The canine blood-brain barrier in health and disease: focus on brain protection

This review examines the role of the canine blood-brain barrier (BBB) in health and disease, focusing on the impact of the multidrug resistance (MDR) transporter P-glycoprotein (P-gp) encoded by the ABCB1/MDR1 gene. The BBB is critical in maintaining central nervous system homeostasis and brain protection against xenobiotics and environmental drugs that may be circulating in the blood stream. We revise key anatomical, histological and functional aspects of the canine BBB and examine the role of the ABCB1/MDR1 gene mutation in specific dog breeds that exhibit reduced P-gp activity and disrupted drug brain pharmacokinetics. The review also covers factors that may disrupt the canine BBB, including the actions of aging, canine cognitive dysfunction, epilepsy, inflammation, infection, traumatic brain injury, among others. We highlight the critical importance of this barrier in maintaining central nervous system homeostasis and protecting against xenobiotics and conclude that a number of neurological-related diseases may increase vulnerability of the BBB in the canine species and discuss its profound impacts on canine health.

Trends development and applications on electrophoresis techniques of slab gel, capillary, microchip/microfluidic capillary, and isotachophoresis

This review describes the various electrophoresis techniques involved in slab gel, capillary, microchip, and isotachophoresis. Each technique offers distinct advantages and limitations in terms of resolution, sensitivity, speed, capacity, and cost of resources. While the manuscript provides an overview of the setup methods for these electrophoresis techniques, it also evaluates their unique characteristics and summarizes a range of analytical applications, including environmental monitoring, proteomics and genomics analysis, clinical diagnostics, pharmaceutical analysis, and biochemical research. This review contributes to the future directions of available electrophoresis techniques and aids knowledge seekers or practitioners in selecting the most appropriate methods for their specific analytical needs. This review highlights the strengths and potential applications of each technique, providing insights into advancing analytical methodologies and exploring emerging trends across scientific disciplines.

Preventive effect of a garlic compound on astrocyte-mediated neuroinflammation in Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by dopaminergic neuron loss and resultant severe motor dysfunction. While current treatments primarily focus on maintaining dopamine levels, effective targeting of neuroinflammation, an important driver of disease progression, remains an unmet need. This study investigates the neuroprotective potential of BMDA (BMDA(N-benzyl-N-methyldecan-1-amine)), a natural compound derived from garlic with strong anti-inflammatory properties, using an MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced mouse model of PD. Behavioral assessments, immunohistochemistry, and dopamine analysis showed that BMDA effectively reduced neuroinflammation and preserved dopaminergic neurons. In vitro studies showed that BMDA significantly suppressed inflammatory markers and reduced astrocyte activation in MPP+-induced primary cultured astrocytes, and real-time PCR confirmed that BMDA attenuated proinflammatory cytokines and chemokines. Further mechanistic studies showed that BMDA inhibited the p-p65 and p-ERK signaling pathways, which underlie astrocyte-mediated neuroinflammation. These findings suggest that BMDA should be considered a therapeutic candidate for PD that targets neuroinflammation.

An overview of work-related stress assessment

OBJECTIVE

Work-related stress (WRS) is associated with the development of various health issues and long-term absence from the workplace. Adequate measurement of WRS is essential to assess its prevalence, risks, and effectiveness of preventive interventions. The aim of this review was to provide an overview of different categories of WRS assessment: 1) self-assessment, 2) external assessment, and 3) biomarkers.

METHODS

The databases MEDLINE, PsycINFO, EMBASE, CINAHL, and Web of Science have been searched until July 2024 for studies comprising self-assessment or external assessment of WRS, and WRS biomarkers. The self-assessment studies were further evaluated following the COSMIN guidelines.

RESULTS

In this review, a total of 15,749 articles were screened. The final analysis included 53 studies on self-assessment of WRS, 33 articles on external assessment of WRS and 167 articles on stress biomarkers. Within self-assessment studies, four instruments were included in the analysis: Job Content Questionnaire, Effort Reward Imbalance Questionnaire, Copenhagen Psychosocial Questionnaire II and the Demand-Control-Support Questionnaire. The studies applying external assessment used job-exposure matrices, work register data, ethnography, digital tools, and external observation. The identified WRS biomarkers were associated with the sympathetic adrenal medullary axis, the hypothalamic pituitary adrenal axis, immune response and inflammation, and haemostatic, metabolic and (epi)genetic biomarkers.

CONCLUSION

The available evidence does not support the claim that there is a singular golden standard for assessing WRS. Inclusion of objective parameters and the interaction with subjective parameters and biological markers has to be studied to receive a broader view of WRS.

Pain in comorbid alcohol use disorder and HIV: A network meta-analysis study

Alcohol use is prevalent among people with HIV (PWH). PWH often experience pain (said discomfort) and use alcohol to combat pain. We reported that short-term alcohol exposure exerts analgesic effect. Prolonged exposure is known to result in chronic pain. We hypothesize that alcohol exposure, either in-vivo for macaques or in-silico simulation exposure onto differentially expressed genes (DEGs) from HIV-1Tg rats and HIV patients, exacerbates discomfort in PWH. To substantiate this hypothesis, we analyzed genomic data collected from three brain datasets including the hippocampus of alcohol-exposed Macaca mulatta (GSE69685), HIV-1Tg rats (GSE47474), and post-mortem brain tissue of HIV-positive patients (GSE28160). Ingenuity Pathway Analysis (IPA)-Core Analysis revealed activation of neuroinflammation, neuropathic pain signaling pathways, and the inhibition of opioid signaling as well as in the increase of neuromuscular disease with neuropathy in Macaca mulatta exposed to binge EtOH and SIV infection. IPA-Core Analysis of the DEGs from HIV-1Tg rats, a rat model that mimics HIV patients on cART, possessing 7 of 9 HIV viral proteins, showed activation of neuroinflammation, neuropathic pain signaling pathways. IPA-Core Analysis of the DEGs from HIV patients showed activation of neuroinflammation and inhibition of neuropathic pain and increase in neuromuscular disease with neuropathy. To study the impact of alcohol exposure in HIV-1Tg rats and HIV patients, in-silico simulation of ethanol (EtOH) treatment mimicking exposure of alcohol onto the DEGs in response to HIV viral proteins in HIV-1Tg rats and HIV infection in HIV patients enhanced discomfort and increased neuromuscular diseases. These molecules showed significant modulation by simulated alcohol exposure, further supporting the link between alcohol use and heightened pain in PWH. Taking together, our findings suggest that alcohol consumption and HIV promote pain via modulating signaling pathways including neuroinflammation, and neuropathic pain signaling pathways and by disease like neuromuscular disease with neuropathy.

A review: Carrier-based hydrogels containing bioactive molecules and stem cells for ischemic stroke therapy

Ischemic stroke (IS), a cerebrovascular disease, is the leading cause of physical disability and death worldwide. Tissue plasminogen activator (tPA) and thrombectomy are limited by a narrow therapeutic time window. Although strategies such as drug therapies and cellular therapies have been used in preclinical trials, some important issues in clinical translation have not been addressed: low stem cell survival and drug delivery limited by the blood-brain barrier (BBB). Among the therapeutic options currently sought, carrier-based hydrogels hold great promise for the repair and regeneration of neural tissue in the treatment of ischemic stroke. The advantage lies in the ability to deliver drugs and cells to designated parts of the brain in an injectable manner to enhance therapeutic efficacy. Here, this article provides an overview of the use of carrier-based hydrogels in ischemic stroke therapy and focuses on the use of hydrogel scaffolds containing bioactive molecules and stem cells. In addition to this, we provide a more in-depth summary of the composition, physicochemical properties and physiological functions of the materials themselves. Finally, we also outline the prospects and challenges for clinical translation of hydrogel therapy for IS.

Manual assessment of cylinder rearing behavior is more sensitive than automated gait evaluations in young, male mice post-stroke of the forepaw somatosensory cortex

BACKGROUND

Stroke is a leading cause of long-term adult disability. Behavioral testing with animal stroke models, which offers a way to evaluate the effectiveness of new interventions, currently relies on methods that are time- and labor-intensive. Automated behavioral assessments of locomotion and gait have been proposed as an alternative, but it is currently unknown whether they are sensitive enough to assess behavioral deficits following stroke of the forepaw somatosensory cortex. The purpose of this study was to compare a validated, manually assessed behavioral test, cylinder rearing (a measure of forepaw asymmetry during exploration), with automated behavior tests of locomotion in a rodent photothrombotic stroke model.

METHODS

We induced a focal photothrombotic stroke in young (12-16 week old) male mice over the left forepaw somatosensory cortex, conducted behavioral testing at acute (48 h) and sub-acute (4 weeks) time points post-stroke, and then correlated behavior deficits to histological measures.

RESULTS

Three automated behavioral tests were used in comparison to cylinder rearing: CatWalk (spontaneous gait), DigiGait (forced treadmill locomotion), and open field (a measure of general locomotor activity). Cylinder rearing testing showed significant forepaw asymmetry between stroke and sham groups acutely and sub-acutely after stroke. Catwalk, DigiGait, and open field tests showed no significant differences between groups. When correlating behavior to histological measures of stroke, the presence of secondary thalamic injury (STI) was associated with forepaw asymmetry on cylinder rearing.

CONCLUSIONS

These findings illustrate the need to find alternative automated behavioral measures for mouse photothrombotic stroke of the forepaw somatosensory cortex.

Integrating untargeted metabolomics and computational docking for biomarker evaluation: A case study on marine algae-derived ligands

In the post-genomic era, liquid chromatography-mass spectrometry (LC-MS) has emerged as a powerful tool for profiling metabolic profiles in marine macroalgae, which are known for their chemical diversity and pharmacological potential. This study integrates untargeted metabolomics and computational chemistry to accelerate the discovery of therapeutic agents from two red algae (Jania rubens and Scinaia fascicularis) and two brown algae (Hydroclathrus clathratus and Sargassum cinereum). LC-MS-based analysis revealed genotypic variations influencing compound structures, functional groups, and physicochemical properties, which correlated with biological activity scores. Ligand-based virtual screening identified lead compounds with high therapeutic potential, while structure-based virtual screening highlighted stigmasta-5,24(28)-dien-3-ol (3α,24Z) (SM) as the top-ranked ligand, exhibiting a binding affinity of -11.40 kcal/mol. Docking optimization at exhaustiveness levels of 8, 16, and 32 demonstrated that level 8 achieved the best balance of accuracy and computational efficiency, completing in 49.74 s. Post-docking evaluation, including statistical analysis, validated the results, with ubiquinol-cytochrome-c reductase protein showing moderate-to-high activity scores for the selected compounds. These findings underscore the potential of marine algae-derived compounds as therapeutic agents, though further in vitro and in vivo studies are needed to confirm their bioactivity. This work highlights the importance of precise extraction and identification of bioactive compounds for advancing marine natural product research.

Molecular mechanisms of programmed cell death and potential targeted pharmacotherapy in ischemic stroke (Review)

Stroke poses a threat to the elderly, being the second leading cause of death and the third leading cause of disability worldwide. Ischemic stroke (IS), resulting from arterial occlusion, accounts for ~85% of all strokes. The pathophysiological processes involved in IS are intricate and complex. Currently, tissue plasminogen activator (tPA) is the only Food and Drug Administration‑approved drug for the treatment of IS. However, due to its limited administration window and the risk of symptomatic hemorrhage, tPA is applicable to only ~10% of patients with stroke. Additionally, the reperfusion process associated with thrombolytic therapy can further exacerbate damage to brain tissue. Therefore, a thorough understanding of the molecular mechanisms underlying IS‑induced injury and the identification of potential protective agents is critical for effective IS treatment. Over the past few decades, advances have been made in exploring potential protective drugs for IS. The present review summarizes the specific mechanisms of various forms of programmed cell death (PCD) induced by IS and highlights potential protective drugs targeting different PCD pathways investigated over the last decade. The present review provides a theoretical foundation for basic research and insights for the development of pharmacotherapy for IS.

Guanylhydrazone and semicarbazone derivatives as potential prototypes for the design of cholinesterase inhibitors against Alzheimer's disease: biological evaluation and molecular modeling studies

Despite being present in many drugs, guanylhydrazones and semicarbazones are two functional groups that have been little investigated as potential therapeutic strategies for the treatment of Alzheimer's disease (AD). For this reason, we initiated the synthesis and evaluation of these compounds as potential anticholinesterase agents, aiming to offer new alternatives for drug development against AD. In the severe phase of AD butyrylcholinesterase (BChE) becomes the main enzyme responsible for the hydrolysis of acetylcholine (ACh). Therefore, in this project, we present the results of BChE inhibitory activity, enzyme kinetics, cytotoxicity, and molecular modeling studies for three guanylhydrazone and two semicarbazone derivatives that were previously synthesized and evaluated as acetylcholinesterase (AChE) inhibitors. Among the compounds tested, guanylhydrazones (1, 2, and 3) showed inhibitory activity against BChE, exhibiting a mixed non-competitive inhibition profile. Specifically, compound 2 (phenanthrenequinone) demonstrated superior inhibitory potency with an IC50 of 0.68 μM, compared to compound 1 (acridinone) with an IC50 of 3.87 μM, and compound 3 (benzodioxole) with an IC50 of 101.7 μM. In contrast, semicarbazones (4 and 5) showed no BChE inhibition up to the highest concentration tested (300 μM). Importantly, all five compounds were found to be non-cytotoxic. Our results suggest that these compounds have potential as drug prototypes targeting different phases of AD. Compounds 3, 4, and 5 may be more effective in the early phase, when AChE activity remains high; compound 1 could be useful in the intermediate phase; and compound 2 appears particularly promising for the severe phase, when BChE plays a more dominant role.

Ultrasound-Assisted Blood-Brain Barrier Opening Monitoring by Photoacoustic and Fluorescence Imaging Using Indocyanine Green

OBJECTIVE

The blood-brain barrier (BBB) is a selectively permeable membrane that restricts drug delivery to the central nervous system. Focused ultrasound (FUS) combined with microbubbles (MBs) is a promising technique to transiently open the BBB, enabling therapeutic delivery. However, real-time monitoring of BBB permeability changes remains challenging. This study investigated the use of indocyanine green (ICG) as a bi-modal contrast agent for photoacoustic and fluorescence imaging to assess BBB opening and closure dynamics.

METHODS

BALB/c mice underwent FUS-mediated BBB opening with different doses of MBs and ICG administration. Photoacoustic and fluorescence imaging were performed at various time points post-FUS to evaluate ICG extravasation dynamics. Magnetic resonance imaging (MRI) with gadolinium contrast was used as the gold standard for BBB permeability assessment. The effect of MB dose and injection timing on BBB closure kinetics was analyzed.

RESULTS

Photoacoustic imaging provided reliable BBB monitoring within the first hour post-FUS, whereas fluorescence imaging was more effective at detecting ICG extravasation at 24 h. A strong correlation was observed between fluorescence intensity and MRI-based contrast enhancement, confirming BBB opening dynamics. BBB closure followed an exponential decay model, with a half-closure time of approximately 81 min. The degree of BBB opening was proportional to the MB dose administered.

CONCLUSION

ICG-based photoacoustic and fluorescence imaging provide a non-invasive and cost-effective alternative to MRI for monitoring FUS-induced BBB opening. These techniques offer complementary temporal windows for assessment, improving the precision of BBB permeability evaluation in preclinical and potentially clinical applications.

Improved feedback loop control for ultrasound-assisted blood-brain barrier opening in non-human primates based on the discrimination between intra- and extra-cerebral cavitation

Objective. Temporary, non-invasive, and localized permeabilization of the blood-brain barrier (BBB) can be achieved through focused ultrasound and microbubbles (MB). This technique has been extensively employed in rodent and non-human primate (NHP) studies for testing various drugs but requires precise control of ultrasonic pressure. However, controlling cavitation in NHP is challenging due to their thicker skull inducing strong ultrasonic attenuation. Furthermore, extra-cranial cavitation may occur masking the cavitation signal at the focal region (cerebral cavitation). Particularly in larger male NHP, temporal muscles are highly perfused and filled with MB.Approach. This study proposes a feedback loop control strategy to distinguish between intra- and extra-cerebral cavitation by analyzing broadband noise recorded by passive cavitation detection sensors.Main results. The frequency-dependent low-pass filtering effect by the skull allows differentiation of distinct frequency components, providing insights into cavitation origin. The present study involved 17 BBB opening experiments in NHP.Significance. Although successful BBB disruption can be achieved in NHP with thin temporal muscles (<5 mm) using a regular feedback loop algorithm, NHP having thicker muscles (>15 mm) require the use of an optimized algorithm able to specifically extract the signature of intra-cerebral cavitation.

Biological effects of rapid short pulses of focused ultrasound for drug delivery to the brain

Focused ultrasound in combination with intravenously injected microbubbles offers a non-invasive and localised method to deliver drugs across the blood-brain barrier, enabling targeted treatment of brain disorders. Recently, we have shown that applying sequences of Rapid Short-Pulses (RaSP; 5 μs pulses emitted at 1.25 kHz grouped into 10 ms bursts) of ultrasound can deliver drugs with an improved efficacy and safety profile compared with traditionally-used longer pulses (> 10 ms). In this study, we examined the extent to which RaSP sequences allowed the extravasation of endogenous blood proteins, including albumin and immunoglobulin, as well as T cells, into the brain parenchyma. We also investigated the effect of RaSP ultrasound treatments on synaptic connectivity, and the distribution and excretion of fluorescently-labelled 3 kDa dextran delivered to the brain with RaSP. The left hippocampus of mice was sonicated with either a RaSP sequence (5 μs at 1.25 kHz in groups of 10 ms at 0.5 Hz) or a long pulse sequence (10 ms at 0.5 Hz), at 0.35, 0.53 and 0.71 MPa with a 1-MHz center frequency. Significantly less albumin was detected in RaSP-treated brains immediately after treatment and was cleared within 10 min compared to those treated with long pulses, while immunoglobulin was hardly detected in RaSP-treated brains at 0, 10 or 20 min after treatment. No T cells were detected in RaSP-treated brains at 0.35, 0.53 or 0.71 MPa after 0 or 2 h. In long pulse samples, however, T cells did extravasate when using the two higher acoustic pressures, 0.53 and 0.71 MPa, immediately after treatment. Quantification of dendritic spine area revealed no differences between RaSP-treated hippocampi compared to untreated contralateral hippocampi and control mice following three weekly ultrasound treatments. Finally, fluorescently-labelled dextran increasingly moved towards blood vessels and away from the parenchyma once delivered to the brain with both RaSP and long pulse sequences. Uptake of dextran within cells decreased over time with both sequences, and long pulses lead to a larger number of vessels with dextran uptake. This study highlights that RaSP ultrasound sequences can deliver molecules across the blood-brain barrier with minimal extravasation of endogenous proteins and no T cell infiltration, while preserving dendritic spine integrity, thus offering an improved safety profile.

Phytochemicals encouraging neurotrophic pathways: brain-derived neurotrophic factors as molecular targets in depression

A complex neuropsychiatric disorder, major depressive disorder (MDD), is linked to dysregulation of neurotrophic factors, neurotransmitter imbalances, and structural changes in the brain. A lack of brain-derived neurotrophic factor (BDNF) has been linked to the pathophysiology of depression. BDNF is critical for neuroplasticity, neuronal viability, and synaptic efficacy. The neurotrophic hypothesis of depression proposes that treatment strategies targeting the BDNF signaling pathway may be promising therapeutic strategies. While traditional antidepressants such as selective serotonin reuptake inhibitors (SSRIs) are known to modulate the expression of BDNF, their use is limited in effectiveness, and a delayed onset of action occurs in many patients. Recent studies have focused on the possibility of the use of phytochemicals as antidepressant agents to target the BDNF pathway. Phytochemicals such as curcumin, resveratrol, quercetin, EGCG, hesperidin, and baicalin have demonstrated neuroprotective and antidepressant-like properties by modulating several key signaling pathways, including the PI3K/Akt/mTOR, MAPK/ERK, and NF-κB/CREB pathways. These compounds increase BDNF expression, promote synaptic plasticity, and mitigate neuroinflammation, contributing to improved mood and cognitive function. Although phytochemicals show considerable preclinical and clinical activity, their clinical usage is limited and characterized by several problems, such as poor bioavailability, poor blood‒brain barrier permeability, and variability in therapeutic response. Several formulation strategies, such as structural modifications and nanoencapsulation, are being explored to improve their pharmacokinetic profiles. These results also highlight the need for larger clinical trials, combination therapies with pharmaceuticals, and mechanistic studies that may clarify the role of phytochemicals in establishing these products as effective and well-tolerated treatments for depression. This narrative review addresses the gap in understanding how plant-derived bioactive compounds can modulate neurotrophic pathways in depression and explores emerging strategies for translating these findings into therapies.

A pilot study for self-guided, active robotic training of proprioception of the upper limb in chronic stroke

BACKGROUND

Proprioceptive impairments of the upper limb are common after stroke. These impairments are not typically addressed during assessment or rehabilitation. Currently, most robotic paradigms for training of the upper limb have focused solely on improving motor function or have targeted proprioception in individuals with combined use of visual feedback. Our goal was to design a training paradigm that directly targets proprioception of the upper limb, while minimizing reliance on other sensory information to improve sensorimotor function after stroke.

METHODS

In this pilot study, 5 individuals with stroke and 5 age-matched controls were tested on a single-day proprioceptive training paradigm. Here, participants used a joystick with their less-affected arm to send commands to a KINARM exoskeleton that would passively move their more-affected arm. To complete the passive reaching task, participants relied only on proprioceptive feedback from the more-affected arm and were only given knowledge of results information after each trial. Sensorimotor function of the upper limb was measured pre- and post-training via robotic measures of motor function [Visually Guided Reaching (VGR)] and position sense [Arm Position Matching (APM)]. Sensorimotor function was quantified as a Task Score, which incorporated multiple task-relevant parameters for both VGR and APM. Changes in sensorimotor performance due to training were calculated as the pre- to post-training difference for VGR and APM within the control and stroke groups.

RESULTS

We found significant improvements from pre-training to post-training for VGR in individuals with stroke (p < 0.001, CLES = 100) that were not observed in control participants (p = 0.87, CLES = 80). We observed significant changes from pre- to post-training in both VGR (Posture Speed, Reaction Time, Initial Direction Angle, Min-Max Speed Difference, and Movement Time) and APM (Contraction/Expansion Ratiox and Shifty) parameters.

CONCLUSIONS

Our novel proprioceptive training paradigm is one of the first to implement a self-guided sensory training protocol. We observed improvements in motor function and proprioception for individuals with stroke. This pilot study demonstrates the feasibility of self-guided proprioceptive training to improve motor and sensory function in individuals with stroke. Future studies aim to examine multi-day training to examine longer-term impacts on upper limb sensorimotor function.

Bacopa monnieri: Preclinical and Clinical Evidence of Neuroactive Effects, Safety of Use and the Search for Improved Bioavailability

Bacopa monnieri, also known as Brahmi or Waterhyssop, is a plant used in Ayurveda for its memory-enhancing properties and control of blood sugar levels. It contains active compounds such as alkaloids, saponins, and cucurbitacins, which have various biological activities. The plant has been studied for its potential in treating Alzheimer's disease, Parkinson's disease, attention deficit hyperactivity disorder (ADHD), and depression. Animal studies have shown promising results in reducing symptoms and protecting against neurodegeneration. Concerning safety, Bacopa monnieri has been found to be generally non-toxic, with no serious side effects reported. However, interactions with certain medications and contraindications in conditions like hyperthyroidism should be considered. Further research is needed to determine optimal dosages and ensure safety, especially for pregnant and breastfeeding women.

A novel in silico approach for predicting unbound brain-to-plasma ratio using machine learning-based support vector regression

The blood-brain barrier (BBB) functions as a vital protective mechanism, restricting the entry of substances and xenobiotics into the central nervous system (CNS). Consequently, BBB penetration is a critical aspect of absorption, distribution, metabolism, elimination, and toxicity (ADME/Tox) considerations in drug discovery and development as it is essential to minimize CNS-associated side effects in systemically targeted drugs and to enhance efficacy in CNS-targeted therapeutics. In this study, an in silico model utilizing the novel machine learning-based hierarchical support vector regression (HSVR) scheme was developed to predict the unbound brain-to-plasma concentration ratio (Kp,uu,brain) values using a diverse dataset of compounds with known BBB penetration properties. The HSVR model leverages a hierarchical framework to capture the complex relationships between molecular descriptors and BBB penetration mechanisms that can otherwise be insurmountably difficult for traditional methods or other machine learning algorithms. These complexities arise from the fact that BBB penetration can be governed by various factors, including passive diffusion and active influx and efflux transport processes. The accuracy, predictivity, robustness of HSVR were rigorously validated using comprehensive valuation metrics and stringent validation criteria. Its practical application was further substantiated through a mock test. Comparative analyses revealed that the HSVR model outperforms existing published models both quantitatively and qualitatively, providing a reliable tool for early-stage drug discovery and development. The adoption of this model has the potential to significantly streamline BBB penetration assessments, minimizing reliance on in vivo studies while expediting the identification of viable CNS drug candidates or systemic drug candidates prone to CNS-related challenges. This approach aligns seamlessly with the "fail early and fail fast" paradigm of modern drug discovery, enhancing both efficiency and cost-effectiveness.

Small organism models for mode of action research on anti-ageing and nootropic herbs, foods, and formulations

With global increase in ageing population along with increasing age-related neurodegenerative diseases (NDs), development of sustainable, safe and effective solutions for promoting healthy ageing and preventing diseases has become a priority. Traditional healthcare systems/medicines prescribe several herbs, foods and formulations to promote healthy ageing and prevent and/or treat age-related diseases. However, the scientific data elucidating their mechanism of action is very limited and deeper research using different models is warranted for timely and wider use. The clinical studies and research with higher model organisms, although useful, have several practical, technical, and financial limitations. Conversely, small organism models like Yeast, Roundworm, Fruit fly, and Zebrafish, which have genetic similarities to humans, can replicate the disease features and provide behavioural, cellular and molecular insights. The common features of ageing and NDs, like amyloid protein aggregations, oxidative stress, energy dysregulation, inflammation and neurodegeneration can be mimicked in the small organism models for Alzheimer's, Parkinson's, Huntington's diseases, and Amyotrophic Lateral Sclerosis. This review focuses on small organism model- based research unveiling interesting modes of action and synergistic effects of herbal extracts, foods, and formulations, which are indicated especially for healthy ageing and management of NDs. This will provide leads for the quick and sustainable development of scientifically evaluated solutions for clinically relevant, age-related conditions.

MEF-Net: Multi-scale and edge feature fusion network for intracranial hemorrhage segmentation in CT images

Intracranial Hemorrhage (ICH) refers to cerebral bleeding resulting from ruptured blood vessels within the brain. Delayed and inaccurate diagnosis and treatment of ICH can lead to fatality or disability. Therefore, early and precise diagnosis of intracranial hemorrhage is crucial for protecting patients' lives. Automatic segmentation of hematomas in CT images can provide doctors with essential diagnostic support and improve diagnostic efficiency. CT images of intracranial hemorrhage exhibit characteristics such as multi-scale, multi-target, and blurred edges. This paper proposes a Multi-scale and Edge Feature Fusion Network (MEF-Net) to effectively extract multi-scale and edge features and fully fuse these features through a fusion mechanism. The network first extracts the multi-scale features and edge features of the image through the encoder and the edge detection module respectively, then fuses the deep information, and employs the multi-kernel attention module to process the shallow features, enhancing the multi-target recognition capability. Finally, the feature maps from each module are combined to produce the segmentation result. Experimental results indicate that this method has achieved average DICE scores of 0.7508 and 0.7443 in two public datasets respectively, surpassing those of several advanced methods in medical image segmentation currently available. The proposed MEF-Net significantly improves the accuracy of intracranial hemorrhage segmentation.

Microfluidic and Computational Tools for Neurodegeneration Studies

Understanding the molecular, cellular, and physiological components of neurodegenerative diseases (NDs) is paramount for developing accurate diagnostics and efficacious therapies. However, the complexity of ND pathology and the limitations associated with conventional analytical methods undermine research. Fortunately, microfluidic technology can facilitate discoveries through improved biomarker quantification, brain organoid culture, and small animal model manipulation. Because this technology can increase experimental throughput and the number of metrics that can be studied in concert, it demands more sophisticated computational tools to process and analyze results. Advanced analytical algorithms and machine learning platforms can address this challenge in data generated from microfluidic systems, but they can also be used outside of devices to discern patterns in genomic, proteomic, anatomical, and cognitive data sets. We discuss these approaches and their potential to expedite research discoveries and improve clinical outcomes through ND characterization, diagnosis, and treatment platforms.

A pharmacological vasoconstrictor cocktail targeting endothelin signalling generates a stable, reproducible focal cerebral infarct with associated functional deficits in mice

Necessary for enhanced understanding of brain injury, and for developing new therapies, is the generation of reliable animal models. While many models are available, each comes with benefits and limitations. Intracerebral injection of the vasoconstrictive peptide endothelin-1 creates one of the most widely adopted models of focal ischemic stroke in rats, yet its potency is underwhelming in mice. This is likely underpinned by the greater proportions of vasodilatory compared to vasoconstrictive receptor subtypes in the mouse brain. Yet mouse models of ischemic stroke provide the benefit of exploiting the wide range of transgenic strains that can aid in further understanding pathophysiology mechanisms of acute and secondary damage, as well as endogenous recovery. To improve the efficiency of focal endothelin-1 infarcts in mice, we investigated the impact of co-administering pharmacological compounds that target endothelin receptor subtypes and downstream signalling, aimed at selectively enhancing vasoconstriction whilst reducing vasodilation. We report exacerbated neuronal loss and tissue atrophy resulting in motor and cognitive dysfunction when endothelin-1 was co-administered with the nitric oxide synthase inhibitor L-NAME and the selective ETB1 antagonist RES-701-1. These infarcts were stable, reproducible and achievable across brain regions. These findings demonstrate a new and effective mouse model to study focal ischemic stroke.

Roles of Adam8 in Neuroinflammation in experimental ischemic Stroke: Insights from single-cell and ribosome-bound mRNA sequencing

Stroke remains a leading cause of global mortality, with neuroinflammation significantly exacerbating clinical outcomes. Microglia serve as key mediators of post-stroke neuroinflammation, though the mechanisms driving their migration to injury sites remain poorly understood. In this study, using publicly available single-cell sequencing data (GSE234052), we identified a migration-associated microglial subtype in a murine model of distal middle cerebral artery occlusion (dMCAO). Additionally, ribosome-bound mRNA sequencing data (GSE225110) from microglia isolated from peri-infarct cortical tissue uncovered dMCAO-induced alterations in microglial mRNA translation. By integrating these datasets, we identified A Disintegrin And Metalloproteinase 8 (Adam8) as a key gene upregulated at both the transcriptional and translational levels post-dMCAO. Protein analysis revealed that both the precursor and active forms of Adam8 were predominantly expressed in microglia and significantly upregulated in peri-infarct regions following dMCAO. Notably, Adam8 inhibition with BK-1361 significantly reduced Adam8 cleavage, M1 microglial migration, inflammation, infarct size, and improved neurological outcomes. Bioinformatics analysis further identified Myo1e as a potential interacting partner of Adam8, a finding validated through immunofluorescence co-localization. These findings highlight Adam8 as a promising therapeutic target for mitigating post-stroke neuroinflammation and offer new insights into the mechanisms of microglial migration.

Biomonitoring of metals in the blood and urine of waste recyclers from exposure to airborne fine particulate matter (PM2.5)

This is the first systematic investigation of occupational exposure to toxic metals among waste recyclers in municipal waste recycling facilities. Concentrations of heavy metals (HMs) in the blood and urine of exposed recyclers in different jobs were compared to control groups (administrative department), identifying possible work-related and socio-demographic exposure factors. The potential relationship between HMs levels in PM2.5 and HM concentrations in the blood and urine of recyclers was studied for ten elements. Mean concentrations of HMs of recyclers were significantly higher than for the control group. Over 50% of the waste recyclers had HM levels higher than the recommended limits. The study revealed that most of the waste recyclers engaged in a minimum of three tasks, posing a challenge in establishing a correlation between specific tasks and the levels of elements monitored through biomonitoring. Co levels in blood and Fe levels in the urine of waste recyclers have a significant relationship with the increase in daily working hours. Among the variables related to the participant's demographic information, the level of education and monthly income were significantly different compared to the control group. Also, a significant correlation was found between HM levels in PM2.5 personal exposure and recyclers' urine and blood. Management controls include workflow or, in other words, alternate relocation of workers exposed to severe risks. Engineering controls such as ventilation systems, applying appropriate personal protective equipment (PPE), and risk management methods are the implementation cases to reduce exposure.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40201-024-00924-y.

Delivering Gd-Labeled IgG Antibodies Into the Mouse Brain Following Focused Ultrasound Treatment

OBJECTIVE

Antibody-based therapy has emerged as a powerful tool for targeted treatment of neurological diseases, such as brain cancer and neurodegenerative disorders. However, direct, scalable, and safe confirmation of antibody delivery into the brain remains challenging. Antibodies can be effectively tracked when tagged with molecules that are detectable by medical imaging modalities, such as MRI, PET, or SPECT. In this study, we aimed to confirm gadolinium (Gd)-labeled IgG antibody delivery into the mouse brain using MRI, following exposure to focused ultrasound (FUS) and circulating microbubbles.

METHODS

We acquired MR images of the mouse brain to evaluate antibody delivery into the targeted brain region. First, we quantified the MR signal of Gd-labeled IgG antibodies in phantoms using preclinical 9.4 T and clinical 3 T MRI scanners. Then, we determined optimal ultrasound and MR imaging parameters to non-invasively and safely disrupt the blood-brain barrier in a localized and reversible manner and effectively monitor antibody delivery into the murine brain, respectively.

RESULTS

We confirmed that IgG antibodies can be reliably delivered into the murine brain using FUS and microbubble treatment and that we can track their biodistribution within the brain parenchyma using clinically relevant MR image sequences. The maximum detected volume of Gd-IgG antibody delivery (n = 4) was determined to be 0.12 ± 0.02 mm3 at t = 75.3 ± 17.3 minutes following treatment.

CONCLUSION

This work paves the way for a scalable and non-ionizing method for performing and evaluating antibody delivery into the brain.

Biofeedback-Based Videogame May Improve Rage Attacks in Tourette Syndrome

Background: Approximately 20%-40% of individuals with Tourette syndrome (TS) have rage attacks (RAs), which are recurrent, explosive behavioral outbursts that can cause significant functional impairment. Despite the impact of RA in TS, there has been limited research on treatment, and most studies have focused on pharmacologic interventions. Nonpharmacologic interventions have the potential to improve symptoms with fewer side effects. Mightier, a video game-based biofeedback therapy, may help teach emotional regulation through heart rate control and has the potential to improve RA in youth with TS. Objective: To evaluate the feasibility and acceptability of Mightier as a therapeutic intervention for RA in youth with TS. Methods: Subjects aged 6-12 years old with a diagnosis of TS and RA were enrolled between October 2021 and May 2022 into a 20-week single-arm trial. Feasibility was assessed by the rate of enrollment, screen failures, and retention and device engagement. We also evaluated efficacy by assessing rage severity (Clinical Global Impressions of Rage), Rage Outbursts and Anger Rating Scale (ROARS) and overall aggression severity (Modified Overt Aggression Scale [MOAS]) pre- and postintervention. CGI-Improvement (CGI-I) was completed postintervention. Results: We enrolled 11 participants. The study was feasible based on enrollment rate (one participant every 2.5 months), screen failures (n = 1), and retention rate (91%). Mean weekly play time was 38 (SD 18) minutes/week. No adverse effects were reported. Median rage severity scores improved across all assessment measures. All participants reported overall improvement on the post-intervention CGI-I. Conclusions: This Mightier study was feasible in terms of recruitment and retention. Participants with TS and RA used the device often and engaged with the device throughout the 12-week intervention period. Rage severity overall improved across the various outcome measures, and all participants had at least some improvement by parent report. Mightier may be a helpful tool for reducing rage severity in children with RA and TS.

Efficacy and toxicity of stereotactic radiotherapy combined with third-generation EGFR-TKIs and immunotherapy in patients with brain metastases from non-small cell lung cancer

OBJECTIVE

Stereotactic radiotherapy (SRT) is fast gaining attention as a preferred treatment alternative for patients with brain metastases (BM) from non-small cell lung cancer (NSCLC). In this study, we examined the efficacy and safety of combining SRT with immunotherapy (IT) and targeted therapy (TT), either separately or concurrently with the aim to formulate an optimal therapeutic regimen for patients with NSCLC BM.

METHODS

The combination therapy were comprised of IT and TT agents. For the SRT-combined TT agents group, TT was limited to third-generation EGFR-TKIs. The administration of these drugs within 30 days before or after SRT was defined as combination therapy. The primary endpoint was 1-year progression-free survival (PFS), which was evaluated by a blinded independent review committee and categorized into local recurrence at the radiation site and the emergence of new distant intracranial metastases. Secondary endpoints included confirmed intracranial objective response rate (IORR) and intracranial disease control rate in the overall population. Post-treatment grading was performed according to CTCAE, and the levels of radiation necrosis were differentiated.

RESULTS

The 266 patients with NSCLC BM were categorized into the following four groups based on their treatment methods: SRT alone, SRT combined with IT, SRT combined with third-generation EGFR-TKIs, and SRT combined with both IT and TT. For the local radiation range, the 1‑year PFS of these four groups were 77.89% (P = 0.239), 88.75% (P = 0.266), 88.01% (P = 0.210), and 91.97% (P = 0.057), respectively. For new intracranial metastases outside of the radiotherapy site, the corresponding values were 63.96% (P = 0.039), 74.17% (P = 0.258), 88.70% (P = 0.024), and 87.81% (P = 0.015), respectively. By the end of the study period, the IORR increased from 32% with SRT alone to 46% in the IT group, 58% in the TT group, and 61% in the SRT combined with both the IT and TT groups. However, the group that received SRT in combination with IT and TT exhibited a higher occurrence rate of grade 3 adverse events, and a statistically significant difference was observed in grade 3 radiation necrosis.

CONCLUSION

For NSCLC BM, IT, TT, or both together with SRT increased the distant intracranial tumor control. Nonetheless, combining SRT with both IT and TT increased the occurrence rate of acute adverse events. Thus, while SRT provided good local control independently, the incidence of symptomatic RN was low.

Revisiting the critical roles of reactive microglia in traumatic brain injury

Traumatic brain injury (TBI) triggers a complex neuroinflammatory cascade, with microglia serving as key regulators of both pathological damage and tissue structural restoration. Despite extensive research, the precise temporal evolution of microglial activation and its implications for long-term neurological outcomes remain incompletely understood. Here, we provide a comprehensive review of the molecular and cellular mechanisms underlying microglial responses in TBI, highlighting their role in neuroinflammation, neurogenesis, and tissue remodeling. We systematically compare clinical and preclinical TBI classifications, lesion patterns, and animal modeling strategies, evaluating their translational relevance. Furthermore, we explore the limitations of the conventional M1/M2 dichotomy and emphasize recent insights from single-cell transcriptomic analyses that reveal distinct microglial subpopulations across different injury phases. Finally, we discuss current therapeutic strategies targeting microglial modulation and propose future directions for neuroimmune interventions in TBI. By integrating findings from experimental and clinical studies, this review aims to bridge mechanistic insights with therapeutic advancements, paving the way for precision-targeted neuroimmune therapies.

Exploring immunotherapeutic strategies for neurodegenerative diseases: a focus on Huntington's disease and Prion diseases

Immunotherapy has emerged as a promising therapeutic approach for the treatment of neurodegenerative disorders, which are characterized by the progressive loss of neurons and impaired cognitive functions. In this review, active and passive immunotherapeutic strategies that help address the underlying pathophysiology of Huntington's disease (HD) and prion diseases by modulating the immune system are discussed. The current landscape of immunotherapeutic strategies, including monoclonal antibodies and vaccine-based approaches, to treat these diseases is highlighted, along with their potential benefits and mechanisms of action. Immunotherapy generally works by targeting disease-specific proteins, which serve as the pathological hallmarks of these diseases. Additionally, the review addresses the challenges and limitations associated with immunotherapy. For HD, immunotherapeutic approaches focus on neutralizing the toxic effects of mutant huntingtin and tau proteins, thereby reducing neurotoxicity. Immunotherapeutic approaches targeting flanking sequences, rather than the polyglutamine tract in the mutant huntingtin protein, have yielded promising outcomes for patients with HD. In prion diseases, therapies attempt to prevent or eliminate misfolded proteins that cause neurodegeneration. The major challenge in prion diseases is immune tolerance. Approaches to overcome the highly tolerogenic nature of the prion protein have been discussed. A common hurdle in delivering antibodies is the blood‒brain barrier, and strategies that can breach this barrier are being investigated. As protein aggregation and neurotoxicity are related, immunotherapeutic strategies being developed for other neurodegenerative diseases could be repurposed to target protein aggregation in HD and prion diseases. While significant advances in this field have been achieved, continued research and development are necessary to overcome the existing limitations, which will help in shaping the future of immunotherapy as a strategy for managing neurological disorders.

Astrocytes of the hippocampus and responses to periprandial neuroendocrine hormones

Astrocytes have risen as stars in the field of energy homeostasis and neurocognitive function, acting as a bridge of communication between the periphery and the brain, providing metabolic support, signaling via gliotransmitters, and altering synaptic communication. Dietary factors and energy state have a profound influence on hippocampal function, and the hippocampus is critical for appropriate behavioral responses associated with feeding and internal hunger cues (being in the fasted or full state), but how the hippocampus senses periprandial status and is impacted by diet is largely unknown. Periprandial hormones act within the hippocampus to modulate processes involved in hippocampal-dependent learning and memory function and astrocytes likely play an important role in modulating this signaling. In addition to periprandial hormones, astrocytes are positioned to respond to changes in circulating nutrients like glucose. Here, we review literature investigating how astrocytes mediate changes in hippocampal function, highlighting astrocyte location, morphology, and function in the context of integrating glucose metabolism, neuroendocrine hormone action, and/or cognitive function in the hippocampus. Specifically, we discuss research findings on the effects of insulin, ghrelin, leptin, and GLP-1 on glucose homeostasis, neural activity, astrocyte function, and behavior in the hippocampus. Because obesogenic diets impact neuroendocrine hormones, astrocytes, and cognitive function, we also discuss the effects of diet and diet-induced obesity on these parameters.

Advances in brain-targeted delivery strategies and natural product-mediated enhancement of blood-brain barrier permeability

The blood-brain barrier (BBB) represents a formidable challenge in the treatment of neurological disorders, as it restricts the passage of most therapeutic agents into the central nervous system (CNS). Research in brain-targeted delivery strategies and explore in natural products for BBB modulation have opened new avenues for effective CNS drug delivery. This review highlights the latest developments in molecular-based delivery systems, cell-based approaches, physical techniques, toxicity concerns, clinical trials and artificial intelligence (AI) -driven modeling for brain-targeted drug delivery. Additionally, it examines the role of natural products, particularly aromatic resuscitation medicines, in enhancing BBB permeability through modulating tight junction proteins and inhibiting efflux transporters. It is emphasized that the integration of natural products with modern drug delivery systems offers promising opportunities for the development of novel brain-targeted therapies. However, challenges related to the complexity and variety of natural product compositions must be addressed to fully realize their potential. This review underscores the importance of continued research into the molecular mechanisms underlying BBB modulation and natural product-mediated nano-delivery strategies for CNS disorders.

Flavonoids and their role in oxidative stress, inflammation, and human diseases

Oxidative stress and chronic inflammation are important drivers in the pathogenesis and progression of many chronic diseases, such as cancers of the breast, kidney, lung, and others, autoimmune diseases (rheumatoid arthritis), cardiovascular diseases (hypertension, atherosclerosis, arrhythmia), neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease), mental disorders (depression, schizophrenia, bipolar disorder), gastrointestinal disorders (inflammatory bowel disease, colorectal cancer), and other disorders. With the increasing demand for less toxic and more tolerable therapies, flavonoids have the potential to effectively modulate the responsiveness to conventional therapy and radiotherapy. Flavonoids are polyphenolic compounds found in fruits, vegetables, grains, and plant-derived beverages. Six of the twelve structurally different flavonoid subgroups are of dietary significance and include anthocyanidins (e.g. pelargonidin, cyanidin), flavan-3-ols (e.g. epicatechin, epigallocatechin), flavonols (e.g. quercetin, kaempferol), flavones (e.g. luteolin, baicalein), flavanones (e.g. hesperetin, naringenin), and isoflavones (daidzein, genistein). The health benefits of flavonoids are related to their structural characteristics, such as the number and position of hydroxyl groups and the presence of C2C3 double bonds, which predetermine their ability to chelate metal ions, terminate ROS (e.g. hydroxyl radicals formed by the Fenton reaction), and interact with biological targets to trigger a biological response. Based on these structural characteristics, flavonoids can exert both antioxidant or prooxidant properties, modulate the activity of ROS-scavenging enzymes and the expression and activation of proinflammatory cytokines (e.g., interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α)), induce apoptosis and autophagy, and target key signaling pathways, such as the nuclear factor erythroid 2-related factor 2 (Nrf2) and Bcl-2 family of proteins. This review aims to briefly discuss the mutually interconnected aspects of oxidative and inflammatory mechanisms, such as lipid peroxidation, protein oxidation, DNA damage, and the mechanism and resolution of inflammation. The major part of this article discusses the role of flavonoids in alleviating oxidative stress and inflammation, two common components of many human diseases. The results of epidemiological studies on flavonoids are also presented.

Role of natural plant extracts and hyaluronic acid derivatives in intranasal strategies for brain delivery. A review

In the last two decades, different routes of administration have been explored for the treatment of central nervous system (CNS) disorders, involving biomolecules and drugs. Among them, transmucosal route is gaining particular interest, due to its low toxicity in chronic treatments, as well as high and rapid drug absorption, making it suitable for systemic delivery of various drugs. Indeed, it allows an easy bypass of the blood-brain barrier by using the olfactory region, promoting a direct drug delivery to the brain. Despite its advantages, some side effects like nasal irritation and rapid drainage remain relevant. Recent scientific studies are focusing on the design of mucoadhesive carriers to enhance drug residence time on the mucosa and providing sustained release. Hyaluronic acid (HA) is emerging as a valid solution for nasal delivery, with potential in treating CNS disorders. The main driving idea of this narrative review is to present the state of art on gels and micro/nanoparticles based on HA functionalized with natural extracts for treating the CNS via the nasal route. Future research aims to address existing challenges to improve their formulations for effective CNS delivery.

Mild Traumatic Brain Injury Impairs Fear Extinction and Network Excitability in the Infralimbic Cortex

Traumatic brain injury (TBI) is a leading cause of morbidity and disability, with mild TBI (concussions) representing over 80% of cases. Although often considered benign, mild TBI is associated with persistent neuropsychiatric conditions, including post-traumatic stress disorder, anxiety, and depression. A hallmark of these conditions is impaired fear extinction (FE), the process by which learned fear responses are inhibited in safe contexts. This dysfunction contributes to maladaptive fear expression and is linked to altered neurocircuitry, particularly in the infralimbic cortex (IL), a key region in FE. Despite extensive evidence of impaired FE in patients with mild TBI and animal models, the specific mechanisms underlying this deficit remain poorly understood. This study aimed to address this gap by combining cued-FE behavior, local field potential recordings, and whole-cell patch-clamp techniques to investigate how mild TBI affects IL network activity and excitability in a mouse model of TBI. Our results demonstrate that mild lateral fluid percussion injury significantly impairs FE memory, as evidenced by an elevated cued-fear response during extinction testing 10 days post-injury. Field potential recordings revealed decreased activation of the IL network in both layers II/III and V, which was consistent with the observed behavioral deficits. Further analysis of synaptic physiology revealed an imbalance in excitatory and inhibitory neurotransmission (E/I imbalance) in the IL, characterized by reduced excitatory input and enhanced inhibitory input to neurons in both layers. Moreover, intrinsic excitability was altered in IL neurons after mild TBI. This study provides novel insights into how mild TBI disrupts the neurocircuitry underlying FE, specifically by suppressing IL excitability. These results highlight the importance of understanding the mechanistic disruptions in IL activity for developing therapeutic strategies to address fear-based disorders in patients with mild TBI.

Tailored Mesoporous Silica Nanoparticles and the Chick Chorioallantoic Membrane: A Promising Strategy and Model for Efficient Blood-Brain Barrier Crossing

Crossing the blood-brain barrier (BBB) remains a major challenge for brain-targeted drug delivery. Mesoporous silica nanoparticles (MSNs) with tunable size and surface properties are promising vehicles for crossing the BBB. In this study, we explored the potential applications of the chick chorioallantoic membrane (CAM) model in combination with nanotherapeutics. We synthesized ∼25 nm MSNs and RITC-conjugated MSNs (RMSNs) with short PEG chains and varying amounts of positively charged molecules, specifically tertiary amine (polyethylenimine, PEI) or quaternary amine (trimethylammonium, TA), to investigate the positive charge effects on BBB penetration. Strongly positively charged TA-modified RMSNs (s-RMSN@PEG/TA, where s denotes strongly positively charged) effectively crossed the chick embryo BBB, whereas PEI-modified RMSNs did not. Although the weakly positively charged formulation (w-MSN@PEG/TA, where w denotes weakly positively charged) exhibited higher Dox loading capacity and a faster release rate, s-MSN@PEG/TA demonstrated superior BBB penetration and drug permeability. Consistent with chick CAM results, RMSN@PEG/TA also penetrated the BBB in mice. Long-chain PEG-modified RMSN@PEG/TA (RMSN@PEG(L)/TA, where L denotes long-chain PEG) showed reduced BBB penetration due to steric hindrance, possibly shielding TA molecules. This study highlights the effectiveness of optimizing short PEG chain density and TA modification for MSN-based BBB crossing without additional biological ligands. Furthermore, the chick CAM model proves to be a valuable alternative to mouse models for assessing BBB crossing of nanoparticles, offering significant research opportunities.

The role of alarmins in neuroinflammation following spinal cord injury: A systematic review of the literature

BACKGROUND

Alarmins, or damage-associated molecular patterns (DAMPs), are a diverse class of molecules essential for cellular homeostasis; however, their activation following traumatic cell necrosis contributes to neuroinflammation leading to neurologic deficits. This review aims to highlight the current preclinical alarmin studies and define their neuroprotective role in the treatment of SCI.

METHODS

A systematic review was performed to evaluate studies investigating alarmin-mediated immune and neuroinflammatory responses following SCI in animal models. Primary outcomes investigated included immunostaining of cell lines, quantification of alarmin, cytokine, and inflammatory mediators, myelin staining, and animal function scores.

RESULTS

IL-1α, HMGB1, S100A1, MIF, D-DT, IL-33, heme, cell-free DNA, and extracellular nucleotides were found to act as alarmins in animal models of SCI. The expression of these molecules in neurons and neuroglia at the SCI lesion site increased levels of TNF-α, IL-1β, and iNOS, contributing to neuroinflammation. Induction of the neurotoxic phenotypes of macrophages, microglia, and astrocytes by IL-1α, HMGB1, and IL-33 promoted cell death and reduction in oligodendrocyte number. Inhibitors of alarmin-signaling pathways, such as toll-like receptors (TLRs), IL-1R1, RAGE, ST2, and mTOR improved neurological function, as shown by enhanced postoperative locomotion.

CONCLUSIONS

Elevated alarmin expression and activity at the SCI site contribute to functional deficits by augmenting neuroinflammation, cell death, and cytotoxic neuroglia. Targeting alarmin-mediated signaling pathways represents a promising therapeutic approach in SCI treatment.

5'-Guanidino Xylofuranosyl Nucleosides as Novel Types of 5'-Functionalized Nucleosides with Biological Potential

Background/Objectives: While various nucleoside and nucleotide analogs have been approved as anticancer and antiviral drugs, their limitations, including low bioavailability and chemotherapeutic resistance, encourage the development of novel structures. In this context, and motivated by our previous findings on bioactive 3'-O-substituted xylofuranosyl nucleosides and 5-guanidine xylofuranose derivatives, we present herein the synthesis and biological evaluation of 5'-guanidino furanosyl nucleosides comprising 6-chloropurine and uracil moieties and a 3-O-benzyl xylofuranosyl unit. Methods: The synthetic methodology was based on the N-glycosylation of a 5-azido 3-O-benzyl xylofuranosyl acetate donor with the silylated nucleobase and a subsequent one-pot sequential two-step protocol involving Staudinger reduction of the thus-obtained 5-azido uracil and N7/N9-linked purine nucleosides followed by guanidinylation with N,N'-bis(tert-butoxycarbonyl)-N''-triflylguanidine. The molecules were evaluated for their anticancer and anti-neurodegenerative diseases potential. Results: 5'-Guanidino 6-chloropurine nucleosides revealed dual anticancer and butyrylcholinesterase (BChE)-inhibitory effects. Both N9/N7-linked nucleosides exhibited mixed-type and selective submicromolar/micromolar BChE inhibiton. The N9 regioisomer was the best inhibitor (Ki/Ki' = 0.89 μM/2.96 μM), while showing low cytotoxicity to FL83B hepatocytes and no cytotoxicity to human neuroblastoma cells (SH-SY5Y). Moreover, the N9-linked nucleoside exhibited selective cytotoxicity to prostate cancer cells (DU-145; IC50 = 27.63 μM), while its N7 regioisomer was active against all cancer cells tested [DU-145, IC50 = 24.48 μM; colorectal adenocarcinoma (HCT-15, IC50 = 64.07 μM); and breast adenocarcinoma (MCF-7, IC50 = 43.67 μM)]. In turn, the 5'-guanidino uracil nucleoside displayed selective cytotoxicity to HCT-15 cells (IC50 = 76.02 μM) and also showed neuroprotective potential in a Parkinson's disease SH-SY5Y cells' damage model. The active molecules exhibited IC50 values close to or lower than those of standard drugs, and comparable, or not significant, neuro- and hepatotoxicity. Conclusions: These findings demonstrate the interest of combining guanidine moieties with nucleoside frameworks towards the search for new therapeutic agents.

Harnessing Photo-Energy Conversion in Nanomaterials for Precision Theranostics

The rapidly advancing field of theranostics aims to integrate therapeutic and diagnostic functionalities into a single platform for precision medicine, enabling the simultaneous treatment and monitoring of diseases. Photo-energy conversion-based nanomaterials have emerged as a versatile platform that utilizes the unique properties of light to activate theranostics with high spatial and temporal precision. This review provides a comprehensive overview of recent developments in photo-energy conversion using nanomaterials, highlighting their applications in disease theranostics. The discussion begins by exploring the fundamental principles of photo-energy conversion in nanomaterials, including the types of materials used and various light-triggered mechanisms, such as photoluminescence, photothermal, photoelectric, photoacoustic, photo-triggered SERS, and photodynamic processes. Following this, the review delves into the broad spectrum of applications of photo-energy conversion in nanomaterials, emphasizing their role in the diagnosis and treatment of major diseases, including cancer, neurodegenerative disorders, retinal degeneration, and osteoarthritis. Finally, the challenges and opportunities of photo-energy conversion-based technologies for precision theranostics are discussed, aiming to advance personalized medicine.

Advancing Alzheimer's disease therapy through engineered exosomal Macromolecules

Exosomes are a subject of continuous investigation due to their function as extracellular vesicles (EVs) that significantly contribute to the pathophysiology of certain neurodegenerative disorders (NDD), including Alzheimer's disease (AD). Exosomes have shown the potential to carry both therapeutic and pathogenic materials; hence, researchers have used exosomes for medication delivery applications. Exosomes have reduced immunogenicity when used as natural drug delivery vehicles. This guarantees the efficient delivery of the medication without causing significant side reactions. Exosomes have lately enabled the potential for drug delivery in AD, along with promising future therapeutic uses for the detection of neurodegenerative disorders. Furthermore, exosomes have been examined for their prospective use in illness diagnosis and prediction before the manifestation of symptoms. This review will document prior studies and will concentrate on the rationale behind the substantial potential of exosomes in the treatment of AD and their prospective use as a diagnostic and predictive tool for this condition.

Pharmacological effects and pharmacokinetics of the novel synthetic cathinone α-pyrrolidinoisohexanophenone (α-PiHP) compared with α-pyrrolidinovalerophenone (α-PVP) in mice

α-Pyrrolidinoisohexanophenone (α-PiHP) is a novel pyrovalerone cathinone that was among the top five synthetic cathinones seized by weight across Europe in 2022. Since α-PiHP was first reported to the European Union Drugs Agency in December 2016, its use has been linked to severe poisonings and fatalities. The present study employed in vitro and in vivo methods to evaluate the pharmacological effects and pharmacokinetics of α-PiHP in mice, using α-pyrrolidinovalerophenone (α-PVP) as a comparator drug. Our findings show that α-PiHP is a highly potent inhibitor of dopamine (DA) and norepinephrine (NE) reuptake, with a potency equivalent to that of α-PVP for the DA transporter (DAT) and slightly lower for the NE transporter (NET). The strong and targeted inhibition of DAT and NET indicates that α-PiHP has a high potential for misuse. In vivo studies showed that both drugs induced a significant increase in body temperature compared to the control, however, higher doses of α-PiHP (ED50: 4.0 mg/kg) were required to elicit locomotor activity compared to α-PVP (ED50: 1.1 mg/kg). Pharmacokinetic analyses revealed that α-PiHP reached approximately 40 % lower Cmax levels in blood and brain, which could explain the lower potency of α-PiHP in inducing locomotor activity. Overall, these findings highlight the need to evaluate the pharmacological characteristics of evolving synthetic cathinones, such as α-PiHP, to better understand the associated health risks.

Retinal macular morphology and cognitive functions in unmedicated first-episode psychosis patients

BACKGROUND

This study investigates retinal macular abnormalities and neurocognitive function, including facial emotion recognition, in individuals with unmedicated First-Episode Psychosis (FEP). The primary aim is to compare retinal morphology in FEP patients and healthy controls and examine correlations with cognitive performance.

METHOD

Thirty-two FEP patients (aged 18-45) and 30 healthy controls underwent psychiatric assessment and retinal examination using the Spectral Domain - Optical Coherence Tomography (SD-OCT), with a focus on macula. Facial emotion recognition was evaluated using the Mandal emotion recognition test for four emotions (Sad, Anger, Happy, Fear). Visual memory and executive function were assessed using the Rey-Osterrieth Complex Figure Test and the Trail Making Test, respectively. Statistical analyses included t-test, correlation analysis, and linear discriminant function analysis.

RESULTS

FEP patients showed significant macular abnormalities, with reduced thickness in multiple quadrants. Facial emotion recognition scores were notably lower among patients for all emotions tested. Patients also showed visual memory deficits. Across the three measures there were significant correlations. Discriminant function analysis indicated that a combination of emotion recognition scores and inner nasal quadrant macular thickness of left eye could effectively differentiate patients from healthy controls with high accuracy (85.5 %).

CONCLUSION

Our study demonstrates significant macular abnormalities, impaired facial emotion recognition, and visual memory deficits in patients with unmedicated FEP. These findings suggest potential of retinal abnormalities as biomarkers for psychosis. Future research with larger sample sizes could further establish retinal changes and facial emotion recognition as potential biomarkers.

microRNAs as molecular tools for brain health: Neuroprotective potential in neurodegenerative disorders

As research on microRNAs (miRNAs) advances, it is becoming increasingly clear that these small molecules play crucial roles in the central nervous system (CNS). They are involved in various essential neuronal functions, with specific miRNAs preferentially expressed in different cell types within the nervous system. Notably, certain miRNAs are found at higher levels in the brain and spinal cord compared to other tissues, suggesting they may have specialized functions in the CNS. miRNAs associated with long-term neurodegenerative changes could serve as valuable tools for early treatment decisions and disease monitoring. The significance of miRNAs such as miR-320, miR-146 and miR-29 in the early diagnosis of neurodegenerative disorders becomes evident, especially considering that many neurological and physical symptoms manifest only after substantial degeneration of specific neurons. Interestingly, serum miRNA levels such as miR-92 and miR-486 may correlate with various MRI parameters in multiple sclerosis. Targeting miRNAs using antisense strategies, such as antisense miR-146 and miR-485, may provide advantages over targeting mRNAs, as a single anti-miRNA can regulate multiple disease-related genes. In the future, anti-miRNA-based therapeutic approaches could be integrated into the clinical management of neurological diseases. Certain miRNAs, including miR-223, miR-106, miR-181, and miR-146, contribute to the pathogenesis of various neurodegenerative diseases and thus warrant greater attention. This knowledge could pave the way for the identification of new diagnostic, prognostic, and theranostic biomarkers, and potentially guiding the development of RNA-based therapeutic strategies. This review highlights recent research on the roles of miRNAs in the nervous system, particularly their protective functions in neurodegenerative disorders.

Differential memory enrichment of cytotoxic CD4 T cells in Parkinson's disease patients reactive to α-synuclein

Parkinson's disease (PD) is a complex neurodegenerative disease with a largely unknown etiology. Although the loss of dopaminergic neurons in the substantia nigra pars compacta is the pathological hallmark of PD, neuroinflammation also plays a fundamental role in PD pathology. We have previously reported that PD patients have increased frequencies of T cells reactive to peptides from α-synuclein (α-syn). However, not all PD participants respond to α-syn. Furthermore, we have previously found that CD4 T cells from PD participants responding to α-syn (PD_R) are transcriptionally distinct from PD participants not responding to α-syn (PD_NR). To gain further insight into the pathology of PD_R participants, we investigated surface protein expression of 11 proteins whose genes had previously been found to be differentially expressed when comparing PD_R and healthy control participants not responding to α-syn (HC_NR). We found that Cadherin EGF LAG seven-pass G-type receptor 2 (CELSR2) was expressed on a significantly higher proportion of CD4 effector memory T cells (TEM) in PD_R compared to HC_NR. Single-cell RNA sequencing analysis of cells expressing or not expressing CELSR2 revealed that PD_R participants have elevated frequencies of activated TEM subsets and an almost complete loss of cytotoxic TEM cells. Flow cytometry analyses confirmed that Granulysin+ CD4 cytotoxic TEM cells are reduced in PD_R. Taken together, these results provide further insight into the perturbation of T cell subsets in PD_R, and highlights the need for further investigation into the role of Granulysin+ CD4 cytotoxic TEM in PD pathology.

MEK1/2 inhibitors suppress pathological α-synuclein and neurotoxicity in cell models and a humanized mouse model of Parkinson's disease

The abnormal accumulation of misfolded proteins is a common hallmark of many neurodegenerative disorders. Among these proteins, α-synuclein (αsyn) is a well-characterized pathogenic protein in Parkinson's disease (PD) and other synucleinopathies. αsyn can be hyperphosphorylated and form pathological aggregates, leading to neurodegeneration. Thus, chemical modulators of pathological αsyn may suppress its downstream toxicity and provide entry points to therapeutic intervention. Here, we identified mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitors as negative modulators of basal αsyn in wild-type cells and that pathological αsyn in αsyn preformed fibrils (αsyn-PFF) induced the neuroblastoma cell line SHSY-5Y, PC12 cells, and primary cultured neurons. We further demonstrated that these inhibitors suppressed Ser129 phosphorylated αsyn (p-αsyn) through the kinase PLK2 downstream of MEK1/2-ERK2 in PD cell models. We established a humanized PD mouse model by injecting human αsyn-PFF into mice with homozygous knock-in of human SNCA. Oral administration of blood-brain barrier-penetrable MEK1/2 inhibitors lowered pathological αsyn and rescued PD-relevant phenotypes with an acceptable safety profile in these mice. Collectively, these data highlight MEK1/2 inhibitors as a potential therapeutic strategy for PD.

Photobiomodulation Promotes Early Recovery of Olfactory Function and Modulates Neuroprotective Gene Expression in a Mouse Model of Ischemic Stroke

Ischemic stroke often leads to neurological deficits, including olfactory dysfunction, which can significantly diminish quality of life. Photobiomodulation (PBM) has emerged as a promising therapeutic strategy for enhancing post-stroke recovery, although the molecular mechanisms, particularly regarding gene expression change, are not yet fully understood. This study investigates the long-term effects of photothrombosis (PT) on olfactory function and the olfactory bulb (OB) microenvironment, with a focus on PBM's efficacy during both early and late phases. In a mouse OB PT stroke model, PBM therapy (808-nm laser, 40 J/cm2 fluence, 325 mW/cm2, 2 min daily) was applied from day 2 to day 7 post-PT. Olfactory function was monitored from pre-stroke through day 28 using the buried food test (BFT), and MRI scans were performed on days 7 and 28 to assess tissue damage. RNA sequencing (RNA-seq) and reverse transcription quantitative PCR (RT-qPCR) were conducted on day 7 to evaluate gene expression changes, with additional RT-qPCR analyses performed on day 28. PBM significantly accelerated olfactory function recovery by day 14, with full recovery maintained through day 28. Despite functional recovery, MRI results indicated persistent infarction at 28 days. RNA-seq identified upregulation of neuroprotective genes, including Gpr39 and Or4m1, following PBM treatment, suggesting enhanced gene expression related to acute-phase recovery. However, the impact of PBM on gene expression and functional recovery appeared to wane in the later stages of recovery. These findings underscore PBM's potential to enhance early-stage recovery in ischemic stroke, though its benefits may be more limited in the chronic phase.

Diagnostics of brain tumor in the early stage: current status and future perspectives

Early diagnosis of brain tumors is challenging due to their complexity and delicate structure. Conventional imaging techniques like MRI, CT, and PET are unable to provide detailed visualization of early-stage brain tumors. Early-stage detection of brain tumors is vital for enhancing patient outcomes and survival rates. So far, several scientists have dedicated their efforts to innovating advanced diagnostic probes to efficiently cross the BBB and selectively target brain tumors for optimal imaging. The integration of these techniques presents a viable pathway for non-invasive, accurate, and early-stage tumor identification. Herein, we provide a timely update on the various imaging probes and potential challenges for the diagnosis of early-stage brain tumors. Furthermore, this review highlights the significance of integrating advanced imaging probes for improving the early detection of brain tumors, ultimately enhancing treatment outcomes. Hopefully, this review will stimulate the interest of researchers to accelerate the development of new imaging probes and even their clinical translation for improving the early diagnosis of brain tumors.

Augmented and Programmatically Optimized LLM Prompts Reduce Chemical Hallucinations

Utilizing large Language models (LLMs) for handling scientific information comes with risk of the outputs not matching expectations, commonly called hallucinations. To fully utilize LLMs in research requires improving their accuracy, avoiding hallucinations, and extending their scope to research topics outside their direct training. There is also a benefit to getting the most accurate information from an LLM at the time of inference without having to create and train custom new models for each application. Here, augmented generation and machine learning-driven prompt optimization are combined to extract performance improvements over base LLM function on a common chemical research task. Specifically, an LLM was used to predict the topological polar surface area (TPSA) of molecules. By using augmented generation and machine learning-optimized prompts, the error in the prediction was reduced to 11.76 root-mean-squared error (RMSE) from 62.34 RMSE with direct calls to the same LLM.

A minimally invasive thrombotic model to study stroke in awake mice

Experimental stroke models in rodents are essential for mechanistic studies and therapeutic development. However, these models have several limitations negatively impacting their translational relevance. Here we aimed to develop a minimally invasive thrombotic stroke model through magnetic particle delivery that does not require craniotomy, is amenable to reperfusion therapy, can be combined with in vivo imaging modalities, and can be performed in awake mice. We found that the model results in reproducible cortical infarcts within the middle cerebral artery (MCA) territory with cytologic and immune changes similar to that observed with more invasive distal MCA occlusion models. Importantly, the injury produced by the model was ameliorated by tissue plasminogen activator (tPA) administration. We also show that MCA occlusion in awake animals results in bigger ischemic lesions independent of day/night cycle. Magnetic particle delivery had no overt effects on physiologic parameters and systemic immune biomarkers. In conclusion, we developed a novel stroke model in mice that fulfills many requirements for modeling human stroke.

Intracerebral delivery of the ionic liquid form of edaravone via nose-to-brain delivery route for treating cerebral ischemia/reperfusion injury

Nose-to-brain drug delivery via intranasal administration is expected to be a promising route for efficient delivery to the central nervous system (CNS), as it allows for noninvasive and direct delivery of drugs to the CNS by avoiding the blood-brain barrier. However, the delivery efficiency of the administered drugs is still limited owing to poor mucosal epithelium permeation and mucociliary clearance. The use of ionic liquids (ILs) has garnered substantial attention in biomedical engineering for their potential to improve the physicochemical properties of active pharmaceutical ingredients and overcome biological barriers that impede drug delivery to the desired sites. We hypothesized that ILs are promising delivery platforms for achieving efficient permeation through the mucosal epithelium for nose-to-brain delivery. Herein, we newly developed IL forms of edaravone (edaravone-ILs), a clinically used cerebroprotectant, and applied them to nose-to-brain delivery to treat cerebral ischemia/reperfusion (I/R) injury. Through a series of in vitro studies, we found the biocompatible edaravone-IL which exhibits superior antioxidant activity and enhanced water solubility compared to that with native edaravone. Following intranasal administration, edaravone delivery to the brain was significantly more efficient with edaravone-IL than that with the edaravone solution. Moreover, the intranasal administration of edaravone-IL significantly ameliorated cerebral I/R injury in transient middle cerebral artery-occluded rats. These findings suggest that ILs offer a promising way for efficient intracerebral drug delivery via the nose-to-brain route and edaravone-IL could serve as a potential cerebroprotective agent for treating cerebral I/R injury.

Enhanced Cytotoxicity and Receptor Modulation by SMA-WIN 55,212-2 Micelles in Glioblastoma Cells

Glioblastoma (GBM), a devastating brain malignancy, resists conventional therapies due to molecular heterogeneity and the blood-brain barrier's significant restriction on drug delivery. Cannabinoids like WIN 55,212-2 show promise but are limited by poor solubility and systemic toxicity. To address these challenges, we evaluated styrene-maleic acid (SMA) micellar encapsulation of WIN 55,212-2 (SMA-WIN) against free WIN in epithelial (LN18) and mesenchymal (A172) GBM cell lines, targeting cytotoxicity and receptor modulation (CB1, CB2, TRPV1, PPAR-γ). SMA-WIN exhibited significantly enhanced cytotoxicity, achieving IC50 values of 12.48 µM (LN18) and 16.72 µM (A172) compared to 20.97 µM and 30.9 µM for free WIN, suggesting improved cellular uptake via micellar delivery. In LN18 cells, both formulations upregulated CB1 and CB2, promoting apoptosis. Notably, SMA-WIN uniquely increased PPAR-γ expression by 2.3-fold in A172 cells, revealing a mesenchymal-specific mechanism absent in free WIN, which primarily modulated CB1/CB2. These findings position SMA-WIN as a promising candidate for precision GBM therapy, particularly for resistant mesenchymal subtypes, paving the way for in vivo validation to confirm blood-brain barrier penetration and clinical translation.