A gait-based paradigm to investigate central body representation in cervical dystonia patients

BACKGROUND

Cervical dystonia (CD) is a common adult-onset idiopathic form of dystonia characterized by an abnormal head posture caused by an excessive activity of the neck muscles. The position of the head is important to direct viewpoint in the rounding environment, and the body orientation, during gait, must be coherent with the subjective straight ahead (SSA). An alteration of the SSA, as in the case of CD patients, could affect gait when visual input is not available. The aim of this study was to probe the behavior of patients with CD during blindfolded walking, investigating the ability to walk straight ahead based only on somatosensory and vestibular information.

METHODS

In this observational cross-sectional study, patients with CD and healthy control subjects (HC) were compared. All participants were evaluated through a gait analysis during blindfolded walking on a GAITRite carpet, relying on their own sense of straightness.

RESULTS

Patients with CD showed lower values of path length (p < 0.001), a lower number of steps on the carpet (p < 0.001). A higher number of CD patients deviated during the task, walking out of the carpet, (p < 0.005) compared to HS. No relation was found between the dystonic side and the gait trajectory deviation. A significant correlation was found between pain symptom and gait performance.

CONCLUSIONS

CD patients showed dysfunctions in controlling dynamic body location during walking without visual afferences, while the dystonic side does not seem to be related to the lateral deviation of the trajectory. Our results would assume that a general proprioceptive impairment could lead to an improper body position awareness in patients with CD.

Agrin loss in Barrett's esophagus-related neoplasia and its utility as a diagnostic and predictive biomarker

PURPOSE

There is an unmet need for identifying novel biomarkers in Barrett's esophagus (BE) that could stratify patients with regards to neoplastic progression. We investigate the expression patterns of extracellular matrix (ECM) molecules in BE and BE-related neoplasia, and assess their value as biomarkers for the diagnosis of BE-related neoplasia and to predict neoplastic progression.

EXPERIMENTAL DESIGN

Gene expression analyses of ECM matrisome gene sets were performed using publicly available data on human BE, BE-related dysplasia, esophageal ADCA and normal esophagus. Immunohistochemical expression of basement membrane (BM) marker agrin (AGRN) and p53 was analyzed in biopsies of BE-related neoplasia from 321 patients in three independent cohorts.

RESULTS

Differential gene expression analysis revealed significant enrichment of ECM matrisome gene sets in dysplastic BE and ADCA compared with controls. Loss of BM AGRN expression was observed in both BE-related dysplasia and ADCA. The mean AGRN loss in BE glands was significantly higher in BErelated dysplasia and ADCA compared to non-dysplastic BE (NDBE; p<0.001; specificity=82.2% and sensitivity=96.4%). Loss of AGRN was significantly higher in NDBE samples from progressors compared to non-progressors (p<0.001) and identified patients who progressed to advanced neoplasia with a specificity of 80.2% and sensitivity of 54.8%. Moreover, the combination of AGRN loss and abnormal p53 staining identified progression to BE-related advanced neoplasia with a specificity and sensitivity of 86.5% and 58.7%.

CONCLUSIONS

We highlight ECM changes during BE progression to neoplasia. BM AGRN loss is a novel diagnostic biomarker that can identify NDBE patients at increased risk of developing advanced neoplasia.

Proteomic Profiling of the ECM of Xenograft Breast Cancer Metastases in Different Organs Reveals Distinct Metastatic Niches

Metastasis causes most cancer-related deaths, and one poorly understood aspect of metastatic cancer is the adaptability of cells from a primary tumor to create new niches and survive in multiple, different secondary sites. We used quantitative mass spectrometry to analyze the extracellular matrix (ECM), a critical component of metastatic niches, in metastases to the brain, lungs, liver, and bone marrow, all derived from parental MDA-MB-231 triple-negative breast cancer cells. Tumor and stromal cells cooperated in forming niches; stromal cells produced predominantly core, structural ECM proteins and tumor cells produced a diverse array of ECM-associated proteins, including secreted factors and modulators of the matrix. In addition, tumor and stromal cells together created distinct niches in each tissue. Downregulation of SERPINB1, a protein elevated in brain metastases, led to a reduction in brain metastasis, suggesting that some niche-specific ECM proteins may be involved in metastatic tropism. SIGNIFICANCE: Tumor and stromal cells together create distinct ECM niches in breast cancer metastases to various tissues, providing new insight into how tumor cells adapt to survive in different tissue environments.

Dual control of pcdh8l/PCNS expression and function in Xenopus laevis neural crest cells by adam13/33 via the transcription factors tfap2α and arid3a

Adam13/33 is a cell surface metalloprotease critical for cranial neural crest (CNC) cell migration. It can cleave multiple substrates including itself, fibronectin, ephrinB, cadherin-11, pcdh8 and pcdh8l (this work). Cleavage of cadherin-11 produces an extracellular fragment that promotes CNC migration. In addition, the adam13 cytoplasmic domain is cleaved by gamma secretase, translocates into the nucleus and regulates multiple genes. Here, we show that adam13 interacts with the arid3a/dril1/Bright transcription factor. This interaction promotes a proteolytic cleavage of arid3a and its translocation to the nucleus where it regulates another transcription factor: tfap2α. Tfap2α in turn activates multiple genes including the protocadherin pcdh8l (PCNS). The proteolytic activity of adam13 is critical for the release of arid3a from the plasma membrane while the cytoplasmic domain appears critical for the cleavage of arid3a. In addition to this transcriptional control of pcdh8l, adam13 cleaves pcdh8l generating an extracellular fragment that also regulates cell migration.

The Italian Dystonia Registry: rationale, design and preliminary findings

The Italian Dystonia Registry is a multicenter data collection system that will prospectively assess the phenomenology and natural history of adult-onset dystonia and will serve as a basis for future etiological, pathophysiological and therapeutic studies. In the first 6 months of activity, 20 movement disorders Italian centres have adhered to the registry and 664 patients have been recruited. Baseline historical information from this cohort provides the first general overview of adult-onset dystonia in Italy. The cohort was characterized by a lower education level than the Italian population, and most patients were employed as artisans, builders, farmers, or unskilled workers. The clinical features of our sample confirmed the peculiar characteristics of adult-onset dystonia, i.e. gender preference, peak age at onset in the sixth decade, predominance of cervical dystonia and blepharospasm over the other focal dystonias, and a tendency to spread to adjacent body parts, The sample also confirmed the association between eye symptoms and blepharospasm, whereas no clear association emerged between extracranial injury and dystonia in a body site. Adult-onset dystonia patients and the Italian population shared similar burden of arterial hypertension, type 2 diabetes, coronary heart disease, dyslipidemia, and hypothyroidism, while hyperthyroidism was more frequent in the dystonia population. Geographic stratification of the study population yielded no major difference in the most clinical and phenomenological features of dystonia. Analysis of baseline information from recruited patients indicates that the Italian Dystonia Registry may be a useful tool to capture the real world clinical practice of physicians that visit dystonia patients.

Evaluation of physical therapy in parkinsonian patients with freezing of gait: a pilot study

Objective: Freezing of gait is a frequently disabling symptom in Parkinson's disease, poorly responding to dopaminergic treatment. We investigated the short-term effectiveness of a rehabilitation protocol in parkinsonian patients with freezing of gait.

Design: Prospective, uncontrolled pilot study with open label design.

Setting: Outpatient service for rehabilitation of neurological disorders.

Subjects: Twelve patients (8 male, 4 female; aged 59-78 years; Hoehn-Yahr stage: 2-3; mean disease duration: 14.29±SD 4.1 years).

Interventions: Patients attended three (45 min) sessions every week, over a six-week period, of physical therapy focused to improve balance, postural control and walking, and to learn new strategies for overcoming freezing of gait.

Main outcome measures: Patients were evaluated before (T0), at the end (T1), and one month after (T2) rehabilitation by means of clinical rating scales (Unified Parkinson Disease Rating Scale-Motor Section; Freezing of Gait Questionnaire; Parkinson Disease Quality of Life Score) and gait parameters (number of strides, stride length and velocity) during a standardized walking test.

Results: The scores of Freezing of Gait Questionnaire and of Parkinson Disease Quality of Life Questionnaire (but not of the Unified Parkinson Disease Rating Scale-Motor Section) were significantly improved after treatment (T1). Gait parameters were significantly improved at T1 and T2.

Conclusions: We showed the potential short-term efficacy of a rehabilitative approach to freezing of gait in Parkinson's disease. The positive outcome was documented by clinical rating scales and objective gait evaluation. The rapid reversibility of the clinical benefit suggests that further studies are needed to better define the optimal frequency and duration of treatment.

Cadherin-11 localizes to focal adhesions and promotes cell-substrate adhesion

Cadherin receptors have a well-established role in cell–cell adhesion, cell polarization and differentiation. However, some cadherins also promote cell and tissue movement during embryonic development and tumour progression. In particular, cadherin-11 is upregulated during tumour and inflammatory cell invasion, but the mechanisms underlying cadherin-11 stimulated cell migration are still incompletely understood. Here, we show that cadherin-11 localizes to focal adhesions and promotes adhesion to fibronectin in Xenopus neural crest, a highly migratory embryonic cell population. Transfected cadherin-11 also localizes to focal adhesions in different mammalian cell lines, while endogenous cadherin-11 shows focal adhesion localization in primary human fibroblasts. In focal adhesions, cadherin-11 co-localizes with β1-integrin and paxillin and physically interacts with the fibronectin-binding proteoglycan syndecan-4. Adhesion to fibronectin mediated by cadherin-11/syndecan-4 complexes requires both the extracellular domain of syndecan-4, and the transmembrane and cytoplasmic domains of cadherin-11. These results reveal an unexpected role of a classical cadherin in cell–matrix adhesion during cell migration.

Cadherins are typically involved in cell-cell adhesion, however cadherin-11 promotes cell migration through an undefined mechanism. Langhe et al. show that cadherin-11 mediates adhesion to the cell matrix at focal adhesions through interaction with syndecan-4.

ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site

The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell-cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo.

A randomized clinical trial to evaluate the effects of rasagiline on depressive symptoms in non-demented Parkinson's disease patients

BACKGROUND AND PURPOSE

Depressed mood is a common psychiatric problem associated with Parkinson's disease (PD), and studies have suggested a benefit of rasagiline treatment.

METHODS

ACCORDO (see the ) was a 12-week, double-blind, placebo-controlled trial to evaluate the effects of rasagiline 1 mg/day on depressive symptoms and cognition in non-demented PD patients with depressive symptoms. The primary efficacy variable was the change from baseline to week 12 in depressive symptoms measured by the Beck Depression Inventory (BDI-IA) total score. Secondary outcomes included change from baseline to week 12 in cognitive function as assessed by a comprehensive neuropsychological battery; Parkinson's disease quality of life questionnaire (PDQ-39) scores; Apathy Scale scores; and Unified Parkinson's Disease Rating Scale (UPDRS) subscores.

RESULTS

One hundred and twenty-three patients were randomized. At week 12 there was no significant difference between groups for the reduction in total BDI-IA score (primary efficacy variable). However, analysis at week 4 did show a significant difference in favour of rasagiline (marginal means difference ± SE: rasagiline -5.46 ± 0.73 vs. placebo -3.22 ± 0.67; P = 0.026). There were no significant differences between groups on any cognitive test. Rasagiline significantly improved UPDRS Parts I (P = 0.03) and II (P = 0.003) scores versus placebo at week 12. Post hoc analyses showed the statistical superiority of rasagiline versus placebo in the UPDRS Part I depression item (P = 0.04) and PDQ-39 mobility (P = 0.007) and cognition domains (P = 0.026).

CONCLUSIONS

Treatment with rasagiline did not have significant effects versus placebo on depressive symptoms or cognition in PD patients with moderate depressive symptoms. Although limited by lack of correction for multiple comparisons, post hoc analyses signalled some improvement in patient-rated cognitive and depression outcomes.

Prevalence and associated features of self-reported freezing of gait in Parkinson disease: The DEEP FOG study

Freezing of Gait (FOG) is a common and disabling symptom in patients with Parkinson disease (PD). The relationship between FOG and dopaminergic medication is complex. The aim of the present study was to estimate the prevalence of self-reported FOG, its associated clinical features, and its relationship with wearing-off in a wide PD population. This is an observational multicenter study of 634 consecutive non-demented PD patients. Patients were identified either as freezers or non-freezers based on item-3 of the Freezing of Gait-Questionnaire. FOG was then classified as on, off and onoff freezing based on its relationship with wearing-off. Patients were assessed with Unified Parkinson's Disease Rating Scale, Hoehn and Yahr scale, 8-item Parkinson's disease Questionnaire, Mini-Mental State Examination. Data from 593 patients were analyzed, 325 (54.3%) were freezers of whom 200 (61.6%) experienced FOG only during off state (off-freezers), 6 (1.8%) only during on state and 119 (36.6%) either in on and off states or independently of dopaminergic response-related symptoms (onoff-freezers). Overall, freezers vs non-freezers had longer disease duration, more advanced disease and greater disability. Moreover, freezers more frequently reported wearing-off and experienced worse quality of life. Onoff-freezers vs off-freezers were older, more severely disabled, less likely to experience wearing-off, treated with lower levodopa equivalent daily dose and with poorer cognitive performance. Self-reported FOG is mainly recognizable in advanced PD and is associated with more disability and worse quality of life. Onoff-FOG may represent the result of under-treatment or rather interpretable as a distinct clinical entity.

The Wnt receptor Frizzled-4 modulates ADAM13 metalloprotease activity

Cranial neural crest (CNC) cells are a transient population of stem cells that originate at the border of the neural plate and the epidermis, and migrate ventrally to contribute to most of the facial structures including bones, cartilage, muscles and ganglia. ADAM13 is a cell surface metalloprotease that is essential for CNC cell migration. Here, we show in Xenopus laevis embryos that the Wnt receptor Fz4 binds to the cysteine-rich domain of ADAM13 and negatively regulates its proteolytic activity in vivo. Gain of Fz4 function inhibits CNC cell migration and can be rescued by gain of ADAM13 function. Loss of Fz4 function also inhibits CNC cell migration and induces a reduction of mature ADAM13, together with an increase in the ADAM13 cytoplasmic fragment that is known to translocate into the nucleus to regulate gene expression. We propose that Fz4 associates with ADAM13 during its transport to the plasma membrane to regulate its proteolytic activity.

GSK3 and Polo-like kinase regulate ADAM13 function during cranial neural crest cell migration

ADAMs are cell surface metalloproteases that control multiple biological processes by cleaving signaling and adhesion molecules. ADAM13 controls cranial neural crest (CNC) cell migration both by cleaving cadherin-11 to release a promigratory extracellular fragment and by controlling expression of multiple genes via its cytoplasmic domain. The latter activity is regulated by γ-secretase cleavage and the translocation of the cytoplasmic domain into the nucleus. One of the genes regulated by ADAM13, the protease calpain8, is essential for CNC migration. Although the nuclear function of ADAM13 is evolutionarily conserved, it is unclear whether the transcriptional regulation is also performed by other ADAMs and how this process may be regulated. We show that ADAM13 function to promote CNC migration is regulated by two phosphorylation events involving GSK3 and Polo-like kinase (Plk). We further show that inhibition of either kinase blocks CNC migration and that the respective phosphomimetic forms of ADAM13 can rescue these inhibitions. However, these phosphorylations are not required for ADAM13 proteolysis of its substrates, γ-secretase cleavage, or nuclear translocation of its cytoplasmic domain. Of significance, migration of the CNC can be restored in the absence of Plk phosphorylation by expression of calpain-8a, pointing to impaired nuclear activity of ADAM13.

ADAM13 function is required in the 3 dimensional context of the embryo during cranial neural crest cell migration in Xenopus laevis

The cranial neural crest (CNC) is a population of cells that arises from the lateral part of the developing brain, migrates ventrally and coordinates the entire craniofacial development of vertebrates. Many molecules are involved in CNC migration including the transmembrane metalloproteases ADAM13 and 19. We have previously shown that these ADAMs cleave a number of extracellular proteins and modify the transcription of a number of genes, and that both of these activities are important for cell migration. Here we show that the knock down of ADAM13 inhibits CNC migration in vivo but not in vitro, indicating that ADAM13 function is required in the 3-dimentional context of the embryo. We further show that the migration of CNC that do not express ADAM13 and ADAM19 can be rescued in vivo by co-grafting wild type CNC. Furthermore, the migration of CNC lacking ADAM13 can be rescued by mechanically separating the CNC from the surrounding ectoderm and mesoderm. Finally, we show that ADAM13 function is autonomous to CNC tissue, as the migration of morphant CNC can only be rescued by ADAM13 expression in the CNC and not the surrounding tissues. Together our results suggest that ADAM13 changes CNC interaction with the extracellular environment and that this change is necessary for their migration in vivo.