Brain Targeting Research Articles

Endocisternal interfaces for minimally invasive neural stimulation and recording of the brain and spinal cord.

Minimally invasive neural interfaces can be used to diagnose, manage and treat many disorders, with reduced risks of surgical complications. However, endovascular probes lack access to key cortical, subcortical and spinal targets, and are not typically explantable after endothelialization. Here we report the development and testing, in sheep, of endocisternal neural interfaces that approach brain and spinal cord targets through inner and outer spaces filled with cerebrospinal fluid. Thus, the interfaces gain access to the entire brain convexity, to deep brain structures within the ventricles and to the spinal cord from the spinal subarachnoid space. We combined an endocisternal neural interface with wireless miniature magnetoelectrically powered bioelectronics so that it can be freely navigated percutaneously from the spinal space to the cranial subarachnoid space, and from the cranial subarachnoid space to the ventricles. In sheep, we show recording and stimulation functions, as well as repositioning of the flexible electrodes and explantation of the interface after chronic implantation. Minimally invasive endocisternal bioelectronics may enable chronic and transient therapies, particularly for stroke rehabilitation and epilepsy monitoring.

Enhanced delivery of rivastigmine for Alzheimer's disease: Convolvulus pluricaulis lipid hybrid nanoparticles

The study investigates the formulation and characterization of polymeric lipid hybrid nanoparticles (PLHNs) for targeted delivery of Rivastigmine and Convolvulus pluricaulis (C. pluricaulis, Shankhpushpi) extract to the brain. Employing a modified film hydration technique, PLHNs were optimized by adjusting lipid-to-polymer ratios, achieving nanoparticles with optimal size, zeta potential, and entrapment efficiency. The resulting nanoparticles, with sizes between approximately 150–225 nm, exhibited excellent physical stability and encapsulation efficiencies. Characterization through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) confirmed their spherical and smooth morphology. Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) analyses showed no significant interactions between the drug, polymer, and plant extract, ensuring formulation stability. In vitro release studies demonstrated a controlled and sustained drug release, with the optimal formulation showing substantial release over 24 hours. The novel object recognition (NOR) test indicated enhanced cognitive function in animals treated with the optimal formulation, suggesting effective brain targeting and neuroprotective activity. Biochemical analyses supported these findings, revealing significant improvements in antioxidant enzyme levels and reductions in oxidative stress markers in treated animals. This study underscores the potential of PLHNs to enhance the delivery of neuroprotective agents, offering a promising strategy for treating neurodegenerative diseases.

Development of paroxetine loaded nanotransferosomal gel for intranasal delivery with enhanced antidepressant activity in rats

The aim of this study was to develop paroxetine (PXT) loaded nanotransferosomal gel (PXT-NTFG) for intranasal brain delivery. The process involved fabricating PXT-NTFs (paroxetine-loaded nanotransferosomes) through a thin film hydration method and optimizing them based on parameters such as particle size (PS), zeta potential (ZP), polydispersity index (PDI), and entrapment efficiency (EE). The optimized PXT-NTFs exhibited uniform morphology with a PS of 158.30 ± 2.73 nm, low PDI (0.142 ± 0.072), high ZP (21.00 ± 0.75 mV), and excellent EE (88.09 ± 3.40 %). Characterization through various techniques confirmed the incorporation of PXT into the nanotransferosomes and its conversion to amorphous state. Moreover, PXT-NTFG was formulated with suitable viscosity and mucoadhesive properties. In vitro release studies demonstrated sustained drug release from PXT-NTFG at different pH levels as compared to PXT-NTFs and NTF dispersion. Similarly, ex vivo experiments showed 4 folds enhanced drug permeation from PXT-NTFG when compared with PXT conventional gel. Stability studies indicated that the optimized PXT-NTFs remained stable for four months at 4°C and 25°C. Additionally, improved behavioral outcomes, increased neuronal survival rates, and upregulated brain-derived neurotrophic factor (BDNF) expression was observed in lipopolysaccharide (LPS) induced depressed Sprague-Dawley rats after treatment with PXT-NTFG as compared to PXT-dispersion treated and untreated LPS-control groups. Notably, the formulation led to a significant reduction in brain and plasma TNF-α levels. In conclusion, intranasal PXT-NTFG is a promising formulation with sustained drug release, improved brain targeting and enhanced antidepressant activity.

Characterization And Development Of Pegylated Nanoparticles Loaded With Thujone For Improved Brain Targeting

Characterization And Development Of Pegylated Nanoparticles Loaded With Thujone For Improved Brain Targeting

Poloxamer®s anchored with TAT enhance blood–brain barrier penetration of carbamazepine for the treatment of epilepsy: an in vivo study

Carbamazepine is a pharmacological medication commonly prescribed to treat epilepsy. Dose adjustments, poor bioavailability, and prolonged side effects present significant challenges associated with its use. Poloxamer micelles have demonstrated exceptional properties as nanocarriers for drug delivery. This research aimed to develop Poloxamer nanomicelles containing carbamazepine and assess their potential to cross the blood–brain barrier.Poloxamer 407 and P-85 micelles, anchored with TAT as a ligand and containing carbamazepine, were prepared. The morphology, entrapment efficiency, drug release, stability, and toxicity of nanomicelles were examined, along with animal studies conducted to evaluate their anticonvulsant effects. The distribution of carbamazepine-Poloxamer in the brain and plasma was assessed.The results indicated the successful formation of spherical nanomicelles with an average size of less than 100 nm, and carbamazepine was effectively incorporated into the micelles. Formulations composed of mixtures of Poloxamer exhibited a high encapsulation efficiency of approximately 92.1% and remained stable for three months. A sustained release of carbamazepine was observed for up to 72 h. The anticonvulsant effect of carbamazepine-loaded nanomicelles in mice was found to be significantly greater than that of those treated with carbamazepine solution, with the effect increasing by approximately tenfold. Compared to free carbamazepine, the carbamazepine-loaded nanomicelles exhibited a 5.5-fold increase in the brain targeting index, with no toxicity observed in mice treated with these nanomicelles. These findings suggest that Poloxamer micelles represent a promising nanoscale, controlled-release delivery system that is free from toxicity and can enhance the penetration of carbamazepine into the brain while improving its anticonvulsant activity.Graphical

Unveiling the potential of intranasal delivery of renin-angiotensin system drugs: Insights on the pharmacokinetics of irbesartan

The therapeutic interest of renin-angiotensin system (RAS) drugs for the treatment of neuroinflammation has been recently acknowledged. Nevertheless, most RAS drugs display limited passage across the blood–brain barrier (BBB). Therefore, this study investigated the potential of intranasal (IN) delivery of six RAS drugs to circumvent the BBB and attain the brain, envisioning its future use in central nervous system (CNS) neuroinflammatory diseases, such as Alzheimer’s disease (AD).Captopril, enalaprilat, irbesartan, lisinopril, losartan and valsartan were firstly screened based on their impact on the viability of nasal, lung, and neuronal cell lines and their apparent permeability (Papp) across porcine olfactory mucosa. Irbesartan, identified as the one with the best safety and permeability balance, was selected for pharmacokinetic characterization following single and multidose IN administration to CD-1 mice. The results were compared to those obtained by intravenous (IV) injection to assess direct nose-to-brain drug delivery. Olfactory toxicity and anxiety were also evaluated after multidose IN treatment.Irbesartan IN administration significantly enhanced brain targeting, with a 3-fold increase in the maximum concentration (Cmax) and a 2.5-fold increase in the area under the curve (AUCt) in the brain compared to IV route. The drug exhibited a tmax of 15 min post-IN administration and achieved a brain targeting efficiency of 239.56%, with a significant direct transport percentage of 58.26%. Multidose administration indicated no systemic or tissue accumulation, with accumulation ratio (Rac) values below 1.0, and no significant olfactory toxicity.Overall, the study highlights the potential of IN delivery of irbesartan as a promising strategy to improve brain targeting and therapeutic outcomes in CNS diseases such as AD, providing an effective approach to bypass BBB limitations.

Design Formulation of Nanospanlastic Novel Carriers as a Promising Approach to Enhanced Bioavailability in Intranasal Drug Delivery for Sinusitis: Statistical Optimization and In vitro and In vivo Characterization

Background: Most new biologically active chemicals require better water solubility and slower dissolution rates. Cefdinir (CFD) has a very low bioavailability in its crystalline form and is poorly soluble in water. Objective: By preparing cefdinir's spanlastic nanovesicles (SNVs) using the ethanol injection method, the current study has attempted to enhance the drug's solubility and bioavailability using a statistical design approach. Methods: Independent variables, including the nonionic surfactant concentration, edge activator (EA), sonication time, SNVs entrapment efficiency, particle size, zeta potential, PDI, and in vitro release, have been evaluated. The best CFD-SNVs were positioned within in situ gel with muco-adhesive properties made of hydroxypropyl methylcellulose and deacetylated gellan gum. By contrasting intranasal injection of the produced gel with an IV solution, animal models have been used to investigate CFD's systemic and cerebral dynamics. Results: Statistical analysis has suggested an ideal SNVs formulation with nonionic surfactant (65 mg), EA (15 mg), and sonication (3 min). The sol-gel temperature for forming the mucoad-hesive in situ gel containing SNVs has been found to be 34.03°C, and 18.36 minutes has been the extended mucociliary transit time. Following intranasal injection, compared to SNV dispersion, the gelling system has exhibited higher brain bioavailability (2251.9 ± 75 vs. 5281.6 ± 51%, re-spectively). The gel has also demonstrated effective drug targeting of the brain with higher direct transport percentage indices. Conclusion: Mucoadhesive in situ gel with CFD-loaded SNVs can be administered via the in-tranasal route. To enhance bioavailability in the brain and drug targeting from the nose to the brain, nasal in situ gel loaded with CFD-SNVs could be a new carrier to be employed in sinusitis.

Construction and Characterization of Thermosensitive Hydrogel Loaded with Donepezil Nanosuspension and its Application for Transnasal Delivery

AbstractDonepezil (DPZ) is a reversible cholinesterase inhibitor used to treat Alzheimer's disease (AD), while with disadvantages such as gastrointestinal side effects after oral administration and poor adherence in the elderly. The purpose of this study was to develop a thermosensitive hydrogels loaded with donepezil nanosuspension (DPZ‐NS‐gel) for transnasal administration to improve brain targeting and reduce peripheral toxicity. The results of powder X‐ray diffraction and differential scanning calorimeter showed that the crystal type of DPZ changed from form II to form C during the grinding process. DPZ‐NS‐gel was obtained by mixing DPZ‐NS into the blank thermosensitive hydrogel constructed with poloxamer 407 and poloxamer 188. DPZ‐NS‐gel was in sol state at 25 °C and formed gel at 33 °C. Compared with DPZ‐NS, the in vitro release of DPZ‐NS‐gel showed the sustained release profile. In vivo studies indicated that DPZ‐NS‐gel by nasal administration may increase the amount of drug entering into the brain. The in vivo safety evaluation showed no severe inflammatory response and pathological change when DPZ‐NS‐gel was administered by nasal administration. This study provided a promising strategy for clinical application in improving the bioavailability of DPZ in the brain, avoiding oral‐induced gastrointestinal side effects and improving medication adherence in the elderly.

Effects of robot-assisted hand function therapy on brain functional mechanisms: a synchronized study using fNIRS and sEMG.

Robot-assisted hand function therapy is pivotal in the rehabilitation of patients with stroke; however, its therapeutic mechanism remains elusive. Currently, research examining the impact of robot-assisted hand function therapy on brain function in patients with stroke is scarce, and there is a lack of studies investigating the correlation between muscle activity and alterations in brain function. This study aimed to investigate the correlation between forearm muscle movement and brain functional activation by employing the synchronized use of functional near-infrared spectroscopy and surface electromyography methods. Moreover, it sought to compare neural activity patterns during different rehabilitation tasks and refine the mechanism of robot-assisted hand function therapy for post-stroke hand function impairments. Stroke patients with hand dysfunction underwent three sessions of robot-assisted hand function therapy within 2 weeks to 3 months of onset. The fNIRS-sEMG synchronous technique was used to observe brain function and forearm muscle activation. Ten participants were randomly assigned to receive mirror, resistance, or passive rehabilitation training. During the intervention, cortical and muscle activation information was obtained using fNIRS and electromyographic signals. The primary outcomes included changes in oxyhemoglobin concentration and root mean square of surface electromyography. Compared to the resting state, the Oxy-Hb concentration in the brain regions involved in three rehabilitation tasks with robot-assisted hand function therapy significantly increased (p < 0.05). Mirror therapy significantly enhanced the prefrontal cortex and the superior frontal cortex activation levels. In contrast, resistance therapy significantly promoted the activation of the supplementary motor area and the premotor cortex. Passive rehabilitation tasks showed some activation in the target brain area premotor cortex region. Robot-assisted hand function therapy has shown that forearm muscle movement is closely related to oxygenated hemoglobin concentration activity in specific brain regions during different rehabilitation tasks. The simultaneous sEMG-fNIRS study found a significant correlation between muscle movement and brain activity after stroke, which provides an important basis for understanding the treatment mechanism of hand function impairment.

An Update on Recent Drug Delivery Systems Targeting Brain Diseases via the Transnasal Pathway.

To explore the potential of transnasal drug delivery systems (DDS) as an effective means of bypassing the bloodbrain barrier (BBB) for enhanced central nervous system (CNS) targeting, aiming to improve therapeutic outcomes for CNS disorders while reducing systemic side effects. A review of current and emerging DDS technologies, including polymer nanoparticles, liposomes, and micelles, was conducted to assess their suitability for precision-targeted delivery to the brain through the transnasal route. The investigated DDS demonstrate promising capabilities for CNS targeting via the nasal pathway, effectively preserving both the nasal mucosa and CNS integrity. These systems enhance drug precision within neural tissues, potentially improving therapeutic outcomes without harming adjacent tissues. Transnasal DDS offer a promising alternative to traditional delivery methods, with significant potential to advance the treatment of cerebrovascular diseases, neurodegenerative disorders, brain tumors, and psychiatric conditions. This approach represents an evolving frontier in neurotherapeutics, with the potential to transform CNS drug delivery practices.

Analysis of nerve excitability in the dentate gyrus of the hippocampus in cerebral ischaemia-reperfusion mice

Ischemic stroke often leads to cognitive dysfunction, which delays the recovery process of patients. However, its pathogenesis is not yet clear. In this study, the cerebral ischemia-reperfusion model was built as the experimental object, and the hippocampal dentate gyrus (DG) was the target brain area. TTC staining was used to evaluate the degree of cerebral infarction, and nerve cell membrane potentials and local field potentials (LFPs) signals were collected to explore the mechanism of cognitive impairment in ischemia-reperfusion mice. The results showed that the infarcted area on the right side of the brain of the mice in the model group was white. The resting membrane potential, the number of action potential discharges, the post-hyperpolarization potential and the maximum ascending slope of the hippocampal DG nerve cells in the model mice were significantly lower than those in the control group ( P < 0.01); the peak time, half-wave width, threshold and maximum descending slope of the action potential were significantly higher than those in the control group ( P < 0.01). The time-frequency energy values of LFPs signals in the θ and γ bands of mice in the ischemia and reperfusion groups were significantly reduced ( P < 0.01), and the time-frequency energy values in the reperfusion group were increased compared with the ischemia group ( P < 0.01). The signal complexity of LFPs in the ischemia and reperfusion group was significantly reduced ( P < 0.05), and the signal complexity in the reperfusion group was increased compared with the ischemia group ( P < 0.05). In summary, cerebral ischemia-reperfusion reduced the excitability of nerve cells in the DG area of the mouse hippocampus; cerebral ischemia reduced the discharge activity and signal complexity of nerve cells, and the electrophysiological indicators recovered after reperfusion, but it failed to reach the healthy state during the experiment period.

A Wearable, Steerable, Transcranial Low-Intensity Focused Ultrasound System.

Transcranial low-intensity focused ultrasound (LIFU) offers unique opportunities for precisely neuromodulating small and/or deep targets within the human brain, which may be useful for treating psychiatric and neurological disorders. This article presents a novel ultrasound system that delivers focused ultrasound through the forehead to anterior brain targets and evaluates its safety and usability in a volunteer study. The ultrasound system and workflow are described, including neuronavigation, LIFU planning, and ultrasound delivery components. Its capabilities are analyzed through simulations and experiments in water to establish its safe steering range. A cohort of 20 healthy volunteers received a LIFU protocol aimed at the anterior medial prefrontal cortex (amPFC), using imaging and questionnaires to screen for adverse effects. Additional development after the study also analyzes the effect of the skull and sinus cavities on delivered ultrasound energy. Simulations and hydrophone readings agreed with <5% error, and the safe steering range was found to encompass a 1.8 cm × 2.5 cm × 2 cm volume centered at a depth 5 cm from the surface of the skin. There were no adverse effects evident on qualitative assessments, nor any signs of damage in susceptibility-weighted imaging scans. All participants tolerated the treatment well. The interface effectively enabled the users to complete the workflow with all participants. In particular, the amPFC of every participant was within the steering limits of the system. A post hoc analysis showed that "virtual fitting" could aid in steering the beams around subjects' sinuses. The presented system safely delivered LIFU through the forehead while targeting the amPFC in all volunteers, and was well-tolerated. With the capabilities validated here and positive results of the study, this technology appears well-suited to explore LIFU's efficacy in clinical neuromodulation contexts.

Preparation and Pharmacokinetics of Brain-Targeted Nanoliposome Loaded with Rutin.

Rutin is a flavonoid compound with potential for treating Alzheimer's disease, preventing brain damage, mitigating cerebral ischemia-reperfusion injury, and exhibiting anti-glioblastoma activity. However, its efficacy is limited by its low solubility, poor bioavailability, and limited permeability across the blood-brain barrier (BBB). To enhance the bioavailability and brain-targeting ability of Rutin, transferrin-modified Rutin liposome (Tf-Rutin-Lip) was developed using liposomes as a delivery system. Rutin liposomes were prepared using the thin-film dispersion method, and the preparation conditions were optimized using the response surface methodology. Then, transferrin (Tf) was incorporated into the liposomes through covalent modification, yielding Tf-Rutin liposomes. The toxicity of these liposomes on bEnd.3 cells, as well as their impact on the tight junctions of these cells, was rigorously evaluated. Additionally, in vitro and in vivo experiments were conducted to validate the brain-targeting efficacy of the Tf-Rutin liposomes. A susceptible detection method was developed to characterize the pharmacokinetics of Tf-Rutin-Lip further. The optimized conditions for the preparation of Tf-Rutin-Lip were determined as follows: a lipid-to-cholesterol ratio of 4.63:1, a drug-to-lipid ratio of 1:45.84, a preparation temperature of 42.7 °C, a hydration volume of 20 mL, a sonication time of 10 min, a surfactant concentration of 80 mg/mL, a DSPE-MPEG-2000 concentration of 5%, and a DSPE-PEG2000-COOH to DSPE-MPEG-2000 molar ratio of 10%. The liposomes did not affect the cell activity of bEnd.3 cells at 24 h and did not disrupt the tight junction of the blood-brain barrier. Tf-modified liposomes were taken up by bEnd.3 cells, which, in turn, passed through the BBB, thus improving liposomal brain targeting. Furthermore, the results of pharmacokinetic experiments showed that the Cmax, AUC0-∞, AUC0-t, MRT0-∞, and t1/2 of Tf-Rutin-Lip increased 1.99-fold, 2.77-fold, 2.58-fold, 1.26-fold, and 1.19-fold compared to those of free Rutin solution, respectively. These findings suggest that Tf-Rutin-Lip is brain-targeted and may enhance the efficacy of Rutin in the treatment of brain disorders.

Preclinical and first-in-human evaluation of AL002, a novel TREM2 agonistic antibody for Alzheimer’s disease

BackgroundVariants of the gene triggering receptor expressed on myeloid cells-2 (TREM2) increase the risk of Alzheimer’s disease (AD) and other neurodegenerative disorders. Signaling by TREM2, an innate immune receptor expressed by microglia, is thought to enhance phagocytosis of amyloid beta (Aβ) and other damaged proteins, promote microglial proliferation, migration, and survival, and regulate inflammatory signaling. Thus, TREM2 activation has potential to alter the progression of AD. AL002 is an investigational, engineered, humanized monoclonal immunoglobulin G1 (IgG1) antibody designed to target TREM2. In AD mouse models, an AL002 murine variant has been previously shown to induce microglial proliferation and reduce filamentous Aβ plaques and neurite dystrophy.MethodsPreclinical studies assessed the safety, tolerability, pharmacokinetics, and pharmacodynamics of AL002 in cynomolgus monkeys. INVOKE-1 (NCT03635047) was a first-in-human phase 1, randomized, placebo-controlled, double-blind study assessing the safety, tolerability, PK, and PD of AL002 administered as single ascending doses (SAD) in healthy volunteers.ResultsIn cynomolgus monkeys, weekly intravenous injections of AL002 for 4 weeks were well tolerated, dose-dependently decreased soluble TREM2 (sTREM2) in cerebrospinal fluid (CSF) and total TREM2 in hippocampus and frontal cortex, and increased biomarkers of TREM2 signaling in CSF and brain. In the phase 1 study of 64 healthy volunteers, a single intravenous infusion of AL002 demonstrated brain target engagement based on a dose-dependent reduction of sTREM2 in CSF and parallel increases in biomarkers of TREM2 signaling and microglia recruitment. Single-dose AL002 showed central nervous system penetrance and was well tolerated, with no treatment-related serious adverse events over 12 weeks.ConclusionsThese findings support the continued clinical development of AL002 for AD and other neurodegenerative diseases in which TREM2 activation may be beneficial. AL002 is currently being tested in a phase 2, randomized, double-blind, placebo-controlled study in early AD.Trial registrationClinicaltrials.gov, NCT03635047. Registered on August 15, 2018, https://www.clinicaltrials.gov/study/NCT03635047.

Paroxetine Loaded Nanostructured Lipid Carriers Based In-situ Gel for Brain Delivery via Nasal Route for Enhanced Anti-Depressant Effect: In Vitro Prospect and In Vivo Efficacy.

This study focused on developing a thermosensitive gel with nanostructured lipid carriers (NLCs) loaded with paroxetine (PAR) to enhance the treatment and management of depression via nasal administration. Micro emulsion technique was utilized for the PAR-NLCs preparation. The acetyl alcohol and oleic acid were used in the ratio of 76:24. In the NLCs Tween 40, Span40 and Myrj 52 were used as a surfactant. The NLCs were then added into Poloxamer mixture to get thermosensitive NLCs based gel. Characterization, in vitro and in vivo studies were performed to check the efficiency of formulation in drug delivery. The entrapment efficiency of optimized PAR-NLCs was about 90%. The particle size, zeta potential and PDI were 155 ± 1.4nm, -25.9 ± 0.5mV, and 0.12 ± 0.01 respectively. The optimized gel showed a gelling temperature of 31.50 ± 0.50°C and a gelling time of 1 ± 0.12s with a pH of 6, suitable for nasal administration. The in vitro release assay of PAR-NLC-gel showed a cumulative release of about 59% in the first 6h after comparison with PAR-NLCs which showed almost 100%release. In vivo studies included forced swim test and tail suspension tests showed significant potential for treating depression when compared to PAR-NLCs. PAR-NLCs and NLCs based gel enhanced the tissue architecture and suppressed the expression of TNF-α in brain cortex from histological and immunohistochemical analysis. PAR- NLCs gel-based delivery system can prove to be an effective delivery system for brain targeting through nose for the better management of depression.

Genetically engineered human induced pluripotent stem cells for the production of brain-targeting extracellular vesicles

BackgroundExtracellular vesicles (EVs) are cell-secreted membrane vesicles that have become a promising, natural nanoparticle system for delivering either naturally carried or exogenously loaded therapeutic molecules. Among reported cell sources for EV manufacture, human induced pluripotent stem cells (hiPSCs) offer numerous advantages. However, hiPSC-EVs only have a moderate ability for brain delivery. Herein, we sought to develop a stable hiPSC line for producing EVs with substantially enhanced brain targeting by genetic engineering to overexpress rabies viral glycoprotein (RVG) peptide fused to the N terminus of lysosomal associated membrane protein 2B (RVG-Lamp2B) which has been shown capable of boosting the brain delivery of EVs via the nicotinic acetylcholine receptor.MethodsAn RVG-Lamp2B-HA expression cassette was knocked into the AAVS1 safe harbor locus of a control hiPSC line using the CRISPR/Cas9-assisted homologous recombination. Western blot was used to detect the expression of RVG-Lamp2B-HA in RVG-edited hiPSCs as well as EVs derived from RVG-edited hiPSCs. Uptake of EVs by SH-SY5Y cells in the presence of various endocytic inhibitors was analyzed using flow cytometry. Biodistribution and brain delivery of intravenously injected control and RVG-modified EVs in wild-type mice were examined using ex vivo fluorescent imaging.ResultsHere we report that an RVG-Lamp2B-HA expression cassette was knocked into the AAVS1 safe harbor locus of a control hiPSC line using the CRISPR/Cas9-assisted homologous recombination. The RVG-edited iPSCs have normal karyotype, express pluripotency markers, and have differentiation potential. Expression of RVG-Lamp2B-HA was detected in total cell extracts as well as EVs derived from RVG-edited (vs. control) hiPSCs. The RVG-modified EVs enter neuronal cells via distinct endocytic pathways, compared with control EVs. The biodistribution study confirmed that EVs derived from RVG-edited hiPSCs possess higher brain delivery efficiency.ConclusionTaken together, we have established stable, genetically engineered hiPSCs for producing EVs with RVG expression, offering the improved ability for brain-targeted drug delivery.

Brain Abnormalities in Young Single- and Double-Heterozygote Mice for Both Nkx2-1- and Pax8-Null Mutations.

In humans and mice, Nkx2-1 and Pax8 are crucial morphogenic transcription factors defining the early development of the thyroid and specific extrathyroidal tissues. By using 3-month-old single or double heterozygotes for Nkx2-1- and Pax8-null mutations (DHTP) mice, we studied brain abnormalities under different human-like dysthyroidisms, focusing on putative alterations of specific neurotransmitter systems, expression of markers of pre- and post-synaptic function and, given the physio-pathological role mitochondria have in controlling the bioenergetic status of neurons, of mitochondrial dynamics and oxidative balance. Compared to Wt controls, DHTP mice, bearing both systemic and brain hypothyroidism, showed altered expression of synaptic markers, generic and cholinergic (corroborated by immunohistochemistry in caudate, putamen, hippocampus, and basal forebrain) and glutamatergic ones, and reduced expression of key proteins of synaptic plasticity potency and several isoforms of glutamate receptors. The brain of DHTP mice was characterized by lower levels of H2O2 and imbalanced mitochondrial dynamics. Nkx2-1 + / - mice showed dopaminergic neuron-specific alterations, morphologically, more evident in the substantia nigra of DHTP mice. Nkx2-1 + / - mice also showed enhanced mitochondrial biogenesis and oxidative capacity likely as a global response of the brain to Nkx2-1 haploinsufficiency and/or to their elevated T3 circulating levels. Reduced transcription of both tyrosine hydroxylase and dopamine transporter was observed in Pax8 + / - euthyroid mice, suggesting a dopaminergic dysfunction, albeit likely at an early stage, but consistent with the deregulated glucose homeostasis observed in such animals. Overall, new information was obtained on the impact of haploinsufficiency of Pax8 and NKx2-1 on several brain neuroanatomical, molecular, and neurochemical aspects, thus opening the way for future targeting brain dysfunctions in the management of both overt and subclinical thyroid dysfunctions.

Recent opportunities and application of gellan gum based drug delivery system for intranasal route.

In the recent years, in-situ hydrogel based on gellan gum has been investigated for delivery of various drug molecules particularly to treat neurological disorders via intranasal route. The major objective of the present manuscript is to review the recent research studies exploring gellan gum as ionic triggered in-situ gel for intranasal administration to enhance absorption of drugs and to increase their therapeutic efficacy. This review include literature from 1982 to 2023 and were collected from various scientific electronic databases like Scopus, PubMed and Google Scholar to review source, chemistry, ionotropic gelation mechanism, and recent research studies for gellan gum based in-situ hydrogel for intransasl administration.Keywords such as gellan gum, in-situ hydrogel, intranasal administration and brain targeting were used to search literature. The present review included the research studies which explored gellan gum based in-situ gel for intranasal drug delivery. The findings have shown enhanced biavailability of various drugs upon intranasal administration using gellan-gum based in-situ hydrogel.Moreover, the review indicated that intranasal administration of in-situ hydrogel facilitate to overcome blood brain barrier effectively. Hence, significantly higher drug concentration was found to be achieved in brain tissues upon intranasal administration than that of other routes like oral and intravenous. The present work conducted a comprehensive review for gellan gum based in-situ hydrogel particularly for intransal administration to overcome BBB. The study concluded that gellan gum based in-situ hydrogel could be potential promising delivery system for intranasal administration to improve bioavailability and efficacy of drugs specifically to treat neurological disorders.

Exenatide-Modified Deferoxamine-Based Nanoparticles Ameliorates Neurological Deficits in Parkinson's Disease Mice.

To avoid the biotoxicity and poor bioavailability of deferoxamine mesylate (DFO), an iron chelation for the treatment of Parkinson's disease (PD), a self-oriented DFO nanoparticle functionalized with Exendin-4 was developed, which can be targeted delivered into the lesion brain area to achieve synergistic effects against PD by iron chelation and inflammatory suppression. The self-oriented DFO nanoparticles (Ex-4@DFO NPs) were synthesized by double emulsion technique, and characterized in terms of the particle size, morphology and DFO encapsulation efficiency. The cellular internalization, biocompatibility and cytoprotection of NPs were assessed on BV-2 and SH-SY5Y cells. The brain targeting and therapeutic effect of NPs were investigated in MPTP-induced PD mice by near-infrared II fluorescence imaging and immunofluorescence staining, as well as mobility behavioral tests. Ex-4@DFO NPs with a particle size of about 100 nm, showed great biocompatibility and cytoprotection in vitro, which inhibited the decrease of mitochondrial membrane potential of SH-SY5Y cells and the release of inflammatory factors of BV-2 cells. In MPTP-induced PD mice, Ex-4@DFO NPs could penetrate the BBB into brain, and significantly mitigate the loss of dopaminergic neurons and inflammation in the substantia nigra, finally alleviate the mobility deficits. This self-oriented nanosystem not only improved the biocompatibility of DFO, but also enhanced therapeutic effects synergistically by ameliorating neuronal damage and neuroinflammation, showing a potential therapeutic strategy for PD.

Supramolecular cyclodextrin-based reservoir as nasal delivery vehicle for rivastigmine to brain

The purpose of this study involved the synthesis of supramolecular reservoir (i.e. cyclodextrin metal-organic framework, MOF) using cyclodextrins as building blocks, followed by cross-linking to obtain crosslinked CD framework (CDF) using CD-MOF as template and functionalized with borneol (BO) to enhance rivastigmine (RIV) permeation and facilitate brain targeting via intranasal administration. Utilizing BO modified CDF (BO-CDF) with cubic shape as a carrier for the encapsulation of RIV, a nasal RIV delivery system (RIV@BO-CDF) was fabricated. The particle size of RIV@BO-CDF was approximately 250 nm, and the drug loading capacity reached 15 ± 2 %. BO-CDF improved the mucoadhesion and enhanced RIV permeability with the plasma concentration-time curve (AUC), the brain AUC and the peak drug concentration within brain in rats 1.7, 2.3 and 8 times than that of oral RIV solution, respectively. The relative drug targeting efficiency percentage (DTE, 139.4 %) and direct drug transfer percentage (DTP, 28.3 %) of RIV@BO-COF indicated good targeting efficiency and direct nose-to-brain drug delivery. Overall, this study provides a potential application of supramolecular cyclodextrin-based reservoir to enhance the brain targeting and efficacy of the RIV via nasal delivery.