Global Trends in the Incidence, Prevalence, and Years Lived With Disability of Parkinson's Disease in 204 Countries/Territories From 1990 to 2019

Melissa officinalis extract nanoemulsion, Caffeic acid and Quercetin as a novel inducer for investigating neural differentiation of human Wharton's jelly mesenchymal stem cells

BACKGROUND

Cell therapy utilizing mesenchymal stem cells, which have the ability to differentiate into different lineages, has garnered significant attention in recent years. Melissa officinalis is rich in biologically active compounds and exhibits antioxidant activity, antimicrobial properties, and sedative effects. Nanoemulsions can facilitate the effective transfer of substances and also protect drugs and biological materials from environmental factors. The aim of the present study is to investigate the role of Melissa officinalis extract nanoemulsion and the active ingredients of caffeic acid and quercetin as inducers in increasing the efficiency of differentiation of mesenchymal stem cells into neural cells in a laboratory environment.

MATERIALS AND METHODS

Human WJMSCs were cultured in the basic culture medium consisting of: Hight glucose DMEM, 10 % FBS and 1 % penicillin/streptomycin. The alcoholic extract of Melissa officinalis was extracted and its nanoemulsion was prepared along with two other effective substances. Next, zeta potential and size of nanoparticles were measured by Dynamic light scattering (DLS) technique. The optimal dose of all three material was calculated by MTT (3-4,5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide) assay and Acridine orange-ethidium bromide (AO/EB) staining. In the following, neural differentiation was investigated using Real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) and immunocytochemistry (ICC) techniques on days 7 and 14.

RESULTS

The results obtained from MTT and AO/EB assays showed that the optimal dose of nanoemulsion M. officinalis, caffeic acid and quercetin is 150 μg/ml, 75 μg/ml and 25 μg/ml, respectively. The ideal particle size for nanoemulsion is below 100 nm. The zeta potential of the M. officinalis extract nanoemulsion was reported to be -9.45 and the average particle size was 17.76 nm. The results of this study indicated that the expression of neural marker genes (MAP-2, β-tubulin III and NSE) and proteins (MAP-2, β-tubulin III and Gamma-enolase) increased in differentiated cells treated with the synthesized nanoemulsion compared to the control group on days 7 and 14 (P ≤ 0.05).

CONCLUSION

In general, our results showed that M. officinalis extract nanoemulsion, caffeic acid and quercetin caused induction of neural differentiation mechanism in human WJ-MSCs.

The interrelationship between intestinal immune cells and enteric α-synuclein in the progression of Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disorder primarily characterized by motor impairment, resulting from the accumulation of α-synuclein and neuronal cell death in the substantia nigra of the midbrain. Emerging evidence suggests that α-synuclein aggregation may originate in the enteric nervous system (ENS) and subsequently propagate to the brain via the vagus nerve. Clinical observations, such as prodromal gastrointestinal dysfunction in PD patients and the increased incidence of PD among individuals with inflammatory bowel disease, support the hypothesis that abnormal intestinal inflammation may contribute to the onset of motor dysfunction and neuropathology in PD. This review examines recent findings on the interplay between intestinal immune cells and α-synuclein aggregation within the framework of gut-originated PD pathogenesis. It begins by discussing evidence linking dysbiosis and intestinal inflammation to α-synuclein aggregation in the ENS. Additionally, it explores the potential role of intestinal immune cells in influencing enteric neurons and α-synuclein aggregation, furthering the understanding of PD development.

Lasting Impact: Exploring the Brain Mechanisms that Link Traumatic Brain Injury to Parkinson's Disease

Development of Parkinson's Disease (PD) is linked with a history of traumatic brain injury (TBI), although the mechanisms driving this remain unclear. Of note, many key parallels have been identified between the pathologies of PD and TBI; in particular, PD is characterised by loss of dopaminergic neurons from the substantia nigra (SN), accompanied by broader changes to dopaminergic signalling, disruption of the Locus Coeruleus (LC) and noradrenergic system, and accumulation of aggregated α-synuclein in Lewy Bodies, which spreads in a stereotypical pattern throughout the brain. Widespread disruptions to the dopaminergic and noradrenergic systems, including progressive neuronal loss from the SN and LC, have been observed acutely following injury, some of which have also been identified chronically in TBI patients and preclinical models. Furthermore, changes to α-synuclein expression are also seen both acutely and chronically following injury throughout the brain, although detailed characterisation of these changes and spread of pathology is limited. In this review, we detail the current literature regarding dopaminergic and noradrenergic disruption and α-synuclein pathology following injury, with particular focus on how these changes may predispose individuals to prolonged pathology and progressive neurodegeneration, particularly the development of PD. While it is increasingly clear that TBI is a key risk factor for the development of PD, significant gaps remain in current understanding of neurodegenerative pathology following TBI, particularly chronic manifestations of injury.

Neuroprotective effects and mechanisms of the YiQiWenYangSanHan formula on Parkinson's disease mice

Background

Parkinson's disease (PD) is a complex neurodegenerative disease, which is often treated with obvious side effects such as dopamine replacement therapy. Our team has validated the unique advantages of the traditional Chinese medicine formula, YiQiWenYangSanHan formula (YQWYSHF), through in vitro experiments, confirming its therapeutic potential for PD. Nevertheless, further research and validation are required to fully understand its protective effects and underlying mechanisms against PD.

Aim of this review

This study employed an in vivo model to investigate the effects of YQWYSHF on motor impairments, neuroinflammation, and mitochondrial dysfunction in C57BL/6 J mice caused by MPTP.

Materials and methods

Sixty C57BL/6 J mice were randomly divided into 5 groups, all groups except the control group were intraperitoneally administered MPTP for 7 days (30 mg/kg). After 4 weeks of drug intragastric treatment, we assessed the dyskinesia of mice treated with different doses of YQWYSHF by behavioral examination. Additionally, immunofluorescence was used to examine the expression of ionized calcium binding adaptor protein 1 (IBA1) and glial fibrillary acidic protein-positive (GFAP) cells. Western blotting was used to assess the expression level of tyrosine hydroxylase (TH), pyrin domain-containing 3 protein (NLRP3), apoptosis-associated speck-like proteins (ASC), cysteine-containing aspartate protease-1 (Caspase-1), interleukin-1β (IL-1β), α-synuclein (α-syn), poly (ADP-ribose) polymerase 1 (PARP1), and poly ADP ribose (PAR). Furthermore, transmission electron microscopy revealed mitochondrial impairment in the neuronal cells of the substantia nigra (SN).

Results

YQWYSHF treatment alleviated dyskinesia in a mouse model of PD. Moreover, it increased the TH expression, and could reverse the increase of IBA1, GFAP, NLRP3, ASC, caspase-1,IL-1β, α-syn, PARP1 and PAR proteins induced by MPTP.

Conclusions

YQWYSHF protects dopaminergic neurons in PD by attenuating neuroinflammation and mitochondrial dysfunction. This study provides new evidence for the clinical application of traditional Chinese medicine in the treatment of PD.

Combining Single-Cell RNA Sequencing and Mendelian Randomization to Explore Novel Drug Targets for Parkinson's Disease

Neuroinflammation is a key pathological factor of PD, and T cells play a central role in neuroinflammatory progression. However, the causal effect of T cell-related genes on the risk of PD is still unclear. We explored single-cell RNA sequencing (scRNA-Seq) datasets of the peripheral blood T cells of PD patients and healthy controls, and screened the differentially expressed genes (DEGs) in the cytotoxic CD4 + T cells relative to the other T cell subsets. Pseudo-time series analysis, cell-cell communication analysis, and metabolic pathway analysis was performed for the cytotoxic CD4 + T cells. The DEGs were also functionally annotated through GO and KEGG pathway enrichment analyses. The MR approach was used to establish causal effects of the DEGs (exposure) on PD risk (outcome), and explore new drug targets for PD. The findings of MR analysis were further validated by Steiger filtering, bidirectional MR, Bayesian colocalization analysis, and phenotype scanning, and the GWAS data from an independent PD case-control cohort was used for external validation of the results. Finally, differences in gene expression between PD patients and healthy controls were further validated in scRNA-Seq and bulk transcriptome sequencing data. We found that increased expression of IL-32, GNLY, MT2A, and ARPC2 was significantly associated with a higher risk of PD. In contrast, the increase in ARRB2 was closely related to a lower risk of PD. IL32, GNLY, MT2A, ARRB2, and ARPC2 are the causal genes and potential drug targets of PD. Cytotoxic CD4 + T cells are likely the key effectors of PD-related neuroinflammation. These findings provide new insights into the pathogenesis and treatment options for PD, and further research and clinical trials based on the five potential drug targets and neuroinflammation are necessary.

ADHD and Parkinson's disease: unraveling the link and implications for early intervention

BACKGROUND

Attention deficit/hyperactivity disorder (ADHD) and Parkinson's disease (PD) are neurodevelopmental and neurodegenerative conditions respectively, involving alterations in dopamine signaling pathways. Emerging evidence suggests ADHD may be a potential risk factor for earlier PD onset. However, rigorous investigation of this association is still lacking.

AIM

To examine the association between ADHD history and subsequent development of PD using a large retrospective cohort study.

METHODS

Patients aged ≥50 years were identified from clinician databases between 2010 and 2022 (N = 13,098) and categorized based on ADHD diagnosis. This retrospective cohort study employed Cox proportional hazards models to estimate hazard ratios (HR) for PD according to ADHD history, adjusting for demographic and clinical covariates. Kaplan-Meier survival analysis compared PD-free survival between ADHD and non-ADHD groups, while subgroup analyses explored the effects of ADHD medication use.

RESULTS

Individuals with a prior ADHD diagnosis had aa 33 % higher risk of PD (HR = 1.33, 95 % CI 1.12-1.58). Individuals with ADHD exhibited an earlier average age of PD onset. Kaplan-Meier curves demonstrated significantly poorer long-term PD-free survival among individuals with ADHD compared to those without. Subgroup analyses indicated that ADHD medication use did not significantly modify PD risk, as survival trends remained consistent across medicated and non-medicated groups.

CONCLUSION

This study provides compelling evidence that ADHD influences PD risk and age of onset. Having ADHD history appears to independently impact long-term PD outcomes. The results highlight a need for tailored monitoring approaches for individuals with ADHD who may face an accelerated PD trajectory. Further research should investigate mechanisms and preventive strategies for high-risk neurodevelopmental populations.

Benchmark CCSD(T) and Density Functional Theory Calculations of Biologically Relevant Catecholic Systems

Approximate complete basis set CCSD(T), MP2, and HF calculations are performed for thirty-two catechol-containing complexes. These complexes, which include metal-coordination, hydrogen-bonding, π-stacking, and other, weaker interactions, are representative of the types of noncovalent interactions that catechols undergo when binding to proteins in the body, such as in the biosynthesis of dopamine. The catechols studied include the neutral catechol and dinitrocatechol molecules, as well as the charged dopamine and DOPAC molecules. Calculations with twenty-one density functional theory methods with triple and quadruple-ζ basis sets are evaluated against the CCSD(T) benchmarks to ascertain their accuracy. It is found that MN15, M06-2X-D3, ωB97XD, ωB97M-V, and CAM-B3LYP-D3 provide good accuracy when compared with CCSD(T)/CBS calculations for these systems and may be used for the study of relevant biological systems. The local DPLNO CCSD(T) method is also evaluated against the CCSD(T)/CBS energies for a subset of the complexes and found to agree within 1-3%, with a maximum difference of 0.26 kcal/mol.

Association between Perceived Dysphagia Symptoms and Swallowing Physiology in Parkinson's Disease

BACKGROUND

Swallowing disorders are prevalent in Parkinson's disease (PD). Swallowing assessment often relies on patient-reported outcome measures (PROMs). Although PROMs and physiologic swallowing measures correlate with disease severity, the relationship between PROMs and physiologic swallowing impairments is unclear.

OBJECTIVES

Our aim was to (1) delineate the relationship between perceived swallowing symptoms and physiologic swallowing impairments; and (2) determine the relationship between swallowing-related quality of life (QoL) and physiologic impairments.

METHODS

A total of 31 individuals with PD (mean age = 64.8, standard deviation = 9.4) and dysphagia were recruited. PROMs included the Sydney Swallow Questionnaire (SSQ) and Swallowing Quality of Life Survey (SWAL-QOL) to measure perceived swallowing-related symptoms and QoL, respectively. Participants underwent a Modified Barium Swallow Study (MBSS) to obtain physiologic swallowing measures, including the Modified Barium Swallow Impairment Profile (MBSImP) and Penetration-Aspiration Scale (PAS). Multiple linear regression analyses assessed the associations between PROMs and physiologic measures, controlling for disease duration.

RESULTS

Perceived swallowing difficulties indicated mild to moderate symptoms (SSQ: 20-871.5), and perceived swallowing-related QoL showed moderate to no impact (SWAL-QOL: 52.5%-100%). Swallowing components oral residue (97%) and delayed pharyngeal swallow (97%) were the most frequently impaired on the MBSImP. Furthermore, 45.2% of participants showed airway invasion (PAS ≥3) in at least one swallow trial. Regression analysis showed significant associations between MBSImP pharyngeal total score with SSQ (P < 0.001, R2 = 0.49) and SWAL-QOL (P = 0.014, R2 = 0.36).

CONCLUSIONS

These findings suggest that PROMs may not fully capture all aspects of physiological swallowing impairments. Relying solely on PROMs may overlook critical swallowing deficits not perceived by the patient, highlighting the need for objective swallowing assessments in PD.

Machine learning in neuroimaging and computational pathophysiology of Parkinson's disease: A comprehensive review and meta-analysis

In recent years, machine learning and deep learning have shown potential for improving Parkinson's disease (PD) diagnosis, one of the most common neurodegenerative diseases. This comprehensive analysis examines machine learning and deep learning-based Parkinson's disease diagnosis using MRI, speech, and handwriting datasets. To thoroughly analyze PD, this study collected data from scientific literature, experimental investigations, publicly accessible datasets, and global health reports. This study examines the worldwide historical setting of Parkinson's disease, focusing on its increasing prevalence and inequities in treatment access across various regions. A comprehensive summary consolidates essential findings from clinical investigations and pertinent datasets related to Parkinson's disease management. The worldwide context, prospective treatments, therapies, and drugs for Parkinson's disease have been thoroughly examined. This analysis identifies significant research deficiencies and suggests future methods, emphasizing the necessity for more extensive and diverse datasets and improved model accessibility. The current study proposes the Meta-Park model for diagnosing Parkinson's disease, achieving training, testing, and validation accuracy of 97.67 %, 95 %, and 94.04 %. This method provides a dependable and scalable way to improve clinical decision-making in managing Parkinson's disease. This research seeks to provide innovative, data-driven decisions for early diagnosis and effective treatment by merging the proposed method with a thorough examination of existing interventions, providing renewed hope to patients and the medical community.

Amphetamine use and Parkinson's disease: integration of artificial intelligence prediction, clinical corroboration, and mechanism of action analyses

Parkinson's disease (PD) is an increasingly prevalent neurologic condition for which symptomatic, but not preventative, treatment is available. Drug repurposing is an innovate drug discovery method that uncovers existing therapeutics to treat or prevent conditions for which they are not currently indicated, a method that could be applied to incurable diseases such as PD. A knowledge graph artificial intelligence prediction system was used to select potential drugs that could be used to treat or prevent PD, and amphetamine was identified as the strongest candidate. Retrospective cohort analysis on a large, electronic health record database of deidentified patients with attention deficit hyperactive disorder (the main diagnosis for which amphetamine is prescribed) revealed a significantly reduced hazard of developing PD in patients prescribed amphetamine versus patients not prescribed amphetamine at 2, 4, and 6 years: Hazard Ratio (95% Confidence Interval) = 0.59 (0.36, 0.98), 0.63 (0.42, 0.93), and 0.55 (0.38, 0.79). Pathway enrichment analysis confirmed that amphetamine targets many of the biochemical processes implicated in PD, such as dopaminergic synapses and neurodegeneration. Together, these observational findings suggest that therapeutic and legal amphetamine use may reduce the risk of developing PD, in contrast to previous work that found the inverse relationship in patients using amphetamine recreationally.

The Hallmarks of Ageing in Microglia

As ageing is linked to the development of neurodegenerative diseases (NDs), such as Alzheimer's Disease and Parkinson's Disease, it is important to disentangle the independent effect of age-related changes from those due to disease processes. To do so, changes to central nervous system (CNS) cells as a function of advanced age need better characterisation. Microglia are of particular interest due to their proposed links with the development and progression of NDs through control of the CNS immune response. Therefore, understanding the extent to which microglial dysfunction is related to phyisological ageing, rather than a disease process, is critical. As microglia age, they are believed to take on a pro-inflammatory phenotype with a distinct dystrophic morphology. Nevertheless, while established hallmarks of ageing have been investigated across a range of other cell types, such as macrophages, a detailed consideration of functional changes that occur in aged microglia remains elusive. Here, we describe the dynamic phenotypes of microglia and evaluate the current state of understanding of microglial ageing, focusing on the recently updated twelve hallmarks of ageing. Understanding how these hallmarks present in microglia represents a step towards better characterisation of microglial ageing, which is essential in the development of more representative models of NDs.

The neuroprotective role of CncC in a Drosophila model of Parkinson's disease

Parkinson's disease (PD) is an incurable neurodegenerative disorder, yet significant advancements have been made in understanding its etiology. Among the risk factors, exposure to neurotoxins plays the greatest role. One of the most dangerous toxins is rotenone, a naturally derived compound that was historically used as an insecticide. This chemical affects mitochondrial function by blocking electron transfer, resulting in increased reactive oxygen species production and accumulation. Recently, the role of the Nrf2 pathway was explored as a possible protective mechanism to minimize the neurotoxic effects leading to Parkinson's disease. Here, we used Drosophila melanogaster as a model to examine the link between the expression or activity levels of CncC (an ortholog of Nrf2) or HO (an ortholog of HO-1) in the brain and the detrimental effects of chronic exposure to rotenone. We found that flies with overexpression of CncC or silencing of ho survived better after exposure to rotenone compared with flies with partially suppressed CncC or upregulated ho expression. These experimental groups exposed to rotenone also exhibited significantly fewer degenerated dopaminergic (DA) neurons than did the wild-type group. Nevertheless, only those in which CncC was overexpressed in glia showed the best survival, the greatest percentage of climbing ability, and no effects on DA neurons. Our findings were supported by data obtained for flies fed with HO inhibitor (SnPPIX) or activator (hemin), as well as with curcumin (Nrf2 activator). The observed effects were connected with changes in autophagy and apoptosis pathways. Our data suggest that possible therapies exploiting Nrf2 activation should include restricting HO upregulation as a neuroprotective strategy against the toxic effects of rotenone.

Recent developments in gene therapy for Parkinson's disease

Parkinson's disease (PD) is a progressive, neurodegenerative disorder for which there is currently no cure. Gene therapy has emerged as a novel approach offering renewed hope for the development of treatments that meaningfully alter the course of the disease. In this review, we explore various gene therapy strategies currently being developed targeting key aspects of PD pathogenesis: the restoration of the dopamine system by delivering genes involved in dopamine biosynthesis, reinforcing the inhibitory signaling pathways through glutamic acid decarboxylase (GAD) delivery to increase GABA production, enhancing neuronal survival and development by introducing various neurotrophic factors, delivery of genes to complement recessive familial PD mutations to correct mitochondrial dysfunction, restoring lysosomal function through delivery of GBA1 to increase glucocerebrosidase (GCase) activity, and reducing α-synuclein levels by reducing or silencing SNCA expression. Despite promising early work, challenges remain in developing safe, effective, and long-lasting gene therapies. Key considerations include optimizing viral vectors for targeted delivery, achieving controlled and sustained gene expression using different promoters, minimizing immune responses, and increasing transgene delivery capacity. Future prospects may involve combinatory strategies targeting multiple pathways, such as multi-gene constructs delivered via high-capacity viral systems.

Sex differences in peripheral and central dysregulation of the kynurenine pathway in Parkinson's disease

We previously demonstrated that kynurenine pathway (KP) dysregulation associates with Parkinson's disease (PD) and its symptoms. Here, we profiled 16 KP-related markers in a second, independent cohort; plasma: n = 202 (116 PD ("OFF"), 86 controls); CSF: n = 183 (108, 75). Consistent with previous findings, we detected significantly higher concentrations of neurotoxic 3-hydroxykynurenine in plasma and lower concentrations of neuroprotective kynurenic acid along with higher neurotoxic quinolinic acid/kynurenic acid ratios in CSF of PD patients. Additionally, 10 markers showed sex-based differences, with more pronounced dysregulation in females. These 10 markers loaded to a single principal component linked to higher UPDRS I and II scores. Together, this suggests a composite signature of KP dysregulation in PD that is associated with worse symptoms and more prevalent in women. This work shows that KP dysregulation in peripheral and central compartments is linked to symptom severity in PD and warrants further systematic studies unraveling sex-dependent metabolic differences.

Effect of hydrogen sulfide on alpha-synuclein aggregation and cell viability

Parkinson's disease (PD) is a progressive neurodegenerative movement disorder characterized by nigrostriatal degeneration and aggregation of α-synuclein (α-Syn) with accumulation of insoluble aggregates in Lewy bodies. Familial mutations in α-Syn are associated with the development of PD. Accumulation of insoluble aggregates results in neuronal toxicity. Identification of compounds that inhibit seeding activity of α-Syn is of great importance. Here we investigate the potential of H2S donor, sodium hydrosulfide (NaHS), to inhibit α-Syn aggregation. We examined the effect of NaHS on fibril growth kinetics and the structural change of α-Syn fibrils formed by self-seeding and cross-seeding of wild-type (wt) and PD familial α-Syn mutations. NaHS slowed both self- and cross-seeded A53T α-Syn fibril formation but not wild-type fibril formation. We observed a decrease in the formed fibril length in vitro. We examined the effect on fibril formation within cells. NaHS significantly reduced the number and filament length of formed oligomers in an α-Syn overexpressing cell model. Furthermore, NaHS rescued viability of A53T α-Syn overexpressing cells seeded with wt- and mutant preformed fibrils. These results support a conformation-specific effect of hydrogen sulfide on alpha-synuclein aggregation and cell viability which deserves further exploration for therapeutic potential.

Burden of Parkinson's disease in Iran: disparities, trends, and the impact of social development indicators

BACKGROUND

The burden of Parkinson's disease (PD) and its provincial trends in Iran remain unknown. Herein, we explore PD data from the Global Burden of Disease (GBD) study nationally and provincially from 1990 to 2021.

METHODS

We used age-standardized incidence (ASIR), prevalence (ASPR), and mortality (ASMR) rates to determine disparities and trends overall and by sex, age, and geographic locations. Univariate analysis and regression were performed to scrutinize the mean differences and associations between socioeconomic factors and different PD outcomes.

RESULTS

The ASIR and ASPR of PD increased by 23.1% and 33.2%, respectively, from 1990 to 2021, with estimated total percentage change (TPC) of 0.50 (95%CU: 0.58-0.43) and 0.30 (0.37-0.24), respectively. In 2021, East Azarbayejan had the highest ASIR and ASPR. From 1999 to 2021, the ASMR decreased significantly across individuals aged below 85 years nationally. Overall, 71.0% provinces experienced a downward trend in the ASMR, with the highest decrease in the TPC (-0.21,-0.37-0.01) occurring in Markazi. Significant differences in the PD outcomes between males and females were noted (P < 0.05). There was a significant positive association between the ASPR and the human development index (HDI), urbanization rate, and annual income per rural households.

CONCLUSION

From 1999 to 2021, the incidence and prevalence of PD in Iran and its provinces increased significantly regardless of age and sex classification. Intervention and screening programs should continue to reduce mortality from PD in Iran, but with different priorities between provinces.

The relationship between serum GDF15 levels and non-motor symptoms in Parkinson's disease

OBJECTIVES

The primary aim was to investigate the relationship between serum growth differentiation factor-15 (GDF15) levels and non-motor symptom (NMS) in Parkinson's disease (PD) patients. The secondary aim was to explore the diagnostic value of GDF15 for specific NMS.

METHODS

A total of 102 PD patients were enrolled in this study, including 47 males and 55 females. Doctors collected the clinical and demographic information of patients and detected the level of serum GDF15. Next, linear univariate and multivariate linear regression analyses were used to assess the correlation between GDF15 and NMS. Receiver operating characteristic curve analysis was performed to determine the optimal cut-off value of GDF15 and evaluate its diagnostic value.

RESULTS

In PD patients, there was no significant difference in serum GDF15 levels between males and females (p = 0.831). Age of PD onset, pesticide use, depression, sexual dysfunction, Epworth Sleepiness Scale (ESS) and Hamilton Depression Scale (HAMD) were associated with serum GDF15. Serum GDF15 was negatively correlated with HAMD, depression and sexual dysfunction and positively correlated with ESS. Each 10 pg/ml increase in serum GDF15 levels was associated with a 4% lower risk of depression and a 5% lower risk of sexual dysfunction. Notably, serum GDF15 may be a biomarker for distinguishing depression and sexual dysfunction in PD patients.

CONCLUSION

Elevated serum GDF15 reduced the risk of PD with depression and sexual dysfunction. Serum GDF15 may be a biomarker for distinguishing depression and sexual dysfunction in PD patients.

IgD-CD38-B Cell Partially Mediates the Protective Effect of Higher Serum Triacylglycerol (53:4) Levels Against Parkinson's Disease

Emerging evidence suggests that dysregulated lipid metabolism contributes to Parkinson's disease (PD) risk, with chronic inflammation in the central nervous system (CNS) also playing a pivotal role. Although correlations between inflammatory responses, serum lipid metabolism, and PD risk are established, a causal relationship remains unclear. Building on previous findings linking higher serum triacylglycerol (51:4) levels to reduced PD risk, this study explores the potential causal associations between 38 triacylglycerol isoforms and PD risk using Mendelian randomization (MR). We utilized summary-level data from genome-wide association studies (GWAS) on PD, circulating immune cells, inflammatory proteins, and serum lipidomes-including 38 triacylglycerol isoforms, 15 sterol ester isoforms, and 46 phosphatidylcholine isoforms-to assess the relationship between serum lipid profiles and PD. Our analysis revealed that higher levels of serum triacylglycerol (51:4) and triacylglycerol (53:4) were associated with a reduced PD risk, whereas lower levels of phosphatidylcholine (17:0_18:1) and sterol ester (27:1/20:2) were linked to higher PD risk. Notably, multivariable MR analysis confirmed a robust causal association between increased serum triacylglycerol (53:4) and a 24% reduction in PD risk (1 SD higher triacylglycerol (53:4) leading to a 24% [95% CI, 0.54-0.97] risk reduction, p = 0.005). Mediation analysis suggested that circulating immune cells, rather than inflammatory proteins, may mediate the relationship between triacylglycerol (53:4) levels and PD risk. These findings establish a causal link between triacylglycerol (53:4) and PD risk, highlighting the potential role of immune modulation in PD pathogenesis.

Examining the Relationship Between Physical Function and Anxiety/Depression in Parkinson's

BACKGROUND

Parkinson's disease (PD) is a complex neurological disorder characterized by both motor and nonmotor symptoms, including tremor, muscle stiffness, anxiety, and depression.

OBJECTIVES

The primary aim of this study was to examine the relationship between physical function and psychological symptoms, specifically anxiety and depression, in people with Parkinson's (PwP). The secondary aim was to explore whether any discrepancies between participant-reported and clinician-rated measures of physical function exist.

METHODS

This study utilized the Parkinson's Progression Markers Initiative (PPMI) dataset, analyzing data from 1065 individuals with PD. Correlational analyses assessed relationships between clinician-rated and participant-reported motor outcomes alongside psychological symptoms. Multiple linear regression (MLR) was employed to identify predictors of anxiety and depression.

RESULTS

In PwP, significant correlations were found between depression/anxiety and participant-reported motor function (via MDS-UPDRS Part II: r = 0.313 for depression, r = 0.284 for anxiety, p < 0.05). In contrast, correlations with clinician-rated motor function (via MDS-UPDRS Part III) were weaker (r = 0.079 for depression, p < 0.05; r = 0.054 for anxiety, p = 0.08). MLR analysis indicated that in PwP, age, cognition, and participant-reported motor function explained 11.2% of the variance in depression and 10.5% in anxiety.

CONCLUSIONS

This study highlights a discrepancy between psychological symptoms and their relationship with clinician-rated versus participant-reported motor function in PwP. Our findings suggest that factors such as age, cognitive level, and perceived physical function significantly influence this relationship. Consequently, it is crucial to consider psychological factors and participant-reported motor function when conducting clinical assessments and treatment planning for individuals with PD.

The third wheel or the game changer? How AI could team up with neurologists in Parkinson's care

INTRODUCTION

Parkinson's disease (PD) is a progressive neurodegenerative disorder marked by diverse motor and non-motor symptoms. AI appears to be the elephant in the neurologist's room, albeit offering transformative potential in early diagnosis, personalized care, and treatment optimization, addressing the complexities of PD management.

METHODS

A PubMed review analyzed AI's role in PD care, focusing on multimodal data, clinician-in-the-loop models, and validation strategies to enhance clinical applicability while addressing ethical concerns.

RESULTS

Thirty-nine studies met inclusion criteria. While progress is evident, challenges include limited independent validation, small sample sizes, and inconsistent clinician involvement. Key trends show growing interest in multimodal data and predictive modelling, though gaps in transparency persist.

CONCLUSIONS

AI holds promise for improving PD management, yet robust validation, interdisciplinary collaboration, and clearer clinician roles are essential for advancing patient-centered care and fostering trust in AI-driven innovations.

Neurogrit Gold Attenuates 6-OHDA-Induced Dopaminergic Neurodegeneration in Parkinson's Model of Caenorhabditis elegans by Reducing α-Synuclein Accumulation and Pink/Pdr-1 Driven Mitochondrial Dysfunction

INTRODUCTION

Parkinson's disease (PD) is a neurodegenerative disorder majorly associated with movement and behavioral disturbances. Pathologically, the loss of dopaminergic (DA) neurons triggered by the deposition of α-synuclein (SNCA) leads to the decrease in dopamine levels affecting motor and cognitive functions of the brain. Current pharmacotherapy for PD only addresses its symptoms but is not able to halt its progression. Traditional medicines are being increasingly used for the treatment of neurodegenerative disorders.

AIM

The present study investigated the effects of Neurogrit Gold (NG), a herbo-mineral prescription medicine, on a Parkinson's model of Caenorhabditis elegans.

METHODS

Chemical characterization of NG was performed on HPLC and GC-MS/MS platforms. Evaluation of NG was done in the neurotoxicant 6-OHDA-induced N2, BZ555, and NL5901 strains of C. elegans.

RESULTS

It was observed that NG treatment did not hamper the lifespan, survival, and progeny development of C. elegans strains. The worms treated with NG were able to resist the deleterious effects of 6-OHDA on survival, progeny development, body bends, and chemotaxis in N2 and DA neuron degeneration in BZ555 worms. In NL5901 worms, NG treatment reduced SNCA aggregation, restored lipid content, as well as improved body bends, chemotaxis, and food uptake. Gene expression studies on 6-OHDA exposed and NG-treated N2 worms suggest that the neuroprotective effects of NG stem from its ability to regulate genes involved in mitochondrial autophagy (pink-1, pdr-1); dopamine synthesis (cat-2); redox (sod-3) and protein folding homeostasis (hsf-1, hsp-12.3).

CONCLUSION

Neurogrit Gold has robust neuroprotective effects, making it a suitable treatment option against etiologies of Parkinson's disease.

Clinical predictors of freezing of gait in patients with Parkinson's disease: A systematic review

BACKGROUND

Freezing of gait (FOG) is a debilitating motor symptom of Parkinson's disease (PD) that markedly impacts patients' quality of life. This review aims to identify clinical predictors of FOG to facilitate early prediction and future interventions.

METHODS

A systematic review adhering to PRISMA guidelines was conducted. Comprehensive searches in PubMed, EBSCO, and Web of Science yielded 1761 records. After removing duplicates, 1558 records were screened by title and abstract, and 92 full-text articles were assessed. Nine studies met the inclusion criteria and were qualitatively synthesized.

RESULTS

Our systematic review indicates that higher baseline MDS-UPDRS scores, which reflect greater disease severity, alongside elevated doses and early use of levodopa, are predictive of FOG in patients with PD. Additionally, higher Postural Instability and Gait Disorder (PIGD) scores, motor fluctuations, and lower limb disease onset further increase the risk of FOG. Other factors associated with an increased risk of FOG include older age, longer disease duration, anxiety, hyposmia, cognitive deficits, and sleep disorders. Furthermore, decreased step initiation duration when using visual cues serves as a predictor for the development of FOG. Early treatment with amantadine, selegiline, and dopamine agonists may help reduce the risk of developing FOG.

CONCLUSION

A combination of motor and non-motor factors predicts the development of FOG. Understanding FOG predictors is crucial for developing future therapeutics and personalized management plans, enabling targeted interventions and improved outcomes.

The Regional Burden of Parkinson's Disease in Kazakhstan 2014-2021: Insights From National Health Data

Background: This study explores the burden of Parkinson's disease (PD) in Kazakhstan, the largest country in Central Asia, a region where data on neurological disorders are notably sparse. Methods: Utilizing data from Kazakhstan's Unified National Electronic Health System during 2014-2021, the study investigates the epidemiology, disability-adjusted life years (DALYs), and survival outcomes in a cohort of PD patients. The authors employed Cox proportional hazards regression models and Kaplan-Meier analysis, alongside sensitivity analyses, to assess the impact of demographic factors, hypertension, and the Charlson Comorbidity Index (CCI) on survival. Results: The study cohort included 10,125 patients, revealing a tenfold increase in PD prevalence during the study period. Mortality rates varied significantly, with the highest rates observed in the eldest age group (137.05 per 1000 person-years). PD contributed to a loss of 156.12 DALYs per 100,000 population, primarily driven by years of life lost. The analysis identified an increased risk of all-cause mortality among males (adjusted hazard ratio (aHR) 1.6; 1.5-1.8), older individuals (aHR 1.05; 1.04-1.06), those with higher CCIs, and individuals of Kazakh ethnicity. Interestingly, patients with comorbid hypertension had a higher probability of survival (aHR 0.67; 0.60-0.73). Conclusion: This study is the first of its kind in Central Asia to examine the burden of PD using a large-scale outpatient registry. The findings underscore the need for targeted interventions to address the growing burden of PD, particularly among males and ethnic Kazakhs. Additionally, further research is needed to explore the inverse association between hypertension and survival in the PD cohort.

Global burden of Parkinson's disease from 1990 to 2021: a population-based study

OBJECTIVES

Parkinson's disease (PD) has become a public health concern with global ageing. With a focus on PD, this study sought to project its burden and trends at the national, regional and worldwide levels between 1990 and 2021.

STUDY DESIGN

Population-based study.

METHODS

The Global Burden of Disease (GBD) 2021 provided the PD burden data. The GBD data are considered globally and regionally representative, as it integrates multiple data sources and employs standardised estimation methods. The age-standardised rate (ASR) and estimated annual percentage change (EAPC) were used to estimate trends in the incidence, prevalence, mortality and disability-adjusted life years (DALYs) of PD from 1990 to 2021. ASR was used to calculate the EAPCs using a linear regression model. A Bayesian age-period-cohort model was used to predict future trends up to 2046.

RESULTS

Globally, the overall ASR of PD incidence, prevalence, DALYs and mortality increased from 1990 to 2021. The EAPCs were 1.09 (95% CI: 1.07 to 1.11) for incidence, 1.52 (95% CI: 1.49 to 1.54) for prevalence, 0.32 (95% CI: 0.28 to 0.36) for DALYs and 0.18 (95% CI: 0.13 to 0.23) for mortality. The incidence, prevalence, mortality and DALYs of PD in 2021 were higher in men than in women. The age-standardized incidence rate (ASIR) was 18.52 per 100 000 in men and 12.92 per 100 000 in women (EAPC: 1.11, 95% CI: 1.09 to 1.13 vs 1.07, 95% CI: 1.05 to 1.09). The age-standardized prevalence rate (ASPR) was 157.42 per 100 000 in men and 121.84 per 100 000 in women (EAPC: 1.70, 95% CI: 1.67 to 1.73 vs 1.25, 95% CI: 1.22 to 1.27). The ASMR was 6.57 per 100 000 in men and 3.59 per 100 000 in women (EAPC: 0.21, 95% CI: 0.14 to 0.28 vs -0.01, 95% CI: -0.04 to 0.03). The ASDR was 97.12 per 100 000 in men and 81.23 per 100 000 in women (EAPC: 0.37, 95% CI: 0.33 to 0.42 vs 0.14, 95% CI: 0.10 to 0.18). From 1990 to 2021, the burden of PD remained consistently higher in men than in women, with the gender difference widening with age. The prevalence, incidence, DALYs and mortality rates of PD increased with age before declining, peaking in the 80-84 age group for prevalence and incidence, while peaking in the 90-94 age group for mortality. DALY rates peaked in the 85-89 age group. The ASR of incidence and prevalence increased significantly in Norway (EAPC=3.39, 95% CI: 3.15 to 3.64; EAPC=5.04, 95% CI: 4.65 to 5.43). Lesotho was the nation with the highest rise in age-standardised DALYs for PD (EAPC=1.67, 95% CI: 1.41 to 1.93). The United Arab Emirates had the fastest increase in age-standardised mortality for PD (EAPC=1.98, 95% CI: 1.24 to 2.71). The global ASPR of PD is projected to show a continuous upward trend.

CONCLUSIONS

From 1990 to 2021, there were rising trends in the prevalence and burden of PD in most areas and nations worldwide. Our research indicates that the management and control of PD need significant improvement, particularly in light of the ageing population.

Urolithin improves α-synuclein aggregation and DNMT1 expression in rotenone model of Parkinson's disease

α-synuclein aggregation is a key hallmark of Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). We examined the multi-targeting effects of urolithin (UA, UB, UC, UD, UE, UM5, and UM6) against α-synuclein aggregation using an in-silico and in-vitro approach. For in-silico analysis, several potential targets were selected like 1XQ8 (α-synuclein monomer), 1H1D (catechol-o-methyltransferase), 2BK3 (monoamine oxidase-B), 3IAM (NADH dehydrogenase), 4I5I (Sirtuin-1), and 5WVO [DNA methyltransferase-1], which play key role in α-synuclein aggregation, levodopa degradation, and mitochondrial dysfunction. In protein-protein docking analysis, 5HF9 (acetylcholinesterase, AChE) was found to interact with 1XQ8 dimer, forming a more stable complex with two additional H-bonds and one salt bridge, which indicates AChE's role as a nucleator in α-synuclein aggregation. In ligand docking and molecular dynamic studies, urolithin-A (UA) formed a more stable complex with 1XQ8, 4I5I, and 5WVO compared to specific inhibitor 1XQ8-ZPD2 and specific activator 4I5I-resveratrol. While other urolithins (UE, UM5, UC, and UD) displayed a more stable complex with 5HF9, 2BK3, 1H1D, and 3IAM compared to specific inhibitor 5HF9-physostigmine, 2BK3-selegiline, 1H1D-BIA, and specific activator 3IAM-resveratrol complexes, respectively. The blood-brain barrier permeability of UA (QPlogBB: -0.97) was predicted to be more than levodopa (QPlogBB: -1.44) and less than rotenone (QPlogBB: 0.08). DNMT1 inhibitor (5-Aza-dC) and rotenone robustly decreased the DNMT1 and α-synuclein expression in Neuro 2 A cells which was significantly reversed by UA treatment at 31.25 µM concentration. These findings indicate the potential of urolithins, specifically UA, UC, UD, UE, and UM5 against α-synuclein aggregation.

MIRO1 mutation leads to metabolic maladaptation resulting in Parkinson's disease-associated dopaminergic neuron loss

MIRO1 is a mitochondrial outer membrane protein important for mitochondrial distribution, dynamics and bioenergetics. Over the last decade, evidence has pointed to a link between MIRO1 and Parkinson's disease (PD) pathogenesis. Moreover, a heterozygous MIRO1 mutation (p.R272Q) was identified in a PD patient, from which an iPSC-derived midbrain organoid model was derived, showing MIRO1 mutant-dependent selective loss of dopaminergic neurons. Herein, we use patient-specific iPSC-derived midbrain organoids carrying the MIRO1 p.R272Q mutation to further explore the cellular and molecular mechanisms involved in dopaminergic neuron degeneration. Using single-cell RNA sequencing (scRNAseq) analysis and metabolic modeling we show that the MIRO1 p.R272Q mutation affects the dopaminergic neuron developmental path leading to metabolic deficits and disrupted neuron-astrocyte metabolic crosstalk, which might represent an important pathogenic mechanism leading to their loss.

Optimized use of safinamide as an add-on therapy in Asian patients with Parkinson's disease: a narrative review and expert opinion

Parkinson's disease (PD) imposes a large burden on Asian countries and threatens to grow rapidly as Asian populations age. PD phenotypes in Asian patients differ from those reported in the West, yet management generally follows a similar approach. Levodopa (l-dopa) is a mainstay of therapy and is typically followed by the addition of a catechol-O-methyltransferase inhibitor or a monoamine oxidase-B (MAO-B) inhibitor to address the wearing-off effect. There is little guidance on switching between MAO-B inhibitors or other adjunct therapies that consider the newer evidence for safinamide as an add-on PD therapy in Asian patients. Therefore, a group of PD experts in Asia evaluated the evidence supporting safinamide for the treatment of PD with a focus on integrating this treatment option into local clinical practice. A narrative review was conducted to identify supportive evidence for the formulation of summary statements on key topics. The efficacy and safety of safinamide added to l-dopa in Asian patients with PD are supported by both clinical trials and observational data, including two randomized trials enrolling exclusively Asian patients (n = 406; n = 307) and an Asian subpopulation analysis from another randomized trial (n = 173). Safinamide reduces wear-off duration and has beneficial effects on motor symptoms of PD, with good tolerability outcomes. Safinamide may also have beneficial effects on non-motor symptoms of PD such as urinary symptoms, apathy and sleep disturbances, and it is a suitable treatment for older patients. Overall, safinamide is an effective and well-tolerated treatment for the wear-off effect of l-dopa in Asian patients and, during long-term treatment, might reduce the risk of dyskinesia in patients without pre-existing dyskinesia. Additional research is needed to better understand the role of safinamide for patients with fluctuating pain, the dose-effect relationship of safinamide in Asian patients and the efficacy of safinamide in Asian patients with early-onset PD.

Ginsenoside Rg1 in Parkinson's disease: from basic research to clinical applications

This review provides an in-depth exploration of the potential of Ginsenoside Rg1 in the treatment of Parkinson's disease (PD). The emphasis of this article was the therapeutic mechanisms of Rg1, which involved the reduction of inflammation, antioxidant properties, support for neuronal survival and regeneration, regulation of cellular energy processes, and enhancement of autophagic pathways. Rg1 may protect neurons and improve both motor and cognitive impairments associated with PD through multiple mechanisms. However, challenges exist in the clinical application of Rg1, such as low bioavailability as well as a lack of comprehensive long-term safety and efficacy data. This article also reviewed network pharmacology analyses published previously to identify and explore the potential molecular targets of Rg1 in PD treatment, while evaluating strategies such as drug delivery technologies, optimizing administration routes, and combination therapies. Ultimately, this review highlights the necessity for large-scale clinical trials to validate the clinical efficacy of Rg1 and discusses its potential for PD treatment clinically.

Distinct expression of NEAT1 isoforms in Parkinson's disease models suggests different roles of the variants during the disease course

Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide. Recently long non-coding RNAs (lncRNAs) have emerged as possible molecular hubs in the diverse pathomechanisms of the disease. Among them, NEAT1 gained particular interest due to findings suggesting both protective and deleterious effects of this lncRNA in PD models.The aim of this study was to clarify some of the contradictions among data that appeared in recent publications concerning NEAT1 effects. For this, we determined whether pharmacological increase of NEAT1 levels worsened the detrimental effect of MPP + in the SH-SY5Y cell model, and whether the levels of the short and long isoform of the lncRNA changed differently upon short and extended MPTP treatment in an MPTP-induced mouse model of PD. Our findings suggest differential expression of NEAT1/Neat1 isoforms in MPP + /MPTP-induced PD models, which is in accord with the proposed role of the lncRNA in the general stress response. We propose that first an early up-regulation of Neat1_2 is dominant. The level of Neat1_2 then decreases as pathology progresses, resulting in a shift in the ratio of the two isoforms towards a higher level of Neat1_1 accompanied by damage of the central nervous system.

Role of Antioxidants in Modulating the Microbiota-Gut-Brain Axis and Their Impact on Neurodegenerative Diseases

This narrative review presents the role of antioxidants in regulating the gut microbiota and the impact on the gut-brain axis, with a particular focus on neurodegenerative diseases, such as Alzheimer's (AD) and Parkinson's disease (PD). These diseases are characterised by cognitive decline, motor dysfunction, and neuroinflammation, all of which are significantly exacerbated by oxidative stress. This review elucidates the contribution of oxidative damage to disease progression and explores the potential of antioxidants to mitigate these pathological processes through modulation of the gut microbiota and associated pathways. Based on recent studies retrieved from reputable databases, including PubMed, Web of Science, and Scopus, this article outlines the mechanisms by which antioxidants influence gut health and exert neuroprotective effects. Specifically, it discusses how antioxidants, including polyphenols, vitamins, and flavonoids, contribute to the reduction in reactive oxygen species (ROS) production and neuroinflammation, thereby promoting neuronal survival and minimising oxidative damage in the brain. In addition, the article explores the role of antioxidants in modulating key molecular pathways involved in oxidative stress and neuroinflammation, such as the NF-κB, Nrf2, MAPK, and PI3K/AKT pathways, which regulate ROS generation, inflammatory cytokine expression, and antioxidant responses essential for maintaining cellular homeostasis in both the gut and the central nervous system. In addition, this review explores the complex relationship between gut-derived metabolites, oxidative stress, and neurodegenerative diseases, highlighting how dysbiosis-an imbalance in the gut microbiota-can exacerbate oxidative stress and contribute to neuroinflammation, thereby accelerating the progression of such diseases as AD and PD. The review also examines the role of short-chain fatty acids (SCFAs) produced by beneficial gut bacteria in modulating these pathways to attenuate neuroinflammation and oxidative damage. Furthermore, the article explores the therapeutic potential of microbiota-targeted interventions, including antioxidant delivery by probiotics and prebiotics, as innovative strategies to restore microbial homeostasis and support brain health. By synthesising current knowledge on the interplay between antioxidants, the gut-brain axis, and the molecular mechanisms underlying neurodegeneration, this review highlights the therapeutic promise of antioxidant-based interventions in mitigating oxidative stress and neurodegenerative disease progression. It also highlights the need for further research into antioxidant-rich dietary strategies and microbiota-focused therapies as promising avenues for the prevention and treatment of neurodegenerative diseases.

Pesticide exposure and the development of Parkinson disease: a systematic review of Brazilian studies

Parkinson disease is the second most prevalent neurodegenerative disease globally. Parkinson disease etiology is not fully understood, it is believed to be a multifactorial disease. Pesticide exposure is highlighted among the factors. Thus, this study analyzed the relationship between pesticide exposure and the development of Parkinson disease in Brazil via a systematic review. The review was conducted following the PRISMA methodology and PICOS process, using the PubMed, Web of Science, and Virtual Health Library databases. Inclusion criteria were observational studies, conducted in humans, focusing on the Brazilian population, and investigating the relationship between pesticide exposure and Parkinson disease development. Studies quality was evaluated using the Hawker checklist. A total of 85 publications were identified for eligibility and 12 studies were included in the qualitative synthesis. Regarding study quality, two showed poor, nine moderate, and only one presented high quality. Moreover, 11 studies indicated an association between pesticide exposure and increased occurrence of Parkinson disease in Brazilian people. Additionally, such association was more prevalent in the presence of the following factors: (i) single-nucleotide polymorphism IVS1-7 A→G of PINK1; (ii) variations in the gene and protein expressions of the enzyme glutathione S-transferase; (iii) occupational exposure; (iv) living in a non-urban area; (v) low schooling level, and (iv) being male. This study is the first to infer, via the systematization of observational studies conducted with the Brazilian population, the association between pesticide exposure and the occurrence of Parkinson disease in the country, evidencing the necessity of efficient public policies.

A case-control study on vitamin D receptor gene polymorphisms in patients with Parkinson's disease in Bangladesh

Parkinson's disease (PD) is a neurodegenerative disorder with a multifactorial etiology. This study aimed to investigate the association between vitamin D receptor (VDR) gene polymorphisms (ApaI, BsmI, FokI and TaqI) and the risk of PD in a Bangladeshi population. A case-control study was conducted with 100 PD patients and 100 age- and sex-matched healthy controls. Serum vitamin D levels were measured using a chemiluminescent immunoassay, and VDR gene polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Genetic models (allele, dominant, recessive and additive models) were used to assess the association between each polymorphism and PD risk. The mean age of the patients with PD was 63 years, with 65% being male, while the control group had a mean age of 54.5 years and 60% were male. In genetic models, the T allele of the ApaI gene demonstrated a significant association with PD (OR 1.92, 95% CI 1.20-3.13, p-value 0.007). This significant association persisted across both recessive and additive models (for recessive model: OR 2.17, 95% CI 1.10-4.55, p-value 0.027 and for additive model: OR 2.78, 95% CI 1.22-6.67, p-value 0.015). Similarly, the T allele of the FokI gene was found to be significantly associated with PD (OR 2.27, 95% CI 1.43-3.57, p-value 0.001). This association was also evident in both dominant and additive models (for dominant model: OR 2.56, 95% CI 1.45-4.55, p-value 0.001 and for additive model: OR 3.03, 95% CI 1.67-5.56, p-value 0.001). Conversely, no significant associations were observed for the genetic polymorphisms of the BsmI and TaqI genes across any of the genetic models examined. The findings suggest that specific VDR gene polymorphisms, particularly ApaI and FokI, are significantly associated with the risk of PD in the Bangladeshi population.

Knowledge of Parkinson's disease among non-PD specialists: a web-based survey in South China

Background

Parkinson's disease (PD) is a prevalent, disabling neurodegenerative disorder. Early diagnosis and treatment of PD remains challenging due to the absence of definitive diagnostic tests and the non-specificity of its clinical manifestations. Initial consultations for PD symptoms often involve specialists who are not specifically trained in PD. Consequently, it is imperative to assess the general knowledge regarding PD among these specialists to develop optimal educational strategies and enhance early recognition and diagnosis of PD.

Methods

We developed a questionnaire covering motor symptoms, non-motor symptoms, prodromal symptoms, risk factors and antiparkinsonian medications based on published guidelines, and conducted the web-based survey via Wenjuan xing (https://www.wjx.cn/) among physicians not specializing in PD in Guangdong Province, China.

Results

A total of 312 respondents, working in 28 diverse departments across 64 hospitals of three different categories, were eligible for data analysis. Notably, 95.2% of the respondents were aware of rest tremor as a motor symptom, yet only 76.9% recognized bradykinesia as a motor symptom. Regarding non-motor symptoms, erectile dysfunction, urinary dysfunction, restless legs, olfactory loss, orthostatic hypotension, rapid eye movement behavior disorder (RBD), lower back pain and diaphoresis, were recognized by less than 50% of the respondents. Additionally, with the exception of subthreshold parkinsonism or abnormal quantitative motor testing, prodromal symptoms such as excessive daytime somnolence, depression (± anxiety), olfactory loss, urinary dysfunction, RBD, and constipation were recognized by 36.5-48.7% of the respondents. First-degree relatives with PD received recognition from 86.5% of the respondents, whereas the remaining risk factors were recognized by 50-60% of the participants. Concerning protective factors for PD, recognition was limited to no more than 23%. Levodopa and dopamine releasers were the most widely recognized antiparkinsonian medications, while the recognition of other medications was below 70%. Variables such as medical degrees, professional titles, hospital categories, and education subjects contributed to statistical differences in PD knowledge.

Conclusion

Among non-PD specialists in south China, current knowledge regarding PD, including non-motor symptoms, prodromal symptoms, risk and protective factors, and antiparkinsonian medications, is relatively inadequate. This necessitates targeted education and training to improve their understanding and recognition of PD.

Active group-based performing arts interventions in Parkinson's disease: an updated systematic review and meta-analysis

OBJECTIVES

To assess the evidence for active group-based performing arts interventions for people with Parkinson's disease (PD).

SETTING

Scholarly literature (published in English) from any country or countries (last search February 2025). This systematic review was not registered and received no funding.

DATA SOURCES

Five bibliographic databases: AMED (Ebsco), APA PsycINFO (Ovid), CINAHL (Ebsco), EMBASE (Ovid) and MEDLINE (Ovid), plus supplementary searches.

PRIMARY AND SECONDARY OUTCOME MEASURES

Eligible studies used a quantitative design to assess the benefit of active group-based performing arts interventions on quality of life, functional communication, speech, motor function and cognitive status in PD. The risk of bias was assessed using the SURE, University of York Centre for Reviews and Dissemination and Newcastle-Ottawa Scale checklists. Data were synthesised using narrative synthesis and random-effects meta-analysis.

RESULTS

A total of 94 studies were included: 2453 people with PD (mean age 68 years, 55% male) from 18 countries. Narrative synthesis supported nine combinations of performing arts modalities and outcome domains, including a benefit for dance on motor function (supported by 50 out of 54 studies), dance on quality of life (supported by 24 out of 37 studies) and singing on speech (supported by 17 out of 20 studies). Meta-analysis supported five combinations of performing art modalities, comparators and outcomes, including a clinically significant benefit for PD-specific dance versus usual care PDQ-39, MD -7.81, 95% CI -11.87 to -3.75 and tango-based dance versus usual care on UPDRS-III, MD -9.89, 95% CI -16.65 to -3.13.

CONCLUSIONS

Evidence from both the narrative synthesis and the meta-analysis supports a benefit for some combinations of performing arts modalities and outcomes. Limitations of the evidence base included differences in comparators and outcomes, heterogeneity, lack of control arms and male underrepresentation. Future studies should compare the effectiveness of different performing arts modalities, assess functional communication and consider clinical significance.

Nature's Remedies: Exploring the Potential of Propolis to Alleviate Non-Motor Manifestations of Parkinson's Disease

Parkinson's disease (PD) is a complex neurodegenerative disorder with debilitating non-motor symptoms, including gastrointestinal dysfunction, cardiovascular abnormalities, mood and anxiety disorders, cognitive decline, sleep disturbances, respiratory dysfunction, and pain. Despite their significant impact on quality of life, these symptoms are often inadequately addressed. Propolis is a natural bee-derived product, rich in bioactive compounds with anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective properties, which holds potential in PD due to its multitarget and multipathway actions, addressing various underlying mechanisms of non-motor symptom diseases. Preclinical and clinical studies suggest that propolis may influence key pathological mechanisms in PD's non-motor symptoms. Evidence points to its potential benefits in improving cognition, mood disorders, gastrointestinal health, and alleviating cardiovascular and sleep-related issues. Although research on propolis in non-motor symptoms of PD remains scarce, findings from related conditions suggest its ability to influence mechanisms associated with these symptoms. This review underscores the underexplored therapeutic potential of propolis in non-motor symptoms of PD, drawing on existing evidence and advocating for further research to fully assess its role in addressing these symptoms and improving patient outcomes.

Deletion of the Transient Receptor Potential Melastatin 2 Gene Mitigates the 6-Hydroxydopamine-Induced Parkinson's Disease-Like Pathology

Pharmacological inhibition of the transient receptor potential melastatin 2 (TRPM2), an oxidative stress-activated calcium channel, was previously reported to be protective in Parkinson's disease (PD). However, the inhibitors used were not TRPM2 specific, so the involvement of this channel in PD remains unclear. Here, for the first time, Trpm2 partial (+ / -) and complete (- / -) knockout mice underwent stereotaxic surgery for PD induction. Six-hydroxydopamine was injected in the right striatum. On days 3 and 6, motor behavior tests (cylinder, apomorphine, and pole test) were performed. On day 7, brains were collected for dopaminergic neuron immunostaining. Our results showed that Trpm2 + / - male and female mice had reduced motor impairment and dopaminergic neuron death after PD induction. In addition, Trpm2 - / - male and female mice showed absent or lesser motor deficit and the dopaminergic neuronal loss was no longer observed. These findings suggest that TRPM2 is involved in the PD-like pathology and that targeting TRPM2 may possibly represent a potential neuroprotective strategy for PD.

Global, regional and national temporal trends in Parkinson's disease incidence, disability-adjusted life year rates in middle-aged and older adults: a cross-national inequality analysis and Bayesian age-period-cohort analysis based on the global burden of disease 2021

BACKGROUND

Parkinson's disease (PD) ranks as the second most prevalent neurodegenerative disorder; however, its epidemiological characteristics among middle-aged and older adults at global, regional, and national levels remain inadequately documented.

METHODS

This study assessed temporal trends in PD among middle-aged and older adults by extracting incidence rates, disability-adjusted life year (DALY) rates, and corresponding age-specific rates (ASRs) from the Global Burden of Disease (GBD) database spanning 1990 to 2021. Estimated annual percentage change (EAPC) was employed to analyze trends over the past 30 years. The slope index of inequality (SII) and concentration index (CI) were utilized to evaluate disparities in the burden of PD across various countries. Additionally, Bayesian age-period-cohort (BAPC) modeling was applied to project DALY figures for the next 15 years.

RESULTS

In 2021, the global incidence and DALY rates for middle-aged and older adults with PD stood at 79.68 and 477.50 cases per 100,000 population, respectively. Both incidence and DALY rates have exhibited an upward trajectory over the past 32 years, with EAPCs of 1.2 (95% UI: 1.1-1.3) and 0.6 (95% UI: 0.5-0.7), respectively. Among the five sociodemographic index (SDI) regions, the high-middle SDI region reported the highest incidence and DALY rates for PD in 2021, at 93.93 and 512.29 cases per 100,000 population, respectively. A positive correlation was observed between the SDI and age-specific incidence rate (ASIR) as well as age-specific DALY rate (ASDR). Disparities in the burden of PD among middle-aged and older adults, associated with SDI, are on the rise and are primarily concentrated in high SDI countries. It is projected that the global incidence and DALY rates for middle-aged and older adults with PD will experience significant increases over the next 15 years.

CONCLUSIONS

The global burden of PD among middle-aged and older adults has markedly escalated over the past 32 years, particularly in high-middle SDI regions. These findings underscore the necessity for the development of effective interventions and public health policies, contributing to the attainment of the sustainable development goals established by the World Health Organization (WHO).

Test, track, treat using wearable sensors for management of Parkinson's disease: 12‑month prospective observational United Arab Emirates study using Parkinson's Kinetograph (EmPark-PKG Study)

Parkinson's disease (PD) is a progressive neurodegenerative disorder marked by both motor and non-motor symptoms that necessitate ongoing clinical evaluation and medication adjustments. Home-based wearable sensor monitoring offers a detailed and continuous record of patient symptoms, potentially enhancing disease management. The EmPark-PKG study aims to evaluate the effectiveness of the Parkinson's KinetoGraph (PKG), a wearable sensor device, in monitoring and tracking the progression of motor symptoms over 12 months in Emirati and non-Emirati PD patients. Fifty PD patients (32% Emirati, 68% non-Emirati) were assessed at baseline and a 12-month follow-up. Clinical evaluations included levodopa equivalent daily dosage (LEDD) and motor and non-motor assessments. Concurrently, the PKG provided metrics such as bradykinesia score (BKS) and dyskinesia score (DKS). Statistical analyses were conducted to determine changes from baseline to six months, differences between Emirati and non-Emirati groups, and correlations between PKG metrics and clinical assessments. Significant reductions in LEDD and improvements in both motor and non-motor scores were observed from baseline to six months (p < 0.05). PKG-guided medication adjustments were associated with enhanced motor and non-motor outcomes (p < 0.05). Specifically, non-Emirati patients exhibited a significant reduction in LEDD (Z = - 2.010, p = 0.044), whereas Emirati patients did not (Z = - 0.468, p = 0.640). Both groups showed significant improvements in motor scale scores and motor complication scores. Spearman correlation analysis revealed strong relationships between PKG metrics and subjective clinical assessments (p < 0.001). The EmPark-PKG study demonstrates the potential benefits of remote PKG monitoring for personalised motor symptom management in PD. PKG supports a stepped care paradigm by enabling bespoke medication titration based on objective data, facilitating tailored and effective patient care.

Neuroprotective effect of cedrol in a male rat model of Parkinson's disease

Cedrol is a natural sesquiterpene subgroup of terpenes with antioxidant and anti-inflammatory properties. This study evaluated the effect of cedrol on the 6-hydroxydopamine (6-OHDA) rat model of Parkinson's disease (PD). Unilateral injection of 6-OHDA was performed to induce the PD model. Cedrol at 10 mg/kg and 20 mg/kg was administrated. The rotarod test, apomorphine-induced rotational test, and open field tests assessed motor function, while the passive avoidance test was used to evaluate cognitive function. Furthermore, striatal levels of malondialdehyde (MDA) and total thiol, and SOD (superoxide dismutase) activity were measured. The induction of lesion led to a significantly higher number of rotations in the apomorphine-induced rotational test, lower maintenance in the rotarod test, as well as a shorter delay for entering into and a longer duration of time spent in the dark chamber in the passive avoidance test, versus the control group. It also enhanced the striatal levels of MDA and diminished the striatal SOD activity and level of total thiol. Administration of cedrol significantly improved behavioral tests and biochemical assays. Cedrol could benefit cognitive and motor functions in a rat model of PD. Its antioxidant properties might mediate these effects.

Albiflorin ameliorates neuroinflammation and exerts neuroprotective effects in Parkinson's disease models

BACKGROUND

Albiflorin isolated from Paeoniae Alba Radix can cross the blood-brain barrier (BBB) and possesses analgesia, anticonvulsant, anti-inflammatory, and hepatoprotective properties. This study investigates albiflorin functions and related mechanisms in Parkinson's disease (PD) pathogenesis.

METHODS

Cellular and animal models of PD were constructed. Cell viability and apoptosis were detected by CCK-8 assays. Levels of Iba-1 and TH were measured by immunofluorescence staining, western blotting, and immunohistochemistry staining. Levels of pro-inflammatory mediators and pathway-related genes were measured by western blotting and RT-qPCR. Locomotor activity of mice was examined by open field test, rod climbing test, and rod rotating test.

RESULTS

For in vitro analysis, albiflorin inhibited LPS-induced microglial activation and neuroinflammation. Additionally, albiflorin inactivated NF-κB and MAPK pathways in LPS-treated BV2 cells. Moreover, albiflorin attenuated neurotoxicity mediated by LPS-stimulated microglia. For in vivo analysis, albiflorin improved MPTP-induced locomotor activity deficits and reduced MPTP-induced dopaminergic neuron loss. In parallel, albiflorin inhibited activated microglia-mediated neuroinflammation in MPTP-treated mice.

CONCLUSION

Albiflorin mitigates neuronal apoptosis and improves behavioral impairments in MPTP-induced PD mouse model through inhibition of activated microglia-mediated neuroinflammation via the NF-κB and MAPK pathways.

Exosome-based drug delivery systems for enhanced neurological therapeutics

Exosomes are small extracellular vesicles naturally secreted by cells into body fluids, enriched with bioactive molecules such as RNAs, proteins, and lipids. These nanosized vesicles play a crucial role in physiological and pathological processes by facilitating intercellular communication and modulating cellular responses, particularly within the central nervous system (CNS). Their ability to cross the blood-brain barrier and reflect the characteristics of their parent cells makes exosomal cargo a promising candidate for biomarkers in the early diagnosis and clinical assessment of neurological conditions. This review offers a comprehensive overview of current knowledge on the characterization of mammalian-derived exosomes, their application as drug delivery systems for neurological disorders, and ongoing clinical trials involving exosome-loaded cargo. Despite their promising attributes, a significant challenge remains the lack of standardized isolation methods, as current techniques are often complex, costly, and require sophisticated equipment, affecting the scalability and affordability of exosome-based therapies. The review highlights the engineering potential of exosomes, emphasizing their ability to be customized for targeted therapeutic delivery through surface modification or conjugation. Future advancements in addressing these challenges and leveraging the unique properties of exosomes could lead to innovative and effective therapeutic strategies in neurology.

Global trends and projections of Parkinson's disease incidence: a 30-year analysis using GBD 2021 data

BACKGROUND AND OBJECTIVES

Parkinson's disease (PD) is a neurodegenerative disorder marked by the progressive loss of dopaminergic neurons, leading to motor dysfunction and non-motor symptoms like cognitive decline and depression. With the aging global population, PD incidence is anticipated to rise, especially in regions with rapidly growing elderly populations. This study leverages Global Burden of Disease (GBD) 2021 data to analyze the burden of PD by region, sex, and age group, examining trends from 1992 to 2021 and projecting the future burden to 2030.

METHODS

Data from the GBD 2021 database for the years 1992-2021 were analyzed to assess age-standardized incidence rates (ASIR) and mortality of PD across socio-demographic index (SDI) regions, sex, and age groups. The Age-Period-Cohort (APC) model was used to explore temporal trends, while the Bayesian Age-Period-Cohort (BAPC) model projected future PD burden from 2022 to 2030.

RESULTS

From 1992 to 2021, global PD cases increased from 450,000 to 1.34 million, with crude incidence rates rising from 8.19 to 16.92 per 100,000 and ASIR from 11.54 to 15.63 per 100,000, indicating an annual net drift of 1.11% (95% CI 1.06%-1.17%), reflecting a growing burden driven by an aging population. All SDI regions saw a growth in PD burden, with the highest increases in middle- and high-middle-SDI regions, where male incidence was notably higher than female. Incidence rates escalated sharply in individuals aged 60 and older, peaking in those aged 85 and above. Projections suggest that by 2030, global PD cases will reach 1.93 million, with an ASIR of 27 per 100,000.

DISCUSSION

The findings highlight a sustained global increase in PD burden, particularly in middle- and high-income regions and among men. In low-SDI areas, PD burden may be underestimated due to limited healthcare access and diagnostic challenges. These results stress the urgent need for health policies focused on elderly populations, especially men, and call for effective prevention and intervention strategies to mitigate the future impact of PD.

Immune cell metabolic dysfunction in Parkinson's disease

Parkinson's disease (PD) is a multi-system disorder characterized histopathologically by degeneration of dopaminergic neurons in the substantia nigra pars compacta. While the etiology of PD remains multifactorial and complex, growing evidence suggests that cellular metabolic dysfunction is a critical driver of neuronal death. Defects in cellular metabolism related to energy production, oxidative stress, metabolic organelle health, and protein homeostasis have been reported in both neurons and immune cells in PD. We propose that these factors act synergistically in immune cells to drive aberrant inflammation in both the CNS and the periphery in PD, contributing to a hostile inflammatory environment which renders certain subsets of neurons vulnerable to degeneration. This review highlights the overlap between established neuronal metabolic deficits in PD with emerging findings in central and peripheral immune cells. By discussing the rapidly expanding literature on immunometabolic dysfunction in PD, we aim to draw attention to potential biomarkers and facilitate future development of immunomodulatory strategies to prevent or delay the progression of PD.

Risk of Parkinson's disease in older people with tremor: A population-based prospective study

BackgroundTremor is prevalent among older adults and is suggested to be associated with the subsequent development of Parkinson's disease (PD). However, prospective evidence for the association is scarce.ObjectiveThis population-based prospective study aimed to estimate PD risk and to explore predictive factors for PD conversion in community-dwelling older people with tremor.MethodsThe study was based on the Beijing Longitudinal Study on Aging (BLSA) II. Tremor was assessed using a validated self-administered method. Participants without parkinsonism and with any tremor were followed for an average of 7.7 years. The standardized incidence ratio (SIR) was used to estimate the risk of developing PD in older people with tremor, with age- and sex-specific incidence rates of PD in the general Chinese population as a reference. Risk factors, prodromal symptoms, and tremor features were assessed to identify predictors for incident PD.ResultsSeventeen (8.4%) of 202 participants with tremor developed parkinsonism, including 9 (4.4%) diagnosed with PD. The presence of any tremor was associated with an increased risk of developing PD (SIR: 3.12, 95% confidence interval [CI]: 1.52-5.73). Sensitivity analyses yielded similar results. Probable REM sleep behavior disorder (RBD), identified using the RBD Questionnaire-Hong Kong, and self-report of new-onset rest tremor predicted PD conversion.ConclusionsTremor is associated with an elevated risk of PD in the general older population. Screening for RBD and monitoring the evolution of tremor characteristics using simple questionnaires may help identify individuals at high risk for PD among community-dwelling older adults with tremor.

Modulation of α-Synuclein Fibrillation and Toxicity by 4-Phenylbutyric Acid

The protein misfolding and aggregation of α-synuclein (α-Syn) into neurotoxic amyloids underlies the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD). Emerging evidence suggests that 4-phenylbutyrate (PBA) may play a role as a potential chemical chaperone for targeting α-Syn aggregation, but its molecular mechanism remains largely unknown. Using in vitro assays, we demonstrate that PBA treatment alters the pattern of α-Syn aggregation, as evidenced by reduced formation of oligomeric species and its increased susceptibility to proteolytic cleavage under the influence of PBA. Proteinase K (PK) assays, surface plasmon resonance (SPR), Nile red assays, and cytotoxicity assays indicate that PBA interacts with the extensive hydrophobic contacts of α-Syn oligomers and significantly reduces α-Syn-amyloid-induced toxicity. Furthermore, using thioflavin T-based assays, we elucidated the kinetics of PBA-mediated modulation of α-Syn aggregation, highlighting its role in accelerating the formation of α-Syn amyloid fibrils. Molecular dynamics (MD) simulations suggest PBA's role in the destabilization of the C-terminus in α-Syn oligomers through multiple residue interactions. Collectively, our findings provide compelling evidence for the neuroprotective potential of PBA in targeting protein misfolding and aggregation in PD and suggest an avenue for disease-modifying interventions in neurodegenerative disorders.

The impact of sociodemographic factors and surgical modalities on deep brain stimulation for Parkinson's disease

Background

This study evaluated the impact of sociodemographic factors, surgical modalities, and commercially available options of electrodes on deep brain stimulation (DBS) outcomes in Parkinson's disease.

Methods

We retrospectively analyzed 59 elective DBS surgeries performed at a single institution from 2016 to 2023. Hoehn and Yahr (HY) scale scores and levodopa equivalent daily dosages (LEDD) were assessed at baseline, 3 months, and 6 months postoperatively. Collected variables included length of stay (LOS), age, sex, race/ethnicity, language, body mass index, insurance status, marital status, religion, type of anesthesia, concurrent pulse generator implantation, location of the implant, and conventional or directional lead. DBS systems included Medtronic, Boston Scientific, and Abbott (also known as St. Jude Medical).

Results

The mean LOS was 2.36 days. Mean HY scores improved from baseline (3.17) to 3 months (2.83) and 6 months (2.85), and LEDD significantly decreased at both 3 and 6 months postoperatively. Divorced patients showcased a significantly larger improvement in HY scores at 3 months compared to other marital groups. Abbott leads were associated with a significantly longer LOS compared to Boston Scientific (+1.85 days) and Medtronic (+2 days). No other variables significantly affected DBS outcomes.

Conclusion

This study investigated the impact of sociodemographic factors and surgical modalities of DBS in PD patients, showcasing how DBS improved motor function and reduced medication usage at 3 and 6 months postoperative. Marital status and lead manufacturer significantly influenced DBS outcomes, highlighting the importance of personalized considerations in DBS management.

Brain Cytochrome P450: Navigating Neurological Health and Metabolic Regulation

Human cytochrome P450 (CYP) enzymes in the brain represent a crucial frontier in neuroscience, with far-reaching implications for drug detoxification, cellular metabolism, and the progression of neurodegenerative diseases. The brain's complex architecture, composed of interconnected cell types and receptors, drives unique neuronal signaling pathways, modulates enzyme functions, and leads to distinct CYP gene expression and regulation patterns compared to the liver. Despite their relatively low levels of expression, brain CYPs exert significant influence on drug responses, neurotoxin susceptibility, behavior, and neurological disease risk. These enzymes are essential for maintaining brain homeostasis, mediating cholesterol turnover, and synthesizing and metabolizing neurochemicals, neurosteroids, and neurotransmitters. Moreover, they are key participants in oxidative stress responses, neuroprotection, and the regulation of inflammation. In addition to their roles in metabolizing psychotropic drugs, substances of abuse, and endogenous compounds, brain CYPs impact drug efficacy, safety, and resistance, underscoring their importance beyond traditional drug metabolism. Their involvement in critical physiological processes also links them to neuroprotection, with significant implications for the onset and progression of neurodegenerative diseases. Understanding the roles of cerebral CYP enzymes is vital for advancing neuroprotective strategies, personalizing treatments for brain disorders, and developing CNS-targeting therapeutics. This review explores the emerging roles of CYP enzymes, particularly those within the CYP1-3 and CYP46 families, highlighting their functional diversity and the pathological consequences of their dysregulation on neurological health. It also examines the potential of cerebral CYP-based biomarkers to improve the diagnosis and treatment of neurodegenerative disorders, offering new avenues for therapeutic innovation.

MicroRNAs alteration and unique distribution in the soma and synapses of substantia nigra in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative condition after Alzheimer's. Abnormal accumulation of alpha-synuclein (α-syn) aggregates disrupts the balance of dopaminergic (DA-ergic) synapse components, interfering with dopamine transmission and leading to synaptic dysfunction and neuronal loss in PD. However exact molecular mechanism underlying DA-ergic neuronal cell loss in the SNpc in not known. MicroRNAs (miRNAs) are observed in various compartments of neural elements including cell bodies, nerve terminals, mitochondria, synaptic vesicles and synaptosomes. However, miRNAs expression and cellular distribution are unknown in the soma and synapse compartment in PD and healthy state. To address this void of information, we isolated synaptosomes and cytosolic fractions (soma) from post-mortem brains of PD-affected individuals and unaffected controls (UC) and processed for miRNA sequencing analysis. A group of miRNAs were significantly altered ( p < 0.05) with high fold changes (variance +/- > 2-fold) in their expressions in different comparisons: 1. UC synaptosome vs UC cytosol, 2. PD synaptosome vs PD cytosol, 3. PD synaptosome vs UC synaptosome, 4. PD cytosol vs UC cytosol. Our study unveiled some potential miRNAs in PD and their alteration and unique distribution in the soma and synapses of SNpc in PD and controls. Further, gene ontology enrichment analysis showed the involvement of deregulated miRNAs in several molecular function and cellular components: synapse assembly formation, cell junction organization, cell projections, mitochondria, Calcium ion binding and protein binding activities.

The association between Parkinson disease and Toxocara infection/exposure: A case-control study

Parkinson's disease (PD) is a prevalent neurological disorder and the second most common neurodegenerative disease. Research has explored the impact of infectious agents, such as the parasites, on neurological conditions, including PD. Given the limited studies worldwide and in Iran, this study aims to investigate the relationship between Toxocara infection and PD. This case-control study involved 91 PD patients and 90 healthy controls. After obtaining consent, serum samples and questionnaires were collected. All sera were examined using an ELISA test for IgG antibodies against Toxocara canis. Results were analyzed with SPSS, using chi-square tests, and odds ratios (OR), and confidence intervals (CI) were calculated via univariate and multivariate analyses. The prevalence of anti-Toxocara IgG was 33% (30/91) in PD patients and 33.3% (30/90) in the control group. Both univariate analysis (OR: 0.98; 95% CI: 0.52-1.82) and multivariate analysis (OR: 0.95; 95% CI: 0.49-1.83) indicated no statistically significant association. Additionally, univariate analysis (OR: 0.49; 95% CI: 0.16-1.5) and multivariate analysis (OR: 0.37; 95% CI: 0.09-1.43) suggested non-significant association between Toxocara infection and the severity of PD. Our findings do not support a statistically significant association between Toxocara infection and the PD. While the analysis suggested that Toxocara infection might reduce the severity of PD, these results were also not statistically significant. Further research with larger sample sizes and diverse populations is needed to fully understand the potential relationship between Toxocara infection and PD.

The centenarian blueprint: lessons in defying Parkinson's disease

Recent advancements in neurology have shifted focus from mere diagnosis to comprehensive management of movement disorders, particularly Parkinson's Disease (PD), which is rapidly increasing in prevalence due to global ageing trends. While age is a key risk factor for PD, centenarians often exhibit a remarkably low prevalence of the disease, presenting an intriguing paradox. This viewpoint explores potential reasons for this low prevalence, drawing on studies from regions with high centenarian populations, known as Blue Zones. The authors highlight the importance of genetic, lifestyle, and environmental factors in promoting healthy ageing and examines how these may contribute to the resilience against PD found in centenarians. By understanding the protective mechanisms in centenarians, particularly the concept of hormesis and factors like diet, exercise, and social connections, we may inform prevention strategies for PD. The study proposes the "EAT, MOVE, SLEEP, PROTECT, and REPEAT" approach as a framework for lifestyle interventions to counteract PD risk factors. Ultimately, centenarians offer valuable insights into delaying neurodegeneration, providing a model for potential preventive trials for PD.