GV-971 attenuates α-Synuclein aggregation and related pathology

Biology, Pathology, and Targeted Therapy of Exosomal Cargoes in Parkinson's Disease: Advances and Challenges

Parkinson's disease (PD) involves the loss of dopamine neurons and accumulation of alpha-synuclein (α-syn), leading to Lewy bodies. While α-syn-targeting immunotherapies show promise, clinical application is challenging. Emerging strategies include nano-platforms for targeted delivery and imaging, and cell-based therapies with patient-specific dopaminergic neurons, aiming to enhance treatment effectiveness despite challenges. Exosome-based methodologies are emerging as a promising area of research in PD due to their role in the spread of α-syn pathology. Exosomes are small extracellular vesicles that can carry misfolded α-syn and transfer it between cells, contributing to the progression of PD. They can be isolated from biological fluids such as blood and cerebrospinal fluid, making them valuable biomarkers for the disease. Additionally, engineering exosomes to deliver therapeutic agents, including small molecules, RNA, or proteins, offers a novel approach for targeted therapy, capitalizing on their natural ability to cross the blood-brain barrier (BBB). Ongoing studies are evaluating the safety and efficacy of these engineered exosomes in clinical settings. This review explores the role of exosomes in PD, focusing on their potential for diagnosis, treatment, and understanding of pathology. It highlights advancements and future directions in using exosomes as biomarkers and therapeutic tools.

Protective effects of wogonin in the treatment of central nervous system and degenerative diseases

Wogonin, an O-methylated flavonoid extracted from Scutellaria baicalensis, has demonstrated profound neuroprotective effects in a range of central nervous system (CNS) diseases. This review elucidates the pharmacological mechanisms underlying the protective effects of wogonin in CNS diseases, including ischemic stroke, hemorrhagic stroke, traumatic brain injury, epilepsy, anxiety, neurodegenerative diseases, and CNS infections. Wogonin modulates key signaling pathways, such as the MAPK, NF-κB, and ROS pathways, contributing to its anti-inflammatory, antioxidant, and antiapoptotic properties. In ischemic stroke models, wogonin reduces infarct size and enhances neurological outcomes by mitigating inflammation and oxidative stress. For patients with hemorrhagic stroke and traumatic brain injury, it accelerates hematoma regression, mitigates secondary brain damage, and promotes neurogenesis, making it an entirely new treatment option for patients with limited access to this type of therapy. Its anticonvulsant and anxiolytic effects are mediated through GABA-A receptor modulation. Moreover, wogonin shows promise in treating neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease by promoting autophagy and reducing neuroinflammation. Additionally, it exhibits antiviral properties, offering potential benefits against CNS infections. Despite extensive preclinical evidence, further clinical studies are warranted to confirm its efficacy and safety in humans. This review highlights the great therapeutic potential of wogonin in terms of CNS protection. However, despite the substantial preclinical evidence, further large-scale clinical studies are necessary. Future researchers need to further explore the long-term efficacy and safety of wogonin in clinical trials and translate it for early application in the clinical treatment of true CNS disorders.

Radiation-Induced Brain Injury: Mechanistic Insights and the Promise of Gut-Brain Axis Therapies

Radiation therapy is widely recognized as an efficacious modality for treating neoplasms located within the craniofacial region. Nevertheless, this approach is not devoid of risks, predominantly concerning potential harm to the neural structures. Adverse effects may encompass focal cerebral necrosis, cognitive function compromise, cerebrovascular pathology, spinal cord injury, and detriment to the neural fibers constituting the brachial plexus. With increasing survival rates among oncology patients, evaluating post-treatment quality of life has become crucial in assessing the benefits of radiation therapy. Consequently, it is imperative to investigate therapeutic strategies to mitigate cerebral complications from radiation exposure. Current management of radiation-induced cerebral damage involves corticosteroids and bevacizumab, with preclinical research on antioxidants and thalidomide. Despite these efforts, an optimal treatment remains elusive. Recent studies suggest the gut microbiota's involvement in neurologic pathologies. This review aims to discuss the causes and existing treatments for radiation-induced cerebral injury and explore gut microbiota modulation as a potential therapeutic strategy.

Small molecule modulators of alpha-synuclein aggregation and toxicity: Pioneering an emerging arsenal against Parkinson's disease

Parkinson's disease (PD) is primarily characterized by loss of dopaminergic neurons in the substantia nigra pars compacta region of the brain and accumulation of aggregated forms of alpha-synuclein (α-Syn), an intrinsically disordered protein, in the form of Lewy Bodies and Lewy Neurites. Substantial evidences point to the aggregated/fibrillar forms of α-Syn as a central event in PD pathogenesis, underscoring the modulation of α-Syn aggregation as a promising strategy for PD treatment. Consequently, numerous anti-aggregation agents, spanning from small molecules to polymers, have been scrutinized for their potential to mitigate α-Syn aggregation and its associated toxicity. Among these, small molecule modulators like osmoprotectants, polyphenols, cellular metabolites, metals, and peptides have emerged as promising candidates with significant potential in PD management. This article offers a comprehensive overview of the effects of these small molecule modulators on the aggregation propensity and associated toxicity of α-Syn and its PD-associated mutants. It serves as a valuable resource for identifying and developing potent, non-invasive, non-toxic, and highly specific small molecule-based therapeutic arsenal for combating PD. Additionally, it raises pertinent questions aimed at guiding future research endeavours in the field of α-Syn aggregation remodelling.

The Brain-Gut-Bone Axis in Neurodegenerative Diseases: Insights, Challenges, and Future Prospects

Neurodegenerative diseases are global health challenges characterized by the progressive degeneration of nerve cells, leading to cognitive and motor impairments. The brain-gut-bone axis, a complex network that modulates multiple physiological systems, has gained increasing attention owing to its profound effects on the occurrence and development of neurodegenerative diseases. No comprehensive review has been conducted to clarify the triangular relationship involving the brain-gut-bone axis and its potential for innovative therapies for neurodegenerative disorders. In light of this, a new perspective is aimed to propose on the interplay between the brain, gut, and bone systems, highlighting the potential of their dynamic communication in neurodegenerative diseases, as they modulate multiple physiological systems, including the nervous, immune, endocrine, and metabolic systems. Therapeutic strategies for maintaining the balance of the axis, including brain health regulation, intestinal microbiota regulation, and improving skeletal health, are also explored. The intricate physiological interactions within the brain-gut-bone axis pose a challenge in the development of effective treatments that can comprehensively target this system. Furthermore, the safety of these treatments requires further evaluation. This review offers a novel insights and strategies for the prevention and treatment of neurodegenerative diseases, which have important implications for clinical practice and patient well-being.

GV-971 attenuates the progression of neuromyelitis optica in murine models and reverses alterations in gut microbiota and associated peripheral abnormalities

AIMS

Growing evidence suggests that an imbalanced gut microbiota composition plays a crucial role in the development of neuromyelitis optica spectrum disorders (NMOSD), an inflammatory demyelinating disease primarily affecting the optic nerves and central nervous system (CNS). In light of this, we explored the potential therapeutic benefits of GV-971 in NMOSD. GV-971 is a drug used for treating mild-to-moderate Alzheimer's disease, which targets the gut-brain axis and reduces neuroinflammation.

METHODS

To evaluate GV-971's effects, we employed the experimental autoimmune encephalomyelitis (EAE) mouse model to establish NMOSD animal models. This was achieved by injecting NMO-IgG into aged mice (11 months old) or using NMO-IgG along with complement injection and microbubble-enhanced low-frequency ultrasound (MELFUS) techniques in young mice (7 weeks old). We assessed the impact of GV-971 on incidence rate, clinical scores, body weight, and survival, with methylprednisolone serving as a positive control. In NMOSD models of young mice, we analyzed spinal cord samples through H&E staining, immunohistochemistry, and Luxol Fast Blue staining. Fecal samples collected at different time points underwent 16S rRNA gene sequencing, while plasma samples were analyzed using cytokine array and untargeted metabolomics analysis.

RESULTS

Our findings indicated that GV-971 significantly reduced the incidence of NMOSD, alleviated symptoms, and prolonged survival in NMOSD mouse models. The NMOSD model exhibited substantial neuroinflammation and injury, accompanied by imbalances in gut microbiota, peripheral inflammation, and metabolic disorders, suggesting a potentially vicious cycle that accelerates disease pathogenesis. Notably, GV-971 effectively reduces neuroinflammation and injury, and restores gut microbiota composition, as well as ameliorates peripheral inflammation and metabolic disorders.

CONCLUSIONS

GV-971 attenuates the progression of NMOSD in murine models and reduces neuroinflammation and injury, likely through its effects on remodeling gut microbiota and peripheral inflammation and metabolic disorders.

GV-971 attenuates α-Synuclein aggregation and related pathology

RATIONALE

Synucleinopathies, including Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB), share a distinct pathological feature, that is, a widespread accumulation of α-synuclein (α-syn) in the brain. There is a significant clinical unmet need for disease-modifying treatments for synucleinopathies. Recently, a seaweed-derived mixture of oligosaccharides sodium oligomannate, GV-971, was approved for Phase 2 clinical trials for PD. This study aimed to further evaluate the therapeutic effects of GV-971 on synucleinopathies using cellular and animal models and explore its associated molecular mechanisms.

METHODS

α-Syn aggregation was assessed, in vitro and ex vivo, by ThT assay. A dopaminergic neuron cell line, Prnp-SNCAA53T mice, and brain slices from PD and DLB patients were used to determine the efficacy of GV-971 in ameliorating α-syn pathology. Measurements of motor functions, including pole, cylinder, and rotarod tests, were conducted on Prnp-SNCAA53T mice 4 weeks after intragastric administration of GV-971 (200 mg day-1  kg-1 ).

RESULTS

GV-971 effectively prevented α-syn aggregation and even disassembled pre-aggregated α-syn fibrils, in vitro and ex vivo. In addition, GV-971 was able to rescue α-syn-induced neuronal damage and reduced release of extracellular vesicles (EVs), likely via modulating Alix expression. In the Prnp-SNCAA53T mouse model, when treated at the age of 5 months, GV-971 significantly decreased α-syn deposition in the cortex, midbrain, and cerebellum regions, along with ameliorating the motor dysfunctions.

CONCLUSIONS

Our results indicate that GV-971, when administered at a relatively early stage of the disease process, significantly reduced α-syn accumulation and aggregation in Prnp-SNCAA53T mice. Furthermore, GV-971 corrected α-syn-induced inhibition of EVs release in neurons, contributing to neuronal protection. Future studies are needed to further assess GV-971 as a promising disease-modifying therapy for PD and other synucleinopathies.

Machine learning in Alzheimer's disease drug discovery and target identification

Alzheimer's disease (AD) stands as a formidable neurodegenerative ailment that poses a substantial threat to the elderly population, with no known curative or disease-slowing drugs in existence. Among the vital and time-consuming stages in the drug discovery process, disease modeling and target identification hold particular significance. Disease modeling allows for a deeper comprehension of disease progression mechanisms and potential therapeutic avenues. On the other hand, target identification serves as the foundational step in drug development, exerting a profound influence on all subsequent phases and ultimately determining the success rate of drug development endeavors. Machine learning (ML) techniques have ushered in transformative breakthroughs in the realm of target discovery. Leveraging the strengths of large dataset analysis, multifaceted data processing, and the exploration of intricate biological mechanisms, ML has become instrumental in the quest for effective AD treatments. In this comprehensive review, we offer an account of how ML methodologies are being deployed in the pursuit of drug discovery for AD. Furthermore, we provide an overview of the utilization of ML in uncovering potential intervention strategies and prospective therapeutic targets for AD. Finally, we discuss the principal challenges and limitations currently faced by these approaches. We also explore the avenues for future research that hold promise in addressing these challenges.