Oral pathogens exacerbate Parkinson's disease by promoting Th1 cell infiltration in mice

Gut microbiota in epilepsy: How antibiotics induce dysbiosis and influence seizure susceptibility

Epilepsy, a widespread chronic neurological disorder, has recently come under scrutiny for its potential association with the intricate dynamics of gut microbiota. Numerous investigations into the microbiota-gut-brain axis have revealed a close relationship between gut microbiota and epilepsy, suggesting gut microbiota as a potential treatment strategy. In clinical practice, a longstanding correlation has been observed between some kinds of antibiotics and the potential to induce seizures. Consequently, we have conceived a hypothesis that antibiotics might impact seizure activity by modulating the gut microbiota and influencing the physiological processes within the microbiota-gut-brain axis. In this review, our primary objective is to present the existing evidence and theoretical foundations supporting the hypothesis that dysbiosis within the gut microbiota may play a significant role in the pathophysiology of epilepsy. Furthermore, we aim to summarize the possible mechanisms between microbiota-gut-brain axis and epilepsy, offering insights into the selection of appropriate antibiotics for long-term epilepsy management and enhancing therapeutic efficacy through modulation of the gut microbiota. Further research is necessary to fully elucidate the intricate relationship between gut microbiota ecosystem and epilepsy. Exploring these connections holds promise for advancing our understanding of epilepsy pathogenesis and improving patient treatment and care.

Association between oral dysbiosis and Parkinson's disease: a systematic review

The oral cavity serves as the gateway to the human organism, hosting a diverse community of microorganisms that coexist in a state of symbiosis. Disruption of this balance leads to oral dysbiosis, a condition associated with infections and oral pathologies, which may contribute to the etiopathogenesis of systemic disorders such as Parkinson's disease, a neurodegenerative movement disorder characterized by resting tremor, rigidity, and bradykinesia. While oral dysbiosis is recognized as a risk factor and an aggravating element for Parkinson's disease, it is not regarded as a direct cause. This systematic review aims to synthesize existing research exploring the potential relationship between oral dysbiosis and the development of Parkinson's disease. Following a comprehensive analysis, 12 studies were selected, comprising 11 case-control studies and one observational analytical study. These studies investigated the composition of oral microbiota in different sample groups, revealing a higher abundance of pathogenic oral bacteria in individuals diagnosed with Parkinson's disease. The findings suggest that oral dysbiosis may influence both the onset of Parkinson's disease and the progression of symptoms such as cognitive decline. These results pave the way for future research, particularly regarding alterations in oral microbiota as potential biomarkers for early diagnosis and disease monitoring.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024540056.

HGF Aggravated Periodontitis-Associated Gut Barrier and Microbial Dysfunction: Implications for Oral-Gut Axis Regulation

While periodontitis is increasingly linked to systemic disorders through the oral-gut axis, the molecular mediators driving gut microbiota dysbiosis and barrier disruption remain elusive. Hepatocyte growth factor (HGF), a novel regulator of inflammatory bone loss in periodontitis, may serve as a critical communicator between oral infection and distal intestinal pathology. This study investigates how HGF overexpression modulates the gut microbial ecosystem and intestinal barrier integrity in a transgenic periodontitis model. In this study, we combined 16S rRNA sequencing of fecal microbiota with comprehensive gut barrier assessments, including systemic markers (D-lactate, LPS, and DAO ELISA), structural integrity (villous morphology), and molecular analysis (ZO-1, occludin, and NOD2 immunohistochemistry), using HGF-overexpressing transgenic (HGF-Tg) mice with periodontitis. The results demonstrated that HGF increased gut permeability in the context of periodontitis, as evidenced by elevated serum levels of D-lactate and LPS compared to wild type (WT) mice. In addition, gut villous morphology disorder was observed in HGF-Tg mice with periodontitis. HGF also diminished the protein level of occludin and upregulated NOD2 expression in mice with periodontitis. Moreover, HGF-Tg mice with periodontitis exhibited significant dysbiosis of gut microbiota, with reduced levels of probiotics (e.g., Faecalibaculum). Notably, HGF also increased the enrichment of the periodontitis-associated pathogens (e.g., Desulfovibrio and Streptococcus) in the gut. Microbial functions, particularly metabolic pathways, were significantly altered by HGF when periodontitis occurred. Some microorganisms like g_Desulfovibrio may play a role in gut barrier disorder in HGF-Tg mice with periodontitis. Overall, our findings position HGF as a novel orchestrator of oral-gut crosstalk, where its overexpression reshapes gut microbial ecology toward a "leaky gut" phenotype to compromise intestinal barrier integrity, further deepening our understanding of the oral-gut axis.

Sleep deprivation accelerates Parkinson's disease via modulating gut microbiota associated microglial activation and oxidative stress

The interplay between Parkinson's disease (PD) and sleep disturbances suggests that sleep problems constitute a risk factor for PD progression, but the underlying mechanisms remain unclear. Microglial activation and oxidative stress are considered to play an important role in the pathogenesis of aging and neurodegenerative diseases. We hypothesized that sleep deprivation (SD) could exacerbate PD progression via modulating microglial activation and oxidative stress. To test this hypothesis, we established a PD mouse model using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), then subjected the mice to SD. A battery of behavioral tests, including rotarod, pole, adhesive removal, and open field tests, were used to assess motor function. Our study showed that SD exacerbated motor deficits, loss of tyrosine hydroxylase (TH), microglial activation and oxidative stress damage in PD model mice. Fecal microbiota transplantation experiments revealed that SD mediated PD progression, microglial activation and oxidative stress via the gut microbiota. 16S rRNA sequencing analysis indicated that SD increased the abundances of bacteria such as Bacteroidaceae, while decreasing the abundances of bacteria including Lactobacillus. Non-targeted metabolomic analysis of gut microbiota-derived metabolites revealed that SD significantly increased the production of adenosine (ADO), a purine metabolite. Probiotic supplementation reversed the effects of SD on motor deficits, dopaminergic neuron loss, microglial activation and oxidative stress damage in PD mice; it also decreased SD-induced ADO production. Administration of Adenosine A2A receptor (A2AR) inhibitors, Istradefylline (Ist), attenuated the roles of SD and ADO in promoting microglial activation, oxidative stress and PD progression. Taken together, our findings indicate that SD accelerates PD progression via regulating microbiota associated microglial activation and oxidative stress, suggesting that efforts to improve sleep quality can be used to prevent and treat PD.

Uncovering potential molecular markers and pathological mechanisms of Parkinson's disease and myocardial infarction based on bioinformatics analysis

BACKGROUND

The direct association between Parkinson's disease (PD) and Myocardial infarction (MI) has been the subject of relatively limited research.

OBJECTIVE

The purpose of this study was to identify the genes most associated with PD and MI to explore their common pathogenesis.

METHODS

The gene expression profiles of PD and MI were downloaded from GEO database. Differential expression analysis was performed to identify the common differential expression genes (DEGs) of PD and MI, followed by functional annotation. Subsequently, protein-protein interaction network were constructed, and hub DEGs were identified based on CytoHubba plugin and LASSO regression analysis. To explore the potential molecular mechanism of hub DEGs, GSEA analysis, immune correlation analysis, drug prediction and molecular docking were performed, and transcription factors (TF) and lncRNA-miRNA-mRNA (ceRNA) regulatory networks were constructed.

RESULTS

A total of 48 DEGs with the same expression trend were identified in the MI vs. normal control (NC) and PD vs. NC groups. Functional annotation results showed that the common DEGs were significantly enriched in immune and inflammation-related pathways. RPS4Y1 and UTY were the most relevant hub DEGs for PD and MI, and may be involved in the HALLMARK_MYC_TARGETS_V1 and HALLMARK_PROTEIN_SECRETION pathways. TP63 was a common TF of RPS4Y1 and UTY. The PVT1/KCNQ1OT1-hsa-miR-31-5p-RPS4Y1 and KCNQ1OT1-hsa-let-7a-5p/hsa-miR-19b-3p-UTY axes may play an important role in regulating PD and MI. CYCLOHEXIMIDE and ATALAREN may be potential drugs for the treatment of PD and MI comorbidity. In addition, PD and MI exhibit different patterns of immune cell infiltration and immune function status, which may be related to the specific pathological processes of the disease.

CONCLUSIONS

This study revealed for the first time that RPS4Y1 and UTY may be common biomarkers of PD and MI and may be potential therapeutic targets. This study provides new perspective on the common molecular mechanisms between PD and MI.

Gut Microbiota-Induced Modulation of the Central Nervous System Function in Parkinson's Disease Through the Gut-Brain Axis and Short-Chain Fatty Acids

Recent insights into Parkinson's disease (PD), a progressive neurodegenerative disorder, suggest a significant influence of the gut microbiome on its pathogenesis and progression through the gut-brain axis. This study integrates 16S rRNA sequencing, high-throughput transcriptomic sequencing, and animal model experiments to explore the molecular mechanisms underpinning the role of gut-brain axis in PD, with a focus on short-chain fatty acids (SCFAs) mediated by the SCFA receptors FFAR2 and FFAR3. Our findings highlighted prominent differences in the gut microbiota composition between PD patients and healthy individuals, particularly in taxa such as Escherichia_Shigella and Bacteroidetes, which potentially impact SCFA levels through secondary metabolite biosynthesis. Notably, fecal microbiota transplantation (FMT) from healthy to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse models significantly improved motor function, enhanced dopamine and serotonin levels in the striatum, and increased the number of dopaminergic neurons in the substantia nigra while reducing glial cell activation. This therapeutic effect was associated with increased levels of SCFAs such as acetate, propionate, and butyrate in the gut of MPTP-lesioned mice. Moreover, transcriptomic analyses revealed upregulated expression of FFAR2 and FFAR3 in MPTP-lesioned mice, indicating their crucial role in mediating the benefits of FMT on the central nervous system. These results provide compelling evidence that gut microbiota and SCFAs play a critical role in modulating the gut-brain axis, offering new insights into PD's etiology and potential targets for therapeutic intervention.

The microbiota-gut-brain axis: a potential target in the small-molecule compounds and gene therapeutic strategies for Parkinson's disease

BACKGROUNDS

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by motor symptoms and non-motor symptoms. It has been found that intestinal issues usually precede motor symptoms. Microorganisms in the gastrointestinal tract can affect central nervous system through the microbiota-gut-brain axis. Accumulating evidence has shown that disturbances in the microbiota-gut-brain axis are linked with PD. Thus, this pathway appears to be a promising therapeutic target for treatment of PD.

OBJECTIVES

In this review, we mainly described gut dysbiosis in PD and their underlying mechanisms for mediating neuroinflammation and peripheral immune response in PD pathology and futher discussed the potential small-molecule compounds and genic therapeutic strategies targeting the microbiota-gut-brain axis and their applications in PD.

CONCLUSIONS

Studies have found that some small molecule compounds and alterations of inflammation-related genes can improve the motor and non-motor symptoms of PD by improving the microbiota-gut-brain axis, which may provide potentially beneficial drugs and molecular targets for the therapies of PD.

Prevalence of Epstein-Barr Virus, Cytomegalovirus, and Periodontopathic Bacteria in Patients With Periodontitis: A Case-Control Study

OBJECTIVES

Opportunistic viruses such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV) have been detected in gingival crevicular fluid (GCF) and saliva of patients with periodontal disease. However, the relationship between herpesviruses and periodontitis remains obscure. The aim of this case-control study was the detection and association of CMV and EBV with periodontitis.

MATERIAL AND METHODS

Forty-eight adults were included in this study: 24 patients with periodontitis (CP) and 24 periodontally healthy individuals (HS). All patients underwent periodontal examination, including probing depth (PD), clinical attachment loss (CAL), plaque index (PI), and bleeding on probing (BOP). Subgingival biofilm samples were collected from all patients and real-time PCR was performed for viral and bacterial detection. The odds ratio (OR) was calculated, and the chi-squared test or Fisher's exact test was performed to analyze the significant differences.

RESULTS

EBV was detected only in one healthy patient meanwhile no CMV was found. No statistically significant differences were found between the periodontal clinical parameters of EBV-positive patients and the negative ones: PI (p = 0.090), PD (p = 0.857), CAL (p = 0.801), and BOP (p = 0.104). Except for Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Prevotella intermedia (Pi), and Treponema denticola (Td) showed a statistically significant association (p < 0.001) with the clinical periodontal parameters. Aa presence was not statistically associated with periodontal sites (p < 0.296). Tf and Pg were the most frequently detected periodontopathic bacteria in the CP group (91.7% sites).

CONCLUSION

The present case-control study showed that the prevalence of EBV and CMV did not show significant differences between the groups evaluated in the Spanish population.

Deciphering the role of heat shock protein HSPA1L: biomarker discovery and prognostic insights in Parkinson's disease and glioma

BACKGROUND

Heat shock proteins (HSPs) play a critical role in cellular stress responses and have been implicated in numerous diseases, including Parkinson's disease (PD) and various cancers. Understanding the differential expression and functional implications of HSPs in these conditions is crucial for identifying potential therapeutic targets and biomarkers for diagnosis and prognosis.

METHODS

We utilized combined datasets (GSE6613 and GSE72267) to identify and analyze the heat shock-related genes differentially expressed in PD. Gene Set Variation Analysis (GSVA) was performed to explore functional profiles, while LASSO regression was employed to screen potential PD biomarkers. In glioma, prognostic value, immune infiltration, and pathway enrichment associated with HSPA1L gene expression were assessed via Kaplan-Meier plots, ssGSEA, and enrichment analyses.

RESULTS

In PD, we identified 17 differentially expressed HSPs. Enrichment analysis revealed significant pathways related to protein homeostasis and cellular stress responses. LASSO regression pinpointed 12 genes, including HSPA1L, as significant markers for PD, with nomogram and calibration plots indicating predictive accuracy. Stratification based on HSPA1L expression in PD highlighted differentially active biological processes, immune responses, and metabolic disruptions. In the pan-cancer analysis, HSPA1L showed variable expression across cancer types and a significant correlation with patient survival and immune infiltration. In glioma, low HSPA1L expression was associated with worse overall survival, distinct immune infiltration patterns, and altered pathway activities.

CONCLUSION

This integrative study reveals the substantial role of HSPs, especially HSPA1L, in the pathogenesis and prognosis of PD and glioma. Our findings offer new perspectives on the molecular mechanisms underlying these diseases and propose HSPA1L as a potential prognostic biomarker and a target for therapeutic intervention.

Microbiota Orchestra in Parkinson's Disease: The Nasal and Oral Maestros

Parkinson's disease (PD) is characterized by the progressive degeneration of dopaminergic neurons, leading to a range of motor and non-motor symptoms.

BACKGROUND/OBJECTIVES

Over the past decade, studies have identified a potential link between the microbiome and PD pathophysiology. The literature suggests that specific bacterial communities from the gut, oral, and nasal microbiota may be involved in neuroinflammatory processes, which are hallmarks of PD. This review aims to comprehensively analyze the current research on the composition, diversity, and dysbiosis characteristics of the nasal and oral microbiota in PD.

METHODS

Through a comprehensive search across scientific databases, we identify twenty original studies investigating the nasal and oral microbiota in PD.

RESULTS

Most of these studies demonstrate the substantial roles of bacterial communities in neuroinflammatory pathways associated with PD progression. They also underscore the influences of microbiota-derived factors on key aspects of PD pathology, including alpha-synuclein aggregation and immune dysregulation.

CONCLUSIONS

Finally, we discuss the potential diagnostic and therapeutic implications of modulating the nasal and oral microbiota in PD management. This analysis seeks to identify potential avenues for future research in order to clarify the complex relationships between these microorganisms and PD.

Examining the complex Interplay between gut microbiota abundance and short-chain fatty acid production in amyotrophic lateral sclerosis patients shortly after onset of disease

This study aimed to assess differences in the enteral microbiome of relatively recent-onset amyotrophic lateral sclerosis (ALS) patients (< 6-15 months since symptom onset) compared to healthy individuals, focusing on short-chain fatty acids (SCFAs) as potential mediators of host metabolism. We included 28 volunteers (16 ALS, 12 controls) with informed consent. No significant effect of ALS on alpha diversity (measuring the variety and abundance of species within a single sample, and indicating the health and complexity of the microbiome) was observed, but ALS patients had higher abundances of Fusobacteria and Acidobacteria. ALS subtypes influenced specific species, with increased Fusobacteria and Tenericutes in spinal ALS compared to bulbar ALS. ALS patients showed increased Enterobacter, Clostridium, Veillonella, Dialister, Turicibacter, and Acidaminococcus species and decreased Prevotella, Lactobacillus, and Butyricimonas. Correlations between species varied between ALS patients and healthy individuals and among ALS subtypes. No significant differences in SCFA concentrations were found, but spinal ALS samples showed a trend towards decreased propionate content. Relationships between SCFAs and phyla colonization differed by disease status. This study suggests distinct enteral microbiome characteristics in ALS patients, though the implications are unclear. Further research is needed to determine if these differences are causative or consequential and to explore their potential as diagnostic or therapeutic targets. The study also underscores the heterogeneity of microbiome constraints in ALS and the need for more research into ALS and SCFA metabolism.

Balancing the Oral-Gut-Brain Axis with Diet

Background: The oral microbiota is the second largest microbial community in humans. It contributes considerably to microbial diversity and health effects, much like the gut microbiota. Despite physical and chemical barriers separating the oral cavity from the gastrointestinal tract, bidirectional microbial transmission occurs between the two regions, influencing overall host health. Method: This review explores the intricate interplay of the oral-gut-brain axis, highlighting the pivotal role of the oral microbiota in systemic health and ageing, and how it can be influenced by diet. Results: Recent research suggests a relationship between oral diseases, such as periodontitis, and gastrointestinal problems, highlighting the broader significance of the oral-gut axis in systemic diseases, as well as the oral-gut-brain axis in neurological disorders and mental health. Diet influences microbial diversity in the oral cavity and the gut. While certain diets/dietary components improve both gut and oral health, others, such as fermentable carbohydrates, can promote oral pathogens while boosting gut health. Conclusions: Understanding these dynamics is key for promoting a healthy oral-gut-brain axis through dietary interventions that support microbial diversity and mitigate age-related health risks.

Association of periodontitis with all-cause and cause-specific mortality among individuals with depression: a population-based study

To detect the association between periodontitis and all-cause as well as cause-specific mortality rates among adults diagnosed with depression. Participants diagnosed with depression were selected from NHANES across three periods (1988-1994; 1999-2004; 2009-2014). Cox proportional hazards and Weibull accelerated failure time (AFT) models were utilized to calculate hazard ratios (HRs), time ratios (TRs), and their 95% confidence intervals (CIs) to evaluate the association between moderate-to-severe periodontitis and all-cause as well as cause-specific mortality among participants with depression. white blood counts and C-reactive protein were used to assess the mediating role of systemic inflammation. Among the 1,189 participants with a median follow-up of 9.25 years, 133 deaths were recorded. After adjusting for multiple variables, moderate-to-severe periodontitis was obvious associated with an increased risk of cancer-related mortality in individuals with depression (Cox: HR 3.22, 95% CI 1.51-6.83, P = 0.002; AFT: TR 0.70, 95% CI 0.52-0.94, P = 0.017). Neither WBC nor CRP significantly mediate the association between periodontitis and cancer-related mortality. The risk of cancer-related mortality rose with the severity of periodontitis (P for trend = 0.021). However, no association was observed between moderate-to-severe periodontitis and other kinds of mortality. Moderate-to-severe periodontitis is linked to an elevated risk of cancer-related mortality among adults diagnosed with depression, with the mortality risk increasing alongside the severity of periodontitis. No significant mediating effect of systemic inflammation was found in this association. These findings highlight the importance of addressing periodontal health in individuals with depression. By uncovering the association between periodontitis and mortality in this population, our study underscores the potential benefits of preventive dental care and periodontal treatment in reducing the risk of cancer-related mortality in individuals with depression.

Differentiation and regulation of CD4+ T cell subsets in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease, and its hallmark pathological features are the loss of dopaminergic (DA) neurons in the midbrain substantia nigra pars compacta (SNpc) and the accumulation of alpha-synuclein (α-syn). It has been shown that the integrity of the blood-brain barrier (BBB) is damaged in PD patients, and a large number of infiltrating T cells and inflammatory cytokines have been detected in the cerebrospinal fluid (CSF) and brain parenchyma of PD patients and PD animal models, including significant change in the number and proportion of different CD4+ T cell subsets. This suggests that the neuroinflammatory response caused by CD4+ T cells is an important risk factor for the development of PD. Here, we systematically review the differentiation of CD4+ T cell subsets, and focus on describing the functions and mechanisms of different CD4+ T cell subsets and their secreted cytokines in PD. We also summarize the current immunotherapy targeting CD4+ T cells with a view to providing assistance in the diagnosis and treatment of PD.

Relationship between human oral microbiome dysbiosis and neuropsychiatric diseases: An updated overview

The role of the gut-brain axis in mental health disorders has been extensively studied. As the oral cavity is the starting point of the digestive tract, the role that the oral microbiota plays in mental health disorders has gained recent attention. Oral microbiota can enter the bloodstream and trigger inflammatory responses or translocate to the brain through the trigeminal nerve or olfactory system. Hence, the concept of the oral microbiota-brain axis has emerged. Several hypotheses have been suggested that the oral microbiota can enter the gastrointestinal tract and affect the gut-brain axis; however, literature describing oral-brain communication remains limited. This review summarizes the characteristics of oral microbiota and its mechanisms associated with mental health disorders. Through a comprehensive examination of the relationship between oral microbiota and various neuropsychiatric diseases, such as anxiety, depression, schizophrenia, autism spectrum disorder, epilepsy, Parkinson's disease, and dementia, this review seeks to identify promising avenues of future research.

Therapeutics for neurodegenerative diseases by targeting the gut microbiome: from bench to bedside

The aetiologies and origins of neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD), are complex and multifaceted. A growing body of evidence suggests that the gut microbiome plays crucial roles in the development and progression of neurodegenerative diseases. Clinicians have come to realize that therapeutics targeting the gut microbiome have the potential to halt the progression of neurodegenerative diseases. This narrative review examines the alterations in the gut microbiome in AD, PD, ALS and HD, highlighting the close relationship between the gut microbiome and the brain in neurodegenerative diseases. Processes that mediate the gut microbiome-brain communication in neurodegenerative diseases, including the immunological, vagus nerve and circulatory pathways, are evaluated. Furthermore, we summarize potential therapeutics for neurodegenerative diseases that modify the gut microbiome and its metabolites, including diets, probiotics and prebiotics, microbial metabolites, antibacterials and faecal microbiome transplantation. Finally, current challenges and future directions are discussed.

Exploring the causal relationship between B lymphocytes and Parkinson's disease: a bidirectional, two-sample Mendelian randomization study

Parkinson's disease (PD) is a neurodegenerative disorder with extensive involvement of motor symptoms, imposing a heavy economic burden on patients and society. B lymphocytes, a group of immune cells associated with humoral immunity, have been shown to be involved in the pathogenesis of PD. However, the causal relationship and potential pathogenic effects of B cell in PD remain unclear. Based on the three core hypotheses of the Mendelian randomization (MR) study, we explored causal associations between 190 B-cell immunological traits and 482,730 European individuals (Ncase = 33,674, Ncontrol = 449,056) from genome wide association studies by means of the two-sample bidirectional MR method. The inverse‑variance weighted method was selected as the main approach when conducting MR analysis. Finally, the results were verified by the heterogeneity and horizontal pleiotropy analyses. Five B-cell immunological phenotypes were nominally associated with PD at the significance threshold of P < 0.05. Concretely, IgD + CD38- B cell %lymphocyte (OR 1.052, 95% CI 1.001-1.106, P = 0.046), CD20 on IgD- CD24- B cell (OR 1.060, 95% CI 1.005-1.117, P = 0.032), CD38 on IgD+ CD24- B cell (OR 1.113, 95% CI 1.028-1.206, P = 0.009), and BAFF-R on CD20- B cell (OR 1.093, 95% CI 1.010-1.184, P = 0.027) were identified as risk factors for PD. Instead, CD38 on Plasma Blast-Plasma Cell (OR 0.894, 95% CI 0.802-0.996, P = 0.043) was proved to be protective. However, there is no statistically significant correlation between B cell and PD after Bonferroni correction. The results of reverse MR were negative, avoiding the reverse causal effects. Eventually, the association results were identified as stable across several sensitivity analyses. Briefly, our study might demonstrate the key factor of B cells in PD. Further studies are warranted to clarify the associations for early identification and immunotherapeutic development in PD patients.