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

Effectiveness of the Roy adaptation model-based nursing intervention in improving physiological, psychological, and social outcomes in patients with Parkinson's disease

OBJECTIVE

This study aimed to evaluate the effectiveness of a comprehensive nursing intervention based on Roy's Adaptation Model (RAM) in improving quality of life, psychological adaptation, and social functioning in patients with Parkinson's disease (PD).

METHODS

A total of 96 patients with idiopathic PD were randomly assigned to the RAM group or the usual care group. The RAM intervention included a 3-month program addressing physiological, psychological, role function, and interdependence adaptation needs. Outcomes were assessed at baseline, 1 month, 3 months, and 6 months using the Scale for Outcomes in Parkinson' s Disease - Autonomic Symptoms (SCOPA-AUT), Pittsburgh Sleep Quality Index (PSQI), Fatigue Severity Scale (FSS), Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI), General Self-Efficacy Scale (GSES), Parkinson' s Disease Social Functioning Scale (PDSFS), Multidimensional Scale of Perceived Social Support (MSPSS), and Parkinson' s Disease Questionnaire-39 (PDQ-39).

RESULTS

The RAM group demonstrated significant improvements in autonomic function, sleep quality, and fatigue compared to the usual care group (SCOPA-AUT, PSQI, and FSS). Psychological adaptation improved with reduced depressive and anxiety symptoms (BDI-II and BAI) and increased self-efficacy (GSES). Role function and interdependence adaptation were significantly enhanced, as indicated by higher PDSFS and MSPSS scores. Quality of life, assessed using PDQ-39, showed significant and sustained improvements across all domains, including mobility, activities of daily living, emotional well-being, and social support.

CONCLUSION

The RAM-based care intervention effectively enhanced physiological and psychological outcomes, social functioning, and quality of life in PD patients, highlighting its value in promoting holistic, patient-centered nursing care.

CLINICAL TRIAL NUMBER

Not applicable.

Identifying molecular pathways of olfactory dysfunction in Parkinson's disease through a systems biology framework

The sense of smell is essential for human perception. Olfactory function declines with increasing age, affecting a substantial portion of the elderly population, and this decline is more pronounced in men. This reduction can be attributed to anatomical and degenerative changes in the brain and olfactory receptors. There is robust clinical evidence indicating an association between olfactory perception decline/deficit (OPD) and major neurodegenerative diseases, with severe deficits observed in Alzheimer's and Parkinson's disease and milder effects noted in other conditions. However, its molecular bases have not yet been identified. Here, we explored the molecular connection between OPD and Parkinson's disease by conducting data-mining, gene enrichment analysis, and examining protein-interaction networks using systems biology approaches. We found pathways associated with both OPD and Parkinson's disease, identifying over 300 relevant genes. These genes belong to biologically relevant gene families, including transporters, kinases, nuclear receptors, transcription factors, and olfactory and other G protein-coupled receptors. Functional enrichment analysis revealed shared biological processes between OPD and Parkinson's disease, such as synaptic signalling and neuroinflammation. Mitochondrial gene enrichment was unique to Parkinson's. Both conditions exhibited a scarcity of associated genes on the Y chromosome but an even distribution on the non-pseudoautosomal region of the X chromosome, potentially explaining sex prevalence differences. In conclusion, our study suggests olfactory testing may help diagnose cognitive decline in neurodegenerative diseases. Further research is needed to understand the connection between OPD, aging, and other diseases and to examine olfactory performance in screening individuals at risk of Parkinson's disease and similar conditions.

Pervasive glycative stress links metabolic imbalance and muscle atrophy in early-onset Parkinson's disease

OBJECTIVE

Parkinson's disease (PD) is recognized as a systemic condition, with clinical features potentially modifiable by dietary intervention. Diets high in saturated fats and refined sugars significantly increase PD risk and exacerbate motor and non-motor symptoms, yet precise metabolic mechanisms are unclear. Our objective here was to investigate the interplay between diet and PD-associated phenotypes from a metabolic perspective.

METHODS

We explored PARK7 KO mice under chronic glycative stress induced by prolonged high-fat high-sucrose (HFHS) diet. We investigated metabolic consequences by combining classical metabolic phenotyping (body composition, glucose tolerance, indirect calorimetry, functional assays of isolated mitochondria) with metabolomics profiling of biospecimens from mice and PD patients.

RESULTS

We found this obesogenic diet drives loss of fat and muscle mass in early-onset PD mice, with a selective vulnerability of glycolytic myofibers. We show that PD mice and early-onset familial PD patients are under pervasive glycative stress with pathological accumulation of advanced glycation end products (AGEs), including N-α-glycerinylarginine (α-GR) and N-α-glycerinyllysine (α-GK), two previously unknown glycerinyl-AGE markers.

CONCLUSIONS

Our results offer the first proof for a direct link between diet, accumulation of AGEs and genetics of PD. We also expand the repertoire of clinically-relevant glycative stress biomarkers to potentially define at-risk patients before neurological or metabolic symptoms arise, and/or to monitor disease onset, progression, and effects of interventions.

Challenges in studying air pollution to neurodegenerative diseases

Exposure to ambient air pollution is ubiquitous and unavoidable. While associations between air pollution and cardiometabolic diseases are well-established, its role in neurodegenerative diseases, such as Alzheimer's disease and related dementias (ADRD) and Parkinson's disease (PD), has only recently begun to emerge. This narrative review provides an overview of current findings and discusses challenges and opportunities for future epidemiologic research. Mechanistically, air pollution may contribute to ADRD and PD through neuroinflammation, oxidative stress, and cerebrovascular damage. Long-term exposure to high levels of air pollution may increase the risk of ADRD and PD. Over the past 20 years, more than 50 studies have examined air pollution and ADRD, while fewer studies have focused on PD. Although the estimated effects are modest in size, they translate into a substantial number of affected individuals due to the widespread nature of the exposure and an increasingly aging population worldwide. Future research should extend exposure periods to cover younger and middle ages, estimate the effects of long-term cumulative exposures, and evaluate moderators and mediators, such as diet, physical activity, green space, and noise. More studies are also needed to include large and diverse populations, including those with special vulnerabilities and emerging exposures like wildfire smoke.

Stress-related neurodegenerative diseases: Molecular mechanisms implicated in neurodegeneration and therapeutic strategies

Chronic stress is a striking cause of major neurodegenerative diseases disorders (NDDs). These diseases share several common mechanisms regarding to disease pathology, in spite of they have various properties and clinical manifestations. NDDs are defined by progressive cognitive decline, and stress contribute to the promotion and progression of disease. In addition, various pathways such as production of reactive oxygen species (ROS), mitochondrial dysfunction, and neurodegeneration are the main crucial hallmarks to develop common NDDs, resulting in neuronal cell death. Although the exact mechanisms of NDDs are underexplored, the potential neuroprotective critical role of such therapies in neuronal loss the treatment of NDDs are not clear. In this regard, researchers investigate the neuroprotective effects of targeting underlying cascade to introduce a promising therapeutic option to NDDs. Herein, we provide an overview of the role of non-pharmacological treatments against oxidative stress, mitochondrial symbiosis, and neuroinflammation in NDDs, mainly discussing the music, diet, and exercise effects of targeting pathways.

Association between Mediterranean diet adherence and Parkinson's disease: a systematic review and meta-analysis

BACKGROUND AND AIMS

Parkinson's disease (PD) is a chronic neurodegenerative disorder, and past research suggests that adherence to the Mediterranean diet (MD) may influence the risk of PD. However, there are varying conclusions among different studies regarding the correlation between long-term adherence to the MD and the occurrence of PD. This meta-analysis aimed to investigate the association between MD adherence and PD incidence.

METHODS

This meta-analysis was registered on PROSPERO (CRD42024520410). We searched PubMed, Embase, Web of Science, and Cochrane databases to identify observational studies, including prospective cohorts, case-control, and cross-sectional studies, up to February 2024. Studies reported on MD adherence were included, with MD adherence categorized through a quantifying score or index. The pool odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for the highest versus the lowest categories of MD score in relation to PD risk, using random-effects models. Additionally, bias assessment, heterogeneity assessment, sensitivity analysis, and subgroup analysis were performed. A total of 12 studies were included in the meta-analysis.

RESULTS

The overall effect size of PD risk was as follows: compared to the lowest adherence to the MD, the highest adherence to MD showed a significant negative correlation with the incidence of PD, with an overall OR of 0.75 (95% CI: 0.66, 0.84). Specifically, in studies diagnosing PD, the overall OR was 0.83 (95% CI: 0.74, 0.94), while in studies diagnosing prodromal Parkinson's disease (pPD), the overall OR was 0.67 (95%CI: 0.59, 0.76). For individuals aged <60 years, the overall OR was 0.70 (95%CI: 0.62, 0.78), whereas, for those aged ≥60 years, the overall OR was 0.86 (95%CI: 0.74, 0.99).

CONCLUSIONS

The evidence from this meta-analysis demonstrates a significant negative correlation between adherence to MD patterns and the risk of PD, suggesting that the MD may serve as a protective factor for PD. This dietary pattern may be particularly beneficial in reducing the risk of pPD.

Associations of Dietary Intakes with Parkinson's Disease: Findings from a Cross-Sectional Study

BACKGROUND

Parkinson's disease (PD) is a chronic progressive neurodegenerative disease, and the exact etiology of PD has not been fully elucidated. Changes in dietary patterns play an important role in the onset and progression of PD. However, the association between specific dietary factors and PD remains unclear.

METHODS

A total of 14,309 subjects from the National Health and Nutrition Examination Survey (NHANES) (2007-2016) were included. Logistic regression was used to analyze the association between 34 nutrients and PD. The regression model was adjusted for potential confounders and effect modifiers including age, gender, race, education, hypertension, and stroke.

RESULTS

The data showed negative associations of the intake of protein (0.99 (0.98, 1.00), p = 0.018), fiber (0.96 (0.93, 0.99), p = 0.003), vitamin E (0.91 (0.86, 0.97), p = 0.005), copper (0.55 (0.36, 0.86), p = 0.009) with PD. Alpha carotene (p = 0.042), beta-carotene (p = 0.006), phosphorus (p = 0.018), magnesium (p = 0.002), sodium (p = 0.035), potassium (p = 0.001) had a potential negative correlation with PD. The intake of carbohydrate, sugars, fat, cholesterol, vitamin A, beta-cryptoxanthin, lycopene, lutein zeaxanthin, vitamin B1, vitamin B2, niacin, vitamin B6, folate, vitamin B12, vitamin C, vitamin D, vitamin K, calcium, iron, zinc, selenium, caffeine, theobromine, alcohol was not associated with PD (p > 0.05).

CONCLUSIONS

Some specific dietary elements are associated with PD, and supplementation of dietary elements may have potentially beneficial effects. However, the observed associations between dietary factors and PD may be influenced by changes in diet resulting from the disease itself, rather than diet influencing PD risk. Further longitudinal studies are needed to establish causal relationships and directionality.

Associations between Constipation and Use of Levodopa with Nutritional Status, Polypharmacy, and Stage of Parkinson's Disease

INTRODUCTION

Parkinson's disease (PD) is a highly prevalent disease characterized by motor and non-motor symptoms; the latter include constipation, which is considered a prodromal symptom. On the other hand, sarcopenia, polypharmacy, and malnutrition due to deficits are common in PD and lead to poorer health and quality of life.

OBJECTIVE

to associate constipation and use of levodopa with nutritional status, sarcopenia, duration and stage of the disease, and polypharmacy in individuals with PD.

MATERIALS AND METHODS

analytical cross-sectional observational study where an online survey was applied to 161 people suffering from PD.

RESULTS

a significant association is observed between constipation and BMI (p = 0.022), as well as between the use of levodopa with BMI (p = 0.049) and polypharmacy (p = 0.046). On the other hand, there is a relationship between the average time of PD diagnosis and constipation (p = 0.0047). Finally, there is a relationship between SARC-F score applied to those over 60 years of age (p = 0.0446) and the use of levodopa. Having sarcopenia, being overweight, and having had the disease for less than five years is associated with a higher probability of experiencing constipation, according to the logistic regression analysis (p > 0.005).

CONCLUSION

nutritional assessment and subsequent follow-up is of vital importance to avoid complications that could be associated with levodopa use, constipation, and sarcopenia.

The Impact of Diet on Parkinson's Disease: A Systematic Review

Parkinson's disease (PD) is a progressive neurodegenerative disorder with complex etiology. Emerging evidence suggests that diet may play a role in PD risk, progression, and symptom management. However, the relationship between dietary factors and PD remains poorly understood. This systematic review aimed to synthesize and evaluate the current evidence on the associations between dietary patterns, specific nutrients, and PD risk, progression, and symptom management. We conducted a comprehensive literature search in major databases for studies published up to 2024. Eligible studies included prospective cohorts, case-control studies, randomized controlled trials, and cross-sectional analyses investigating the relationship between diet and PD. Data extraction and quality assessment were performed independently by two reviewers. Eleven studies met the inclusion criteria. Adherence to healthy dietary patterns, particularly those rich in fruits, vegetables, whole grains, and fish, was consistently associated with reduced PD risk. Conversely, Western-style diets high in processed foods and red meat were linked to increased risk. Specific nutrients, including antioxidants and vitamins K and C, showed potential neuroprotective effects, while high iron intake was associated with increased PD risk. Diet quality was found to influence PD symptoms, particularly non-motor symptoms like constipation. Emerging evidence suggested a role for the gut microbiome in mediating diet-PD relationships. Specialized diets, such as ketogenic and low-carbohydrate diets, showed promise in managing PD symptoms in small-scale studies. This review provides evidence for the significant role of diet in PD risk, progression, and symptom management. Dietary interventions have the potential to serve as complementary approaches to existing PD therapies. However, the complex nature of the diet-PD relationship necessitates further research, particularly well-designed long-term randomized controlled trials, to develop evidence-based, personalized dietary recommendations for PD prevention and management.

Interplay of human gastrointestinal microbiota metabolites: Short-chain fatty acids and their correlation with Parkinson's disease

Short-chain fatty acids (SCFAs) are, the metabolic byproducts of intestinal microbiota that, are generated through anaerobic fermentation of undigested dietary fibers. SCFAs play a pivotal role in numerous physiological functions within the human body, including maintaining intestinal mucosal health, modulating immune functions, and regulating energy metabolism. In recent years, extensive research evidence has indicated that SCFAs are significantly involved in the onset and progression of Parkinson disease (PD). However, the precise mechanisms remain elusive. This review comprehensively summarizes the progress in understanding how SCFAs impact PD pathogenesis and the underlying mechanisms. Primarily, we delve into the synthesis, metabolism, and signal transduction of SCFAs within the human body. Subsequently, an analysis of SCFA levels in patients with PD is presented. Furthermore, we expound upon the mechanisms through which SCFAs induce inflammatory responses, oxidative stress, abnormal aggregation of alpha-synuclein, and the intricacies of the gut-brain axis. Finally, we provide a critical analysis and explore the potential therapeutic role of SCFAs as promising targets for treating PD.

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. Diet quality was assessed by calculating the Healthy Eating Index 2015 (HEI-2015) based on the Diet History Questionnaire II. We examined associations of diet quality, fiber, and added sugar intake with microbial diversity, composition, taxon abundance, and predicted metagenomic profiles, adjusting for age, sex, race/ethnicity, and sequencing platform. Higher HEI scores and fiber intake were associated with an increase in putative anti-inflammatory butyrate-producing bacteria, such as the genera Butyricicoccus and Coprococcus 1. Conversely, higher added sugar intake was associated with an increase in putative pro-inflammatory bacteria, such as the genera Klebsiella. Predictive metagenomics suggested that bacterial genes involved in the biosynthesis of lipopolysaccharide decreased with higher HEI scores, whereas a simultaneous decrease in genes involved in taurine degradation indicates less neuroinflammation. We found that a healthy diet, fiber, and added sugar intake affect the gut microbiome composition and its predicted metagenomic function in PD patients. This suggests that a healthy diet may support gut microbiome that has a positive influence on PD risk and progression.