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Multiple sclerosis (MS) is a debilitating affliction of the central nervous system (CNS) that involves demyelination of neuronal axons and neurodegeneration resulting in disability that becomes more pronounced in progressive forms of the disease. The involvement of neurodegeneration in MS underscores the need for effective neuroprotective approaches necessitating identification of new therapeutic targets. Herein, we applied an integrated elemental analysis workflow to human MS-affected spinal cord tissue utilising multiple inductively coupled plasma-mass spectrometry methodologies. These analyses revealed shifts in atomic copper as a notable aspect of disease. Complementary gene expression and biochemical analyses demonstrated that changes in copper levels coincided with altered expression of copper handling genes and downstream functionality of cuproenzymes. Copper-related problems observed in the human MS spinal cord were largely reproduced in the experimental autoimmune encephalomyelitis (EAE) mouse model during the acute phase of disease characterised by axonal demyelination, lesion formation, and motor neuron loss. Treatment of EAE mice with the CNS-permeant copper modulating compound CuII(atsm) resulted in recovery of cuproenzyme function, improved myelination and lesion volume, and neuroprotection. These findings support targeting copper perturbations as a therapeutic strategy for MS with CuII(atsm) showing initial promise.
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INTRODUCTION: Early recognition and prompt, appropriate management may reduce mortality in patients with sepsis. The Surviving Sepsis Campaign's guidelines suggest the use of dynamic measurements to guide fluid resuscitation in sepsis; although these methods are rarely employed to monitor cardiac output in response to fluid administration outside intensive care units. This service evaluation investigated the introduction of a nurse led protocolised goal-directed fluid management using a non-invasive cardiac output monitor to the standard assessment of hypotensive ward patients. METHODS: We introduced the use of a goal-directed fluid management protocol into our critical care outreach teams' standard clinical assessment. Forty-nine sequential patients before and thirty-nine after its introduction were included in the assessment. RESULTS: Patients in the post-intervention cohort received less fluid in the 6 h following outreach assessment (750mls vs 1200mls). There were no differences in clinical background or rates of renal replacement therapy, but rates of invasive and non-invasive ventilation were reduced (0% vs 31%). Although the groups were similar, the post-intervention patients had lower recorded blood pressures. CONCLUSION: IV fluid therapy in the patient with hypotension complicating sepsis can be challenging. Excessive IV fluid administration is commonplace and associated with harm, and the use of advanced non-invasive haemodynamic monitoring by trained nurses can provide objective evaluation of individualised response to treatment. Avoiding excessive IV fluid and earlier institution of appropriate vasopressor therapy may improve patient outcomes. IMPLICATIONS FOR CLINICAL PRACTICE: Adoption of dynamic measures of cardiac output outside of critical care by trained critical care nurses is feasible and may translate into improved patient outcomes. In hospitals with a nurse-led critical care outreach service, consideration should be given to such an approach.
Assuntos
Hidratação , Hipotensão , Humanos , Hidratação/métodos , Hidratação/normas , Feminino , Masculino , Pessoa de Meia-Idade , Hipotensão/fisiopatologia , Hipotensão/etiologia , Idoso , Monitorização Fisiológica/métodos , Monitorização Fisiológica/normas , Sepse/complicações , Sepse/fisiopatologia , Cuidados Críticos/métodos , Cuidados Críticos/normas , Estudos de Coortes , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos , Débito Cardíaco/fisiologia , AdultoRESUMO
The copper compound CuII(atsm) has progressed to phase 2/3 testing for treatment of the neurodegenerative disease amyotrophic lateral sclerosis (ALS). CuII(atsm) is neuroprotective in mutant SOD1 mouse models of ALS where its activity is ascribed in part to improving availability of essential copper. However, SOD1 mutations cause only ~ 2% of ALS cases and therapeutic relevance of copper availability in sporadic ALS is unresolved. Herein we assessed spinal cord tissue from human cases of sporadic ALS for copper-related changes. We found that when compared to control cases the natural distribution of spinal cord copper was disrupted in sporadic ALS. A standout feature was decreased copper levels in the ventral grey matter, the primary anatomical site of neuronal loss in ALS. Altered expression of genes involved in copper handling indicated disrupted copper availability, and this was evident in decreased copper-dependent ferroxidase activity despite increased abundance of the ferroxidases ceruloplasmin and hephaestin. Mice expressing mutant SOD1 recapitulate salient features of ALS and the unsatiated requirement for copper in these mice is a biochemical target for CuII(atsm). Our results from human spinal cord indicate a therapeutic mechanism of action for CuII(atsm) involving copper availability may also be pertinent to sporadic cases of ALS.
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Esclerose Lateral Amiotrófica , Complexos de Coordenação , Doenças Neurodegenerativas , Tiossemicarbazonas , Humanos , Camundongos , Animais , Cobre/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Doenças Neurodegenerativas/metabolismo , Camundongos Transgênicos , Medula Espinal/metabolismo , Ceruloplasmina/metabolismo , Modelos Animais de DoençasRESUMO
BACKGROUND: Ferroptosis is a form of regulated cell death characterised by lipid peroxidation as the terminal endpoint and a requirement for iron. Although it protects against cancer and infection, ferroptosis is also implicated in causing neuronal death in degenerative diseases of the central nervous system (CNS). The precise role for ferroptosis in causing neuronal death is yet to be fully resolved. METHODS: To elucidate the role of ferroptosis in neuronal death we utilised co-culture and conditioned medium transfer experiments involving microglia, astrocytes and neurones. We ratified clinical significance of our cell culture findings via assessment of human CNS tissue from cases of the fatal, paralysing neurodegenerative condition of amyotrophic lateral sclerosis (ALS). We utilised the SOD1G37R mouse model of ALS and a CNS-permeant ferroptosis inhibitor to verify pharmacological significance in vivo. RESULTS: We found that sublethal ferroptotic stress selectively affecting microglia triggers an inflammatory cascade that results in non-cell autonomous neuronal death. Central to this cascade is the conversion of astrocytes to a neurotoxic state. We show that spinal cord tissue from human cases of ALS exhibits a signature of ferroptosis that encompasses atomic, molecular and biochemical features. Further, we show the molecular correlation between ferroptosis and neurotoxic astrocytes evident in human ALS-affected spinal cord is recapitulated in the SOD1G37R mouse model where treatment with a CNS-permeant ferroptosis inhibitor, CuII(atsm), ameliorated these markers and was neuroprotective. CONCLUSIONS: By showing that microglia responding to sublethal ferroptotic stress culminates in non-cell autonomous neuronal death, our results implicate microglial ferroptotic stress as a rectifiable cause of neuronal death in neurodegenerative disease. As ferroptosis is currently primarily regarded as an intrinsic cell death phenomenon, these results introduce an entirely new pathophysiological role for ferroptosis in disease.
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Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Camundongos , Animais , Humanos , Microglia/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Superóxido Dismutase-1/metabolismo , Doenças Neurodegenerativas/metabolismo , Morte Celular , Modelos Animais de DoençasRESUMO
Demyelination within the central nervous system (CNS) is a significant feature of debilitating neurological diseases such as multiple sclerosis and administering the copper-selective chelatorcuprizone to mice is widely used to model demyelination in vivo. Conspicuous demyelination within the corpus callosum is generally attributed to cuprizone's ability to restrict copper availability in this vulnerable brain region. However, the small number of studies that have assessed copper in brain tissue from cuprizone-treated mice have produced seemingly conflicting outcomes, leaving the role of CNS copper availability in demyelination unresolved. Herein we describe our assessment of copper concentrations in brain samples from mice treated with cuprizone for 40 d. Importantly, we applied an inductively coupled plasma mass spectrometry methodology that enabled assessment of copper partitioned into soluble and insoluble fractions within distinct brain regions, including the corpus callosum. Our results show that cuprizone-induced demyelination in the corpus callosum was associated with decreased soluble copper in this brain region. Insoluble copper in the corpus callosum was unaffected, as were pools of soluble and insoluble copper in other brain regions. Treatment with the blood-brain barrier permeant copper compound CuII(atsm) increased brain copper levels and this was most pronounced in the soluble fraction of the corpus callosum. This effect was associated with significant mitigation of cuprizone-induced demyelination. These results provide support for the involvement of decreased CNS copper availability in demyelination in the cuprizone model. Relevance to human demyelinating disease is discussed.
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Cuprizona , Doenças Desmielinizantes , Humanos , Animais , Camundongos , Cuprizona/efeitos adversos , Corpo Caloso , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/tratamento farmacológico , Cobre/farmacologia , Oligodendroglia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Bainha de MielinaRESUMO
INTRODUCTION: Population aging longevity and advances in robotic surgery suggest that increasing numbers of older women having gynaeoncological surgery is likely. Postoperative morbidity and mortality are more common in older than younger women with the age-associated characteristics of multimorbidity and frailty being generally predictive of worse outcome. Priorities that inform treatment decisions change during the life course: older patients often place greater' value on quality-of-life-years gained than on life expectancy following cancer treatments. However, data on post-operative cognition, frailty, or functional independence is sparse and not routinely collected. This study aimed to describe the clinical characteristics and trajectory of functional change of older women in the 12 months following gynaeoncological surgery and to explore the associations between them. MATERIALS AND METHODS: The prospective observational cohort study recruited consecutive women aged 65 or over scheduled for major gynaeoncologic surgery between July 2017 and April 2019. Baseline data on cancer stage, multimorbidity, and geriatric syndromes including cognition, frailty, and functional abilities were collected using standardised tools. Delirium and post-operative morbidity were recorded. Post hospital assessments were collected at 3-, 6-, and 12-months. RESULTS: Overall, of 103 eligible participants assessed pre-operatively, most (77, 70%) remained independent in personal care at all assessments from discharge to 12 months. Functional trajectories varied widely over the 12 months but overall there was no significant decline or improvement for the 85 survivors. Eleven experienced a clinically significant decline in function at six months. This was associated with baseline low mood (P < 0.05), albeit with small numbers (6 of 11). Cognitive impairment and frailty were associated with lower baseline function but not with subsequent functional decline. DISCUSSION: There was no clear clinical profile to identify the minority of older adults who experienced a clinically significant decline six months after surgery and for most, the decline was transient. This may be helpful in enabling informed patient consent. Assessment for geriatric syndromes and frailty may improve individual care but our findings do not indicate criteria for segmenting the patient population for selective attention. Future work should focus on causal pathways to potentially avoidable decline in those patients where this is not determined by the cancer itself.