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1.
J Immunol ; 211(12): 1844-1857, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909827

RESUMO

Prior studies have defined multiple, but inconsistent, roles for the enigmatic pattern recognition receptor NLRX1 in regulating several cancer-associated biological functions. In this study, we explore the role of NLRX1 in the highly metastatic murine 4T1 mammary tumor model. We describe a functional dichotomy of NLRX1 between two different cellular contexts: expression in healthy host cells versus expression in the 4T1 tumor cells. Using Nlrx1-/- mice engrafted with 4T1 tumors, we demonstrate that NLRX1 functions as a tumor suppressor when expressed in the host cells. Specifically, NLRX1 in healthy host cells attenuates tumor growth and lung metastasis through suppressing characteristics of epithelial-mesenchymal transition and the lung metastatic niche. Conversely, we demonstrate that NLRX1 functions as a tumor promoter when expressed in 4T1 tumor cells using gain- and loss-of-function studies both in vitro and in vivo. Mechanistically, NLRX1 in the tumor cells augments 4T1 aggressiveness and metastasis through regulating epithelial-mesenchymal transition hallmarks, cell death, proliferation, migration, reactive oxygen species levels, and mitochondrial respiration. Collectively, we provide critical insight into NLRX1 function and establish a dichotomous role of NLRX1 in the 4T1 murine mammary carcinoma model that is dictated by cellular context.


Assuntos
Neoplasias Mamárias Animais , Animais , Camundongos , Linhagem Celular Tumoral , Mitocôndrias/metabolismo , Transição Epitelial-Mesenquimal , Metástase Neoplásica , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
2.
Annu Rev Physiol ; 83: 127-151, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33228454

RESUMO

GDF15 is a cell activation and stress response cytokine of the glial cell line-derived neurotrophic factor family within the TGF-ß superfamily. It acts through a recently identified orphan member of the GFRα family called GFRAL and signals through the Ret coreceptor. Cell stress and disease lead to elevated GDF15 serum levels, causing anorexia, weight loss, and alterations to metabolism, largely by actions on regions of the hindbrain. These changes restore homeostasis and, in the case of obesity, cause a reduction in adiposity. In some diseases, such as advanced cancer, serum GDF15 levels can rise by as much as 10-100-fold, leading to an anorexia-cachexia syndrome, which is often fatal. This review discusses how GDF15 regulates appetite and metabolism, the role it plays in resistance to obesity, and how this impacts diseases such as diabetes, nonalcoholic fatty liver disease, and anorexia-cachexia syndrome. It also discusses potential therapeutic applications of targeting the GDF15-GFRAL pathway and lastly suggests some potential unifying hypotheses for its biological role.


Assuntos
Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator 15 de Diferenciação de Crescimento/metabolismo , Doenças Metabólicas/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos
3.
Prostate ; 84(8): 747-755, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38544345

RESUMO

BACKGROUND: Elevated circulating growth differentiation factor (GDF15/MIC-1), interleukin 4 (IL4), and IL6 levels were associated with resistance to docetaxel in an exploratory cohort of men with metastatic castration-resistant prostate cancer (mCRPC). This study aimed to establish level 2 evidence of cytokine biomarker utility in mCRPC. METHODS: IntVal: Plasma samples at baseline (BL) and Day 21 docetaxel (n = 120). ExtVal: Serum samples at BL and Day 42 of docetaxel (n = 430). IL4, IL6, and GDF15 levels were measured by ELISA. Monocytes and dendritic cells were treated with 10% plasma from men with high or low GDF15 or recombinant GDF15. RESULTS: IntVal: Higher GDF15 levels at BL and Day 21 were associated with shorter overall survival (OS) (BL; p = 0.03 and Day 21; p = 0.004). IL4 and IL6 were not associated with outcomes. ExtVal: Higher GDF15 levels at BL and Day 42 predicted shorter OS (BL; p < 0.0001 and Day 42; p < 0.0001). Plasma from men with high GDF15 caused an increase in CD86 expression on monocytes (p = 0.03), but was not replicated by recombinant GDF15. CONCLUSIONS: Elevated circulating GDF15 is associated with poor prognosis in men with mCRPC receiving docetaxel and may be a marker of changes in the innate immune system in response to docetaxel resistance. These findings provide a strong rationale to consider GDF15 as a biomarker to guide a therapeutic trial of drugs targeting the innate immune system in combination with docetaxel in mCRPC.


Assuntos
Antineoplásicos , Biomarcadores Tumorais , Docetaxel , Fator 15 de Diferenciação de Crescimento , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Fator 15 de Diferenciação de Crescimento/sangue , Docetaxel/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/mortalidade , Biomarcadores Tumorais/sangue , Idoso , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Pessoa de Meia-Idade , Interleucina-4/sangue , Interleucina-6/sangue , Resistencia a Medicamentos Antineoplásicos , Monócitos/patologia , Monócitos/efeitos dos fármacos
4.
J Neuroinflammation ; 21(1): 63, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429643

RESUMO

Next-generation humanised mouse models and single-cell RNA sequencing (scRNAseq) approaches enable in-depth studies into human immune cell biology. Here we used NSG-SGM3 mice engrafted with human umbilical cord haematopoietic stem cells to investigate how human immune cells respond to and/or are changed by traumatic spinal cord injury (SCI). We hypothesised that the use of such mice could help advance our understanding of spinal cord injury-induced immune depression syndrome (SCI-IDS), and also how human leukocytes change as they migrate from the circulation into the lesion site. Our scRNAseq experiments, supplemented by flow cytometry, demonstrate the existence of up to 11 human immune cell (sub-) types and/or states across the blood and injured spinal cord (7 days post-SCI) of humanised NSG-SGM3 mice. Further comparisons of human immune cell transcriptomes between naïve, sham-operated and SCI mice identified a total of 579 differentially expressed genes, 190 of which were 'SCI-specific' (that is, genes regulated only in response to SCI but not sham surgery). Gene ontology analysis showed a prominent downregulation of immune cell function under SCI conditions, including for T cell receptor signalling and antigen presentation, confirming the presence of SCI-IDS and the transcriptional signature of human leukocytes in association with this phenomenon. We also highlight the activating influence of the local spinal cord lesion microenvironment by comparing the transcriptomes of circulating versus infiltrated human immune cells; those isolated from the lesion site were enriched for genes relating to both immune cell activity and function (e.g., oxidative phosphorylation, T cell proliferation and antigen presentation). We lastly applied an integrated bioinformatics approach to determine where immune responses in humanised NSG-SGM3 mice appear congruent to the native responses of human SCI patients, and where they diverge. Collectively, our study provides a valuable resource and methodological framework for the use of these mice in translational research.


Assuntos
Doenças da Medula Espinal , Traumatismos da Medula Espinal , Camundongos , Humanos , Animais , Traumatismos da Medula Espinal/metabolismo , Leucócitos/patologia , Expressão Gênica , Análise de Sequência de RNA
5.
Br J Clin Pharmacol ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297237

RESUMO

The latest country-specific regulatory guidance for assessing effectiveness of risk minimization measures (RMM) strategies was identified across five continents-Africa (Egypt, South Africa), Asia (Australia, China, Japan, South Korea, Singapore), Europe (EU-27, United Kingdom), North America (Unites States, Canada) and South America (Brazil)-and compared to the Reporting recommendation Intended for pharmaceutical Risk Minimization Evaluation Studies (RIMES) checklist, developed to assess the quality of effectiveness evaluations and endorsed by the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP). RIMES checklist items address study hypothesis, participants, measures, statistical analysis and results. European Medical Agency (EMA) and Food and Drug Administration (FDA) guidance only partially aligned with RIMES, primarily for measures and results. In the absence of country-specific guidance, most countries recommended following EMA or FDA guidelines; Japan and South Africa mentioned the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH E2E) guideline; Brazil and China had no guidance/recommendations. Worldwide, there was a lack of RMM-specific guidance and, when guidance existed, they were not harmonized, and alignment with the RIMES checklist was limited.

6.
Biol Res ; 57(1): 74, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39443981

RESUMO

BACKGROUND: Lung cancer constitutes the leading cause of cancer mortality. High levels of endothelin-1 (ET-1), its cognate receptor ETAR and its activating enzyme, the endothelin-converting enzyme-1 (ECE-1), have been reported in several cancer types, including lung cancer. ECE-1 comprises four isoforms, which only differ in their cytoplasmic N-terminus. Protein kinase CK2 phosphorylates the N-terminus of isoform ECE-1c, increasing its stability and leading to enhanced invasiveness in glioblastoma and colorectal cancer cells, which is believed to be mediated by the amino acid residue Lys-6, a conserved putative ubiquitination site neighboring the CK2-phosphorylated residues Ser-18 and Ser-20. Whether Lys-6 is linked to the acquisition of a cancer stem cell (CSC)-like phenotype and aggressiveness in human non-small cell lung cancer (NSCLC) cells has not been studied. METHODS: In order to establish the role of Lys-6 in the stability of ECE-1c and its involvement in lung cancer aggressiveness, we mutated this residue to a non-ubiquitinable arginine and constitutively expressed the wild-type (ECE-1cWT) and mutant (ECE-1cK6R) proteins in A549 and H1299 human NSCLC cells by lentiviral transduction. We determined the protein stability of these clones alone or in the presence of the CK2 inhibitor silmitasertib, compared to ECE-1cWT and mock-transduced cells. In addition, the concentration of secreted ET-1 in the growth media was determined by ELISA. Expression of stemness genes were determined by Western blot and RT-qPCR. Chemoresistance to cisplatin was studied by MTS viability assay. Migration and invasion were measured through transwell and Matrigel assays, respectively, and the side-population was determined using flow cytometry. RESULTS: ECE-1cK6R displayed higher stability in NSCLC cells compared to ECE-1cWT-expressing cells, but ET-1 secreted levels showed no difference up to 48 h. Most importantly, ECE-1cK6R promoted expression of the stemness genes c-Myc, Sox-2, Oct-4, CD44 and CD133, which enhance cellular self-renewal capability. Also, the ECE-1cK6R-expressing cells showed higher cisplatin chemoresistance, correlating with an augmented side-population abundance due to the increased expression of the ABCG2 efflux pump. Finally, the ECE-1cK6R-expressing cells showed enhanced invasiveness, which correlated with the regulated expression of known EMT markers. CONCLUSIONS: Our findings suggest an important role of ECE-1c in lung cancer. ECE-1c is key in a non-canonical ET-1-independent mechanism which triggers a CSC-like phenotype, leading to enhanced lung cancer aggressiveness. Underlying this mechanism, ECE-1c is stabilized upon phosphorylation by CK2, which is upregulated in many cancers. Thus, phospho-ECE-1c may be considered as a novel prognostic biomarker of recurrence, as well as the CK2 inhibitor silmitasertib as a potential therapy for lung cancer patients.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Enzimas Conversoras de Endotelina , Neoplasias Pulmonares , Humanos , Enzimas Conversoras de Endotelina/metabolismo , Enzimas Conversoras de Endotelina/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Antineoplásicos/farmacologia , Células-Tronco Neoplásicas/metabolismo , Western Blotting
7.
J Neuroeng Rehabil ; 21(1): 134, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103946

RESUMO

There are over 5.3 million Americans who face acquired brain injury (ABI)-related disability as well as almost 800,000 who suffer from stroke each year. To improve mobility and quality of life, rehabilitation professionals often focus on walking recovery soon after hospital discharge for ABI. Reduced propulsion capacity (force output of the lower limbs to counteract ground reaction forces) negatively impacts walking ability and complicates recovery during rehabilitation for brain injured people. We describe a method, using backward-directed resistance (BDR) in a robotic-based treadmill device, to allow measurement of maximum walking propulsion force (MWPF) that is not otherwise possible during overground walking assessment. Our objective was to test the construct validity of a maximum walking propulsion force (MWPF) measure that reflects a person's propulsive strength against applied BDR, while walking on a robotic treadmill-based device for participants with acquired brain injury (ABI). Our study enrolled 14 participants with ABI at an in inpatient rehabilitation in Galveston, TX from 8/1/21 - 4/31/22. The range of weight-adjusted MWPF was 2.6-27.1% body weight (%BW), mean 16.5 ± 8.4%BW, reflecting a wide range of propulsive force capability. The strongest correlation with overground tests was between the 6-minute walk test (6-MWT) distance and the MWPF values (r = 0.83, p < 0.001) with moderate correlations between the 10-meter walk tests at comfortable (CWS) and fast speeds (FWS). The Five Times Sit-to-Stand (used as a standard clinical measure of functional lower extremity strength) and MWPF tests were poorly correlated (r = 0.26, p = 0.4). Forward model selection included 6-MWT distance, age, and overground CWS as significant partial predictors of MWPF. We conclude that this novel MWPF measure is a valid representation of maximum propulsive force effort during walking for people post-ABI. Additional research could help determine the impact of interventions designed to increase propulsive force generation during rehabilitation training to improve overground walking performance.


Assuntos
Lesões Encefálicas , Robótica , Caminhada , Humanos , Masculino , Caminhada/fisiologia , Feminino , Pessoa de Meia-Idade , Lesões Encefálicas/reabilitação , Lesões Encefálicas/fisiopatologia , Adulto , Robótica/instrumentação , Teste de Esforço/métodos , Teste de Esforço/instrumentação , Idoso , Fenômenos Biomecânicos
8.
Int J Mol Sci ; 25(14)2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39063198

RESUMO

Anti-IgLON5 (IgLON5-IgG)-associated disease is a newly defined clinical entity. This literature review aims to evaluate its pathogenesis, which remains a pivotal question. Features that favour a primary neurodegenerative mechanism include the non-inflammatory tauopathy neuropathological signature and overrepresentation of microtubule-associated protein tau (MAPT) H1/H1 genotype as seen in other sporadic tauopathies. In contrast, the cell-surface localisation of IgLON5, capability of anti-IgLON5 antibodies to exert direct in vitro pathogenicity and disrupt IgLON5 interactions with its binding partners, human leukocyte antigen (HLA)-DRB1*10:01 and HLA-DQB1*05:01 allele preponderance with high affinity binding of IgLON5 peptides, and responsiveness to immunotherapy favour a primary autoimmune process. The presentation and course of anti-IgLON5-associated disease is heterogenous; hence, we hypothesise that a multitude of immune mechanisms are likely simultaneously operational in this disease cohort.


Assuntos
Moléculas de Adesão Celular Neuronais , Imunoglobulina G , Humanos , Moléculas de Adesão Celular Neuronais/imunologia , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Tauopatias/imunologia , Tauopatias/genética , Tauopatias/metabolismo , Animais , Proteínas tau/imunologia , Proteínas tau/metabolismo , Proteínas tau/genética , Autoanticorpos/imunologia
9.
Annu Rev Pharmacol Toxicol ; 60: 9-30, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31914894

RESUMO

Here, I recount some adventures that I and my colleagues have had over some 60 years since 1957 studying the effects of drugs and neurotransmitters on neuronal excitability and ion channel function, largely, but not exclusively, using sympathetic neurons as test objects. Studies include effects of centrally active drugs on sympathetic transmission; neuronal action and neuroglial uptake of GABA in the ganglia and brain; the action of muscarinic agonists on sympathetic neurons; the action of bradykinin on neuroblastoma-derived cells; and the identification of M-current as a target for muscarinic action, including experiments to determine its distribution, molecular composition, neurotransmitter sensitivity, and intracellular regulation by phospholipids and their hydrolysis products. Techniques used include electrophysiological recording (extracellular, intracellular microelectrode, whole-cell, and single-channel patch-clamp), autoradiography, messenger RNA and complementary DNA expression, antibody injection, antisense knockdown, and membrane-targeted lipidated peptides. I finish with some recollections about my scientific career, funding, and changes in laboratory life and pharmacology research over the past 60 years.


Assuntos
Canais Iônicos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Farmacologia , Animais , Humanos , Canais Iônicos/metabolismo , Neurônios/metabolismo , Neurotransmissores/metabolismo , Preparações Farmacêuticas/administração & dosagem
10.
Cancer Cell Int ; 23(1): 318, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072958

RESUMO

BACKGROUND: Gallbladder cancer (GBC) is a prevalent and deadly biliary tract carcinoma, often diagnosed at advanced stages with limited treatment options. The 5-year survival rate varies widely from 4 to 60%, mainly due to differences in disease stage detection. With only a small fraction of patients having resectable tumors and a high incidence of metastasis, advanced GBC stages are characterized by significant chemoresistance. Identification of new therapeutic targets is crucial, and recent studies have shown that the Endothelin-1 (ET-1) signaling pathway, involving ETAR and/or ETBR receptors (ETRs), plays a crucial role in promoting tumor aggressiveness in various cancer models. Blocking one or both receptors has been reported to reduce invasiveness and chemoresistance in cancers like ovarian, prostate, and colon. Furthermore, transcriptomic studies have associated ET-1 levels with late stages of GBC; however, it remains unclear whether its signaling or its inhibition has implications for its aggressiveness. Although the role of ET-1 signaling in gallbladder physiology is minimally understood, its significance in other tumor models leads us to hypothesize its involvement in GBC malignancy. RESULTS: In this study, we investigated the expression of ET-1 pathway proteins in three GBC cell lines and a primary GBC culture. Our findings demonstrated that both ETAR and ETBR receptors are expressed in GBC cells and tumor samples. Moreover, we successfully down-regulated ET-1 signaling using a non-selective ETR antagonist, Macitentan, which resulted in reduced migratory and invasive capacities of GBC cells. Additionally, Macitentan treatment chemosensitized the cells to Gemcitabine, a commonly used therapy for GBC. CONCLUSION: For the first time, we reveal the role of the ET-1 pathway in GBC cells, providing insight into the potential therapeutic targeting of its receptors to mitigate invasion and chemoresistance in this cancer with limited treatment options. These findings pave the way for further exploration of Macitentan or other ETR antagonists as potential therapeutic strategies for GBC management. In summary, our study represents a groundbreaking contribution to the field by providing the first evidence of the ET 1 pathway's pivotal role in modulating the behavior and aggressiveness of GBC cells, shedding new light on potential therapeutic targets.

11.
Am J Obstet Gynecol ; 229(3): 214-221, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37120051

RESUMO

Management of obstetrical and gynecologic patients with hernias poses challenges to providers. Risks for hernia development include well-described factors that impair surgical wound healing and increase abdominal pressure. Among the diverse populations cared for by obstetricians and gynecologists, pregnant patients and those with gynecologic malignancies are at the highest risk for hernia formation. This article provides an overview of the existing literature, with a focus on patients cared for by obstetrician-gynecologists and commonly encountered preoperative and intraoperative scenarios. We highlight scenarios when a hernia repair is not commonly performed, including those of patients undergoing nonelective surgeries with known or suspected gynecologic cancers. Finally, we offer multidisciplinary recommendations on the timing of elective hernia repair with obstetrical and gynecologic procedures, with attention to the primary surgical procedure, the type of preexisting hernia, and patient characteristics.


Assuntos
Hérnia Ventral , Gravidez , Humanos , Feminino , Hérnia Ventral/etiologia , Hérnia Ventral/cirurgia , Obstetra , Ginecologista , Telas Cirúrgicas , Recidiva Local de Neoplasia/etiologia , Fatores de Risco , Herniorrafia/efeitos adversos , Herniorrafia/métodos
12.
Int J Mol Sci ; 24(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37834458

RESUMO

Alzheimer's disease (AD) is a growing global health crisis affecting millions and incurring substantial economic costs. However, clinical diagnosis remains challenging, with misdiagnoses and underdiagnoses being prevalent. There is an increased focus on putative, blood-based biomarkers that may be useful for the diagnosis as well as early detection of AD. In the present study, we used an unbiased combination of machine learning and functional network analyses to identify blood gene biomarker candidates in AD. Using supervised machine learning, we also determined whether these candidates were indeed unique to AD or whether they were indicative of other neurodegenerative diseases, such as Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). Our analyses showed that genes involved in spliceosome assembly, RNA binding, transcription, protein synthesis, mitoribosomes, and NADH dehydrogenase were the best-performing genes for identifying AD patients relative to cognitively healthy controls. This transcriptomic signature, however, was not unique to AD, and subsequent machine learning showed that this signature could also predict PD and ALS relative to controls without neurodegenerative disease. Combined, our results suggest that mRNA from whole blood can indeed be used to screen for patients with neurodegeneration but may be less effective in diagnosing the specific neurodegenerative disease.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Transcriptoma , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Biomarcadores/metabolismo
13.
Cardiovasc Drugs Ther ; 36(2): 217-227, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33555510

RESUMO

PURPOSE: The present study was to determine whether OP2113 could limit myocardial infarction size and the no-reflow phenomenon in a rat myocardial ischemia/reperfusion model. METHODS: Rat heart-isolated mitochondria (RHM) were used to investigate mitochondrial respiration and mitochondrial reactive oxygen species (mtROS) generation both in normal conditions and in ischemia/reperfusion-mimicking conditions (using high concentrations of succinate). Human skeletal muscle myoblasts (HSMM) in culture were used to investigate the cellular intermittent deprivation in energy substrates and oxygen as reported in ischemia/reperfusion conditions. In vivo, rats were anesthetized and subjected to 30 min of left coronary artery occlusion followed by 3 h of reperfusion. Rats were randomized to receive OP2113 as an intravenous infusion starting either 5 min prior to coronary artery occlusion (preventive), or 5 min prior to reperfusion (curative), or to receive vehicle starting 5 min prior to coronary artery occlusion. Infusions continued until the end of the study (3 h of reperfusion). RESULTS: RHM treated with OP2113 showed a concentration-dependent reduction of succinate-induced mtROS generation. In HSMM cells, OP2113 treatment (5-10 µM) during 48H prevented the reduction in the steady-state level of ATP measured just after reperfusion injuries and decreased the mitochondrial affinity to oxygen. In vivo, myocardial infarct size, expressed as the percentage of the ischemic risk zone, was significantly lower in the OP2113-treated preventive group (44.5 ± 2.9%) versus that in the vehicle group (57.0 ± 3.6%; p < 0.05), with a non-significant trend toward a smaller infarct size in the curative group (50.8 ± 3.9%). The area of no reflow as a percentage of the risk zone was significantly smaller in both the OP2113-treated preventive (28.8 ± 2.4%; p = 0.026 vs vehicle) and curative groups (30.1 ± 2.3%; p = 0.04 vs vehicle) compared with the vehicle group (38.9 ± 3.1%). OP2113 was not associated with any hemodynamic changes. CONCLUSIONS: These results suggest that OP2113 is a promising mitochondrial ROS-modulating agent to reduce no-reflow as well as to reduce myocardial infarct size, especially if it is on board early in the course of the infarction. It appears to have benefit on no-reflow even when administered relatively late in the course of ischemia.


Assuntos
Doença da Artéria Coronariana , Oclusão Coronária , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Animais , Ratos , Circulação Coronária , Modelos Animais de Doenças , Isquemia , Reperfusão Miocárdica , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Oxigênio , Succinatos
14.
PLoS Med ; 18(7): e1003656, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34228725

RESUMO

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus-cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)-confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of "high responders" maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design.


Assuntos
Anticorpos Neutralizantes/imunologia , SARS-CoV-2/patogenicidade , Adulto , Anticorpos Antivirais/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , SARS-CoV-2/imunologia
15.
Hum Mol Genet ; 28(2): 269-278, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30285234

RESUMO

Epidemiological, molecular and genetic studies have indicated that high serum vitamin D levels are associated with lower risk of several autoimmune diseases. The vitamin D receptor (VDR) binding sites in monocytes and dendritic cells (DCs) are more common in risk genes for diseases with latitude dependence than in risk genes for other diseases. The transcription factor genes Zinc finger MIZ domain-containing protein 1 (ZMIZ1) and interferon regulatory factor 8 (IRF8)-risk genes for many of these diseases-have VDR binding peaks co-incident with the risk single nucleotide polymorphisms (SNPs). We show these genes are responsive to vitamin D: ZMIZ1 expression increased and IRF8 expression decreased, and this response was affected by genotype in different cell subsets. The IL10/IL12 ratio in tolerogenic DCs increased with vitamin D. These data indicate that vitamin D regulation of ZMIZ1 and IRF8 in DCs and monocytes contribute to latitude-dependent autoimmune disease risk.


Assuntos
Doenças Autoimunes/genética , Diferenciação Celular/genética , Fatores Reguladores de Interferon/genética , Monócitos/citologia , Fatores de Transcrição/genética , Vitamina D/farmacologia , Vitaminas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Geografia Médica , Humanos
16.
Am J Physiol Cell Physiol ; 318(3): C476-C485, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31875698

RESUMO

Cell migration is centrally involved in a myriad of physiological processes, including morphogenesis, wound healing, tissue repair, and metastatic growth. The bioenergetics that underlie migratory behavior are not fully understood, in part because of variations in cell culture media and utilization of experimental cell culture systems that do not model physiological connective extracellular fibrous networks. In this study, we evaluated the bioenergetics of C2C12 myoblast migration and force production on fibronectin-coated nanofiber scaffolds of controlled diameter and alignment, fabricated using a nonelectrospinning spinneret-based tunable engineered parameters (STEP) platform. The contribution of various metabolic pathways to cellular migration was determined using inhibitors of cellular respiration, ATP synthesis, glycolysis, or glucose uptake. Despite immediate effects on oxygen consumption, mitochondrial inhibition only modestly reduced cell migration velocity, whereas inhibitors of glycolysis and cellular glucose uptake led to striking decreases in migration. The migratory metabolic sensitivity was modifiable based on the substrates present in cell culture media. Cells cultured in galactose (instead of glucose) showed substantial migratory sensitivity to mitochondrial inhibition. We used nanonet force microscopy to determine the bioenergetic factors responsible for single-cell force production and observed that neither mitochondrial nor glycolytic inhibition altered single-cell force production. These data suggest that myoblast migration is heavily reliant on glycolysis in cells grown in conventional media. These studies have wide-ranging implications for the causes, consequences, and putative therapeutic treatments aimed at cellular migration.


Assuntos
Movimento Celular/fisiologia , Metabolismo Energético/fisiologia , Nanofibras , Animais , Antracenos/farmacologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Galactose/farmacologia , Glicólise/efeitos dos fármacos , Glicólise/fisiologia , Camundongos
17.
J Inherit Metab Dis ; 43(4): 800-818, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32030781

RESUMO

Clinical guidance is often sought when prescribing drugs for patients with primary mitochondrial disease. Theoretical considerations concerning drug safety in patients with mitochondrial disease may lead to unnecessary withholding of a drug in a situation of clinical need. The aim of this study was to develop consensus on safe medication use in patients with a primary mitochondrial disease. A panel of 16 experts in mitochondrial medicine, pharmacology, and basic science from six different countries was established. A modified Delphi technique was used to allow the panellists to consider draft recommendations anonymously in two Delphi rounds with predetermined levels of agreement. This process was supported by a review of the available literature and a consensus conference that included the panellists and representatives of patient advocacy groups. A high level of consensus was reached regarding the safety of all 46 reviewed drugs, with the knowledge that the risk of adverse events is influenced both by individual patient risk factors and choice of drug or drug class. This paper details the consensus guidelines of an expert panel and provides an important update of previously established guidelines in safe medication use in patients with primary mitochondrial disease. Specific drugs, drug groups, and clinical or genetic conditions are described separately as they require special attention. It is important to emphasise that consensus-based information is useful to provide guidance, but that decisions related to drug prescribing should always be tailored to the specific needs and risks of each individual patient. We aim to present what is current knowledge and plan to update this regularly both to include new drugs and to review those currently included.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/induzido quimicamente , Preparações Farmacêuticas , Consenso , Técnica Delphi , Desenho de Fármacos , Humanos , Internacionalidade , Mitocôndrias/metabolismo , Guias de Prática Clínica como Assunto , Testes de Toxicidade
18.
J Acoust Soc Am ; 148(6): 3417, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33379891

RESUMO

The energy method is used on the radial and circumferential displacement mode shapes of tapered piezoelectric slotted cylinder projectors to determine the electro-mechanical equivalent circuit parameters for the transducer. Results are determined for acoustically unloaded conditions for any degree of shell tapering. The resonance frequency (fr), mechanical quality factor (Qm), and electro-mechanical coupling factor (keff) are calculated and compared to measured data.

19.
J Acoust Soc Am ; 148(5): 3318, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33261394

RESUMO

This paper investigates the dependence of the electromechanical properties of the tangential polarized (stripe-electroded) cylindrical piezoelements made of the hard (PZT-4 like) and soft (PZT-5A like) ceramics on the compressive circumferential stress produced by hydrostatic pressure. Results are presented for the relative change of the effective dielectric constants, elastic constants, coupling coefficients, and piezoelectric moduli. The sensitivity of dielectric constant and piezoelectric modulus to the compressive stress is shown to be less than radially polarized ceramic.

20.
J Acoust Soc Am ; 147(6): 4145, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32611158

RESUMO

Subjecting soft piezoelectric ceramics such as lead zirconate titanate (PZT)-5 to uniaxial stress in a direction perpendicular to the principal polarization axis is known to increase its transverse piezoelectric modulus [Krueger, J. Acoust. Soc. Am. 43 (3), 583-559 (1968)], however, practical transducer applications of this effect remain undeveloped. This study explores uniaxial pressure-treatment to develop experimental methods to realize practical pressure treatment, to use dynamic measurements of the electromechanical coupling coefficient k32, piezoelectric modulus, and dielectric constants, and to enhance piezoelectric properties and performance of underwater acoustic cylindrical transducer designs. The results of axial pressure treatment on parameters of the cylinders are shown to increase the coupling coefficient by about 20% and remained stable. The applicability of using pressure treated cylinders in transducer designs is investigated. The performance was analyzed under one-dimensional circumferential static compression and under the hydrostatic compression. When the improved piezoelectric cylinders are used in air-backed transducer designs, the benefit is only useful at shallow depths as it is observed that when subjected to increased hydrostatic pressure, the corresponding induced circumferential stress reduces the piezoelectric properties, namely, the coupling coefficient, to approximately its original pre-treated value. However, when the improved cylinders are used in transducers of the pressure-equalized design, such as liquid filled or free-flooded, the increase in coupling coefficient remains stable with environmental hydrostatic pressure.

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