Female Parkinson's Disease Patients Research Articles

[Alterations in erythrocytic oligomeric alpha-synuclein in patients with Parkinson's disease and multiple system atrophy].

Objective: To analyze the content of α-synuclein oligomer(O-α-Syn) in erythrocytes in patients with Parkinson's disease (PD) and multiple system atrophy (MSA) and the correlation with clinical symptoms. Methods: Two hundred and ninety-six PD patients and 85 MSA patients were recruited from the Department of Functional Neurosurgery and Neurology of Xuanwu Hospital, Capital Medical University from July 2020 to October 2021. Four hundred and three healthy controls (HC) were recruited from the Beijing Longitudinal Study of Aging community cohort during the same period. The levels of RBC-O-α-Syn were measured by enzyme-linked immunosorbent assay (ELISA). Univariate linear regression model was used to analyze the correlation between the content of RBD-O-α-Syn and various motor and non-motor functional scores, such as Unified Parkinson Disease Rating Scale (UPDRS) Ⅲ, Unified Multiple System Atrophy Rating Scale (UMSARS) Ⅲ, Mini-Mental State Examination (MMSE), rapid eye movement sleep disorder questionnaire-HongKong(RBDQ-HK) and Montreal Cognitive Assessment (MoCA). Receiver operating characteristic (ROC) curves was used to evaluate the specificity, sensitivity, and the area under the curve (AUC) of RBC-O-α-Syn in distinguishing PD and MSA patients from HC subjects. Results: The average age of HC subjects was (70±8) years old, the average age of PD patients was (64±9) years old, including 115 (38.9%) cases with tremor dominant PD (TD-PD), 132 cases (44.6%) of postural instability disorder predominant PD (PIGD-PD), and 142 cases (48.0%) of patients with H-Y stage 2. UPDRS Ⅲ score was 31.2±17.8. The mean age of MSA patients was (64±9) years, with the mean UMSARS Ⅱ score of 18.9±10.3. The non-motor symptoms of PD and MSA patients were significantly different from those of HC subjects (P<0.001). The levels of RBC-O-α-Syn in PD [(50±17) ng/mg] and MSA [(52±19) ng/mg] were significantly higher than those in HC subjects [(21±10) ng/mg] (P<0.001). The sensitivity and specificity of RBC-O-α-Syn in distinguishing PD patients and HC subjects were 87.16% (95%CI: 82.87%-90.50%) and 86.10% (95%CI: 82.38%-89.14%), with an AUC of 0.933 (95%CI: 0.914-0.951), and the sensitivity and specificity in distinguishing MSA patients and HC subjects were 85.88% (95%CI: 76.93%-91.74%) and 81.39% (95%CI: 77.30%-84.89%), with an AUC of 0.921 (95%CI: 0.884-0.957). The levels of RBC-O-α-Syn in PD patients with rapid eye movement sleep behavior disorder (RBD) were higher than that in PD patients without RBD [(53±16) ng/mg vs (48±17) ng/mg, P=0.029].The content of RBC-O-α-Syn in female PD patients and HC subjects was higher than that in male, but there was no significant difference between subjects of different ages and disease duration (P>0.05). In addition, RBC-O-α-Syn content was positively correlated with UPDRS Ⅲ (r=0.18, P=0.002) and the score of rapid eye movement sleep behavior disorder questionnaire(Hong Kong) (RBDQ-HK)(r=0.19, P<0.001). But there was no correlation with H-Y stage, non-motor symptoms scale (NMSS), MMSE, Moca, Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA) scores (all P>0.05). There was no correlation between RBC-O-α-Syn content and UMSARS Ⅱ, NMSS, MMSE, MoCA, HAMD, HAMA in patients with MSA (all P>0.05). Conclusions: Levels of RBC-O-α-Syn are significantly increased in PD and MSA patients. There are positive correlations between levels of RBC-O-α-Syn and scores of UPDRS Ⅲ and RBDQ-HK.

Evaluation of the role of FMR1 CGG repeat allele in Parkinson's disease from the Chinese population.

There is controversial evidence that FMR1 premutation or "gray zone" (GZ) allele (small CGG expansion, 45-54 repeats) was associated with Parkinson's disease (PD). We aimed to explore further the association between FMR1 CGG repeat expansions and PD in a large sample of Chinese origin. We included a cohort of 2,362 PD patients and 1,072 controls from the Parkinson's Disease and Movement Disorders Multicenter Database and Collaborative Network in China (PD-MDCNC) in this study and conducted repeat-primed polymerase chain reaction (RP-PCR) for the size of FMR1 CGG repeat expansions. Two PD patients were detected with FMR1 premutation (61 and 56 repeats), and the other eleven PD patients were detected with the GZ allele of FMR1 CGG repeat expansions. Those thirteen PD patients responded well to levodopa and were diagnosed with clinically established PD. Specifically, one female PD patient with GZ allele was also found with premature ovarian failure. However, compared to healthy controls, we found no significant enrichment of GZ allele carriers in PD patients or other subgroups of PD cases, including the subgroups of female, male, early-onset, and late-onset PD patients. Furthermore, we did not find any correlation between the FMR1 gene CGG repeat sizes and age at onset of PD. It suggested that FMR1 premutation was related to PD, but the GZ allele of FMR1 CGG repeat expansions was not significantly enriched in PD cases of Chinese origin. Further larger multiple ethnic studies are needed to determine further the role of the FMR1 GZ allele in PD.

Sex Differences in Brain Structure in de novo Parkinson's Disease: A Cross-Sectional and Longitudinal Neuroimaging Study.

Parkinson's disease (PD) varies in occurrence, presentation, and severity between males and females. However, the sex effects on the patterns of brain structure, cross-sectionally and longitudinally, are still unclear. We aimed to compare sex differences in brain features cross-sectionally and longitudinally using grey matter volume (GMV) and cortical thickness in a large sample of newly diagnosed drug-naive PD patients. Cognitive assessments and structural MR images of 262 PD patients (171 males) and 113 healthy controls (68 males) were selected from the Parkinson's Progression Markers Initiative. Of these, 97 PD patients (66 males) completed 12- and 24-month follow-up examinations. After regressing out the expected effects of age and sex, brain maps of GMV and cortical thickness were compared using two-sample t tests cross-sectionally and were compared using repeated measurement analyses of variance longitudinally. At baseline, male PD patients exhibited a greater extent of brain atrophy and cortical thickness reduction than females, which mainly occurred in the cerebellum, frontal lobe, parietal lobe, and temporal lobe. At follow-up, female and male PD patients showed similar dynamics of disease progression, as both groups declined over time while the females maintained the advantage. The cortical thickness of the right precentral gyrus at baseline was negatively associated with the longitudinal changes of motor function in male PD patients. The current findings might demonstrate sex effect in neuroanatomy during the course of PD, provide new insights into the neurodegenerative process, and facilitate the development of more effective sex-specific therapeutic strategies.

Olfactory Impairment Is the Main Predictor of Higher Scores at REM Sleep Behavior Disorder (RBD) Screening Questionnaire in Parkinson's Disease Patients.

Olfactory impairment and REM sleep behavior disorder (RBD) are common non-motor symptoms in Parkinson's disease (PD) patients, often preceding the onset of the specific motor symptoms and, thus, crucial for strategies directed to anticipate PD diagnosis. In this context, the specific interaction between olfactory impairment and RBD has not been clearly defined. The aim of this study was to determine the possible role of olfactory impairment and other clinical characteristics as possible predictors of higher scores at RBD screening questionnaire (RBDSQ) in a large population of PD patients. In this study, 590 PD patients were included from the Parkinson's Progression Markers Initiative. Demographic and clinical features were registered. All participants completed motor and non-motor evaluations at the baseline visit. For motor assessments, the disease severity was evaluated by the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) pars III. Regarding non-motor symptoms assessment, Montreal Cognitive Assessments (MoCA), University of Pennsylvania Smell Identification Test (UPSIT) and RBD screening questionnaire (RBDSQ) were registered. Among 590 PD patients included in this study, 111 patients with possible RBD were found (18.8%). RBD was less frequent in female PD patients (p  ≤  0.011). Among patients with or without possible RBD diagnosis, statistically significant differences in MDS-UPDRS III (23.3 ± 11.4 vs. 19.7 ± 9.1, respectively, p  ≤  0.002) and in UPSIT score (19.7 ± 8.3 vs. 22.6 ± 8.0, respectively, p  ≤  0.001) were found. Moreover, significant correlations between RBDSQ versus UPDRS III score and versus UPSIT score were observed. Multivariate linear regression analysis showed that UPSIT was the most significant predictor of higher scores at RBDSQ, while the other significant predictors were UPDRS III and age. The severity of olfactory impairment appears tightly correlated to RBD symptoms, highlighting the role of these biomarkers for PD patients. Additionally, according to this large study, our data confirmed that RBD in PD patients exhibits peculiar gender differences.

Unveiling sex-based differences in Parkinson's disease: a comprehensive meta-analysis of transcriptomic studies

BackgroundIn recent decades, increasing longevity (among other factors) has fostered a rise in Parkinson's disease incidence. Although not exhaustively studied in this devastating disease, the impact of sex represents a critical variable in Parkinson’s disease as epidemiological and clinical features differ between males and females.MethodsTo study sex bias in Parkinson’s disease, we conducted a systematic review to select sex-labeled transcriptomic data from three relevant brain tissues: the frontal cortex, the striatum, and the substantia nigra. We performed differential expression analysis on each study chosen. Then we summarized the individual differential expression results with three tissue-specific meta-analyses and a global all-tissues meta-analysis. Finally, results from the meta-analysis were functionally characterized using different functional profiling approaches.ResultsThe tissue-specific meta-analyses linked Parkinson’s disease to the enhanced expression of MED31 in the female frontal cortex and the dysregulation of 237 genes in the substantia nigra. The global meta-analysis detected 15 genes with sex-differential patterns in Parkinson’s disease, which participate in mitochondrial function, oxidative stress, neuronal degeneration, and cell death. Furthermore, functional analyses identified pathways, protein–protein interaction networks, and transcription factors that differed by sex. While male patients exhibited changes in oxidative stress based on metal ions, inflammation, and angiogenesis, female patients exhibited dysfunctions in mitochondrial and lysosomal activity, antigen processing and presentation functions, and glutamic and purine metabolism. All results generated during this study are readily available by accessing an open web resource (http://bioinfo.cipf.es/metafun-pd/) for consultation and reuse in further studies.ConclusionsOur in silico approach has highlighted sex-based differential mechanisms in typical Parkinson Disease hallmarks (inflammation, mitochondrial dysfunction, and oxidative stress). Additionally, we have identified specific genes and transcription factors for male and female Parkinson Disease patients that represent potential candidates as biomarkers to diagnosis.

Impact of COVID-19 pandemic on patients with Parkinson's disease: A meta-analysis of 13,878 patients.

BackgroundThe clinical, neuropsychological, and socioeconomic factors affecting Parkinson's disease (PD) during COVID‐19 pandemic across different populations have not been systematically studied. To address this, we conducted a meta‐analysis of factors that impact the well‐being of PD patients during the pandemic.MethodsMedline and Embase were searched for articles published between 2020 and 2022. We conducted random‐effects pooling of estimates and meta‐regression.ResultsTwenty‐seven studies involving 13,878 patients from America, Europe, Asia, and Africa were included. There is a high prevalence of decreased physical activity and exercise, and worsening motor and neuropsychiatric symptoms (17–56%). Patients in lower‐income countries more frequently reported worsening anxiety (adjusted OR [aOR] 8.94, 95% confidence interval [CI] 1.62–49.28, p = 0.012), sleep (aOR 5.16, 95% CI 1.15–23.17, p = 0.032), and PD symptoms (aOR 3.57, 95% CI 0.96–13.34, p = 0.058). Lockdown was associated with decreased exercise levels (aOR 0.13, 95% CI 0.02–0.78, p = 0.025) and worsening mood (aOR 0.48, 95% CI 0.24–0.95, p = 0.035). Younger age correlated with decreased physical activity (β −0.30, 95% CI −0.53 to −0.07, p = 0.012), exercise (β −0.11, 95% CI −0.15 to −0.07, p < 0.001), worsening PD symptoms (β −0.08, 95% CI −0.15 to −0.01, p = 0.018), and sleep (β −0.14, 95% CI −0.27 to 0, p = 0.044). Female PD patients reported a greater decrease in physical activity (β 11.94, 95% CI 2.17–21.71, p = 0.017) and worse sleep (β 10.76, 95% CI 2.81–18.70, p = 0.008).ConclusionThis large meta‐analysis of PD patients in diverse populations identified a high prevalence of physical and mental worsening during the COVID‐19 pandemic, with patients in lower‐income countries being exceptionally vulnerable.

EFFECTS OF CONSTRAINT-INDUCED MOVEMENT THERAPY ON HAND AND ARM FUNCTIONS IN PATIENTS WITH PARKINSON’S DISEASE

The aim of this research was to ascertain the effect of constraint-induced movement therapy on individuals with Parkinson's disease's hand and arm functions. Methods: It was a randomized controlled experiment that ran from December 28, 2020, to March 3, 2021, at the physical therapy departments of the University of Lahore Teaching Hospital, Lahore General Hospital and Mayo Hospital. Between the ages of 50 and 80, 40 male and female Parkinson's disease patients were divided evenly into two groups. Patients in the experimental group (n = 20) received both routine physical treatment and constraint-induced movement therapy, while patients in the control group (n = 20) received just normal physical therapy. Six hours a day, for a total of four weeks, were spent treating the patients. Frenchay Arm Test was used to evaluate patients (FAT). The data were examined using IBM's Statistical Package for Social Sciences (SPSS) version 25. Results: Data for 40 individuals were evaluated, with 17 (42.5%) men and 23 (57.50%) women, and a mean age SD of 65.28 7.28 with a minimum age of 50 and a maximum age of 78. Patients improved in both groups; the mean difference between pre- and post-test results in the experimental group was 2.060.66 (p=0.000), whereas it was -0.940.64 (p=0.000) in the control group. Contrary to conventional physical therapy alone, however, patients reported greater improvement following treatment with constraint-induced movement therapy (p=0.003). Conclusion: According to this study, constraint-induced mobility therapy helped Parkinson's disease patients' hands and arms operate better

Does dopamine deficiency affect sex-dependent prognosis in Parkinson's disease?

IntroductionA bundle of evidence indicates that biological sex is an important factor for clinical phenotypes as well as prognosis in Parkinson's disease (PD). We investigated the effect of nigrostriatal dopaminergic degeneration on longitudinal outcomes according to sex in patients with PD. MethodsWe recruited 571 consecutive drug-naïve PD patients (279 men and 292 women) who were followed up for ≥2 years after their first visit to the clinic with baseline dopamine transporter (DAT) imaging. A Cox proportional hazard model was used to compare the risk of developing levodopa-induced dyskinesia (LID), wearing-off, freezing of gait (FOG), or PD dementia (PDD) between male and female PD patients. A mediation analysis was used to determine the relationship between biological sex, striatal dopamine deficiency, and longitudinal outcomes. ResultsFemale PD patients exhibited less severely decreased DAT availability in all striatal subregions than male PD patients. The future development of wearing-off and FOG did not differ according to sex. LID developed more frequently in female PD patients than in male PD patients, while the risk of PDD conversion was higher in male PD patients than in female PD patients. In the mediation analyses, the direct effect of biological sex on the development of LID or PDD was major, while the mediating effect through the striatal DAT availability was minimal. ConclusionDifferences in longitudinal outcomes according to biological sex may be ascribed to a non-dopaminergic basis. This study suggests that therapeutic strategies targeting the extra-nigrostriatal pathway should be considered in future trials.

Risk factors for motor complications in female patients with Parkinson's disease.

To investigate the risk factors of motor complications in female patients with Parkinson's disease (PD) and the correlation between the occurrence of motor complications and sex hormone levels. According to the occurrence and types of motor complications, 103 female PD patients were divided into two groups: patients with or without the wearing-off phenomenon, patients with or without dyskinesia. Binary logistic regression analysis was performed respectively to screen for the risk factors of the wearing-off phenomenon and dyskinesia in female PD patients. Among 103 female PD patients, 44 (42.72%) had motor complications. Patients with the wearing-off phenomenon and patients with dyskinesia had higher prolactin levels than patients without the wearing-off phenomenon and patients without dyskinesia, respectively. However, the difference was no longer significant when the two groups were corrected for multiple comparisons (P < 0.0028). Multivariate analysis found that younger age at onset and higher Hoehn-Yahr (H&Y) stage were identified as independent risk factors for the wearing-off phenomenon and younger age of onset was an independent risk factor for dyskinesia in female PD patients (P < 0.05). Female PD patients have a higher incidence of motor complications. Younger age of onset and higher H&Y stage were the risk factors of the wearing-off phenomenon, and younger onset age was the risk factor of dyskinesia in female PD patients. There may be a certain correlation between the occurrence of motor complications and sex hormone levels in female PD patients, which requires further verification.

Expression of BDNF-Associated lncRNAs in Parkinson's disease.

Decreased level of neurotrophic factor brain-derived neurotrophic factor (BDNF) has been supposed to participate in the pathoetiology of Parkinson's disease (PD). However, the underlying mechanisms of its dysregulation and the functional network between this factor and other transcripts have not been elucidated. In the current study, we measured expressions of BDNF, and four related long non-coding RNAs, namely BDNF-AS, MIR137HG, MIAT and PNKY in blood of PD patients and normal controls to find their expression levels in these patients and propose a possible mechanism for dysregulation of BDNF in PD patients. Notably, we detected down-regulation of all transcripts in the circulation of PD patients compared with controls. There was no significant difference in expression of either gene between male and female PD patients or patients receiving L-Dopa versus those receiving other drugs. Expression of none of genes was correlated with age, disease duration, disease stage, MMSE or UPDRS. Dynamic principal component analysis showed that expression levels of these genes almost clearly separated samples collected from healthy controls and PD patients into their respective groups. This suggests that the observed lncRNAs differences are associated with the pathophysiology of PD, and these lncRNAs might constitute an important biomarker signature for PD.

CSF and Serum Levels of Inflammatory Markers in PD: Sparse Correlation, Sex Differences and Association With Neurodegenerative Biomarkers.

BackgroundAn involvement of the central-nervous and peripheral, innate and adaptive immune system in the pathogenesis of Parkinson's disease (PD) is nowadays well established.ObjectivesWe face several open questions in preparation of clinical trials aiming at disease-modification by targeting the immune system: Do peripheral (blood) inflammatory profiles reflect central (CSF) inflammatory processes? Are blood/CSF inflammatory markers associated with CSF levels of neurodegenerative/PD-specific biomarkers?MethodsUsing a multiplex assay we assessed 41 inflammatory markers in CSF/serum pairs in 453 sporadic PD patients. We analyzed CSF/serum correlation as well as associations of inflammatory markers with clinical outcome measures (UPDRS-III, H&Y, MoCA) and with CSF levels of α-synuclein, Aβ1−42, t-Tau, p181-Tau and NFL. All analyses were stratified by sex as the immune system shows relevant sex-specific differences.ResultsCorrelations between CSF and serum were sparse and detected in only 25% (9 out of 36) of the analysable inflammatory markers in male PD patients and in only 38% (12 out of 32) of female PD patients. The most important pro-inflammatory mediators associated with motor and cognitive decline as well as with neurodegenerative/PD-specific biomarkers were FABP, ICAM-1, IL-8, MCP-1, MIP-1-beta, and SCF. Results were more robust for CSF than for serum.InterpretationLevels of central-nervous and peripheral inflammatory markers might be regulated independently of each other with CSF inflammatory markers reflecting CNS pathology more accurately than peripheral markers. These findings along with sex-specific characteristics have to be considered when designing clinical trials aiming at disease-modification by targeting the immune system.

Characteristics of sagittal spinopelvic alignment in patients with Parkinson's disease.

IntroductionThe aim of this study was to characterize the associations between sagittal spinopelvic alignment and motor symptoms in patients with Parkinson's disease (PD).MethodsThe study included patients with idiopathic PD (aged <80 years and with abnormal posture). All patients underwent whole‐spine lateral and coronal radiography. Sagittal spinopelvic alignment was evaluated using nine parameters. Motor symptoms were evaluated using the Movement Disorder Society‐sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS‐UPDRS) part III score—with bradykinesia and axial motor sub‐scores. Multivariate analysis was used to analyze associations between motor symptoms and sagittal spinopelvic alignment in PD patients according to sex.ResultsThe study subjects were 79 PD patients (39 men, 40 women; median age, 70 years). Clear sex‐related differences were noted. In male patients, the MDS‐UPDRS part III score correlated significantly with cervical sagittal vertical axis (SVA), and bradykinesia and axial motor scores correlated significantly with SVA, cervical SVA, and T1 slope. In female patients, the MDS‐UPDRS part III score correlated significantly with thoracic kyphosis, bradykinesia score correlated significantly with cervical SVA and thoracic kyphosis, and the axial motor score correlated significantly with SVA, cervical SVA, T1 slope, sacral slope, and pelvic tilt.ConclusionOur results showed clear correlations among various motor symptoms and sagittal global alignment in PD patients and that these correlations are different in female PD patients and their male counterparts.

Differences in the Presentation and Progression of Parkinson's Disease by Sex.

Previous studies reported various symptoms of Parkinson's disease (PD) associated with sex. Some were conflicting or confirmed in only one study. We examined sex associations to PD phenotypes cross-sectionally and longitudinally in large-scale data. We tested 40 clinical phenotypes, using longitudinal, clinic-based patient cohorts, consisting of 5946 patients, with a median follow-up of 3.1 years. For continuous outcomes, we used linear regressions at baseline to test sex-associated differences in presentation, and linear mixed-effects models to test sex-associated differences in progression. For binomial outcomes, we used logistic regression models at baseline and Cox regression models for survival analyses. We adjusted for age, disease duration, and medication use. In the secondary analyses, data from 17 719 PD patients and 7588 non-PD participants from an online-only, self-assessment PD cohort were cross-sectionally evaluated to determine whether the sex-associated differences identified in the primary analyses were consistent and unique to PD. Female PD patients had a higher risk of developing dyskinesia early during the follow-up period, with a slower progression in activities of daily living difficulties, and a lower risk of developing cognitive impairments compared with male patients. The findings in the longitudinal, clinic-based cohorts were mostly consistent with the results of the online-only cohort. We observed sex-associated contributions to PD heterogeneity. These results highlight the necessity of future research to determine the underlying mechanisms and importance of personalized clinical management. © 2020 International Parkinson and Movement Disorder Society.

Can sex influence the neurocognition of language? Evidence from Parkinson's disease

Parkinson's disease (PD), which involves basal ganglia degeneration, affects language as well as motor function. However, which aspects of language are impaired in PD and under what circumstances remains unclear. We examined whether lexical and grammatical aspects of language are differentially affected in PD, and whether this dissociation is moderated by sex as well as the degree of basal ganglia degeneration. Our predictions were based on the declarative/procedural model of language. The model posits that grammatical composition, including in regular inflection, depends importantly on left basal ganglia procedural memory circuits, whereas irregular and other lexicalized forms are memorized in declarative memory. Since females tend to show declarative memory advantages as compared to males, the model further posits that females should tend to rely on this system for regulars, which can be stored as lexicalized chunks. We tested non-demented male and female PD patients and healthy control participants on the intensively studied paradigm of English regular and irregular past-tense production. Mixed-effects regression revealed PD deficits only at regular inflection, only in male patients. The degree of left basal ganglia degeneration, as reflected by right-side hypokinesia, predicted only regular inflection, and only in male patients. Left-side hypokinesia did not show this pattern. Past-tense frequency effects suggested that the female patients retrieved regular as well as irregular past-tense forms from declarative memory, whereas the males retrieved only irregulars. Sensitivity analyses showed that the pattern of findings was robust. The results, which are consistent with the declarative/procedural model, suggest a grammatical deficit in PD due to left basal ganglia degeneration, with a relative sparing of lexical retrieval. Female patients appear to compensate for this deficit by relying on chunks stored in declarative memory. More generally, the study elucidates the neurocognition of inflectional morphology and provides evidence that sex can influence how language is computed in the mind and brain.

The Association Analysis of GPNMB rs156429 With Clinical Manifestations in Chinese Population With Parkinson's Disease.

Background: The mechanisms of Parkinson's disease (PD) include complicated genetic factors. The roles of newly found risk genes need to be further verified among different ethnicities. In a two-stage meta-analysis, single nucleotide polymorphism (SNP) of rs156429 in glycoprotein non-metastatic melanoma protein B (GPNMB) was reported to be associated with PD. So far clinical studies have focused on association between rs156429 and PD onset, however there is little evidence linking rs156429 with PD symptoms.Objective: This study aimed to investigate the possible association of GPNMB rs156429 with PD manifestations among southeastern Chinese people.Methods: Demographic variables, disease-related factors, and motor and non-motor assessments of 511 PD patients were collected. Polymerase chain reaction (PCR) and SNaPshot technique were used to detect GPNMB rs156429. The associations of rs156429 with PD rating scales and clinical manifestations were analyzed by Kruskal-Wallis test and logistic regression model separately.Results: Kruskal-Wallis test and logistic regression model failed to reveal an association between GPNMB rs156429 and scores from Montreal Cognitive Assessment (MoCA) (p = 0.037; p = 1.000 after correction), and pain symptoms of 511 PD patients (p = 0.008, OR = 0.59, 95% CI = 0.40–0.87, overdominant model after adjustment; p = 0.168 after correction, overdominant model after adjustment). However, further analysis based on genders showed that GPNMB rs156429 might have a trend for being associated with cognitive dysfunction (Mini-Mental State Examination (MMSE), p = 0.064 after correction; MoCA, p = 0.064 after correction) and pain symptoms (p = 0.063 after correction, overdominant model after adjustment) in female PD patients but not male patients.Conclusions: This study revealed that GPNMB rs156429 might have a trend for being associated with cognitive dysfunction and pain symptoms of female PD patients in the southeastern Chinese population. Further studies from a larger sample size are needed to confirm these findings.

Osteoporosis in Parkinson's Disease: Relevance of Distal Radius Dual-Energy X-Ray Absorptiometry (DXA) and Sarcopenia

Osteoporotic fractures are common in Parkinson's disease (PD). Standard dual-energy X-ray absorptiometry (DXA) measuring bone mineral density (BMD) at the femoral neck and lumbar spine (central sites) has suboptimal sensitivity in predicting fracture risk in the general population. An association between sarcopenia and osteoporosis in PD has not been studied. We compared BMD and osteoporosis prevalence in PD patients vs controls; determined the osteoporosis detection rates using central alone vs central plus distal radius DXA; and analyzed factors (in particular, sarcopenia) associated with osteoporosis. One hundred and fifty-six subjects (102 patients with PD, 54 spousal/sibling controls) underwent femoral neck-lumbar spine-distal radius DXA. Seventy-three patients and 46 controls were assessed for sarcopenia using whole-body DXA and handgrip strength. Patients underwent clinical and serum biochemical evaluations. PD patients had significantly lower body mass index compared to controls. After adjustment for possible confounders, distal radius BMD and T-scores were significantly lower in PD patients compared to controls, but not at the femoral neck/lumbar spine. With distal radius DXA, an additional 11.0% of patients were diagnosed with osteoporosis (32.0% to 43.0%), vs 3.7% in controls (33.3% to 37.0%) additionally diagnosed; this increase was largely driven by the markedly higher detection rate in female PD patients. Female gender (adjusted odds ratio [ORadjusted] = 11.3, 95% confidence interval [CI]: 2.6–48.6) and sarcopenia (ORadjusted = 8.4, 95% CI: 1.1–64.9) were independent predictors for osteoporosis in PD. Distal radius DXA increased osteoporosis detection, especially in female PD patients, suggesting that diagnostic protocols for osteoporosis in PD could be optimized. A close association between osteoporosis and sarcopenia was documented for the first time in PD, which has important implications for clinical management and future research.

Sex‐specific association of urate and levodopa‐induced dyskinesia in Parkinson’s disease

As a major antioxidant, uric acid (UA) is known to be associated with the clinical progression of Parkinson's disease (PD). This study investigated whether baseline UA levels are associated with the risk for levodopa-induced dyskinesia (LID) in PD in a sex-dependent manner. In all, 152 patients with de novo PD (78 males and 74 females) who were followed up for >2years were enrolled. The effect of baseline serum UA levels on LID-free survival was assessed by Cox regression, separately for sex, whilst being adjusted for potential confounding factors. The optimal UA level cut-off value to determine the high-risk group for LID was set using Contal and O'Quigley's method. Levodopa-induced dyskinesia developed in 23 (29.5%) male patients and 30 (40.5%) female patients. Cox regression showed a significant interaction between UA level and sex. Higher UA levels were associated with a higher risk for LID in male PD patients (hazard ratio 1.380; 95% confidence interval 1.038-1.835; P=0.027), although this relationship was not observed in female PD patients. The optimal UA level cut-off for LID in male PD was 7.2mg/dl, and the high UA group had a 5.7-fold higher risk of developing LID than the low UA group. Contrary to a presumptive beneficial role of UA, the present study demonstrated that higher UA levels are associated with increased risk of LID occurrence in male patients with PD, suggesting a sex-dependent role of UA in LID.

Parkinson's disease and skin cancer risk: a nationwide population-based cohort study in Korea.

Previous studies have reported that patients with Parkinson's disease (PD) have a significantly lower risk of cancer. Studies reporting prevalence of skin cancers in Parkinson's disease mostly involve Caucasians. A nationwide population-based study was conducted to determine the risk of skin cancer in patients diagnosed with PD in Korea. Data obtained from National Health Insurance Claims records were used to retrieve information about 70780 patients with newly diagnosed PD between January 2010 and December 2015. The control group included 353900 sex- and age-matched patients without PD. In this nationwide population-based cohort study, we investigated the association between PD and skin cancer. The overall hazard ratio (HR) of skin cancers in patients with PD was 1.169 (95% CI, 1.005-1.359) compared with non-PD group. Among patients with PD, males aged above 65 had a 2.8-fold increase in the risk for melanoma development than the non-PD group (HR, 2.825; 95% CI, 1.395-5.721). In addition, female PD patients aged above 65years showed a 1.3-fold increase in non-melanoma skin cancer risk than the non-PD group (HR, 1.305; 95% 1.073-1.589). Compared with the general population, Korean patients diagnosed with PD had a greater risk of skin cancer. Especially, male patients aged 65years and above, and diagnosed with PD had a significant risk of melanoma development compared with control.

CNTNAP4 deficiency in dopaminergic neurons initiates parkinsonian phenotypes.

Rationale: Contactin-associated protein-like 4 (CNTNAP4) belongs to the neurexin superfamily and has critical functions in neurological development and synaptic function. Loss of CNTNAP4 in interneurons has been linked to autism, schizophrenia, and epilepsy. CNTNAP4 is also highly enriched in dopaminergic (DA) neurons in the substantia nigra (SN), however, few studies have investigated the role of CNTNAP4 in DA neurons, and whether CNTNAP4 deficiency in DA neurons contributes to Parkinson's disease (PD) remains unclear.Methods: Effects of CNTNAP4 knockdown or overexpression on the DA MN9D cell line were assessed via Western blotting, immunocytochemistry, and RNA sequencing. An in vivo animal model, including CNTNAP4 knockout mice and stereotaxic injections of adeno-associated viral short-hairpin RNA with the tyrosine-hydroxylase promotor to silence CNTNAP4 in the SN, as well as the resulting physiological/behavioral effects, were evaluated via behavioral tests, Western blotting, immunohistochemistry, and transmission electron microscopy. Enzyme-linked immunosorbent assays (ELISAs) were performed to examine the cerebrospinal fluid (CSF) and plasma CNTNAP4 concentrations in PD patients.Results: We demonstrated that CNTNAP4 knockdown induced mitophagy and increased α-synuclein expression in MN9D cells. CNTNAP4 knockdown in the SN induced PD-like increases in SN-specific α-synuclein expression, DA neuronal degeneration, and motor dysfunction in mice. In addition, CNTNAP4 knockdown in SN-DA neurons increased autophagosomes and reduced synaptic vesicles in the SN. Furthermore, CNTNAP4 knockout mice showed movement deficits, nigral DA degeneration, and increased autophagy, which were consistent with the SN-specific knockdown model. We also found that CSF and plasma CNTNAP4 expression was increased in PD patients; in particular, plasma CNTNAP4 was increased in male PD patients compared with controls or female PD patients.Conclusion: Our findings suggest that CNTNAP4 deficiency may initiate phenotypes relevant to PD, of which we elucidated some of the underlying mechanisms.

Role of LRRK2 variant p.Gly2019Ser in patients with Parkinsonism.

Background & objectives:Parkinsonian disorder, including Parkinson's disease (PD), is an aetiologically complex neurodegenerative disorder. Mutations in leucine-rich repeat kinase 2 (LRRK2) gene have been implicated in an autosomal dominant form of PD with variable penetrance. The identification of a common LRRK2 variant (p.Gly2019Ser) in dementia with Lewy bodies indicated its potential role in Parkinsonian disorder. The current study was aimed to identify the p.Gly2019Ser variant in Indian patients with Parkinsonian disorder.Methods:The patient group consisting of 412 classical PD patients, 107 PD patients with cognitive impairment, 107 patients with Parkinson plus syndrome and 200 unrelated controls were recruited from eastern part of India. The allele representing p.Gly2019Ser variant was screened by polymerase chain reaction followed by restriction fragment length polymorphism analysis.Results:The p.Gly2019Ser variant was identified in an East Indian young-onset female PD patient in a heterozygous state having several motor and autonomic problems without disturbed cognition. Her younger brother, sister and elder son harbouring the same mutation were asymptomatic carriers for the variant. However, the influence of DNM3 on decreased disease onset in this family was not clear.Interpretation & conclusions:Identification of the p.Gly2019Ser variant in only one patient among a large number of Indian patients (n=626) with Parkinsonian disorder in our study suggests a limited role of the LRRK2 variant towards disease pathogenesis.