Anxiety: An ignored aspect of Parkinson’s disease lacking attention

Levodopa-synergistic CBT intervention improves Parkinson's disease with anxiety disorder by regulating the BDNF/PI3K/AKT pathway

BACKGROUND

Anxiety disorder is one of the most common and disabling neuropsychiatric syndromes in patients with Parkinson's disease (PD), seriously affecting the quality of life and prognosis of PD patients.

OBJECTIVE

The objective of this study was to analyze the risk factors for anxiety in PD patients and to evaluate the effectiveness of cognitive behavioral therapy (CBT) in treating PD with anxiety disorder (PDAD).

METHODS

Baseline data were recorded for 211 PD patients and 139 PDAD patients, and multi-factorial and independent risk factors for anxiety disorder in PD patients were analyzed. ​The 139 PDAD patients were divided into clinical testing (CMO) and CBT groups. Assessments were taken at baseline and after the end of the intervention. A 5-month follow-up survey was conducted after the intervention. The mouse PD model was induced by MPTP, and the anxiety state of mice was detected by rotarod test and open-field test. The expression of BDNF/PI3K/Akt protein in serum and mouse brain was detected by western blot.

RESULTS

PDAD patients had significantly higher HAMA scores than PD patients. PSQI, ESS, HAMD, SCOPA-AUT, UPDRS-III and Hoehn-Yahr were independent risk factors for anxiety disorder in PD patients. After the intervention, the psychological state, cognitive function and quality of life improved in both the CMO and CBT groups, with the CBT group showing better improvement Results from follow-up showed that the number and frequency of falls was lower in the CBT group than in the CMO group, and that patients were more satisfied with the CBT intervention than the CMO group. L-dopa treatment alleviated anxiety in PD mice. L-dopa treatment increased BDNF, p-PI3K, and p-Akt protein levels. Moreover, the combination of L-dopa and CBT enhanced the boosting effect of L-dopa on these proteins.

CONCLUSION

CBT is an effective treatment for anxiety in patients with Parkinson's disease. Medications combined with CBT have been shown to be effective in improving depression, anxiety and quality of life in PDAD patients.

Prevalence of experienced changes in artistic and everyday creativity in people with Parkinson's disease

Creativity is the ability to generate novel and meaningful ideas or behaviors, encompassing both artistic originality and personal satisfaction. Emerging evidence suggests that people with Parkinson's disease (PD) may experience changes in creativity. This study examines the prevalence of creativity changes in PD using cross-sectional data from the Netherlands (PRIME-NL, 2021-2023). Participants (N = 793) self-reported creativity changes, demographics, clinical factors, and pre-diagnosis creative engagement via a self-structured questionnaire. Descriptive analyses revealed that 41% of respondents reported creativity changes: 12% experienced an increase, 22% a decrease, and 7% fluctuations. Ordinal regression analysis showed that longer disease duration and dopamine agonists were associated with increased creativity, while older age and prior creative engagement predicted decreases. A sub-cohort (n = 292) reported creativity changes across seven domains, with changes most frequently observed in everyday creativity, sports/movement, and fine art/design. These findings underscore the need for further research on creativity in PD to inform person-centered treatment strategies.

Behavioral disorders in Parkinson disease: current view

Patients with Parkinson disease (PD) frequently experience several behavioral symptoms, such as anxiety, apathy, irritability, agitation, impulsive control and obsessive-compulsive or REM sleep behavior disorders, which can cause severe psychosocial problems and impair quality of life. Occurring in 30-70% of PD patients, these symptoms can manifest at early stages of the disease, sometimes even before the appearance of classic motor symptoms, while others can develop later. Behavioral changes in PD show distinct patterns of brain atrophy, dopaminergic and serotonergic deterioration, altered neuronal connectivity in frontostriatal, corticolimbic, default mode and other networks due to a cascade linking molecular pathologies and deficits in multiple behavior domains. The changes suggest a multi-system neurodegenerative process in the context of a specific α-synucleinopathy inducing a variety of biochemical and functional changes, the neurobiological basis and clinical relevance of which await further elucidation. This paper is intended to review the recent literature with focus on the main behavioral disturbances in PD patients, their epidemiology, clinical features, risk factors, animal models, neuroimaging findings, pathophysiological backgrounds, and treatment options of these deleterious lesions.

Unleashing creativity in people with Parkinson's disease: a pilot study of a co-designed creative arts therapy

BACKGROUND

Conventional medical management, while essential, cannot address all multifaceted consequences of Parkinson's disease (PD). This pilot study explores the potential of a co-designed creative arts therapy on health-related quality of life, well-being, and pertinent non-motor symptoms.

METHODS

We conducted an exploratory pilot study with a pre-post design using validated questionnaires. Eight individuals with PD participated in the program. The investigated intervention was a 10-week creative arts therapy with weekly 90-120-min sessions, guided by three creative therapists. Participants were allowed to autonomously select from multiple creative media based on their personal preferences. Explored co-primary outcomes included health-related quality of life (PDQ-39), well-being (ICECAP-A), anxiety/depression (HADS), executive functioning (BRIEF-A), resilience/mental flexibility (FIT-60), and self-efficacy (GSES). We used paired sample t tests for pre-post analysis of the co-primary outcomes and Wilcoxon signed-rank tests for PDQ-39 sub-scores. We also included aesthetic responsiveness (AReA) and healthcare consumption (IMCQ adapted for PD) questionnaires reported as descriptive statistics.

RESULTS

The results showed a significant reduction in anxiety and an increase in well-being. We also observed a slight improvement in cognitive functioning. Finally, we noted a reduction in healthcare consumption (fewer visits at neurologists, specialized PD nurses, and allied healthcare professionals).

CONCLUSION

These findings cautiously suggest that our co-designed, multi-media creative arts therapy has the potential to increase well-being and reduce anxiety, while reducing healthcare consumption. These preliminary findings support the need for a larger, randomized controlled trial to explore the therapeutic potential of creative arts therapy in PD care.

Deep Learning-Based Prediction of Freezing of Gait in Parkinson's Disease With the Ensemble Channel Selection Approach

PURPOSE

A debilitating and poorly understood symptom of Parkinson's disease (PD) is freezing of gait (FoG), which increases the risk of falling. Clinical evaluations of FoG, relying on patients' subjective reports and manual examinations by specialists, are unreliable, and most detection methods are influenced by subject-specific factors.

METHOD

To address this, we developed a novel algorithm for detecting FoG events based on movement signals. To enhance efficiency, we propose a novel architecture integrating a bottleneck attention module into a standard bidirectional long short-term memory network (BiLSTM). This architecture, adaptable to a convolution bottleneck attention-BiLSTM (CBA-BiLSTM), classifies signals using data from ankle, leg, and trunk sensors.

FINDING

Given three movement directions from three locations, we reduce computational complexity in two phases: selecting optimal channels through ensemble learning followed by feature reduction using attention mapping. In FoG event detection tests, performance improved significantly compared to control groups and existing methods, achieving 99.88% accuracy with only two channels.

CONCLUSION

The reduced computational complexity enables real-time monitoring. Our approach demonstrates substantial improvements in classification results compared to traditional deep learning methods.

Efficacy of acupuncture in ameliorating anxiety in Parkinson's disease: a systematic review and meta-analysis with trial sequential analysis

Background

Although numerous studies have explored acupuncture for alleviating Parkinson's disease (PD) symptoms, specific methods focusing on reducing anxiety in these patients are lacking. Preliminary research indicates that acupuncture may improve anxiety in patients with Parkinson's; however, high-quality evidence is lacking. Therefore, we conducted a meta-analysis and trial sequential analysis (TSA) to assess the efficacy of acupuncture in managing anxiety symptoms in PD.

Methods

We systematically searched eight databases for randomized controlled trials (RCTs) evaluating the efficacy of acupuncture for the treatment of anxiety in patients with PD. Primary outcomes were measured using the Hamilton Anxiety Scale (HAMA) and the Self-Rating Anxiety Scale (SAS). Secondary outcomes included the Parkinson's Disease Questionnaire-39 (PDQ-39) and the Unified Parkinson's Disease Rating Scale (UPDRS). Risk of bias was assessed using the Cochrane RoB 2.0 tool, and certainty of evidence was assessed using the GRADE system. The Trial Sequential Analysis (TSA) was used to assess the sufficiency of the evidence.

Results

Our meta-analysis included 14 studies. The Manual acupuncture (MA) + routine drug treatment (RDT) group improved more than the RDT alone group. MA was more effective than sham acupuncture. MA+ traditional Chinese medicine (TCM) was also more effective than TCM. Auricular therapy (AT) was not as effective as control therapy (CT). The Electroacupuncture (EA) + routine drug treatment (RDT) group was not as effective as RDT. PDQ-39 and UPDRS subgroup analysis showed that the acupuncture group had better clinical efficacy than CT. The GRADE assessment rated the overall certainty of evidence for anxiety outcomes as low, PDQ-39 as very low and UPDRS as low. TSA results indicate insufficient evidence; further high-quality RCTs are needed to substantiate these findings.

Conclusion

Our analysis suggests that MA combined with RDT may help ameliorate anxiety in PD patients, although the evidence is weak due to low quality RCTs. EA and AT showed no significant effects, highlighting the need for more rigorous studies with better controls and longer follow-up. The potential of acupuncture for PD-related anxiety should be considered with caution until stronger evidence becomes available.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/.

Implications of p53 in mitochondrial dysfunction and Parkinson's disease

Purpose: To study the underlying molecular mechanisms of p53 in the mitochondrial dysfunction and the pathogenesis of Parkinson's disease (PD), and provide a potential therapeutic target for PD treatment.

Methods: We review the contributions of p53 to mitochondrial changes leading to apoptosis and the subsequent degeneration of dopaminergic neurons in PD.

Results: P53 is a multifunctional protein implicated in the regulation of diverse cellular processes via transcription-dependent and transcription-independent mechanisms. Mitochondria are vital subcellular organelles for that maintain cellular function, and mitochondrial defect and impairment are primary causes of dopaminergic neuron degeneration in PD. Increasing evidence has revealed that mitochondrial dysfunction-associated dopaminergic neuron degeneration is tightly regulated by p53 in PD pathogenesis. Neurodegenerative stress triggers p53 activation, which induces mitochondrial changes, including transmembrane permeability, reactive oxygen species production, Ca2+ overload, electron transport chain defects and other dynamic alterations, and these changes contribute to neurodegeneration and are linked closely with PD occurrence and development. P53 inhibition has been shown to attenuate mitochondrial dysfunction and protect dopaminergic neurons from degeneration under conditions of neurodegenerative stress.

Conclusions: p53 appears to be a potential target for neuroprotective therapy of PD.

Neurodegenerative disorders: Mechanisms of degeneration and therapeutic approaches with their clinical relevance

Neurodegenerative disorders (NDs) are expected to pose a significant challenge for both medicine and public health in the upcoming years due to global demographic changes. NDs are mainly represented by degeneration/loss of neurons, which is primarily accountable for severe mental illness. This neuronal degeneration leads to many neuropsychiatric problems and permanent disability in an individual. Moreover, the tight junction of the brain, blood-brain barrier (BBB)has a protective feature, functioning as a biological barrier that can prevent medicines, toxins, and foreign substances from entering the brain. However, delivering any medicinal agent to the brain in NDs (i.e., Multiple sclerosis, Alzheimer's, Parkinson's, etc.) is enormously challenging. There are many approved therapies to address NDs, but most of them only help treat the associated manifestations. The available therapies have failed to control the progression of NDs due to certain factors, i.e., BBB and drug-associated undesirable effects. NDs have extremely complex pathology, with many pathogenic mechanisms involved in the initiation and progression; thereby, a limited survival rate has been observed in ND patients. Hence, understanding the exact mechanism behind NDs is crucial to developing alternative approaches for improving ND patients' survival rates. Thus, the present review sheds light on different cellular mechanisms involved in NDs and novel therapeutic approaches with their clinical relevance, which will assist researchers in developing alternate strategies to address the limitations of conventional ND therapies. The current work offers the scope into the near future to improve the therapeutic approach of NDs.

Parkinson's disease with anxiety: clinical characteristics and their correlation with oxidative stress, inflammation, and pathological proteins

OBJECTIVE

This study was performed to explore the differences in the clinical characteristics and oxidative stress indicators, inflammatory factors, and pathological proteins in serum between Parkinson's disease (PD) with anxiety (PD-A) and with no anxiety (PD-NA) patients, and further correlations among clinical characteristics and above variables were analyzed in PD-A and PD-NA groups.

METHODS

A total of 121 patients with PD were enrolled in this study and assessed by the Hamilton Anxiety Scale (14 items) (HAMA-14). These patients were divided into PD-A and PD-NA groups according to a cut-off point of 7 of HAMA-14. Demographic variables were collected, and clinical symptoms were assessed by multiple rating scales. The levels of free radicals, inflammatory factors, and pathological proteins in serum were measured by chemical colorimetric method and enzyme-linked immunosorbent assay (ELISA). The differences of above variables were compared between PD-A and PD-NA groups, and the correlations of clinical symptoms with the abovevariables were analyzed in PD-A and PD-NA groups.

RESULTS

The frequency of PD-A was 62.81%. PD-A group exhibited significantly impaired motor dysfunction and multiple non-motor symptoms, including fatigue, sleep behavior disorder, restless leg syndrome and autonomic dysfunction, and dramatically compromised activities of daily living compard with PD-NA group. PD-A group displayed prominently increasedlevels of hydroxyl radical (·OH) and tumor necrosis factor (TNF)-α, and a decreased nitric oxide (NO) level in serum compared with PD-NA group (P<0.001, P = 0.001, P= 0.027, respectively). ·OH, NO, and TNF-α were identified as the risk factors of PD-A (OR = 1.005, P = 0.036; OR = 0.956, P = 0.017; OR = 1.039, P = 0.033, respectively). In PD patients, HAMA-14 score was significantly and positively correlated with the levels of ·OH and TNF-α in serum (P<0.001, P = 0.002, respectively). In PD-A group, ·OH level was significantly and negatively correlated with Aβ1-42 level, while TNF-α level was significantly and positively correlated with P-tau (S396) level in serum.

CONCLUSIONS

The frequency of PD-A is high. PD-A patients present more severe motor dysfunction and multiple non-motor symptoms, and poorer activities of daily living. The increased levels of ·OH and TNF-α levels and the decreased NO level in serum are all associated with more severe anxiety in PD patients.Findings from this study may provide in-depth insights into the clinical characteristics, underlying mechanisms of PD-A, and potential correlations among anxiety, oxidative stress, inflammation, and cognitive decline in PD patients.

The avBNSTGABA-VTA and avBNSTGABA-DRN pathways are respectively involved in the regulation of anxiety-like behaviors in parkinsonian rats

The anteroventral bed nucleus of stria terminalis (avBNST) is a key brain region which involves negative emotional states, such as anxiety. The most neurons in the avBNST are GABAergic, and it sends GABAergic projections to the ventral tegmental area (VTA) and the dorsal raphe nucleus (DRN), respectively. The VTA and DRN contain dopaminergic and serotonergic cell groups in the midbrain which regulate anxiety-like behaviors. However, it is unclear the role of GABAergic projections from the avBNST to the VTA and the DRN in the regulation of anxiety-like behaviors, particularly in Parkinson's disease (PD)-related anxiety. In the present study, unilateral 6-hydroxydopamine (6-OHDA) lesions of the substantia nigra pars compacta in rats induced anxiety-like behaviors, and decreased level of dopamine (DA) in the basolateral amygdala (BLA). Chemogenetic activation of avBNSTGABA-VTA or avBNSTGABA-DRN pathway induced anxiety-like behaviors and decreased DA or 5-HT release in the BLA in sham and 6-OHDA rats, while inhibition of avBNSTGABA-VTA or avBNSTGABA-DRN pathway produced anxiolytic-like effects and increased level of DA or 5-HT in the BLA. These findings suggest that avBNST inhibitory projections directly regulate dopaminergic neurons in the VTA and serotonergic neurons in the DRN, and the avBNSTGABA-VTA and avBNSTGABA-DRN pathways respectively exert impacts on PD-related anxiety-like behaviors.

Locus coeruleus injury modulates ventral midbrain neuroinflammation during DSS-induced colitis

Parkinson's disease (PD) is characterized by a decades-long prodrome, consisting of a collection of non-motor symptoms that emerges prior to the motor manifestation of the disease. Of these non-motor symptoms, gastrointestinal dysfunction and deficits attributed to central norepinephrine (NE) loss, including mood changes and sleep disturbances, are frequent in the PD population and emerge early in the disease. Evidence is mounting that injury and inflammation in the gut and locus coeruleus (LC), respectively, underlie these symptoms, and the injury of these systems is central to the progression of PD. In this study, we generate a novel two-hit mouse model that captures both features, using dextran sulfate sodium (DSS) to induce gut inflammation and N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) to lesion the LC. We first confirmed the specificity of DSP-4 for central NE using neurochemical methods and fluorescence light-sheet microscopy of cleared tissue, and established that DSS-induced outcomes in the periphery, including weight loss, gross indices of gut injury and systemic inflammation, the loss of tight junction proteins in the colonic epithelium, and markers of colonic inflammation, were unaffected with DSP-4 pre-administration. We then measured alterations in neuroimmune gene expression in the ventral midbrain in response to DSS treatment alone as well as the extent to which prior LC injury modified this response. In this two-hit model we observed that DSS-induced colitis activates the expression of key cytokines and chemokines in the ventral midbrain only in the presence of LC injury and the typical DSS-associated neuroimmune is blunted by pre-LC lesioning with DSP-4. In all, this study supports the growing appreciation for the LC as neuroprotective against inflammation-induced brain injury and draws attention to the potential for NEergic interventions to exert disease-modifying effects under conditions where peripheral inflammation may compromise ventral midbrain dopaminergic neurons and increase the risk for development of PD.

Effect of Rhythmically Cued Exercise Interventions on Functions in Patients With Parkinson Disease: A Meta-Analysis

OBJECTIVE

The purpose of this review was to investigate the efficacy of rhythmically cued exercise interventions on motor function, cognition, and mental state in patients with Parkinson disease.

METHODS

PubMed, Cochrane Database, Web of Science, Embase, and CINAHL were searched June 15, 2023. Original studies investigating the efficacy of rhythmically cued exercise interventions on the functions of patients with Parkinson disease were included. The Cochrane risk-of-bias assessment tool was used to evaluate the risk of bias. The protocol was registered in PROSPERO (CRD42022371203).

RESULTS

A total of 38 original studies involving 1486 participants were included. Rhythmically cued exercise interventions demonstrated superior effects on motor function compared to exercise therapy without rhythm (standardized mean difference [SMD] = -0.31). However, no significant improvements were observed in cognition and mental state. Overall, significant improvements were observed in motor examination (SMD = -0.61), Timed "Up & Go" Test (mean difference [MD] = -0.91), activities of daily living (SMD = -0.49), balance (SMD = 0.59), walking velocity (MD = 0.06), step length (MD = 2.65), and stride length (MD = 0.04) following rhythmically cued exercise interventions. No significant improvements were observed in freezing of gait and cadence. Assessment of publication bias showed no significant evidence of publication bias. Meta-regression analyses revealed a significant association between treatment duration and improvement in motor function. Furthermore, adverse events and dropout rates did not significantly differ between the 2 groups.

CONCLUSION

Rhythmically cued exercise interventions are effective in improving motor function in the early to middle stages of Parkinson disease. More than 10 weeks of intervention yielded better results. However, these interventions do not have a significant impact on cognition and mental states. Importantly, rhythmically cued exercise interventions are safe and well tolerated. Large-scale trials are needed for further confirmation.

IMPACT

This study contributes to the development of safe and reliable home rehabilitation programs, aiming to enhance the quality of life for patients with Parkinson disease.

Aqueous extract of Swietenia macrophylla leaf exerts an anti-inflammatory effect in a murine model of Parkinson's disease induced by 6-OHDA

Introduction

Parkinson's disease affects 2% of the population aged over 65 years and is the second most common neurodegenerative disorder in the general population. The appearance of motor symptoms is associated with the degeneration of dopaminergic neurons in the nigrostriatal pathway. Clinically significant nonmotor symptoms are also important for severe disability with disease progression. Pharmacological treatment with levodopa, which involves dopamine restitution, results in a temporary improvement in motor symptoms. Among the mechanisms underlying the pathogenesis of the disease are exacerbated oxidative stress, mitochondrial dysfunction, and neuroinflammation. A phytochemical prospecting study showed that the aqueous extract of the leaves from Swietenia macrophylla (Melineaceae), known as mahogany, has polyphenols with antioxidant and anti-inflammatory capacity in a significantly higher percentage than leaf extracts from other Amazonian plants. Furthermore, the antioxidant and anti-inflammatory capacity of aqueous extract of mahogany leaf has already been demonstrated in an in vitro model. In this study, we hypothesized that the aqueous extract of mahogany leaf (AEML) has a neuroprotective effect in a murine model of Parkinson's disease induced by 6-hydroxidopamine (6-OHDA), due to antioxidant and anti-inflammatory properties of its phenolic compounds.

Methods

Mice were treated daily with the mahogany extract at a dose of 50 mg/kg, starting 7 days before 6-OHDA infusion until post-surgery day 7.

Results and discussion

The animals from the 6-OHDA/mahogany group, which corresponds to animals injected with the toxin and treated with aqueous extract of the mahogany leaf, presented distinct behavioral phenotypes after apomorphine challenge and were therefore subdivided into 2 groups, 6-OHDA/mahogany F1 and 6-OHDA/mahogany F2. The F1 group showed a significant increase in contralateral rotations, whereas the F2 group did not show rotations after the apomorphine stimulus. In the F1 group, there was an increase, although not significant, in motor performance in the open field and elevated plus maze tests, whereas in the F2 group, there was significant improvement, which may be related to the lesser degree of injury to the nigrostriatal dopaminergic pathway. The TH+ histopathological analysis, a dopaminergic neuron marker, confirmed that the lesion to the nigrostriatal dopaminergic pathway was more pronounced in 6-OHDA/mahogany F1 than in 6-OHDA/mahogany F2. Our main result consisted of signs of improvement in the inflammatory profile in both the F1 and F2 6-OHDA/mahogany groups, such as a lower number of IBA-1+ microglial cells in the ventral striatum and substantia nigra pars compacta and a reduction in GFAP+ expression, an astrocyte marker, in the dorsal striatum. In this study, several bioactive compounds in the aqueous extract of mahogany leaf may have contributed to the observed beneficial effects. Further studies are necessary to better characterize their applicability for treating chronic degenerative diseases with inflammatory and oxidative bases, such as Parkinson's disease.

Locus coeruleus injury modulates ventral midbrain neuroinflammation during DSS-induced colitis

Parkinson's disease (PD) is characterized by a decades-long prodrome, consisting of a collection of non-motor symptoms that emerges prior to the motor manifestation of the disease. Of these non-motor symptoms, gastrointestinal dysfunction and deficits attributed to central norepinephrine (NE) loss, including mood changes and sleep disturbances, are frequent in the PD population and emerge early in the disease. Evidence is mounting that injury and inflammation in the gut and locus coeruleus (LC), respectively, underlie these symptoms, and the injury of these systems is central to the progression of PD. In this study, we generate a novel two-hit mouse model that captures both features, using dextran sulfate sodium (DSS) to induce gut inflammation and N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) to lesion the LC. We first confirmed the specificity of DSP-4 for central NE using neurochemical methods and fluorescence light-sheet microscopy of cleared tissue, and established that DSS-induced outcomes in the periphery, including weight loss, gross indices of gut injury and systemic inflammation, the loss of tight junction proteins in the colonic epithelium, and markers of colonic inflammation, were unaffected with DSP-4 pre-administration. We then measured alterations in neuroimmune gene expression in the ventral midbrain in response to DSS treatment alone as well as the extent to which prior LC injury modified this response. In this two-hit model we observed that DSS-induced colitis activates the expression of key cytokines and chemokines in the ventral midbrain only in the presence of LC injury and the typical DSS-associated neuroimmune is blunted by pre-LC lesioning with DSP-4. In all, this study supports the growing appreciation for the LC as neuroprotective against inflammation-induced brain injury and draws attention to the potential for NEergic interventions to exert disease-modifying effects under conditions where peripheral inflammation may compromise ventral midbrain dopaminergic neurons and increase the risk for development of PD.

A general clinical overview of the non-motor symptoms in Parkinson's disease: Neuropsychiatric symptoms

The heterogeneity of non-motor features observed in people with Parkinson's disease (PD) is often dominated by one or more symptoms belonging to the neuropsychiatric spectrum, such as cognitive impairment, psychosis, depression, anxiety, and apathy. Due to their high prevalence in people with PD (PwP) and their occurrence in every stage of the disease, from the prodromal to the advanced stage, it is not surprising that PD can be conceptualised as a complex neuropsychiatric disorder. Despite progress in understanding the pathophysiological mechanisms underlying the neuropsychiatric signs and symptoms in PD, and better identification and diagnosis of these symptoms, effective treatments are still a major unmet need. The impact of these symptoms on the quality of life of PwP and caregivers, as well as their contribution to the overall non-motor symptom burden can be greater than that of motor symptoms and require a personalised, holistic approach. In this chapter, we provide a general clinical overview of the major neuropsychiatric symptoms of PD.

Investigating In silico and In vitro Therapeutic Potential of Diosmetin as the Anti-Parkinson Agent

AIM

This study aimed to investigate how diosmetin interacts with seven target receptors associated with oxidative stress (OS) and validate its antioxidant properties for the potential management of Parkinson's disease (PD).

BACKGROUND

In PD, the degeneration of dopaminergic cells is strongly influenced by OS. This stressor is intricately connected to various mechanisms involved in neurodegeneration, such as mitochondrial dysfunction, neuroinflammation, and excitotoxicity induced by nitric oxide.

OBJECTIVE

The aim of this research was to establish a molecular connection between diosmetin and OS-associated target receptors was the goal, and it investigated how this interaction can lessen PD.

METHODS

Seven molecular targets - Adenosine A2A (AA2A), Peroxisome Proliferator-Activated Receptor Gamma (PPARγ), Protein Kinase AKT1, Nucleolar Receptor NURR1, Liver - X Receptor Beta (LXRβ), Monoamine Oxidase - B (MAO-B) and Tropomyosin receptor kinase B (TrkB) were obtained from RCSB. Molecular docking software was employed to determine molecular interactions, while antioxidant activity was assessed through in vitro assays against various free radicals.

RESULTS

Diosmetin exhibited interactions with all seven target receptors at their binding sites. Notably, it showed superior interaction with AA2A and NURR1 compared to native ligands, with binding energies of -7.55, and -6.34 kcal/mol, respectively. Additionally, significant interactions were observed with PPARγ, AKT1, LXRβ, MAO-B, and TrkB with binding energies of -8.34, -5.42, -7.66, -8.82, -8.45 kcal/mol, respectively. Diosmetin also demonstrated antioxidant activity against various free radicals, particularly against hypochlorous acid (HOCl) and nitric oxide (NO) free radicals.

CONCLUSION

Diosmetin possibly acts on several target receptors linked to the pathophysiology of PD, demonstrating promise as an OS inhibitor and scavenger.

Effect of dopamine on limbic network connectivity at rest in Parkinson's disease patients with freezing of gait

Background

Freezing of gait (FOG) in Parkinson's disease (PD) has a poorly understood pathophysiology, which hinders treatment development. Recent work showed a dysfunctional fronto-striato-limbic circuitry at rest in PD freezers compared to non-freezers in the dopamine "OFF" state. While other studies found that dopaminergic replacement therapy alters functional brain organization in PD, the specific effect of dopamine medication on fronto-striato-limbic functional connectivity in freezers remains unclear.

Objective

To evaluate how dopamine therapy alters resting state functional connectivity (rsFC) of the fronto-striato-limbic circuitry in PD freezers, and whether the degree of connectivity change is related to freezing severity and anxiety.

Methods

Twenty-three PD FOG patients underwent MRI at rest (rsfMRI) in their clinically defined "OFF" and "ON" dopaminergic medication states. A seed-to-seed based analysis was performed between a priori defined limbic circuitry ROIs. Functional connectivity was compared between OFF and ON states. A secondary correlation analyses evaluated the relationship between Hospital Anxiety and Depression Scale (HADS)-Anxiety) and FOG Questionnaire with changes in rsFC from OFF to ON.

Results

PD freezers' OFF compared to ON showed increased functional coupling between the right hippocampus and right caudate nucleus, and between the left putamen and left posterior parietal cortex (PPC). A negative association was found between HADS-Anxiety and the rsFC change from OFF to ON between the left amygdala and left prefrontal cortex, and left putamen and left PPC.

Conclusion

These findings suggest that dopaminergic medication partially modulates the frontoparietal-limbic-striatal circuitry in PD freezers, and that the influence of medication on the amygdala, may be related to clinical anxiety in freezer.

Anxiety in Parkinson's Patients: What's Timing Got to Do with It?

Background: Parkinson's Disease (PD) affects over 10 million people worldwide. Many PD patients experience comorbid anxiety disorders, which have been correlated with reduced quality of life and can manifest at any time during the course of PD, including prior to motor symptom onset. Purpose: Prior work has demonstrated that patients diagnosed with depression following a PD diagnosis are less likely to receive depression treatment, but no such study has been conducted for anxiety. Research Design: A cross-sectional analysis of secondary electronhic health record data was conducted. Study Sample: Data was obtained through Optum® de-identified Electronic Health Record dataset, using ICD-9 and ICD-10 diagnosis codes to determine PD status and comparing index date of anxiety and PD diagnoses to classify patients by relative time of diagnosis. Data Analysis: Multivariate logistic regression was performed to assess factors associated with receipt of mental health treatment. Results: Of PD patients with anxiety, 52% documented a diagnosis of anxiety prior to PD. Overall, 69% documented some treatment, with 79% of those diagnosed with anxiety prior to PD receiving some treatment compared to 59% of those diagnosed with anxiety on or after PD (P < 0.001). Conclusion: Patients with PD and subsequent anxiety diagnoses are less likely to receive treatment. Further study could explore reasons for variations in mental health care within the context of an existing PD diagnosis.

Premature drug reduction after subthalamic nucleus deep brain stimulation leading to worse depression in patients with Parkinson's disease

Background

Reduction of medication in Parkinson's disease (PD) following subthalamic nucleus deep brain stimulation (STN-DBS) has been recognized, but the optimal timing for medication adjustments remains unclear, posing challenges in postoperative patient management.

Objective

This study aimed to provide evidence for the timing of medication reduction post-DBS using propensity score matching (PSM).

Methods

In this study, initial programming and observation sessions were conducted over 1 week for patients 4-6 weeks postoperatively. Patients were subsequently categorized into medication reduction or non-reduction groups based on their dyskinesia evaluation using the 4.2-item score from the MDS-UPDRS-IV. PSM was employed to maintain baseline comparability. Short-term motor and neuropsychiatric symptom assessments for both groups were conducted 3-6 months postoperatively.

Results

A total of 123 PD patients were included. Baseline balance in motor and non-motor scores was achieved between the two groups based on PSM. Short-term efficacy revealed a significant reduction in depression scores within the non-reduction group compared to baseline (P < 0.001) and a significant reduction compared to the reduction group (P = 0.037). No significant differences were observed in UPDRS-III and HAMA scores between the two groups. Within-group analysis showed improvements in motor symptoms, depression, anxiety, and subdomains in the non-reduction group, while the reduction group exhibited improvements only in motor symptoms.

Conclusion

This study provides evidence for the timing of medication reduction following DBS. Our findings suggest that early maintenance of medication stability is more favorable for improving neuropsychiatric symptoms.

Serotonin and dopamine depletion in distinct brain regions may cause anxiety in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice as a model of early Parkinson's disease

In this study, we aimed to evaluate the association of early anxious behavior with serotonin, dopamine, and their metabolites in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) murine model of Parkinson's disease. Forty C57BL/6 male mice were randomly divided into the control group (n = 20) and the model group (n = 20). Mice in the model group were injected intraperitoneally with MPTP. The light-dark box (LDB) and elevated plus-maze were used to monitor anxious behavior. The association of early anxious behavior with neurotransmitters in the prefrontal cortex, hippocampus, and striatum was evaluated. In our murine model, MPTP induced a decreased level of 5-hydroxytryptamine and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the prefrontal cortex, hippocampus, and striatum (all P < 0.05); however, it only induced a decreased level of dopamine and its metabolite homovanillic acid (HVA) in the striatum (both P < 0.001), with a negative correlation in the hippocampus and a positive correlation in the cortex and striatum. In the LDB, 5-hydroxytryptamine levels in the cortex and dopamine and HVA levels in the striatum were negatively correlated with anxious behavior. Moreover, in the elevate plus-maze, 5-hydroxytryptamine and 5-HIAA in the cortex and dopamine and HVA in the striatum were positively correlated with the ratio of the time spent in open arms. In the murine model of early Parkinson's disease, the balance between dopamine and 5-hydroxytryptamine systems varied among brain regions. The depletion of 5-hydroxytryptamine in the cortex and dopamine in the striatum may be associated with anxiety behaviors in MPTP-treated mice.

The α1 and γ2 subunit-containing GABAA receptor-mediated inhibitory transmission in the anteroventral bed nucleus of stria terminalis is involved in the regulation of anxiety in rats with substantia nigra lesions

The anteroventral bed nucleus of the stria terminalis (avBNST) is widely acknowledged as a key brain structure that regulates negative emotional states, such as anxiety. At present, it is still unclear whether GABA_A receptor-mediated inhibitory transmission in the avBNST is involved in Parkinson's disease (PD)-related anxiety. In this study, unilateral 6-hydroxydopamine (6-OHDA) lesions of the substantia nigra pars compacta (SNc) in rats induced anxiety-like behaviors, increased GABA synthesis and release, and upregulated expression of GABA_A receptor subunits in the avBNST, as well as decreased level of dopamine (DA) in the basolateral amygdala (BLA). In both sham and 6-OHDA rats, intra-avBNST injection of GABA_A receptor agonist muscimol induced the following changes: (i) anxiolytic-like responses, (ii) inhibition of the firing activity of GABAergic neurons in the avBNST, (iii) excitation of dopaminergic neurons in the ventral tegmental area (VTA) and serotonergic neurons in the dorsal raphe nucleus (DRN), and (iv) increase of DA and 5-HT release in the BLA, whereas antagonist bicuculline induced the opposite effects. Collectively, these findings suggest that degeneration of the nigrostriatal pathway enhances GABA_A receptor-mediated inhibitory transmission in the avBNST, which is involved in PD-related anxiety. Further, activation and blockade of avBNST GABA_A receptors affect the firing activity of VTA dopaminergic and DRN serotonergic neurons, and then change release of BLA DA and 5-HT, thereby regulating anxiety-like behaviors.

Parkinson's Disease Related Depression and Anxiety: A 22-Year Bibliometric Analysis (2000-2022)

Background

Parkinson's disease (PD) is one of the common neurodegenerative diseases. Depression and anxiety are the most common psychiatric symptoms of PD. It is important to study the potential relationship between PD and depression or anxiety.

Aim

This study aimed to use bibliometrics to analyze the papers about parkinson's disease related depression and anxiety over the last 22 years, and to characterize the current status of research and predict future hotspots.

Methods

In the Web of Science Core Collection (WoSCC) from 2000 to 2022, documents are searched according to specific subject words. The selected literature was retrospectively analyzed and mapped using CiteSpace and Vosviewer software. We analyzed countries, institutions, journals, authors, references and keywords.

Results

A total of 7368 papers were included from 2000 to 2022, and the number of publications has shown an upward trend year by year. Movement Disorder is the journal with the highest number of publications (391 publications, 5.31%) and citations (30,549 times), with the United States (2055 publications, 27.9%) and the University of Toronto (158 publications) being the countries and institutions with the highest number of publications. The high-frequency keywords focused on "quality of life", "deep brain stimulation" and "non-motor symptoms". "Functional connectivity", "gut microbiota" and "inflammation" may be at the forefront of future research.

Conclusion

Parkinson's disease related depression and anxiety have been increasingly studied over the past 22 years. Functional connectivity, gut microbiota, and inflammation will be the subject of active research hotspots in the future, and these findings may provide new research ideas for researchers.

Dimethyl fumarate ameliorates Parkinsonian pathology by modulating autophagy and apoptosis via Nrf2-TIGAR-LAMP2/Cathepsin D axis

Mounting evidence suggests a role for oxidative stress and accumulation of dysfunctional organelle and misfolded proteins in PD. Autophagosomes mediate the clearance of these cytoplasmic proteins via delivery to lysosomes to form autophagolysosomes, followed by degradation of the protein by lysosomal enzymes. In PD, autophagolysosome accumulation occurs initiating a plethora of events resulting in neuronal death by apoptosis. This study evaluated the effect of Dimethylfumarate (DMF), an Nrf2 activator in the rotenone-induced mouse PD model. In PD mice, there was decreased expression of LAMP2 and LC3, which resulted in inhibition of autophagic flux and increased expression of cathepsin D, which mediated apoptosis. The role of Nrf2 activation in alleviating oxidative stress is well known. Our study elucidated the novel mechanism underlying the neuroprotective effect of DMF. The loss of dopaminergic neurons induced by rotenone was lessened to a significant extent by pre-treatment with DMF. DMF promoted autophagosome formation and inhibited apoptosis by removing the inhibitory effect of p53 on TIGAR. TIGAR expression upregulated LAMP2 expression and downregulated Cathepsin D, promoting autophagy and inhibiting apoptosis. Thus, it was proved that DMF confers neuroprotection against rotenone-induced dopaminergic neurodegeneration and could be used as a potential therapeutic agent for PD and its progression.

Art therapy as a comprehensive complementary treatment for Parkinson's disease

Introduction

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. Complementary and alternative therapies are increasingly utilized to address its complex multisystem symptomatology. Art therapy involves motoric action and visuospatial processing while promoting broad biopsychosocial wellness. The process involves hedonic absorption, which provides an escape from otherwise persistent and cumulative PD symptoms, refreshing internal resources. It involves the expression in nonverbal form of multilayered psychological and somatic phenomena; once these are externalized in a symbolic arts medium, they can be explored, understood, integrated, and reorganized through verbal dialogue, effecting relief and positive change.

Methods

42 participants with mild to moderate PD were treated with 20 sessions of group art therapy. They were assessed before and after therapy with a novel arts-based instrument developed to match the treatment modality for maximum sensitivity. The House-Tree-Person PD Scale (HTP-PDS) assesses motoric and visuospatial processing-core PD symptoms-as well as cognition (thought and logic), affect/mood, motivation, self (including body-image, self-image, and self- efficacy), interpersonal functioning, creativity, and overall level of functioning. It was hypothesized that art therapy will ameliorate core PD symptoms and that this will correlate with improvements in all other variables.

Results

HTP-PDS scores across all symptoms and variables improved significantly, though causality among variables was indeterminate.

Discussion

Art therapy is a clinically efficacious complementary treatment for PD. Further research is warranted to disentangle causal pathways among the aforementioned variables, and additionally, to isolate and examine the multiple, discrete healing mechanisms believed to operate simultaneously in art therapy.

The effect of physical exercise on anxiety in people with parkinson’s disease: A systematic review of randomized control trials

BACKGROUND Anxiety is a prominent disabling non-motor neuropsychiatric complication of Parkinson’s disease (PD). Pharmacological treatments for PD and anxiety have drug interactions and negative side effects. Therefore, non-pharmacological interventions such as exercise has been proposed to reduce anxiety in people with PD (PwP). OBJECTIVE This systematic review aimed to explore the relationship between physical exercise and anxiety in PwP. METHOD Four databases (PubMed, Embase, Scopus, Ebscohost) were searched without date restrictions. English randomized control trials (RCT) including adults with PD, exposed to physical exercise interventions with anxiety as an outcome variable, were included. Quality was assessed by means of an adapted 9-point PEDro scale. RESULTS Five of the identified 5547 studies met the inclusion criteria. Sample size ranged between 11–152 participants, totaling 328 participants with majority being male. PD stage ranged from early to moderate, with disease duration ranged between 2.9 and 8.0 years. All studies measured anxiety at baseline and post-intervention. On average studies scored 7/9 (76%) on the PEDro scale. CONCLUSION There is insufficient evidence to support or refute the effect of exercise on anxiety in PwP due to noted limitations of included studies. There is an urgent need for high-quality RCTs on physical exercise and anxiety in PwP.

Longitudinal cognitive changes in patients with early Parkinson's disease and neuropsychiatric symptoms

AIMS

In this study, we aimed to investigate the effect of neuropsychiatric symptoms (NPS) on the rate of cognitive decline for both global cognition and specific cognitive domains in a cohort of patients from the Parkinson's Progression Markers Initiative (PPMI).

METHOD

Prospectively longitudinal data were obtained from the PPMI cohort. NPS, including depression, anxiety, apathy, psychosis, impulse control disorders (ICDs), and cognition ability, were evaluated by a series of questionnaires. Linear mixed-effects models were used to investigate the relationship between NPS and the rate of cognitive decline. Generalized estimating equations (GEEs) were used to investigate the relationship between NPS and the occurrence of mild cognitive impairment (MCI).

RESULTS

In total, 423 patients with Parkinson's disease (PD) were recruited at baseline and 395, 378, 366, 346, and 315 participants were followed up at 1, 2, 3, 4, and 5 years, respectively. Depression, anxiety, apathy, and psychosis were associated with global cognitive decline. Except for those with ICDs, patients with psychosis, depression, anxiety, and apathy were more likely to meet the criteria for MCI. Patients with depression and anxiety showed a progressive decline in four major cognitive domains. Apathy and ICDs were separately associated with a progressive decline in processing speed-attention and memory, respectively.

CONCLUSIONS

Neuropsychiatric symptoms, including psychosis, depression, anxiety, and apathy, could be used to predict future cognitive decline in patients with PD.

Amygdalo-nigral circuit mediates stress-induced vulnerability to the parkinsonian toxin MPTP

AIMS

The aim was to investigate the effect of mood disorders on parkinsonian toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced motor disability, substantia nigra pars compacta (SNc) dopaminergic (DA) neurons loss. Also, the neural circuit mechanism was elucidated.

METHODS

The depression-like (physical stress, PS) and anxiety-like (emotional stress, ES) mouse models were established by the three-chamber social defeat stress (SDS). The features of Parkinson's disease were reproduced by MPTP injection. Viral-based whole-brain mapping was utilized to resolve the stress-induced global changes in direct inputs onto SNc DA neurons. Calcium imaging and chemogenetic techniques were applied to verify the function of the related neural pathway.

RESULTS

We found that PS mice, but not ES mice, showed worse movement performance and more SNc DA neuronal loss than control mice after MPTP administration. The projection from the central amygdala (CeA) to the SNc^DA was significantly increased in PS mice. The activity of SNc-projected CeA neurons was enhanced in PS mice. Activating or inhibiting the CeA-SNc^DA pathway could mimic or block PS-induced vulnerability to MPTP.

CONCLUSIONS

These results indicated that projections from CeA to SNc DA neurons contribute to SDS-induced vulnerability to MPTP in mice.

Neurobiology of depression in Parkinson's disease: Insights into epidemiology, molecular mechanisms and treatment strategies

Parkinson's disease (PD) is characterized mainly by motor dysfunctions due to the progressive loss of dopaminergic neurons. However, PD patients experience a multitude of debilitating non-motor symptoms, including depression, which may have deleteriously detrimental effects on life. Depression is multifactorial and exhibits a bimodal progression in PD, but its underlying molecular mechanisms are poorly understood. Studies demonstrating the pathophysiology of depression in PD and the specific treatment strategies for depression-like symptoms in PD patients are largely lacking, often underrated, under-recognized and, consequently, inadequately/under-treated. Nevertheless, reports suggest that the incidence of depression is approximately 20-30% of PD patients and may precede the onset of motor symptoms. Diagnosing depression in PD becomes difficult due to the clinical overlap in symptomatology between the two diseases, and the nigrostriatal dysfunction alone is insufficient to explain depressive symptoms in PD. Therefore, the current study provides an overview of the molecular mechanisms underlying the development of depression in PD and new insights into developing current antidepressant strategies to treat depression in PD. This review will identify and understand the molecular pathological mechanisms of depression in PD that will fundamentally help tailoring therapeutic interventions for depressive symptoms in PD.

Benzodiazepine-Receptor Agonist Utilization in Outpatients with Anxiety Disorder: A Retrospective Study Based on Electronic Healthcare Data from a Large General Tertiary Hospital

Benzodiazepine-receptor agonists (BZRAs), including benzodiazepines (BZDs) and drugs related to BZDs (Z-drugs), are commonly used for anxiety, but often have side effects. We retrospectively investigated the utilization and prescription characteristics of BZRAs for patients with anxiety disorders in a large tertiary care general hospital between 2018 and 2021, based on electronic healthcare records. We also examined the pattern of simultaneous consumption of multiple BZRA drugs, and the diseases coexisting with anxiety that are associated with this. The numbers of patients and BZRA prescriptions increased over the 4 years. Moreover, 7195 prescriptions from 694 patients contained two or more BZRAs, of which 78.08% contained both BZDs and Z-drugs, 19.78% contained multiple BZDs, and 2.14% contained multiple Z-drugs. For anxiety patients with concomitant Alzheimer's disease or Parkinson's disease, and dyslipidemia, they were more likely to consume multiple BZRAs simultaneously, whereas patients with concomitant insomnia, depression, hypertension, diabetes, or tumors were less likely to consume multiple BZRAs (all p < 0.05). Furthermore, older patients who consume multiple BZRAs simultaneously may have higher probabilities of long-term drug use. Better interventions supporting standardized BZD utilization may be needed to minimize the side effects of inappropriate BZRA administration.

The psychometric properties of the Chinese version of the Parkinson Anxiety Scale (C-PAS) among Parkinson's disease

BACKGROUND

Anxiety disorder is a common non-motor symptom among individuals with Parkinson's disease (PD). At present, there are no specific tools in China for assessing the anxiety level of patients with PD. This study aimed to test the reliability and validity of the Chinese version of the Parkinson Anxiety Scale (C-PAS) in Chinese patients with PD.

METHODS

A total of 158 patients with PD at one hospital in Nanjing were recruited through convenience sampling. The C-PAS was translated into Chinese using a classic 'forward-backward' translation method. Reliability tests included internal consistency and test-reliability. And in addition to content, structure and criterion-related validity were performed for the validity tests. Criterion-related validity was evaluated with the Hospital Anxiety and Depression Scale-Anxiety Subscale (HADS-A).

RESULTS

Results confirmed the three-factor structure of the original C-PAS with 12 items, including persistent anxiety (5 items), episodic anxiety (4 items) and avoidance behavior (3 items). Significant and positive correlations were obtained between C-PAS and HADS-A (r = 0.82, P<0.01). The Cronbach's α and test-retest reliability of the total scale were 0.89 and 0.84, respectively.

CONCLUSION

The C-PAS has demonstrated good psychometric properties. Therefore, it can be employed in patients with PD to evaluate the condition of anxiety.

Development and Validation of a Prediction Model for Anxiety Improvement after Deep Brain Stimulation for Parkinson Disease

BACKGROUND

Parkinson's disease (PD) represents one of the most frequently seen neurodegenerative disorders, while anxiety accounts for its non-motor symptom (NMS), and it has greatly affected the life quality of PD cases. Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) can effectively treat PD. This study aimed to develop a clinical prediction model for the anxiety improvement rate achieved in PD patients receiving STN-DBS.

METHODS

The present work retrospectively enrolled 103 PD cases undergoing STN-DBS. Patients were followed up for 1 year after surgery to analyze the improvement in HAMA scores. Univariate and multivariate logistic regression were conducted to select factors affecting the Hamilton Anxiety Scale (HAMA) improvement. A nomogram was established to predict the likelihood of achieving anxiety improvement. Receiver operating characteristic (ROC) curve analysis, decision curve analysis (DCA), and calibration curve analysis were conducted to verify nomogram performance.

RESULTS

The mean improvement in HAMA score was 23.9% in 103 patients; among them, 68.9% had improved anxiety, 25.2% had worsened (Preop) anxiety, and 5.8% had no significant change in anxiety. Education years, UPDRS-III preoperative score, and HAMA preoperative score were independent risk factors for anxiety improvement. The nomogram-predicted values were consistent with real probabilities.

CONCLUSIONS

Collectively, a nomogram is built in the present work for predicting anxiety improvement probability in PD patients 1 year after STN-DBS. The model is valuable for determining expected anxiety improvement in PD patients undergoing STN-DBS.

Development and characterization of gastro-floating sustained-release capsule with improved bioavailability of levodopa

In this study, a new gastro-floating sustained-release capsule (GFC) with levodopa (LD) and benserazide hydrochloride (BH) was successfully developed. GFCs were prepared by filling the LD and BH granules into hard capsules and coated with cellulose acetate (CA) solution as a controlled-release layer. The effects of formulation factors on the release of GFCs were conducted. The AUC_0~24 (µg h/mL) of LD were 69.31 ± 3.61 (μg h/mL) and 28.87 ± 2.58 (μg h/mL) and the C_max were 7.84 ± 0.34 (μg/mL) and 9.21 ± 1.04 (μg/mL) in the GFCs and commercial tablets respectively. The relative bioavailability of LD was 267.55 ± 34.54%. Compared with commercial tablets, the pharmacokinetic study indicated that the developed GFCs provided a better sustained-release effect and higher bioavailability than commercial tablets.

Neuroprotective Effect of Phloretin in Rotenone-Induced Mice Model of Parkinson's Disease: Modulating mTOR-NRF2-p62 Mediated Autophagy-Oxidative Stress Crosstalk

BACKGROUND

Parkinson's disease (PD) is an age-related progressive multifactorial, neurodegenerative disease. The autophagy and Keap1-Nrf2 axis system are both implicated in the oxidative-stress response, metabolic stress, and innate immunity, and their dysregulation is associated with pathogenic processes in PD. Phloretin (PLT) is a phenolic compound reported possessing anti-inflammatory and antioxidant activities.

OBJECTIVE

To evaluate the neuroprotective potential of PLT in PD via modulating the autophagy-antioxidant axisMethods:The neuroprotective effect of PLT was evaluated in vitro using rotenone (ROT) exposed SH-SY5Y cell line and in vivo using ROT administered C57BL/6 mice. Mice were administered with PLT (50 and 100 mg/kg, p.o.) concomitantly with ROT (1 mg/kg, i.p) for 3 weeks. Locomotive activity and anxiety behaviors were assessed using rotarod and open field tests respectively. Further apoptosis (Cytochrome-C, Bax), α-Synuclein (α-SYN), tyrosine hydroxylase (TH), antioxidant proteins (nuclear factor erythroid 2-related factor 2 (NRF2), heme oxygenase-1 (HO-1) and autophagic (mTOR, Atg5,7, p62, Beclin,LC3B-I/II) protein activity were evaluated both in in vitro and in vivo.

RESULTS

PLT improved locomotive activity and anxiety-like behavior in mice. Further PLT diminished apoptotic cell death, α-SYN expression and improved the expression of TH, antioxidant, and autophagic regulating protein.

CONCLUSION

Taken together, present data deciphers that the PLT effectively improves motor and non-motor symptoms via modulating the mTOR/NRF2/p62 pathway-mediated feedback loop. Hence, PLT could emerge as a prospective disease-modifying drug for PD management.

Differential contributions of depression, apathy, and anxiety to neuropsychological performance in Parkinson's disease versus essential tremor

INTRODUCTION

Mood symptoms are common features of Parkinson's disease (PD) and essential tremor (ET) and have been linked to worse cognition. The goals of the present study were to compare the severity of anxiety, apathy, and depressive symptoms in PD, ET, and healthy controls (HC) and to examine differential relationships between mood and cognition.

METHOD

Older adults with idiopathic PD (N = 448), ET (N = 128), or HC (N = 136) completed a multi-domain neuropsychological assessment consisting of memory, executive function, and attention/working memory domains. Participants also completed self-reported mood measures. Between-group differences in mood and cognition were assessed, and hierarchical regression models were conducted to examine relationships between mood and cognition in each group.

RESULTS

Relative to the HC group, the PD and ET groups reported more mood symptoms and scored lower across all cognitive measures. There were no differences between the two movement disorder groups. Mood variables explained 3.9-13.7% of the total variance in cognitive domains, varying by disease group. For PD, apathy was the only unique predictor of executive function (β = -.114, p = .05), and trait anxiety was the only unique predictor of attention/working memory (β = -.188, p < .05). For ET, there were no unique predictors, though the overall models significantly predicted performance in the executive function and attention/working memory domains.

CONCLUSIONS

In a large cohort of ET and PD, we observed that the two groups had similar self-reported mood symptoms. Mood symptoms were differentially associated with cognition in PD versus ET. In PD, increased apathy was associated with worse executive function and higher trait anxiety predicted worse attention/working memory. For ET, there were no unique predictors, though the overall mood symptom severity was related to cognition. Our study highlights the importance of considering the relationship between mood and neuropsychological performance in individuals with movement disorders.

NLRP3 inflammasomes: A potential target to improve mitochondrial biogenesis in Parkinson's disease

Parkinson's disease (PD) is a common neurodegenerative condition for which no approved treatment exists to prevent collective neuronal death. There is ample evidence that mitochondrial dysfunction, reactive oxygen species (ROS), and associated caspase activity underlie the pathology observed. Neurons rely on mitochondrial activity since they have such high energy consumption. Therefore, it is not surprising that mitochondrial alterations favour neuronal degeneration. In particular, mitochondrial dysregulation contributes to PD, based on the observation that mitochondrial toxins can cause parkinsonism in humans and animal models. Also, it is known that inflammatory cytokine-mediated neuroinflammation is the key pathogenic mechanism in neuronal loss. In recent years, the research has focussed on mitochondria being the platform for nucleotide-binding oligomerization domain-like receptors 3 (NLRP3) inflammasome activation. Mitochondrial dysfunction and NLRP3 activation are emerging as critical players in inducing and sustaining neuroinflammation. Moreover, mitochondrial-derived ROS and mitochondrial DNA (mtDNA) could serve as the priming signal for forming inflammasome complexes responsible for the activation, maturation, and release of pro-inflammatory cytokines, including interleukin-1(IL-1) and interleukin-18 (IL-18). The current review takes a more comprehensive approach to elucidating the link between mitochondrial dysfunction and aberrant NLRP3 activation in PD. In addition, we focus on some inhibitors of NLRP3 inflammatory pathways to alleviate the progression of PD.

Effectiveness of Acupuncture for Anxiety Among Patients With Parkinson Disease: A Randomized Clinical Trial

IMPORTANCE

One of the ordinary manifestations of Parkinson disease (PD) is anxiety, which remains untreated. Anxiety is closely associated with the accelerated progression of PD. Efficacy of acupuncture for anxiety has been reported. However, to date, there are no data on acupuncture's effectiveness on anxiety for patients with PD.

OBJECTIVE

To investigate the effect of acupuncture vs sham acupuncture for treating anxiety in patients with PD.

DESIGN, SETTING, AND PARTICIPANTS

This is randomized, double-blinded, clinical trial enrolled patients between June 20, 2021, and February 26, 2022. Final follow-up was April 15, 2022. Patients with Parkinson disease and anxiety were allocated randomly (1:1) to receive acupuncture or sham acupuncture for 8 weeks. Acupuncture operators, outcome measures evaluators, and statistical analysts were blinded to the grouping of patients. Patients were blinded to their own grouping during the study. This study took place in the Parkinson clinic of a hospital in China.

INTERVENTIONS

Real acupuncture or sham acupuncture for 8 weeks.

MAIN OUTCOMES AND MEASURES

Primary outcome was Hamilton Anxiety Scale (HAM-A) score. Secondary outcomes were scores on the Unified Parkinson Disease Rating Scale (UPDRS), 39-item Parkinson Disease Questionnaire (PDQ-39), and serum levels of the adrenocorticotropic hormone (ACTH) and cortisol (CORT).

RESULTS

Seventy eligible patients were enrolled, including 34 women (48.5%) and 36 men (51.4%). Sixty-four patients (91%) completed the intervention and the 8-week follow-up, including 30 women (46.9%) and 34 men (53.1%) with a mean (SD) age of 61.84 (8.47) years. At the end of treatment, the variation of HAM-A score was 0.22 (95% CI, -0.63 to 1.07; P = .62) between the real acupuncture and sham acupuncture groups. At the end of follow-up, the real acupuncture group had a significant 7.03-point greater (95% CI, 6.18 to 7.88; P < .001) reduction in HAM-A score compared with the sham acupuncture group. Four mild adverse reactions occurred during the study.

CONCLUSIONS AND RELEVANCE

This study found acupuncture to be an effective treatment for anxiety in patients with PD. These findings suggest that acupuncture may enhance the wellbeing of patients who have Parkinson disease and anxiety.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR2100047253.

The Effects of Safinamide Adjunct Therapy on Depression and Apathy in Patients With Parkinson's Disease: Post-hoc Analysis of a Japanese Phase 2/3 Study

Background and Purpose

Neuropsychiatric symptoms in Parkinson's disease (PD) have been shown to significantly affect quality of life (QOL). We investigated the impact of safinamide on depression and apathy when administered as an adjunct to levodopa in Japanese patients with PD.

Methods

This was a post-hoc analysis of data from a phase 2/3 clinical study of safinamide in Japanese patients with PD experiencing wearing-off (JapicCTI-153056; https://www.clinicaltrials.jp/cti-user/trial/ShowDirect.jsp?japicId=JapicCTI-153056). Patients received placebo, safinamide 50 mg, or safinamide 100 mg as an adjunct therapy. The endpoints for this analysis were changes from baseline to Week 24 in the Unified Parkinson's Disease Rating Scale (UPDRS) Part I item 3 (depression) and item 4 (apathy) scores and the Parkinson's Disease Questionnaire (PDQ-39) “emotional well-being” domain score. Subgroup analyses investigated the relationship between neuropsychologic symptoms and improvements in motor fluctuation and assessed which patient populations might be expected to obtain neuropsychologic benefit from safinamide.

Results

Compared with placebo, safinamide (both doses) significantly improved UPDRS Part I item 3 scores in the overall analysis population, and the 100-mg dose improved UPDRS Part I item 4 scores in the population with apathy at baseline. Changes in the PDQ-39 “emotional well-being” score showed numerical, but not significant, dose-related improvements. Notable reductions in depression were associated with a change in daily ON-time ≥1 h, pain during OFF-time at baseline, and female sex.

Conclusions

The results from this post-hoc analysis of the Japanese phase 2/3 study suggest that safinamide could bring benefits to patients with PD who have mild depression, pain during the OFF phase. In addition, safinamide might provide particular benefits for patients with PD who have mild apathy and female.

Diagnostic work up: Laboratory and biomarkers

This chapter will focus on the diagnostic work around sexual dysfunction in Parkinson's disease, especially laboratory tests and biomarkers. A number of methods to analyze if sexual dysfunction is caused by neural pathology, vascular dysfunction or other mechanisms are now available. Other methods can be used to differentiate between psychogenic/functional reasons behind sexual dysfunction and organic ones. The role of biomarkers for diagnosis, but also for understanding the reason behind and for counteracting sexual dysfunction is becoming more evident. There is also a rich and increasing number of scales and other instruments available for detecting and quantifying sexual hypo- and hyperactivity. When investigating the reason behind sexual dysfunction in patients with Parkinson's disease comorbidities should also be considered. Finally, early and pronounced sexual dysfunction might in some cases be an indication that differential diagnosis, like Multisystem Atrophy, should be thought about. All these aspects of the diagnostic procedures around sexual dysfunction in Parkinson's disease will be covered in this chapter.

Metabolomics profiling reveals altered lipid metabolism and identifies a panel of lipid metabolites as biomarkers for Parkinson's disease related anxiety disorder

OBJECTIVES

Anxiety disorder is a common non-motor symptom in patient with Parkinson's disease (PD). We aimed to explore its pathogenesis and identify plasma biomarkers using untargeted metabolomics analysis.

METHODS

Consecutive PD patients and healthy controls were recruited. Clinical data were assessed and patients with Parkinson's disease related anxiety disorder (PDA) were recognized. Fast plasma samples were obtained and untargeted liquid chromatography-mass spectrometry-based metabolomics analysis was performed. Based on the differentially expressed metabolites from the above metabolomics analysis, correlation analyses and receiver operating characteristic curves (ROC) were further employed.

RESULTS

According to the clinical data, PDA patients had lower plasma levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and apolipoprotein B. There were thirty-nine differentially expressed metabolites in PDA patients when compared with the other two groups from the metabolomics analysis, respectively. Fourteen lipid metabolites were simultaneously altered between these two groups, and all of them were significantly decreased. They can be further subcategorized into fatty acyls, glycerolipids, sterol lipids, sphingolipids, and prenol lipids. The plasma levels of thirteen metabolites were negatively correlated with HAMA scores except 10-oxo-nonadecanoic acid. Based on the ROC curves, the fourteen lipid metabolites can be diagnostic biomarkers for PDA patients separately and the areas under the curve of the fourteen lipid metabolites ranged from 0.681 to 0.798.

CONCLUSIONS

Significantly lower plasma lipoproteins can be found in PDA patients. A panel of fourteen lipid metabolites were also significantly decreased and can be clinical biomarkers for the diagnosis of PDA patients.