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1.
J Neuroinflammation ; 21(1): 77, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539253

RESUMO

Adiponectin (APN) is an adipokine which predominantly expresses in adipocytes with neuroprotective and anti-inflammatory effects. We have recently indicated that circulatory trimeric APN can enter the brain by crossing the blood-brain barrier (BBB) and modulate microglia-mediated neuroinflammation. Here, we found that the microglial NLR family pyrin domain containing 3 (NLRP3)-inflammasome activation was exacerbated in APN-/-5xFAD mice in age-dependent manner. The focus of this study was to develop a new and tractable therapeutic approach for treating Alzheimer's disease (AD)-related pathology in 5xFAD mice using peripheral APN gene therapy. We have generated and transduced adeno-associated virus (AAV2/8) expressing the mouse mutated APN gene (APNC39S) into the liver of 5xFAD mice that generated only low-molecular-weight trimeric APN (APNTri). Single dose of AAV2/8-APNC39S in the liver increased circulatory and cerebral APN levels indicating the overexpressed APNTri was able to cross the BBB. Overexpression of APNTri decreased both the soluble and fibrillar Aß in the brains of 5xFAD mice. AAV2/8-APNTri treatment reduced Aß-induced IL-1ß and IL-18 secretion by suppressing microglial NLRP3-inflammasome activation. The memory functions improved significantly in AAV-APNTri-treated 5xFAD mice with reduction of dystrophic neurites. These findings demonstrate that peripheral gene delivery to overexpress trimeric APN can be a potential therapy for AD.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/terapia , Doença de Alzheimer/patologia , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Adiponectina/genética , Adiponectina/farmacologia , Microglia , Fígado/patologia , Peptídeos beta-Amiloides/farmacologia
2.
Int J Stroke ; : 17474930241239523, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38429252

RESUMO

BACKGROUND: Recent intensive low-density lipoprotein cholesterol (LDL-C) lowering trials, including FOURIER, ODYSSEY OUTCOMES, and Treat Stroke to Target (TST) trials, have mostly refuted the concern surrounding statin use, LDL-C lowering, and intracerebral hemorrhage (ICH) risk. However, the results from these trials may not be fully applied to ICH survivors, as the populations studied were mainly patients without prior ICH, in whom the inherent ICH risk is more than 10 times lower than that of ICH survivors. Although available literature on statin use after ICH has demonstrated no excess risk of recurrent ICH, other potential factors that may modify ICH risk, especially hypertension control and ICH etiology, have not generally been considered. Notably, data on LDL-C levels following ICH are lacking. AIMS: We aim to investigate the association between LDL-C levels and statin use with ICH risk among ICH survivors, and to determine whether the risk differed with patients' characteristics, especially ICH etiology. METHODS: Follow-up data of consecutive spontaneous ICH survivors enrolled in the University of Hong Kong prospective stroke registry from 2011 to 2019 were retrospectively analyzed. ICH etiology was classified as cerebral amyloid angiopathy (CAA) using the modified Boston criteria or hypertensive arteriopathy, while the mean follow-up LDL-C value was categorized as <1.8 or ⩾1.8 mmol/L. The primary endpoint was recurrent ICH. The association of LDL-C level and statin use with recurrent ICH was determined using multivariable Cox regression. Pre-specified subgroup analyses were performed, including based on ICH etiology and statin prescription. Follow-up blood pressure was included in all the regression models. RESULTS: In 502 ICH survivors (mean age = 64.2 ± 13.5 years, mean follow-up LDL-C = 2.2 ± 0.6 mmol/L, 28% with LDL-C <1.8 mmol/L), 44 had ICH recurrence during a mean follow-up of 5.9 ± 2.8 years. Statin use after ICH was not associated with recurrent ICH (adjusted hazard ratio (AHR) = 1.07, 95% confidence interval (CI) = 0.57-2.00). The risk of ICH recurrence was increased for follow-up LDL-C <1.8 mmol/L (AHR = 1.99, 95% CI = 1.06-3.73). This association was predominantly observed in ICH attributable to CAA (AHR = 2.52, 95% CI = 1.06-5.99) and non-statin users (AHR = 2.91, 95% CI = 1.08-7.86). CONCLUSION: The association between post-ICH LDL-C <1.8 mmol/L and recurrent ICH was predominantly observed in CAA patients and those with intrinsically low LDL-C (non-statin users). While statins can be safely prescribed in ICH survivors, LDL-C targets should be individualized and caution must be exercised in CAA patients.

3.
AJNR Am J Neuroradiol ; 45(3): 305-311, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38302198

RESUMO

BACKGROUND AND PURPOSE: DTI can be used to derive conventional diffusion measurements, which can measure WM abnormalities in multiple sclerosis. DTI can also be used to construct structural brain networks and derive network measurements. However, few studies have compared their sensitivity in detecting brain alterations, especially in longitudinal studies. Therefore, in this study, we aimed to determine which type of measurement is more sensitive in tracking the dynamic changes over time in MS. MATERIALS AND METHODS: Eighteen patients with MS were recruited at baseline and followed up at 6 and 12 months. All patients underwent MR imaging and clinical evaluation at 3 time points. Diffusion and network measurements were derived, and their brain changes were evaluated. RESULTS: None of the conventional DTI measurements displayed statistically significant changes during the follow-up period; however, the nodal degree, nodal efficiency, and nodal path length of the left middle frontal gyrus and bilateral inferior frontal gyrus, opercular part showed significant longitudinal changes between baseline and at 12 months, respectively. CONCLUSIONS: The nodal degree, nodal efficiency, and nodal path length of the left middle frontal gyrus and bilateral inferior frontal gyrus, opercular part may be used to monitor brain changes over time in MS.


Assuntos
Esclerose Múltipla , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Esclerose Múltipla/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Córtex Pré-Frontal
4.
Pharmaceutics ; 16(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38258130

RESUMO

Multiple sclerosis is an important neurological disease affecting millions of young patients globally. It is encouraging that more than ten disease-modifying drugs became available for use in the past two decades. These disease-modifying therapies (DMTs) have different levels of efficacy, routes of administration, adverse effect profiles and concerns for pregnancy. Much knowledge and caution are needed for their appropriate use in MS patients who are heterogeneous in clinical features and severity, lesion load on magnetic resonance imaging and response to DMT. We aim for an updated review of the concept of personalization in the use of DMT for relapsing MS patients. Shared decision making with consideration for the preference and expectation of patients who understand the potential efficacy/benefits and risks of DMT is advocated.

5.
Brain Sci ; 13(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37508945

RESUMO

Background: Olfactory dysfunction (OD) is a common neurosensory manifestation in long COVID. An effective and safe treatment against COVID-19-related OD is needed. Methods: This pilot trial recruited long COVID patients with persistent OD. Participants were randomly assigned to receive short-course (14 days) oral vitamin A (VitA; 25,000 IU per day) and aerosolised diffuser olfactory training (OT) thrice daily (combination), OT alone (standard care), or observation (control) for 4 weeks. The primary outcome was differences in olfactory function by butanol threshold tests (BTT) between baseline and end-of-treatment. Secondary outcomes included smell identification tests (SIT), structural MRI brain, and serial seed-based functional connectivity (FC) analyses in the olfactory cortical network by resting-state functional MRI (rs-fMRI). Results: A total of 24 participants were randomly assigned to receive either combination treatment (n = 10), standard care (n = 9), or control (n = 5). Median OD duration was 157 days (IQR 127-175). Mean baseline BTT score was 2.3 (SD 1.1). At end-of-treatment, mean BTT scores were significantly higher for the combination group than control (p < 0.001, MD = 4.4, 95% CI 1.7 to 7.2) and standard care (p = 0.009) groups. Interval SIT scores increased significantly (p = 0.009) in the combination group. rs-fMRI showed significantly higher FC in the combination group when compared to other groups. At end-of-treatment, positive correlations were found in the increased FC at left inferior frontal gyrus and clinically significant improvements in measured BTT (r = 0.858, p < 0.001) and SIT (r = 0.548, p = 0.042) scores for the combination group. Conclusions: Short-course oral VitA and aerosolised diffuser OT was effective as a combination treatment for persistent OD in long COVID.

6.
Brain Sci ; 13(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37190560

RESUMO

Structural and diffusion kurtosis imaging (DKI) can be used to assess hippocampal macrostructural and microstructural alterations respectively, in Alzheimer's disease (AD) spectrum, spanning from subjective cognitive decline (SCD) to mild cognitive impairment (MCI) and AD. In this study, we explored the diagnostic performance of structural imaging and DKI of the hippocampus in the AD spectrum. Eleven SCD, thirty-seven MCI, sixteen AD, and nineteen age- and sex-matched normal controls (NCs) were included. Bilateral hippocampal volume, mean diffusivity (MD), and mean kurtosis (MK) were obtained. We detected that in AD vs. NCs, the right hippocampal volume showed the most prominent AUC value (AUC = 0.977); in MCI vs. NCs, the right hippocampal MD was the most sensitive discriminator (AUC = 0.819); in SCD vs. NCs, the left hippocampal MK was the most sensitive biomarker (AUC = 0.775). These findings suggest that, in the predementia stage (SCD and MCI), hippocampal microstructural changes are predominant, and the best discriminators are microstructural measurements (left hippocampal MK for SCD and right hippocampal MD for MCI); while in the dementia stage (AD), hippocampal macrostructural alterations are superior, and the best indicator is the macrostructural index (right hippocampal volume).

7.
Stroke ; 54(6): 1548-1557, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37216445

RESUMO

BACKGROUND: Major intracerebral hemorrhage (ICH) trials have largely been unable to demonstrate therapeutic benefit in improving functional outcomes. This may be partly due to the heterogeneity of ICH outcomes based on their location, where a small strategic ICH could be debilitating, thus confounding therapeutic effects. We aimed to determine the ideal hematoma volume cutoff for different ICH locations in predicting ICH outcomes. METHODS: We retrospectively analyzed consecutive ICH patients enrolled in the University of Hong Kong prospective stroke registry from January 2011 to December 2018. Patients with premorbid modified Rankin Scale score >2 or who underwent neurosurgical intervention were excluded. ICH volume cutoff, sensitivity, and specificity in predicting respective 6-month neurological outcomes (good [modified Rankin Scale score 0-2], poor [modified Rankin Scale score 4-6], and mortality) for specific ICH locations were determined using receiver operating characteristic curves. Separate multivariate logistic regression models were also conducted for each location-specific volume cutoff to determine whether these cutoffs were independently associated with respective outcomes. RESULTS: Among 533 ICHs, the volume cutoff for good outcome according to ICH location was 40.5 mL for lobar, 32.5 mL for putamen/external capsule, 5.5 mL for internal capsule/globus pallidus, 6.5 mL for thalamus, 17 mL for cerebellum, and 3 mL for brainstem. ICH smaller than the cutoff for all supratentorial sites had higher odds of good outcomes (all P<0.05). Volumes exceeding 48 mL for lobar, 41 mL for putamen/external capsule, 6 mL for internal capsule/globus pallidus, 9.5 mL for thalamus, 22 mL for cerebellum, and 7.5 mL for brainstem were at greater risk of poor outcomes (all P<0.05). Mortality risks were significantly higher for volumes that exceeded 89.5 mL for lobar, 42 mL for putamen/external capsule, and 21 mL for internal capsule/globus pallidus (all P<0.001). All receiver operating characteristic models for location-specific cutoffs had good discriminant values (area under the curve >0.8), except in predicting good outcome for cerebellum. CONCLUSIONS: ICH outcomes differed with location-specific hematoma size. Location-specific volume cutoff should be considered in patient selection for ICH trials.


Assuntos
Hemorragia Cerebral , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/cirurgia , Globo Pálido , Hematoma/diagnóstico por imagem , Hematoma/cirurgia
8.
JCI Insight ; 8(4)2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36649074

RESUMO

Neuromyelitis optica spectrum disorders (NMOSD) are inflammatory autoimmune disorders of the CNS. IgG autoantibodies targeting the aquaporin-4 water channel (AQP4-IgGs) are the pathogenic effector of NMOSD. Dysregulated T follicular helper (Tfh) cells have been implicated in loss of B cell tolerance in autoimmune diseases. The contribution of Tfh cells to disease activity and therapeutic potential of targeting these cells in NMOSD remain unclear. Here, we established an autoimmune model of NMOSD by immunizing mice against AQP4 via in vivo electroporation. After AQP4 immunization, mice displayed AQP4 autoantibodies in blood circulation, blood-brain barrier disruption, and IgG infiltration in spinal cord parenchyma. Moreover, AQP4 immunization induced motor impairments and NMOSD-like pathologies, including astrocytopathy, demyelination, axonal loss, and microglia activation. These were associated with increased splenic Tfh, Th1, and Th17 cells; memory B cells; and plasma cells. Aqp4-deficient mice did not display motor impairments and NMOSD-like pathologies after AQP4 immunization. Importantly, abrogating ICOS/ICOS-L signaling using anti-ICOS-L antibody depleted Tfh cells and suppressed the response of Th1 and Th17 cells, memory B cells, and plasma cells in AQP4-immunized mice. These findings were associated with ameliorated motor impairments and spinal cord pathologies. This study suggests a role of Tfh cells in the pathophysiology of NMOSD in a mouse model with AQP4 autoimmunity and provides an animal model for investigating the immunological mechanisms underlying AQP4 autoimmunity and developing therapeutic interventions targeting autoimmune reactions in NMOSD.


Assuntos
Neuromielite Óptica , Animais , Camundongos , Neuromielite Óptica/complicações , Neuromielite Óptica/patologia , Células T Auxiliares Foliculares/metabolismo , Aquaporina 4 , Autoanticorpos , Imunoglobulina G
9.
Biomed Pharmacother ; 158: 114141, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36542987

RESUMO

Diabetic neuropathy (DN) is a long-term complication of diabetes mellitus, affecting different periphery nerve systems including sensory and motor neurons. Hyperglycemia is the major cause of DN with symptoms such as weakness of balance or coordination, insensitivity to sensation, weakness of the muscles as well as numbness and pain in limbs Analgesic drug such as opioids can be effective to relief neuropathy pain but there is no effective treatment. Adiponectin is an anti-diabetic adipokine, which possesses insulin-sensitizing and neuroprotective effects. In this project, we aim to identify an agent which is dual acting to opioid and adiponectin receptors. Within a virtual screening repositioning campaign, a large collection of compounds with different structures comprehensive of adipoRon-like piperidine derivatives was screened by docking. Recently developed opioid receptor benzomorphanic agonists finally emerged as good ligands to adiponectin receptors showing some 2D and 3D structural similarities with AdipoRon. Particularly, we have identified (+)-MML1017, which has high affinity to the same binding domain of AdipoR1 and AdipoR2 as AdipoRon. Our western blot results indicate (+)-MML1017 activates AMPK phosphorylation through both adipoR1 and adipoR2 in neuronal cell line. Moreover, pretreatment of (+)-MML1017 can improve the cell viability with motor neurons under hyperglycermic conditions. The (+)-MML1017 also activates µ-opioid receptor cells in a concentration-dependent manner. Our study identified a novel compound having dual activity on opioid receptors and adiponectin receptors that may have analgesic effects and neuroprotective effects to treat diabetic neuropathy.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Fármacos Neuroprotetores , Humanos , Receptores de Adiponectina/metabolismo , Analgésicos Opioides , Neuropatias Diabéticas/tratamento farmacológico , Receptores Opioides , Adiponectina/metabolismo
10.
Stroke ; 54(1): 78-86, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36321455

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) survivors are at high risk for recurrent stroke and cardiovascular events. Blood pressure (BP) control represents the most potent intervention to lower these risks, but optimal treatment targets in this patient population remain unknown. We sought to determine whether survivors of ICH achieving more intensive BP control than current guideline recommendations (systolic BP <130 mmHg and diastolic BP <80 mmHg) were at lower risk of major adverse cardiovascular and cerebrovascular events and mortality. METHODS: We analyzed data for 1828 survivors of spontaneous ICH from 2 cohort studies. Follow-up BP measurements were recorded 3 and 6 months after ICH, and every 6 months thereafter. Outcomes of interest were major adverse cardiovascular and cerebrovascular events (recurrent ICH, incident ischemic stroke, myocardial infarction), vascular mortality (defined as mortality attributed to recurrent ICH, ischemic stroke, or myocardial infarction), and all-cause mortality. RESULTS: During a median follow-up of 46.2 months, we observed 166 recurrent ICH, 68 ischemic strokes, 69 myocardial infarction, and 429 deaths. Compared with survivors of ICH with systolic BP 120 to 129 mmHg, participants who achieved systolic BP <120 mmHg displayed reduced risk of recurrent ICH (adjusted hazard ratio [AHR], 0.74 [95% CI, 0.59-0.94]) and major adverse cardiovascular and cerebrovascular events (AHR, 0.69 [95% CI, 0.53-0.92]). All-cause mortality (AHR, 0.76 [95% CI, 0.57-1.03]) and vascular mortality (AHR, 0.68 [95% CI, 0.45-1.01]) did not differ significantly. Among participants aged >75 years or with modified Rankin Scale score 4 to 5, systolic BP <120 mmHg was associated with increased all-cause mortality (AHR, 1.38 [95% CI, 1.02-1.85] and AHR, 1.36 [95% CI, 1.03-1.78], respectively), but not vascular mortality. We found no differences in outcome rates between survivors of ICH with diastolic BP <70 versus 70 to 79 mmHg. CONCLUSIONS: Targeting systolic BP <120 mmHg in select groups of survivors of ICH could result in decreased major adverse cardiovascular and cerebrovascular events risk without increasing mortality. Our findings warrant investigation in dedicated randomized controlled trials.


Assuntos
AVC Isquêmico , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Pressão Sanguínea/fisiologia , Hemorragia Cerebral/epidemiologia , Infarto do Miocárdio/complicações , Estudos de Coortes , AVC Isquêmico/complicações , Acidente Vascular Cerebral/complicações
11.
Front Aging Neurosci ; 14: 956222, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966783

RESUMO

Background: Patients with type 2 diabetes mellitus (T2DM) and subjective cognitive decline (SCD) have a higher risk to develop Alzheimer's Disease (AD). Resting-state-functional magnetic resonance imaging (rs-fMRI) was used to document neurological involvement in the two groups from the aspect of brain dysfunction. Accumulation of amyloid-ß (Aß) starts decades ago before the onset of clinical symptoms and may already have been associated with brain function in high-risk populations. However, this study aims to compare the patterns of fractional amplitude of low-frequency fluctuations (fALFF) maps between cognitively normal high-risk groups (SCD and T2DM) and healthy elderly and evaluate the association between regional amyloid deposition and local fALFF signals in certain cortical regions. Materials and methods: A total of 18 T2DM, 11 SCD, and 18 healthy elderlies were included in this study. The differences in the fALFF maps were compared between HC and high-risk groups. Regional amyloid deposition and local fALFF signals were obtained and further correlated in two high-risk groups. Results: Compared to HC, the altered fALFF signals of regions were shown in SCD such as the left posterior cerebellum, left putamen, and cingulate gyrus. The T2DM group illustrated altered neural activity in the superior temporal gyrus, supplementary motor area, and precentral gyrus. The correlation between fALFF signals and amyloid deposition was negative in the left anterior cingulate cortex for both groups. In the T2DM group, a positive correlation was shown in the right occipital lobe and left mesial temporal lobe. Conclusion: The altered fALFF signals were demonstrated in high-risk groups compared to HC. Very early amyloid deposition in SCD and T2DM groups was observed to affect the neural activity mainly involved in the default mode network (DMN).

12.
BMJ Open ; 12(7): e053466, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840293

RESUMO

INTRODUCTION: Current international guidelines recommend ECG monitoring after an ischaemic stroke to detect atrial fibrillation (AF) in order to prevent stroke recurrence. However, optimal strategies to detect AF and the downstream management to prevent stroke recurrence remain to be established. The objective of the study was to explore the use of long-term home-based ECG monitoring for AF detection and stroke prevention in patients with a history of stroke. METHODS AND ANALYSIS: This prospective, randomised, open-label trial with blinded endpoint adjudication aimed to evaluate the efficacy of long-term home-based ECG monitoring for AF detection and stroke prevention in a 24-month period. Patients aged >18 years with a history of ischaemic stroke will be stratified according to the time from the index ischaemic stroke: <1, 1-3 and >3 years and then randomised in 1:1 to (1) home-based AF screening and (2) control. The home-based AF screening system comprises (1) a handheld single-lead ECG recorder (Comfit Healthcare Devices, Hong Kong SAR, China) and (2) a patient-facing smartphone application specially designed for the study. Patients randomised to the home-based AF group will record a 30 s single-lead ECG using a specially designed handheld ECG device every morning or when symptomatic. All remotely obtained data will be automatically transmitted in real-time through the study smartphone application to a secured cloud hosting and analysed using an artificial intelligence-based diagnostic system. When a diagnosis of AF is made with the system, the patients will be called back for a formal cardiology consultation within 1 week. The primary endpoint is the time to first detection of AF at 24 months of follow-up. Secondary endpoints include recurrent stroke or transient ischaemic attack, initiation of long-term anticoagulation therapy, hospitalisation for heart failure, cardiovascular death and all-cause death. ETHICS AND DISSEMINATION: The study protocol has been approved by the institutional review board of The University of Hong Kong, and Hong Kong West Cluster, Hospital Authority, Hong Kong SAR, China. Results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04523649.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Inteligência Artificial , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Isquemia Encefálica/complicações , Infarto Cerebral/complicações , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/etiologia
13.
J Am Heart Assoc ; 11(6): e024158, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35253479

RESUMO

Background Survivors of intracranial hemorrhage (ICH) are at increased risk for major adverse cardiovascular and cerebrovascular events (MACCE), in the form of recurrent stroke and myocardial Infarction. We investigated whether long-term blood pressure (BP) variability represents a risk factor for MACCE after ICH, independent of average BP. Methods and Results We analyzed data from prospective ICH cohort studies at Massachusetts General Hospital and the University of Hong Kong. We captured long-term (ie, visit-to-visit) BP variability, quantified as individual participants' variation coefficient. We explored determinants of systolic and diastolic BP variability and generated survival analyses models to explore their association with MACCE. Among 1828 survivors of ICH followed for a median of 46.2 months we identified 166 with recurrent ICH, 68 with ischemic strokes, and 69 with myocardial infarction. Black (coefficient +3.8, SE 1.3) and Asian (coefficient +2.2, SE 0.4) participants displayed higher BP variability. Long-term systolic BP variability was independently associated with recurrent ICH (subhazard ratio [SHR], 1.82; 95% CI, 1.19-2.79), ischemic stroke (SHR, 1.62; 95% CI, 1.06-2.47), and myocardial infarction (SHR, 1.54; 95% CI, 1.05-2.24). Average BP during follow-up did not modify the association between long-term systolic BP variability and MACCE. Conclusions Long-term BP variability is a potent risk factor for recurrent hemorrhage, ischemic stroke, and myocardial infarction after ICH, even among survivors with well-controlled hypertension. Our findings support the hypothesis that combined control of average BP and its variability after ICH is required to minimize incidence of MACCE.


Assuntos
Hipertensão , AVC Isquêmico , Infarto do Miocárdio , Acidente Vascular Cerebral , Pressão Sanguínea/fisiologia , Hemorragia Cerebral/etiologia , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia
14.
Cancers (Basel) ; 13(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771509

RESUMO

Tobacco smoking is the top risk factor for lung cancer development. Nicotine in cigarettes can induce addiction, and its derivatives become potent carcinogens after metabolic activation and activate oncogenic signaling in lung epithelial cells through their expressed nicotinic acetylcholine receptors (nAChRs). However, the effects of smoking on the tumor immune microenvironment are under investigation. In the current study, we investigated whether nicotine activation of nicotinic acetylcholine receptor subunit α7 (nAChRα7, CHRNA7) would induce PD-L1 expression in lung epithelial cells. The expression levels of nAChRα7 and PD-L1 in eight human bronchial epithelial cell (HBEC) lines were measured after treatment with cigarette smoke extract (CSE) or nicotine derivatives. The results showed that PD-L1 expression levels increased in HBECs after exposure to CSE or nicotine derivatives. This induction of PD-L1 expression could be diminished by treatment with CHRNA7 small-interfering RNA, and the relevant signaling was mediated via STAT3 phosphorylation and NRF2 expression. In summary, this study demonstrated that the well-known nicotine derivative-activated nAChRα7 could induce STAT3/NRF2 pathways and subsequently promote PD-L1 expression in normal lung epithelial cells. This information provides mechanistic insight into cigarette smoke-induced immune evasion in lung epithelial cells.

15.
Neuroimage Clin ; 32: 102867, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34751151

RESUMO

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system in which the immune system attacks the myelin and axons, consequently leading to demyelination and axonal injury. Magnetic resonance imaging (MRI) plays a pivotal role in the diagnosis of MS, and currently various types of MRI techniques have been used to detect the pathology of MS based on unique mechanisms. In this study, we applied the relayed nuclear Overhauser effect weighted (rNOEw) imaging to study human MS at clinical 3T. Three groups of subjects, including 20 normal control (NC) subjects, 14 neuromyelitis optica spectrum disorders (NMOSD) patients and 21 MS patients, were examined at a clinical 3T MRI scanner. Whole-brain rNOEw images of each subject were obtained by acquiring a control and a labeled image within four minutes. Significantly lower brain rNOEw contrast was detected in MS group compared to NC (P = 0.008) and NMOSD (P = 0.014) groups, while no significant difference was found between NC and NMOSD groups (P = 0.939). The lower rNOEw contrast of MS group compared to NC/NMOSD group was significant in white matter (P = 0.041/0.021), gray matter (P = 0.004/0.020) and brain parenchyma (P = 0.015/0.021). Moreover, MS lesions showed higher number and larger size but lower rNOEw contrast than NMOSD lesions (P = 0.002). Our proposed rNOEw imaging scheme has potential to serve as a new method for assisting MS diagnosis. Importantly, it may be used to identify MS from NMOSD.


Assuntos
Esclerose Múltipla , Neuromielite Óptica , Encéfalo/diagnóstico por imagem , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico por imagem , Neuromielite Óptica/diagnóstico por imagem
16.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445343

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune central nervous system (CNS) inflammatory disorder that can lead to serious disability and mortality. Females are predominantly affected, including those within the reproductive age. Most patients develop relapsing attacks of optic neuritis; longitudinally extensive transverse myelitis; and encephalitis, especially brainstem encephalitis. The majority of NMOSD patients are seropositive for IgG autoantibodies against the water channel protein aquaporin-4 (AQP4-IgG), reflecting underlying aquaporin-4 autoimmunity. Histological findings of the affected CNS tissues of patients from in-vitro and in-vivo studies support that AQP4-IgG is directly pathogenic in NMOSD. It is believed that the binding of AQP4-IgG to CNS aquaporin-4 (abundantly expressed at the endfoot processes of astrocytes) triggers astrocytopathy and neuroinflammation, resulting in acute attacks. These attacks of neuroinflammation can lead to pathologies, including aquaporin-4 loss, astrocytic activation, injury and loss, glutamate excitotoxicity, microglial activation, neuroinflammation, demyelination, and neuronal injury, via both complement-dependent and complement-independent pathophysiological mechanisms. With the increased understanding of these mechanisms underlying this serious autoimmune astrocytopathy, effective treatments for both active attacks and long-term immunosuppression to prevent relapses in NMOSD are increasingly available based on the evidence from retrospective observational data and prospective clinical trials. Knowledge on the indications and potential side effects of these medications are essential for a clear evaluation of the potential benefits and risks to NMOSD patients in a personalized manner. Special issues such as pregnancy and the coexistence of other autoimmune diseases require additional concern and meticulous care. Future directions include the identification of clinically useful biomarkers for the prediction of relapse and monitoring of the therapeutic response, as well as the development of effective medications with minimal side effects, especially opportunistic infections complicated by long-term immunosuppression.


Assuntos
Neuromielite Óptica/terapia , Aquaporina 4/imunologia , Autoanticorpos/fisiologia , Biomarcadores/análise , Biomarcadores/sangue , Humanos , Terapia de Imunossupressão/métodos , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/etiologia , Neuromielite Óptica/patologia
17.
J Am Heart Assoc ; 10(11): e020392, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33998241

RESUMO

Background Survivors of intracerebral hemorrhage (ICH) are at high risk for recurrent stroke, which is associated with blood pressure control. Because most recurrent stroke events occur within 12 to 18 months of the index ICH, rapid blood pressure control is likely to be crucial. We investigated the frequency and prognostic impact of uncontrolled short-term hypertension after ICH. Methods and Results We analyzed data from Massachusetts General Hospital (n=1305) and the University of Hong Kong (n=523). We classified hypertension as controlled, undertreated, or treatment resistant at 3 months after ICH and determined the following: (1) the risk factors for uncontrolled hypertension and (2) whether hypertension control at 3 months is associated with stroke recurrence and mortality. We followed 1828 survivors of ICH for a median of 46.2 months. Only 9 of 234 (4%) recurrent strokes occurred before 3 months after ICH. At 3 months, 713 participants (39%) had controlled hypertension, 755 (41%) had undertreated hypertension, and 360 (20%) had treatment-resistant hypertension. Black, Hispanic, and Asian race/ethnicity and higher blood pressure at time of ICH increased the risk of uncontrolled hypertension at 3 months (all P<0.05). Uncontrolled hypertension at 3 months was associated with recurrent stroke and mortality during long-term follow-up (all P<0.05). Conclusions Among survivors of ICH, >60% had uncontrolled hypertension at 3 months, with undertreatment accounting for the majority of cases. The 3-month blood pressure measurements were associated with higher recurrent stroke risk and mortality. Black, Hispanic, and Asian survivors of ICH and those presenting with severe acute hypertensive response were at highest risk for uncontrolled hypertension.


Assuntos
Pressão Sanguínea/fisiologia , Hemorragia Cerebral/etiologia , Hipertensão/complicações , Idoso , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/fisiopatologia , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Hipertensão/fisiopatologia , Incidência , Masculino , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo
18.
Mol Psychiatry ; 26(10): 5669-5689, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32132650

RESUMO

Circulating adiponectin (APN) levels decrease with age and obesity. On the other hand, a reduction in APN levels is associated with neurodegeneration and neuroinflammation. We previously showed that aged adiponectin knockout (APN-/-) mice developed Alzheimer's like pathologies, cerebral insulin resistance, and cognitive impairments. More recently, we also demonstrated that APN deficiency increased Aß-induced microglia activation and neuroinflammatory responses in 5xFAD mice. There is compelling evidence that deregulated insulin activities or cerebral insulin resistance contributes to neuroinflammation and Alzheimer's disease (AD) pathogenesis. Here, we demonstrated that APN levels were reduced in the brain of AD patients and 5xFAD mice. We crossbred 5xFAD mice with APN-/- mice to generate APN-deficient 5xFAD (5xFAD;APN-/-). APN deficiency in 5xFAD mice accelerated amyloid loading, increased cerebral amyloid angiopathy, and reduced insulin-signaling activities. Pharmacokinetics study demonstrated adipoRon (APN receptor agonist) was a blood-brain barrier penetrant. AdipoRon improved neuronal insulin-signaling activities and insulin sensitivity in vitro and in vivo. Chronic adipoRon treatment improved spatial memory functions and significantly rescued neuronal and synaptic loss in 5xFAD and 5xFAD;APN-/- mice. AdipoRon lowered plaque and Aß levels in AD mice. AdipoRon also exerted anti-inflammatory effects by reducing microglial and astrocytes activation as well as suppressing cerebral cytokines levels. The microglial phagocytic activity toward Aß was restored after adipoRon treatment. Our results indicated that adipoRon exerts multiple beneficial effects providing important therapeutic implications. We propose chronic adipoRon administration as a potential treatment for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Administração Oral , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Animais , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Piperidinas/uso terapêutico
19.
Diabetes Metab Res Rev ; 37(6): e3401, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32870568

RESUMO

AIMS: Sexual dimorphism has been reported in the epidemiology, neurobiologic susceptibility and clinical presentation of Alzheimer's disease (AD). As poor glycaemic control is associated with increased risks of AD, we aimed to investigate whether glycaemia-related risk factors also differ between men and women, using a retrospective, sex-specific analysis of a large Chinese cohort with diabetes. MATERIALS & METHODS: A total of 85,514 Chinese individuals with type 2 diabetes (T2D; 46,783 women and 38,731 men), aged ≥60 years, were identified from electronic health records and observed for incident AD. Multivariable Cox regression analysis was used to evaluate the associations with incident AD of several glycaemia-related risk factors, including severe hypoglycaemia, mean HbA1c and indices of HbA1c variability, in men and women separately. RESULTS: Over a median follow-up of 6 years, women had a higher incidence of AD than men (2.3% vs. 1.2%, p < 0.001). Both men and women shared the same independent non-glycaemic clinical predictors, which included older age, lower body mass index and longer duration of diabetes. However, for glycaemia-related risk factors, we observed that severe hypoglycaemia and indices of HbA1c variability were independent predictors of incident AD in women but not in men, and the associations were irrespective of their baseline glycaemic control and duration of diabetes. CONCLUSIONS: Our findings highlighted that glycaemia-related risk factors for incident AD differ between men and women with T2D. Strategies to maintain glycaemic stability and avoid severe hypoglycaemia might be especially important to preserve healthy cognition in older women with diabetes.


Assuntos
Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Hipoglicemia , Idoso , Doença de Alzheimer/epidemiologia , Glicemia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hemoglobinas Glicadas/análise , Hong Kong/epidemiologia , Humanos , Hipoglicemia/epidemiologia , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
20.
J Neuroinflammation ; 17(1): 236, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782018

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) are central nervous system (CNS) autoimmune inflammatory demyelinating diseases characterized by recurrent episodes of acute optic neuritis and transverse myelitis. Aquaporin-4 immunoglobulin G (AQP4-IgG) autoantibodies, which target the water channel aquaporin-4 (AQP4) on astrocytic membrane, are pathogenic in NMOSD. Glutamate excitotoxicity, which is triggered by internalization of AQP4-glutamate transporter complex after AQP4-IgG binding to astrocytes, is involved in early NMOSD pathophysiologies. We studied the effects of memantine, a N-methyl-D-aspartate (NMDA) receptor antagonist, on motor impairments and spinal cord pathologies in mice which received human AQP4-IgG. METHODS: Purified IgG from AQP4-IgG-seropositive NMOSD patients were passively transferred to adult C57BL/6 mice with disrupted blood-brain barrier. Memantine was administered by oral gavage. Motor impairments of the mice were assessed by beam walking test. Spinal cords of the mice were assessed by immunofluorescence and ELISA. RESULTS: Oral administration of memantine ameliorated the motor impairments induced by AQP4-IgG, no matter the treatment was initiated before (preventive) or after (therapeutic) disease flare. Memantine profoundly reduced AQP4 and astrocyte loss, and attenuated demyelination and axonal loss in the spinal cord of mice which had received AQP4-IgG. The protective effects of memantine were associated with inhibition of apoptosis and suppression of neuroinflammation, with decrease in microglia activation and neutrophil infiltration and reduction of increase in levels of proinflammatory cytokines including interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). In addition, memantine elevated growth factors including brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and vascular endothelial growth factor (VEGF) in the spinal cord. CONCLUSIONS: Our findings support that glutamate excitotoxicity and neuroinflammation play important roles in complement-independent pathophysiology during early development of NMOSD lesions, and highlight the potential of oral memantine as a therapeutic agent in NMOSD acute attacks.


Assuntos
Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Memantina/uso terapêutico , Transtornos Motores/tratamento farmacológico , Neuromielite Óptica/tratamento farmacológico , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Aquaporina 4/imunologia , Modelos Animais de Doenças , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Humanos , Imunoglobulina G/imunologia , Memantina/farmacologia , Camundongos , Transtornos Motores/imunologia , Transtornos Motores/patologia , Neuromielite Óptica/imunologia , Neuromielite Óptica/patologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/imunologia , Medula Espinal/patologia
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