDMN is a promising alternative to administering MNX to overcome MNX problems and increase the effectiveness of AA therapy.

Assessment of the in vitro acaricidal activity of Bravecto® (fluralaner) and a proposed orange oil-based formulation vehicle for the treatment of Sarcoptes scabiei

BackgroundSarcoptic mange is a serious animal welfare concern in bare-nosed wombats (Vombatus ursinus). Fluralaner (Bravecto®) is a novel acaricide that has recently been utilised for treating mange in wombats. The topical ‘spot-on’ formulation of fluralaner can limit treatment delivery options in situ, but dilution to a volume for ‘pour-on’ delivery is one practicable solution. This study investigated the in vitro acaricidal activity of Bravecto, a proposed essential oil-based diluent (Orange Power®), and two of its active constituents, limonene and citral, against Sarcoptes scabiei.MethodsSarcoptes scabiei were sourced from experimentally infested pigs. In vitro assays were performed to determine the lethal concentration (LC50) and survival time of the mites when exposed to varying concentrations of the test solutions.ResultsAll compounds were highly effective at killing mites in vitro. The LC50 values of Bravecto, Orange Power, limonene and citral at 1 h were 14.61 mg/ml, 4.50%, 26.53% and 0.76%, respectively. The median survival times of mites exposed to undiluted Bravecto, Orange Power and their combination were 15, 5 and 10 min, respectively. A pilot survival assay of mites collected from a mange-affected wombat showed survival times of < 10 min when exposed to Bravecto and Orange Power and 20 min when exposed to moxidectin.ConclusionsThese results confirm the acaricidal properties of Bravecto, demonstrate acaricidal properties of Orange Power and support the potential suitability of Orange Power and its active constituents as a diluent for Bravecto. As well as killing mites via direct exposure, Orange Power could potentially enhance the topical delivery of Bravecto to wombats by increasing drug penetration in hyperkeratotic crusts. Further research evaluating the physiochemical properties and modes of action of Orange Power and its constituents as a formulation vehicle would be of value.Graphical

Innovative transdermal doxorubicin patches prepared using greenly synthesized iron oxide nanoparticles for breast cancer treatment

ABSTRACT An innovative strategy was formulated to overcome the challenges in delivering doxorubicin (DOX) for breast cancer treatment. Transdermal patches were prepared using carbopol 971 (CP) and polyvinyl alcohol (PVA) loaded with starch-coated iron oxide nanoparticles conjugated to DOX (DOX@St-IONPs). The patches’ physicochemical properties, in vitro drug diffusion, alongside the physical properties of DOX@St-IONPs, and their impact on breast cancer cell lines’ viability were examined. The M1 patch, with a 1:1 CP:PVA ratio and DOX@St-IONPs, showed unique properties, indicating effective delivery. It maintained consistent thickness, weight, and 97% DOX loading. Demonstrated flexibility and acceptable surface pH. M1 displayed fivefold increased drug penetration compared to free DOX patches (flux of 14.85 µg/cm2/h and permeability of 0.95 cm/h), with higher cytotoxicity against triple-negative breast cancer. These results propose promising non-invasive DOX delivery through the developed patches.

A recent review on transungual drug delivery system

The transungual drug delivery system refers to the administration of drugs through the nail plate to treat various nail disorders such as fungal infections, psoriasis, and nail dystrophies. The nail plate is a challenging barrier for drug penetration due to its highly keratinized and tightly packed structure, which limits the permeation of topically applied drugs. Owing to several problems associated with oral therapy, topical therapy remains a preferred treatment option for nail infections due to less side effects, and cost-effectiveness. On the other hand, the drugs that have low permeability across the nail plate highlight the need for further research in this area. Researchers working on various aspects to increase drug penetration across the nail plate, which include the use of chemical penetration enhancers, mechanical methods, and physical methods. Recent advances in transungual drug delivery systems have led to the development of antifungal nail lacquers that can penetrate the nail plate and effectively treat nail infections. Other transungual drug delivery systems under investigation include microneedles, ultrasound, and laser-assisted treatment, which can create micropores in the nail plate allowing higher drug delivery. This indicates the potential of research on transungual drug delivery systems. By understanding the anatomy of the nail, utilizing appropriate penetration-enhancing methods, and selecting appropriate drug formulations, the effectiveness of the system can be developed and utilized.

A Review on Formulation Aspects of Niosomal Gel of Ellagic Acid using Natural Penetration Enhancers

Ellagic acid, a polyphenolic compound present in fruits and berries, with wide spectrum of therapeutic and prophylactic activities. It has wide spectrum of therapeutic, prophylactic and nutritional activities. It is traditionally being used for cosmetic and therapeutic purposes for treating hyperpigmentation, skin cancer and many other skin ailments. Unfortunately Ellagic acid suffers from disadvantages of poor solubility, stability, bioavailability, first pass effect and inter subject variability in gut metabolism. This put serious limit over its use as a therapeutic agent. Recently a focus is being made on improving EA delivery to the site of action using various novel drug delivery systems. Presenting EA topically in vesicular drug delivery as niosomes using natural penetration enhancer as almond oil or olive oil can improve its water solubility and transdermal penetration. It was also learned during literature survey that niosomes act as a good delivery system for hydrophobic drug and serve to increase their dermal penetration. Niosomal gel increases formulation stability and offer to increase drug penetration further and achieve controlled release drug delivery. Literature survey revealed that essential oils as olive, almond or mustard oil act as good natural penetration enhancer for drug in trasndermal gel formulation.

FORMULATION AND EVALUATION OF TRANSDERMAL PATCHES FROM ELEUTHERINE BULBOSA URB. BULB EXTRACT WITH PLASTICIZER VARIATIONS

Objective: This research aimed to develop a transdermal drug delivery system from Eleutherine bulbosa Urb. bulbs as an alternative treatment with minimum side effects compared to other pain medications and increased drug penetration by determining the optimum formula(s) for transdermal patches prepared with varying plasticizer concentrations. Methods: Eleutherine bulbosa Urb. bulbs were extracted by maceration using 96% ethanol. The extract was formed into transdermal patches using the solvent casting method with six formulations (F1-F6) and different types and concentrations of the plasticizer: polyethylene glycol (PEG) 400 or dibutyl phthalate. The derived patches were then evaluated for their organoleptic properties, homogeneity, weight uniformity, thickness, folding endurance, pH level, moisture content, and acceptability (hedonic scale). Results: The evaluation of the physical properties found that all patches were dark brown, opaque, smooth-textured, and had a typical odor of the bulb’s ethanol extract and uniform weight and thickness. Other characteristics included pH ranging from 5.0±0.00 to 5.86±0.04 and a moisture content between 1.04±0.04% and 4.13±0.08%. In addition, the folding endurance was 267 times for F1 and &gt;300 times for F2-F6. The acceptability test using the five-point hedonic scale showed different preferences for these formulas. Conclusion: F6 is the optimum formula for producing transdermal patches with excellent physical properties.

Timolol Maleate in Situ Ophthalmic Mucoadhesive-Thermosensitive Gel: Development and Characterization.

The aim of this study was to prepare a sustained-delivery mucoadhesive-thermosensitive formulation containing poloxamer 338 (P338), poloxamer 188 (P188), and mucoadhesive agents, such as chitosan (CHT) and carboxymethylcellulose (CMC), to increase the ophthalmic bioavailability of timolol maleate (TM). Gels were prepared by mixing different amounts of P338, P188, and a mucoadhesive agent in cold isotonic water using a magnetic stirrer. The sol-gel gelation time of the gels was determined using the test tube inversion method. Viscosity measurements and analysis of the mechanical properties of the gel formulations were performed. In vitro release using dialysis membranes and ex vivo permeation studies using fresh-warmed cow eyes were performed. The gelation times of formulations containing 20:2.5 (P338:P188) and 0.1% CMC and formulations containing 20:2.5 (P338:P188) and 0.1% CHT were 35 s and 26.67 s, respectively. An optimally selected CHT mucoadhesive-thermosensitive in situ gelling system can successfully control the release of moderately hydrophilic drugs, such as TM. In the viscosity study, both formulations showed Newtonian fluid, and the CHT gel's viscosity was found to be higher. The CHT gel showed better mechanical properties than the CMC gel. The amount of TM penetrating the cow cornea after 24 hours was 73.38%, 71.80%, 67.25%, and 60.55% from the CHT gel, CMC gel, TM solution, and commercial preparation, respectively. The improved mucoadhesive-thermosensitive in situ gelling system successfully controlled the release of TM. The significantly lower drainage of TM into the circulation compared with eye drops is an advantage in treating glaucoma, and the use of mucoadhesive agents increases drug penetration.

A novel octa-arginine-modified injectable self-assembling peptide hydrogel for multidrug-resistant cancer therapy

Surgery combined with systemic chemotherapy is currently the main modality of cancer treatment. However, the development of cancer multidrug resistance and inevitable surgical residual lesions lead to high rates of cancer recurrence and mortality. Meanwhile, systemic drug toxic side effects and surgical bleeding complications seriously reduce the quality of life of patients. To avoid cancer multidrug resistance and comprehensively optimize cancer treatment, this work provides a novel injectable cell penetrating peptide octa-arginine (R8)-modified RADA16 (RR) self-assembling peptide nanofiber hydrogel as an anticancer drug carrier for multidrug-resistant cancer therapy. In RR hydrogel, highly compatible RADA16 functions as the β-sheet-based self-assembling backbone which tightly adheres to cancer tissue, prevents postoperative bleeding, and sustainedly releases anticancer drugs for long-term effects. The introduced R8 motifs endow RR hydrogel with the capacity to selectively kill cancer cells and reverse cancer multidrug resistance, which minimally impact normal tissue cells. Specifically, R8 motifs on the hydrogel scaffold selectively interfere with cancer cell membranes, increase drug uptake and penetration into cancer cells and tissues by enhancing multiple internalization pathways, and reduce drug efflux by inhibiting P-gp and BCRP multidrug-resistant transporters. Therefore, this study provides a multifunctional hydrogel material with strong potential for multidrug-resistant cancer clinical translation.

Iontophoresis use for increasing drug penetration into root canals and dentinal tubules: A proof-of-concept study

IntroductionThe success of endodontic treatment depends on the significant disinfection of the root canal system, its irregularities, and dentinal tubules. However, achieving complete disinfection remains challenging, with frequent failures and occurrence of secondary infections. Here, we propose using iontophoresis to increase the penetration and distribution of disinfecting agents into root canals, using methylene blue for proof-of-concept. MethodsThe marker was applied in bovine root canals, and the radial distribution of the dye in the dentinal tubules was evaluated by optical microscopy. Iontophoresis was applied at 0.5 and 1.5 mA for 5 and 15 min. ResultsA significant statistical difference (p < 0.05) was observed in the marker penetration between passive and iontophoretic applications. Both current density and application time had an important effect on methylene blue distribution, with a greater efficacy delivery to the apical region achieved after 1.5 mA for 5 min or 0.5 mA for 15 min, showing longer application time can compensate for lower application current. ConclusionIontophoresis increases the penetration and distribution of methylene blue into bovine root canals and dentinal tubules, including its innermost portions. Clinical significanceIontophoresis has shown to be a promising technique for root canal and dentinal tubule disinfection.

Effects of Hyperthermia and Hyperthermic Intraperitoneal Chemoperfusion on the Peritoneal and Tumor Immune Contexture.

Hyperthermia combined with intraperitoneal (IP) drug delivery is increasingly used in the treatment of peritoneal metastases (PM). Hyperthermia enhances tumor perfusion and increases drug penetration after IP delivery. The peritoneum is increasingly recognized as an immune-privileged organ with its own distinct immune microenvironment. Here, we review the immune landscape of the healthy peritoneal cavity and immune contexture of peritoneal metastases. Next, we review the potential benefits and unwanted tumor-promoting effects of hyperthermia and the associated heat shock response on the tumor immune microenvironment. We highlight the potential modulating effect of hyperthermia on the biomechanical properties of tumor tissue and the consequences for immune cell infiltration. Data from translational and clinical studies are reviewed. We conclude that (mild) hyperthermia and HIPEC have the potential to enhance antitumor immunity, but detailed further studies are required to distinguish beneficial from tumor-promoting effects.

The blood-prostate barrier: an obstacle to drug delivery into the prostate.

The blood-prostate barrier (BPB), a non-static physical barrier, stands as an obstacle between the prostate stroma and the lumen of the prostate gland tube. The barrier has the ability to dynamically regulate and strictly control the mass exchange between the blood and the prostate, thereby limiting drug penetration into the prostate. The basement membrane, fibrous stromal layer, capillary endothelial cell, prostatic ductal epithelial cell, lipid layer, etc., have been confirmed to be involved in the composition of the barrier structure and altered membrane permeability mainly by regulating the size of paracellular ion pores. Various studies have been conducted to improve the efficiency of drug therapy for prostate diseases by changing the administration approaches, improving barrier permeability and increasing drug penetration. To gain a full understanding of BPB, the composition of BPB, the methodology for evaluating the permeability of BPB and alterations in barrier function under pathological conditions are summarized in this review. To find a shortcut for drug delivery across BPB, the biodistribution of drugs in the prostate and different methods of improving drug penetration across BPB are outlined. This review offers an applied perspective on recent advances in drug delivery across BPB.

Recent Progress in Gels for Neuropathic Pain.

Neuropathic pain is a complex and debilitating condition that affects millions of people worldwide. While several treatment options are available, they often have limited efficacy and are associated with adverse effects. In recent years, gels have emerged as a promising option for the treatment of neuropathic pain. Inclusion of various nanocarriers, such as cubosomes and niosomes, into gels results in pharmaceutical forms with higher drug stability and increased drug penetration into tissues compared to products currently marketed for the treatment of neuropathic pain. Furthermore, these compounds usually provide sustained drug release and are biocompatible and biodegradable, which makes them a safe option for drug delivery. The purpose of this narrative review was to provide a comprehensive analysis of the current state of the field and identify potential directions for future research in the development of effective and safe gels for the treatment of neuropathic pain, ultimately improving the quality of life for patients suffering from neuropathic pain.

Reprogramming tumor microenvironment via dual targeting co-delivery of regorafenib and alpha-difluoromethylornithine in osteosarcoma

BackgroundTumor angiogenesis, immunosuppression, and progression are all closely correlated with the tumor microenvironment (TME). Immune evasion is supported by both M2 phenotype tumor-associated macrophages (TAMs) and vascular aberrations in the TME. TME reprogramming is a promising therapeutic approach for treating tumors. Anti-angiogenesis has the power to control the polarization of macrophages, prevent progression, and increase drug penetration. Additionally, polyamine blocking therapy can increase CD8+ T cell infiltration and decrease immunosuppressive cells. These results led to developing a potential therapeutic regimen that targets TAMs and angiogenesis to reprogram the osteosarcoma TME.ResultsFor the targeted biomimetic co-delivery of regorafenib and alpha-difluoromethylornithine via the mannose receptor, which is overexpressed in both TAMs and osteosarcoma cells, mannosylated poly(lactide-co-glycolide)-polyethylene glycol nanoparticles (Man-NPs) were synthesized. The superior physiological properties and intratumoral accumulation of the Man-NPs efficiently promoted TAMs polarization and inhibited angiogenesis. Macrophage repolarization further activated immune cells, which contributed to remodeling the TME.ConclusionOverall, these findings suggested that using Man-NPs as an immunotherapeutic approach to treat osteosarcoma may be promising.Graphical

Controllable release of self-assembled reduction-sensitive paclitaxel dimer prodrug and tetrandrine nanoparticles promotes synergistic therapy against multidrug-resistant cancer

BackgroundMultidrug resistance (MDR) is the main reason for chemotherapy failure. Nanocarriers combined delivery of anti-cancer drugs and MDR inhibitors is an effective strategy to avoid MDR and improve the anti-cancer activity of drugs. MethodsTwo paclitaxel (PTX) molecules are linked by disulfide bonds into PTX2. Then, the PTX2 and tetrandrine (TET) are coated together by mPEG-PLGA self-assembled NPs for combinational treatment. Microstructure, physiological stability, and cytotoxicity are characterized for the co-loaded NPs. ResultsThe NPs exhibit excellent suitability and blood safety for intravenous injection, specifically responsive to pH 6–7, and promptly initiate chemical degradation. Ex vivo fluorescence microscopy image studies indicate that co-loaded NPs increase drug penetration into cancer cells compared with free drugs. MTT assay demonstrates that co-loaded NPs have higher cytotoxicity against HeLa and the flow cytometric analysis shows that co-loaded NPs trigger more apoptosis than the free drugs. Reactive oxygen species (ROS) assay indicates that the drug-loaded NPs generated higher levels of ROS to accelerate apoptosis in HeLa cells. ConclusionsTET can get desirable effects of inhibiting the MDR in advance by binding with the active site on P-gp, then the disulfide bond of PTX2 is broken by glutathione (GSH) in cancer cells and decomposed into PTX to inhibit cancer cell proliferation. General significanceOur studies indicate that the co-loaded NPs can potentially overcome the MDR of conventional chemotherapeutic agents.

Pulsed Ultrasound-Mediated Enhancement on Transscleral and Transconjunctival Fluorescein Sodium Delivery to Rabbit Eye In Vivo.

Purpose: To investigate the efficacy and safety of pulsed ultrasound (PUS) in enhancing fluorescein sodium (NaF) transport to the rabbit eye through the transscleral and transconjunctival routes in vivo. Methods: PUS and NaF were applied onto the supratemporal sclera/conjunctiva of healthy rabbit eyes. PUS (1 MHz, 2.37 W/cm2, 30% duty cycle, 5-min application time) was performed 3 times with a 5-min interval. In the same process, NaF was administered to the eye without PUS in the control. NaF concentrations in the vitreous and retina-choroid were determined by fluorescence measurement. The safety of PUS application was assessed based on temperature and intraocular pressure measurements, clinical observations, electroretinography, histology, and Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling assay. Results: In comparison to the control, higher NaF concentrations were found in the retina-choroid following transscleral (2.45-fold) and transconjunctival (2.97-fold) PUS applications (P < 0.05). NaF concentrations in the vitreous were 3.15 and 5.86 times greater in transscleral and transconjunctival PUS applications, respectively, compared with those obtained without PUS application (P < 0.05), and NaF level in the vitreous after transconjunctival PUS application was 2.61 times that of transscleral PUS application (P < 0.05). Ocular findings were transient and mild conjunctival injection, with no other structural and functional changes in PUS-treated eyes. Conclusions: PUS treatment can improve transscleral and transconjunctival delivery of NaF efficiently and safely. Transscleral and transconjunctival PUS applications offer potential clinical benefit in increasing drug penetration to the posterior segments of the eye for the noninvasive treatment of ocular diseases.

Functional targeted therapy for glioma based on platelet membrane-coated nanogels

Glioma treatment remains a challenge owing to unsatisfactory targeted chemotherapy, where the blood–brain barrier (BBB) hinders the efficient uptake of therapeutics into the brain. Vasculogenic mimicry (VM) formed by invasive glioma cells negatively affects the treatment of glioma. Herein, we developed a targeted biomimetic drug delivery system comprising a doxorubicin-loaded platelet membrane-coated nanogel (DOX@PNGs). The nanogels provide great redox/pH dual responsiveness, while the platelet membrane (PLTM) promotes stability and circulation time. In vitro cellular uptake and in vivo imaging experiments demonstrated that the DOX@PNGs delivery system could penetrate the BBB, target gliomas, and destruct VM. DOX@PNGs increased drug penetration and prolonged mouse survival time during the treatment of orthotopic gliomas. These results indicate this biomimetic drug delivery system to be promising for glioma treatment and may be clinically translated in the future.

Astrocytic scar restricting glioblastoma via glutamate–MAO-B activity in glioblastoma-microglia assembloid

BackgroundGlial scar formation is a reactive glial response confining injured regions in a central nervous system. However, it remains challenging to identify key factors formulating glial scar in response to glioblastoma (GBM) due to complex glia-GBM crosstalk.MethodsHere, we constructed an astrocytic scar enclosing GBM in a human assembloid and a mouse xenograft model. GBM spheroids were preformed and then co-cultured with microglia and astrocytes in 3D Matrigel. For the xenograft model, U87-MG cells were subcutaneously injected to the Balb/C nude female mice.ResultsAdditional glutamate was released from GBM-microglia assembloid by 3.2-folds compared to GBM alone. The glutamate upregulated astrocytic monoamine oxidase-B (MAO-B) activity and chondroitin sulfate proteoglycans (CSPGs) deposition, forming the astrocytic scar and restricting GBM growth. Attenuating scar formation by the glutamate–MAO-B inhibition increased drug penetration into GBM assembloid, while reducing GBM confinement.ConclusionsTaken together, our study suggests that astrocytic scar could be a critical modulator in GBM therapeutics.Graphical