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1.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38854025

RESUMO

Pulmonary arterial hypertension (PAH) is characterized by obliterative vascular remodeling of the small pulmonary arteries (PA) and progressive increase in pulmonary vascular resistance (PVR) leading to right ventricular (RV) failure. Although several drugs are approved for the treatment of PAH, mortality remains high. Accumulating evidence supports a pathological function of integrins in vessel remodeling, which are gaining renewed interest as drug targets. However, their role in PAH remains largely unexplored. We found that the arginine-glycine-aspartate (RGD)-binding integrin α5ß1 is upregulated in PA endothelial cells (PAEC) and PA smooth muscle cells (PASMC) from PAH patients and remodeled PAs from animal models. Blockade of the integrin α5ß1 or depletion of the α5 subunit resulted in mitotic defects and inhibition of the pro-proliferative and apoptosis-resistant phenotype of PAH cells. Using a novel small molecule integrin inhibitor and neutralizing antibodies, we demonstrated that α5ß1 integrin blockade attenuates pulmonary vascular remodeling and improves hemodynamics and RV function in multiple preclinical models. Our results provide converging evidence to consider α5ß1 integrin inhibition as a promising therapy for pulmonary hypertension. One sentence summary: The α5ß1 integrin plays a crucial role in pulmonary vascular remodeling.

2.
Am J Respir Crit Care Med ; 209(11): 1376-1391, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38261723

RESUMO

Rationale: The ubiquitous polyamine spermidine is essential for cell survival and proliferation. One important function of spermidine is to serve as a substrate for hypusination, a posttranslational modification process that occurs exclusively on eukaryotic translation factor 5A (eIF5A) and ensures efficient translation of various gene products. Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by progressive obliteration of the small pulmonary arteries (PAs) caused by excessive proliferation of PA smooth muscle cells (PASMCs) and suppressed apoptosis. Objectives: To characterize the role of hypusine signaling in PAH. Methods: Molecular, genetic, and pharmacological approaches were used both in vitro and in vivo to investigate the role of hypusine signaling in pulmonary vascular remodeling. Measurements and Main Results: Hypusine forming enzymes-deoxyhypusine synthase (DHPS) and deoxyhypusine hydroxylase (DOHH)-and hypusinated eukaryotic translation factor 5A are overexpressed in distal PAs and isolated PASMCs from PAH patients and animal models. In vitro, inhibition of DHPS using N1-guanyl-1,7-diaminoheptane or shRNA resulted in a decrease in PAH-PASMC resistance to apoptosis and proliferation. In vivo, inactivation of one allele of Dhps targeted to smooth muscle cells alleviates PAH in mice, and its pharmacological inhibition significantly decreases pulmonary vascular remodeling and improves hemodynamics and cardiac function in two rat models of established PAH. With mass spectrometry, hypusine signaling is shown to promote the expression of a broad array of proteins involved in oxidative phosphorylation, thus supporting the bioenergetic requirements of cell survival and proliferation. Conclusions: These findings support inhibiting hypusine signaling as a potential treatment for PAH.


Assuntos
Hipertensão Arterial Pulmonar , Transdução de Sinais , Remodelação Vascular , Animais , Remodelação Vascular/efeitos dos fármacos , Remodelação Vascular/fisiologia , Ratos , Humanos , Hipertensão Arterial Pulmonar/fisiopatologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Hipertensão Arterial Pulmonar/metabolismo , Masculino , Modelos Animais de Doenças , Artéria Pulmonar/fisiopatologia , Artéria Pulmonar/efeitos dos fármacos , Camundongos , Fatores de Iniciação de Peptídeos/metabolismo , Fatores de Iniciação de Peptídeos/genética , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A , Proliferação de Células/efeitos dos fármacos , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/metabolismo , Lisina/análogos & derivados
3.
Br J Pharmacol ; 180(1): 94-110, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36068079

RESUMO

BACKGROUND AND PURPOSE: Capillary arterialization, characterized by the coverage of pre-existing or nascent capillary vessels with vascular smooth muscle cells (VSMCs), is critical for the development of collateral arterioles to improve post-ischaemic blood flow. We previously demonstrated that the inhibition of transient receptor potential 6 subfamily C, member 6 (TRPC6) channels facilitate contractile differentiation of VSMCs under ischaemic stress. We here investigated whether TRPC6 inhibition promotes post-ischaemic blood flow recovery through capillary arterialization in vivo. EXPERIMENTAL APPROACH: Mice were subjected to hindlimb ischaemia by ligating left femoral artery. The recovery rate of peripheral blood flow was calculated by the ratio of ischaemic left leg to non-ischaemic right one. The number and diameter of blood vessels were analysed by immunohistochemistry. Expression and phosphorylation levels of TRPC6 proteins were determined by western blotting and immunohistochemistry. KEY RESULTS: Although the post-ischaemic blood flow recovery is reportedly dependent on endothelium-dependent relaxing factors, systemic TRPC6 deletion significantly promoted blood flow recovery under the condition that nitric oxide or prostacyclin production were inhibited, accompanying capillary arterialization. Cilostazol, a clinically approved drug for peripheral arterial disease, facilitates blood flow recovery by inactivating TRPC6 via phosphorylation at Thr69 in VSMCs. Furthermore, inhibition of TRPC6 channel activity by pyrazole-2 (Pyr2; BTP2; YM-58483) promoted post-ischaemic blood flow recovery in Apolipoprotein E-knockout mice. CONCLUSION AND IMPLICATIONS: Suppression of TRPC6 channel activity in VSMCs could be a new strategy for the improvement of post-ischaemic peripheral blood circulation.


Assuntos
Canais de Potencial de Receptor Transitório , Camundongos , Animais , Isquemia/metabolismo , Miócitos de Músculo Liso/metabolismo , Canal de Cátion TRPC6 , Camundongos Knockout , Canais de Cátion TRPC/metabolismo
4.
Cells ; 11(13)2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35805125

RESUMO

Retarded revascularization after progressive occlusion of large conductance arteries is a major cause of bad prognosis for peripheral artery disease (PAD). However, pharmacological treatment for PAD is still limited. We previously reported that suppression of transient receptor potential canonical (TRPC) 6 channel activity in vascular smooth muscle cells (VSMCs) facilitates VSMC differentiation without affecting proliferation and migration. In this study, we found that 1-benzilpiperadine derivative (1-BP), a selective inhibitor for TRPC3 and TRPC6 channel activities, induced VSMC differentiation. 1-BP-treated mice showed increased capillary arterialization and improvement of peripheral circulation and skeletal muscle mass after hind-limb ischemia (HLI) in mice. 1-BP had no additive effect on the facilitation of blood flow recovery after HLI in TRPC6-deficient mice, suggesting that suppression of TRPC6 underlies facilitation of the blood flow recovery by 1-BP. 1-BP also improved vascular nitric oxide bioavailability and blood flow recovery after HLI in hypercholesterolemic mice with endothelial dysfunction, suggesting the retrograde interaction from VSMCs to endothelium. These results suggest that 1-BP becomes a potential seed for PAD treatments that target vascular TRPC6 channels.


Assuntos
Isquemia , Miócitos de Músculo Liso , Canais de Cátion TRPC/metabolismo , Canal de Cátion TRPC6/metabolismo , Animais , Artérias , Isquemia/tratamento farmacológico , Camundongos , Músculo Esquelético
5.
JACC Basic Transl Sci ; 7(4): 384-403, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35540097

RESUMO

The authors show that increased poly(adenosine diphosphate-ribose) polymerase 1 (PARP1) and pyruvate kinase muscle isozyme 2 (PKM2) expression is a common feature of a decompensated right ventricle in patients with pulmonary arterial hypertension and animal models. The authors find in vitro that overactivated PARP1 promotes cardiomyocyte dysfunction by favoring PKM2 expression and nuclear function, glycolytic gene expression, activation of nuclear factor κB-dependent proinflammatory factors. Pharmacologic and genetic inhibition of PARP1 or enforced tetramerization of PKM2 attenuates maladaptive remodeling improving right ventricular (RV) function in multiple rodent models. Taken together, these data implicate the PARP1/PKM2 axis as a critical driver of maladaptive RV remodeling and a new promising target to directly sustain RV function in patients with pulmonary arterial hypertension.

6.
Thorax ; 77(3): 247-258, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34226205

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterised by exuberant tissue remodelling and associated with high unmet medical needs. Outcomes are even worse when IPF results in secondary pulmonary hypertension (PH). Importantly, exaggerated resistance to cell death, excessive proliferation and enhanced synthetic capacity are key endophenotypes of both fibroblasts and pulmonary artery smooth muscle cells, suggesting shared molecular pathways. Under persistent injury, sustained activation of the DNA damage response (DDR) is integral to the preservation of cells survival and their capacity to proliferate. Checkpoint kinases 1 and 2 (CHK1/2) are key components of the DDR. The objective of this study was to assess the role of CHK1/2 in the development and progression of IPF and IPF+PH. METHODS AND RESULTS: Increased expression of DNA damage markers and CHK1/2 were observed in lungs, remodelled pulmonary arteries and isolated fibroblasts from IPF patients and animal models. Blockade of CHK1/2 expression or activity-induced DNA damage overload and reverted the apoptosis-resistant and fibroproliferative phenotype of disease cells. Moreover, inhibition of CHK1/2 was sufficient to interfere with transforming growth factor beta 1-mediated fibroblast activation. Importantly, pharmacological inhibition of CHK1/2 using LY2606368 attenuated fibrosis and pulmonary vascular remodelling leading to improvement in respiratory mechanics and haemodynamic parameters in two animal models mimicking IPF and IPF+PH. CONCLUSION: This study identifies CHK1/2 as key regulators of lung fibrosis and provides a proof of principle for CHK1/2 inhibition as a potential novel therapeutic option for IPF and IPF+PH.


Assuntos
Hipertensão Pulmonar , Fibrose Pulmonar Idiopática , Animais , Fibroblastos/metabolismo , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Miócitos de Músculo Liso/metabolismo
7.
JA Clin Rep ; 7(1): 72, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34585308

RESUMO

BACKGROUND: Neurotoxicity caused by a local anesthetic after regional anesthesia is a rare but serious problem for anesthesiologists. It is difficult to diagnose neurotoxicity from anesthetics because of the large number of possible diagnoses. In this case report, careful monitoring by neurological examinations helped to diagnose local neurotoxicity caused after epidural anesthesia. CASE DESCRIPTION: A 41-year-old pregnant woman who underwent emergency cesarean delivery under combined spinal-epidural anesthesia suffered left leg paralysis after surgery. Multiple neurological examinations (e.g., electromyography, nerve conduction study) revealed that the paralysis was induced by the neurotoxicity of ropivacaine. The neurological examinations were also useful to monitor the recovery process. CONCLUSIONS: This is the first clinical case report that describes the diagnosis of and recovery from local anesthesia-induced neurotoxicity monitored by electromyography and nerve conduction study. Neurological disorders caused by regional anesthetics should be carefully examined and diagnosed using these neurological examinations.

8.
Cells ; 10(6)2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208388

RESUMO

Pulmonary arterial hypertension is a debilitating chronic disorder marked by the progressive obliteration of the pre-capillary arterioles. This imposes a pressure overload on the right ventricle (RV) pushing the latter to undergo structural and mechanical adaptations that inexorably culminate in RV failure and death. Thanks to the advances in molecular biology, it has been proposed that some aspects of the RV and pulmonary vascular remodeling processes are orchestrated by a subversion of developmental regulatory mechanisms with an upregulation of a suite of genes responsible for the embryo's early growth and normally repressed in adults. In this review, we present relevant background regarding the close relationship between overactivation of fetal genes and cardiopulmonary remodeling, exploring whether the reawakening of developmental factors plays a causative role or constitutes a protective mechanism in the setting of PAH.


Assuntos
Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes , Hipertensão Arterial Pulmonar/prevenção & controle , Animais , Humanos , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia
9.
Am J Respir Crit Care Med ; 203(5): 614-627, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33021405

RESUMO

Rationale: Pulmonary arterial hypertension (PAH) is a life-threatening condition characterized by abnormally elevated pulmonary pressures and right ventricular failure. Excessive proliferation and resistance to apoptosis of pulmonary artery smooth muscle cells (PASMCs) is one of the most important drivers of vascular remodeling in PAH, for which available treatments have limited effectiveness.Objectives: To gain insights into the mechanisms leading to the development of the disease and identify new actionable targets.Methods: Protein expression profiling was conducted by two-dimensional liquid chromatography coupled to tandem mass spectrometry in isolated PASMCs from controls and patients with PAH. Multiple molecular, biochemical, and pharmacologic approaches were used to decipher the role of NUDT1 (nudrix hyrolase 1) in PAH.Measurements and Main Results: Increased expression of the detoxifying DNA enzyme NUDT1 was detected in cells and tissues from patients with PAH and animal models. In vitro, molecular or pharmacological inhibition of NUDT1 in PAH-PASMCs induced accumulation of oxidized nucleotides in the DNA, irresolvable DNA damage (comet assay), disruption of cellular bioenergetics (Seahorse), and cell death (terminal deoxynucleotidyl transferase dUTP nick end labeling assay). In two animal models with established PAH (i.e., monocrotaline and Sugen/hypoxia-treated rats), pharmacological inhibition of NUDT1 using (S)-Crizotinib significantly decreased pulmonary vascular remodeling and improved hemodynamics and cardiac function.Conclusions: Our results indicate that, by overexpressing NUDT1, PAH-PASMCs hijack persistent oxidative stress in preventing incorporation of oxidized nucleotides into DNA, thus allowing the cell to escape apoptosis and proliferate. Given that NUDT1 inhibitors are under clinical investigation for cancer, they may represent a new therapeutic option for PAH.


Assuntos
Enzimas Reparadoras do DNA/genética , DNA/metabolismo , Estresse Oxidativo/genética , Monoéster Fosfórico Hidrolases/genética , Hipertensão Arterial Pulmonar/genética , Artéria Pulmonar/metabolismo , Remodelação Vascular/genética , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Adulto , Idoso , Animais , Apoptose/genética , Western Blotting , Estudos de Casos e Controles , Proliferação de Células/genética , Cromatografia Líquida , Ensaio Cometa , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/metabolismo , Modelos Animais de Doenças , Feminino , Proteína Forkhead Box M1/metabolismo , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Oxirredução , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , Pirofosfatases/antagonistas & inibidores , Pirofosfatases/genética , Pirofosfatases/metabolismo , RNA Mensageiro/metabolismo , Ratos , Espectrometria de Massas em Tandem , Regulação para Cima
10.
Cardiovasc Diagn Ther ; 10(5): 1735-1767, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33224787

RESUMO

Therapeutic options for right ventricular (RV) dysfunction and failure are strongly limited. Right heart failure (RHF) has been mostly addressed in the context of pulmonary arterial hypertension (PAH), where it is not possible to discern pulmonary vascular- and RV-directed effects of therapeutic approaches. In part, opposing pathomechanisms in RV and pulmonary vasculature, i.e., regarding apoptosis, angiogenesis and proliferation, complicate addressing RHF in PAH. Therapy effective for left heart failure is not applicable to RHF, e.g., inhibition of adrenoceptor signaling and of the renin-angiotensin system had no or only limited success. A number of experimental studies employing animal models for PAH or RV dysfunction or failure have identified beneficial effects of novel pharmacological agents, with most promising results obtained with modulators of metabolism and reactive oxygen species or inflammation, respectively. In addition, established PAH agents, in particular phosphodiesterase-5 inhibitors and soluble guanylate cyclase stimulators, may directly address RV integrity. Promising results are furthermore derived with microRNA (miRNA) and long non-coding RNA (lncRNA) blocking or mimetic strategies, which can target microvascular rarefaction, inflammation, metabolism or fibrotic and hypertrophic remodeling in the dysfunctional RV. Likewise, pre-clinical data demonstrate that cell-based therapies using stem or progenitor cells have beneficial effects on the RV, mainly by improving the microvascular system, however clinical success will largely depend on delivery routes. A particular option for PAH is targeted denervation of the pulmonary vasculature, given the sympathetic overdrive in PAH patients. Finally, acute and durable mechanical circulatory support are available for the right heart, which however has been tested mostly in RHF with concomitant left heart disease. Here, we aim to review current pharmacological, RNA- and cell-based therapeutic options and their potential to directly target the RV and to review available data for pulmonary artery denervation and mechanical circulatory support.

11.
Circulation ; 142(15): 1464-1484, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32698630

RESUMO

BACKGROUND: Right ventricular (RV) function is the major determinant for both functional capacity and survival in patients with pulmonary arterial hypertension (PAH). Despite the recognized clinical importance of preserving RV function, the subcellular mechanisms that govern the transition from a compensated to a decompensated state remain poorly understood and as a consequence there are no clinically established treatments for RV failure and a paucity of clinically useful biomarkers. Accumulating evidence indicates that long noncoding RNAs are powerful regulators of cardiac development and disease. Nonetheless, their implication in adverse RV remodeling in PAH is unknown. METHODS: Expression of the long noncoding RNA H19 was assessed by quantitative PCR in plasma and RV from patients categorized as control RV, compensated RV or decompensated RV based on clinical history and cardiac index. The impact of H19 suppression using GapmeR was explored in 2 rat models mimicking RV failure, namely the monocrotaline and pulmonary artery banding. Echocardiographic, hemodynamic, histological, and biochemical analyses were conducted. In vitro gain- and loss-of-function experiments were performed in rat cardiomyocytes. RESULTS: We demonstrated that H19 is upregulated in decompensated RV from PAH patients and correlates with RV hypertrophy and fibrosis. Similar findings were observed in monocrotaline and pulmonary artery banding rats. We found that silencing H19 limits pathological RV hypertrophy, fibrosis and capillary rarefaction, thus preserving RV function in monocrotaline and pulmonary artery banding rats without affecting pulmonary vascular remodeling. This cardioprotective effect was accompanied by E2F transcription factor 1-mediated upregulation of enhancer of zeste homolog 2. In vitro, knockdown of H19 suppressed cardiomyocyte hypertrophy induced by phenylephrine, while its overexpression has the opposite effect. Finally, we demonstrated that circulating H19 levels in plasma discriminate PAH patients from controls, correlate with RV function and predict long-term survival in 2 independent idiopathic PAH cohorts. Moreover, H19 levels delineate subgroups of patients with differentiated prognosis when combined with the NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels or the risk score proposed by both REVEAL (Registry to Evaluate Early and Long-Term PAH Disease Management) and the 2015 European Pulmonary Hypertension Guidelines. CONCLUSIONS: Our findings identify H19 as a new therapeutic target to impede the development of maladaptive RV remodeling and a promising biomarker of PAH severity and prognosis.


Assuntos
Insuficiência Cardíaca/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , RNA Longo não Codificante/metabolismo , Remodelação Vascular , Disfunção Ventricular Direita/metabolismo , Animais , Biomarcadores/metabolismo , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/patologia , Humanos , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Hipertensão Arterial Pulmonar/mortalidade , Hipertensão Arterial Pulmonar/patologia , Ratos , Disfunção Ventricular Direita/mortalidade , Disfunção Ventricular Direita/patologia
12.
FASEB J ; 33(9): 9785-9796, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31162976

RESUMO

Vascular smooth muscle cells (VSMCs) play critical roles in the stability and tonic regulation of vascular homeostasis. VSMCs can switch back and forth between highly proliferative synthetic and fully differentiated contractile phenotypes in response to changes in the vessel environment. Although abnormal phenotypic switching of VSMCs is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty, how control of VSMC phenotypic switching is dysregulated in pathologic conditions remains obscure. We found that inhibition of canonical transient receptor potential 6 (TRPC6) channels facilitated contractile differentiation of VSMCs through plasma membrane hyperpolarization. TRPC6-deficient VSMCs exhibited more polarized resting membrane potentials and higher protein kinase B (Akt) activity than wild-type VSMCs in response to TGF-ß1 stimulation. Ischemic stress elicited by oxygen-glucose deprivation suppressed TGF-ß1-induced hyperpolarization and VSMC differentiation, but this effect was abolished by TRPC6 deletion. TRPC6-mediated Ca2+ influx and depolarization coordinately promoted the interaction of TRPC6 with lipid phosphatase and tensin homolog deleted from chromosome 10 (PTEN), a negative regulator of Akt activation. Given the marked up-regulation of TRPC6 observed in vascular disorders, our findings suggest that attenuation of TRPC6 channel activity in pathologic VSMCs could be a rational strategy to maintain vascular quality control by fine-tuning of VSMC phenotypic switching.-Numaga-Tomita, T., Shimauchi, T., Oda, S., Tanaka, T., Nishiyama, K., Nishimura, A., Birnbaumer, L., Mori, Y., Nishida, M. TRPC6 regulates phenotypic switching of vascular smooth muscle cells through plasma membrane potential-dependent coupling with PTEN.


Assuntos
Potenciais da Membrana/fisiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Canal de Cátion TRPC6/metabolismo , Animais , Aorta , Linhagem Celular , Membrana Celular , Camundongos , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Canal de Cátion TRPC6/genética
13.
Sci Signal ; 11(556)2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30425165

RESUMO

Defective mitochondrial dynamics through aberrant interactions between mitochondria and actin cytoskeleton is increasingly recognized as a key determinant of cardiac fragility after myocardial infarction (MI). Dynamin-related protein 1 (Drp1), a mitochondrial fission-accelerating factor, is activated locally at the fission site through interactions with actin. Here, we report that the actin-binding protein filamin A acted as a guanine nucleotide exchange factor for Drp1 and mediated mitochondrial fission-associated myocardial senescence in mice after MI. In peri-infarct regions characterized by mitochondrial hyperfission and associated with myocardial senescence, filamin A colocalized with Drp1 around mitochondria. Hypoxic stress induced the interaction of filamin A with the GTPase domain of Drp1 and increased Drp1 activity in an actin-binding-dependent manner in rat cardiomyocytes. Expression of the A1545T filamin mutant, which potentiates actin aggregation, promoted mitochondrial hyperfission under normoxia. Furthermore, pharmacological perturbation of the Drp1-filamin A interaction by cilnidipine suppressed mitochondrial hyperfission-associated myocardial senescence and heart failure after MI. Together, these data demonstrate that Drp1 association with filamin and the actin cytoskeleton contributes to cardiac fragility after MI and suggests a potential repurposing of cilnidipine, as well as provides a starting point for innovative Drp1 inhibitor development.


Assuntos
Dinaminas/metabolismo , Filaminas/metabolismo , Dinâmica Mitocondrial , Miocárdio/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Cateterismo Cardíaco , Hipóxia Celular , Senescência Celular , Di-Hidropiridinas/farmacologia , Ecocardiografia , Guanosina Trifosfato/química , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Infarto do Miocárdio/tratamento farmacológico , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
14.
JA Clin Rep ; 4(1): 79, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-32026013

RESUMO

BACKGROUND: Arginine vasopressin has been used for the management of refractory vasodilatory shock. However, it is still unclear whether arginine vasopressin is useful for hypotension in patients with spinal cord injury. CASE DESCRIPTION: A 78-year-old man with autonomic dysreflexia and paralysis below the level corresponding to Th2 due to spinal cord injury previously underwent cholecystectomy. During the surgery, accidental hemorrhage led him to refractory hemorrhagic shock unresponsive to fluid resuscitation and catecholamine. Lasting hypotension was improved with arginine vasopressin. CONCLUSION: We described a rare case report on the use of arginine vasopressin for management of refractory hemorrhagic shock in a patient with autonomic dysreflexia.

15.
Front Cardiovasc Med ; 4: 56, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28936433

RESUMO

Cardiac stiffness, caused by interstitial fibrosis due to deposition of extracellular matrix proteins, is thought as a major clinical outcome of heart failure with preserved ejection fraction (HFpEF). Canonical transient receptor potential (TRPC) subfamily proteins are components of Ca2+-permeable non-selective cation channels activated by receptor stimulation and mechanical stress, and have been attracted attention as a key mediator of maladaptive cardiac remodeling. How TRPC-mediated local Ca2+ influx encodes a specific signal to induce maladaptive cardiac remodeling has been long obscure, but our recent studies suggest a pathophysiological significance of channel activity-independent function of TRPC proteins for amplifying redox signaling in heart. This review introduces the current understanding of the physiological and pathophysiological roles of TRPCs, especially focuses on the role of TRPC3 as a positive regulator of reactive oxygen species (PRROS) in heart. We have revealed that TRPC3 stabilizes NADPH oxidase 2 (Nox2), a membrane-bound reactive oxygen species (ROS)-generating enzyme, by forming stable protein complex with Nox2, which leads to amplification of mechanical stress-induced ROS signaling in cardiomyocytes, resulting in induction of fibrotic responses in cardiomyocytes and cardiac fibroblasts. Thus, the TRPC3 function as PRROS will offer a new therapeutic strategy for the prevention or treatment of HFpEF.

16.
Sci Rep ; 7(1): 7511, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790356

RESUMO

Excess production of reactive oxygen species (ROS) caused by hyperglycemia is a major risk factor for heart failure. We previously reported that transient receptor potential canonical 3 (TRPC3) channel mediates pressure overload-induced maladaptive cardiac fibrosis by forming stably functional complex with NADPH oxidase 2 (Nox2). Although TRPC3 has been long suggested to form hetero-multimer channels with TRPC6 and function as diacylglycerol-activated cation channels coordinately, the role of TRPC6 in heart is still obscure. We here demonstrated that deletion of TRPC6 had no impact on pressure overload-induced heart failure despite inhibiting interstitial fibrosis in mice. TRPC6-deficient mouse hearts 1 week after transverse aortic constriction showed comparable increases in fibrotic gene expressions and ROS production but promoted inductions of inflammatory cytokines, compared to wild type hearts. Treatment of TRPC6-deficient mice with streptozotocin caused severe reduction of cardiac contractility with enhancing urinary and cardiac lipid peroxide levels, compared to wild type and TRPC3-deficient mice. Knockdown of TRPC6, but not TRPC3, enhanced basal expression levels of cytokines in rat cardiomyocytes. TRPC6 could interact with Nox2, but the abundance of TRPC6 was inversely correlated with that of Nox2. These results strongly suggest that Nox2 destabilization through disrupting TRPC3-Nox2 complex underlies attenuation of hyperglycemia-induced heart failure by TRPC6.


Assuntos
Diabetes Mellitus Experimental/genética , Insuficiência Cardíaca/genética , Hiperglicemia/genética , NADPH Oxidase 2/genética , Canais de Cátion TRPC/genética , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Regulação da Expressão Gênica , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Hiperglicemia/induzido quimicamente , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Peróxidos Lipídicos/metabolismo , Camundongos , Camundongos Knockout , Contração Miocárdica , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NADPH Oxidase 2/metabolismo , Cultura Primária de Células , Ligação Proteica , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Estreptozocina , Canais de Cátion TRPC/deficiência , Canal de Cátion TRPC6
17.
JCI Insight ; 2(15)2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28768915

RESUMO

Myocardial atrophy is a wasting of cardiac muscle due to hemodynamic unloading. Doxorubicin is a highly effective anticancer agent but also induces myocardial atrophy through a largely unknown mechanism. Here, we demonstrate that inhibiting transient receptor potential canonical 3 (TRPC3) channels abolishes doxorubicin-induced myocardial atrophy in mice. Doxorubicin increased production of ROS in rodent cardiomyocytes through hypoxic stress-mediated upregulation of NADPH oxidase 2 (Nox2), which formed a stable complex with TRPC3. Cardiomyocyte-specific expression of TRPC3 C-terminal minipeptide inhibited TRPC3-Nox2 coupling and suppressed doxorubicin-induced reduction of myocardial cell size and left ventricular (LV) dysfunction, along with its upregulation of Nox2 and oxidative stress, without reducing hypoxic stress. Voluntary exercise, an effective treatment to prevent doxorubicin-induced cardiotoxicity, also downregulated the TRPC3-Nox2 complex and promoted volume load-induced LV compliance, as demonstrated in TRPC3-deficient hearts. These results illustrate the impact of TRPC3 on LV compliance and flexibility and, focusing on the TRPC3-Nox2 complex, provide a strategy for prevention of doxorubicin-induced cardiomyopathy.

19.
Sci Signal ; 9(411): ra7, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26787451

RESUMO

The angiotensin (Ang) type 1 receptor (AT1R) promotes functional and structural integrity of the arterial wall to contribute to vascular homeostasis, but this receptor also promotes hypertension. In our investigation of how Ang II signals are converted by the AT1R from physiological to pathological outputs, we found that the purinergic P2Y6 receptor (P2Y6R), an inflammation-inducible G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptor (GPCR), promoted Ang II-induced hypertension in mice. In mice, deletion of P2Y6R attenuated Ang II-induced increase in blood pressure, vascular remodeling, oxidative stress, and endothelial dysfunction. AT1R and P2Y6R formed stable heterodimers, which enhanced G protein-dependent vascular hypertrophy but reduced ß-arrestin-dependent AT1R internalization. Pharmacological disruption of AT1R-P2Y6R heterodimers by the P2Y6R antagonist MRS2578 suppressed Ang II-induced hypertension in mice. Furthermore, P2Y6R abundance increased with age in vascular smooth muscle cells. The increased abundance of P2Y6R converted AT1R-stimulated signaling in vascular smooth muscle cells from ß-arrestin-dependent proliferation to G protein-dependent hypertrophy. These results suggest that increased formation of AT1R-P2Y6R heterodimers with age may increase the likelihood of hypertension induced by Ang II.


Assuntos
Envelhecimento/metabolismo , Angiotensina II/efeitos adversos , Hipertensão/metabolismo , Multimerização Proteica/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores Purinérgicos P2/metabolismo , Envelhecimento/genética , Angiotensina II/farmacologia , Animais , Células HEK293 , Humanos , Hipertensão/induzido quimicamente , Hipertensão/genética , Camundongos , Camundongos Knockout , Multimerização Proteica/genética , Receptor Tipo 1 de Angiotensina/genética , Receptores Purinérgicos P2/genética
20.
Mol Endocrinol ; 30(1): 118-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26652903

RESUMO

Insulin resistance is a condition in which cells are defective in response to the actions of insulin in tissue glucose uptake. Overstimulation of ß-adrenergic receptors (ßARs) leads to the development of heart failure and is associated with the pathogenesis of insulin resistance in the heart. However, the mechanisms by which sustained ßAR stimulation affects insulin resistance in the heart are incompletely understood. In this study, we demonstrate that sustained ßAR stimulation resulted in the inhibition of insulin-induced glucose uptake, and a reduction of insulin induced glucose transporter (GLUT)4 expression that were mediated by the ß2AR subtype in cardiomyocytes and heart tissue. Overstimulation of ß2AR inhibited the insulin-induced translocation of GLUT4 to the plasma membrane of cardiomyocytes. Additionally, ßAR mediated cardiac insulin resistance by reducing glucose uptake and GLUT4 expression via the cAMP-dependent and protein kinase A-dependent pathways. Treatment with ß-blockers, including propranolol and metoprolol antagonized isoproterenol-mediated insulin resistance in the heart. The data in this present study confirm a critical role for protein kinase A in ßAR-mediated insulin resistance.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Resistência à Insulina/fisiologia , Miocárdio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Animais , Células HEK293 , Humanos , Isoproterenol/farmacologia , Metoprolol/farmacologia , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Propranolol/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos
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