scholarly journals Characterization of Fluid Biomarkers Reveals Lysosome Dysfunction and Neurodegeneration in Neuronopathic MPS II Patients

2020 ◽  
Vol 21 (15) ◽  
pp. 5188 ◽  
Author(s):  
Akhil Bhalla ◽  
Ritesh Ravi ◽  
Meng Fang ◽  
Annie Arguello ◽  
Sonnet S. Davis ◽  
...  
Keyword(s):  
Neuronal Damage ◽  
Lysosomal Storage ◽  
Mucopolysaccharidosis Type Ii ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
Mps Ii ◽  
Cellular Dysfunction ◽  
The Relationship ◽  
The Brain

Mucopolysaccharidosis type II is a lysosomal storage disorder caused by a deficiency of iduronate-2-sulfatase (IDS) and characterized by the accumulation of the primary storage substrate, glycosaminoglycans (GAGs). Understanding central nervous system (CNS) pathophysiology in neuronopathic MPS II (nMPS II) has been hindered by the lack of CNS biomarkers. Characterization of fluid biomarkers has been largely focused on evaluating GAGs in cerebrospinal fluid (CSF) and the periphery; however, GAG levels alone do not accurately reflect the broad cellular dysfunction in the brains of MPS II patients. We utilized a preclinical mouse model of MPS II, treated with a brain penetrant form of IDS (ETV:IDS) to establish the relationship between markers of primary storage and downstream pathway biomarkers in the brain and CSF. We extended the characterization of pathway and neurodegeneration biomarkers to nMPS II patient samples. In addition to the accumulation of CSF GAGs, nMPS II patients show elevated levels of lysosomal lipids, neurofilament light chain, and other biomarkers of neuronal damage and degeneration. Furthermore, we find that these biomarkers of downstream pathology are tightly correlated with heparan sulfate. Exploration of the responsiveness of not only CSF GAGs but also pathway and disease-relevant biomarkers during drug development will be crucial for monitoring disease progression, and the development of effective therapies for nMPS II.

scholarly journals Haemoglobin causes neuronal damage in vivo which is preventable by haptoglobin

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Patrick Garland ◽  
Matthew J Morton ◽  
William Haskins ◽  
Ardalan Zolnourian ◽  
Andrew Durnford ◽  
...  
Keyword(s):  
Subarachnoid Haemorrhage ◽  
Prolonged Exposure ◽  
Neuronal Damage ◽  
Clinical Importance ◽  
Large Vessel ◽  
Therapeutic Window ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
The Brain

Abstract After subarachnoid haemorrhage, prolonged exposure to toxic extracellular haemoglobin occurs in the brain. Here, we investigate the role of haemoglobin neurotoxicity in vivo and its prevention. In humans after subarachnoid haemorrhage, haemoglobin in cerebrospinal fluid was associated with neurofilament light chain, a marker of neuronal damage. Most haemoglobin was not complexed with haptoglobin, an endogenous haemoglobin scavenger present at very low concentration in the brain. Exogenously added haptoglobin bound most uncomplexed haemoglobin, in the first 2 weeks after human subarachnoid haemorrhage, indicating a wide therapeutic window. In mice, the behavioural, vascular, cellular and molecular changes seen after human subarachnoid haemorrhage were recapitulated by modelling a single aspect of subarachnoid haemorrhage: prolonged intrathecal exposure to haemoglobin. Haemoglobin-induced behavioural deficits and astrocytic, microglial and synaptic changes were attenuated by haptoglobin. Haptoglobin treatment did not attenuate large-vessel vasospasm, yet improved clinical outcome by restricting diffusion of haemoglobin into the parenchyma and reducing small-vessel vasospasm. In summary, haemoglobin toxicity is of clinical importance and preventable by haptoglobin, independent of large-vessel vasospasm.

CSF chitinase 3-like 1 is associated with iron rims in patients with a first demyelinating event

2021 ◽  
pp. 135245852110100
Author(s):  
Manuel Comabella ◽  
Margareta A Clarke ◽  
Sabine Schaedelin ◽  
Mar Tintoré ◽  
Deborah Pareto ◽  
...  
Keyword(s):  
Single Molecule ◽  
Multivariable Analysis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Lesion Volume ◽  
Univariable Analysis ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
Multivariable Analyses ◽  
Prognostic Implications ◽  
The Relationship

Background: Chronic active lesions with iron rims have prognostic implications in patients with multiple sclerosis. Objective: To assess the relationship between iron rims and levels of chitinase 3-like 1 (CHI3L1), neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) in patients with a first demyelinating event. Methods: Iron rims were identified using 3T susceptibility-weighted imaging. Serum NfL and GFAP levels were measured by single-molecule array assays. CSF (cerebrospinal fluid) CHI3L1 levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: Sixty-one patients were included in the study. The presence of iron rims was associated with higher T2 lesion volume and higher number of gadolinium-enhancing lesions. In univariable analysis, having ⩾2 iron rims (vs 0) was associated with increased CSF CHI3L1 levels (β = 1.41; 95% confidence interval (CI) = 1.10–1.79; p < 0.01) and serum NfL levels (β = 2.30; 95% CI = 1.47–3.60; p < 0.01). In multivariable analysis, however, only CSF CHI3L1 levels remained significantly associated with the presence of iron rim lesions (β = 1.45; 95% CI = 1.11–1.90; p < 0.01). The presence of ⩾2 iron rims was not associated with increased serum GFAP levels in univariable or multivariable analyses. Conclusion: These findings support an important contribution of activated microglia/macrophages to the pathophysiology of chronic active lesions with iron rims in patients with a first demyelinating event.

scholarly journals No evidence of neuronal damage as measured by neurofilament light chain in a HIV cure study utilising a kick-and-kill approach

2021 ◽  
pp. 100056
Author(s):  
Jasmini ALAGARATNAM ◽  
Wolfgang STÖHR ◽  
Jamie TOOMBS ◽  
Amanda HESLEGRAVE ◽  
Henrik ZETTERBERG ◽  
...  
Keyword(s):  
Light Chain ◽  
Neuronal Damage ◽  
Hiv Cure ◽  
Neurofilament Light Chain ◽  
Neurofilament Light

scholarly journals Should We Use Clinical Tools to Identify Disease Progression?

2021 ◽  
Vol 11 ◽  
Author(s):  
Hernan Inojosa ◽  
Undine Proschmann ◽  
Katja Akgün ◽  
Tjalf Ziemssen
Keyword(s):  
Multiple Sclerosis ◽  
Clinical Markers ◽  
Disability Progression ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
Secondary Progressive ◽  
Disability Status ◽  
Relapsing Remitting ◽  
Clinical Tools

The presence of disability progression in multiple sclerosis (MS) is an important hallmark for MS patients in the course of their disease. The transition from relapsing remitting (RRMS) to secondary progressive forms of the disease (SPMS) represents a significant change in their quality of life and perception of the disease. It could also be a therapeutic key for opportunities, where approaches different from those in the initial phases of the disease can be adopted. The characterization of structural biomarkers (e.g., magnetic resonance imaging or neurofilament light chain) has been proposed to differentiate between both phenotypes. However, there is no definite threshold between them. Whether the risk of clinical progression can be predicted by structural markers at early disease phases is still a focus of clinical research. However, several theories and pathological evidence suggest that both disease phenotypes are part of a continuum with common pathophysiological mechanisms. In this case, the clinical evaluation of the patients would play a preponderant role above destruction biomarkers for the early identification of disability progression and SPMS. For this purpose, the use of clinical tools beyond the Expanded Disability Status Scale (EDSS) should be considered. Besides established functional tests such as the Multiple Sclerosis Functional Composite (MSFC), patient's neurological history or digital resources may help neurologists in the decision-taking. In this article, we discuss arguments for the use of clinical markers in the detection of secondary progressive MS and the characterization of progressive disease activity.

scholarly journals Modeling Mucopolysaccharidosis Type II in the Fruit Fly by Using the RNA Interference Approach

Life ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 263
Author(s):  
Laura Rigon ◽  
Nicole Kucharowski ◽  
Franka Eckardt ◽  
Reinhard Bauer
Keyword(s):  
Rna Interference ◽  
Enzymatic Activity ◽  
Dermatan Sulfate ◽  
Fruit Fly ◽  
Neurological Involvement ◽  
Mucopolysaccharidosis Type ◽  
Type Ii ◽  
Lysosomal Storage ◽  
Mucopolysaccharidosis Type Ii ◽  
Mps Ii

Mucopolysaccharidosis type II (MPS II) is a lysosomal storage disorder that occurs due to the deficit of the lysosomal enzyme iduronate 2-sulfatase (IDS) that leads to the storage of the glycosaminoglycan heparan- and dermatan-sulfate in all organs and tissues. It is characterized by important clinical features and the severe form presents with a heavy neurological involvement. However, almost nothing is known about the neuropathogenesis of MPS II. To address this issue, we developed a ubiquitous, neuronal, and glial-specific knockdown model in Drosophila melanogaster by using the RNA interference (RNAi) approach. Knockdown of the Ids/CG12014 gene resulted in a significant reduction of the Ids gene expression and enzymatic activity. However, glycosaminoglycan storage, survival, molecular markers (Atg8a, Lamp1, Rab11), and locomotion behavior were not affected. Even strongly reduced, IDS-activity was enough to prevent a pathological phenotype in a MPS II RNAi fruit fly. Thus, a Drosophila MPS II model requires complete abolishment of the enzymatic activity.

scholarly journals Evaluation of neurofilament light chain in the cerebrospinal fluid and blood as a biomarker for neuronal damage in experimental pneumococcal meningitis

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Ngoc Dung Le ◽  
Lukas Muri ◽  
Denis Grandgirard ◽  
Jens Kuhle ◽  
David Leppert ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Single Molecule ◽  
Light Chain ◽  
Pneumococcal Meningitis ◽  
Neuronal Damage ◽  
Neuronal Injury ◽  
Health Concern ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
Inflammatory Phase

Abstract Background Pneumococcal meningitis (PM) remains a global public health concern and affects all age groups. If acquired during infancy or childhood, permanent neurofunctional deficits including cognitive impairment, cerebral palsy, and secondary epilepsy are typical sequelae of neuronal injury. Determination of patients at risk for the development of brain injury and subsequent neurofunctional sequelae could help to identify patients for focused management. Neurofilament light chain (NfL) is an axonal cytoskeletal protein released upon neuronal injury into the cerebrospinal fluid (CSF) and blood. As little is known about the course of neurofilament release in the course of PM, we measured CSF and serum NfL levels longitudinally in experimental PM (ePM). Methods Eleven-day-old infant Wistar rats were infected intracisternally with Streptococcus pneumoniae and treated with ceftriaxone. At 18 and 42 h post-infection (hpi), the blood and CSF were sampled for NfL measurements by a single molecule array technology. Inflammatory cytokines and MMP-9 in CSF were quantified by magnetic bead multiplex assay (Luminex®) and by gel zymography, respectively. Results In ePM, CSF and serum NfL levels started to increase at 18 hpi and were 26- and 3.5-fold increased, respectively, compared to mock-infected animals at 42 hpi (p < 0.0001). CSF and serum NfL correlated at 18 hpi (p < 0.05, r = 0.4716) and 42 hpi (p < 0.0001, r = 0.8179). Both CSF and serum NfL at 42 hpi strongly correlated with CSF levels of IL-1β, TNF-α, and IL-6 and of MMP-9 depending on their individual kinetics. Conclusion Current results demonstrate that during the peak inflammatory phase of ePM, NfL levels in CSF and serum are the highest among CNS disease models studied so far. Given the strong correlation of CSF versus serum NfL, and its CNS-specific signal character, longitudinal measurements to monitor the course of PM could be performed based on blood sample tests, i.e., without the need of repetitive spinal taps. We conclude that NfL in the serum should be evaluated as a biomarker in PM.

scholarly journals If the skull fits: magnetic resonance imaging and microcomputed tomography for combined analysis of brain and skull phenotypes in the mouse

2012 ◽  
Vol 44 (20) ◽  
pp. 992-1002 ◽  
Author(s):  
Brian J. Nieman ◽  
Marissa C. Blank ◽  
Brian B. Roman ◽  
R. Mark Henkelman ◽  
Kathleen J. Millen
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Prognostic Significance ◽  
Microcomputed Tomography ◽  
Complete Characterization ◽  
Mammalian Brain ◽  
Resonance Imaging ◽  
The Relationship ◽  
The Brain

The mammalian brain and skull develop concurrently in a coordinated manner, consistently producing a brain and skull that fit tightly together. It is common that abnormalities in one are associated with related abnormalities in the other. However, this is not always the case. A complete characterization of the relationship between brain and skull phenotypes is necessary to understand the mechanisms that cause them to be coordinated or divergent and to provide perspective on the potential diagnostic or prognostic significance of brain and skull phenotypes. We demonstrate the combined use of magnetic resonance imaging and microcomputed tomography for analysis of brain and skull phenotypes in the mouse. Co-registration of brain and skull images allows comparison of the relationship between phenotypes in the brain and those in the skull. We observe a close fit between the brain and skull of two genetic mouse models that both show abnormal brain and skull phenotypes. Application of these three-dimensional image analyses in a broader range of mouse mutants will provide a map of the relationships between brain and skull phenotypes generally and allow characterization of patterns of similarities and differences.

scholarly journals Plasma neurofilament light chain protein is not increased in treatment-resistant schizophrenia and first-degree relatives

2021 ◽  
pp. 000486742110586
Author(s):  
Dhamidhu Eratne ◽  
Shorena Janelidze ◽  
Charles B Malpas ◽  
Samantha Loi ◽  
Mark Walterfang ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Light Chain ◽  
Neurodegenerative Disorders ◽  
Neuronal Damage ◽  
First Episode ◽  
Treatment Resistant ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
First Degree Relatives ◽  
Frontotemporal Dementias

Objective: Schizophrenia, a complex psychiatric disorder, is often associated with cognitive, neurological and neuroimaging abnormalities. The processes underlying these abnormalities, and whether a subset of people with schizophrenia have a neuroprogressive or neurodegenerative component to schizophrenia, remain largely unknown. Examining fluid biomarkers of diverse types of neuronal damage could increase our understanding of these processes, as well as potentially provide clinically useful biomarkers, for example with assisting with differentiation from progressive neurodegenerative disorders such as Alzheimer and frontotemporal dementias. Methods: This study measured plasma neurofilament light chain protein (NfL) using ultrasensitive Simoa technology, to investigate the degree of neuronal injury in a well-characterised cohort of people with treatment-resistant schizophrenia on clozapine ( n = 82), compared to first-degree relatives (an at-risk group, n = 37), people with schizophrenia not treated with clozapine ( n = 13), and age- and sex-matched controls ( n = 59). Results: We found no differences in NfL levels between treatment-resistant schizophrenia (mean NfL, M = 6.3 pg/mL, 95% confidence interval: [5.5, 7.2]), first-degree relatives (siblings, M = 6.7 pg/mL, 95% confidence interval: [5.2, 8.2]; parents, M after adjusting for age = 6.7 pg/mL, 95% confidence interval: [4.7, 8.8]), controls (M = 5.8 pg/mL, 95% confidence interval: [5.3, 6.3]) and not treated with clozapine (M = 4.9 pg/mL, 95% confidence interval: [4.0, 5.8]). Exploratory, hypothesis-generating analyses found weak correlations in treatment-resistant schizophrenia, between NfL and clozapine levels (Spearman’s r = 0.258, 95% confidence interval: [0.034, 0.457]), dyslipidaemia ( r = 0.280, 95% confidence interval: [0.064, 0.470]) and a negative correlation with weight ( r = −0.305, 95% confidence interval: [−0.504, −0.076]). Conclusion: Treatment-resistant schizophrenia does not appear to be associated with neuronal, particularly axonal degeneration. Further studies are warranted to investigate the utility of NfL to differentiate treatment-resistant schizophrenia from neurodegenerative disorders such as behavioural variant frontotemporal dementia, and to explore NfL in other stages of schizophrenia such as the prodome and first episode.

scholarly journals Newborn Screening for Mucopolysaccharidosis Type II in Illinois: An Update

2020 ◽  
Vol 6 (3) ◽  
pp. 73 ◽  
Author(s):  
Barbara K. Burton ◽  
Rachel Hickey ◽  
Lauren Hitchins
Keyword(s):  
Newborn Screening ◽  
Early Years ◽  
Mucopolysaccharidosis Type ◽  
Type Ii ◽  
Lysosomal Storage ◽  
Mucopolysaccharidosis Type Ii ◽  
Effective Treatment Option ◽  
Positive Screen ◽  
Enzyme Replacement ◽  
Mps Ii

Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is a rare, progressive multisystemic lysosomal storage disorder with significant morbidity and premature mortality. Infants with MPS II develop signs and symptoms of the disorder in the early years of life, yet diagnostic delays are very common. Enzyme replacement therapy is an effective treatment option. It has been shown to prolong survival and improve or stabilize many somatic manifestations of the disorder. Our initial experience with newborn screening in 162,000 infants was previously reported. Here, we update that experience with the findings in 339,269 infants. Measurement of iduronate-2-sulfatase (I2S) activity was performed on dried blood spot samples submitted for other newborn screening disorders. A positive screen was defined as I2S activity less than or equal to 10% of the daily median. In this series, 28 infants had a positive screening test result, and four other infants had a borderline result. Three positive diagnoses of MPS II were established, and 25 were diagnosed as having I2S pseudodeficiency. The natural history and the clinical features of MPS II make it an ideal target for newborn screening. Newborn screening was effective in identifying affected infants in our population with an acceptable rate of false positive results.

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