Signs of early cellular dysfunction in multiple system atrophy

Impaired novelty P3 potentials in multiple system atrophy—correlation with orthostatic hypotension

UVB Radiation Induces Apoptosis in Keratinocytes by Activating a Pathway Linked to “BLT2-Reactive Oxygen Species”

Vestibular-evoked myogenic potentials (VEMPs) can help in assessing otolithic neural pathway in the brainstem, which may also contribute to the cardiovascular autonomic function. Parkinson's disease (PD) is associated with altered VEMP responses; however, the associations between VEMP abnormalities and multiple system atrophy (MSA) remain unknown. Therefore, we compared the extent of otolith dysfunction using ocular (oVEMP) and cervical VEMPs between patients with MSA and PD. We analyzed the clinical features, VEMP, and head-up tilt table test (HUT) findings using the Finometer in 24 patients with MSA and 52 with de novo PD who had undergone neurotologic evaluation at a referral-based university hospital in South Korea from January 2021 to March 2023. MSA was associated with bilateral oVEMP abnormalities (odds ratio [95% confidence interval] = 9.19 [1.77-47.76], p = 0.008). The n1-p1 amplitude was negatively correlated with the Unified Multiple System Atrophy Rating Scale I-II score in patients with MSA (r = -0.571, p = 0.033), whereas it did not correlate with the Movement Disorder Society-Unified Parkinson's Disease Rating Scale-III score in patients with PD (r = -0.051, p = 0.687). The n1 latency was negatively correlated with maximum changes in systolic blood pressure within 15 s during HUT in patients with PD (r = -0.335, p = 0.040) but not in those with MSA (r = 0.277, p = 0.299). Bilaterally abnormal oVEMP responses may indicate the extent of brainstem dysfunction in MSA. oVEMP reflects the integrity of otolith-autonomic interplay, reliably assists in differentiating between MSA and PD, and helps infer clinical decline.

PurposeThe diagnosis of probable multiple system atrophy relies on the presence of severe cardiovascular or urogenital autonomic failure. Erectile dysfunction is required to fulfil the latter criterion in men, whereas no corresponding item is established for women. In this study, we aimed to investigate sexual dysfunction in women with multiple system atrophy.MethodsWe administered the Female Sexual Function Index questionnaire and interviewed women with multiple system atrophy and age-matched controls regarding the presence of “genital hyposensitivity.”ResultsWe recruited 25 women with multiple system atrophy and 42 controls. Female Sexual Function Index scores in sexually active women with multiple system atrophy were significantly lower (multiple system atrophy = 10; 15.4, 95% CI [10.1, 22.1], controls = 37; 26.1 [24.1, 28.1], p = 0.0004). The lowest scores concerned the domains of desire, arousal and lubrication. Genital hyposensitivity was reported by 56% of the patients with multiple system atrophy and 9% controls (p < 0.0001).ConclusionsSexual dysfunction is highly prevalent in women with multiple system atrophy. Screening for disturbances in specific sexual domains should be implemented in the clinical evaluation of women with suggestive motor symptoms.

Gastrointestinal symptoms such as nausea, abdominal pain, and bloating are frequent complaints in patients with Parkinson disease (PD) and in patients with multiple system atrophy (MSA), and may be associated with delayed gastric emptying (GE). Although several GE studies in patients with PD have been performed, scant data exist in patients with MSA. We assessed GE half-times (T50) in 12 patients with MSA and compared them with those of 12 patients with PD and 12 age-matched healthy controls.GE was estimated scintigraphically using the left anterior oblique method after ingestion of a (99m)Tc colloid-labeled balanced semi-solid meal (yogurt). GE data were obtained every 15 minutes until there was complete emptying of the stomach. Blood pressure, heart rate, plasma glucose and glucosylated hemoglobin were regularly determined. Reproducibility of the GE technique was excellent (Bland-Altman analysis, limits of agreement: -2.3 to 2.8). T50 was longer in MSA (82+/-3.4 min) and in PD (90.6+/-3.9 min) patients compared with controls (46.2+/-0.7) (two-way ANOVA, p<0.0001). T50 did not differ between patients with MSA and those with PD. No correlation existed between T50 and age, duration of the disease, magnitude of postprandial hypotension, levels of plasma glucose and glucosylated hemoglobin (Kendall's tau, p>0.05). Our results suggest that patients with MSA have GE rates similar to those of patients with PD, but slower than healthy age matched individuals. It remains to be investigated whether gastrointestinal dysfunction in MSA is related to both brain and peripheral pathology, as is presumed for PD.

Autonomic dysfunction in multiple system atrophy (MSA) comprises cardinal symptoms of orthostatic hypotension (OH) and urinary incontinence. Additionally, cardiovagal and sudomotor abnormalities can be present. Previous studies compared hand skin temperature and its response to cooling in subjects with probable MSA and Parkinson's disease (PD). Significant differences were found indicating that disturbed thermoregulation belongs to MSA autonomic features and could be helpful in differentiation of MSA from PD. The objective of this study was to improve our knowledge about impaired thermoregulation of distal extremities in MSA with parkinsonian features (MSA-P) and PD and to assess the possible interrelations for the different subtypes of autonomic dysfunction in a large cohort of MSA-P, PD and control patients. The patients underwent a standard cooling-rewarming procedure, termed ice test (IT). Electroneurography, heart rate variability, sympathetic skin response and orthostatic tests were performed for the subdivision of the patients. The prevalence of pathological IT was slightly increased in MSA compared with PD and control groups. The presence of pathological IT was related with older patient's age in PD and control groups significantly (p<0.05). This relation was absent for the MSA patients, who themselves were significantly younger (p=0.001). Significant association between the presence of pathological IT and OH was determined (p<0.001). Defective thermoregulation of distal extremities seems to be more severe in the MSA patients. The dysfunction of preganglionic sympathetic neurons might be involved in impaired response to cooling for MSA. The results suggest pathophysiological affinity of impaired sympathetic neurovascular regulation between pathological IT and OH.

Recent post-mortem studies reported 22-37% of patients with multiple system atrophy can develop cognitive impairment. With the aim of identifying associations between cognitive impairment including memory impairment and α-synuclein pathology, 148 consecutive patients with pathologically proven multiple system atrophy were reviewed. Among them, 118 (79.7%) were reported to have had normal cognition in life, whereas the remaining 30 (20.3%) developed cognitive impairment. Twelve of them had pure frontal-subcortical dysfunction, defined as the presence of executive dysfunction, impaired processing speed, personality change, disinhibition or stereotypy; six had pure memory impairment; and 12 had both types of impairment. Semi-quantitative analysis of neuronal cytoplasmic inclusions in the hippocampus and parahippocampus revealed a disease duration-related increase in neuronal cytoplasmic inclusions in the dentate gyrus and cornu ammonis regions 1 and 2 of patients with normal cognition. In contrast, such a correlation with disease duration was not found in patients with cognitive impairment. Compared to the patients with normal cognition, patients with memory impairment (pure memory impairment: n = 6; memory impairment + frontal-subcortical dysfunction: n = 12) had more neuronal cytoplasmic inclusions in the dentate gyrus, cornu ammonis regions 1-4 and entorhinal cortex. In the multiple system atrophy mixed pathological subgroup, which equally affects the striatonigral and olivopontocerebellar systems, patients with the same combination of memory impairment developed more neuronal inclusions in the dentate gyrus, cornu ammonis regions 1, 2 and 4, and the subiculum compared to patients with normal cognition. Using patients with normal cognition (n = 18), frontal-subcortical dysfunction (n = 12) and memory impairment + frontal-subcortical dysfunction (n = 18), we further investigated whether neuronal or glial cytoplasmic inclusions in the prefrontal, temporal and cingulate cortices or the underlying white matter might affect cognitive impairment in patients with multiple system atrophy. We also examined topographic correlates of frontal-subcortical dysfunction with other clinical symptoms. Although no differences in neuronal or glial cytoplasmic inclusions were identified between the groups in the regions examined, frontal release signs were found more commonly when patients developed frontal-subcortical dysfunction, indicating the involvement of the frontal-subcortical circuit in the pathogenesis of frontal-subcortical dysfunction. Here, investigating cognitive impairment in the largest number of pathologically proven multiple system atrophy cases described to date, we provide evidence that neuronal cytoplasmic inclusion burden in the hippocampus and parahippocampus is associated with the occurrence of memory impairment in multiple system atrophy. Further investigation is necessary to identify the underlying pathological basis of frontal-subcortical dysfunction in multiple system atrophy.

Cerebral small vessel disease (CSVD) has not been systematically studied in patients with multiple system atrophy (MSA). We sought to explore whether MSA patients suffer from a heavier CSVD burden relative to healthy individuals and whether CSVD has a relationship with motor, cognitive, and emotional dysfunction in patients with MSA. This study consecutively recruited 190 MSA patients and 190 matched healthy controls whose overall CSVD burden and single CSVD imaging markers (including white matter hyperintensity (WMH), microbleeds, lacunes, and enlarged perivascular spaces (EPVS)) were measured. Of the MSA patients, 118 completed multi-dimensional outcome assessments. Spearman's correlations and multivariable linear regressions were performed. We observed a greater burden of overall CSVD, WMH, and EPVS in MSA patients compared with controls, but not for microbleeds and lacunes. Motor dysfunction and cognitive impairment were significantly worse in subjects with severe CSVD than those with none-to-mild CSVD. In patients with MSA, the severity of CSVD burden was positively associated with motor impairments as measured by the Unified Multiple System Atrophy Rating Scale-II (β= 2.430, p = 0.039) and Scale for the Assessment and Rating of Ataxia (β= 1.882, p = 0.015). Of CSVD imaging markers, different associations with MSA outcomes were displayed. WMH was associated with motor, cognitive, and emotional deficits, while the EPVS in the centrum semiovale, basal ganglia, and hippocampus regions was correlated only with motor severity, anxiety, and cognition, respectively. Similar findings were noted in MSA-cerebellar and MSA-parkinsonian patients. Concomitant CSVD may be correlated with worse multi-dimensional dysfunction in patients with MSA.

Few studies have compared cognitive functions in multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and Parkinson's disease (PD). To compare the results of cognitive function tests in the three diseases and examine their relation with the severity of parkinsonism. Clinic-based open prospective study. Global cognitive function tests and tests specific for frontal lobe functions were used in 25 cases of each disease. UPDRS III was used to measure the severity of parkinsonism. ANOVA was done for group comparisons, followed by t-test for independent samples with Bonferroni correction. Pearson's correlation test was done to assess the relation between severity of parkinsonism and cognitive functions. The severity of parkinsonism was worst in PD followed by PSP and least in MSA. Patients with PSP exhibited the worst performance in both sets of cognitive tests. Even though patients with MSA did better than PD in global function tests, they performed worse than PD in some frontal function tests. There was a negative correlation between severity of parkinsonism and scores in cognitive tests in the MSA group but not in others. Global and frontal dysfunction was worst in PSP. The frontal dysfunction in MSA was more severe than PD, correlated with the severity of parkinsonism and was worse in clinically probable than possible cases of MSA. The severity of cognitive dysfunction in these diseases may be related to the distribution and extent of pathological changes affecting the striato-frontal circuits in them.

Catalase overexpression attenuates angiotensinogen expression and apoptosis in diabetic mice

Distinct clinical features of predominant pre-synaptic and trans-synaptic nigrostriatal dysfunction in multiple system atrophy

Choroid plexus alterations correlate with cognitive impairment in multiple system atrophy.

This chapter review summarized the epidemiology, pathophysiology, and management of bladder dysfunction in patients with multiple system atrophy (MSA). Since motor disorders in MSA often mimic those in Parkinson’s disease (PD), the different bladder disorders between these two diseases are worth considering; the identification of the specific bladder disorder aids the differential diagnosis of MSA, PD, and other MSA mimics. A bladder disorder is often the sole initial manifestation of MSA, and such patients see urologists or physicians first. Difficult emptying in MSA needs particular care at a neurology clinic. The collaboration of neurologists and urologists is highly recommended for the improvements of patients’ quality of life.KeywordsMultiple system atrophyParkinson’s diseaseDetrusor hyperactivity with impaired contraction (DHIC)Detrusor-sphincter dyssynergia (DSD)Neurogenic sphincter electromyography (EMG)

Parkinson's disease (PD), diffuse Lewy body disease (DLBD), and multiple system atrophy (MSA) constitute the three major neurodegenerative disorders referred to as synucleinopathies because both genetic and pathological results implicate the α-synuclein protein in their pathogenesis. PD and DLBD are recognized as closely related diseases with substantial clinical and pathological overlap. MSA, on the other hand, has a distinctive clinical presentation and neuropathological profile. In this review, we will summarize the evidence linking α-synuclein to these three disorders. Hundreds of patients with point or copy number mutations in the gene encoding α-synuclein, SNCA, have been reported in the literature in association with hereditary, autosomal dominant forms of PD, DLBD, or neurodegenerative disease with parkinsonism. The copy number mutations show a dosage effect with age at onset and severity correlating with the number of extra copies of SNCA a patient carries. Common variation in and around the SNCA gene has also been found by genome-wide association studies to be associated with increased risk for apparently sporadic PD, with some evidence that these variants exert their effect through modest increases in α-synuclein expression. Complementing the genetic evidence linking α-synuclein to PD and DLBD is the pathological finding that α-synuclein is a major constituent of Lewy bodies and Lewy neurites in the brains of patients with the common sporadic form of PD. On the other hand, there is little genetic evidence linking SNCA to MSA despite strong neuropathological evidence of α-synuclein aggregation in oligodendroglial cells in MSA patients. Evidence is now emerging that α-synuclein aggregates can have different protein conformations, referred to as strains, similar to what has been shown in prion disease. The different phenotypes in hereditary PD/DLBD versus MSA are likely, therefore, to be the result not only of how specific mutations affect protein expression and turnover, but also a more complex interaction between intrinsic and extrinsic factors governing aggregation and strain formation.

Asperlin induces G2/M arrest through ROS generation and ATM pathway in human cervical carcinoma cells