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1.
Circ Res ; 133(1): 25-44, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37264926

RESUMO

BACKGROUND: ERK5 (extracellular signal-regulated kinase 5) is a dual kinase transcription factor containing an N-terminal kinase domain and a C-terminal transcriptional activation domain. Many ERK5 kinase inhibitors have been developed and tested to treat cancer and inflammatory diseases. However, recent data have raised questions about the role of the catalytic activity of ERK5 in proliferation and inflammation. We aimed to investigate how ERK5 reprograms myeloid cells to the proinflammatory senescent phenotype, subsequently leading to atherosclerosis. METHODS: A ERK5 S496A (dephosphorylation mimic) knock in (KI) mouse model was generated using CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9), and atherosclerosis was characterized by hypercholesterolemia induction. The plaque phenotyping in homozygous ERK5 S496A KI and wild type (WT) mice was studied using imaging mass cytometry. Bone marrow-derived macrophages were isolated from hypercholesterolemic mice and characterized using RNA sequencing and functional in vitro approaches, including senescence, mitochondria reactive oxygen species, and inflammation assays, as well as by metabolic extracellular flux analysis. RESULTS: We show that atherosclerosis was inhibited in ERK5 S496A KI mice. Furthermore, ERK5 S496 phosphorylation mediates both senescence-associated secretory phenotype and senescence-associated stemness by upregulating AHR (aryl hydrocarbon receptor) in plaque and bone marrow-derived macrophages isolated from hypercholesterolemic mice. We also discovered that ERK5 S496 phosphorylation could induce NRF2 (NFE2-related factor 2) SUMOylation at a novel K518 site to inhibit NRF2 transcriptional activity without altering ERK5 catalytic activity and mediates oxidized LDL (low-density lipoprotein)-induced senescence-associated secretory phenotype. Specific ERK5 kinase inhibitors (AX15836 and XMD8-92) also inhibited ERK5 S496 phosphorylation, suggesting the involvement of ERK5 S496 phosphorylation in the anti-inflammatory effects of these ERK5 kinase inhibitors. CONCLUSIONS: We discovered a novel mechanism by which the macrophage ERK5-NRF2 axis develops a unique senescence-associated secretory phenotype/stemness phenotype by upregulating AHR to engender atherogenesis. The finding of senescence-associated stemness phenotype provides a molecular explanation to resolve the paradox of senescence in proliferative plaque by permitting myeloid cells to escape the senescence-induced cell cycle arrest during atherosclerosis formation.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Camundongos , Aterosclerose/metabolismo , Inflamação , Proteína Quinase 7 Ativada por Mitógeno/genética , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
2.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446100

RESUMO

Fibroblast-to-myofibroblast transition (FMT) leads to excessive extracellular matrix (ECM) deposition-a well-known hallmark of fibrotic disease. Transforming growth factor-ß (TGF-ß) is the primary cytokine driving FMT, and this phenotypic conversion is associated with mitochondrial dysfunction, notably a metabolic reprogramming towards enhanced glycolysis. The objective of this study was to examine whether the establishment of favorable metabolic phenotypes in TGF-ß-stimulated fibroblasts could attenuate FMT. The hypothesis was that mitochondrial replenishment of TGF-ß-stimulated fibroblasts would counteract a shift towards glycolytic metabolism, consequently offsetting pro-fibrotic processes. Isolated mitochondria, functionalized with a dextran and triphenylphosphonium (TPP) (Dex-TPP) polymer conjugate, were administered to fibroblasts (MRC-5 cells) stimulated with TGF-ß, and effects on bioenergetics and fibrotic programming were subsequently examined. Results demonstrate that TGF-ß stimulation of fibroblasts led to FMT, which was associated with enhanced glycolysis. Dex-TPP-coated mitochondria (Dex-TPP/Mt) delivery to TGF-ß-stimulated fibroblasts abrogated a metabolic shift towards glycolysis and led to a reduction in reactive oxygen species (ROS) generation. Importantly, TGF-ß-stimulated fibroblasts treated with Dex-TPP/Mt had lessened expression of FMT markers and ECM proteins, as well as reduced migration and proliferation. Findings highlight the potential of mitochondrial transfer, as well as other strategies involving functional reinforcement of mitochondria, as viable therapeutic modalities in fibrosis.


Assuntos
Fibroblastos , Transdução de Sinais , Humanos , Fibroblastos/metabolismo , Fibrose , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fenótipo , Mitocôndrias/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Células Cultivadas
3.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35162934

RESUMO

Calcium signaling plays important roles in physiological and pathological conditions, including cutaneous melanoma, the most lethal type of skin cancer. Intracellular calcium concentration ([Ca2+]i), cell membrane calcium channels, calcium related proteins (S100 family, E-cadherin, and calpain), and Wnt/Ca2+ pathways are related to melanogenesis and melanoma tumorigenesis and progression. Calcium signaling influences the melanoma microenvironment, including immune cells, extracellular matrix (ECM), the vascular network, and chemical and physical surroundings. Other ionic channels, such as sodium and potassium channels, are engaged in calcium-mediated pathways in melanoma. Calcium signaling serves as a promising pharmacological target in melanoma treatment, and its dysregulation might serve as a marker for melanoma prediction. We documented calcium-dependent endoplasmic reticulum (ER) stress and mitochondria dysfunction, by targeting calcium channels and influencing [Ca2+]i and calcium homeostasis, and attenuated drug resistance in melanoma management.


Assuntos
Sinalização do Cálcio , Resistencia a Medicamentos Antineoplásicos , Melanoma/metabolismo , Estresse do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica , Humanos , Microambiente Tumoral , Via de Sinalização Wnt
4.
Int J Mol Sci ; 23(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36293021

RESUMO

The transformation of prostatic epithelial cells to prostate cancer (PCa) has been characterized as a transition from citrate secretion to citrate oxidation, from which one would anticipate enhanced mitochondrial complex I (CI) respiratory flux. Molecular mechanisms for this transformation are attributed to declining mitochondrial zinc concentrations. The unique metabolic properties of PCa cells have become a hot research area. Several publications have provided indirect evidence based on investigations using pre-clinical models, established cell lines, and fixed or frozen tissue bank samples. However, confirmatory respiratory analysis on fresh human tissue has been hampered by multiple difficulties. Thus, few mitochondrial respiratory assessments of freshly procured human PCa tissue have been published on this question. Our objective is to document relative mitochondrial CI and complex II (CII) convergent electron flow to the Q-junction and to identify electron transport system (ETS) alterations in fresh PCa tissue. The results document a CII succinate: quinone oxidoreductase (SQR) dominant succinate oxidative flux model in the fresh non-malignant prostate tissue, which is enhanced in malignant tissue. CI NADH: ubiquinone oxidoreductase activity is impaired rather than predominant in high-grade malignant fresh prostate tissue. Given these novel findings, succinate and CII are promising targets for treating and preventing PCa.


Assuntos
Neoplasias da Próstata , Ácido Succínico , Masculino , Humanos , Ácido Succínico/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/metabolismo , NAD/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Transporte de Elétrons , Citratos , Zinco/metabolismo
5.
Circulation ; 139(1): 119-133, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30586707

RESUMO

BACKGROUND: We have previously shown that activation of cell-autonomous innate immune signaling facilitates the transdifferentiation of fibroblasts into induced endothelial cells, and is required to generate induced endothelial cells with high fidelity for endothelial lineage. Recent studies indicate that a glycolytic switch plays a role in induced pluripotent stem cell generation from somatic cells. METHODS: Seahorse and metabolomics flux assays were used to measure the metabolic changes during transdifferentiation in vitro, and Matrigel plug assay was used to assess the effects of glycolysis modulators on transdifferentiation in vivo. RESULTS: The metabolic switch begins rapidly after activation of innate immunity, before the expression of markers of endothelial lineage. Inhibiting glycolysis impaired, whereas facilitating glycolysis enhanced, the generation of induced endothelial cells. The toll-like receptor 3 agonist poly I:C increased expression of the mitochondrial citrate transporter Slc25A1, and the nuclear ATP-citrate lyase, in association with intracellular accumulation of citrate, the precursor for acetyl coenzyme A. These metabolic changes were coordinated with increased histone acetylation during transdifferentiation. CONCLUSION: Innate immune signaling promotes a glycolytic switch that is required for transdifferentiation, both processes being attenuated by ATP-citrate lyase knockdown. These data shed light on a novel link between metabolism and epigenetic modulation in transdifferentiation.


Assuntos
Linhagem da Célula , Transdiferenciação Celular , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Glicólise , ATP Citrato (pro-S)-Liase/genética , ATP Citrato (pro-S)-Liase/metabolismo , Acetilação , Animais , Linhagem da Célula/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ácido Cítrico/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Epigênese Genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Glicólise/efeitos dos fármacos , Histonas/metabolismo , Imunidade Inata , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Mitocondriais , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Fenótipo , Poli I-C/farmacologia , Transdução de Sinais , Receptor 3 Toll-Like/agonistas , Receptor 3 Toll-Like/metabolismo
6.
Am J Transplant ; 19(5): 1568-1576, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30372580

RESUMO

Beta-cell dedifferentiation as shown by cellular colocalization of insulin with glucagon and/or vimentin, and decreased expression of MAFA and/or urocortin3 has been suggested to contribute to metabolic decompensation in type 2 diabetes, and was recently described postimplantation in islet allotransplant patients. Dysglycaemia and diabetes mellitus are often encountered preoperatively in patients undergoing pancreatectomy and islet autotransplantation (PIAT). In this series of case reports, we document variation in islet phenotypic identity in three patients with chronic pancreatitis (CP) without diabetes or significant insulin resistance who subsequently underwent PIAT. Pancreas histology was examined using colocalization of endocrine hormones, mesenchymal and pan-endocrine markers in islets, and the relative expression of MAFA and urocortin3 in insulin-expressing cells as compared to that of nondiabetic and type 2 diabetic donors. We present results of pre- and posttransplant clinical metabolic testing. Varying degrees of islet-cell dedifferentiation are identified in nondiabetic patients with CP at the time of PIAT, and may need further investigation.


Assuntos
Células Endócrinas/patologia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Pancreatite Crônica/terapia , Adulto , Biomarcadores/metabolismo , Células Endócrinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Transplante Autólogo , Adulto Jovem
7.
Angew Chem Int Ed Engl ; 58(16): 5272-5276, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30697890

RESUMO

Interaction of multiple entities and receptors, or multivalency is widely applied to achieve high affinity ligands for diagnostic and therapeutic purposes. However, lack of knowledge on receptor distribution in living subjects remains a challenge for rational structure design. Herein, we develop a force measurement platform to probe the distribution and separation of the cell surface vascular endothelial growth factor receptors (VEGFR) in live cells, and use this to assess the geometry of appropriate linkers for distinct multivalent binding modes. A tetravalent lead ZD-4, which was developed from an antitumor drug ZD6474 (Vandetanib) with combined hybrid binding effects, yielded a 2000-fold improvement in the binding affinity to VEGFR with IC50 value of 25 pm. We confirmed the improved affinity by the associated increase of tumor uptake in the VEGFR-targeting positron emission tomography (PET) imaging using U87 tumor xenograft mouse model.


Assuntos
Antineoplásicos/análise , Piperidinas/análise , Inibidores de Proteínas Quinases/análise , Quinazolinas/análise , Animais , Antineoplásicos/farmacologia , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Ligantes , Camundongos , Estrutura Molecular , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Imagem Óptica , Piperidinas/farmacologia , Tomografia por Emissão de Pósitrons , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo
8.
Adv Exp Med Biol ; 982: 113-126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28551784

RESUMO

Provision for the continuous demand for energy from the beating heart relies heavily on efficient mitochondrial activity. Non-ischemic cardiomyopathy in which oxygen supply is not limiting results from etiologies such as pressure overload. It is associated with progressive development of metabolic stress culminating in energy depletion and heart failure. The mitochondria from the ventricular walls undergoing non-ischemic cardiomyopathy are subjected to long periods of adaptation to support the changing metabolic milieu, which has been described as mal-adaptation since it ultimately results in loss of cardiac contractile function. While the chronicity of exposure to metabolic stressors, co-morbidities and thereby adaptive changes in mitochondria maybe different between ischemic and non-ischemic heart failure, the resulting pathology is very similar, especially in late stage heart failure. Understanding of the mitochondrial changes in early-stage heart failure may guide the development of mitochondrial-targeted therapeutic options to prevent progression of non-ischemic heart failure. This chapter reviews findings of mitochondrial functional changes in animal models and humans with non-ischemic heart failure. While most animal models of non-ischemic heart failure exhibit cardiac mitochondrial dysfunction, studies in humans have been inconsistent despite confirmed reduction in ATP production. This chapter also reviews the possibility of impairment of substrate supply processes upstream of the mitochondria in heart failure, and discusses potential metabolism-targeted therapeutic options.


Assuntos
Metabolismo Energético , Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Animais , Cardiotônicos/uso terapêutico , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/patologia , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fatores de Risco
9.
Am J Physiol Heart Circ Physiol ; 310(6): H667-80, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26747502

RESUMO

Mitochondrial dysfunction has been implicated as a cause of energy deprivation in heart failure (HF). Herein, we tested individual and combined effects of two pathogenic factors of nonischemic HF, inhibition of nitric oxide synthesis [with l-N(G)-nitroarginine methyl ester (l-NAME)] and hypertension [with angiotensin II (AngII)], on myocardial mitochondrial function, oxidative stress, and metabolic gene expression. l-NAME and AngII were administered individually and in combination to mice for 5 wk. Although all treatments increased blood pressure and reduced cardiac contractile function, the l-NAME + AngII group was associated with the most severe HF, as characterized by edema, hypertrophy, oxidative stress, increased expression of Nppa and Nppb, and decreased expression of Atp2a2 and Camk2b. l-NAME + AngII-treated mice exhibited robust deterioration of cardiac mitochondrial function, as observed by reduced respiratory control ratios in subsarcolemmal mitochondria and reduced state 3 levels in interfibrillar mitochondria for complex I but not for complex II substrates. Cardiac myofibrils showed reduced ADP-supported and oligomycin-inhibited oxygen consumption. Mitochondrial functional impairment was accompanied by reduced mitochondrial DNA content and activities of pyruvate dehydrogenase and complex I but increased H2O2 production and tissue protein carbonyls in hearts from AngII and l-NAME + AngII groups. Microarray analyses revealed the majority of the gene changes attributed to the l-NAME + AngII group. Pathway analyses indicated significant changes in metabolic pathways, such as oxidative phosphorylation, mitochondrial function, cardiac hypertrophy, and fatty acid metabolism in l-NAME + AngII hearts. We conclude that l-NAME + AngII is associated with impaired mitochondrial respiratory function and increased oxidative stress compared with either l-NAME or AngII alone, resulting in nonischemic HF.


Assuntos
Angiotensina II/farmacologia , Inibidores Enzimáticos/farmacologia , Insuficiência Cardíaca/etiologia , Mitocôndrias Cardíacas/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Vasoconstritores/farmacologia , Animais , Fator Natriurético Atrial , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cardiomegalia , DNA Mitocondrial/efeitos dos fármacos , DNA Mitocondrial/metabolismo , Complexo I de Transporte de Elétrons/efeitos dos fármacos , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/efeitos dos fármacos , Complexo II de Transporte de Elétrons/metabolismo , Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Camundongos , Mitocôndrias Cardíacas/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Peptídeo Natriurético Encefálico/efeitos dos fármacos , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Tipo C/efeitos dos fármacos , Peptídeo Natriurético Tipo C/genética , Precursores de Proteínas/efeitos dos fármacos , Precursores de Proteínas/genética , Complexo Piruvato Desidrogenase/efeitos dos fármacos , Complexo Piruvato Desidrogenase/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/efeitos dos fármacos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética
10.
J Card Fail ; 22(1): 73-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26370778

RESUMO

OBJECTIVES: Right ventricular failure is the primary reason for mortality in pulmonary hypertension (PH), but little is understood about the energetics of the failing right myocardium. Our aim was to examine mitochondrial function and proteomic signatures in paired remodeled right (RM-RV) and non-remodeled left (NRM-LV) ventricular tissue samples procured during heart-lung transplantation. METHODS AND RESULTS: Contractile dysfunction in RM-RV and preserved contractile function in NRM-LV were determined clinically and by echocardiography. Mitochondria were isolated from fresh paired RV and LV wall specimens of explanted hearts. Respiratory states in response to 4 substrates and an uncoupler were analyzed. Proteomic analysis on the mitochondrial isolates was performed with the use of liquid chromatography-mass spectrometry. The RM-RV mitochondria exhibited higher succinate state 4 levels with lower respiratory control ratio (RCR) compared with state 4 levels for pyruvate-malate (PM) and glutamate-malate (GM). RM-RV mitochondria also exhibited lower state 3 for palmitoyl-carnitine (PC) and state 4 for all complex I substrates compared with NRM-LV. The mean RCR were greater in RM-RVs than in NRM-LVs for PM and GM, which is consistent with tight coupling (low state 4 rates, higher RCRs); however, low RM-RV state 3 rates suggest concurrent substrate-dependent impairment in respiratory capacity. Mitochondrial proteomics revealed greater levels of mitochondrial ADP-ATP translocase and proteins of ATP synthesis, mitochondrial pyruvate and short branched chain acyl-CoA metabolism in RM-RV. CONCLUSIONS: The mitochondrial respiration and proteomics in RM-RV are different from NRM-LV. These results have important implications in expanding our understanding of RV metabolism and future management of RV failure.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Hipertensão Pulmonar/complicações , Mitocôndrias Cardíacas/metabolismo , Disfunção Ventricular Direita/fisiopatologia , Remodelação Ventricular , Adolescente , Idoso , Ecocardiografia , Complexo I de Transporte de Elétrons/metabolismo , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Pessoa de Meia-Idade , Mitocôndrias Cardíacas/enzimologia , Translocases Mitocondriais de ADP e ATP/metabolismo , Proteômica , Disfunção Ventricular Direita/etiologia
11.
Biochem Biophys Res Commun ; 459(3): 430-6, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25735978

RESUMO

A salient feature of the failing heart is metabolic remodeling towards predominant glucose metabolism and activation of the fetal gene program. Sunitinib is a multitargeted receptor tyrosine kinase inhibitor used for the treatment of highly vascularized tumors. In diabetic patients, sunitinib significantly decreases blood glucose. However, a considerable proportion of sunitinib-treated patients develop cardiac dysfunction or failure. We asked whether sunitinib treatment results in shift towards glycolysis in the heart. Glucose uptake by the heart was increased fivefold in mice treated with sunitinib. Transcript analysis by qPCR revealed an induction of genes associated with glycolysis and reactivation of the fetal gene program. Additionally, we observed a shift in the enzyme pyruvate kinase from the adult M1 (PKM1) isoform to the fetal M2 (PKM2) isoform, a hallmark of the Warburg Effect. This novel observation led us to examine whether a similar shift occurs in human heart failure. Examination of tissue from patients with heart failure similarly displayed an induction of PKM2. Moreover, this phenomenon was partially reversed following mechanical unloading. We propose that pyruvate kinase isoform switching represents a novel feature of the fetal gene program in the failing heart.


Assuntos
Proteínas de Transporte/metabolismo , Insuficiência Cardíaca/metabolismo , Proteínas de Membrana/metabolismo , Piruvato Quinase/metabolismo , Hormônios Tireóideos/metabolismo , Inibidores da Angiogênese/efeitos adversos , Animais , Proteínas de Transporte/genética , Coração Fetal/metabolismo , Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Glicólise/genética , Coração/efeitos dos fármacos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Indóis/efeitos adversos , Resistência à Insulina , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Pirróis/efeitos adversos , Piruvato Quinase/genética , Sunitinibe , Hormônios Tireóideos/genética , Proteínas de Ligação a Hormônio da Tireoide
12.
J Mol Cell Cardiol ; 68: 98-105, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24412531

RESUMO

In heart failure mitochondrial dysfunction is thought to be responsible for energy depletion and contractile dysfunction. The difficulties in procuring fresh left ventricular (LV) myocardium from humans for assessment of mitochondrial function have resulted in the reliance on surrogate markers of mitochondrial function and limited our understanding of cardiac energetics. We isolated mitochondria from fresh LV wall tissue of patients with heart failure and reduced systolic function undergoing heart transplant or left ventricular assist device placement, and compared their function to mitochondria isolated from the non-failing LV (NFLV) wall tissue with normal systolic function from patients with pulmonary hypertension undergoing heart-lung transplant. We performed detailed mitochondrial functional analyses using 4 substrates: glutamate-malate (GM), pyruvate-malate (PM) palmitoyl carnitine-malate (PC) and succinate. NFLV mitochondria showed preserved respiratory control ratios and electron chain integrity with only few differences for the 4 substrates. In contrast, HF mitochondria had greater respiration with GM, PM and PC substrates and higher electron chain capacity for PM than for PC. Surprisingly, HF mitochondria had greater respiratory control ratios and lower ADP-independent state 4 rates than NFLV mitochondria for GM, PM and PC substrates demonstrating that HF mitochondria are capable of coupled respiration ex vivo. Gene expression studies revealed decreased expression of key genes in pathways for oxidation of both fatty acids and glucose. Our results suggest that mitochondria from the failing LV myocardium are capable of tightly coupled respiration when isolated and supplied with ample substrates. Thus energy starvation in the failing heart may be the result of dysregulation of metabolic pathways, impaired substrate supply or reduced mitochondrial number but not the result of reduced mitochondrial electron transport capacity.


Assuntos
Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Adulto , Antígenos CD36/genética , Antígenos CD36/metabolismo , Estudos de Casos e Controles , Respiração Celular , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Feminino , Insuficiência Cardíaca/patologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Oxigênio/metabolismo , Transcriptoma , Adulto Jovem
13.
Nat Commun ; 15(1): 2156, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461154

RESUMO

This study establishes the physiological role of Fused in Sarcoma (FUS) in mitochondrial DNA (mtDNA) repair and highlights its implications to the pathogenesis of FUS-associated neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). Endogenous FUS interacts with and recruits mtDNA Ligase IIIα (mtLig3) to DNA damage sites within mitochondria, a relationship essential for maintaining mtDNA repair and integrity in healthy cells. Using ALS patient-derived FUS mutant cell lines, a transgenic mouse model, and human autopsy samples, we discovered that compromised FUS functionality hinders mtLig3's repair role, resulting in increased mtDNA damage and mutations. These alterations cause various manifestations of mitochondrial dysfunction, particularly under stress conditions relevant to disease pathology. Importantly, rectifying FUS mutations in patient-derived induced pluripotent cells (iPSCs) preserves mtDNA integrity. Similarly, targeted introduction of human DNA Ligase 1 restores repair mechanisms and mitochondrial activity in FUS mutant cells, suggesting a potential therapeutic approach. Our findings unveil FUS's critical role in mitochondrial health and mtDNA repair, offering valuable insights into the mechanisms underlying mitochondrial dysfunction in FUS-associated motor neuron disease.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Mitocondriais , Doença dos Neurônios Motores , Proteína FUS de Ligação a RNA , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/metabolismo , DNA Mitocondrial/genética , Ligases/metabolismo , Camundongos Transgênicos , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/metabolismo , Mutação , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , DNA Ligase Dependente de ATP/genética , DNA Ligase Dependente de ATP/metabolismo
15.
Bone ; 166: 116598, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36341949

RESUMO

Cutaneous skeletal hypophosphatemia syndrome (CSHS) is an ultra-rare mosaic disorder manifesting as skeletal dysplasia and FGF23-mediated hypophosphatemia, with some experiencing extra-osseous/extra-cutaneous manifestations, including both benign and malignant neoplasms. Like other disorders of FGF23-mediated hypophosphatemia including X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO), patients with CSHS have low serum phosphorus and active 1,25-dihydroxyvitamin D levels. Current treatment options for patients with CSHS include multiple daily doses of oral phosphorus and one or more daily doses of active vitamin D analog to correct the deficits. Recently, the fully human monoclonal antibody against FGF23 burosumab received US approval for the treatment of XLH and TIO, two rare diseases characterized by FGF23-mediated hypophosphatemia leading to rickets and osteomalacia. Given the similarities between the pathobiologies of these disorders and CSHS, we investigated the impact of burosumab on two patients, one pediatric and one adult, with CSHS who participated in separate, but similarly designed trials. In both the pediatric and adult patients, burosumab therapy was well-tolerated and contributed to clinically meaningful improvements in disease outcomes including normalization of phosphorus metabolism and markers of bone health, and improvements in skeletal abnormalities, fractures, and physical function. Reported adverse events were minimal, with only mild injection site reactions attributed to burosumab therapy. Together, these findings suggest that burosumab therapy is a promising therapeutic option for patients with CSHS.


Assuntos
Anticorpos Monoclonais Humanizados , Hipofosfatemia , Adulto , Criança , Humanos , Raquitismo Hipofosfatêmico Familiar/complicações , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Raquitismo Hipofosfatêmico Familiar/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Hipofosfatemia/tratamento farmacológico , Osteomalacia/tratamento farmacológico , Fósforo , Anticorpos Monoclonais Humanizados/uso terapêutico
16.
Res Sq ; 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37502965

RESUMO

This study establishes the physiological role of Fused in Sarcoma (FUS) in mitochondrial DNA (mtDNA) repair and highlights its implications to the pathogenesis of FUS-associated neurodegenerative diseases such as Amyotrophic lateral sclerosis (ALS). Endogenous FUS interacts with and recruits mtDNA Ligase IIIα (mtLig3) to DNA damage sites within mitochondria, a relationship essential for maintaining mtDNA repair and integrity in healthy cells. Using ALS patient-derived FUS mutant cell lines, a transgenic mouse model, and human autopsy samples, we discovered that compromised FUS functionality hinders mtLig3's repair role, resulting in increased mtDNA damage and mutations. These alterations cause various manifestations of mitochondrial dysfunction, particularly under stress conditions relevant to disease pathology. Importantly, rectifying FUS mutations in patient-derived induced pluripotent cells (iPSCs) preserves mtDNA integrity. Similarly, targeted introduction of human DNA Ligase 1 restores repair mechanisms and mitochondrial activity in FUS mutant cells, suggesting a potential therapeutic approach. Our findings unveil FUS's critical role in mitochondrial health and mtDNA repair, offering valuable insights into the mechanisms underlying mitochondrial dysfunction in FUS-associated neurodegeneration.

17.
Front Cardiovasc Med ; 10: 1212174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781317

RESUMO

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality, especially among the aging population. The "response-to-injury" model proposed by Dr. Russell Ross in 1999 emphasizes inflammation as a critical factor in atherosclerosis development, with atherosclerotic plaques forming due to endothelial cell (EC) injury, followed by myeloid cell adhesion and invasion into the blood vessel walls. Recent evidence indicates that cancer and its treatments can lead to long-term complications, including CVD. Cellular senescence, a hallmark of aging, is implicated in CVD pathogenesis, particularly in cancer survivors. However, the precise mechanisms linking premature senescence to CVD in cancer survivors remain poorly understood. This article aims to provide mechanistic insights into this association and propose future directions to better comprehend this complex interplay.

18.
Transplant Direct ; 8(10): e1367, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36204182

RESUMO

Islet and ß-cell function is intrinsic to glucose homeostasis. Pancreatectomy and islet autotransplantation (PIAT) for chronic pancreatitis (CP) treatment is a useful model for assessing islet function in the absence of immune-suppression and to perform extensive presurgical metabolic evaluations not possible from deceased donors. We recently showed that in CP-PIAT patients, preoperative islet identity loss presented with postoperative glycemic loss. Here, we examine presurgical islet function using Homeostatic Model Assessment-Beta Cell Function (%) (HOMA-ß) and glycemic variables and compared them with postsurgical insulin independence and their predicted alignment with Secretory Unit of Islet Transplant Objects (SUITO) and beta cell score after transplantation (BETA-2) scores. Methods: Seven CP-PIAT patients were assessed for ß-cell function metrics, including pretransplant and 6-mo posttransplant HOMA-ß using insulin and C-peptide and evaluations of proposed insulin independence by SUITO and BETA-2 graft function equations. These were compared with oral glucose tolerance tests and pancreas histological samples taken at the time of transplant, examined for ß-cell maturity markers. Results: Pre-PIAT, HOMA-ß (60%-100%) associated with post-PIAT insulin independence. This association was only moderately supported by post-PIAT SUITO threshold scores (≥26) but robustly by BETA-2 scores (≥16.2). Appropriate posttransplant oral glucose tolerance test curves were found in those patients with normal pretransplant HOMA-ß values. Preoperative low serological ß-cell function was displayed by concurrent evidence of ß-cell identity alterations including colocalization of insulin and glucagon, loss of urocortin-3, and increased intra-islet vimentin in patients who were insulin-dependent post-PIAT. Conclusions: These data encourage HOMA-ß assessment before PIAT for estimating posttransplant insulin independence.

19.
Cells ; 11(22)2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36429071

RESUMO

Accumulating evidence indicates that the APOA1 binding protein (AIBP)-a secreted protein-plays a profound role in lipid metabolism. Interestingly, AIBP also functions as an NAD(P)H-hydrate epimerase to catalyze the interconversion of NAD(P)H hydrate [NAD(P)HX] epimers and is renamed as NAXE. Thus, we call it NAXE hereafter. We investigated its role in NAD(P)H-involved metabolism in murine cardiomyocytes, focusing on the metabolism of hexose, lipids, and amino acids as well as mitochondrial redox function. Unbiased metabolite profiling of cardiac tissue shows that NAXE knockout markedly upregulates the ketone body 3-hydroxybutyric acid (3-HB) and increases or trends increasing lipid-associated metabolites cholesterol, α-linolenic acid and deoxycholic acid. Paralleling greater ketone levels, ChemRICH analysis of the NAXE-regulated metabolites shows reduced abundance of hexose despite similar glucose levels in control and NAXE-deficient blood. NAXE knockout reduces cardiac lactic acid but has no effect on the content of other NAD(P)H-regulated metabolites, including those associated with glucose metabolism, the pentose phosphate pathway, or Krebs cycle flux. Although NAXE is present in mitochondria, it has no apparent effect on mitochondrial oxidative phosphorylation. Instead, we detected more metabolites that can potentially improve cardiac function (3-HB, adenosine, and α-linolenic acid) in the Naxe-/- heart; these mice also perform better in aerobic exercise. Our data reveal a new role of NAXE in cardiac ketone and lipid metabolism.


Assuntos
Cetonas , NAD , Animais , Camundongos , Ácido alfa-Linolênico , NAD/metabolismo , Racemases e Epimerases , Respiração Celular
20.
J Nucl Med ; 63(11): 1708-1714, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35210298

RESUMO

Despite the advance of immunotherapy, only a small subset of patients gains long-term survival benefit. This fact represents a compelling rationale to develop immuno-PET imaging that can predict tumor response to immunotherapy. An increasing number of studies have shown that tumor-specific major histocompatibility complex II (tsMHC-II) is associated with improved responses to targeted immunotherapy. The aim of this study was to investigate the potential of tsMHC-II protein expression and its dynamic change on treatment with interferon γ (IFNγ) as a new target for immuno-PET to predict response to immunotherapy. Methods: Major histocompatibility complex II (MHC-II) antibody was radiolabeled with DOTA-chelated 64Cu to derive an MHC-II immuno-PET tracer. Two melanoma models (B16SIY, B16F10) that are respondent and nonrespondent, respectively, to PD1/PD-L1 checkpoint inhibitor were used. Both tumor models were treated with anti-PD1 and IFNγ, enabling observation of dynamic changes in tsMHC-II. Small-animal PET imaging, biodistribution, and histologic studies were performed to validate the correlation of tsMHC-II with the tumor response to the immunotherapy. Results: Fluorescence-activated cell sorting analysis of the 2 tumors supported the consensual recognition of tsMHC-II correlated with the tumor response to the immunotherapy. The in vivo PET imaging revealed higher basal levels of tsMHC-II in the responder, B16SIY, than in the nonresponder, B16F10. When treated with anti-PD1 antibody in animals, B16SIY tumors displayed a sensitive increase in tsMHC-II compared with B16F10 tumors. In IFNγ stimulation groups, the greater magnitude of tsMHC-II was further amplified when the IFNγ signaling was activated in the B16SIY tumors, as IFNγ signaling positively upregulates tsMHC-II in the tumor immunity. Subsequent histopathologic analysis supported the correlative characteristics of tsMHC-II with tumor immunity and response to cancer immunotherapy. Conclusion: Collectively, the predictive value of tsMHC-II immuno-PET was validated for stratifying tumor immunotherapy responders versus nonresponders. Monitoring sensitivity of tsMHC-II to IFNγ stimulation may provide an effective strategy to predict the tumor response to immunotherapy.


Assuntos
Melanoma , Mieloma Múltiplo , Animais , Receptor de Morte Celular Programada 1 , Distribuição Tecidual , Imunoterapia/métodos , Tomografia por Emissão de Pósitrons/métodos , Fatores Imunológicos
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