Polylactic-co-glycolic acid-based nanoparticles modified with peptides and other linkers cross the blood-brain barrier for targeted drug delivery

Challenges and material innovations in drug delivery to central nervous system tumors

Central nervous system (CNS) tumors, encompassing a diverse array of neoplasms in the brain and spinal cord, pose significant therapeutic challenges due to their intricate anatomy and the protective presence of the blood-brain barrier (BBB). The primary treatment obstacle is the effective delivery of therapeutics to the tumor site, which is hindered by multiple physiological, biological, and technical barriers, including the BBB. This comprehensive review highlights recent advancements in material science and nanotechnology aimed at surmounting these delivery challenges, with a focus on the development and application of nanomaterials. Nanomaterials emerge as potent tools in designing innovative drug delivery systems that demonstrate the potential to overcome the limitations posed by CNS tumors. The review delves into various strategies, including the use of lipid nanoparticles, polymeric nanoparticles, and inorganic nanoparticles, all of which are engineered to enhance drug stability, BBB penetration, and targeted tumor delivery. Additionally, this review highlights the burgeoning role of theranostic nanoparticles, integrating therapeutic and diagnostic functionalities to optimize treatment efficacy. The exploration extends to biocompatible materials like biodegradable polymers, liposomes, and advanced material-integrated delivery systems such as implantable drug-eluting devices and microfabricated devices. Despite promising preclinical results, the translation of these material-based strategies into clinical practice necessitates further research and optimization.

PLGA nanoparticles encapsulating TSHR-A and rapamycin enhance the induction of dendritic cell-specific immune tolerance in mice with Graves' disease

Dendritic cells (DCs) are the most potent antigen-presenting cells with multifaceted functions in controlling immune activation and tolerance. Graves' disease, particularly Graves' ophthalmopathy, is recognized as a refractory autoimmune thyroid disease. Therefore, DC-targeted therapies aimed at inducing specific immune tolerance are important for the treatment of Graves' disease. Therefore, we utilized polylactic acid glycolic acid polymer (PLGA) polymer nanoparticles (NPs) encapsulating Graves' disease auto-antigen thyrotropin receptor A (TSHR-A) peptide and the immune tolerance inducer rapamycin (Rapa) to synthesize drug-loaded NPs (NP (TSHR-A + Rapa)). We first characterized the synthesized nanodrugs using transmission electron microscopy and dynamic light scattering techniques and tested the uptake capacity of DCs for NPs after co-culturing the NPs with DCs. And the safe concentration of NPs to DCs was detected using Cell counting kit-8 (CCK-8) assay. Subsequently, we tested the targeting and safety of the NPs in mice. And the effects of NPs on the proportion and proliferation of DCs and regulatory T (Treg) cells were examinedin vivoandin vitrousing flow cytometry and 5-ethynyl-2'-deoxyuridine (EdU) method, respectively. Enzyme linked immunosorbent assay (ELISA) assays were used to detect the effect of NPs on cytokine release from DCs. Finally, we tested the preventive and therapeutic effects of the synthesized NPs on disease models. Our results showed that the synthesized NPs were well taken up by DCsin vitro, whilein vivothey were mainly targeted to the spleen of mice. The NPs were able to relatively inhibit the maturation of DCsin vivoandin vitro, while affecting the release of relevant cellular functional factors from DCs, and the NPs also promoted the proportion and proliferation of Treg cellsin vivoandin vitro. In addition, the synthesized NPs were able to prevent and improve the mouse disease model well without toxic side effects on mouse organs and other physiological indicators. Therefore, the synthesis of NP (TSHR-A + Rapa) NPs using PLGA encapsulated TSHR-A and rapamycin could be used as targeting DCs to alter immune tolerance and as a new potential approach for the treatment of Graves' disease.

Temperature-Dependent Aggregation of Tau Protein Is Attenuated by Native PLGA Nanoparticles Under in vitro Conditions

Introduction

Hyperphosphorylation and aggregation of the microtubule-associated tau protein, which plays a critical role in many neurodegenerative diseases (ie, tauopathies) including Alzheimer's disease (AD), are known to be regulated by a variety of environmental factors including temperature. In this study we evaluated the effects of FDA-approved poly (D,L-lactide-co-glycolic) acid (PLGA) nanoparticles, which can inhibit amyloid-β aggregation/toxicity in cellular/animal models of AD, on temperature-dependent aggregation of 0N4R tau isoforms in vitro.

Methods

We have used a variety of biophysical (Thioflavin T kinetics, dynamic light scattering and asymmetric-flow field-flow fractionation), structural (fluorescence imaging and transmission electron microscopy) and biochemical (Filter-trap assay and detection of soluble protein) approaches, to evaluate the effects of native PLGA nanoparticles on the temperature-dependent tau aggregation.

Results

Our results show that the aggregation propensity of 0N4R tau increases significantly in a dose-dependent manner with a rise in temperature from 27°C to 40°C, as measured by lag time and aggregation rate. Additionally, the aggregation of 2N4R tau increases in a dose-dependent manner. Native PLGA significantly inhibits tau aggregation at all temperatures in a concentration-dependent manner, possibly by interacting with the aggregation-prone hydrophobic hexapeptide motifs of tau. Additionally, native PLGA is able to trigger disassembly of preformed 0N4R tau aggregates as a function of temperature from 27°C to 40°C.

Conclusion

These results, taken together, suggest that native PLGA nanoparticles can not only attenuate temperature-dependent tau aggregation but also promote disassembly of preformed aggregates, which increased with a rise of temperature. Given the evidence that temperature can influence tau pathology, we believe that native PLGA may have a unique potential to regulate tau abnormalities associated with AD-related pathology.

Biochemical investigation and in silico analysis of the therapeutic efficacy of Ipriflavone through Tet-1 Surface-Modified-PLGA nanoparticles in Streptozotocin-Induced Alzheimer's like Disease: Reduced oxidative damage and etiological Descriptors

Ipriflavone (IPRI), an isoflavone derivative, is clinically used to prevent postmenopausal bone loss in addition to its antioxidant and cognitive benefits. However, its poor aqueous solubility retained its bioavailability. New strategies have been developed to improve the bioavailability and solubility of neurological medications to enhance their potency and limit adverse effects. This study aimed to prepare targeted IPRI-poly-lactic-co-glycolic acid (PLGA) nanoparticles coupled with Tet-1 peptide to increase the therapeutic potency of IPRI in a rat model of Alzheimer's disease (AD). Streptozotocin (STZ) exacerbates Alzheimer-related alterations by promoting central insulin resistance resulted from defective signaling pathways related to neuroinflammation and neurotoxicity. Bilateral intracerebroventricular (icv) injection of STZ was used to introduce the AD model. Icv-STZ injection significantly affected brain insulin, oxidative stress, inflammatory, and apoptotic indicators and caused behavioral abnormalities. STZ promoted the formation of amyloid β42 (Aβ42) by increasing BACE1 and reducing ADAM10 and ADAM17 expression levels. STZ also triggered the accumulation of neurofibrillary tangles and synaptic dysfunction, which are crucial for neurological impairments. Icv-STZ injection showed evident degenerative changes in the pyramidal cell layer and significantly reduced the count of viable cells in both CA1 and prefrontal cortex, indicating increased neuronal cell death. IPRI successfully ameliorated cognitive dysfunction by improving the phosphorylated forms of cAMP-response element-binding protein (pCREB) and extracellular signal-regulated kinase 1/2 (pERK1/2) related to synaptic plasticity. Targeted IPRI nanoparticles exceeded free IPRI potential in reducing oxidative stress, acetylcholinesterase/monoamine oxidase activities, Tau phosphorylation, and Aβ42 levels revealing less degenerative changes and increased viable neuron counts. IPRI-targeted nanoparticles improved the neuroprotective potential of free IPRI, making this strategy applicable to treat many neurodegenerative diseases. Finally, the in silico study predicted its ability to cross the BBB and to bind various protein targets in the brain.

Mesenchymal stromal cell exosomes for drug delivery of prostate cancer treatments: a review

Interest in prostate cancer as a research topic has gradually increased. As a result, a series of innovative treatment strategies have emerged with an in-depth understanding of the disease. Owing to their unique biological characteristics, mesenchymal stromal cell exosomes (MSC-Exos) have garnered significant attention for their potential to deliver targeted drugs and enable precise prostate cancer treatment. Herein, prostate cancer treatment with MSC-Exos drug-delivery systems is reviewed. This review provides a comprehensive introduction to the advantages of these systems, current research trends and progress, as well as an analysis of current challenges and future research directions. Moreover, this review lays a solid foundation for the continued development and application of MSC-Exos.

High-Strength and Rapidly Degradable Nanocomposite Yarns from Recycled Waste Poly(glycolic acid) (PGA)

Poly(glycolic acid) (PGA) is a rapidly degradable polymer mainly used in medical applications, attributed to its relatively high cost. Reducing its price will boost its utilization in a wider range of application fields, such as gas barriers and shale gas extraction. This article presents a strategy that utilizes recycled PGA as a raw material alongside typical carbon nanomaterials, such as graphene oxide nanosheets (GO) and carbon nanotubes (CNTs), to produce low-cost, fully degradable yarns via electrospinning and twisting techniques. The results demonstrate that the tensile strength of the PGA/GO composite yarn increased to 21.36 MPa, and the elastic modulus attained a value of 259.51 MPa with a 3 wt% of GO loading. The addition of an appropriate amount of GO enhances the tensile resistance of the composite yarns to a certain extent. However, excessive application of GO and CNTs can lead to surface defects in the nanofibers, reducing their mechanical properties. Moreover, the integration of both materials could inhibit the degradation process of PGA to some extent, thereby partially addressing the issue of excessive degradation rates associated with the relatively low molecular weight of recycled PGA.

Bioinspired Approaches for Central Nervous System Targeted Gene Delivery

Disorders of the central nervous system (CNS) which include a wide range of neurodegenerative and neurological conditions have become a serious global issue. The presence of CNS barriers poses a significant challenge to the progress of designing effective therapeutic delivery systems, limiting the effectiveness of drugs, genes, and other therapeutic agents. Natural nanocarriers present in biological systems have inspired researchers to design unique delivery systems through biomimicry. As natural resource derived delivery systems are more biocompatible, current research has been focused on the development of delivery systems inspired by bacteria, viruses, fungi, and mammalian cells. Despite their structural potential and extensive physiological function, making them an excellent choice for biomaterial engineering, the delivery of nucleic acids remains challenging due to their instability in biological systems. Similarly, the efficient delivery of genetic material within the tissues of interest remains a hurdle due to a lack of selectivity and targeting ability. Considering that gene therapies are the holy grail for intervention in diseases, including neurodegenerative disorders such as Alzheimer's disease, Parkinson's Disease, and Huntington's disease, this review centers around recent advances in bioinspired approaches to gene delivery for the prevention of CNS disorders.

Peptide Functionalization of Emulsion-Based Nanocarrier to Improve Uptake across Blood-Brain Barrier

New strategies for enhancing drug delivery to the blood-brain barrier (BBB) represent a major challenge in treating cerebral diseases. Nanoemulsion-based nanocarriers represent an ideal candidate to improve drug delivery thanks to their versatility in functionalization and cargo protection. In this work, a paclitaxel-loaded nano-emulsion has been firstly functionalized and stabilized with two layers constituted of chitosan and hyaluronic acid, and, secondly, the latter has been conjugated to the CRT peptide. CRT is a bioactive peptide that selectively recognizes bEnd.3 cells, a model of the BBB, thanks to its interactions with transferrin (Tf) and its receptor (TfR). Cytotoxic results showed a 41.5% higher uptake of CRT functionalized nano-emulsion than the negative control, demonstrating the ability of this novel tool to be accumulated in brain endothelium tissue. Based upon these results, our approach can be fully generalizable to the design of multifunctional nanocarriers for delivery of therapeutic agents to the central nervous systems.

Brain-targeted Tet-1 peptide-PLGA nanoparticles for berberine delivery against STZ-induced Alzheimer's disease in a rat model: Alleviation of hippocampal synaptic dysfunction, Tau pathology, and amyloidogenesis

Alzheimer's disease (AD) is an age-related neurodegenerative disorder that causes severe dementia and memory loss. Surface functionalized poly(lactic-co-glycolic acid) nanoparticles have been reported for better transport through the blood-brain barrier for AD therapy. This study investigated the improved therapeutic potential of berberine-loaded poly(lactic-co-glycolic acid)/Tet-1 peptide nanoparticles (BBR/PLGA-Tet NPs) in a rat model of sporadic AD. BBR was loaded into the PLGA-Tet conjugate. BBR/PLGA-Tet NPs were physicochemically and morphologically characterized. AD was achieved by bilateral intracerebroventricular (ICV) injection of streptozotocin (STZ). Cognitively impaired rats were divided into STZ, STZ + BBR, STZ + BBR/PLGA-Tet NPs, and STZ + PLGA-Tet NPs groups. Cognitive improvement was assessed using the Morris Water Maze. Brain acetylcholinesterase and monoamine oxidase activities, amyloid β42 (Aβ42), and brain glycemic markers were estimated. Further, hippocampal neuroplasticity (BDNF, pCREB, and pERK/ERK), Tau pathogenesis (pGSK3β/GSK3β, Cdk5, and pTau), inflammatory, and apoptotic markers were evaluated. Finally, histopathological changes were monitored. ICV-STZ injection produces AD-like pathologies evidenced by Aβ42 deposition, Tau hyperphosphorylation, impaired insulin signaling and neuroplasticity, and neuroinflammation. BBR and BBR/PLGA-Tet NPs attenuated STZ-induced hippocampal damage, enhanced cognitive performance, and reduced Aβ42, Tau phosphorylation, and proinflammatory responses. BBR/PLGA-Tet NPs restored neuroplasticity, cholinergic, and monoaminergic function, which are critical for cognition and brain function. BBR/PLGA-Tet NPs may have superior therapeutic potential in alleviating sporadic AD than free BBR due to their bioavailability, absorption, and brain uptake.

Insights into Targeted and Stimulus-Responsive Nanocarriers for Brain Cancer Treatment

Brain cancers, especially glioblastoma multiforme, are associated with poor prognosis due to the limited efficacy of current therapies. Nanomedicine has emerged as a versatile technology to treat various diseases, including cancers, and has played an indispensable role in combatting the COVID-19 pandemic as evidenced by the role that lipid nanocarrier-based vaccines have played. The tunability of nanocarrier physicochemical properties -including size, shape, surface chemistry, and drug release kinetics- has resulted in the development of a wide range of nanocarriers for brain cancer treatment. These nanocarriers can improve the pharmacokinetics of drugs, increase blood-brain barrier transfer efficiency, and specifically target brain cancer cells. These unique features would potentially allow for more efficient treatment of brain cancer with fewer side effects and better therapeutic outcomes. This review provides an overview of brain cancers, current therapeutic options, and challenges to efficient brain cancer treatment. The latest advances in nanomedicine strategies are investigated with an emphasis on targeted and stimulus-responsive nanocarriers and their potential for clinical translation.

Toxicity Evaluation and Controlled-Release of Curcumin-Loaded Amphiphilic Poly-N-vinylpyrrolidone Nanoparticles: In Vitro and In Vivo Models

Curcumin attracts huge attention because of its biological properties: it is antiproliferative, antioxidant, anti-inflammatory, immunomodulatory and so on. However, its usage has been limited by poor water solubility and low bioavailability. Herein, to solve these problems, we developed curcumin-loaded nanoparticles based on end-capped amphiphilic poly(N-vinylpyrrolidone). Nanoparticles were obtained using the solvent evaporation method and were characterized by dynamic and electrophoretic light scattering, transmission electron (TEM) and atomic force (AFM) microscopy. The average particle size was 200 nm, and the ζ-potential was -4 mV. Curcumin-release studies showed that nanoparticles are stable in aqueous solutions. An in vitro release study showed prolonged action in gastric, intestinal and colonic fluids, consistently, and in PBS. In vitro studies on epidermoid carcinoma and human embryonic kidney cells showed that the cells absorbed more curcumin in nanoparticles compared to free curcumin. Nanoparticles are safe for healthy cells and show high cytotoxicity for glioblastoma cells in cytotoxicity studies in vitro. The median lethal dose was determined in an acute toxicity assay on zebrafish and was 23 μM. Overall, the curcumin-loaded nanoparticles seem promising for cancer treatment.

Progress and harmonization of gene editing to treat human diseases: Proceeding of COST Action CA21113 GenE-HumDi

The European Cooperation in Science and Technology (COST) is an intergovernmental organization dedicated to funding and coordinating scientific and technological research in Europe, fostering collaboration among researchers and institutions across countries. Recently, COST Action funded the "Genome Editing to treat Human Diseases" (GenE-HumDi) network, uniting various stakeholders such as pharmaceutical companies, academic institutions, regulatory agencies, biotech firms, and patient advocacy groups. GenE-HumDi's primary objective is to expedite the application of genome editing for therapeutic purposes in treating human diseases. To achieve this goal, GenE-HumDi is organized in several working groups, each focusing on specific aspects. These groups aim to enhance genome editing technologies, assess delivery systems, address safety concerns, promote clinical translation, and develop regulatory guidelines. The network seeks to establish standard procedures and guidelines for these areas to standardize scientific practices and facilitate knowledge sharing. Furthermore, GenE-HumDi aims to communicate its findings to the public in accessible yet rigorous language, emphasizing genome editing's potential to revolutionize the treatment of many human diseases. The inaugural GenE-HumDi meeting, held in Granada, Spain, in March 2023, featured presentations from experts in the field, discussing recent breakthroughs in delivery methods, safety measures, clinical translation, and regulatory aspects related to gene editing.

Magnetically-targetable outer-membrane vesicles for sonodynamic eradication of antibiotic-tolerant bacteria in bacterial meningitis

Treatment of acute bacterial meningitis is difficult due to the impermeability of the blood-brain barrier, greatly limiting the antibiotic concentrations that can be achieved in the brain. Escherichia coli grown in presence of iron-oxide magnetic nanoparticles secrete large amounts of magnetic outer-membrane vesicles (OMVs) in order to remove excess Fe from their cytoplasm. OMVs are fully biomimetic nanocarriers, but can be inflammatory. Here, non-inflammatory magnetic OMVs were prepared from an E. coli strain in which the synthesis of inflammatory lipid A acyltransferase was inhibited using CRISPR/Cas9 mediated gene knockout. OMVs were loaded with ceftriaxone (CRO) and meso-tetra-(4-carboxyphenyl)porphine (TCPP) and magnetically driven across the blood-brain barrier for sonodynamic treatment of bacterial meningitis. ROS-generation upon ultrasound application of CRO- and TCPP-loaded OMVs yielded similar ROS-generation as by TCPP in solution. In vitro, ROS-generation by CRO- and TCPP-loaded OMVs upon ultrasound application operated synergistically with CRO to kill a hard-to-kill, CRO-tolerant E. coli strain. In a mouse model of CRO-tolerant E. coli meningitis, CRO- and TCPP-loaded OMVs improved survival rates and clinical behavioral scores of infected mice after magnetic targeting and ultrasound application. Recurrence did not occur for at least two weeks after arresting treatment.

Synthesis and evaluation of antibacterial activity of transition metal-oleoyl amide complexes

Recent studies show that some metal ions, injure microbial cells in various ways due to membrane breakdown, protein malfunction, and oxidative stress. Metal complexes are suited for creating novel antibacterial medications due to their distinct mechanisms of action and the variety of three-dimensional geometries they can acquire. In this Perspective, the present study focused on new antibacterial strategies based on metal oleoyl amide complexes. Thus, oleoyl amides ligand (fatty hydroxamic acid and fatty hydrazide hydrate) with the transition metal ions named Ag (I), Co (II), Cu (II), Ni (II) and Sn (II) complexes were successfully synthesized in this study. The metals- oleoyl amide were characterized using elemental analysis, and fourier transforms infrared (FTIR) spectroscopy. The antibacterial effect of metals- oleoyl amide complexes was investigated for Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) by analysing minimum inhibitory concentration (MIC), minimal bactericidal concentration (MBC), and scanning electron microscopy (SEM). The results showed that metal-oleoyl amide complexes have high antibacterial activity at low concentrations. This study inferred that metal oleoyl amide complexes could be utilised as a promising therapeutic antibacterial agent.

Ketorolac Loaded Poly(lactic-co-glycolic acid) Coating of AZ31 in the Treatment of Bone Fracture Pain

Biodegradable metal alloys may be successfully used to support bone repair, avoiding second surgery commonly needed when inert metal alloys are used. Combining a biodegradable metal alloy with a suitable pain relief agent could improve patient quality of life. AZ31 alloy was coated using a poly(lactic-co-glycolic) acid (PLGA) polymer loaded with ketorolac tromethamine using the solvent casting method. The ketorolac release profile from the polymeric film and the coated AZ31 samples, the PLGA mass loss of polymeric film, and the cytotoxicity of the optimized coated alloy were assessed. The coated sample showed a ketorolac release that was prolonged for two weeks, which was slower than that of just the polymeric film, in simulated body fluid. PLGA mass loss was complete after a 45-day immersion in simulated body fluid. The PLGA coating was able to lower AZ31 and ketorolac tromethamine cytotoxicity observed in human osteoblasts. PLGA coating also prevents AZ31 cytotoxicity, which was identified in human fibroblasts. Therefore, PLGA was able to control ketorolac release and protect AZ31 from premature corrosion. These characteristics allow us to hypothesize that the use of ketorolac tromethamine-loaded PLGA coating on AZ31 in the management of bone fractures can favor osteosynthesis and relief pain.