Parkinson's Disease: Biomarkers, Treatment, and Risk Factors

Ethnopharmacological validation of Karkataka Taila-An edible crab Rasayana in rotenone-induced in vitro and in vivo models of Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE

'Karkataka Taila (KT), an ancient Ayurvedic Rasayana comprising the edible freshwater crab Scylla serrata Forskal flesh, is still used by local traditional practitioners in Kerala state to treat tremors and palsy. In the scientific community, it becomes less exposed due to the lack of adequate scientific validations and brief reports. There has been no published research on the effectiveness of KT in treating Parkinson's disease (PD).

PURPOSE

The purpose of the current research work was to investigate the anti-Parkison's potential of KT against rotenone-induced neurotoxicity in SH-SY5Y cell lines and rat model of PD and investigate underlying molecular mechanisms.

MATERIALS AND METHODS

The components of KT have been identified by gas chromatography-mass spectroscopy (GC-MS). The neuroprotective activity of KT was assessed using SH-SY5Y cell lines and rats against rotenone-induced PD. The parameters used for asses the neuroprotection are antioxidant markers (ROS and SOD), anti-inflammatory markers (IL-6, IL-1β, TNF-α, and nitrite), and dopamine levels. Behavioral evaluation and rat brain histopathology were carried out to further support the neuroprotection.

RESULT

Analysis using GC-MS revealed 36 constituents in KT. In vitro, the KT displayed considerable neuroprotective effects in terms of decreasing oxidative stress (ROS and SOD), neuroinflammation (IL-6, IL-1β, TNF-α, and nitrite), and elevating dopamine concentration. In vivo data showing improvements in histopathological and biochemical parameters confirmed the in vitro study findings, and in terms of behavioral assays, KT displayed significant activity.

CONCLUSION

GC-MS profiling was used to identify the bioactive compounds of KT with antioxidant, anti-inflammatory, and neuroprotective properties. As a result, they may be responsible for the therapeutic effects of KT on PD.

Application of metallic nanoparticles-amyloid protein supramolecular materials in tissue engineering and drug delivery: Recent progress and perspectives

Supramolecular medicine refers to the formulation of therapeutic and diagnostic agents through supramolecular techniques, amid treating, diagnosing, and preventing disease. Recently, there has been growing interest in developing metal nanoparticles (MNPs)-amyloid hybrid materials, which have the potential to revolutionize medical applications. Furthermore, the development of MNPs-amyloid hydrogel/scaffold supramolecules represents a promising new direction in amyloid nanotechnology, with potential applications in tissue engineering and biomedicine. This review first provides a brief introduction to the formation process of protein amyloid aggregates and their unique nanostructures. Subsequently, we focused on recent investigations into the use of MNPs-amyloid hybrid materials in tissue engineering and biomedicine. We anticipate that MNPs-amyloid supramolecular materials will pave the way for new functional materials in medical science, particularly in the field of tissue engineering.

Chronic pramipexole and rasagiline treatment enhances dendritic spine structural neuroplasticity in striatal and prefrontal cortex neurons of rats with bilateral intrastriatal 6-hydroxydopamine lesions

Parkinson's disease manifests as neurological alterations within dendritic spines in the striatal and neocortical brain regions, where their functionality closely correlates with morphology. However, the impact of current pharmacotherapy on dendritic spine neuroplasticity, crucial for novel drug development in neurological and psychiatric disorders, remains unclear. This study investigated the effects of 6-OHDA intrastriatal bilateral lesions in male adult rats on behavior and dendritic spine neuroplasticity in striatal and cortical neurons. Furthermore, it evaluated the influence of chronic co-administration of pramipexole (PPX), a D3 receptor agonist, and rasagiline (Ras), a selective MAO-B inhibitor, on these alterations. Lesioned animals exhibited impaired balance behavior, with no improvement following PPX-Ras treatment. The 6-OHDA lesion decreased dendritic spine density in caudate putamen (CPU) spiny projection neurons (SPNs), a change unaffected by treatment, though PPX-Ras increased mushroom spines and reduced stubby spines in these neurons. In nucleus accumbens (NAcc) SPNs and prefrontal cortex layer 3 (PFC-3) pyramidal cells, dendritic spine density remained unaltered, but PPX-Ras decreased mushroom spines and increased bifurcated spines in the NAcc, while increasing mushroom spines and decreasing stubby spines in PFC-3 in lesioned rats. These findings emphasize the importance of dendritic spines as promising targets for innovative pharmacotherapies for Parkinson's disease.

Unraveling Dysregulated Cell Signaling Pathways, Genetic and Epigenetic Mysteries of Parkinson's Disease

Parkinson's disease (PD) is a prevalent and burdensome neurodegenerative disorder that has been extensively researched to understand its complex etiology, diagnosis, and treatment. The interplay between genetic and environmental factors in PD makes its pathophysiology difficult to comprehend, emphasizing the need for further investigation into genetic and epigenetic markers involved in the disease. Early diagnosis is crucial for optimal management of the disease, and the development of novel diagnostic biomarkers is ongoing. Although many efforts have been made in the field of recognition and interpretation of the mechanisms involved in the pathophysiology of the disease, the current knowledge about PD is just the tip of the iceberg. By scrutinizing genetic and epigenetic patterns underlying PD, new avenues can be opened for dissecting the pathology of the disorder, leading to more precise and efficient diagnostic and therapeutic approaches. This review emphasizes the importance of studying dysregulated cell signaling pathways and molecular processes associated with genes and epigenetic alterations in understanding PD, paving the way for the development of novel therapeutic strategies to combat this devastating disease.

Angiotensin-(1-7) relieves behavioral defects and α-synuclein expression through NEAT1/miR-153-3p axis in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder, whose characteristic pathology involves progressive deficiency of dopaminergic neurons and generation of Lewy bodies (LBs). Aggregated and misfolded α-synuclein (α-syn) is the major constituent of LBs. As the newly discovered pathway of renin-angiotensin system (RAS), Angiotensin-(1-7) (Ang-(1-7)) and receptor Mas have attracted increasing attentions for their correlation with PD, but underlying mechanisms remain not fully clear. Based on above, this study established PD models of mice and primary dopaminergic neurons with AAV-hα-syn(A53T), then discussed the effects of Ang-(1-7)/Mas on α-syn level and neuronal apoptosis for these models combined with downstream long non-coding RNA (lncRNA) and microRNA (miRNA). Results showed that Ang-(1-7) alleviated behavioral impairments, rescued dopaminergic neurons loss and lowered α-syn expression in substantia nigra of hα-syn(A53T) overexpressed PD mice. We also discovered that Ang-(1-7) decreased level of α-syn and apoptosis in the hα-syn(A53T) overexpressed dopaminergic neurons through lncRNA NEAT1/miR-153-3p axis. Moreover, miR-153-3p level in peripheral blood is found negatively correlated with that of α-syn. In conclusion, our work not only showed neuroprotective effect and underlying mechanisms for Ang-(1-7) on α-syn in vivo and vitro, but also brought new hope on miR-153-3p and NEAT1 for diagnosis and treatment in PD.

Identification of high-affinity Monoamine oxidase B inhibitors for depression and Parkinson's disease treatment: bioinformatic approach of drug repurposing

Depression and Parkinson's disease (PD) are devastating psychiatric and neurological disorders that require the development of novel therapeutic interventions. Drug repurposing targeting predefined pharmacological targets is a widely use approach in modern drug discovery. Monoamine oxidase B (MAO-B) is a critical protein implicated in Depression and PD. In this study, we undertook a systematic exploration of repurposed drugs as potential inhibitors of MAO-B. Exploring a library of 3,648 commercially available drug molecules, we conducted virtual screening using a molecular docking approach to target the MAO-B binding pocket. Two promising drug molecules, Brexpiprazole and Trifluperidol, were identified based on their exceptional binding potential and drug profiling. Subsequently, all-atom molecular dynamics (MD) simulations were performed on the MAO-B-ligand complexes for a trajectory of 300 nanoseconds (ns). Simulation results demonstrated that the binding of Brexpiprazole and Trifluperidol induced only minor structural alterations in MAO-B and showed significant stabilization throughout the simulation trajectory. Overall, the finding suggests that Brexpiprazole and Trifluperidol exhibit strong potential as repurposed inhibitors of MAO-B that might be explored further in experimental investigations for the development of targeted therapies for depression and PD.

Multicolorimetric Sensor Array Based on Silver Metallization of Gold Nanorods for Discriminating Dopaminergic Agents

Dopaminergic agents are compounds that modulate dopamine-related activity in the brain and peripheral nerves within the pathways on both sides of the blood-brain barrier. Atypical levels of them can precipitate a multitude of neurological disorders, whose timely diagnosis signifies not only stopping the advancement of the illness but also surmounting it. A silver metallized gold nanorod (AuNRs) conditional sensor array, designed to detect dopaminergic agents for assessing nervous system disorders, yielded significant results in simultaneous detection and discrimination of Benserazide (Benz), Levodopa (L-DOPA), and Carbidopa (Carb). The array was composed of two different concentrations of silver ions as sensor elements (SEs), which generated unique signatures indicative of the presence of reductive target analytes, triggered by the incongruent formation of the Au@Ag core-shell, causing visual and fingerprint colorimetric patterns. Generating diverse responses is the key to the functionality of array-based sensing, which facilitated achieving spectral and color variation originating from the blue shift of AuNRs longitudinal localized surface plasmon resonance (LLSPR) in the extinction spectrum. Also, employing a smartphone camera enables clear visual discrimination across an extensive concentration span. Pattern recognition through linear discriminant analysis (LDA) underscored the robust discrimination accuracies of this sensor, along with quantification by means of partial least-squares regression (PLSR), affirming its potential for practical applications. Notably, the array demonstrated high sensitivity in detecting varied concentrations of target analytes, even in commercial drug samples. The sensor responses exhibited a linear correlation with the concentrations of Benz, L-DOPA, and Carb ranging from 1.59 to 100.0, 5.26 to 100.0, and 5.32 to 100.0 μmol L-1, respectively, and the minimum detectable concentrations for Benz, L-DOPA, and Carb were measured at 0.53, 1.75, and 1.77 μmol L-1, respectively. The implemented machine-learning-empowered array-based sensor represents advancements in dopaminergic agent tracing and naked eye detection.

The combination of 18F-fluorodeoxyglucose and 18F 9-fluoropropyl-(+)-dihydrotetrabenazine positron emission tomography for distinguishing between early-onset and late-onset idiopathic Parkinson disease and analyzing influencing factors

Background

The classification of Parkinson disease by age of onset has proven to be a valuable method for subtyping, given its practical application in clinical settings. However, the interactions between the metabolic brain changes, dopaminergic dysfunction, and clinical manifestations in patients with early-onset (early-iPD) and late-onset (late-iPD) idiopathic Parkinson disease have not been adequately evaluated. Therefore, this study aimed to investigate the difference in cerebral metabolism and presynaptic dopaminergic function between patients with early-iPD and those with late-onset disease using 18F-fluorodeoxyglucose (18F-FDG) and [18F] 9-fluoropropyl-(+)-dihydrotetrabenazine (18F-FP-DTBZ) positron emission tomography (PET). Furthermore, the goal was to further explore the correlation between imaging measurements and clinical manifestations in the early and late idiopathic patients with Parkinson disease.

Methods

This cross-sectional study included 80 patients with idiopathic Parkinson disease and 29 healthy control participants who underwent 18F-FDG and18F-FP-DTBZ PET imaging at Xuanwu Hospital, Capital Medical University from August 2022 to August 2023. The patients were categorized into early-iPD (n=27) and late-iPD (n=53) groups based on an age threshold of 50 years. The mean standardized uptake value of 18F-FDG and the standardized uptake value ratio (SUVR) of 18F-FP-DTBZ were compared between the early-iPD and late-iPD groups using unpaired Student t-tests. Furthermore, pairwise correlations among cerebral metabolism, dopaminergic function, and corresponding clinical ratings in all patients were conducted using Pearson correlation analysis.

Results

Patients with late-iPD exhibited a significant metabolic decrease in the frontal, parietal, and temporal cortex, along with the globus pallidus, putamen, thalamus, and cerebellum, compared to those with early-iPD in 18F-FDG PET imaging (all P values <0.05). Furthermore, the 18F-FP-DTBZ binding potential was significantly lower in the contralateral caudate and anterior putamen of patients with late-iPD compared to those with early-iPD (contralateral caudate: 3.16±1.2 vs. 2.63±0.7, P=0.020; contralateral anterior putamen: 2.49±1.2 vs. 2.05±0.7, P=0.040). Further analysis of the correlations between imaging clinical features revealed that glucose metabolism increases and dopaminergic function decreases with higher motor ratings.

Conclusions

18F-FDG and 18F-FP-DTBZ PET offer an objective molecular imaging basis for distinguishing between early-onset and late-onset idiopathic with Parkinson disease. Additionally, correlation analysis between imaging and clinical data represents a new approach for exploring the potential applications in future studies involving patients with early-iPD and late-iPD.

Immunity impacts cognitive deficits across neurological disorders

Cognitive deficits are a common comorbidity with neurological disorders and normal aging. Inflammation is associated with multiple diseases including classical neurodegenerative dementias such as Alzheimer's disease (AD) and autoimmune disorders such as multiple sclerosis (MS), in which over half of all patients experience some form of cognitive deficits. Other degenerative diseases of the central nervous system (CNS) including frontotemporal lobe dementia (FTLD), and Parkinson's disease (PD) as well as traumatic brain injury (TBI) and psychological disorders like major depressive disorder (MDD), and even normal aging all have cytokine-associated reductions in cognitive function. Thus, there is likely commonality between these secondary cognitive deficits and inflammation. Neurological disorders are increasingly associated with substantial neuroinflammation, in which CNS-resident cells secrete cytokines and chemokines such as tumor necrosis factor (TNF)α and interleukins (ILs) including IL-1β and IL-6. CNS-resident cells also respond to a wide variety of cytokines and chemokines, which can have both direct effects on neurons by changing the expression of ion channels and perturbing electrical properties, as well as indirect effects through glia-glia and immune-glia cross-talk. There is significant overlap in these cytokine and chemokine expression profiles across diseases, with TNFα and IL-6 strongly associated with cognitive deficits in multiple disorders. Here, we review the involvement of various cytokines and chemokines in AD, MS, FTLD, PD, TBI, MDD, and normal aging in the absence of dementia. We propose that the neuropsychiatric phenotypes observed in these disorders may be at least partially attributable to a dysregulation of immunity resulting in pathological cytokine and chemokine expression from both CNS-resident and non-resident cells.

Recent developments in intranasal drug delivery of nanomedicines for the treatment of neuropsychiatric disorders

Neuropsychiatric disorders are multifaceted syndromes with confounding neurological explanations. It includes anxiety, depression, autism spectrum disorder, attention deficit hyperactivity disorder, schizophrenia, Tourette's syndrome, delirium, dementia, vascular cognitive impairment, and apathy etc. Globally, these disorders occupy 15% of all diseases. As per the WHO, India has one of the largest populations of people with mental illnesses worldwide. The blood-brain barrier (BBB) makes it extremely difficult to distribute medicine to target cells in the brain tissues. However, it is possible through novel advancements in nanotechnology, molecular biology, and neurosciences. One such cutting-edge delivery method, nose-to-brain (N2B) drug delivery using nanoformulation (NF), overcomes traditional drug formulation and delivery limitations. Later offers more controlled drug release, better bioavailability, improved patient acceptance, reduced biological interference, and circumvention of BBB. When medicines are delivered via the intranasal (IN) route, they enter the nasal cavity and go to the brain via connections between the olfactory and trigeminal nerves and the nasal mucosa in N2B. Delivering phytochemical, bioactive and synthetic NF is being investigated with the N2B delivery strategy. The mucociliary clearance, enzyme degradation, and drug translocations by efflux mechanisms are significant issues associated with N2B delivery. This review article discusses the types of neuropsychiatric disorders and their treatment with plant-derived as well as synthetic drug-loaded NFs administered via the IN-delivery system. In conclusion, this review provided a comprehensive and critical overview of the IN applicability of plant-derived NFs for psychiatric disorders.

Ginsenoside Rg1 ameliorates stress-exacerbated Parkinson's disease in mice by eliminating RTP801 and α-synuclein autophagic degradation obstacle

Emerging evidence shows that psychological stress promotes the progression of Parkinson's disease (PD) and the onset of dyskinesia in non-PD individuals, highlighting a potential avenue for therapeutic intervention. We previously reported that chronic restraint-induced psychological stress precipitated the onset of parkinsonism in 10-month-old transgenic mice expressing mutant human α-synuclein (αSyn) (hαSyn A53T). We refer to these as chronic stress-genetic susceptibility (CSGS) PD model mice. In this study we investigated whether ginsenoside Rg1, a principal compound in ginseng notable for soothing the mind, could alleviate PD deterioration induced by psychological stress. Ten-month-old transgenic hαSyn A53T mice were subjected to 4 weeks' restraint stress to simulate chronic stress conditions that worsen PD, meanwhile the mice were treated with Rg1 (40 mg· kg-1 ·d-1, i.g.), and followed by functional magnetic resonance imaging (fMRI) and a variety of neurobehavioral tests. We showed that treatment with Rg1 significantly alleviated both motor and non-motor symptoms associated with PD. Functional MRI revealed that Rg1 treatment enhanced connectivity between brain regions implicated in PD, and in vivo multi-channel electrophysiological assay showed improvements in dyskinesia-related electrical activity. In addition, Rg1 treatment significantly attenuated the degeneration of dopaminergic neurons and reduced the pathological aggregation of αSyn in the striatum and SNc. We revealed that Rg1 treatment selectively reduced the level of the stress-sensitive protein RTP801 in SNc under chronic stress conditions, without impacting the acute stress response. HPLC-MS/MS analysis coupled with site-directed mutation showed that Rg1 promoted the ubiquitination and subsequent degradation of RTP801 at residues K188 and K218, a process mediated by the Parkin RING2 domain. Utilizing αSyn A53T+; RTP801-/- mice, we confirmed the critical role of RTP801 in stress-aggravated PD and its necessity for Rg1's protective effects. Moreover, Rg1 alleviated obstacles in αSyn autophagic degradation by ameliorating the RTP801-TXNIP-mediated deficiency of ATP13A2. Collectively, our results suggest that ginsenoside Rg1 holds promise as a therapeutic choice for treating PD-sensitive individuals who especially experience high levels of stress and self-imposed expectations.

Regulatory miR-SNP rs4636297A > G in miR-126 is linked to increased risk of rigidity feature in patients with Parkinson's disease

INTRODUCTION

A growing body of strong evidence shows that the dysfunction of miRNAs plays key roles in the development and progression of Parkinson's disease (PD), however, little data has been reported on the association of their SNPs with PD susceptibility. In this study, we investigated the association of regulatory miR-SNP rs4636297A > G with a functional effect on the expression of miRNA-126, as a key dysregulated miRNA in the PD, with the susceptibility and clinical features of the PD.

METHODS AND MATERIALS

In current study, we included a population consisting of 120 patients with PD and 120 clinically healthy individuals, and their blood samples were taken. After extracting the DNAs, the genotyping of the miR-SNP rs4636297A > G was done through RFLP-PCR technique. Finally, the association of this SNP with the risk and clinical features of PD was determined.

RESULTS

Although the results showed that the two groups did not differ significantly in terms of allelic and genotype frequencies, it was clinically found that individuals with genotypes carrying the minor allele G (AG and GG genotypes) of the miR-SNP rs4636297A > G had an increased risk of developing rigidity feature in the PD compared to its homozygous major AA genotype (GG genotype; OR = 5.14, p = 0.038 & GA genotype; OR = 4.32, p = 0.032).

CONCLUSION

We report for the first time a significant association of functional regulatory SNP rs4636297A > G in the miR-126 with the Parkinson's clinicopathology. Therefore, this miR-SNP can have a potential predictive biomarker capacity for rigidity in PD, although this hypothesis needs further investigation in the future.

Association between polygenic risk for schizophrenia and retinal morphology: A cross-sectional analysis of the United Kingdom Biobank

We examined the relationship between genetic risk for schizophrenia (SZ), using polygenic risk scores (PRSs), and retinal morphological alterations. Retinal structural and vascular indices derived from optical coherence tomography (OCT) and color fundus photography (CFP) and PRSs for SZ were analyzed in N = 35,024 individuals from the prospective cohort study, United Kingdom Biobank (UKB). Results indicated that macular ganglion cell-inner plexiform layer (mGC-IPL) thickness was significantly inversely related to PRS for SZ, and this relationship was strongest within higher PRS quintiles and independent of potential confounders and age. PRS, however, was unrelated to retinal vascular characteristics, with the exception of venular tortuosity, and other retinal structural indices (macular retinal nerve fiber layer [mRNFL], inner nuclear layer [INL], cup-to-disc ratio [CDR]). Additionally, the association between greater PRS and reduced mGC-IPL thickness was only significant for participants in the 40-49 and 50-59 age groups, not those in the 60-69 age group. These findings suggest that mGC-IPL thinning is associated with a genetic predisposition to SZ and may reflect neurodevelopmental and/or neurodegenerative processes inherent to SZ. Retinal microvasculature alterations, however, may be secondary consequences of SZ and do not appear to be associated with a genetic predisposition to SZ.

Circulating microRNAs as potential biomarkers for the diagnosis of Parkinson's disease: A meta-analysis

BACKGROUND AND OBJECTIVE

Parkinson's disease (PD) is the one of the most common neurodegenerative diseases. Many investigators have confirmed the possibility of using circulating miRNAs to diagnose PD. However, the results were inconsistent. Therefore, the aim of this meta-analysis was to systematically evaluate the diagnostic accuracy of circulating miRNAs in the diagnosis of PD.

METHODS

We carefully searched PubMed, Embase, Web of Science, Cochrane Library, Wanfang database and China National Knowledge Infrastructure for relevant studies (up to January 1, 2022) based on PRISMA statement. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), the diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated to test the diagnostic accuracy. Furthermore, subgroup analyses were performed to identify the potential sources of heterogeneity, and the Deeks' funnel plot asymmetry test was used to evaluate the potential publication bias.

RESULTS

Forty-four eligible studies from 16 articles (3298 PD patients and 2529 healthy controls) were included in the current meta-analysis. The pooled sensitivity was 0.79 (95% CI: 0.76-0.81), specificity was 0.82 (95% CI: 0.78-0.84), PLR was 4.3 (95% CI: 3.6-5.0), NLR was 0.26 (95% CI: 0.23-0.30), DOR was 16 (95% CI: 13-21), and AUC was 0.87 (95% CI: 0.84-0.90). Subgroup analysis suggested that miRNA cluster showed a better diagnostic accuracy than miRNA simple. Moreover, there was no significant publication bias.

CONCLUSIONS

Circulating miRNAs have great potential as novel non-invasive biomarkers for PD diagnosis.

Association of synuclein alpha (SNCA) gene polymorphisms with spontaneous brain activity in patients with Parkinson's disease

Background

The synuclein alpha (SNCA) gene responsible for encoding alpha-synuclein, is believed to play a crucial role in the pathogenesis of Parkinson's disease (PD). However, the specific impact of SNCA gene single-nucleotide polymorphisms (SNPs) on brain function in PD remains unclear. Therefore, this cross-sectional retrospective study, particularly through use of imaging analysis, aimed to characterize the relationship between SNCA gene SNPs and spontaneous brain activity in PD in order to enhance our understanding of the mechanisms underlying PD pathogenesis.

Methods

A total of 63 patients with PD and 73 sex- and age-matched healthy control (HC) participants were recruited from outpatient and inpatient clinics at Fujian Medical University Union Hospital from August 2017 to November 2019, and all underwent a resting-state functional magnetic resonance imaging (rs-fMRI) scanning. All participants were also examined to determine the correlation of different genotypes with regional brain activity measured by rs-fMRI using amplitude of low-frequency fluctuation (ALFF) analysis. Multivariate regression analysis was used to calculate the correlation between the brain function data and clinical features. All rs-fMRI data were analyzed with the SPM12 software and adjusted according to the false discovery rate (FDR) at the cluster level.

Results

This study included 63 patients with PD and 73 sex- and age-matched healthy participants were included in the study. The spontaneous brain activity in the right superior cerebellum (Cerebelum_Crus1_R), vermis (Vermis_7), and left supplementary motor area (Supp_Motor_Area_L) of patients in the PD group was weak compared to that in the HC group. The z-score ALFF of left central posterior gyrus was positively correlated with the Mini-Mental State Examination score (r=0.542; P<0.001) in the PD group. For rs11931074, the main genotypic effects were found in the left inferior cerebellum (Cerebellum_9_L) and right anterior cingulate and paracingulate gyri (Cingulum_Ant_R); for rs356219 and rs356165, the main genotypic effects were found in the left caudate nucleus (Caudate_L). An interaction effect of disease with genotype was found in the right inferior parietal gyrus (Parietal_Inf_R) only for rs356219.

Conclusions

Our study found a correlation of the SNCA SNPs rs11931074, rs356219, and rs356165 with brain functional alterations in patients with PD. Furthermore, an interaction effect was found in the right inferior parietal gyrus only for rs356219. This study may contribute to furthering the understanding of the influence of SNCA gene SNPs on brain function in patients with PD.

DNA tetrahedral nanocages as a promising nanocarrier for dopamine delivery in neurological disorders

Dopamine is a neurotransmitter in the central nervous system that is essential for many bodily and mental processes, and a lack of it can cause Parkinson's disease. DNA tetrahedral (TD) nanocages are promising in bio-nanotechnology, especially as a nanocarrier. TD is highly programmable, biocompatible, and capable of cell differentiation and proliferation. It also has tissue and blood-brain barrier permeability, making it a powerful tool that could overcome potential barriers in treating neurological disorders. In this study, we used DNA TD as a carrier for dopamine to cells and zebrafish embryos. We investigated the mechanism of complexation between TD and dopamine hydrochloride using gel electrophoresis, fluorescence and circular dichroism (CD) spectroscopy, atomic force microscopy (AFM), and molecular dynamic (MD) simulation tools. Further, we demonstrate that these dopamine-loaded DNA TD nanostructures enhanced cellular uptake and differentiation ability in SH-SY5Y neuroblastoma cells. Furthermore, we extended the study to zebrafish embryos as a model organism to examine survival and uptake. The research provides valuable insights into the complexation mechanism and cellular uptake of dopamine-loaded DNA tetrahedral nanostructures, paving the way for further advancements in nanomedicine for Parkinson's disease and other neurological disorders.

Mitochondrial stress-induced H4K12 hyperacetylation dysregulates transcription in Parkinson's disease

Aberrant epigenetic modification has been implicated in the pathogenesis of Parkinson's disease (PD), which is characterized by the irreversible loss of dopaminergic (DAergic) neurons. However, the mechanistic landscape of histone acetylation (ac) in PD has yet to be fully explored. Herein, we mapped the proteomic acetylation profiling changes at core histones H4 and thus identified H4K12ac as a key epigenomic mark in dopaminergic neuronal cells as well as in MitoPark animal model of PD. Notably, the significantly elevated H4K12ac deposition in post-mortem PD brains highlights its clinical relevance to human PD. Increased histone acetyltransferase (HAT) activity and decreased histone deacetylase 2 (HDAC2) and HDAC4 were found in experimental PD cell models, suggesting the HAT/HDAC imbalance associated with mitochondrial stress. Following our delineation of the proteasome dysfunction that possibly contributes to H4K12ac deposition, we characterized the altered transcriptional profile and disease-associated pathways in the MitoPark mouse model of PD. Our study uncovers the axis of mitochondrial impairment-H4K12ac deposition-altered transcription/disease pathways as a neuroepigenetic mechanism underlying PD pathogenesis. These findings provide mechanistic information for the development of potential pharmacoepigenomic translational strategies for PD.

Assessment of CRISPRa-mediated gdnf overexpression in an In vitro Parkinson's disease model

Introduction

Parkinson's disease (PD) presents a significant challenge in medical science, as current treatments are limited to symptom management and often carry significant side effects. Our study introduces an innovative approach to evaluate the effects of gdnf overexpression mediated by CRISPRa in an in vitro model of Parkinson's disease. The expression of gdnf can have neuroprotective effects, being related to the modulation of neuroinflammation and pathways associated with cell survival, differentiation, and growth.

Methods

We have developed a targeted delivery system using a magnetite nanostructured vehicle for the efficient transport of genetic material. This system has resulted in a substantial increase, up to 200-fold) in gdnf expression in an In vitro model of Parkinson's disease using a mixed primary culture of astrocytes, neurons, and microglia.

Results and Discussion

The delivery system exhibits significant endosomal escape of more than 56%, crucial for the effective delivery and activation of the genetic material within cells. The increased gdnf expression correlates with a notable reduction in MAO-B complex activity, reaching basal values of 14.8 μU/μg of protein, and a reduction in reactive oxygen species. Additionally, there is up to a 34.6% increase in cell viability in an In vitro Parkinson's disease model treated with the neurotoxin MPTP. Our study shows that increasing gdnf expression can remediate some of the cellular symptoms associated with Parkinson's disease in an in vitro model of the disease using a novel nanostructured delivery system.

Alzheimer's Disease Related Biomarkers Were Associated with Amnestic Cognitive Impairment in Parkinson's Disease: A Cross-Sectional Cohort Study

BACKGROUND

Cognitive impairment is common in patients with Parkinson's disease (PD) and occurs through multiple mechanisms, including Alzheimer's disease (AD) pathology and the involvement of α-synucleinopathies. We aimed to investigate the pathological biomarkers of both PD and AD in plasma and neuronal extracellular vesicles (EVs) and their association with different types of cognitive impairment in PD patients.

METHODS

A total of 122 patients with PD and 30 healthy controls were included in this cross-sectional cohort study between March 2021 and July 2023. Non-dementia PD patients were divided into amnestic and non-amnestic groups according to the memory domain of a neuropsychological assessment. Plasma and neuronal EV biomarkers, including α-synuclein (α-syn), beta-amyloid (Aβ), total tau (T-tau), phosphorylated tau181 (p-tau181), and glial fibrillary acidic protein (GFAP), were measured using a single-molecule array and a chemiluminescence immunoassay, respectively.

RESULTS

Neuronal EV but not plasma α-syn levels, were significantly increased in PD as compared to healthy controls, and they were positively associated with UPDRS part III scores and the severity of cognitive impairment. A lower plasma Aβ42 level and higher neuronal EV T-tau level were found in the amnestic PD group compared to the non-amnestic PD group.

CONCLUSIONS

The results of the current study demonstrate that neuronal EV α-syn levels can be a sensitive biomarker for assisting in the diagnosis and disease severity prediction of PD. Both AD and PD pathologies are important factors in cognitive impairment associated with PD, and AD pathologies are more involved in amnestic memory deficit in PD.

Artificial intelligence in Parkinson's disease: Early detection and diagnostic advancements

Parkinson's disease (PD) is the second most common neurodegenerative disorder, globally affecting men and women at an exponentially growing rate, with currently no cure. Disease progression starts when dopaminergic neurons begin to die. In PD, the loss of neurotransmitter, dopamine is responsible for the overall communication of neural cells throughout the body. Clinical symptoms of PD are slowness of movement, involuntary muscular contractions, speech & writing changes, lessened automatic movement, and chronic tremors in the body. PD occurs in both familial and sporadic forms and modifiable and non-modifiable risk factors and socioeconomic conditions cause PD. Early detectable diagnostics and treatments have been developed in the last several decades. However, we still do not have precise early detectable biomarkers and therapeutic agents/drugs that prevent and/or delay the disease process. Recently, artificial intelligence (AI) science and machine learning tools have been promising in identifying early detectable markers with a greater rate of accuracy compared to past forms of treatment and diagnostic processes. Artificial intelligence refers to the intelligence exhibited by machines or software, distinct from the intelligence observed in humans that is based on neural networks in a form and can be used to diagnose the longevity and disease severity of disease. The term Machine Learning or Neural Networks is a blanket term used to identify an emerging technology that is created to work in the way of a "human brain" using many intertwined neurons to achieve the same level of raw intelligence as that of a brain. These processes have been used for neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, to assess the severity of the patient's condition. In the current article, we discuss the prevalence and incidence of PD, and currently available diagnostic biomarkers and therapeutic strategies. We also highlighted currently available artificial intelligence science and machine learning tools and their applications to detect disease and develop therapeutic interventions.

Protein modification in neurodegenerative diseases

Posttranslational modifications play a crucial role in governing cellular functions and protein behavior. Researchers have implicated dysregulated posttranslational modifications in protein misfolding, which results in cytotoxicity, particularly in neurodegenerative diseases such as Alzheimer disease, Parkinson disease, and Huntington disease. These aberrant posttranslational modifications cause proteins to gather in certain parts of the brain that are linked to the development of the diseases. This leads to neuronal dysfunction and the start of neurodegenerative disease symptoms. Cognitive decline and neurological impairments commonly manifest in neurodegenerative disease patients, underscoring the urgency of comprehending the posttranslational modifications' impact on protein function for targeted therapeutic interventions. This review elucidates the critical link between neurodegenerative diseases and specific posttranslational modifications, focusing on Tau, APP, α-synuclein, Huntingtin protein, Parkin, DJ-1, and Drp1. By delineating the prominent aberrant posttranslational modifications within Alzheimer disease, Parkinson disease, and Huntington disease, the review underscores the significance of understanding the interplay among these modifications. Emphasizing 10 key abnormal posttranslational modifications, this study aims to provide a comprehensive framework for investigating neurodegenerative diseases holistically. The insights presented herein shed light on potential therapeutic avenues aimed at modulating posttranslational modifications to mitigate protein aggregation and retard neurodegenerative disease progression.

Alpha Synuclein Toxicity and Non-Motor Parkinson's

Parkinson's disease (PD) is a common multisystem neurodegenerative disorder affecting 1% of the population over the age of 60 years. The main neuropathological features of PD are the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the presence of alpha synuclein (αSyn)-rich Lewy bodies both manifesting with classical motor signs. αSyn has emerged as a key protein in PD pathology as it can spread through synaptic networks to reach several anatomical regions of the body contributing to the appearance of non-motor symptoms (NMS) considered prevalent among individuals prior to PD diagnosis and persisting throughout the patient's life. NMS mainly includes loss of taste and smell, constipation, psychiatric disorders, dementia, impaired rapid eye movement (REM) sleep, urogenital dysfunction, and cardiovascular impairment. This review summarizes the more recent findings on the impact of αSyn deposits on several prodromal NMS and emphasizes the importance of early detection of αSyn toxic species in biofluids and peripheral biopsies as prospective biomarkers in PD.

Embryonic Zebrafish as a Model for Investigating the Interaction between Environmental Pollutants and Neurodegenerative Disorders

Environmental pollutants have been linked to neurotoxicity and are proposed to contribute to neurodegenerative disorders. The zebrafish model provides a high-throughput platform for large-scale chemical screening and toxicity assessment and is widely accepted as an important animal model for the investigation of neurodegenerative disorders. Although recent studies explore the roles of environmental pollutants in neurodegenerative disorders in zebrafish models, current knowledge of the mechanisms of environmentally induced neurodegenerative disorders is relatively complex and overlapping. This review primarily discusses utilizing embryonic zebrafish as the model to investigate environmental pollutants-related neurodegenerative disease. We also review current applicable approaches and important biomarkers to unravel the underlying mechanism of environmentally related neurodegenerative disorders. We found embryonic zebrafish to be a powerful tool that provides a platform for evaluating neurotoxicity triggered by environmentally relevant concentrations of neurotoxic compounds. Additionally, using variable approaches to assess neurotoxicity in the embryonic zebrafish allows researchers to have insights into the complex interaction between environmental pollutants and neurodegenerative disorders and, ultimately, an understanding of the underlying mechanisms related to environmental toxicants.

Emerging perspectives on precision therapy for Parkinson's disease: multidimensional evidence leading to a new breakthrough in personalized medicine

PD is a prevalent and progressive neurodegenerative disorder characterized by both motor and non-motor symptoms. Genes play a significant role in the onset and progression of the disease. While the complexity and pleiotropy of gene expression networks have posed challenges for gene-targeted therapies, numerous pathways of gene variant expression show promise as therapeutic targets in preclinical studies, with some already in clinical trials. With the recognition of the numerous genes and complex pathways that can influence PD, it may be possible to take a novel approach to choose a treatment for the condition. This approach would be based on the symptoms, genomics, and underlying mechanisms of the disease. We discuss the utilization of emerging genetic and pathological knowledge of PD patients to categorize the disease into subgroups. Our long-term objective is to generate new insights for the therapeutic approach to the disease, aiming to delay and treat it more effectively, and ultimately reduce the burden on individuals and society.

Bidirectional two-sample Mendelian randomization analysis identifies causal associations between oxidative stress and Parkinson's disease

Background

Observational studies have shown that oxidative stress (OS) is associated with Parkinson's disease (PD). However, whether such observations reflect cause-effect remains largely unknown. To test this, we performed a two-sample bidirectional Mendelian randomization (MR) analysis to investigate the causal-effects between OS biomarkers and PD.

Methods

We selected summary statistics data for single-nucleotide polymorphisms (SNPs) associated with catalase (n = 13), glutathione peroxidases (n = 12), superoxide dismutase (n = 13), vitamin A (n = 7), vitamin C (n = 10), vitamin E (n = 12), vitamin B12 (n = 8), folate (n = 14), copper (n = 6), Zinc (n = 7), and iron (n = 23) levels, and the corresponding data for PD from the International Parkinson Disease Genomics Consortium (IPDGC, 33,674 cases and 449,056 controls). Inverse-variance weighted (IVW) MR analyses were conducted to estimate associations of OS with PD. Reverse MR analysis was further performed to predict the causal effects of PD on the above OS biomarkers.

Results

As for PD, the IVW method suggested that the Zinc (Zn) levels was significantly associated with PD (OR = 1.107, 95% CI 1.013-1.211; p = 0.025), which is consistent with results from the weighted median analyses. Moreover, the results remained consistent and robust in the sensitivity analysis. However, there were no significant associations of catalase, glutathione peroxidases, superoxide dismutase, vitamin A, vitamin C, vitamin E, vitamin B12, folate, copper, or iron with PD. As for OS, our reverse MR analysis also did not support a causal effect of liability to PD on OS.

Conclusion

The MR study supported the causal effect of Zn on PD. These findings may inform prevention strategies and interventions directed toward OS and PD.

Preclinical evaluation of [18F]FP-CIT, the radiotracer targeting dopamine transporter for diagnosing Parkinson's disease: pharmacokinetic and efficacy analysis

BACKGROUND

N-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane (FP-CIT), the representative cocaine derivative used in dopamine transporter imaging, is a promising biomarker, as it reflects the severity of Parkinson's disease (PD). 123I- and 18F-labeled FP-CIT has been used for PD diagnosis. However, preclinical studies evaluating [18F]FP-CIT as a potential diagnostic biomarker are scarce. Among translational research advancements from bench to bedside, translating preclinical findings into clinical practice is one-directional. The aim of this study is to employ a circular approach, beginning back from the preclinical stage, progressing to the supplementation of [18F]FP-CIT, and subsequently returning to clinical application. We investigated the pharmacokinetic properties of [18F]FP-CIT and its efficacy for PD diagnosis using murine models.

RESULTS

Biodistribution, metabolite and excretion analyses were performed in mice and PD models were induced in rats using 6-hydroxydopamine (6-OHDA). The targeting efficiency of [18F]FP-CIT for the dopamine receptor was assessed through animal PET/CT imaging. Subsequently, correlation analysis was conducted between animal PET/CT imaging results and immunohistochemistry (IHC) targeting tyrosine hydroxylase. Rapid circulation was confirmed after [18F]FP-CIT injection. [18F]FP-CIT reached the highest uptake of 23.50 ± 12.46%ID/g in the striatum 1 min after injection, and it was rapidly excreted within 60 min. The major metabolic organs of [18F]FP-CIT were confirmed to be the intestines, liver, and kidneys. Its uptake in the intestine was approximately 5% ID/g. The uptake in the liver gradually increased, with excretion beginning after reaching a maximum after 60 min. The kidneys exhibited rapid elimination after 10 min. In the excretion study, rapid elimination was verified, with 21.46 ± 9.53% of the compound excreted within a 6 h period. Additionally, the efficacy of [18F]FP-CIT PET was demonstrated in the PD model, with a high correlation with IHC for both the absolute value (R = 0.803, p = 0.0017) and the ratio value (R = 0.973, p = 0.0011).

CONCLUSIONS

This study fills the gap regarding insufficient preclinical studies on [18F]FP-CIT, including its ADME, metabolites, and efficiency. The pharmacological results, including accurate diagnosis, rapid circulation, and [18F]FP-CIT excretion, provide complementary evidence that [18F]FP-CIT can be used safely and efficiently to diagnose PD in clinics, although it is already used in clinics.

Coffee and Parkinson's disease

Parkinson's disease (PD) is a prevalent neurodegenerative disease marked by dopaminergic neuronal loss and misfolded alpha-synuclein (α-syn) accumulation, which results in both motor and cognitive symptoms. Its occurrence grows with age, with a larger prevalence among males. Despite substantial study, effective medicines to reduce or stop the progression of diseases remain elusive. Interest has grown in examining dietary components, such as caffeine present in coffee, for potential medicinal effects. Epidemiological studies imply a lower incidence of PD with coffee drinking, attributable to caffeine's neuroprotective abilities. Beyond caffeine, coffee constituent like chlorogenic acid and cafestol have anti-Parkinsonian benefits. Moreover, coffee use has been related with variations in gut microbiota composition, which may reduce intestinal inflammation and prevent protein misfolding in enteric nerves, perhaps through the microbiota-gut-brain axis. This review gives a summary of the neuroprotective effects of coffee, investigating both its motor and non-motor advantages in individuals with PD as well as in experimental models of PD. We reviewed some bioactive constituents of coffee, their respective interactions with misfolded α-syn accumulation, and its emerging mechanisms associated to the gut microbiome.

Exploring the Potential Therapeutic Approach Using Ginsenosides for the Management of Neurodegenerative Disorders

There is a need for an efficient and long-lasting treatment due to the population's increasing prevalence of neurodegenerative disorders. In an effort to generate fresh ideas and create novel therapeutic medications, scientists have recently started to investigate the biological functions of compounds derived from plants and herbs. Ginseng, famous Chinese herbal medicine, has therapeutic value by virtue of its compounds ginsenosides or panaxosides, which are triterpene saponins and steroid glycosides. Research revealed positive impacts on ameliorating various disease conditions and found it as a possible drug candidate. Several neuroprotection mechanisms followed by this compound are inhibition of cell apoptosis, oxidative stress, inflammatory, and tumor activity. It has been demonstrated that controlling these mechanisms enhances cognitive performance and safeguards the brain against neurodegenerative disorders. The main objective of this review is to give a description of the most recent studies on ginsenoside's possible therapeutic application in the treatment of neurodegenerative diseases. Using organic compounds like ginseng and its various components may create new avenues for innovative treatment approaches development for neurological diseases. However, further research is necessary to confirm the stability and effectiveness of ginsenosides for neurodegenerative disease.

Association Study Between Kynurenine 3-Monooxygenase (KMO) Gene and Parkinson's Disease Patients

The influence of various risk factors such as aging, intricate cellular molecular processes, and lifestyle factors like smoking, alcohol consumption, caffeine intake, and occupational factors has received increased focus in relation to the risk and development of Parkinson's disease (PD). Limited research has been conducted on the assessment of lifestyle impact on kynurenine 3-monooxygenase (KMO) gene in PD. A total of 164 subjects, including 82 PD cases and 82 healthy individuals, were recruited based on specific inclusion and exclusion criteria. The severity of PD and clinical assessment were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr (HY) scaling. Sanger sequencing was performed to analyse the KMO gene in the recruited subjects, and case-control studies were conducted. The UPDRS assessment revealed significant impairments in smell, tremors, walking, and posture instability in the late-onset PD cohorts. The HY scaling indicated a higher proportion of late-onset cohorts in stage 2. Moreover, both alcoholic and non-alcoholic groups showed significantly increased levels of 3-HK in late-onset PD. Gene analysis identified missense variants at position g.241593373 T > A (rs752312199) and intronic variants at positions g.241592623A > G (rs640718), g.241592800C > A (rs990388262), g.241592802A > C (rs1350160268), g.241592808 T > C (rs1478255936), and g.241592812G > T (rs948928931). The alterations in the KMO gene were found to influence the levels of kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK). Genomic analysis revealed a high prevalence of missense mutations in the late-onset PD groups, leading to a decline in 3-HK levels in patients. This leads to the reduction of the progression of disease in late-onset groups which shows that this mutation may lead to the protective effect on the PD subjects. This study suggests the use of KYNA and 3-HK as potential biomarkers in analysing the progression of disease. This study is limited by its small sample size. To overcome this limitation, a larger study involving in greater number of participants is needed to thoroughly investigate the KMO gene and KP metabolites, to enhance our understanding of Parkinson's disease progression, and to enhance diagnostic capabilities.

Identification of metabolites reproducibly associated with Parkinson's Disease via meta-analysis and computational modelling

Many studies have reported metabolomic analysis of different bio-specimens from Parkinson's disease (PD) patients. However, inconsistencies in reported metabolite concentration changes make it difficult to draw conclusions as to the role of metabolism in the occurrence or development of Parkinson's disease. We reviewed the literature on metabolomic analysis of PD patients. From 74 studies that passed quality control metrics, 928 metabolites were identified with significant changes in PD patients, but only 190 were replicated with the same changes in more than one study. Of these metabolites, 60 exclusively increased, such as 3-methoxytyrosine and glycine, 54 exclusively decreased, such as pantothenic acid and caffeine, and 76 inconsistently changed in concentration in PD versus control subjects, such as ornithine and tyrosine. A genome-scale metabolic model of PD and corresponding metabolic map linking most of the replicated metabolites enabled a better understanding of the dysfunctional pathways of PD and the prediction of additional potential metabolic markers from pathways with consistent metabolite changes to target in future studies.

Transdermal delivery of resveratrol loaded solid lipid nanoparticle as a microneedle patch: a novel approach for the treatment of Parkinson's disease

Parkinson's disease (PD), affecting millions of people worldwide and expected to impact 10 million by 2030, manifests a spectrum of motor and non-motor symptoms linked to the decline of dopaminergic neurons. Current therapies manage PD symptoms but lack efficacy in slowing disease progression, emphasizing the urgency for more effective treatments. Resveratrol (RSV), recognized for its neuroprotective and antioxidative properties, encounters challenges in clinical use for PD due to limited bioavailability. Researchers have investigated lipid-based nanoformulations, specifically solid lipid nanoparticles (SLNs), to enhance RSV stability. Oral drug delivery via SLNs faces obstacles, prompting exploration into transdermal delivery using SLNs integrated with microneedles (MNs) for improved patient compliance. In this study, an RSV-loaded SLNs (RSV -SLNs) incorporated into the MN patch was developed for transdermal RSV delivery to improve its stability and patient compliance. Characterization studies demonstrated favorable physical properties of SLNs with a sustained drug release profile of 78.36 ± 0.74%. The developed MNs exhibited mechanical robustness and skin penetration capabilities. Ex vivo permeation studies displayed substantial drug permeation of 68.39 ± 1.4% through the skin. In an in vivo pharmacokinetic study, the RSV-SLNs delivered through MNs exhibited a significant increase in Cmax, Tmax, and AUC0 - t values, alongside a reduced elimination rate in blood plasma in contrast to the administration of pure RSV via MNs. Moreover, an in vivo study showcased enhanced behavioral functioning and increased brain antioxidant levels in the treated animals. In-vivo skin irritation study revealed no signs of irritation till 24 h which permits long-term MNs application. Histopathological analysis showed notable changes in the brain regions of the rat, specifically the striatum and substantia nigra, after the completion of the treatment. Based on these findings, the development of an RSV-SLN loaded MNs (RSVSNLMP) patch presents a novel approach, with the potential to enhance the drug's efficiency, patient compliance, and therapeutic outcomes for PD, offering a promising avenue for advanced PD therapy.

Investigating the role of rotenone on human blood platelets: Molecular insights into abnormal platelet functions in Parkinson's disease

Parkinson's disease (PD) is a predominant neuromotor disorder characterized by the selective death of dopaminergic neurons in the midbrain. The majority of PD cases are sporadic or idiopathic, with environmental toxins and pollutants potentially contributing to its development or exacerbation. However, clinical PD patients are often associated with a reduced stroke frequency, where circulating blood platelets are indispensable. Although platelet structural impairment is evident in PD, the platelet functional alterations and their underlying molecular mechanisms are still obscure. Therefore, we investigated rotenone (ROT), an environmental neurotoxin that selectively destroys dopaminergic neurons mimicking PD, on human blood platelets to explore its impact on platelet functions, thus replicating PD conditions in vitro. Our study deciphered that ROT decreased thrombin-induced platelet functions, including adhesion, activation, secretion, and aggregation in human blood platelets. As ROT is primarily responsible for generating intracellular reactive oxygen species (ROS), and ROS is a key player regulating the platelet functional parameters, we went on to check the effect of ROT on platelet ROS production. In our investigation, it became evident that ROT treatment resulted in the stimulation of ROS production in human blood platelets. Additionally, we discovered that ROT induced ROS production by augmenting Ca2+ mobilization from inositol 1,4,5-trisphosphate receptor. Apart from this, the treatment of ROT triggers protein kinase C associated NADPH oxidase-mediated ROS production in platelets. In summary, this research, for the first time, highlights ROT-induced abnormal platelet functions and may provide a mechanistic insight into the altered platelet activities observed in PD patients.

Neuro-modulatory impact of felodipine against experimentally-induced Parkinson's disease: Possible contribution of PINK1-Parkin mitophagy pathway

Parkinson's disease (PD) is a prevalent neurodegenerative disorder, characterized by motor and psychological dysfunction. Palliative treatment and dopamine replenishment therapy are the only available therapeutic options. Calcium channel blockers (CCBs) have been reported to protect against several neurodegenerative disorders. The current study was designed to evaluate the neuroprotective impact of Felodipine (10 mg/kg, orally) as a CCB on motor and biochemical dysfunction associated with experimentally induced PD using rotenone (2.5 mg/kg, IP) and to investigate the underlying mechanisms. Rotenone induced deleterious neuromotor outcomes, typical of those associated with PD. The striatum revealed increased oxidative burden and NO levels with decreased antioxidant capacity. Nrf2 content significantly decreased with the accumulation of α-synuclein and tau proteins in both the substantia nigra and striatum. These observations significantly improved with felodipine treatment. Of note, felodipine increased dopamine levels in the substantia nigra and striatum as confirmed by the suppression of inflammation and the significant reduction in striatal NF-κB and TNF-α contents. Moreover, felodipine enhanced mitophagy, as confirmed by a significant increase in mitochondrial Parkin and suppression of LC3a/b and SQSTM1/p62. In conclusion, felodipine restored dopamine synthesis, attenuated oxidative stress, inflammation, and mitochondrial dysfunction, and improved the mitophagy process resulting in improved PD-associated motor impairment.

Recent updates on structural insights of MAO-B inhibitors: a review on target-based approach

Parkinson's disease is a neurodegenerative disorder characterized by slow movement, tremors, and stiffness caused due to loss of dopaminergic neurons caused in the brain's substantia nigra. The concentration of dopamine is decreased in the brain. Parkinson's disease may be happened because of various genetic and environmental factors. Parkinson's disease is related to the irregular expression of the monoamine oxidase (MAO) enzyme, precisely type B, which causes the oxidative deamination of biogenic amines such as dopamine. MAO-B inhibitors, available currently in the market, carry various adverse effects such as dizziness, nausea, vomiting, lightheadedness, fainting, etc. So, there is an urgent need to develop new MAO-B inhibitors with minimum side effects. In this review, we have included recently studied compounds (2018 onwards). Agrawal et al. reported MAO-B inhibitors with IC50 0.0051 µM and showed good binding affinity. Enriquez et al. reported a compound with IC50 144 nM and bind with some critical amino acid residue Tyr60, Ile198, and Ile199. This article also describes the structure-activity relationship of the compounds and clinical trial studies of related derivatives. These compounds may be used as lead compounds to develop potent compounds as MAO-B inhibitors.

Orexin B protects dopaminergic neurons from 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity associated with reduced extracellular signal-regulated kinase phosphorylation

BACKGROUND

The loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) is a major pathological hallmark of Parkinson's disease (PD). Orexin B (OXB) has been reported to promote the growth of DA neurons. However, the roles of OXB in the degeneration of DA neurons still remained not fully clear.

METHODS

An in vivo PD model was constructed by administrating 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice. Pole test was performed to investigate the motor function of mice and the number of DA neurons was detected by immunofluorescence (IF). A PD cell model was established by treating SH-SY5Y cells with 1-methyl-4-phenylpyridinium (MPP+). OXB was added to the culture medium 2 h after MPP + treatment. Microscopic analysis was carried out to investigate the function of OXB in the cell model of PD 24 h after MPP + challenge. RNA-Seq analysis of the PD cell model was performed to explore the possible mechanisms. Western blot was used to detect the phosphorylation levels of extracellular signal-regulated kinase (ERK).

RESULTS

OXB significantly decreased the DA neurons death caused by MPTP, alleviated MPP+-induced neurotoxicity in SH-SY5Y cells, and robustly enhanced the weight and motor ability of PD mice. Besides, RNA-Seq analysis demonstrated that the mitogen-activated protein kinase (MAPK) pathway was involved in the pathology of PD. Furthermore, MPP + led to increased levels of phosphorylation of ERK (p-ERK), OXB treatment significantly decreased the levels of p-ERK in MPP+-treated SH-SY5Y cells.

CONCLUSIONS

This study demonstrated that OXB exerts a neuroprotective role associated with reduced ERK phosphorylation in the PD model. This suggests that OXB may have therapeutic potential for treatment of PD.

The causal effects of intelligence and fluid intelligence on Parkinson's disease: a Mendelian randomization study

Background

Parkinson's disease (PD) is a chronic neurodegenerative disease that affects the central nervous system, primarily the motor nervous system, and occurs most often in older adults. A large number of studies have shown that high intelligence leads to an increased risk of PD. However, whether there is a causal relationship between intelligence on PD has not yet been reported.

Methods

In this study, Mendelian randomization (MR) analysis was performed with intelligence (ebi-a-GCST006250) and fluid intelligence score (ukb-b-5238) as exposure factors and PD (ieu-b-7) as an outcome, which the datasets were mined from the IEU OpenGWAS database. MR analysis was performed through 3 methods [MR Egger, weighted median, inverse variance weighted (IVW)], of which IVW was the primary method. In addition, the reliability of the results of the MR analysis was assessed via the heterogeneity test, the horizontal polytropy test, and Leave-One-Out (LOO). Finally, based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, the genes corresponding to intelligence and fluid intelligence score related to SNPs were enriched for functional features and pathways.

Results

The results of MR analysis suggested that elevated intelligence indicators can increase the risk of PD [p = 0.015, Odd Ratio (OR) = 1.316]. Meanwhile, fluid intelligence score was causally associated with the PD (p = 0.035), which was a risk factor (OR = 1.142). The reliability of the results of MR analysis was demonstrated by sensitivity analysis. Finally, the results of GO enrichment analysis for 87 genes corresponding to intelligence related SNPs mainly included regulation of synapse organization, developmental cell growth, etc. These genes were enriched in the synaptic vessel cycle, polycomb expressive complex in KEGG. Similarly, 44 genes corresponding to SNPs associated with fluid intelligence score were used for enrichment analysis. Based on the GO database, these genes were mainly enriched in regulation of developmental growth, negative regulation of neuron projection development, etc. In KEGG, 44 genes corresponding to SNPs associated with fluid intelligence score were enriched in signaling pathways including Alzheimer's disease, the cellular senescence, etc.

Conclusion

The causal relationships between intelligence and fluid intelligence scores, and PD were demonstrated through MR analysis, providing an important reference and evidence for the study of PD.

Correlation between dietary factors and Parkinson's disease revealed by the analysis of Mendelian randomization

Background

The intricate interplay between dietary habits and the development of Parkinson's Disease (PD) has long been a subject of scientific inquiry. Mendelian Randomization (MR) emerges as a potent tool, harnessing genetic variants to infer causality in observational data. While evidence links diet to Parkinson's Disease (PD) etiology, a thorough MR exploration of dietary impacts on PD, particularly involving gut microbiota, is still emerging.

Methods

This research leverages the IEU Open GWAS project's vast GWAS database to address the knowledge gap in understanding diet's influence on PD, employing a diverse range of dietary variables. Our holistic dataset includes various foods like processed fava beans, bap, red wine, to cheese, reflecting a commitment to untangling dietary complexities in PD etiology. Advancing from initial dietary-PD associations, we innovatively explore the gut microbiota, focusing on Parabacteroides goldsteinii, in relation to bap intake and PD, employing MR. Utilizing weighted median, MR-Egger, and inverse variance weighting methods, we ensure rigorous causality assessments, meticulously mitigating pleiotropy and heterogeneity biases to uphold finding validity.

Results

Our findings indicate red wine (OR: 1.031; 95% CI 1.001-1.062; p = 0.044) and dried fruit consumption (OR: 2.019; 95% CI 1.052-3.875; p = 0.035) correlate with increased PD risk, whereas broad beans (OR: 0.967; 95% CI 0.939-0.996; p = 0.024) and bap intake (OR: 0.922; 95% CI 0.860-0.989; p = 0.023) show protective effects against PD. Employing MR, specifically the IVW method, revealed a significant inverse association between bap intake and gut microbiota, marked by an 8.010-fold decrease in Parabacteroides goldsteinii per standard deviation increase in bap intake (95% CI 1.005-63.818, p = 0.049). Furthermore, a connection between PD and Parabacteroides goldsteinii was observed (OR: 0.810; 95% CI 0.768-0.999; p = 0.049), suggesting a potential microbiota-mediated pathway in PD etiology.

Conclusion

Our study links dietary habits to PD risk, showing higher PD risk with red wine and dried fruit consumption, and a protective effect from broad beans and bap. Using MR, we found bap intake inversely correlates with Parabacteroides goldsteinii in the gut, suggesting bap influences microbiota. Further, higher Parabacteroides goldsteinii levels correlate with lower PD risk, highlighting a complex interplay of diet, gut microbiome, and neurological health. These insights shed light on potential dietary interventions for PD.

Dual-Task vs. Single-Task Gait Training to Improve Spatiotemporal Gait Parameters in People with Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

People with Parkinson's disease (pwPD) present alterations of spatiotemporal gait parameters that impact walking ability. While preliminary studies suggested that dual-task gait training improves spatiotemporal gait parameters, it remains unclear whether dual-task gait training specifically improves dual-task gait performance compared to single-task gait training. The aim of this review is to assess the effect of dual-task training relative to single-task gait training on specific gait parameters during dual-task tests in pwPD.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), searching three electronic databases. Two reviewers independently selected RCTs, extracted data, and applied the Cochrane risk-of-bias tool for randomized trials (Version 2) and the GRADE framework for assessing the certainty of evidence. The primary outcomes were dual-task gait speed, stride length, and cadence. Secondary outcomes included dual-task costs on gait speed, balance confidence, and quality of life.

RESULTS

We included 14 RCTs (548 patients). Meta-analyses showed effects favoring dual-task training over single-task training in improving dual-task gait speed (standardized mean difference [SMD] = 0.48, 95% confidence interval [CI] = 0.20-0.77; 11 studies; low certainty evidence), stride length (mean difference [MD] = 0.09 m, 95% CI = 0.04-0.14; 4 studies; very low certainty evidence), and cadence (MD = 5.45 steps/min, 95% CI = 3.59-7.31; 5 studies; very low certainty evidence). We also found a significant effect of dual-task training over single-task training on dual-task cost and quality of life, but not on balance confidence.

CONCLUSIONS

Our findings support the use of dual-task training relative to single-task training to improve dual-task spatiotemporal gait parameters in pwPD. Further studies are encouraged to better define the features of dual-task training and the clinical characteristics of pwPD to identify better responders.

MicroRNAs in microglia: deciphering their role in neurodegenerative diseases

This review presents a comprehensive analysis of the role of microRNAs in microglia and their implications in the pathogenesis of neurodegenerative diseases. Microglia, as the resident immune cells of the central nervous system (CNS), are pivotal in maintaining neural homeostasis and responding to pathological changes. Recent studies have highlighted the significance of miRNAs, small non-coding RNA molecules, in regulating microglial functions. In neurodegenerative diseases, such as Alzheimer's Disease (AD), Parkinson's Disease (PD), Amyotrophic Lateral Sclerosis (ALS), and Multiple Sclerosis (MS), dysregulated miRNA expression in microglia contributes to disease progression through various mechanisms such regulation of gene expression, as modulation of cytokine response and phagocytosis. This review synthesizes current knowledge on how miRNAs influence microglial activation, cytokine production, and phagocytic activity. Specific miRNAs, such as miR-155, are explored for their roles in modulating microglial responses in the context of neuroinflammation and neurodegeneration. The study also discusses the impact of miRNA dysregulation on the transition of microglia from a neuroprotective to a neurotoxic phenotype, a critical aspect in the progression of neurodegenerative diseases.

Tau- and α-synuclein-targeted gold nanoparticles: applications, opportunities, and future outlooks in the diagnosis and therapy of neurodegenerative diseases

The use of nanomaterials in medicine offers multiple opportunities to address neurodegenerative disorders such as Alzheimer's and Parkinson's disease. These diseases are a significant burden for society and the health system, affecting millions of people worldwide without sensitive and selective diagnostic methodologies or effective treatments to stop their progression. In this sense, the use of gold nanoparticles is a promising tool due to their unique properties at the nanometric level. They can be functionalized with specific molecules to selectively target pathological proteins such as Tau and α-synuclein for Alzheimer's and Parkinson's disease, respectively. Additionally, these proteins are used as diagnostic biomarkers, wherein gold nanoparticles play a key role in enhancing their signal, even at the low concentrations present in biological samples such as blood or cerebrospinal fluid, thus enabling an early and accurate diagnosis. On the other hand, gold nanoparticles act as drug delivery platforms, bringing therapeutic agents directly into the brain, improving treatment efficiency and precision, and reducing side effects in healthy tissues. However, despite the exciting potential of gold nanoparticles, it is crucial to address the challenges and issues associated with their use in the medical field before they can be widely applied in clinical settings. It is critical to ensure the safety and biocompatibility of these nanomaterials in the context of the central nervous system. Therefore, rigorous preclinical and clinical studies are needed to assess the efficacy and feasibility of these strategies in patients. Since there is scarce and sometimes contradictory literature about their use in this context, the main aim of this review is to discuss and analyze the current state-of-the-art of gold nanoparticles in relation to delivery, diagnosis, and therapy for Alzheimer's and Parkinson's disease, as well as recent research about their use in preclinical, clinical, and emerging research areas.

Integrative analysis of plasma and substantia nigra in Parkinson's disease: unraveling biomarkers and insights from the lncRNA-miRNA-mRNA ceRNA network

Introduction

Parkinson's disease (PD) is a rapidly growing neurological disorder characterized by diverse movement symptoms. However, the underlying causes have not been clearly identified, and accurate diagnosis is challenging. This study aimed to identify potential biomarkers suitable for PD diagnosis and present an integrative perspective on the disease.

Methods

We screened the GSE7621, GSE8397-GPL96, GSE8397-GPL97, GSE20163, and GSE20164 datasets in the NCBI GEO database to identify differentially expressed (DE) mRNAs in the substantia nigra (SN). We also screened the GSE160299 dataset from the NCBI GEO database to identify DE lncRNAs and miRNAs in plasma. We then constructed 2 lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) regulatory networks based on the ceRNA hypothesis. To understand the biological function, we performed Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analyses for each ceRNA network. The receiver operating characteristic analyses (ROC) was used to assess ceRNA results.

Results

We identified 7 upregulated and 29 downregulated mRNAs as common DE mRNAs in the 5 SN datasets. In the blood dataset, we identified 31 DE miRNAs (9 upregulated and 22 downregulated) and 332 DE lncRNAs (69 upregulated and 263 downregulated). Based on the determined interactions, 5 genes (P2RX7, HSPA1, SLCO4A1, RAD52, and SIRT4) appeared to be upregulated as a result of 10 lncRNAs sponging 4 miRNAs (miR-411, miR-1193, miR-301b, and miR-514a-2/3). Competing with 9 genes (ANK1, CBLN1, RGS4, SLC6A3, SYNGR3, VSNL1, DDC, KCNJ6, and SV2C) for miR-671, a total of 26 lncRNAs seemed to function as ceRNAs, influencing genes to be downregulated.

Discussion

In this study, we successfully constructed 2 novel ceRNA regulatory networks in patients with PD, including 36 lncRNAs, 5 miRNAs, and 14 mRNAs. Our results suggest that these plasma lncRNAs are involved in the pathogenesis of PD by sponging miRNAs and regulating gene expression in the SN of the brain. We propose that the upregulated and downregulated lncRNA-mediated ceRNA networks represent mechanisms of neuroinflammation and dopamine neurotransmission, respectively. Our ceRNA network, which was associated with PD, suggests the potential use of DE miRNAs and lncRNAs as body fluid diagnostic biomarkers. These findings provide an integrated view of the mechanisms underlying gene regulation and interactions in PD.

Cell-Penetrating Peptides: Promising Therapeutics and Drug-Delivery Systems for Neurodegenerative Diseases

Currently, one of the most significant and rapidly growing unmet medical challenges is the treatment of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). This challenge encompasses the imperative development of efficacious therapeutic agents and overcoming the intricacies of the blood-brain barrier for successful drug delivery. Here we focus on the delivery aspect with particular emphasis on cell-penetrating peptides (CPPs), widely used in basic and translational research as they enhance drug delivery to challenging targets such as tissue and cellular compartments and thus increase therapeutic efficacy. The combination of CPPs with nanomaterials such as nanoparticles (NPs) improves the performance, accuracy, and stability of drug delivery and enables higher drug loads. Our review presents and discusses research that utilizes CPPs, either alone or in conjugation with NPs, to mitigate the pathogenic effects of neurodegenerative diseases with particular reference to AD and PD.

Aptasensor-encapsulating semi-permeable proteinosomes for direct target detection in non-treated biofluids

Detecting biomarkers in biofluids directly without sample treatments makes molecular diagnostics faster and more efficient. Aptasensors, the nucleic acid-based molecular biosensors, can detect a wide range of target molecules, but their susceptibility to degradation and aggregation by nucleases and charged proteins, respectively, limits their direct use in clinical samples. In this work, we demonstrate that when aptasensors are encapsulated in proteinosomes, the protein-based liposome mimics, clinically important small molecules can be sensitively and selectively detected in non-treated specimens, such as 100 % unpurified serum. As serum albumin is used to form the membrane, the nanomeshed proteinosomes become semi-permeable and antifouling, which enables exclusive admission of small molecules while blocking unwanted large proteins. Consequently, the enclosed aptasensors can maintain close-to-optimal performance for target binding, and nucleolytic degradation and electrostatic aggregation are effectively suppressed. Three different structure-switching aptamers specific for estradiol, dopamine, and cocaine, respectively, are demonstrated to fully conserve their high affinities and specificities inside the microcapsules. The shielding effect of proteinosomes is indeed exceptional; the enclosed DNA aptasensors remain completely intact over 18 h in serum and even in an extremely concentrated DNase solution (1 mg/ml, ∼300,000× the serum level). Moreover, the proteinosome-mediated compartmentalization enables independent operation of multiple aptasensors in the same mixture. Hence, simultaneous real-time sensing of two different targets is demonstrated with different operation modes, 'recording' target appearance and 'reporting' target concentration changes. This work is the first demonstration of small-molecule-specific aptasensors operating with optimal performance in serum environments and will find promising applications in molecular diagnostics.

Development and internal validation of a prognostic model for loss of balance and falls in mid- to late-stage Parkinson's disease

BACKGROUND

Mid- to late-stage Parkinson's disease (PD) is often linked with worsened and significant impairment of motor activities, but existing prognostic markers do not adequately capture the risk of loss of balance in PD patients. This study aims to develop a risk prognostic model for mid- to late-stage PD and identify prognostic factors that are indicative of impending loss of balance and falls.

METHODS

The study included 307 participants of which 75 were diagnosed with idiopathic PD and 232 were neurological or non-neurological controls. Among the PD group, 46 were early-stage (Hoehn and Yahr [H&Y] = 1,2) with no significant loss of balance while 29 were mid- to late-stage (H&Y = 3,4,5) which is characterized by loss of balance and falls. Multivariable logistic regression (MLR) was used to develop a prognostic model for mid- to late-stage PD. Model discrimination was assessed by ROC curves. The model was internally validated through bootstrapping and calibration plots.

RESULTS

The relevant factors identified and included in the final MLR model were shortness of breath, age, swollen joints, heme oxygenase-1 (HO-1) protein, and total salivary protein. The model had an AUC of 0.82 (95% CI = 0.71-0.92) and was well calibrated (calibration slope = 0.77, intercept = 0.03). The likelihood of shortness of breath (OR = 7.91, 95% CI = 1.63-45.12) was significantly higher among mid- to late-stage PD than early-stage. Age and total salivary protein were also significantly higher among mid- to late-stage PD.

CONCLUSION

The MLR prognostic model for mid- to late-stage PD may assist physicians in identifying patients at high risk for loss of balance and falls.

Key Non-coding Variants in Three Neuroapoptosis and Neuroinflammation-Related LncRNAs Are Protectively Associated with Susceptibility to Parkinson's Disease and Some of Its Clinical Features

Research findings show that genetic susceptibility to sporadic Parkinson's disease (PD), a common neurodegenerative disorder, is determined through gene variation of loci involved in its development and pathogenesis. A growing body of strong evidence has revealed that dysfunction of long non-coding RNAs (lncRNAs) plays key roles in the pathogenesis and progression of PD through impairing neuronal signaling pathways, but little is known about the relationship between their variants and PD susceptibility. In this research, we intended to study the relationship between functional SNPs rs12826786C>T, rs3200401C>T, and rs6931097G>A in the key lncRNAs stimulating neuroapoptosis and neuroinflammation in PD, including HOTAIR, MALAT1, and lincRNA-P21, respectively, with susceptibility to PD as well as its clinical symptoms.The population of this study consisted of 240 individuals, including 120 controls and 120 cases, and the sample taken from them was peripheral blood. Genotyping of the target SNPs was done using PCR-RFLP. We found that the healthy individuals carry more T allele of MALAT1-rs3200401C>T compared to the patients (P= 0.019). Furthermore, it was observed that in the dominant genetic model, subjects with genotypes carrying the T allele have a lower risk of PD (OR= 0.530; CI= 0.296-0.950; P= 0.033). Regarding the lincRNA-P21-rs6931097G>A, we observed a significant protective relationship between its GA (OR= 0.144; CI= 0.030-0.680; P= 0.014) and AA (OR= 0.195; CI= 00.047-0.799; P= 0.023) genotypes with the manifestation of tremor and bradykinesia symptoms, respectively. Furthermore, the findings indicated that the minor TT genotype of HOTAIR-rs12826786C>T was significantly associated with a reduced risk of bradykinesia symptoms (OR= 0.147; CI= 0.039-0.555; P= 0.005). Collectively, these findings suggest that MALAT1-rs3200401C>T may be an important lncRNA SNP against the development of PD, while the other two SNPs show protective effects on the clinical manifestations of PD in a way that lincRNA-P21-rs6931097G>A has a protective effect against the occurrence of tremor and bradykinesia symptoms in PD patients, and HOTAIR -rs12826786C>T indicates a protective effect against the display of bradykinesia feature. Therefore, they can have valuable potential as biomarkers for clinical evaluations of this disease.

Oxidative Stress and Neurodegeneration: Insights and Therapeutic Strategies for Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative condition marked by the gradual deterioration of dopaminergic neurons in the substantia nigra. Oxidative stress has been identified as a key player in the development of PD in recent studies. In the first part, we discuss the sources of oxidative stress in PD, including mitochondrial dysfunction, dopamine metabolism, and neuroinflammation. This paper delves into the possibility of mitigating oxidative stress as a potential treatment approach for PD. In addition, we examine the hurdles and potential of antioxidant therapy, including the challenge of delivering antioxidants to the brain and the requirement for biomarkers to track oxidative stress in PD patients. However, even if antioxidant therapy holds promise, further investigation is needed to determine its efficacy and safety in PD treatment.

Rotenone-induced PINK1/Parkin-mediated mitophagy: establishing a silkworm model for Parkinson's disease potential

Parkinson's disease (PD), ranking as the second most prevalent neurodegenerative disorder globally, presents a pressing need for innovative animal models to deepen our understanding of its pathophysiology and explore potential therapeutic interventions. The development of such animal models plays a pivotal role in unraveling the complexities of PD and investigating promising treatment avenues. In this study, we employed transcriptome sequencing on BmN cells treated with 1 μg/ml rotenone, aiming to elucidate the underlying toxicological mechanisms. The investigation brought to light a significant reduction in mitochondrial membrane potential induced by rotenone, subsequently triggering mitophagy. Notably, the PTEN induced putative kinase 1 (PINK1)/Parkin pathway emerged as a key player in the cascade leading to rotenone-induced mitophagy. Furthermore, our exploration extended to silkworms exposed to 50 μg/ml rotenone, revealing distinctive motor dysfunction as well as inhibition of Tyrosine hydroxylase (TH) gene expression. These observed effects not only contribute valuable insights into the impact and intricate mechanisms of rotenone exposure on mitophagy but also provide robust scientific evidence supporting the utilization of rotenone in establishing a PD model in the silkworm. This comprehensive investigation not only enriches our understanding of the toxicological pathways triggered by rotenone but also highlights the potential of silkworms as a valuable model organism for PD research.

Gangliosides as Therapeutic Targets for Neurodegenerative Diseases

Gangliosides, sialic acid-containing glycosphingolipids, are abundant in cell membranes and primarily involved in controlling cell signaling and cell communication. The altered ganglioside pattern has been demonstrated in several neurodegenerative diseases, characterized during early-onset or infancy, emphasizing the significance of gangliosides in the brain. Enzymes required for the biosynthesis of gangliosides are linked to several devastating neurological disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), hereditary spastic paraplegia (HSP). In this review, we summarized not only the critical roles of biosynthetic enzymes and their inhibitors in ganglioside metabolism but also the efficacy of treatment strategies of ganglioside to address their significance in those diseases.

Insights from the neural guidance factor Netrin-1 into neurodegeneration and other diseases

Netrin-1 was initially discovered as a neuronal growth cue for axonal guidance, and its functions have later been identified in inflammation, tumorigenesis, neurodegeneration, and other disorders. We have recently found its alterations in the brains with Alzheimer's disease, which might provide important clues to the mechanisms of some unique pathologies. To provide better understanding of this promising molecule, we here summarize research progresses in genetics, pathology, biochemistry, cell biology and other studies of Netrin-1 about its mechanistic roles and biomarker potentials with an emphasis on clinical neurodegenerative disorders in order to expand understanding of this promising molecular player in human diseases.

Immunomodulatory activities and biomedical applications of melittin and its recent advances

Melittin (MLT), a peptide containing 26 amino acids, is a key constituent of bee venom. It comprises ∼40%-60% of the venom's dry weight and is the main pricing index for bee venom, being the causative factor of pain. The unique properties of MLT extracted from bee venom have made it a very valuable active ingredient in the pharmaceutical industry as this cationic and amphipathic peptide has propitious effects on human health in diverse biological processes. It has the ability to strongly impact the membranes of cells and display hemolytic activity with anticancer characteristics. However, the clinical application of MLT has been limited by its severe hemolytic activity, which poses a challenge for therapeutic use. By employing more efficient mechanisms, such as modifying the MLT sequence, genetic engineering, and nano-delivery systems, it is anticipated that the limitations posed by MLT can be overcome, thereby enabling its wider application in therapeutic contexts. This review has outlined recent advancements in MLT's nano-delivery systems and genetically engineered cells expressing MLT and provided an overview of where the MLTMLT's platforms are and where they will go in the future with the challenges ahead. The focus is on exploring how these approaches can overcome the limitations associated with MLT's hemolytic activity and improve its selectivity and efficacy in targeting cancer cells. These advancements hold promise for the creation of innovative and enhanced therapeutic approaches based on MLT for the treatment of cancer.