33 research outputs found
Plasma neurofilament heavy chain levels and disease progression in amyotrophic lateral sclerosis: insights from a longitudinal study
Objective To investigate the role of longitudinal
plasma neurofilament heavy chain protein (NfH) levels
as an indicator of clinical progression and survival in
amyotrophic lateral sclerosis (ALS).
Methods A cross-sectional study involving 136
clinically heterogeneous patients with ALS and 104
healthy and neurological controls was extended to
include a prospective analysis of 74 of these ALS cases,
with samplings at approximately 3-month intervals in a
follow-up period of up to 3 years. We analysed the
correlation between longitudinal NfH-phosphoform levels
and disease progression. Temporal patterns of NfH
changes were evaluated using multilevel linear
regression.
Results Baseline plasma NfH levels were higher than
controls only in patients with ALS with short disease
duration to baseline sampling. Compared with controls,
fast-progressing patients with ALS, particularly those
with a short diagnostic latency and disease duration,
had higher plasma NfH levels at an early stage and
lower levels closer to end-stage disease. Lower NfH
levels between visits were associated with rapid
functional deterioration. We also detected antibodies
against NfH, NfH aggregates and NfH cleavage products.
Conclusions Disease progression in ALS involves
defined trajectories of plasma NfH levels, reflecting
speed of neurological decline and survival. Intervisit
plasma NfH changes are also indicative of disease
progression. This study confirms that longitudinal
measurements of NfH plasma levels are more informative
than cross-sectional studies, where the time of sampling
may represent a bias in the interpretation of the results.
Autoantibodies against NfH aggregates and NfH
cleavage products may explain the variable expression of
plasma NfH with disease progressionThis project was funded by The Motor Neurone Disease Association (Malaspina/Apr13/6097) and Barts and The London Charities (468/1714). LG is the Graham Watts Senior Research Fellow, funded by The Brain Research Trust and the European Communityâs Seventh Framework Programme (FP7/2007-2013)
A genome-wide association study of myasthenia gravis
IMPORTANCE: Myasthenia gravis is a chronic, autoimmune, neuromuscular disease characterized by fluctuating weakness of voluntary muscle groups. Although genetic factors are known to play a role in this neuroimmunological condition, the genetic etiology underlying myasthenia gravis is not well understood. OBJECTIVE: To identify genetic variants that alter susceptibility to myasthenia gravis, we performed a genome-wide association study. DESIGN, SETTING, AND PARTICIPANTS: DNA was obtained from 1032 white individuals from North America diagnosed as having acetylcholine receptor antibodyâpositive myasthenia gravis and 1998 race/ethnicity-matched control individuals from January 2010 to January 2011. These samples were genotyped on Illumina OmniExpress single-nucleotide polymorphism arrays. An independent cohort of 423 Italian cases and 467 Italian control individuals were used for replication. MAIN OUTCOMES AND MEASURES: We calculated P values for association between 8114394 genotyped and imputed variants across the genome and risk for developing myasthenia gravis using logistic regression modeling. A threshold P value of 5.0 Ă 10(â8) was set for genome-wide significance after Bonferroni correction for multiple testing. RESULTS: In the over all case-control cohort, we identified association signals at CTLA4 (rs231770; P = 3.98 Ă 10(â8); odds ratio, 1.37; 95% CI, 1.25â1.49), HLA-DQA1 (rs9271871; P = 1.08 Ă 10(â8); odds ratio, 2.31; 95% CI, 2.02 â 2.60), and TNFRSF11A (rs4263037; P = 1.60 Ă 10(â9); odds ratio, 1.41; 95% CI, 1.29â1.53). These findings replicated for CTLA4 and HLA-DQA1 in an independent cohort of Italian cases and control individuals. Further analysis revealed distinct, but overlapping, disease-associated loci for early- and late-onset forms of myasthenia gravis. In the late-onset cases, we identified 2 association peaks: one was located in TNFRSF11A (rs4263037; P = 1.32 Ă 10(â12); odds ratio, 1.56; 95% CI, 1.44â1.68) and the other was detected in the major histocompatibility complex on chromosome 6p21 (HLA-DQA1; rs9271871; P = 7.02 Ă 10(â18); odds ratio, 4.27; 95% CI, 3.92â4.62). Association within the major histocompatibility complex region was also observed in early-onset cases (HLA-DQA1; rs601006; P = 2.52 Ă 10(â11); odds ratio, 4.0; 95% CI, 3.57â4.43), although the set of single-nucleotide polymorphisms was different from that implicated among late-onset cases. CONCLUSIONS AND RELEVANCE: Our genetic data provide insights into aberrant cellular mechanisms responsible for this prototypical autoimmune disorder. They also suggest that clinical trials of immunomodulatory drugs related to CTLA4 and that are already Food and Drug Administration approved as therapies for other autoimmune diseases could be considered for patients with refractory disease
Meta-analysis of pharmacogenetic interactions in amyotrophic lateral sclerosis clinical trials
OBJECTIVE: To assess whether genetic subgroups in recent amyotrophic lateral sclerosis (ALS) trials responded to treatment with lithium carbonate, but that the treatment effect was lost in a large cohort of nonresponders. METHODS: Individual participant data were obtained from 3 randomized trials investigating the efficacy of lithium carbonate. We matched clinical data with data regarding the UNC13A and C9orf72 genotype. Our primary outcome was survival at 12 months. On an exploratory basis, we assessed whether the effect of lithium depended on the genotype. RESULTS: Clinical data were available for 518 of the 606 participants. Overall, treatment with lithium carbonate did not improve 12-month survival (hazard ratio [HR] 1.0, 95% confidence interval [CI] 0.7-1.4; p = 0.96). Both the UNC13A and C9orf72 genotype were independent predictors of survival (HR 2.4, 95% CI 1.3-4.3; p = 0.006 and HR 2.5, 95% CI 1.1-5.2; p = 0.032, respectively). The effect of lithium was different for UNC13A carriers (p = 0.027), but not for C9orf72 carriers (p = 0.22). The 12-month survival probability for UNC13A carriers treated with lithium carbonate improved from 40.1% (95% CI 23.2-69.1) to 69.7% (95% CI 50.4-96.3). CONCLUSIONS: This study incorporated genetic data into past ALS trials to determine treatment effects in a genetic post hoc analysis. Our results suggest that we should reorient our strategies toward finding treatments for ALS, start focusing on genotype-targeted treatments, and standardize genotyping in order to optimize randomization and analysis for future clinical trials
Inhibition of microRNA-210 suppresses pro-inflammatory response and reduces acute brain injury of ischemic stroke in mice
Stroke is a leading cause of mortality and chronic neurologic disability. Yet, the successful treatment remains limited. In this study, we investigated the efficacy and the mechanism of a novel treatment, microRNA-210 (miR-210) inhibition, in protecting acute ischemic brain injury in adult mice. Focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in adult male C57BL/6 mice. MiR-210-LNA (miR-210 inhibitor) or the negative control was administered via intracerebroventricular injection 24h prior or 4h after MCAO. Cerebral infarction volume and behavioral deficits were determined 48h after MCAO. The expression of inflammation-related genes and infiltration/activation of various immune cells in the brain were assessed by RT-qPCR, flow cytometry, and immunohistochemistry. Acute ischemic stroke significantly increased miR-210 levels in the brain, which was abolished by miR-210-LNA administered prior to MCAO. Pre- and post-MCAO treatments with miR-210-LNA significantly decreased cerebral infarction and ameliorated behavioral deficits induced by MCAO. Long-term behavioral recovery was also improved by miR-210-LNA post-treatment. At the same time, inhibition of miR-210 significantly reduced the expression of pro-inflammatory cytokines (TNF-α, IL-1ÎČ, and IL-6) and chemokines (CCL2 and CCL3), but had no significant effect on anti-inflammatory factors (TGF-ÎČ and IL-10). In addition, MCAO-induced macrophage infiltration and microglial activation in the brain were inhibited by the miR-210-LNA treatment. In summary, inhibition of miR-210 suppresses pro-inflammatory response and reduces brain damage in the acute phase of ischemic stroke, providing new insight in molecular basis of a novel therapeutic strategy of miR-210 inhibition in the treatment of acute ischemic stroke
Analysis of amyotrophic lateral sclerosis as a multistep process: a population-based modelling study
BACKGROUND
Amyotrophic lateral sclerosis shares characteristics with some cancers, such as onset being more common in later life, progression usually being rapid, the disease affecting a particular cell type, and showing complex inheritance. We used a model originally applied to cancer epidemiology to investigate the hypothesis that amyotrophic lateral sclerosis is a multistep process.
METHODS
We generated incidence data by age and sex from amyotrophic lateral sclerosis population registers in Ireland (registration dates 1995-2012), the Netherlands (2006-12), Italy (1995-2004), Scotland (1989-98), and England (2002-09), and calculated age and sex-adjusted incidences for each register. We regressed the log of age-specific incidence against the log of age with least squares regression. We did the analyses within each register, and also did a combined analysis, adjusting for register.
FINDINGS
We identified 6274 cases of amyotrophic lateral sclerosis from a catchment population of about 34 million people. We noted a linear relationship between log incidence and log age in all five registers: England r(2)=0·95, Ireland r(2)=0·99, Italy r(2)=0·95, the Netherlands r(2)=0·99, and Scotland r(2)=0·97; overall r(2)=0·99. All five registers gave similar estimates of the linear slope ranging from 4·5 to 5·1, with overlapping confidence intervals. The combination of all five registers gave an overall slope of 4·8 (95% CI 4·5-5·0), with similar estimates for men (4·6, 4·3-4·9) and women (5·0, 4·5-5·5).
INTERPRETATION
A linear relationship between the log incidence and log age of onset of amyotrophic lateral sclerosis is consistent with a multistage model of disease. The slope estimate suggests that amyotrophic lateral sclerosis is a six-step process. Identification of these steps could lead to preventive and therapeutic avenues.
FUNDING
UK Medical Research Council; UK Economic and Social Research Council; Ireland Health Research Board; The Netherlands Organisation for Health Research and Development (ZonMw); the Ministry of Health and Ministry of Education, University, and Research in Italy; the Motor Neurone Disease Association of England, Wales, and Northern Ireland; and the European Commission (Seventh Framework Programme)
Dying with motor neurone disease, what can we learn from family caregivers?
Backgroundâ Increasingly, people with neurodegenerative illness are cared for at home until close to death. Yet, discussing the reality of dying remains a social taboo. Objectiveâ To examine the ways, family caregivers of people living with motor neurone disease (MND) experienced the dying of their relative and to identify how health practitioners can better prepare families for endâofâlife care. Designâ Secondary analysis was undertaken on data sets generated from two longitudinal qualitative studies employing similar data collection and analysis methods. Combining data sets increased participant numbers in a low incidence disease group. Setting and participantsâ Primary studies were undertaken with family caregivers in England and Australia. Interview and observational data were collected mostly in home. Participants who discussed dying and death formed the sample for secondary analysis. Resultsâ Combined data revealed four major themes: planning for end of life, unexpected dying, dignity in the dying body and positive end to MND. Despite short survival predictions, discussions among family members about dying were often sporadic and linked to loss of hope. Effective planning for death assisted caregivers to manage the final degenerative processes of dying. When plans were not effectively communicated or enacted, capacity to preserve personhood was reduced. Discussion and Conclusionâ Returning death and dying to social discourse will raise the level of community awareness and normalize conversations about endâofâlife care. Strategies for onâgoing, effective communication that facilitates advance care planning among patients, their families and practitioners are essential to improve dying and death for people with MND and their family caregivers
NRF2 Promotes Tumor Maintenance by Modulating mRNA Translation in Pancreatic Cancer
Summary Pancreatic cancer is a deadly malignancy that lacks effective therapeutics. We previously reported that oncogenic Kras induced the redox master regulator Nfe2l2/Nrf2 to stimulate pancreatic and lung cancer initiation. Here, we show that NRF2 is necessary to maintain pancreatic cancer proliferation by regulating mRNA translation. Specifically, loss of NRF2 led to defects in autocrine epidermal growth factor receptor (EGFR) signaling and oxidation of specific translational regulatory proteins, resulting in impaired cap-dependent and cap-independent mRNA translation in pancreatic cancer cells. Combined targeting of the EGFR effector AKT and the glutathione antioxidant pathway mimicked Nrf2 ablation to potently inhibit pancreatic cancer ex vivo and in vivo, representing a promising synthetic lethal strategy for treating the disease