Parkinson's disease treatment: past, present, and future

NGF regulates survival and differentiation of umbilical mesenchymal stem/stromal cells into GABAergic, dopaminergic and cholinergic lineages

Mesenchymal stem cells advantageous properties have led scientists to conduct trials on a range of medical conditions, including incurable neurodegenerative diseases. Wharton-Jelly derived mesenchymal stem cells, given their ease of collection, are frequently selected for these studies. This research aimed to investigate the effects of nerve growth factor (NGF) gene overexpression on the neural differentiation, survivability, and gene and protein expression of these cells. The level of gene expression was tested using the ddPCR method. Six umbilical cords from donors were collected, and three randomly chosen primary cultures of Wharton-Jelly derived mesenchymal stem cells were used in experiment. Cells were transduced with lentiviral vectors and underwent a 12-day differentiation process. The results revealed neuron-like cells with significantly high expression of CHAT, GAD2 and TH genes. A corresponding increase in protein expression was also observed. Immunostaining demonstrated notable differences in neuron-like phenotypes, contingent on the environmental conditions of the research groups. Throughout the experiment, samples with transduced mesenchymal stem cells overexpressing the NGF gene showed the highest expression levels from almost all of studied genes and proteins, and were also the most phenotypically similar to neuron-like cells. The study concluded that sustained overexpression of NGF: guides mesenchymal stem cells towards the neural pathway, facilitates the differentiation of modified mesenchymal stem cells into GABAergic, dopaminergic, and cholinergic neuron-like cells, suggests that GABAergic neurons' marker predominantly co-expresses with other neurons' markers, such as cholinergic or dopaminergic ones, increases survivability of modified mesenchymal stem cells in toxic conditions; The limitations of the study is that we merely know that cells have begun to express neurogenic markers, but in the absence of standards for mature neuronal markers, we do not yet know how far they have progressed as differentiating cells.

The relationship between Parkinson's disease and sexual hyperactivity secondary to drug treatment: A systematic review

INTRODUCTION

This review addresses the prevalence of hypersexual behavior in Parkinson's patients and the underlying neurobiological mechanisms, identifying risk and protective factors, comparing incidence among different treatments, and proposing recommendations for management and prevention.

OBJECTIVE

To conduct a review on the relationship between Parkinson's disease and hypersexual behavior as a result of pharmacological treatment.

METHODOLOGY

The search strategy, guided by PRISMA and PICOS criteria, focuses on the correlation between Parkinson's disease and hypersexual behavior due to pharmacological treatment. Utilizing databases like PubMed and Proquest, studies from the last 10 years in English or Spanish were selected, emphasizing clinical trials with Parkinson's patients under treatment. Inaccessible, irrelevant, or mixed-sample studies were excluded. The Cochrane Scale assessed the risk of bias.

RESULTS

Out of 122 records, 103 remained after eliminating duplicates; 48 were reviewed, and ultimately, 6 studies met the inclusion criteria for analysis.

CONCLUSIONS

Synthesizing the risk and protective factors linked to hypersexual behavior in Parkinson's patients receiving pharmacological treatment underscores the critical need for early detection and incorporation of these factors into clinical care. The suggested guidelines for managing and preventing hypersexual behavior in these patients carry substantial practical implications.

Management of freezing of gait - mechanism-based practical recommendations

Freezing of gait (FOG) is a debilitating motor symptom that commonly occurs in Parkinson disease, atypical parkinsonism and other neurodegenerative conditions. Management of FOG is complex and requires a multifaceted approach that includes pharmacological, surgical and non-pharmacological interventions. In this Expert Recommendation, we provide state-of-the-art practical recommendations for the management of FOG, based on the latest insights into the pathophysiology of the condition. We propose two complementary treatment flows, both of which are linked to the pathophysiology and tailored to specific FOG phenotypes. The first workflow focuses on the reduction of excessive inhibitory outflow from the basal ganglia through use of dopaminergic medication or advanced therapies such as deep brain stimulation and infusion therapy. The second workflow focuses on facilitation of processing across cerebral compensatory networks by use of non-pharmacological interventions. We also highlight interventions that have potential for FOG but are not supported by sufficient evidence to recommend for clinical application. Our updated recommendations are intended to enable effective symptomatic relief once FOG has developed, but we also consider potential targets for preventive approaches. The recommendations are based on scientific evidence where available, supplemented with practice-based evidence informed by our clinical experience.

Volatile oils of Schisandra chinensis (Turcz.) Baill alleviates Parkinson's disease by activating the Nrf2 pathway to positively regulate autophagy and oxidative stress

Schisandra chinensis (Turcz.) Baill, which is frequently used in health products and drinks, is recognized for its high content of essential oils that could have protective effects against PD, despite the lack of complete understanding of its pharmacological mechanisms. This research aims to examine how ESC can affect autophagy signaling pathways and activate the Nrf2/HO-1 pathway to effectively decrease oxidative damage, thus shedding light on the possible anti-PD effects of this treatment. The results demonstrated that ESC significantly reduced behavioral issues linked to Parkinson's disease in a mouse model that was induced by MPTP and safeguarded dopaminergic neurons that expressed tyrosine hydroxylase. Moreover, ESC boosted the antioxidant capability of Nrf2, assisted with autophagy processes, and finally decreased protein expression levels of Keap1, HO-1, MAPK, mTOR, and ERK. According to in vitro studies, ESC treatment had a significant reduction in H2O2-induced cytotoxicity and oxidative stress levels, which suggests that Nrf2 targets ESC after treatment. The activation of both autophagy and Nrf2 antioxidant pathways was assessed using western blotting. In conclusion, ESC exhibits the potential to suppress oxidative stress by activating Nrf2 in response to autophagy, which is positioned as a promising pharmaceutical candidate, especially for the management and treatment of PD and related disorders.

Corydaline Alleviates 1-Methyl-4-Phenylpyridium (MPP+)-Induced Human Neuroblastoma Cell Injury by BAP1-NRF2/HO-1/GPX4 Pathway

Corydaline (Cory) is a naturally extracted acetylcholinesterase inhibitor. In this study, we aimed to explore the possible roles and functions in Parkinson's disease (PD) using 1-methyl-4-phenylpyridium (MPP+)-induced human neuroblastoma SK-N-SH cells. SK-N-SH cells were treated with MPP+ to mimic PD in vitro model. MTT assay and EdU assay were conducted to evaluate cell proliferation. Flow cytometry analysis was performed to analyze cell apoptosis. ELISA kits were adopted to examine the concentrations of inflammatory factors. Ferroptosis-related markers were determined by related commercial kits. qRT-PCR and western blot were utilized to measure the expression of BRCA1-associated protein 1 (BAP1). MPP+ treatment repressed the proliferation and promoted the apoptosis, inflammation and ferroptosis in SK-N-SH cells. Cory alleviated MPP+-induced damage of SK-N-SH cells. BAP1 level was induced by MPP+ in SK-N-SH cells, while Cory treatment relieved the effect. Moreover, Cory ameliorated MPP+-induced SK-N-SH cell injury by altering BAP1 expression. Additionally, we demonstrated that Cory regulated NRF2, HO-1 and GPX4 expression in MPP+-treated SK-N-SH cells through BAP1. Cory alleviated MPP+-induced human neuroblastoma cell injury by modulating BAP1-NRF2/HO-1/GPX4 pathway, which might provide a novel regulatory axis in PD development.

m6A Demethylase FTO-Mediated Upregulation of BAP1 Induces Neuronal Ferroptosis via the p53/SLC7A11 Axis in the MPP+/MPTP-Induced Parkinson's Disease Model

Background: Parkinson's disease (PD) is a neurodegenerative disorder characterized by the involvement of ferroptosis in its pathological mechanism. In this study, the effects and mechanism of BRCA1-associated protein 1 (BAP1) on neuronal ferroptosis in PD were evaluated. Methods: A PD mouse model was constructed by injecting mice with MPTP. Nissl staining, immunohistochemistry, immunofluorescence, and Prussian blue staining evaluated histopathology and iron distribution. The PD cell model was constructed by subjecting SK-N-SH cells to MPP+. The m6A level of BAP1 was assessed by MeRIP. mRNA levels of BAP1, FTO, IGF2BP1, METTL3, YTHDF2, and SLC7A11 were evaluated utilizing RT-qPCR. Protein levels of BAP1, FTO, IGF2BP1, METTL3, YTHDF2, SLC7A11, and p53 were measured by Western blot. Cell viability was assessed using CCK-8 assay, and TUNEL was used for assessing apoptosis. The levels of MDA, GSH, SOD, and Fe2+ were also measured. The interactions among molecules were verified using RIP assay, dual luciferase reporter assay, and ChIP assay. Results: SK-N-SH cells treated with MPP+ showed a decrease in overall m6A levels of BAP1. FTO facilitated m6A demethylation of BAP1, leading to an increased level of expression of BAP1. m6A-binding protein, YTHDF2 recognized and decayed methylated mRNA of BAP1, leading to the reduced BAP1 stability. The FTO/BAP1 axis promoted MPP+-induced ferroptosis by suppressing SLC7A11. BAP1, in collaboration with p53, reduced the level of expression of SLC7A11. Knocking down BAP1 mitigated ferroptosis in an MPTP mouse model. Conclusion: m6A-mediated modification of BAP1 regulates neuronal ferroptosis by cooperating with p53 to decrease the level of SLC7A11. Thus, BAP1 may be a potential therapeutic target for PD treatment.

Roles of SIRT3 in cardiovascular and neurodegenerative diseases

Sirtuin-3 (SIRT3) in mitochondria has nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase activity. As such, SIRT3 is crucial in cardiovascular and neurodegenerative diseases. Advanced proteomics and transcriptomics studies have revealed that SIRT3 expression becomes altered when the heart or brain is affected by external stimuli or disease, such as diabetic cardiomyopathy, atherosclerosis, myocardial infarction, Alzheimer's disease, Huntington's disease, and Parkinson's disease. More specifically, SIRT3 participates in the development of these disorders through its deacetylase activity and in combination with downstream signaling pathways. The paper reviews SIRT3's expression changes, roles, and mechanisms associated with the development of cardiovascular and neurodegenerative diseases. Additionally, strategies targeting SIRT3 to treat or regulate cardiovascular and neurodegenerative disease development are discussed.

Potential Biomarkers and Treatment of Neuroinflammation in Parkinson's Disease

Parkinson's disease (PD) is a degenerative disease of the central nervous system primarily affecting middle-aged and elderly individuals, significantly compromising their quality of life. Neuroinflammation is now recognized as a key feature in the pathogenesis of PD. This study reviews recent advances in the identification of potential biomarkers associated with neuroinflammation in PD and their significance for therapeutic strategies. These findings suggest that inflammatory factors play a pivotal role in PD treatment, and interventions involving anti-inflammatory drugs, physical exercise, and dietary modifications have shown promising results in mitigating disease progression.

The Role of Virtual Reality in Postural Rehabilitation for Patients with Parkinson's Disease: A Scoping Review

Parkinson's disease is the second most common neurodegenerative disease worldwide, characterized by bradykinesia, rigidity, tremor, and postural instability. These symptoms often lead to significant postural deformities and an increased risk of falls, severely impacting the quality of life. Conventional rehabilitation methods have shown benefits, but recent advancements suggest that virtual reality (VR) could offer a promising alternative. This scoping review aims to analyze the current literature to evaluate the effectiveness of VR in the postural rehabilitation of patients with PD. A scientific literature search was performed using the following databases: PubMed, PEDro, Cochrane, and Google Scholar, focusing on randomized controlled trials (RCTs) published in English. Our selection criteria included studies that compared VR-based rehabilitation to traditional methods regarding posture-related outcomes. We identified and analyzed nine RCTs that met our inclusion criteria. The results consistently demonstrated that VR-based rehabilitation leads to greater improvements in balance and gait compared to conventional therapy. Key findings include significant enhancements in balance confidence and postural control and a reduction in fall rates. The superior efficacy of VR-based rehabilitation can be attributed to its engaging and immersive nature, which enhances patient motivation and adherence to therapy. VR allows for precise, repeatable training scenarios tailored to individual patient needs, providing a safe environment to practice and improve motor skills. In conclusion, VR-based rehabilitation represents an innovative approach with substantial potential to improve the quality of life for PD patients. However, limitations such as small sample sizes and short intervention durations in existing studies highlight the need for larger multicenter trials with longer follow-up periods to confirm these findings.

Exceeding the Limits with Nutraceuticals: Looking Towards Parkinson's Disease and Frailty

One of the most pressing challenges facing society today is the rising prevalence of physical and cognitive frailty. This geriatric condition makes older adults more vulnerable to disability, illness, and a heightened risk of mortality. In this scenario, Parkinson's disease (PD) and geriatric frailty, which share several common characteristics, are becoming increasingly prevalent worldwide, underscoring the urgent need for innovative strategies. Nutraceuticals are naturally occurring bioactive compounds contained in foods, offering health benefits over and above essential nutrition. By examining the literature from the past decade, this review highlights how nutraceuticals can act as complementary therapies, addressing key processes, such as oxidative stress, inflammation, and neuroprotection. Notably, the antioxidant action of nutraceuticals appears particularly beneficial in regard to PD and geriatric frailty. For instance, antioxidant-rich nutraceuticals may mitigate the oxidative damage linked to levodopa therapy in PD, potentially reducing the side effects and enhancing treatment sustainability. Similarly, the antioxidant effects of nutraceuticals may amplify the benefits of physical activity, enhancing muscle function, cognitive health, and resilience, thereby reducing the risk of frailty. This review proposes a holistic approach integrating nutraceuticals with exercise, pharmacotherapy, and lifestyle adjustments. It promises to transform the management of ARD, prolong life, and improve the quality of life and well-being of older people.

The Combined Use of Levodopa/Benserazide and Pramipexole Proves Beneficial for Managing Parkinson's Disease

BACKGROUND

Parkinson's disease (PD), a prevalent neurological condition, is characterized by the progressive degeneration of dopamine-producing neurons, leading to motor dysfunction and non-motor symptoms. Therefore, this study aimed to evaluate the impact of combining levodopa/benserazide with pramipexole on PD patients, focusing on cognitive function, plasma monoamine neurotransmitter levels, and serum growth differentiation factor-15 (GDF-15) and angiopoietin-1 (Ang-1) levels.

METHODS

This retrospective study included 120 PD patients admitted to the hospital between January 2021 and January 2023. Based on the treatment approaches, the patients were categorized into the control group (n = 61) and the observation group (n = 59). The control group received oral levodopa/benserazide tablets, while the observation group was treated with levodopa/benserazide tablets combined with pramipexole. The two experimental groups were assessed and compared across several parameters, including PD symptoms [Unified Parkinson's Disease Rating Scale (UPDRS)], cognitive function [Montreal Cognitive Assessment (MoCA)], the levels of plasma monoamine neurotransmitters, and serum GDF-15 and Ang-1 levels.

RESULTS

The response rate to treatment was more significant in the observation group (96.55%) compared to the control group (87.93%, p = 0.162). Post-treatment, both groups demonstrated a decline in their UPDRS and overall scores, with the observation group indicating substantially lower scores than the control group (p < 0.05). Furthermore, both groups showed improvements in MoCA scores, with the observation group exhibiting higher scores than the control group (p < 0.05). Similarly, we observed significantly increased dopamine, 5-hydroxytryptamine, and norepinephrine levels in both groups, with the observation group showing a more pronounced increase (p < 0.05). Additionally, we observed a significant decrease in serum GDF-15 levels and an increase in Ang-1 levels across both groups after treatment. However, the observation group exhibited lower GDF-15 levels and higher Ang-1 levels than the control group (p < 0.05).

CONCLUSIONS

The combined use of levodopa/benserazide and pramipexole proves beneficial for managing PD. This therapeutic regimen can improve cognitive abilities and plasma monoamine neurotransmitter levels in PD patients, reduce brain tissue damage and decrease serum levels of GDF-15.

Exploring α-synuclein Interaction Partners and their Potential Clinical Implications for Parkinson's Disease

Alpha-synuclein aggregates are strongly associated with Parkinson's disease (PD), a degenerative neurological disorder characterized by a progressive loss in motor functions. Our study aimed to unravel the potential interaction partners of α-synuclein for exploring the synucleinpathy of PD related to α-synuclein aggregates. α-synuclein was expressed in E.coli and purified by affinity chromatography followed by isolation and identification of its interaction partners using pulldown assay coupled with LC-MS/MS. The impacts of the identified interaction partners on PD were evaluated based on GSE205450 dataset. Consequently, 157 proteins were identified by the criteria of unique peptide = 5. Four proteins including ACO2, ANT1, ATP5F1B and CKB were confirmed using immunostaining coupled with α-synuclein-pulldown assay. Transcriptomics assay showed that the dominant biological processes influenced by α-synuclein interaction partners with differential expression were energy metabolism. Together with GSE205450, Western blot assay showed that α-synuclein interaction partners involved in energy metabolism were down-regulated in PD patients and the MPTP-lesioned mice. ROC curves indicated their clinical implications as diagnostic indices of PD. Using ANT1 as an example, we found that protein aggregates formed by ANT1 and α-synuclein predominantly solely appeared in the cells and mice with PD-like variations. Thereby, low levels of the interaction partners of α-synuclein associated with energy metabolism were associated with PD pathogenesis via forming protein aggregates. This study provides an insight into developing innovative targets on PD based on synucleinpathy.

Non-coding RNAs as therapeutic targets in Parkinson's Disease: A focus on dopamine

Parkinson's Disease is a highly complicated neurological disorder, with a key manifestation of loss of dopaminergic neurons. Despite the plethora of medicines that alleviate the symptoms, there is an urgent need for new treatments acting on the fundamental pathology of PD. Non-coding RNAs are becoming increasingly important in gene regulation and various cellular processes and are found to play a role in PD pathophysiology. This review analyzes the cross-talk of distinct ncRNAs with dopamine signaling. We attempt to constrain the various ncRNA networks that can activate dopamine production. First, we describe the deregulation of miRNAs that target dopamine receptors and have been implicated in PD. Next, we turn to the functions of lncRNAs in dopaminergic neurons and the connections to susceptibility genes for PD. Finally, we will analyze the novel circRNAs, such as ciRS-7, which may modulate dopamine-linked processes and serve as possible PD biomarkers. In this review, we describe recent progress in dopamine neuron revival to treat PD and the therapeutic potential of ncRNA. This review critically evaluates the available data, and we predict the role of some ncRNAs, such as PTBP1, to become candidate treatment targets in the future. Thus, this review aims to summarize the molecular causes for the deficit in dopamine signaling in PD and point to novel ncRNAs-linked therapeutic directions in neuroscience.

Pharmacological activities and therapeutic potential of Hyperoside in the treatment of Alzheimer's and Parkinson's diseases: A systemic review

Alzheimer's disease (AD) and Parkinson's disease (PD) are neurodegenerative disorders that significantly impact well-being. Hyperoside (HYP), a flavonoid found in various plant species, particularly within the genus Hypericin, exhibits diverse pharmacological properties. However, the precise mechanisms underlying the anti-AD and anti-PD effects of HYP remain unclear. This systematic review consolidated existing preclinical research on HYP by conducting a comprehensive literature survey and analysis. The objective was to corroborate the therapeutic efficacy of HYP in AD and PD models and to synthesize its potential therapeutic mechanisms. Searches were conducted in the PubMed, CNKI, and Web of Science databases. Reliability assessment of the 17 included studies confirmed the credibility of the mechanisms of action of HYP against AD and PD. We systematically assessed the neuroprotective potential of HYP in in vivo and in vitro models of AD and PD. Our findings indicated that HYP can mitigate, intervene in, and treat AD and PD animal models and associated cells through various mechanisms, including anti-oxidative, anti-inflammatory, anti-apoptotic, anti-Aβ aggregation, and cholinesterase inhibitory activities. Therefore, HYP potentially exerts anti-AD and anti-PD effects through diverse mechanisms, making it a promising candidate for therapeutic intervention in both AD and PD.

Therapeutic potential of fucoidan in central nervous system disorders: A systematic review

Central nervous system (CNS) disorders have a complicated pathogenesis, and to date, no single mechanism can fully explain them. Most drugs used for CNS disorders primarily aim to manage symptoms and delay disease progression, and none have demonstrated any pathological reversal. Fucoidan is a safe, sulfated polysaccharide from seaweed that exhibits multiple pharmacological effects, and it is anticipated to be a novel treatment for CNS disorders. To assess the possible clinical uses of fucoidan, this review aims to provide an overview of its neuroprotective mechanism in both in vivo and in vitro CNS disease models, as well as its pharmacokinetics and safety. We included 39 articles on the pharmacology of fucoidan in CNS disorders. In vitro and in vivo experiments demonstrate that fucoidan has important roles in regulating lipid metabolism, enhancing the cholinergic system, maintaining the functional integrity of the blood-brain barrier and mitochondria, inhibiting inflammation, and attenuating oxidative stress and apoptosis, highlighting its potential for CNS disease treatment. Fucoidan has a protective effect against CNS disorders. With ongoing research on fucoidan, it is expected that a natural, highly effective, less toxic, and highly potent fucoidan-based drug or nutritional supplement targeting CNS diseases will be developed.

Non-Negative Matrix Tri-Factorization for Representation Learning in Multi-Omics Datasets with Applications to Drug Repurposing and Selection

The vast corpus of heterogeneous biomedical data stored in databases, ontologies, and terminologies presents a unique opportunity for drug design. Integrating and fusing these sources is essential to develop data representations that can be analyzed using artificial intelligence methods to generate novel drug candidates or hypotheses. Here, we propose Non-Negative Matrix Tri-Factorization as an invaluable tool for integrating and fusing data, as well as for representation learning. Additionally, we demonstrate how representations learned by Non-Negative Matrix Tri-Factorization can effectively be utilized by traditional artificial intelligence methods. While this approach is domain-agnostic and applicable to any field with vast amounts of structured and semi-structured data, we apply it specifically to computational pharmacology and drug repurposing. This field is poised to benefit significantly from artificial intelligence, particularly in personalized medicine. We conducted extensive experiments to evaluate the performance of the proposed method, yielding exciting results, particularly compared to traditional methods. Novel drug-target predictions have also been validated in the literature, further confirming their validity. Additionally, we tested our method to predict drug synergism, where constructing a classical matrix dataset is challenging. The method demonstrated great flexibility, suggesting its applicability to a wide range of tasks in drug design and discovery.

Human-mouse chimeric brain models constructed from iPSC-derived brain cells: Applications and challenges

The establishment of reliable human brain models is pivotal for elucidating specific disease mechanisms and facilitating the discovery of novel therapeutic strategies for human brain disorders. Human induced pluripotent stem cell (iPSC) exhibit remarkable self-renewal capabilities and can differentiate into specialized cell types. This makes them a valuable cell source for xenogeneic or allogeneic transplantation. Human-mouse chimeric brain models constructed from iPSC-derived brain cells have emerged as valuable tools for modeling human brain diseases and exploring potential therapeutic strategies for brain disorders. Moreover, the integration and functionality of grafted stem cells has been effectively assessed using these models. Therefore, this review provides a comprehensive overview of recent progress in differentiating human iPSC into various highly specialized types of brain cells. This review evaluates the characteristics and functions of the human-mouse chimeric brain model. We highlight its potential roles in brain function and its ability to reconstruct neural circuitry in vivo. Additionally, we elucidate factors that influence the integration and differentiation of human iPSC-derived brain cells in vivo. This review further sought to provide suitable research models for cell transplantation therapy. These research models provide new insights into neuropsychiatric disorders, infectious diseases, and brain injuries, thereby advancing related clinical and academic research.

The principles and promising future of sonogenetics for precision medicine

Sonogenetics is an emerging medical technology that uses acoustic waves to control cells through sonosensitive mediators (SSMs) that are genetically encoded, thus remotely and non-invasively modulating specific molecular events and/or biomolecular functions. Sonogenetics has opened new opportunities for targeted spatiotemporal manipulation in the field of gene and cell-based therapies due to its inherent advantages, such as its noninvasive nature, high level of safety, and deep tissue penetration. Sonogenetics holds impressive potential in a wide range of applications, from tumor immunotherapy and mitigation of Parkinsonian symptoms to the modulation of neural reward pathway, and restoration of vision. This review provides a detailed overview of the mechanisms and classifications of established sonogenetics systems and summarizes their applications in disease treatment and management. The review concludes by highlighting the challenges that hinder the further progress of sonogenetics, paving the way for future advances.

20-Week intramuscular toxicity study of rotigotine behenate extended-release microspheres for injection via intramuscular injection in cynomolgus monkeys

Continuous dopaminergic stimulation (CDS) has become an important strategy for the development of drugs to treat Parkinson's disease (PD). Rotigotine behenate extended-release microspheres (RBEM) for injection represents a new treatment regime for CDS and is being applied for clinical trial. Our study in cynomolgus monkeys was a 20-week repeat dose toxicity investigation with RBEM at dosages of 90, 180, 360, with a 12-week recovery period. The results observed some irritations in the application site and surrounding tissues in Placebo microspheres and each dose of RBEM, was accompanied with increased white blood count and fibrinogen. RBEM-treated monkeys were additionally noted with a pharmacological action-related decrease in prolactin. These findings showed certain reversibility after the 12-week recovery phase. No clear sex difference was noted in the plasma exposure to rotigotine. The exposure generally increased in a dose-proportional manner. In summary, major toxicological effects are associated with the dopamine agonist-related properties of rotigotine, and the removal of foreign bodies caused by p oly (lactide-co-glycolide) (PLGA)and sodium carboxymethyl cellulose (SCMC), and the no-observed-adverse-effect-level (NOAEL) was 360 mg/kg.

Neuroinflammation in Parkinson's disease: focus on the relationship between miRNAs and microglia

Parkinson's disease (PD) is a prevalent neurodegenerative disorder that affects the central nervous system (CNS). Neuroinflammation is a crucial factor in the pathological advancement of PD. PD is characterized by the presence of activated microglia and increased levels of proinflammatory factors, which play a crucial role in its pathology. During the immune response of PD, microglia regulation is significantly influenced by microRNA (miRNA). The excessive activation of microglia, persistent neuroinflammation, and abnormal polarization of macrophages in the brain can be attributed to the dysregulation of certain miRNAs. Additionally, there are miRNAs that possess the ability to inhibit neuroinflammation. miRNAs, which are small non-coding epigenetic regulators, have the ability to modulate microglial activity in both normal and abnormal conditions. They also have a significant impact on promoting communication between neurons and microglia.

A Comprehensive Approach to Parkinson's Disease: Addressing Its Molecular, Clinical, and Therapeutic Aspects

Parkinson's disease (PD) is a gradually worsening neurodegenerative disorder affecting the nervous system, marked by a slow progression and varied symptoms. It is the second most common neurodegenerative disease, affecting over six million people in the world. Its multifactorial etiology includes environmental, genomic, and epigenetic factors. Clinical symptoms consist of non-motor and motor symptoms, with motor symptoms being the classic presentation. Therapeutic approaches encompass pharmacological, non-pharmacological, and surgical interventions. Traditional pharmacological treatment consists of administering drugs (MAOIs, DA, and levodopa), while emerging evidence explores the potential of antidiabetic agents for neuroprotection and gene therapy for attenuating parkinsonian symptoms. Non-pharmacological treatments, such as exercise, a calcium-rich diet, and adequate vitamin D supplementation, aim to slow disease progression and prevent complications. For those patients who have medically induced side effects and/or refractory symptoms, surgery is a therapeutic option. Deep brain stimulation is the primary surgical option, associated with motor symptom improvement. Levodopa/carbidopa intestinal gel infusion through percutaneous endoscopic gastrojejunostomy and a portable infusion pump succeeded in reducing "off" time, where non-motor and motor symptoms occur, and increasing "on" time. This article aims to address the general aspects of PD and to provide a comparative comprehensive review of the conventional and the latest therapeutic advancements and emerging treatments for PD. Nevertheless, further studies are required to optimize treatment and provide suitable alternatives.

Gut-Brain Axis in Focus: Polyphenols, Microbiota, and Their Influence on α-Synuclein in Parkinson's Disease

With the recognition of the importance of the gut-brain axis in Parkinson's disease (PD) etiology, there is increased interest in developing therapeutic strategies that target α-synuclein, the hallmark abhorrent protein of PD pathogenesis, which may originate in the gut. Research has demonstrated that inhibiting the aggregation, oligomerization, and fibrillation of α-synuclein are key strategies for disease modification. Polyphenols, which are rich in fruits and vegetables, are drawing attention for their potential role in this context. In this paper, we reviewed how polyphenols influence the composition and functional capabilities of the gut microbiota and how the resulting microbial metabolites of polyphenols may potentially enhance the modulation of α-synuclein aggregation. Understanding the interaction between polyphenols and gut microbiota and identifying which specific microbes may enhance the efficacy of polyphenols is crucial for developing therapeutic strategies and precision nutrition based on the microbiome.

FOXA1 Suppresses Endoplasmic Reticulum Stress, Oxidative Stress, and Neuronal Apoptosis in Parkinson's Disease by Activating PON2 Transcription

Endoplasmic reticulum (ER) stress and oxidative stress (OS) are often related states in pathological conditions including Parkinson's disease (PD). This study investigates the role of anti-oxidant protein paraoxonase 2 (PON2) in ER stress and OS in PD, along with its regulatory molecule. PD was induced in C57BL/6 mice using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) treatment and in SH-SY5Y cells using 1-methyl-4-phenylpyridinium. PON2 was found to be poorly expressed in the substantia nigra pars compacta (SNc) of PD mice, and its overexpression improved motor coordination of mice. Through the evaluation of tyrosine hydroxylase, dopamine transporter, reactive oxygen species (ROS), and C/EBP homologous protein (CHOP) levels and neuronal loss in mice, as well as the examination of CHOP, glucose-regulated protein 94 (GRP94), GRP78, caspase-12, sarco/endoplasmic reticulum calcium ATPase 2, malondialdehyde, and superoxide dismutase levels in SH-SY5Y cells, we observed that PON2 overexpression mitigated ER stress, OS, and neuronal apoptosis both in vivo and in vitro. Forkhead box A1 (FOXA1) was identified as a transcription factor binding to the PON2 promoter to activate its transcription. Upregulation of FOXA1 similarly protected against neuronal loss by alleviating ER stress and OS, while the protective roles were abrogated by additional PON2 silencing. In conclusion, this study demonstrates that FOXA1-mediated transcription of PON2 alleviates ER stress and OS, ultimately reducing neuronal apoptosis in PD.

Assessment of noninvasive brain stimulation interventions in Parkinson's disease: a systematic review and network meta-analysis

A network meta-analysis of randomized controlled trials was conducted to compare and rank the effectiveness of various noninvasive brain stimulation (NIBS) for Parkinson's disease (PD). We searched PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Database, China Science and Technology Journal Database (VIP), and Chinese Biomedical Literature Service System (SinoMed) databases from the date of database inception to April 30th, 2024. Two researchers independently screened studies of NIBS treatment in patients with PD based on inclusion and exclusion criteria. Two researchers independently performed data extraction of the included studies using an Excel spreadsheet and assessed the quality of the literature according to the Cochrane Risk of Bias Assessment Tool (RoB2). Network meta-analysis was performed in StataMP 17.0. A total of 28 studies involving 1628 PD patients were included. The results showed that HF-rTMS over the SMA (SMD = - 2.01; 95% CI [- 2.87, - 1.15]), HF-rTMS over the M1 and DLPFC (SMD = - 1.80; 95% CI [- 2.90, - 0.70]), HF-rTMS over the M1 (SMD = - 1.10; 95% CI [- 1.55, - 0.65]), a-tDCS over the DLPFC (SMD = - 1.08; 95% CI [- 1.90, - 0.27]), HF-rTMS over the M1 and PFC (SMD = - 0.92; 95% CI [- 1.71, - 0.14]), LF-rTMS over the M1 (SMD = - 0.72; 95% CI [- 1.17, - 0.28]), and HF-rTMS over the DLPFC (SMD = - 0.70; 95% CI [- 1.21, - 0.19]) were significantly improved motor function compared with sham stimulation. The SUCRA three highest ranked were HF-rTMS over the SMA (95.1%), HF-rTMS over the M1 and DLPFC (89.6%), and HF-rTMS over the M1 (73.0%). In terms of enhanced cognitive function, HF-rTMS over the DLPFC (SMD = 0.80; 95% CI [0.03,1.56]) was significantly better than sham stimulation. The SUCRA three most highly ranked were a-tDCS over the M1 (69.8%), c-tDCS over the DLPFC (66.9%), and iTBS over the DLPFC (65.3%). HF-rTMS over the M1 (SMD = - 1.43; 95% CI [- 2.26, - 0.61]) and HF-rTMS over the DLPFC (SMD = - 0.79; 95% CI [- 1.45, - 0.12)]) significantly improved depression. The SUCRA three highest ranked were HF-rTMS over the M1 (94.1%), LF-rTMS over the M1 (71.8%), and HF-rTMS over the DLPFC (69.0%). HF-rTMS over the SMA may be the best option for improving motor symptoms in PD patients. a-tDCS and HF-rTMS over the M1 may be the NIBS with the most significant effects on cognition and depression, separately.Trial registration: International Prospective Register of Systematic Review, PROSPERO (CRD42023456088).

Neuroinflammation: A Critical Factor in Neurodegenerative Disorders

This review offers a comprehensive review of the signals and the paramount role neuroinflammation plays in neurodegenerative diseases such as Alzheimer's, Parkinson's, Huntington's, and amyotrophic lateral sclerosis. The study explores the sophisticated interactions between microglial, astrocytic, and dendritic cells and how neuroinflammation affects long-term neuronal damage and dysfunction. There are specific pathways related to the mentioned inflammatory processes, including Janus kinases/signal transducer and activator of transcriptions, nuclear factor-κB, and mitogen-activated protein kinases pathways. Neuroinflammation is argued to be a double-edged sword, being not only a protective agent that prevents further neuron damage but also the causative factor in more cell injury development. This concept of contrasting inflammation with neuroprotection advocates for the use of therapeutic techniques that seek to modulate neuroinflammatory responses as part of the neurodegeneration treatment. The recent research findings are integrated with the established knowledge to help present a comprehensive image of neuroinflammation's impact on neurodegenerative diseases and its implications for future therapy.

Understanding the (epi)genetic dysregulation in Parkinson's disease through an integrative brain competitive endogenous RNA network

Parkinson's disease (PD) is a rapidly growing neurodegenerative disorder characterized by dopaminergic neuron loss in the substantia nigra pars compacta (SN) and aggregation of α-synuclein. Its aetiology involves a multifaceted interplay among genetic, environmental, and epigenetic factors. We integrated brain gene expression data from PD patients to construct a comprehensive regulatory network encompassing messenger RNAs (mRNAs), microRNAs (miRNAs), circular RNAs (circRNAs) and, for the first time, RNA binding proteins (RBPs). Expression data from the SN of PD patients and controls were systematically selected from public databases to identify combined differentially expressed genes (DEGs). Brain co-expression analysis revealed modules comprising significant DEGs that function cooperatively. The relationships among co-expressed DEGs, miRNAs, circRNAs, and RBPs revealed an intricate competitive endogenous RNA (ceRNA) network responsible for post-transcriptional dysregulation in PD. Many genes in the ceRNA network, including the TOMM20 and HMGCR genes, overlap with the most relevant genes in our previous Alzheimer's disease-associated ceRNA network, suggesting common underlying mechanisms between both conditions. Moreover, in the ceRNA subnetwork, the RBP Aly/REF export factor (ALYREF), which acts as an RNA 5-methylcytosine(m5C)-binding protein, stood out. Our data sheds new light on the potential role of brain ceRNA networks in PD pathogenesis.

Nontargeted metabolomics reveals sequential changes in amino acid and ferroptosis-related metabolism in Parkinson's disease

Parkinson's disease (PD) is inseparable from metabolic disorders but lacks assessment of specific metabolite alteration. To explore the sequential metabolic changes in PD progression, we evenly divided 78 C57BL/6 mice (10 weeks) into six groups (one control group and five experimental groups) and collected the hippocampus tissue of mice after treating with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and probenecid (twice a week) at five periods (1, 2, 3, 4, and 5 weeks) for metabolome analysis. Our study identified 567 differentially abundant metabolites (DAMs) (total 4348 metabolites). Compared with controls, 145, 146, 171, 208, and 213 DAMs were obtained from the five experimental groups, respectively. Notably, 40 shared DAMs were present in five experimental groups, of which 22 shared DAMs formed a new metabolic network based on amino acid metabolism. Compared with group W3, 84 DAMs were identified in group W5, including 12 unique DAMs. DAMs in different stages of PD were significantly enriched in amino acid metabolism pathway, lipid metabolism pathway, and ferroptosis pathway. l-Glutamine, spermidine, and l-tryptophan were the key hubs in the whole metabolic process of PD. N-Formyl-l-methionine gradually increased in abundance with PD progression, whereas 5-methylcytosine gradually decreased. The study emphasized the sequential changes in DAMs in PD progression, stimulating subsequent studies.

Knocking down GRAMD1C expression reduces 6-OHDA-induced apoptosis in PC12 cells

Aim

To explore the differential genes in Parkinson's disease (PD) through a preliminary GEO database, and to investigate the possible mechanisms.

Materials and Methods

The PD differentially expressed genes (DEGs) were analyzed by the microarray method. Then, these DEGs were applied to KEGG and GO analyses to predict the related signaling pathways and molecular functions. Comparison of GRAMD1C expression levels in the putamen of normal and Parkinson's patients by bioinformatic analysis. PC12 cells were cultured to construct a 6-hydroxydopamine (6-OHDA)-induced Parkinson's cell model. RT-qPCR was performed to detect the efficiency of GRAMD1C siRNA. MTT assay was conducted to examine the proliferation of cells. Then, the apoptosis of each group of cells was measured by flow cytometry. Western blot was carried out to determine the expression of apoptosis-related proteins.

Results

Through bioinformatics, GRAMD1C was confirmed to be one of the most significantly upregulated genes in PD. Furthermore, GRAMD1C was notably enhanced in the PD patients and 6-OHDA-induced PC12 cells. Besides, 6-OHDA stimulation significantly reduced PC12 cell proliferation, and it reverted with the GRAMD1C siRNA. Moreover, the flow cytometry results showed that knockdown of GRAMD1C could effectively reduce the high apoptosis rate of PC12 cells induced by 6-OHDA treatment. Similarly, western blot results found that 6-OHDA stimulation markedly increased the expression levels of Bax and Caspase 3Caspase 3 and decreased the Bcl-2 expression in PC12 cells, and GRAMD1C knockdown reversed these changes.

Conclusion

GRAMD1C is upregulated in PD, and may affect the PD process through the apoptotic pathway.

Knockdown of fat mass and obesity alleviates the ferroptosis in Parkinson's disease through m6A-NRF2-dependent manner

Emerging evidence has suggested that N6 -methyladenosine (m6 A) regulates the pathology of Parkinson's disease (PD). Nevertheless, the function of demethylase fat mass and obesity (FTO) associated pathogenesis is still not fully elucidated. Here, this research findings revealed that m6 A-modification was decreased in PD models, meanwhile, the FTO level upregulated in the PD models. Functionally, in N-methyl-4-phenylpyridinium (MPP+) treated SH-SY5Y cells, the ferroptosis significantly upregulated and FTO silencing mitigated the ferroptosis phenotype. Moreover, in silico assays indicated that nuclear factor erythroid 2-related factor-2 (NRF2) acted as the target of FTO, and FTO demethylated the m6 A modification from NRF2 mRNA. Furthermore, FTO impaired the NRF2 mRNA stability via m6 A-dependent pathway. Thus, our findings illustrated an important role of FTO on PD through m6 A-NRF2-ferroptosis manner. Taken together, the study revealed the potential function of FTO on PD nervous system diseases.

Transplantation of human neural stem cell prevents symptomatic motor behavior disability in a rat model of Parkinson's disease

Parkinson's disease (PD) is a ubiquitous brain cell degeneration disease and presents a significant therapeutic challenge. By injecting 6-hydroxydopamine (6-OHDA) into the left medial forebrain bundle, rats were made to exhibit PD-like symptoms and treated by intranasal administration of a low-dose (2 × 105) or high-dose (1 × 106) human neural stem cells (hNSCs). Apomorphine-induced rotation test, stepping test, and open field test were implemented to evaluate the motor behavior and high-performance liquid chromatography was carried out to detect dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), serotonin, and 5-hydroxyindole-3-acetic acid in the striatum of rats. Animals injected with 6-OHDA showed significant motor function deficits and damaged dopaminergic system compared to the control group, which can be restored by hNSCs treatment. Treatment with hNSCs significantly increased the tyrosine hydroxylase-immunoreactive cell count in the substantia nigra of PD animals. Moreover, the levels of neurotransmitters exhibited a significant decline in the striatum tissue of animals injected with 6-OHDA when compared to that of the control group. However, transplantation of hNSCs significantly elevated the concentration of DA and DOPAC in the injured side of the striatum. Our study offered experimental evidence to support prospects of hNSCs for clinical application as a cell-based therapy for PD.

Investigating the TLR4/TAK1/IRF7 axis in NLRP3-Mediated Pyroptosis in Parkinson's Disease

In the realm of Parkinson's disease (PD) research, NLRP3 inflammasome-mediated pyroptosis has recently garnered significant attention as a potential novel form of dopaminergic neuronal death. Our previous research revealed the activation of innate immune-related genes, such as the TLR4 signaling pathway and interferon regulatory factor 7 (IRF7), although the specific mechanism remains unclear. Our current study shed light on whether the TLR4 signaling pathway and IRF7 can affect the pyroptosis of dopaminergic nerve cells and thus participate in the pathogenesis of PD. The PD model was constructed by MPP+ treatment of PC12 cells or stereotactic injection of the striatum of SD rats, and the expression of genes were detected by RT-qPCR and Western Blotting. Lentivirus, siRNA and (5Z)-7-Oxozeaenol were used to validate the regulation of this pathway on pyroptosis. The expression of TLR4, TAK1, IRF7 and pyroptosis molecular markers was upregulated after MPP+ treatment. IRF7 could affect dopaminergic neural cells pyroptosis by targeted regulation of NLRP3. Furthermore, inhibition of the TLR4/TAK1 signaling pathway led to a decrease in the expression of both IRF7 and NLRP3, while overexpression of IRF7 reversed the reduction in pyroptosis and increase in TH expression. TLR4/TAK1/IRF7 axis can promote PD by influencing pyroptosis through NLRP3.

Photobiomodulation for Neurodegenerative Diseases: A Scoping Review

Neurodegenerative diseases involve the progressive dysfunction and loss of neurons in the central nervous system and thus present a significant challenge due to the absence of effective therapies for halting or reversing their progression. Based on the characteristics of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD), which have prolonged incubation periods and protracted courses, exploring non-invasive physical therapy methods is essential for alleviating such diseases and ensuring that patients have an improved quality of life. Photobiomodulation (PBM) uses red and infrared light for therapeutic benefits and functions by stimulating, healing, regenerating, and protecting organizations at risk of injury, degradation, or death. Over the last two decades, PBM has gained widespread recognition as a non-invasive physical therapy method, showing efficacy in pain relief, anti-inflammatory responses, and tissue regeneration. Its application has expanded into the fields of neurology and psychiatry, where extensive research has been conducted. This paper presents a review and evaluation of studies investigating PBM in neurodegenerative diseases, with a specific emphasis on recent applications in AD and PD treatment for both animal and human subjects. Molecular mechanisms related to neuron damage and cognitive impairment are scrutinized, offering valuable insights into PBM's potential as a non-invasive therapeutic strategy.

The Potentiality of Natural Products and Herbal Medicine as Novel Medications for Parkinson's Disease: A Promising Therapeutic Approach

As the global population ages, the prevalence of Parkinson's disease (PD) is steadily on the rise. PD demonstrates chronic and progressive characteristics, and many cases can transition into dementia. This increases societal and economic burdens, emphasizing the need to find effective treatments. Among the widely recognized causes of PD is the abnormal accumulation of proteins, and autophagy dysfunction accelerates this accumulation. The resultant Lewy bodies are also commonly found in Alzheimer's disease patients, suggesting an increased potential for the onset of dementia. Additionally, the production of free radicals due to mitochondrial dysfunction contributes to neuronal damage and degeneration. The activation of astrocytes and the M1 phenotype of microglia promote damage to dopamine neurons. The drugs currently used for PD only delay the clinical progression and exacerbation of the disease without targeting its root cause, and come with various side effects. Thus, there is a demand for treatments with fewer side effects, with much potential offered by natural products. In this study, we reviewed a total of 14 articles related to herbal medicines and natural products and investigated their relevance to possible PD treatment. The results showed that the reviewed herbal medicines and natural products are effective against lysosomal disorder, mitochondrial dysfunction, and inflammation, key mechanisms underlying PD. Therefore, natural products and herbal medicines can reduce neurotoxicity and might improve both motor and non-motor symptoms associated with PD. Furthermore, these products, with their multi-target effects, enhance bioavailability, inhibit antibiotic resistance, and might additionally eliminate side effects, making them good alternative therapies for PD treatment.

Electroconductive Collagen-Carbon Nanodots Nanocomposite Elicits Neurite Outgrowth, Supports Neurogenic Differentiation and Accelerates Electrophysiological Maturation of Neural Progenitor Spheroids

Neuronal disorders are characterized by the loss of functional neurons and disrupted neuroanatomical connectivity, severely impacting the quality of life of patients. This study investigates a novel electroconductive nanocomposite consisting of glycine-derived carbon nanodots (GlyCNDs) incorporated into a collagen matrix and validates its beneficial physicochemical and electro-active cueing to relevant cells. To this end, this work employs mouse induced pluripotent stem cell (iPSC)-derived neural progenitor (NP) spheroids. The findings reveal that the nanocomposite markedly augmented neuronal differentiation in NP spheroids and stimulate neuritogenesis. In addition, this work demonstrates that the biomaterial-driven enhancements of the cellular response ultimately contribute to the development of highly integrated and functional neural networks. Lastly, acute dizocilpine (MK-801) treatment provides new evidence for a direct interaction between collagen-bound GlyCNDs and postsynaptic N-methyl-D-aspartate (NMDA) receptors, thereby suggesting a potential mechanism underlying the observed cellular events. In summary, the findings establish a foundation for the development of a new nanocomposite resulting from the integration of carbon nanomaterials within a clinically approved hydrogel, toward an effective biomaterial-based strategy for addressing neuronal disorders by restoring damaged/lost neurons and supporting the reestablishment of neuroanatomical connectivity.

Parkinson's Neuropathology Puzzle: A Systematic Review Uncovering the Pathological Culprits Behind the Neurological Disease

Being one of the most prevalent progressive neurodegenerative disorders (falling second only to Alzheimer's disease) with a clinical pattern affecting millions of lives all over the world, Parkinson's disease (PD) has never failed to attract a formidable interest from the vast majority of neurologists and researchers worldwide. This review article will analyze the pathophysiology, etiology, genetics, and pathological stages of Parkinson's disease with their corresponding clinical sequels. A review article was conducted using research databases including PubMed, PubMed Central, Springer, and Elsevier. The research articles reviewed using databases were written in English, German, Japanese, and Chinese and published within the preceding 50 years. Based on the article's findings, we concluded that Parkinson's disease is a progressive disorder with a variety of motor and non-motor symptoms that are influenced by a cascade of pathological neuronal abnormalities such as Lewy neurites and Lewy bodies that gradually build up with an eventual consequence of neurodegeneration of dopamine-secreting neurons. Multiple genetic mutations, pathophysiological events, and environmental factors act as the foundation to initiate that cascade.

Dephosphorylation of Six2Y129 protects tyrosine hydroxylase-positive cells in SNpc by regulating TEA domain 1 expression

Parkinson's disease (PD) is a neurodegenerative disease characterized by selective loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). We recently reported that Six2 could reverse the degeneration of DA neurons in a dephosphorylation state. Here we further identified that Eya1 was the phosphatase of Six2 that could dephosphorylate the tyrosine 129 (Y129) site by forming a complex with Six2 in damaged DA cells. Dephosphorylated Six2 then translocates from the cytoplasm to the nucleus. Using ChIP-qPCR and dual luciferase assay, we found that dephosphorylated Six2 down-regulates TEA domain1 (Tead1) expression, thus inhibiting 6-hydroxydopamine (6-OHDA)-induced apoptosis in DA cells. Furthermore, we showed Six2Y129F/Tead1 signaling could protect against the loss of SNpc tyrosine hydroxylase-positive (TH+) cells and improve motor function in PD model rats. Our results demonstrate a dephosphorylation-dependent mechanism of Six2 that restores the degeneration of DA neurons, which could represent a potential therapeutic target for PD.

NEAT1 enhances MPP+ -induced pyroptosis in a cell model of Parkinson's disease via targeting miR-5047/YAF2 signaling

PURPOSE

Parkinson's disease (PD) is the second most frequent neurodegenerative disease. The aim of our study is to explore the role and the regulatory mechanism of long noncoding RNA (lncRNA) NEAT1 in MPP+ -induced pyroptosis in a cell model of PD.

MATERIALS AND METHODS

MPP+ -treated SH-SY5Y cells were used as an in vitro model of dopaminergic neurons for PD. Expression levels of miR-5047 and YAF2 mRNA were determined through qRT-PCR. TUNEL staining was carried out to analyze neuronal apoptosis. Luciferase activity assay was accomplished to analyze the combination of miR-5047 with NEAT1 or YAF2 3'-UTR region. Besides, concentrations of IL-1β and IL-18 in supernatant samples were analyzed by using ELISA assay. Expression level of proteins were examined through Western blot.

RESULTS

NEAT1 and YAF2 expression were increased, while miR-5047 expression was declined in the SH-SY5Y cells treated with MPP+ . NEAT1 was a positively regulator to SH-SY5Y cells pyroptosis induced by MPP+ . In addition, YAF2 was a downstream target of miR-5047. NEAT1 promoted YAF2 expression via inhibiting miR-5047. Importantly, the promotion of NEAT1 to SH-SY5Y cells pyroptosis induced by MPP+ was rescued by miR-5047 mimic transfection or YAF2 downregulation.

CONCLUSION

In conclusion, NEAT1 was increased in MPP+ -induced SH-SY5Y cells, and it promoted MPP+ -induced pyroptosis through facilitating YAF2 expression by sponging miR-5047.

Pathophysiology and Neuroimmune Interactions Underlying Parkinson's Disease and Traumatic Brain Injury

Parkinson's disease (PD) is a progressive neurodegenerative disorder clinically defined by motor instability, bradykinesia, and resting tremors. The clinical symptomatology is seen alongside pathologic changes, most notably the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the accumulation of α-synuclein and neuromelanin aggregates throughout numerous neural circuits. Traumatic brain injury (TBI) has been implicated as a risk factor for developing various neurodegenerative diseases, with the most compelling argument for the development of PD. Dopaminergic abnormalities, the accumulation of α-synuclein, and disruptions in neural homeostatic mechanisms, including but not limited to the release of pro-inflammatory mediators and the production of reactive oxygen species (ROS), are all present following TBI and are closely related to the pathologic changes seen in PD. Neuronal iron accumulation is discernable in degenerative and injured brain states, as is aquaporin-4 (APQ4). APQ4 is an essential mediator of synaptic plasticity in PD and regulates edematous states in the brain after TBI. Whether the cellular and parenchymal changes seen post-TBI directly cause neurodegenerative diseases such as PD is a point of considerable interest and debate; this review explores the vast array of neuroimmunological interactions and subsequent analogous changes that occur in TBI and PD. There is significant interest in exploring the validity of the relationship between TBI and PD, which is a focus of this review.

Paraoxonases at the Heart of Neurological Disorders

Paraoxonase enzymes serve as an important physiological redox system that participates in the protection against cellular injury caused by oxidative stress. The PON enzymes family consists of three members (PON-1, PON-2, and PON-3) that share a similar structure and location as a cluster on human chromosome 7. These enzymes exhibit anti-inflammatory and antioxidant properties with well-described roles in preventing cardiovascular disease. Perturbations in PON enzyme levels and their activity have also been linked with the development and progression of many neurological disorders and neurodegenerative diseases. The current review summarizes the available evidence on the role of PONs in these diseases and their ability to modify risk factors for neurological disorders. We present the current findings on the role of PONs in Alzheimer's disease, Parkinson's disease, and other neurodegenerative and neurological diseases.

A New Strategy for Nucleic Acid Delivery and Protein Expression Using Biocompatible Nanohydrogels of Predefined Sizes

We have developed new formulations of nanohydrogels (NHGs) complexed with DNA devoid of cell toxicity, which, together with their tuned sizes, makes them of great interest for delivering DNA/RNA for foreign protein expression. Transfection results demonstrate that, unlike classical lipo/polyplexes, the new NHGs can be incubated indefinitely with cells without apparent cellular toxicity, resulting in the high expression of foreign proteins for long periods of time. Although protein expression starts with a delay as compared to classical systems, it is sustained for a long period of time, even after passing cells without observation of toxicity. A fluorescently labelled NHG used for gene delivery was detected inside cells very early after incubation, but the protein expression was delayed by many days, demonstrating that there is a time-dependent release of genes from the NHGs. We suggest that this delay is due to the slow but continuous release of DNA from the particles concomitantly with slow but continuous protein expression. Additionally, results obtained after the in vivo administration of m-Cherry/NHG complexes indicated a delayed but prolonged expression of the marker gene in the tissue of administration. Overall, we have demonstrated gene delivery and foreign protein expression using GFP and m-Cherry marker genes complexed with biocompatible nanohydrogels.

Current Treatments and New, Tentative Therapies for Parkinson’s Disease

Parkinson’s disease (PD) is a neurodegenerative pathology, the origin of which is associated with the death of neuronal cells involved in the production of dopamine. The prevalence of PD has increased exponentially. The aim of this review was to describe the novel treatments for PD that are currently under investigation and study and the possible therapeutic targets. The pathophysiology of this disease is based on the formation of alpha-synuclein folds that generate Lewy bodies, which are cytotoxic and reduce dopamine levels. Most pharmacological treatments for PD target alpha-synuclein to reduce the symptoms. These include treatments aimed at reducing the accumulation of alpha-synuclein (epigallocatechin), reducing its clearance via immunotherapy, inhibiting LRRK2, and upregulating cerebrosidase (ambroxol). Parkinson’s disease continues to be a pathology of unknown origin that generates a significant social cost for the patients who suffer from it. Although there is still no definitive cure for this disease at present, there are numerous treatments available aimed at reducing the symptomatology of PD in addition to other therapeutic alternatives that are still under investigation. However, the therapeutic approach to this pathology should include a combination of pharmacological and non-pharmacological strategies to maximise outcomes and improve symptomatological control in these patients. It is therefore necessary to delve deeper into the pathophysiology of the disease in order to improve these treatments and therefore the quality of life of the patients.

Identification of immune signatures in Parkinson's disease based on co-expression networks

Parkinson's disease (PD) is a common neurodegenerative disease in middle-aged and elderly people, and there is less research on the relationship between immunity and PD. In this study, the protein-protein interaction networks (PPI) data, 2747 human immune-related genes (HIRGs), 2078 PD-related genes (PDRGs), and PD-related datasets (GSE49036 and GSE20292) were downloaded from the Human Protein Reference Database (HPRD), Amigo 2, DisGeNET, and Gene Expression Omnibus (GEO) databases, respectively. An immune- or PD-directed neighbor co-expressed network construction (IOPDNC) was drawn based on the GSE49036 dataset and HPRD database. Furthermore, a PD-directed neighbor co-expressed network was constructed. Modular clustering analysis was performed on the genes of the gene interaction network obtained in the first step to obtain the central core genes using the GraphWeb online website. The modules with the top 5 functional scores and the number of core genes greater than six were selected as PD-related gene modules. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of different module genes were performed. The single sample Gene Set Enrichment Analysis (ssGSEA) algorithm was used to calculate the immune cell infiltration of the PD and the normal samples. The quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) was performed to investigate the expression of module genes. An IOPDNC and PD-directed neighbor co-expressed network (PDNC network) were constructed. Furthermore, a total of 5 immune-PD modules were identified which could distinguish between PD and normal samples, and these module genes were strongly related to PD in protein interaction level or gene expression level. In addition, functional analysis indicated that module genes were involved in various neurodegenerative diseases, such as Alzheimer disease, Huntington disease, Parkinson disease, and Long-term depression. In addition, the genes of the 6 modules were significantly associated with these 4 differential immune cells (aDC cells, eosinophils, neutrophils, and Th2 cells). Finally, the result of qRT-PCR manifested that the expression of 6 module genes was significantly higher in normal samples than in PD samples. In our study, the immune-related genes were found to be strongly related to PD and might play key roles in PD.

Celastrol attenuates 6-hydroxydopamine-induced neurotoxicity by regulating the miR-146a/PI3K/Akt/mTOR signaling pathways in differentiated rat pheochromocytoma cells

BACKGROUND

Parkinson's disease (PD) is a neurological disorder. Recently, celastrol (Cel) has been reported to have neuroprotective properties. We investigated the protective effects of Cel on PD in a cell model with 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in PC12 cells and further addressed the underlying protective mechanisms of Cel.

METHODS

PC12 cells were treated with 6-OHDA, and Cel was added to the medium at various concentrations. The CCK-8 assay, Hoechst/PI staining, and flow cytometry analysis were performed to detect cellular viability and apoptosis. Mitochondrial membrane potential (MMP) was examined by JC-1 staining. ROS level was quantified by ROS staining. The effects of Cel on the expression of miR-146a and PI3K/Akt/mTOR pathway were then clarified using real-time PCR and Western blotting. Moreover, a miR-146a mimic was synthesized and transfected into PC12 cells to further determine the mechanisms of Cel's neuronal protection against 6-OHDA-induced neurotoxicity.

RESULTS

Cel greatly improved cell viability and lessened apoptosis. Flow cytometry showed that Cel especially inhibited early apoptosis. Cel also obviously restored the MMP and decreased ROS level destroyed by 6-OHDA. Moreover, 6-OHDA increased the expression of miR-146a and decreased pAkt/mTOR protein levels, whereas Cel reversed these changes. In particular, miR-146a targeted and inhibited the expression of PI3K, an upstream molecule of Akt/mTOR. Transfection of 6-OHDA-treated neurons with miR-146a mimic notably attenuated Cel's protective effects.

LIMITATIONS

There were no animal experiments in our study.

CONCLUSIONS

Cel exerts neuroprotective activity against 6-OHDA-caused neurotoxicity by regulating miR-146a/PI3K/Akt/mTOR pathway, which provides a potential application of Cel for treating neurodegenerative diseases.

From Rate-Limiting Enzyme to Therapeutic Target: The Promise of NAMPT in Neurodegenerative Diseases

Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme in the nicotinamide adenine dinucleotide (NAD) salvage pathway in mammals. It is of great significance in the metabolic homeostasis and cell survival via synthesizing nicotinamide mononucleotide (NMN) through enzymatic activities, serving as a key protein involved in the host's defense mechanism. The NAMPT metabolic pathway connects NAD-dependent sirtuin (SIRT) signaling, constituting the NAMPT-NAD-SIRT cascade, which is validated as a strong intrinsic defense system. Neurodegenerative diseases belong to the central nervous system (CNS) disease that seriously endangers human health. The World Health Organization (WHO) proposed that neurodegenerative diseases will become the second leading cause of human death in the next two decades. However, effective drugs for neurodegenerative diseases are scant. NAMPT is specifically highly expressed in the hippocampus, which mediates cell self-renewal and proliferation and oligodendrocyte synthesis by inducing the biosynthesis of NAD in neural stem cells/progenitor cells. Owing to the active biological function of NAMPT in neurogenesis, targeting NAMPT may be a powerful therapeutic strategy for neurodegenerative diseases. This study aims to review the structure and biological functions, the correlation with neurodegenerative diseases, and treatment advance of NAMPT, aiming to provide a novel idea for targeted therapy of neurodegenerative diseases.

Acupuncture for Parkinson's disease: From theory to practice

Advances in molecular biology and biochemistry have improved the treatment of Parkinson's disease (PD). There has been extensive evidence on the benefit of standard treatment (e.g., deep brain stimulation, levodopa, and dopamine agonists) and acupuncture for PD. This article aims to distill the similarities and differences in the treatment concepts between Chinese and Western medicine from the perspective of reinforcing the deficiency and purging the excess, summarize the latest evidence on the benefits of acupuncture for PD from theory to practice, and propose prospective treatment options for PD.

Non-invasive electrical stimulation of peripheral nerves for the management of tremor

Pathological tremor in patients with essential tremor and Parkinsons disease is typically treated using medication or neurosurgical interventions. There is a widely recognized need for new treatments that avoid the side effects of current medications and do not carry the risks of surgical interventions. Building on decades of research and engineering development, non-invasive electrical stimulation of peripheral nerves has emerged as a safe and effective strategy for reducing pathologic tremor in essential tremor. This review surveys the peripheral electrical stimulation (PES) literature and summarizes effectiveness, safety, clinical translatability, and hypothesized tremor-reduction mechanisms of various PES approaches. The review also proposes guidelines for assessing tremor in the context of evaluating new therapies that combine the strengths of clinician assessments, patient evaluations, and novel motion sensing technology. The review concludes with a summary of future directions for PES, including expanding clinical access for patients with Parkinson's disease and leveraging large, at-home datasets to learn more about tremor physiology and treatment effect that will better characterize the state of tremor management and accelerate discovery of new therapies. Growing evidence suggests that non-invasive electrical stimulation of afferent neural pathways provides a viable new option for management of pathological tremor, with one specific PES therapy cleared for prescription and home use, suggesting that PES be considered along with medication and neurosurgical interventions for treatment of tremor. This article is part of the Special Issue "Tremor" edited by Daniel D. Truong, Mark Hallett, and Aasef Shaikh.