Lifetime physical activity influences Parkinson's disease progression.

Introduction: Past studies suggested that Parkinson's disease (PD) patients who engage in physical activity (PA) after diagnosis have slower motor progression. Here, we examine the influence of lifetime PA prior to PD onset on motor, cognitive, and overall functional decline among PD patients.

Methods: For 495 participants in the Parkinson's Environment and Gene (PEG) studies, we collected PA-related measures through interviews and quantified these using metabolic equivalents (MET) scores.

Genome-wide meta-analysis of short-tandem repeats for Parkinson's disease risk using genotype imputation.

Idiopathic Parkinson's disease is determined by a combination of genetic and environmental factors. Recently, the first genome-wide association study on short-tandem repeats in Parkinson's disease reported on eight suggestive short-tandem repeat-based risk loci ( = 5.3 × 10), of which four were novel, i.

Untargeted serum metabolic profiling of diabetes mellitus among Parkinson's disease patients.

Type 2 diabetes mellitus (T2DM) is a common comorbidity among Parkinson's disease (PD) patients. Yet, little is known about dysregulated pathways that are unique in PD patients with T2DM. We applied high-resolution metabolomic profiling in serum samples of 636 PD and 253 non-PD participants recruited from Central California.

Lysosomal genes contribute to Parkinson's disease near agriculture with high intensity pesticide use.

Parkinson's disease (PD), the second most common neurodegenerative disorder, develops sporadically, likely through a combination of polygenic and environmental factors. Previous studies associate pesticide exposure and genes involved in lysosomal function with PD risk. We evaluated the frequency of variants in lysosomal function genes among patients from the Parkinson's, Environment, and Genes (PEG) study with ambient pesticide exposure from agricultural sources.

Diet and the gut microbiome in patients with Parkinson's disease.

It has been suggested that gut microbiota influence Parkinson's disease (PD) via the gut-brain axis. Here, we examine associations between diet and gut microbiome composition and its predicted functional pathways in patients with PD. We assessed gut microbiota in fecal samples from 85 PD patients in central California using 16S rRNA gene sequencing.

Ambient long-term exposure to organophosphorus pesticides and the human gut microbiome: an observational study.

Background: Organophosphorus pesticides (OP) have been associated with various human health conditions. Animal experiments and in-vitro models suggested that OP may also affect the gut microbiota. We examined associations between ambient chronic exposure to OP and gut microbial changes in humans.

Agricultural paraquat dichloride use and Parkinson's disease in California's Central Valley.

Background: Paraquat dichloride is currently among the most widely used commercial herbicides in the USA. In the present study, we provide epidemiological assessment of ambient paraquat exposure and Parkinson's disease (PD) risk in a population-based study of PD in agricultural regions of Central California.

Methods: Based on 829 PD patients and 824 community controls, we assessed associations between ambient paraquat dichloride exposure and PD.

Untargeted serum metabolomics reveals novel metabolite associations and disruptions in amino acid and lipid metabolism in Parkinson's disease.

Background: Untargeted high-resolution metabolomic profiling provides simultaneous measurement of thousands of metabolites. Metabolic networks based on these data can help uncover disease-related perturbations across interconnected pathways.

Objective: Identify metabolic disturbances associated with Parkinson's disease (PD) in two population-based studies using untargeted metabolomics.

Traffic-related air pollution and Parkinson's disease in central California.

Background: Prior studies suggested that air pollution exposure may increase the risk of Parkinson's Disease (PD). We investigated the long-term impacts of traffic-related and multiple sources of particulate air pollution on PD in central California.

Methods: Our case-control analysis included 761 PD patients and 910 population controls.

Diet quality and Parkinson's disease: Potential strategies for non-motor symptom management.

Introduction: Parkinson's disease (PD) is now considered a systemic disease, and some phenotypes may be modifiable by diet. We will compare the diet quality and intake of specific nutrients and food groups of PD patients with household and community controls to examine how diet may influence PD clinical features.

Methods: We conducted a case-control study of 98 PD patients and 83 controls (household = 53; community = 30) in central California, assessing dietary habits over the past month and calculating the Healthy Eating Index (HEI)-2015.

A pesticide and iPSC dopaminergic neuron screen identifies and classifies Parkinson-relevant pesticides.

Parkinson's disease (PD) is a complex neurodegenerative disease with etiology rooted in genetic vulnerability and environmental factors. Here we combine quantitative epidemiologic study of pesticide exposures and PD with toxicity screening in dopaminergic neurons derived from PD patient induced pluripotent stem cells (iPSCs) to identify Parkinson's-relevant pesticides. Agricultural records enable investigation of 288 specific pesticides and PD risk in a comprehensive, pesticide-wide association study.

Ethnicity and Parkinson's Disease: Motor and Nonmotor Features and Disease Progression in Latino Patients Living in Rural California.

Background: Parkinson's disease (PD) is the second most common neurodegenerative disorder among older adults worldwide. Currently, studies of PD progression rely primarily on White non-Latino (WNL) patients. Here, we compare clinical profiles and PD progression in Latino and WNL patients enrolled in a community-based study in rural Central California.

Proximity to residential and workplace pesticides application and the risk of progression of Parkinson's diseases in Central California.

Background: Pesticide exposure has consistently been associated with Parkinson's disease (PD) onset. Yet, fewer epidemiologic studies have examined whether pesticides influence PD motor and non-motor symptom progression.

Objectives: Using a geographic information system tool that integrates agricultural pesticide use reports and land use records to derive ambient exposures at residences and workplaces, we assessed associations between specific pesticides previously related to PD onset with PD symptom progression in two PD patient cohorts living in agricultural regions of California.

Parkinson's Disease and the Gut Microbiome in Rural California.

Background: Increasing evidence connects the gut microbiome to Parkinson's disease (PD) etiology, but little is known about microbial contributions to PD progression and its clinical features.

Objective: We aim to explore the association between the gut microbiome with PD, and the microbial association with PD-specific clinical features.

Methods: In a community-based case-control study of 96 PD patients and 74 controls, microbiome data were obtained from 16S rRNA gene sequencing of fecal samples, and analyzed for microbial diversity, taxa abundance, and predicted functional pathways that differed in PD patients and controls, and their association with PD-specific features (disease duration, motor subtypes, L-DOPA daily dose, and motor function).

Neurotoxicity of diesel exhaust extracts in zebrafish and its implications for neurodegenerative disease.

Long-term air pollution (AP) exposure, including diesel exhaust exposure, is increasingly being recognized as a major contributor to the development of neurodegenerative diseases such as Parkinson's and Alzheimer's disease. How AP increases the risk of neurodegeneration is not well understood but might include direct neurotoxicity and CNS inflammation. We investigated the impact of diesel exhaust particulate extract (DEPe) exposure on the brain and the mechanisms by which microglia and astroglia might mediate neuronal changes.

Immune system disruptions implicated in whole blood epigenome-wide association study of depression among Parkinson's disease patients.

Although Parkinson's Disease (PD) is typically described in terms of motor symptoms, depression is a common feature. We explored whether depression influences blood-based genome-wide DNA methylation (DNAm) in 692 subjects from a population-based PD case-control study, using both a history of clinically diagnosed depression and current depressive symptoms measured by the geriatric depression scale (GDS). While PD patients in general had more immune activation and more accelerated epigenetic immune system aging than controls, the patients experiencing current depressive symptoms (GDS≥5) showed even higher levels of both markers than patients without current depressive symptoms (GDS<5).