To determine whether REM sleep behavior disorder (RBD) in Parkinson disease (PD) is associated with lesions and dysfunctions of the autonomic nervous system by evaluating enteric phosphorylated ...α-synuclein histopathology (PASH) and permeability.
A total of 45 patients with PD were included in this cross-sectional study. RBD was diagnosed on the basis of a standardized clinical interview and confirmed by polysomnography. For each patient, 5 biopsies were taken at the junction between the sigmoid and descending colon during the course of a rectosigmoidoscopy. For the detection of enteric PASH, 2 colonic biopsies were analyzed by immunohistochemistry with antibodies against phosphorylated α-synuclein and PGP9.5 in 43 patients (2 patients were excluded because only 1 biopsy was available). The paracellular permeability and transcellular permeability were evaluated by measuring sulfonic acid and horseradish peroxidase flux, respectively, in the 3 remaining biopsies mounted in Ussing chambers.
Enteric PASH was more frequent in the subgroup of patients with PD with RBD compared to patients without RBD (18 of 28, 64.3%, vs 2 of 15, 13.3%, respectively,
< 0.01). No differences were observed in intestinal permeability between patients with PD with and without RBD.
Patients with PD and RBD have a greater frequency of synuclein pathology in the enteric nervous system, suggesting that RBD is associated with widespread synuclein neuropathology.
Spinal muscular atrophy (SMA) is a monogenic disorder caused by loss of function mutations in the survival motor neuron 1 gene, which results in a broad range of disease severity, from neonatal to ...adult onset. There is currently a concerted effort to define the natural history of the disease and develop outcome measures that accurately capture its complexity. As several therapeutic strategies are currently under investigation and both the FDA and EMA have recently approved the first medical treatment for SMA, there is a critical need to identify the right association of responsive outcome measures and biomarkers for individual patient follow-up. As an approved treatment becomes available, untreated patients will soon become rare, further intensifying the need for a rapid, prospective and longitudinal study of the natural history of SMA Type 2 and 3. Here we present the baseline assessments of 81 patients aged 2 to 30 years of which 19 are non-sitter SMA Type 2, 34 are sitter SMA Type 2, 9 non-ambulant SMA Type 3 and 19 ambulant SMA Type 3. Collecting these data at nine sites in France, Germany and Belgium established the feasibility of gathering consistent data from numerous and demanding assessments in a multicenter SMA study. Most assessments discriminated between the four groups well. This included the Motor Function Measure (MFM), pulmonary function testing, strength, electroneuromyography, muscle imaging and workspace volume. Additionally, all of the assessments showed good correlation with the MFM score. As the untreated patient population decreases, having reliable and valid multi-site data will be imperative for recruitment in clinical trials. The pending two-year study results will evaluate the sensitivity of the studied outcomes and biomarkers to disease progression.
ClinicalTrials.gov (NCT02391831).
Missense variants in RNA-binding proteins (RBPs) underlie a spectrum of disease phenotypes, including amyotrophic lateral sclerosis, frontotemporal dementia, and inclusion body myopathy. Here, we ...present ten independent families with a severe, progressive muscular dystrophy, reminiscent of oculopharyngeal muscular dystrophy (OPMD) but of much earlier onset, caused by heterozygous frameshift variants in the RBP hnRNPA2/B1. All disease-causing frameshift mutations abolish the native stop codon and extend the reading frame, creating novel transcripts that escape nonsense-mediated decay and are translated to produce hnRNPA2/B1 protein with the same neomorphic C-terminal sequence. In contrast to previously reported disease-causing missense variants in HNRNPA2B1, these frameshift variants do not increase the propensity of hnRNPA2 protein to fibrillize. Rather, the frameshift variants have reduced affinity for the nuclear import receptor karyopherin β2, resulting in cytoplasmic accumulation of hnRNPA2 protein in cells and in animal models that recapitulate the human pathology. Thus, we expand the phenotypes associated with HNRNPA2B1 to include an early-onset form of OPMD caused by frameshift variants that alter its nucleocytoplasmic transport dynamics.
The aim of this prospective study was to investigate changes in muscle activity during gait in children with Duchenne muscular Dystrophy (DMD). Dynamic surface electromyography recordings (EMGs) of ...16 children with DMD and pathological gait were compared with those of 15 control children. The activity of the rectus femoris (RF), vastus lateralis (VL), medial hamstrings (HS), tibialis anterior (TA) and gastrocnemius soleus (GAS) muscles was recorded and analysed quantitatively and qualitatively. The overall muscle activity in the children with DMD was significantly different from that of the control group. Percentage activation amplitudes of RF, HS and TA were greater throughout the gait cycle in the children with DMD and the timing of GAS activity differed from the control children. Significantly greater muscle coactivation was found in the children with DMD. There were no significant differences between sides. Since the motor command is normal in DMD, the hyper-activity and co-contractions likely compensate for gait instability and muscle weakness, however may have negative consequences on the muscles and may increase the energy cost of gait. Simple rehabilitative strategies such as targeted physical therapies may improve stability and thus the pattern of muscle activity.
Adeno-Associated Virus (AAV) gene therapies are highly promising, such as the onasemnogene abeparvovec (Zolgensma®) in Spinal Muscle Atrophy (SMA). We report the first case of fatal systemic ...Thrombotic MicroAngiopathy (TMA) following onasemnogene abeparvovec in a 6-month-old child with SMA type 1, carrying a potential genetic predisposition in the Complement Factor I gene. Other cases of TMA have recently been reported after onasemnogene abeparvovec, and after AAV9 minidystrophin therapy in the Duchenne muscular dystrophy. The risk-benefit ratio of this therapy must therefore be assessed. Early recognition of TMA and targeted immunotherapy are fundamental to ensure the safety of patients treated with AAV gene therapies.
Dysautonomic symptoms are frequent non-motor complaints in patients with Parkinson’s disease. Numerous neuropathological studies have shown that Lewy bodies and neurites, the pathological hallmarks ...of Parkinson’s disease, are widely distributed throughout the peripheral autonomic nervous systems and across end organs. However, few investigations integrally explored the symptoms and physiology of dysautonomia in Parkinson’s disease. We, therefore, performed a comprehensive evaluation of the autonomic function in a prospective group of 45 patients with idiopathic Parkinson’s disease. Autonomic components (pupillomotor, tear, salivary, cardiovascular, digestive, urinary, sexual, sudomotor functions and skin sensitivity) were evaluated using questionnaires and functional tests. Skin biopsy was performed for intraepidermal nerve fibre density quantification. In addition, all patients underwent polysomnography and a complete neuropsychological and neurological assessment. The analysis association of autonomic components showed that dysautonomic signs and symptoms were heterogeneously distributed among patients. Skin denervation as assessed by intraepidermal nerve fibre density quantification was only associated with quantitative thermal sensory testing (OR = 12.0,
p
= 0.02), constipation (OR = 5.5,
p
= 0.01) and ocular dryness symptoms (OR = 8.29,
p
= 0.04). Cognitive alteration was associated with cardiovascular symptoms (OR = 4.33,
p
= 0.03) and dysfunction (OR = 5.83,
p
= 0.02) as well as with constipation (OR = 5.38,
p
= 0.02). Axial motor impairment and rapid eye movement (REM) sleep behaviour disorder were not related to any of the autonomic complaint or dysfunction. Our results show that autonomic functions are affected in a heterogeneous pattern in Parkinson’s disease, thereby suggesting that the progression of autonomic dysfunction follows an erratic rather than a stepwise progression.
We previously reported that human muscle-derived stem cells (hMuStem cells) contribute to tissue repair after local administration into injured skeletal muscle or infarcted heart in immunodeficient ...rodent models. However, extrapolation of these findings to a clinical context is problematic owing to the considerable differences often seen between in vivo findings in humans versus rodents. Therefore, we investigated whether the muscle regenerative behavior of hMuStem cells is maintained in a clinically relevant transplantation context. Human MuStem cells were intramuscularly administered by high-density microinjection matrices into nonhuman primates receiving tacrolimus-based immunosuppression thereby reproducing the protocol that has so far produced the best results in clinical trials of cell therapy in myopathies. Four and 9 weeks after administration, histological analysis of cell injection sites revealed large numbers of hMuStem cell-derived nuclei in all cases. Most graft-derived nuclei were distributed in small myofiber groups in which no signs of a specific immune response were observed. Importantly, hMuStem cells contributed to simian tissue repair by fusing mainly with host myofibers, demonstrating their capacity for myofiber regeneration in this model. Together, these findings obtained in a valid preclinical model provide new insights supporting the potential of hMuStem cells in future cell therapies for muscle diseases.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a rare, orphan, hereditary neuromuscular disorder with no cure and for which only symptomatic treatment is currently available. A previous phase 2 trial ...has shown preliminary evidence of efficacy for PXT3003 in treating CMT1A. This phase 3, international, randomized, double-blind, placebo-controlled study further investigated the efficacy and safety of high- or low-dose PXT3003 (baclofen/naltrexone/D-sorbitol mg: 6/0.70/210 or 3/0.35/105) in treating subjects with mild to moderate CMT1A.
In this study, 323 subjects with mild-to-moderate CMT1A were randomly assigned in a 1:1:1 ratio to receive 5 mL of high- or low-dose PXT3003, or placebo, orally twice daily for up to 15 months. Efficacy was assessed using the change in Overall Neuropathy Limitations Scale total score from baseline to months 12 and 15 (primary endpoint). Secondary endpoints included the 10-m walk test and other assessments. The high-dose group was discontinued early due to unexpected crystal formation in the high-dose formulation, which resulted in an unanticipated high discontinuation rate, overall and especially in the high-dose group. The statistical analysis plan was adapted to account for the large amount of missing data before database lock, and a modified full analysis set was used in the main analyses. Two sensitivity analyses were performed to check the interpretation based on the use of the modified full analysis set.
High-dose PXT3003 demonstrated significant improvement in the Overall Neuropathy Limitations Scale total score vs placebo (mean difference: - 0.37 points; 97.5% CI - 0.68 to - 0.06; p = 0.008), and consistent treatment effects were shown in the sensitivity analyses. Both PXT3003 doses were safe and well-tolerated.
The high-dose group demonstrated a statistically significant improvement in the primary endpoint and a good safety profile. Overall, high-dose PXT3003 is a promising treatment option for patients with Charcot-Marie-Tooth disease type 1A.
Abstract
Study Objectives
The body-first Parkinson’s disease (PD) hypothesis suggests initial gut Lewy body pathology initially propagates to the pons before reaching the substantia nigra, and ...subsequently progresses to the diencephalic and cortical levels, a disease course presumed to likely occur in PD with rapid eye movement sleep behavior disorder (RBD). We aimed to explore the potential association between colonic phosphorylated alpha-synuclein histopathology (PASH) and diencephalic or cortical dysfunction evidenced by non-rapid eye movement (NREM) sleep and wakefulness polysomnographic markers.
Methods
In a study involving 43 patients with PD who underwent clinical examination, rectosigmoidoscopy, and polysomnography, we detected PASH on colonic biopsies using whole-mount immunostaining. We performed a visual semi-quantitative analysis of NREM sleep and wake electroencephalography (EEG), confirmed it with automated quantification of spindle and slow wave features of NREM sleep, and the wake dominant frequency, and then determined probable Arizona PD stage classifications based on sleep and wake EEG features.
Results
The visual analysis aligned with the automated quantified spindle characteristics and the wake dominant frequency. Altered NREM sleep and wake parameters correlated with markers of PD severity, colonic PASH, and RBD diagnosis. Colonic PASH frequency also increased in parallel to probable Arizona PD stage classifications.
Conclusions
Colonic PASH is strongly associated with widespread brain sleep and wake dysfunction, suggesting an extensive diffusion of the pathologic process in PD. Visual and automated analyses of polysomnography signals provide useful markers to gauge covert brain dysfunction in PD.
Clinical Trial
Name: SYNAPark, URL: https://clinicaltrials.gov/study/NCT01748409, registration: NCT01748409
Graphical Abstract
Graphical Abstract
Duchenne Muscular Dystrophy (DMD) is a neuromuscular disease that inevitably leads to total loss of autonomy. The new therapeutic strategies aim to both improve survival and optimise quality of life. ...Evaluating quality of life is nevertheless a major challenge. No DMD-specific quality of life scale to exists in French. We therefore produced a French translation of the English Duchenne Muscular Dystrophy module of the Pediatric Quality of Life Inventory (PedsQL.sup.TMDMD) following international recommendations. The study objective was to carry out a confirmatory validation of the French version of the PedsQL.sup.TMDMD for paediatric patients with DMD, using French multicentre descriptive cross-sectional data. The sample consisted of 107 patients. Internal consistency was acceptable for proxy-assessments, with Cronbach's alpha coefficients above 0.70, except for the Treatment dimension. For self-assessments, internal consistency was acceptable only for the Daily Activities dimension. Our results showed poor metric qualities for the French version of the PedsQL.sup.TMDMD based on a sample of about 100 children, but these results remained consistent with those of the original validation. This confirms the interest of its use in clinical practice. Keywords: Neuromuscular disorder, Duchenne Muscular Dystrophy, Pediatric Quality of Life (PedsQL)
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