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1.
Artigo em Inglês | MEDLINE | ID: mdl-38866609

RESUMO

BACKGROUND AND AIMS: Limited evidence exist regarding the association between ongericimab, a novel recombinant humanized anti-PCSK9 monoclonal antibody, and primary hypercholesterolemia and mixed dyslipidemia. This study aimed to evaluate the efficacy and safety of ongericimab administered by prefilled syringe (PFS) or autoinjector (AI) in Chinese patients with primary hypercholesterolemia and mixed dyslipidemia on stable optimized lipid-lowering therapy. METHODS AND RESULTS: A total of 255 patients on stable optimized lipid-lowering therapy were randomized in a 2:1:2:1 ratio to receive PFS for the subcutaneous injection of ongericimab 150 mg every 2 weeks (Q2W) or a matching placebo, or AI for the subcutaneous injection of ongericimab 150 mg Q2W or a matching placebo. The primary efficacy endpoint was the percent change in low-density lipoprotein cholesterol (LDL-C) levels from baseline to week 12. Safety was also evaluated. At week 12, the least squares mean percent changes were -72.7% (3.9%) for PFS and -71.1% (3.8%) for AI (all P < 0.001) compared to respective matching placebo groups. Beneficial effects were also seen for all secondary lipid parameters, notably with robust reduction in Lp (a). Treatment-emergent adverse events (TEAEs) and serious AEs with ongericimab were reported in 46.2% and 2.4% of patients, compared to 44.2% and 3.5% with placebo. CONCLUSION: In Chinese patients with primary hypercholesterolemia and mixed dyslipidemia, a 12-week treatment regimen with ongericimab administered by PFS or AI significantly reduced LDL-C and other lipid parameters, proving to be safe and well tolerated. Patients experienced consistent effects from PFS or AI devices. CLINICAL TRIAL REGISTRATION: CTR20220027; January 11, 2022; http://www.chinadrugtrials.org.cn/index.html.

2.
Acta Pharmacol Sin ; 43(1): 39-49, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33767380

RESUMO

Alzheimer's disease (AD) is associated with high incidence of cardiovascular events but the mechanism remains elusive. Our previous study reveals a tight correlation between cardiac dysfunction and low mitochondrial aldehyde dehydrogenase (ALDH2) activity in elderly AD patients. In the present study we investigated the effect of ALDH2 overexpression on cardiac function in APP/PS1 mouse model of AD. Global ALDH2 transgenic mice were crossed with APP/PS1 mutant mice to generate the ALDH2-APP/PS1 mutant mice. Cognitive function, cardiac contractile, and morphological properties were assessed. We showed that APP/PS1 mice displayed significant cognitive deficit in Morris water maze test, myocardial ultrastructural, geometric (cardiac atrophy, interstitial fibrosis) and functional (reduced fractional shortening and cardiomyocyte contraction) anomalies along with oxidative stress, apoptosis, and inflammation in myocardium. ALDH2 transgene significantly attenuated or mitigated these anomalies. We also noted the markedly elevated levels of lipid peroxidation, the essential lipid peroxidation enzyme acyl-CoA synthetase long-chain family member 4 (ACSL4), the transcriptional regulator for ACLS4 special protein 1 (SP1) and ferroptosis, evidenced by elevated NCOA4, decreased GPx4, and SLC7A11 in myocardium of APP/PS1 mutant mice; these effects were nullified by ALDH2 transgene. In cardiomyocytes isolated from WT mice and in H9C2 myoblasts in vitro, application of Aß (20 µM) decreased cell survival, compromised cardiomyocyte contractile function, and induced lipid peroxidation; ALDH2 transgene or activator Alda-1 rescued Aß-induced deteriorating effects. ALDH2-induced protection against Aß-induced lipid peroxidation was mimicked by the SP1 inhibitor tolfenamic acid (TA) or the ACSL4 inhibitor triacsin C (TC), and mitigated by the lipid peroxidation inducer 5-hydroxyeicosatetraenoic acid (5-HETE) or the ferroptosis inducer erastin. These results demonstrate an essential role for ALDH2 in AD-induced cardiac anomalies through regulation of lipid peroxidation and ferroptosis.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Coenzima A Ligases/metabolismo , Modelos Animais de Doenças , Presenilina-1/metabolismo , Doença de Alzheimer/patologia , Animais , Relação Dose-Resposta a Droga , Ferroptose , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Contração Miocárdica , Relação Estrutura-Atividade
3.
J Mol Cell Cardiol ; 148: 78-88, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32891637

RESUMO

Second-hand smoking evokes inflammation and cardiovascular diseases. Recent evidence has revealed a pivotal role for deranged autophagy in smoke exposure-induced cardiac anomalies. This study evaluated the impact of haploinsufficiency of the mTOR-independent autophagy protein Beclin1 on side-stream smoke exposure-induced cardiac anomalies and mechanism(s) involved. Adult WT and Beclin1 haploinsufficiency (Becn+/-) mice were exposed to cigarette smoke for 1 h daily for 90 days. Echocardiographic, cardiomyocyte function, intracellular Ca2+, autophagy, mitophagy, apoptosis and inflammation were examined. DHE staining was employed to evaluate O2- level. Our data revealed that Beclin1 deficiency exacerbated smoke exposure-induced myocardial anomalies in geometry, fractional shortening, cardiomyocyte function, intracellular Ca2+ handling, TEM ultrastructure, and inflammation along with pronounced apoptosis and O2- production. Side-stream smoke provoked excessive autophagy/mitophagy, mtDNA release, and activation of innate immune response signals cyclic GMP-AMP synthase (cGAS) and its effector - stimulator of interferon genes (STING), the effect was abolished or unaffected by Becn haploinsufficiency. STING phosphorylation was overtly promoted by smoke exposure in Becn+/- mice. Smoke exposure also suppressed phosphorylation of mTOR although it facilitated that of ULK1 in both groups. In vitro data revealed that inhibition of cGAS or STING failed to affect smoke extract-induced mitophagy although they abrogated smoke extract-induced cardiomyocyte dysfunction except cGAS inhibition in Becn+/- mice. These data suggest that Beclin1 is integral in the maintenance of cardiac homeostasis under side-stream smoke exposure via a STING-mediated mechanism.


Assuntos
Proteína Beclina-1/genética , Haploinsuficiência/genética , Proteínas de Membrana/metabolismo , Contração Miocárdica , Miocárdio/patologia , Poluição por Fumaça de Tabaco , Remodelação Ventricular , Animais , Animais Recém-Nascidos , Apoptose , Autofagia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteína Beclina-1/deficiência , Biomarcadores/metabolismo , Fenômenos Biomecânicos , DNA Mitocondrial/metabolismo , Eletrocardiografia , Inflamação/patologia , Camundongos , Mitofagia , Miocárdio/ultraestrutura , Miócitos Cardíacos/metabolismo , Nucleotidiltransferases/metabolismo , Biogênese de Organelas , Fosforilação , Transdução de Sinais , Superóxidos/metabolismo , Serina-Treonina Quinases TOR/metabolismo
4.
Noise Health ; 19(88): 149-153, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28615545

RESUMO

INTRODUCTION: Infrasound is a mechanical vibration wave with frequency between 0.0001 and 20 Hz. It has been established that infrasound of 120 dB or stronger is dangerous to humans. However, the biological effects of low decibel infrasound are largely unknown. The purpose of this study was to investigate the effects of low decibel infrasound on the cardiac fibroblasts. MATERIALS AND METHODS: The cardiac fibroblasts were isolated and cultured from Sprague-Dawley rats. The cultured cells were assigned into the following four groups: control group, angiotensin II (Ang II) group, infrasound group, and Ang II+infrasound group. The cell proliferation and collagen synthesis rates were evaluated by means of [3H]-thymidine and [3H]-proline incorporation, respectively. The levels of TGF-ß were determined by enzyme-linked immunosorbent assay. Moreover, RNAi approaches were used for the analysis of the biological functions of miR-29a, and the phosphorylation status of Smad3 was detected using western blotting analysis. RESULTS: The results showed that low decibel infrasound significantly alleviated Ang II-induced enhancement of cell proliferation and collagen synthesis. DISCUSSION: Compared with the control, Ang II markedly decreased the expression of miR-29a levels and increased the secretion of TGF-ß and phosphorylation of Smad3, which was partly reversed by the treatment with low decibel infrasound. Importantly, knockdown of miR-29a diminished the effects of infrasound on the cardiac fibroblasts. In conclusion, low decibel infrasound inhibits Ang II-stimulated cardiac fibroblasts via miR-29a targeting TGF-ß/Smad3 signaling.


Assuntos
Angiotensina II/farmacologia , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Miocárdio/citologia , Vibração , Animais , Células Cultivadas , Colágeno/efeitos dos fármacos , Colágeno/metabolismo , Ensaio de Imunoadsorção Enzimática , Fibroblastos/metabolismo , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , Fosforilação/efeitos dos fármacos , Prolina/efeitos dos fármacos , Prolina/metabolismo , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/efeitos dos fármacos , Proteína Smad3/metabolismo , Timidina/metabolismo , Fator de Crescimento Transformador beta/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Trítio
5.
J Mol Cell Cardiol ; 74: 76-87, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24805195

RESUMO

Lipopolysaccharide (LPS), an essential component of the outer membrane of Gram-negative bacteria, plays a pivotal role in myocardial anomalies in sepsis. Recent evidence has depicted a role of Akt in LPS-induced cardiac sequelae although little information is available with regard to the contribution of Akt isoforms in the endotoxin-induced cardiac dysfunction. This study examined the effect of Akt2 knockout on LPS-induced myocardial contractile dysfunction and the underlying mechanism(s) with a focus on TNF receptor-associated factor 6 (TRAF6). Echocardiographic properties and cardiomyocyte contractile function [peak shortening (PS), maximal velocity of shortening/relengthening, time-to-PS, time-to-90% relengthening] were examined in wild-type and Akt2 knockout mice following LPS challenge (4mg/kg, 4h). LPS challenge enlarged LV end systolic diameter, reduced fractional shortening and cardiomyocyte contractile capacity, prolonged TR90, promoted apoptosis, upregulated caspase-3/-12, ubiquitin, and the ubiquitination E3 ligase TRAF6 as well as decreased mitochondrial membrane potential without affecting the levels of TNF-α, toll-like receptor 4 and the mitochondrial protein ALDH2. Although Akt2 knockout failed to affect myocardial function, apoptosis, and ubiquitination, it significantly attenuated or mitigated LPS-induced changes in cardiac contractile and mitochondrial function, apoptosis and ubiquitination but not TRAF6. LPS facilitated ubiquitination, phosphorylation of Akt, GSK3ß and p38, the effect of which with the exception of p38 was ablated by Akt2 knockout. TRAF6 inhibitory peptide or RNA silencing significantly attenuated LPS-induced Akt2 ubiquitination, cardiac contractile anomalies and apoptosis. These data collectively suggested that TRAF6 may play a pivotal role in mediating LPS-induced cardiac injury via Akt2 ubiquitination.


Assuntos
Cardiomiopatias/genética , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Fator 6 Associado a Receptor de TNF/genética , Ubiquitina/genética , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Aldeído-Desidrogenase Mitocondrial , Animais , Apoptose , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Caspases/genética , Caspases/metabolismo , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Lipopolissacarídeos , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Knockout , Contração Miocárdica , Miocárdio/patologia , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-akt/deficiência , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Pharmacol Res ; 82: 40-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24705155

RESUMO

Recent evidence has suggested that cigarette smoking is associated with an increased prevalence of heart diseases. Given that cigarette smoking triggers proinflammatory response via stimulation of the capsaicin-sensitive transient receptor potential cation channel TRPV1, this study was designed to evaluate the effect of an essential α,ß-unsaturated aldehyde from cigarette smoke crotonaldehyde on myocardial function and the underlying mechanism with a focus on TRPV1 and mitochondria. Cardiomyocyte mechanical and intracellular Ca2+ properties were evaluated including peak shortening (PS), maximal velocity of shortening/relengthening (±dL/dt), time-to-PS (TPS), time-to-90% relengthening (TR90), fura-2 fluorescence intensity (FFI), intracellular Ca2+ decay and SERCA activity. Apoptosis and TRPV1 were evaluated using Western blot analysis. Production of reactive oxygen species (ROS) and DNA damage were measured using the intracellular fluoroprobe 5-(6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate and 8-hydroxy-2'-deoxyguanosine (8-OHdG), respectively. Our data revealed that crotonaldehyde interrupted cardiomyocyte contractile and intracellular Ca2+ property including depressed PS, ±dL/dt, ΔFFI and SERCA activity, as well as prolonged TR90 and intracellular Ca2+ decay. Crotonaldehyde exposure increased TRPV1 and NADPH oxidase levels, promoted apoptosis, mitochondrial injury (decreased aconitase activity, PGC-1α and UCP-2) as well as production of ROS and 8-OHdG. Interestingly, crotonaldehyde-induced cardiac defect was obliterated by the ROS scavenger glutathione and the TRPV1 inhibitor capsazepine. Capsazepine (not glutathione) ablated crotonaldehyde-induced mitochondrial damage. Capsazepine, glutathione and the NADPH inhibitor apocynin negated crotonaldehyde-induced ROS accumulation. Our data suggest a role of crotonaldehyde compromises cardiomyocyte mechanical function possibly through a TRPV1- and mitochondria-dependent oxidative stress mechanism.


Assuntos
Aldeídos/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Aconitato Hidratase/metabolismo , Animais , Cálcio/metabolismo , Caspase 3/metabolismo , Células Cultivadas , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/metabolismo , Contração Miocárdica , Miócitos Cardíacos/fisiologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Fumar
7.
Cardiovasc Toxicol ; 24(2): 85-101, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356081

RESUMO

Cold stress prompts an increased prevalence of cardiovascular morbidity yet the underneath machinery remains unclear. Oxidative stress and autophagy appear to contribute to cold stress-induced cardiac anomalies. Our present study evaluated the effect of heavy metal antioxidant metallothionein on cold stress (4 °C)-induced in cardiac remodeling and contractile anomalies and cell signaling involved including regulation of autophagy and mitophagy. Cold stress (3 weeks) prompted interstitial fibrosis, mitochondrial damage (mitochondrial membrane potential and TEM ultrastructure), oxidative stress (glutathione, reactive oxygen species and superoxide), lipid peroxidation, protein injury, elevated left ventricular (LV) end systolic and diastolic diameters, decreased fractional shortening, ejection fraction, Langendorff heart function, cardiomyocyte shortening, maximal velocities of shortening/relengthening, and electrically stimulated intracellular Ca2+ rise along with elongated relaxation duration and intracellular Ca2+ clearance, the responses of which were overtly attenuated or mitigated by metallothionein. Levels of apoptosis, cell death (Bax and loss of Bcl2, IL-18), and autophagy (LC3BII-to-LC3BI ratio, Atg7 and Beclin-1) were overtly upregulated with comparable p62 under cold stress. Cold stress also evoked elevated mitophagy (decreased TOM20, increased Parkin and FUNDC1 with unaltered BNIP3). Cold stress overtly dampened phosphorylation of autophagy/mitophagy inhibitory molecules Akt and mTOR, stimulated and suppressed phosphorylation of ULK1 and eNOS, respectively, in the absence of altered pan protein levels. Cold stress-evoked responses in cell death, autophagy, mitophagy and their regulatory domains were overtly attenuated or ablated by metallothionein. Suppression of autophagy and mitophagy with 3-methyladenine, bafilomycin A1, cyclosporine A, and liensinine rescued hypothermia-instigated cardiomyocyte LC3B puncta formation and mechanical anomalies. Our findings support a protective nature for metallothionein in deep hypothermia-evoked cardiac abnormalities associated with regulation of autophagy and mitophagy.


Assuntos
Hipotermia , Metais Pesados , Humanos , Mitofagia , Resposta ao Choque Frio , Hipotermia/metabolismo , Metalotioneína , Contração Miocárdica , Miócitos Cardíacos , Autofagia , Metais Pesados/metabolismo , Metais Pesados/farmacologia
8.
Biochim Biophys Acta Gen Subj ; 1867(2): 130281, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36410609

RESUMO

BACKGROUND: Uncorrected obesity facilitates premature aging and cardiovascular anomalies. This study examined the interaction between obesity and aging on cardiac remodeling and contractile function. METHODS: Cardiac echocardiographic geometry, function, morphology, intracellular Ca2+ handling, oxidative stress (DHE fluorescence), STAT3 and stress signaling were evaluated in young (3-mo) and old (12- and 18-mo) lean and leptin deficient ob/ob obese mice. Cardiomyocytes from young and old lean and ob/ob mice were treated with leptin (1 nM) for 4 h in vitro prior to assessment of mechanical and biochemical properties. High fat diet (45% calorie from fat) and the leptin receptor mutant db/db obese mice at young and old age were evaluated for comparison. RESULTS: Our results displayed reduced survival in ob/ob mice. Obesity but less likely older age dampened echocardiographic, geometric, cardiomyocyte function and intracellular Ca2+ properties, elevated O2- and p47phox NADPH oxidase levels with a more pronounced geometric change at older age. Immunoblot analysis revealed elevated p47phox NADPH oxidase and dampened phosphorylation of STAT3, with a more pronounced response in old ob/ob mice, the effects were restored by leptin. Obesity and aging inhibited phosphorylation of Akt, eNOS, AMPK, and p38 while promoting phosphorylation of JNK and IκB. Leptin reconciled cardiomyocyte dysfunction, O2- yield, p47phox upregulation, STAT3 dephosphorylation and stress signaling in ob/ob mice although its action on stress signaling cascades were lost at old age. High fat diet-induced and db/db obesity displayed aging-associated cardiomyocyte anomalies reminiscent of ob/ob model albeit lost leptin response. CONCLUSIONS: Our data suggest disparate age-associated obesity response in cardiac remodeling and contractile dysfunction due to phosphorylation of Akt, eNOS and stress signaling-related oxidative stress.


Assuntos
Envelhecimento , Leptina , Miocárdio , Obesidade , Animais , Camundongos , Leptina/fisiologia , Camundongos Obesos , NADPH Oxidases , Proteínas Proto-Oncogênicas c-akt , Remodelação Ventricular , Miocárdio/patologia , Estresse Oxidativo , Estresse Fisiológico
9.
Life Sci ; 312: 121207, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36403642

RESUMO

Trastuzumab (TZM) is commonly used for target therapy in breast cancer patients with high HER2 although the cardiotoxicity restricts its clinical usage. DNA damage and ferroptosis are implicated in anti-tumor drug cardiotoxicity. Given the emerging use of SGLT2 inhibitors in clinical cardiology, this study evaluated the impact of SGLT2 inhibitor Empagliflozin on TZM-induced cardiotoxicity, and mechanism involved with a focus on DNA damage and ferroptosis. Adult C57BL/6 mice were challenged with TZM (10 mg/kg/week, i.p.) or saline for six weeks. A cohort of mice received Empagliflozin (10 mg/kg, i.p.) at the same time. Myocardial function, morphology, ultrastructure, mitochondrial integrity, oxidative stress, DNA damage and various cell death domains were evaluated in TZM-challenged mice with or without Empagliflozin treatment. Our data revealed that TZM challenge overtly increased levels of serum LDH and troponin I, promoted adverse myocardial remodeling (increased heart weight, chamber size, cardiomyocyte area and interstitial fibrosis), contractile dysfunction and intracellular Ca2+ mishandling, oxidative stress, lipid peroxidation, mitochondrial ultrastructural damage, DNA damage, apoptosis and ferroptosis, the effects of which were greatly attenuated or mitigated by Empagliflozin with little effects from Empagliflozin itself. In vitro study indicated that induction of DNA damage mimicked TZM-induced lipid peroxidation and cardiomyocyte contractile dysfunction while the ferroptosis inducer erastin mitigated Empagliflozin-offered protection against lipid peroxidation and cardiomyocyte dysfunction (but not DNA damage). Likewise, in vivo and in vitro inhibition of ferroptosis recapitulated Empagliflozin-offered cardioprotection against TZM exposure. Taken together, these data demonstrated that Empagliflozin may be possible candidate drug for TZM cardiotoxicity likely through a DNA damage-ferroptosis-mediated mechanism.


Assuntos
Ferroptose , Inibidores do Transportador 2 de Sódio-Glicose , Camundongos , Animais , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Trastuzumab/farmacologia , Camundongos Endogâmicos C57BL , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Dano ao DNA
10.
Materials (Basel) ; 15(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36431695

RESUMO

The interfacial properties between the asphalt mastic and fibers plays an essential role in the fiber-enhanced asphalt mixture properties. However, there is a lack of comprehensive studies on the indicators to evaluate the interfacial interaction ability of fibers with the asphalt mastic. Therefore, this paper selected three types of basalt fibers (denoted as A-BF, B-BF and C-BF) coated with different impregnating agents to prepare the fiber asphalt mastic. The Dynamic Shear Rheometer (DSR) test-based indicators, pull-out strength, and adhesion work were used to access the fiber asphalt mastic interfacial interaction ability. The differences between different indicators were compared and analyzed. The results show that all the selected indicators in this paper can effectively reflect the different fiber asphalt mastic interfacial properties. The evaluation results with different indicators are consistent. The interfacial interaction between fibers and the asphalt mastic increases with increasing temperature. The evaluation result with adhesion work is the most accurate. However, the pull-out strength test is simple, and the test result correlates well with adhesion work, which can be adopted daily to evaluate the fiber asphalt mastic interfacial properties.

11.
Biochim Biophys Acta Mol Basis Dis ; 1868(7): 166402, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35346820

RESUMO

Advanced aging exhibits altered cardiac geometry and function involving mitochondrial anomaly. Natural compounds display promises in the regulation of cardiac homeostasis via governance of mitochondrial integrity in aging. This study examined the effect of oleanolic acid (OA), a natural pentacyclic triterpenoid with free radical scavenging and P450 cyclooxygenase-regulating properties, on cardiac aging and mechanisms involved with a focus on mitophagy. Young (4-5 month-old) and old (22-24 month-old) mice were treated with OA for 6 weeks prior to assessment of cardiac function, morphology, ultrastructure, mitochondrial integrity, cell death and autophagy. Our data revealed that OA treatment alleviated aging-induced changes in myocardial remodeling (increased heart weight, chamber size, cardiomyocyte area and interstitial fibrosis), contractile function and intracellular Ca2+ handling, apoptosis, necroptosis, inflammation, autophagy and mitophagy (LC3B, p62, TOM20 and FUNDC1 but not BNIP3 and Parkin). OA treatment rescued aging-induced anomalies in mitochondrial ultrastructure (loss of myofilament alignment, swollen mitochondria, increased circularity), mitochondrial biogenesis and O2- production without any notable effect at young age. Interestingly, OA-offered benefit against cardiomyocyte aging was nullified by deletion of the mitophagy receptor FUNDC1 using FUNDC1 knockout mice, denoting an obligatory role for FUNDC1 in OA-elicited preservation of mitophagy. OA reconciled aging-induced changes in E3 ligase MARCH5 but not FBXL2, and failed to affect aging-induced rises in IP3R3. Taken together, our data indicated a beneficial role for OA in attenuating cardiac remodeling and contractile dysfunction in aging through a FUNDC1-mediated mechanism.


Assuntos
Ácido Oleanólico , Triterpenos , Envelhecimento , Animais , Proteínas de Membrana/metabolismo , Camundongos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/fisiologia , Miócitos Cardíacos/metabolismo , Ácido Oleanólico/metabolismo , Ácido Oleanólico/farmacologia , Triterpenos/farmacologia
12.
Biochim Biophys Acta Gen Subj ; 1866(12): 130245, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36126834

RESUMO

BACKGROUND: Binge drinking leads to compromised mitochondrial integrity and contractile function in the heart although little effective remedy is readily available. Given the possible derangement of autophagy in ethanol-induced cardiac anomalies, this study was designed to examine involvement of Beclin1 in acute ethanol-induced cardiac contractile dysfunction, in any, and the impact of Beclin1 haploinsufficiency on ethanol cardiotoxicity with a focus on autophagy-related ferroptosis. METHODS: WT and Beclin1 haploinsufficiency (BECN+/-) mice were challenged with ethanol for one week (2 g/kg, i.p. on day 1, 3 and 7) prior to assessment of cardiac injury markers (LDH, CK-MB), cardiac geometry, contractile and mitochondrial integrity, oxidative stress, lipid peroxidation, apoptosis and ferroptosis. RESULTS: Ethanol exposure compromised cardiac geometry and contractile function accompanied with upregulated Beclin1 and autophagy, mitochondrial injury, oxidative stress, lipid peroxidation and apoptosis, and ferroptosis (GPx4, SLC7A11, NCOA4). Although Beclin1 deficiency did not affect cardiac function in the absence of ethanol challenge, it alleviated ethanol-induced changes in cardiac injury biomarkers, cardiomyocyte area, interstitial fibrosis, echocardiographic and cardiomyocyte mechanical properties along with mitochondrial integrity, oxidative stress, lipid peroxidation, apoptosis and ferroptosis. Ethanol challenge evoked pronounced ferroptosis (downregulated GPx4, SLC7A11 and elevated NCOA4, lipid peroxidation), the effect was alleviated by Beclin1 haploinsufficiency. Inhibition of ferroptosis using LIP-1 rescued ethanol-induced cardiac mechanical anomalies. In vitro study noted that ferroptosis induction using erastin abrogated Beclin1 haploinsufficiency-induced response against ethanol. CONCLUSIONS: In sum, our data suggest that Beclin1 haploinsufficiency benefits acute ethanol challenge-induced myocardial remodeling and contractile dysfunction through ferroptosis-mediated manner.


Assuntos
Ferroptose , Cardiopatias , Camundongos , Animais , Proteína Beclina-1/genética , Proteína Beclina-1/farmacologia , Miócitos Cardíacos , Etanol/toxicidade
13.
Arch Biochem Biophys ; 511(1-2): 1-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21530483

RESUMO

Activation of adenosine monophosphate-activated protein kinase (AMPK) has been shown to inhibit cardiac hypertrophy through peroxisome proliferators-activated receptor-α (PPARα) signaling pathway, but the detailed mechanism remains unclear. A rat model of cardiac hypertrophy created by transaortic constriction (TAC) was used to investigate the mechanism involved in regulation of PPARα activity by AMPK. It was observed that treatment with AICAR (5-aminoimidazole 1 carboxamide ribonucleoside), an AMPK activator, significantly inhibited cardiac hypertrophy in vivo and in vitro. Phosphorylated extracellular signal regulated protein kinase (phospho-ERK1/2) and phospho-p38 mitogen-activated protein kinase (MAPK) protein levels were significantly up-regulated, while PPARα protein level was down-regulated in TAC rats. AICAR treatment reversed the changes of PPARα and phospho-ERK1/2, but increased phospho-p38 MAPK protein level in TAC rats. Similar changes of PPARα and phospho-ERK1/2 protein levels were observed in the hypertrophied cardiomyocytes induced by phenylephrine treatment. Epidermal growth factor (EGF, ERK1/2 activator), but not SB203580 (p38 inhibitor) blocked the up-regulation of PPARα protein level induced by AICAR. Luciferase assay showed that AICAR increased PPARα transcriptional activity which was abrogated by EGF, but not by SB203580. These results demonstrate that AMPK activation enhances the activity of PPARα to inhibit cardiac hypertrophy through ERK1/2, but not p38 MAPK, signaling pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/prevenção & controle , Sistema de Sinalização das MAP Quinases , PPAR alfa/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Cardiomegalia/etiologia , Cardiomegalia/patologia , Células Cultivadas , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Ribonucleotídeos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Materials (Basel) ; 14(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34640105

RESUMO

A wide variety of polymer additives have been widely used in recent years. However, the effect of different polymer additives on the durability of asphalt binders has not been investigated thoroughly. To evaluate the aging property of styrene-butadiene-styrene (SBS) asphalt binder with different polymer additives, three polymer modifiers, namely high modulus modifier (HMM), anti-rutting agent (ARA), and high viscosity modifier (HVM), were added to it. First, the Thin Film Over Test (TFOT) and Pressure Aging Vessel (PAV) was performed on the asphalt binders. The rheological properties of the four asphalt binders before and after aging were then checked by the Dynamic Shear Rheometer Test (DSR). The chemical compositions of the asphalt binders were determined by the Fourier Transform Infrared Spectrometer (FTIR) test. Several aging indicators were adopted to reflect the aging degree of the asphalt binders. The results show that when polymer additives are added to the SBS asphalt binder, the complex modulus, storage modulus, loss modulus, and rutting factor substantially increase and the phase angle decreases. All the test parameters become higher after aging. The phase angle of the SBS asphalt binder is the highest at both unaged and aged states, while its other parameters values are the smallest. Moreover, the Carbonyl Aging Indicator (CAI) of SBS with polymer additives becomes lower under both TFOT and PAV conditions, indicating that polymer additives can improve the aging resistance of SBS asphalt, of which HVM modifies the aging resistance best. Complex Modulus Aging Indicator (CMAI) and Storage Modulus Aging Indicator (SMAI) have the best correlation coefficients with CAI, and the two aging indicators can be used to predict the aging degree of polymer modified asphalt binders.

15.
Materials (Basel) ; 14(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34885581

RESUMO

It is now more popular to use basalt fibers in the engineering programs to reinforce the crack resistance of asphalt mixtures. However, research concerning the impact of the basalt fiber diameter on the macro performance of AC-13 mixtures is very limited. Therefore, in this paper, basalt fibers with three diameters, including 7, 13 and 25 µm, were selected to research the influences of fiber diameter on the crack resistance of asphalt mixtures. Different types of crack tests, such as the low temperature trabecular bending test (LTTB), the indirect tensile asphalt cracking test (IDEAL-CT), and the semi-circular bend test (SCB), were conducted to reveal the crack resistance of AC-13 mixtures. The entire cracking process was recorded through the digital image correlation (DIC) technique, and the displacement cloud pictures, strain, average crack propagation rate (V) and fracture toughness (FT) indicators were used to evaluate the crack inhibition action of the fiber diameter on the mixture. The results showed that the incorporation of basalt fiber substantially improved the crack resistance, slowed down the increase of the displacement, and delayed the fracture time. Basalt fiber with a diameter of 7 µm presented the best enhancement capability on the crack resistance of the AC-13 mixture. The flexibility index (FI) of the SCB test showed a good correlation with V and FT values of DIC test results, respectively. These findings provide theoretical advice for the popularization and engineering application of basalt fibers in asphalt pavement.

16.
Materials (Basel) ; 14(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204444

RESUMO

To evaluate the long-term performances of different polymer-modified asphalt mixtures, three modifiers were chosen to modify AC-13 (defined as the asphalt concrete with the aggregate nominal maximum particle size of 13.2 mm); namely, high viscosity modifier (HVM), high modulus modifier (HMM), and anti-rutting agent (ARA). The deformation and cracking resistance of different polymer-modified mixtures were checked at different aging conditions (unaged, short-term aged, and long-term aged for 5, 10, and 15 days respectively). The results of the Hamburg wheel-track test and uniaxial penetration test (UPT) showed that the rutting resistance of all asphalt mixtures changed in a V-shape as the aging progressed. From the unaged stage to the long-term aging stage (5 days), the rutting resistance decreases gradually. While after the long-term aging stage (5 days), the rutting resistance increases gradually. Results from the semicircular bending test (SCB) and the indirect tensile asphalt cracking test (IDEAL-CT) indicated that the cracking resistance of all the mixtures gradually decline with the deepening of the aging degree, indicating that aging weakens the crack resistance of asphalt mixtures. Additionally, test results showed that the rutting resistance of ARA AC-13 (defined as AC-13 containing ARA) is the best, the cracking resistances of ARA AC-13, HMM AC-13 (defined as AC-13 containing HMM) and HVM AC-13 (defined as AC-13 containing HVM) have no significant difference, and different polymer modifiers had different sensitivities to aging due to the polymer content and the type of modifier. The conclusions of this study help to further understand the long-term performance of polymer-modified asphalt mixtures during service life and to help guide the selection of modifiers for mixtures.

17.
Vasc Health Risk Manag ; 17: 571-580, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552329

RESUMO

INTRODUCTION: The lipid-modifying potential of omega-3 polyunsaturated fatty acids in Chinese patients is under-researched. We conducted a multicenter, randomized, placebo-controlled, double-blind, parallel-group study of twice-daily treatment with OMACOR (OM3EE), a prescription-only formulation of highly purified ethyl esters of omega-3 polyunsaturated fatty acids in Chinese adult patients (≥18 years) who had elevated baseline fasting serum triglycerides (TG). METHODS: Patients were stratified according to the severity of their hypertriglyceridemia (severe HTG, with baseline TG ≥500 and <1000 mg/dL or moderate HTG, with baseline TG >200 and <500 mg/dL) or use of statins. Patients randomized to OM3EE therapy received 2 g/day for 4 weeks, then 4 g/day for 8 weeks. The primary efficacy endpoint was the percentage change in fasting serum TG between baseline and the end of treatment in patients with severe HTG. The study was concluded after a planned interim analysis demonstrated a significant TG-lowering effect of OM3EE in that contingent (p=0.0019). RESULTS: The mean TG end-of-treatment effect of OM3EE was -29.46% (standard deviation 40.60%) in the severe HTG contingent compared with +0.26% (standard deviation 54.68%) in the placebo group. Corresponding changes were -12.12% and -23.25% in the moderate HTG and combination cohorts (vs +55.45% and +6.24% in relevant placebo groups). A dose-dependent reduction in TG was evident in all patient contingents. Safety and tolerability of OM3EE were in line with previous experience. DISCUSSION: These data indicate that OMACOR therapy at a dose of 2-4 g/day is an effective treatment for Chinese patients with raised TG levels and is well tolerated.


Assuntos
Ácido Eicosapentaenoico/uso terapêutico , Ácidos Graxos Ômega-3/uso terapêutico , Hipertrigliceridemia/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Adulto , China , Método Duplo-Cego , Ácido Eicosapentaenoico/efeitos adversos , Etil-Éteres , Ácidos Graxos Ômega-3/efeitos adversos , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/complicações , Hipertrigliceridemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Triglicerídeos/sangue
18.
Metabolism ; 122: 154840, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331963

RESUMO

OBJECTIVE: Ferroptosis is indicated in cardiovascular diseases. Given the prominent role of mitophagy in the governance of ferroptosis and our recent finding for FUN14 domain containing 1 (FUNDC1) in obesity anomalies, this study evaluated the impact of FUNDC1 deficiency in high fat diet (HFD)-induced cardiac anomalies. METHODS AND MATERIALS: WT and FUNDC1-/- mice were fed HFD (45% calorie from fat) or low fat diet (LFD, 10% calorie from fat) for 10 weeks in the presence of the ferroptosis inhibitor liproxstatin-1 (LIP-1, 10 mg/kg, i.p.). RESULTS: RNAseq analysis for differentially expressed genes (DEGs) reported gene ontology term related to ferroptosis and mitophagy in obese rat hearts, which was validated in obese rodent and human hearts. Although 10-week HFD intake did not alter global metabolism, cardiac geometry and function, ablation of FUNDC1 unmasked metabolic derangement, pronounced cardiac remodeling, contractile, intracellular Ca2+ and mitochondrial anomalies upon HFD challenge, the effects of which with exception of global metabolism were attenuated or mitigated by LIP-1. FUNDC1 ablation unmasked HFD-evoked rises in fatty acid synthase ACSL4, necroptosis, inflammation, ferroptosis, mitochondrial O2- production, and mitochondrial injury as well as dampened autophagy and DNA repair enzyme 8-oxoG DNA glycosylase 1 (OGG1) but not apoptosis, the effect of which except ACSL4 and its regulator SP1 was reversed by LIP-1. In vitro data noted that arachidonic acid, an ACSL4 substrate, provoked cytochrome C release, cardiomyocyte defect, and lipid peroxidation under FUNDC1 deficiency, the effects were interrupted by inhibitors of SP1, ACSL4 and ferroptosis. CONCLUSIONS: These data suggest that FUNDC1 deficiency sensitized cardiac remodeling and dysfunction with short-term HFD exposure, likely through ACSL4-mediated regulation of ferroptosis.


Assuntos
Coenzima A Ligases/metabolismo , Ferroptose/fisiologia , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Remodelação Ventricular/fisiologia , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Cálcio/metabolismo , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Mitofagia/fisiologia , Miócitos Cardíacos/metabolismo , Obesidade/metabolismo
19.
Biochim Biophys Acta Mol Basis Dis ; 1866(10): 165855, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512189

RESUMO

High fat diet intake contributes to undesired cardiac geometric and functional changes although the underlying mechanism remains elusive. Akt and AMPK govern to cardiac homeostasis. This study examined the impact of deletion of Akt2 (main cardiac isoform of Akt) and AMPKα2 on high fat diet intake-induced cardiac remodeling and contractile anomalies and mechanisms involved. Cardiac geometry, contractile, and intracellular Ca2+ properties were evaluated using echocardiography, IonOptix® edge-detection and fura-2 techniques in wild-type (WT) and Akt2-AMPK double knockout (DKO) mice receiving low fat (LF) or high fat (HF) diet for 4 months. Our results revealed that fat diet intake elicit obesity, cardiac remodeling (hypertrophy, LV mass, LVESD, and cross-sectional area), contractile dysfunction (fractional shortening, peak shortening, maximal velocity of shortening/relengthening, time-to-90% relengthening, and intracellular Ca2+ handling), ultrastructural disarray, apoptosis, O2-, inflammation, dampened autophagy and mitophagy. Although DKO did not affect these parameters, it accentuated high fat diet-induced cardiac remodeling and contractile anomalies. High fat intake upregulated levels of cyclic GMP-AMP synthase (cGAS), stimulator of interferon genes (STING), and STING phosphorylation while suppressing phosphorylation of ULK1 (Ser757 and Ser777), with a more pronounced effect in DKO mice. In vitro data revealed that inhibition of cGAS and STING using PF-06928215 and Astin C negated palmitic acid-induced cardiomyocyte contractile dysfunction. Biological function analysis for all differentially expressed genes (DEGs) depicted that gene ontology terms associated with Akt and AMPK signaling processes were notably changed in high fat-fed hearts. Our data indicate that Akt2-AMPK ablation accentuated high fat diet-induced cardiac anomalies possibly through a cGAS-STING-mechanism.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Hipertrofia Ventricular Esquerda/imunologia , Miocárdio/patologia , Obesidade/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Autofagia/genética , Autofagia/imunologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Mitofagia/genética , Mitofagia/imunologia , Miocárdio/citologia , Miocárdio/imunologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/patologia , Nucleotidiltransferases/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Remodelação Ventricular/genética
20.
Br J Pharmacol ; 177(8): 1881-1897, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31877229

RESUMO

BACKGROUND AND PURPOSE: Lipopolysaccharides (LPS), an outer membrane component of Gram-negative bacteria, triggers myocardial anomalies in sepsis. Recent findings indicated a role for inflammatory cytokine MIF and its receptor, CD74, in septic organ injury, although little is known of the role of MIF-CD74 in septic cardiomyopathy. EXPERIMENTAL APPROACH: This study evaluated the impact of CD74 ablation on endotoxaemia-induced cardiac anomalies. Echocardiographic, cardiomyocyte contractile and intracellular Ca2+ properties were examined. KEY RESULTS: Our data revealed compromised cardiac function (lower fractional shortening, enlarged LV end systolic diameter, decreased peak shortening, maximal velocity of shortening/relengthening, prolonged duration of relengthening and intracellular Ca2+ mishandling) and ultrastructural derangement associated with inflammation, O2 - production, apoptosis, excess autophagy, phosphorylation of AMPK and JNK and dampened mTOR phosphorylation. These effects were attenuated or mitigated by CD74 knockout. LPS challenge also down-regulated Skp2, an F-box component of Skp1/Cullin/F-box protein-type ubiquitin ligase, while up-regulating that of SUV39H1 and H3K9 methylation of the Bcl2 protein BCLB. These effects were reversed by CD74 ablation. In vitro study revealed that LPS facilitated GFP-LC3B formation and cardiomyocyte defects. These effects were prevented by CD74 ablation. Interestingly, the AMPK activator AICAR, the autophagy inducer rapamycin and the demethylation inhibitor difenoconazole inhibited the effects of CD74 ablation against LPS-induced cardiac dysfunction, while the SUV39H1 inhibitor chaetocin or methylation inhibitor 5-AzaC ameliorated LPS-induced GFP-LC3B formation and cardiomyocyte contractile dysfunction. CONCLUSION AND IMPLICATIONS: Our data suggested that CD74 ablation protected against LPS-induced cardiac anomalies, O2 - production, inflammation and apoptosis through suppression of autophagy in a Skp2-SUV39H1-mediated mechanism.


Assuntos
Antígenos de Diferenciação de Linfócitos B/genética , Cardiomiopatias , Antígenos de Histocompatibilidade Classe II/genética , Contração Miocárdica , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Autofagia , Cálcio/metabolismo , Cardiomiopatias/metabolismo , Desmetilação , Lipopolissacarídeos , Metiltransferases/metabolismo , Camundongos Knockout , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Quinases , Proteínas Repressoras/metabolismo , Proteínas Quinases Associadas a Fase S
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