Treatment of Advanced Parkinson's Disease

Unraveling neuroprotection in Parkinson's disease: Nrf2-Keap1 pathway's vital role amidst pathogenic pathways

Parkinson's disease (PD) is an age-related chronic neurological condition characterized by progressive degeneration of dopaminergic neurons and the presence of Lewy bodies, primarily composed of alpha-synuclein and ubiquitin. The pathophysiology of PD encompasses alpha-synuclein aggregation, oxidative stress, neuroinflammation, mitochondrial dysfunction, and impaired autophagy and ubiquitin-proteasome systems. Among these, the Keap1-Nrf2 pathway is a key regulator of antioxidant defense mechanisms. Nrf2 has emerged as a crucial factor in managing oxidative stress and inflammation, and it also influences ubiquitination through p62 expression. Keap1 negatively regulates Nrf2 by targeting it for degradation via the ubiquitin-proteasome system. Disruption of the Nrf2-Keap1 pathway in PD affects cellular responses to oxidative stress and inflammation, thereby playing a critical role in disease progression. In addition, the role of neuroinflammation in PD has gained significant attention, highlighting the interplay between immune responses and neurodegeneration. This review discusses the various mechanisms responsible for neuronal degeneration in PD, with a special emphasis on the neuroprotective role of the Nrf2-Keap1 pathway. Furthermore, it explores the implications of inflammopharmacology in modulating these pathways to provide therapeutic insights for PD.

Effects of Safinamide on Motor and Non-Motor Symptoms in Patients with Parkinson's Disease and Motor Fluctuations

INTRODUCTION

Parkinson's disease (PD) involves the progressive loss of dopaminergic neurons, leading to motor and non-motor symptoms that significantly impact patients' quality of life. Safinamide modulates dopaminergic and glutamatergic systems, offering a promising treatment approach.

METHODS

This meta-analysis evaluated the efficacy of safinamide as an add-on therapy to levodopa for PD patients with motor fluctuations. Following PRISMA guidelines, literature searches were conducted in PubMed and Embase (2014-2022). Inclusion criteria were studies on adult PD patients receiving safinamide with levodopa. Outcomes included on-time without troublesome dyskinesia, off-time, UPDRS Part III motor scores, UPDRS Part II activities of daily living scores, PDQ-39 emotional well-being, and GRID-HAMD scores.

RESULTS

Among thirteen eligible studies, safinamide significantly improved on-time without troublesome dyskinesia at 100 mg/day (mean difference [MD]: -0.90; 95% CI: -1.12 to -0.67; p < 0.00001) and 50 mg/day (MD: -0.77; 95% CI: -1.21 to -0.34; p = 0.0005) compared to placebo. It also reduced off-time (100 mg/day: MD: -0.94; 95% CI: -1.19 to -0.70; p < 0.00001; 50 mg/day: MD: -0.72; 95% CI: -1.03 to -0.41; p < 0.00001) and improved UPDRS-III motor scores (100 mg/day: MD: -3.01; 95% CI: -4.15 to -1.86; p < 0.00001; 50 mg/day: MD: -2.93; 95% CI: -5.14 to -0.71; p = 0.001). Mood improvements were noted in PDQ-39 emotional well-being scores (MD: -5.22; 95% CI: -6.90 to -3.54) and GRID-HAMD scores (MD: -0.60; 95% CI: -0.95 to -0.25; p = 0.0009). Safinamide also positively affected pain (RR: 1.10; 95% CI: 1.03 to 1.18).

CONCLUSION

Compared to placebo, safinamide significantly benefits motor and non-motor symptoms in PD patients, but further research is necessary to fully explore its therapeutic potential.

Safinamide as adjunctive therapy to levodopa monotherapy for patients with Parkinson's disease with wearing-off: The Japanese observational J-SILVER study

BACKGROUND

Safinamide is an effective adjunctive therapy for wearing-off in Parkinson's disease (PD); however, evidence is lacking in older patients and those in the early stages of wearing-off. This study evaluated the efficacy and safety of safinamide as adjunctive therapy in patients with PD treated with levodopa monotherapy in clinical practice.

METHODS

This multicentre, open-label observational study was conducted at five sites in Japan. Patients diagnosed with PD and wearing-off initiated safinamide as adjunctive therapy with levodopa monotherapy. Efficacy endpoints were mean changes in Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part I, III, and IV scores; daily ON-time without dyskinesia using 24-h patient symptom diaries; and 39-item Parkinson's Disease Questionnaire (PDQ-39) scores at 18 weeks of treatment.

RESULTS

In total, 24 patients initiated safinamide (66.7% were aged ≥75 years); the mean duration of wearing-off was 1.2 years. MDS-UPDRS Part III total score, Part IV total score, and PDQ-39 summary index decreased significantly from baseline (mean change -7.0 [p = 0.012], -2.4 [p = 0.007] and - 5.3 [p = 0.012], respectively). There was a non-statistically significant increase of 1.55 h in mean daily ON-time without dyskinesia. Numerical Rating Scale total score for pain (p = 0.015), and scores for OFF-period pain (p = 0.012) and nocturnal pain (p = 0.021) subdomains were significantly improved in the subgroup with pain. Most reported adverse events were classified as mild.

CONCLUSION

Safinamide improved motor and non-motor symptoms and quality of life-related measures in older patients with PD in the early stages of wearing-off without new safety concerns.

STUDY REGISTRATION

University Hospital Medical Information Network in Japan; study ID: UMIN000044341.

Feasibility of Somato-Cognitive Coordination Therapy Using Virtual Reality for Patients with Advanced Severe Parkinson's Disease

 This feasibility study enrolled 20 patients with advanced severe Parkinson's disease (PD) to evaluate somato-cognitive coordination therapy (SCCT) using virtual reality. Focusing on the safety and tolerability of SCCT, 17 patients (76±9 years old and 64.7% male) completed the 3-month trial. Key observations included absence of adverse events and tolerability of the participants to SCCT despite initial apprehensions and minor adjustments in medication. Physical functions showed no significant deterioration, suggesting the safety of SCCT. In conclusion, SCCT emerges as feasible and well-tolerated intervention in advanced severe PD, requiring further research to assess its therapeutic efficacy.

Research progress in the molecular mechanism of ferroptosis in Parkinson's disease and regulation by natural plant products

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder of the central nervous system after Alzheimer's disease. The current understanding of PD focuses mainly on the loss of dopamine neurons in the substantia nigra region of the midbrain, which is attributed to factors such as oxidative stress, alpha-synuclein aggregation, neuroinflammation, and mitochondrial dysfunction. These factors together contribute to the PD phenotype. Recent studies on PD pathology have introduced a new form of cell death known as ferroptosis. Pathological changes closely linked with ferroptosis have been seen in the brain tissues of PD patients, including alterations in iron metabolism, lipid peroxidation, and increased levels of reactive oxygen species. Preclinical research has demonstrated the neuroprotective qualities of certain iron chelators, antioxidants, Fer-1, and conditioners in Parkinson's disease. Natural plant products have shown significant potential in balancing ferroptosis-related factors and adjusting their expression levels. Therefore, it is vital to understand the mechanisms by which natural plant products inhibit ferroptosis and relieve PD symptoms. This review provides a comprehensive look at ferroptosis, its role in PD pathology, and the mechanisms underlying the therapeutic effects of natural plant products focused on ferroptosis. The insights from this review can serve as useful references for future research on novel ferroptosis inhibitors and lead compounds for PD treatment.

Cost-effectiveness of Levodopa-Carbidopa Intestinal Gel in treating people with Advanced Parkinson's disease

Advanced Parkinson's disease affects patients with existing Parkinson's disease by further deteriorating their physical and cognitive functions. In this commentary we critically assess an economic evaluation which compared the cost-effectiveness of levodopa/carbidopa intestinal gel against standard of care in treating patients with Advanced Parkinson's disease. While the economic evaluation indicated that levodopa/carbidopa intestinal gel could be cost-effective within the UK parameters, we highlight important limitations related to its design, modelling and analysis. Future research should consider the incorporation of a separate arm dedicated to the re-infusion of apomorphine on eligible Advanced Parkinson's disease patients, a wider set of levodopa/carbidopa intestinal gel adverse events and related costs, and a sub-group analysis on different socio-economic strata.

Mechanisms of Sleep/Wake Regulation under Hypodopaminergic State: Insights from MitoPark Mouse Model of Parkinson's Disease

Sleep/wake alterations are predominant in neurological and neuropsychiatric disorders involving dopamine dysfunction. Unfortunately, specific, mechanisms-based therapies for these debilitating sleep problems are currently lacking. The pathophysiological mechanisms of sleep/wake alterations within a hypodopaminergic MitoPark mouse model of Parkinson's disease (PD) are investigated. MitoPark mice replicate most PD-related sleep alterations, including sleep fragmentation, hypersomnia, and daytime sleepiness. Surprisingly, these alterations are not accounted for by a dysfunction in the circadian or homeostatic regulatory processes of sleep, nor by acute masking effects of light or darkness. Rather, the sleep phenotype is linked with the impairment of instrumental arousal and sleep modulation by behavioral valence. These alterations correlate with changes in high-theta (8-11.5 Hz) electroencephalogram power density during motivationally-charged wakefulness. These results demonstrate that sleep/wake alterations induced by dopamine dysfunction are mediated by impaired modulation of sleep by motivational valence and provide translational insights into sleep problems associated with disorders linked to dopamine dysfunction.

A Qualitative Analysis of Experiences With Food-Related Activities Among People Living With Parkinson Disease and Their Care-Partners

Objectives: The purpose of this qualitative study was to explore factors associated with the ability of people with PD to perform food-related activities (FRAs). Methods: Eleven dyads, older adults with Parkinson disease (PD) and their care-partners (n = 22), completed virtual semi-structured interviews guided by the Social Cognitive Theory (SCT) that were independently analyzed by two coders via directed content analysis. Results: The following themes were identified-(1) Personal: perception of a healthy diet, perception of how nutrition influences PD, confidence in following a healthy diet, and barriers to performing FRA; (2) Environmental: previous sources of nutrition information and willingness to changing their diet with a registered dietitian; and (3) Behavioral: modifications to FRA due to food-medication interactions, and skills necessary to maintain a healthy diet. Discussion: Findings from this study highlight the need for nutrition intervention research to inform evidence-based guidelines in order to provide tailored education for people with PD and care-partners.

Risk Factors for Delirium after Deep Brain Stimulation Surgery under Total Intravenous Anesthesia in Parkinson's Disease Patients

BACKGROUND

Postoperative delirium (POD) is associated with perioperative complications and mortality. Data on the risk factors for delirium after subthalamic nucleus deep brain stimulation (STN-DBS) surgery is not clarified in Parkinson's disease (PD) patients receiving total intravenous anesthesia. We aimed to investigate the risk factors for delirium after STN-DBS surgery in PD patients.

METHODS

The retrospective cohort study was conducted, including 131 PD patients who underwent STN-DBS for the first time under total intravenous anesthesia from January to December 2021. Delirium assessments were performed twice daily for 7 days after surgery or until hospital discharge using the confusion assessment method for the intensive care unit. Multivariate logistic regression analysis was used to determine the risk factor of POD.

RESULTS

In total, 22 (16.8%) of 131 patients were in the POD group, while the other 109 patients were in the Non-POD group. Multivariate logistic regression analysis showed that preoperative Mini-mental State Examination score [odds ratio = 0.855, 95% confidence interval = 0.768-0.951, p = 0.004] and unified Parkinson's disease rating scale part 3 (on state) score (odds ratio = 1.061, 95% confidence interval = 1.02-1.104, p = 0.003) were independently associated with delirium after surgery.

CONCLUSIONS

In this retrospective cohort study of PD patients, a lower Mini-mental State Examination score and a higher unified Parkinson's disease rating scale part 3 (on state) score were the independent risk factors for delirium after STN-DBS surgery in PD patients under total intravenous anesthesia.

Integrating virtual reality and exergaming in cognitive rehabilitation of patients with Parkinson disease: a systematic review of randomized controlled trials

INTRODUCTION

In recent years, growing attention is rising to virtual reality (VR) tools and exergaming in rehabilitation management of patients with Parkinson disease (PD). However, no strong evidence supports the effectiveness of these cutting-edge technologies on cognitive function and the integration of these promising tool in the rehabilitation framework of PD patients is still challenging. Therefore, the present systematic review of randomized controlled trials (RCTs) aimed at assessing the effects of VR and exergames/telerehabilitation in the cognitive rehabilitation management of patients with PD.

EVIDENCE ACQUISITION

PubMed, Scopus and Web of Science databases were systematically searched up to February 14^th, 2022, to identify RCTs assessing patients with PD undergoing cognitive rehabilitation including VR or exergames/telerehabilitation. The intervention was compared to conventional rehabilitation protocols. The primary outcome was cognitive function. The quality assessment was performed following the Version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2). PROSPERO registration code: CRD42022319788.

EVIDENCE SYNTHESIS

Out of 1419 identified studies, 66 articles were assessed for eligibility, and, at the end of the screening process, 10 studies were included in the present systematic review. Five RCTs (50%) assessed the exergaming devices, reporting significant positive results on cognitive outcomes scales (Trail Making test scale, Digit Span backward, MoCA, and MyCQ score). The other 5 RTCs (50%) assessed VR approaches, reporting significant improvement in executive functions. The RoB 2 showed an overall high risk of bias for the 40% of studies included.

CONCLUSIONS

Exergaming and VR might be considered promising rehabilitation interventions in the cognitive rehabilitation framework of PD patients. Further high-quality studies are needed to define the role of exergames and VR in a comprehensive rehabilitation approach aiming at improving the multilevel cognitive impairment characterizing patients with PD.

The impact of Parkinson's disease on results of primary total knee arthroplasty

Parkinson’s disease (PD) is a common neurodegenerative disorder.

When patients with PD undergo total knee arthroplasty (TKA) for knee osteoarthritis, poorer knee function and poorer quality of life are obtained than in matched cohorts (MCs). However, the degree of patient satisfaction is usually high.

The mean length of stay is 6.5% longer in patients with PD than in MCs.

Compared with MCs, patients with PD undergoing TKA have a 44% higher risk of complications.

In patients with PD, the overall complication rate is 26.3% compared with 10.5% in MCs; the periprosthetic joint infection rate is 6.5% in patients with PD vs 1.7% in MCs; and the periprosthetic fracture rate is 2.1% in patients with PD vs 1.7% in MCs.

The 90-day readmission rate is 16.29% in patients with PD vs 12.66% in MCs. More flexion contractures occur in patients with PD.

The rate of medical complications is 4.21% in patients with PD vs 1.24% in MCs, and the rate of implant-related complications is 5.09% in patients with PD vs 3.15% in MCs. At 5.3 years’ mean follow-up, the need for revision surgery is 23.6%.

The 10-year implant survival, taking revision of any of the components as an endpoint, is 89.7% in patients with PD vs 98.3% in MCs.

Effect of acupuncture for non-motor symptoms in patients with Parkinson's disease: A systematic review and meta-analysis

Background

Although non-motor symptoms of Parkinson's disease (PD) are serious, effective treatments are still lacking. Acupuncture may have clinical benefits for non-motor symptoms of PD patients, but high-quality evidence supporting this possibility is still limited. Hence, we conducted this meta-analysis to evaluate the effect of acupuncture treatment on non-motor symptoms in patients with PD.

Methods

Randomized controlled trials (RCTs) of acupuncture treatment for PD were retrieved from the following electronic databases: Medline (OVID), Embase (OVID), Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chinese BioMedical Literature Database, Chonqing VIP (CQVIP), and Wangfang database. Studies evaluating non-motor symptoms of PD were retrieved. Methodological quality was assessed using the Cochrane Handbook for Systematic Reviews of Interventions.

Results

A total of 27 RCTs were included, among which 8 outcomes related to non-motor symptoms were evaluated. The results showed that acupuncture combined with medication had benefits for PD-related insomnia relative to medication alone or sham acupuncture [standardized mean difference (SMD) = 0.517; 95% confidence interval (CI) = 0.242-0.793; p = 0.000], and acupuncture treatment had benefits at 8 weeks (SMD = 0.519; 95% CI = 0.181-0.857; p = 0.003). Regarding depression, acupuncture treatment was more effective (SMD = -0.353; 95% CI = -0.669 to -0.037; p = 0.029) within 2 months (SMD = -0.671; 95% CI = -1.332 to -0.011; p = 0.046). Regarding cognition, quality of life, and Unified Parkinson's Disease Rating Scale (UPDRS) I and II scores, acupuncture treatment was effective [SMD = 0.878, 95% CI = 0.046-1.711, p = 0.039; SMD = -0.690, 95% CI = -1.226 to -0.155, p = 0.011; weighted mean difference (WMD) = -1.536, 95% CI = -2.201 to -0.871, p = 0.000; WMD = -2.071, 95% CI = -3.792 to -0.351, p = 0.018; respectively]. A significant difference was not found in terms of PD-related constipation. Only one study evaluated PD-related fatigue.

Conclusion

The results of the analysis suggested that acupuncture treatment could ameliorate the symptoms of depression, quality of life, cognition, total mentation, behavior and mood, and activities of daily living in PD patients. Nevertheless, more prospective, well-designed RCTs with larger sample sizes are required to confirm our findings.