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BACKGROUND: There is an urgent need to develop an efficient therapeutic strategy for heart failure with preserved ejection fraction (HFpEF), which is mediated by phenotypic changes in cardiac macrophages. We previously reported that vitamin B-6 inhibits macrophage-mediated inflammasome activation. OBJECTIVES: We sought to examine whether the prophylactic use of vitamin B-6 prevents HFpEF. METHODS: HFpEF model was elicited by a combination of high-fat diet and Nω-nitro-l-arginine methyl ester supplement in mice. Cardiac function was assessed using conventional echocardiography and Doppler imaging. Immunohistochemistry and immunoblotting were used to detect changes in the macrophage phenotype and myocardial remodeling-related molecules. RESULTS: Co-administration of vitamin B-6 with HFpEF mice mitigated HFpEF phenotypes, including diastolic dysfunction, cardiac macrophage phenotypic shifts, fibrosis, and hypertrophy. Echocardiographic improvements were observed, with the E/E' ratio decreasing from 42.0 to 21.6 and the E/A ratio improving from 2.13 to 1.17. The exercise capacity also increased from 295.3 to 657.7 min. However, these beneficial effects were negated in downstream of kinase (DOK) 3-deficient mice. Mechanistically, vitamin B-6 increased DOK3 protein concentrations and inhibited macrophage phenotypic changes, which were abrogated by an AMP-activated protein kinase inhibitor. CONCLUSIONS: Vitamin B-6 increases DOK3 signaling to lower risk of HFpEF by inhibiting phenotypic changes in cardiac macrophages.
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Imbalance of proinflammatory and anti-inflammatory responses plays a crucial role in the progression of abdominal aortic aneurysms. ILF3, a known modulator of the innate immune response, is involved in cardiovascular diseases. This study aims to investigate the role of ILF3 in abdominal aortic aneurysm formation. Here, we use multi-omics analyzes, transgenic male mice, and multiplex immunohistochemistry to unravel the underlying involvement of ILF3 in abdominal aortic aneurysms. The results show that macrophage ILF3 deficiency attenuates abdominal aortic aneurysm progression, while elevated macrophage ILF3 exacerbates abdominal aortic aneurysm lesions. Mechanistically, we reveal that macrophagic ILF3 increases NF-κB activity by hastening the decay of p105 mRNA, leading to amplified inflammation in macrophages. Meanwhile, ILF3 represses the anti-inflammatory action by inhibiting the Keap1-Nrf2 signaling pathway through facilitating the ILF3/eIF4A1 complex-mediated enhancement of Keap1 translational efficiency. Moreover, Bardoxolone Methyl treatment alleviates the severity of abdominal aortic aneurysm lesions in the context of elevated ILF3 expression. Together, our findings underscore the significance of macrophage ILF3 in abdominal aortic aneurysm development and suggest its potential as a promising therapeutic target for abdominal aortic aneurysms.
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Aneurisma da Aorta Abdominal , Inflamação , Macrófagos , Proteínas do Fator Nuclear 90 , Transdução de Sinais , Animais , Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/genética , Masculino , Macrófagos/metabolismo , Macrófagos/imunologia , Camundongos , Proteínas do Fator Nuclear 90/metabolismo , Proteínas do Fator Nuclear 90/genética , Inflamação/metabolismo , Inflamação/patologia , NF-kappa B/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais de Doenças , Camundongos KnockoutRESUMO
Cardiac fibrosis is a typical feature of cardiac pathological remodeling, which is associated with adverse clinical outcomes and has no effective therapy. Nicotine is an important risk factor for cardiac fibrosis, yet its underlying molecular mechanism remains poorly understood. This study aimed to identify its potential molecular mechanism in nicotine-induced cardiac fibrosis. Our results showed nicotine exposure led to the proliferation and transformation of cardiac fibroblasts (CFs) into myofibroblasts (MFs) by impairing autophagy flux. Through the use of drug affinity responsive target stability (DARTS) assay, cellular thermal shift assay (CETSA), and surface plasmon resonance (SPR) technology, it was discovered that nicotine directly increased the stability and protein levels of lactate dehydrogenase A (LDHA) by binding to it. Nicotine treatment impaired autophagy flux by regulating the AMPK/mTOR signaling pathway, impeding the nuclear translocation of transcription factor EB (TFEB), and reducing the activity of cathepsin B (CTSB). In vivo, nicotine treatment exacerbated cardiac fibrosis induced in spontaneously hypertensive rats (SHR) and worsened cardiac function. Interestingly, the absence of LDHA reversed these effects both in vitro and in vivo. Our study identified LDHA as a novel nicotine-binding protein that plays a crucial role in mediating cardiac fibrosis by blocking autophagy flux. The findings suggest that LDHA could potentially serve as a promising target for the treatment of cardiac fibrosis.
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Autofagia , Fibrose , Nicotina , Animais , Autofagia/efeitos dos fármacos , Ratos , Masculino , Ratos Endogâmicos SHR , Transdução de Sinais/efeitos dos fármacos , Miocárdio/patologia , Miocárdio/metabolismo , Lactato Desidrogenase 5/metabolismo , Células Cultivadas , Humanos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Ratos Sprague-DawleyRESUMO
Heart failure with preserved ejection fraction (HFpEF) is associated with endothelial dysfunction. We have previously reported that statins prevent endothelial dysfunction through inhibition of microRNA-133a (miR-133a). This study is to investigate the effects and the underlying mechanisms of statins on HFpEF. Here, we show that statins upregulate the expression of a circular RNA (circRNA-RBCK1) which is co-transcripted with the ring-B-box-coiled-coil protein interacting with protein kinase C-1 (RBCK1) gene. Simultaneously, statins increase activator protein 2 alpha (AP-2α) transcriptional activity and the interaction between circRNA-RBCK1 and miR-133a. Furthermore, AP-2α directly interacts with RBCK1 gene promoter in endothelial cells. In vivo, lovastatin improves diastolic function in male mice under HFpEF, which is abolished by loss function of endothelial AP-2α or circRNA-RBCK1. This study suggests that statins upregulate the AP-2α/circRNA-RBCK1 signaling to suppress miR-133a in cardiac endothelial cells and prevent diastolic dysfunction in HFpEF.
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Insuficiência Cardíaca , Inibidores de Hidroximetilglutaril-CoA Redutases , MicroRNAs , Animais , Masculino , Camundongos , Células Endoteliais/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , MicroRNAs/metabolismo , RNA Circular/genética , Volume Sistólico/fisiologiaRESUMO
BACKGROUND: The pathogenesis of vascular dementia (VD) is complex, and currently, no effective treatments have been recommended. Floralozone is a colorless liquid first discovered in Lagotis Gaertn. Recently, its medicinal value has been increasingly recognized. Our previous study has demonstrated that Floralozone can improve cognitive dysfunction in rats with VD by regulating the transient receptor potential melastatin 2 (TRPM2) and N-methyl-D-aspartate receptor (NMDAR) signaling pathways. However, the mechanism by which Floralozone regulates TRPM2 and NMDAR to improve VD remains unclear. AMP-activated protein kinase (AMPK) is an energy regulator in vivo; however, its role of AMPK activation in stroke remains controversial. MiR-7a-5p has been identified to be closely related to neuronal function. PURPOSE: To explore whether Floralozone can regulate the miR-7a-5p level in vivo through AMPKα2 activation, affect the TRPM2 and NR2B expression levels, and improve VD symptoms. METHODS: The VD model was established by a modified bilateral occlusion of the common carotid arteries (2-VO) of Sprague-Dawley (SD) rats and AMPKα2 KO transgenic (AMPKα2-/-) mice. Primary hippocampal neurons were modeled using oxygen and glucose deprivation (OGD). Morris water maze (MWM) test, hematoxylin-eosin staining (HE staining), and TUNEL staining were used to investigate the effects of Floralozone on behavior and hippocampal morphology in rats. Minichromosome maintenance complex component 2(MCM2) positive cells were used to investigate the effect of Floralozone on neurogenesis. Immunofluorescence staining, qRT-PCR, and western blot analysis were used to investigate the effect of Floralozone on the expression levels of AMPKα2, miR-7a-5p, TRPM2, and NR2B. RESULTS: The SD rat experiment revealed that Floralozone improved spatial learning and memory, improved the morphology and structure of hippocampal neurons, reduced apoptosis of hippocampal neurons and promoted neurogenesis in VD rats. Floralozone could increase the miR-7a-5p expression level, activate AMPKα2 and NR2B expressions, and inhibit TRPM2 expression in hippocampal neurons of VD rats. The AMPKα2 KO transgenic (AMPKα2-/-) mice experiment demonstrated that Floralozone could regulate miR-7a-5p, TRPM2, and NR2B expression levels through AMPKα2 activation. The cell experiment revealed that the TRPM2 and NR2B expression levels were regulated by miR-7a-5p, whereas the AMPKα2 expression level was not. CONCLUSION: Floralozone could regulate miR-7a-5p expression level by activating the protein expression of AMPKα2, control the protein expression of TRPM2 and NR2B, improve the morphology and structure of hippocampus neurons, reduce the apoptosis of hippocampus neurons, promote neurogenesis and improve the cognitive dysfunction.
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Proteínas Quinases Ativadas por AMP , Disfunção Cognitiva , Demência Vascular , MicroRNAs , Animais , Masculino , Camundongos , Ratos , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/genética , Demência Vascular/genética , Demência Vascular/tratamento farmacológico , Demência Vascular/metabolismo , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , MicroRNAs/genética , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Ratos Sprague-Dawley , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismoRESUMO
Vascular dementia (VD) is one of the most common causes of dementia, taking account for about 20% of all cases. Although studies have found that selenium supplementation can improve the cognitive ability of Alzheimer's patients, there is currently no research on the cognitive impairment caused by VD. This study aimed to investigate the role and mechanism of Amorphous selenium nanodots (A SeNDs) in the prevention of VD. The bilateral common carotid artery occlusion (BCCAO) method was used to establish a VD model. The neuroprotective effect of A SeNDs was evaluated by Morris water maze, Transcranial Doppler TCD, hematoxylin-eosin (HE) staining, Neuron-specific nuclear protein (Neu N) staining and Golgi staining. Detect the expression levels of oxidative stress and Calcium-calmodulin dependent protein kinase II (CaMK II), N-methyl-D-aspartate receptor subunit NR2A, and postsynaptic dense protein 95 (PSD95). Finally, measure the concentration of calcium ions in neuronal cells. The results showed that A SeNDs could significantly improve the learning and memory ability of VD rats, restore the posterior arterial blood flow of the brain, improve the neuronal morphology and dendritic remodeling of pyramidal cells in hippocampal CA1 area, reduce the level of oxidative stress in VD rats, increase the expression of NR2A, PSD95, CaMK II proteins and reduce intracellular calcium ion concentration, but the addition of selective NR2A antagonist NVP-AAMO77 eliminated these benefits. It suggests that A SeNDs may improve cognitive dysfunction in vascular dementia rats by regulating the NMDAR pathway.
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Demência Vascular , Selênio , Ratos , Animais , Demência Vascular/tratamento farmacológico , Demência Vascular/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Cálcio/metabolismo , Estresse Oxidativo , Hipocampo , Neurônios/metabolismo , Aprendizagem em LabirintoRESUMO
Diabetic cardiomyopathy (DCM) is part of the most important causes of death from cardiovascular disease. Perillaldehyde (PAE), a major component of the herb perilla, has been shown to ameliorate doxorubicin-induced cardiotoxicity, but it is unclear whether PAE exerts beneficial effects on DCM. Exploring the potential molecular mechanisms of PAE for the treatment of DCM through network pharmacology and molecular docking. The SD rat type 1 diabetes model was established by a single intraperitoneal injection of streptozotocin (60 mg/kg), the cardiac function indexes of each group were detected by echocardiography; the morphological changes, apoptosis, protein expression of P-GSK-3ß (S9), collagen I (Col-â ), collagen III (Col-â ¢) and alpha-smooth muscle actin (α-SMA), and miR-133a-3p expression levels were detected. An DCM model of H9c2 cells was established in vitro and transfected with Mimic and Inhibitor of miR-133a-3p. The results showed that PAE ameliorated cardiac dysfunction, reduced fasting glucose and cardiac weight index, and improved myocardial injury and apoptosis in DCM rats. It reduced high glucose-induced apoptosis, promoted migration and improved mitochondrial division injury in H9c2 cells. PAE decreased P-GSK-3ß (S9), Col-â , Col-â ¢ and α-SMA protein expression and upregulated miR-133a-3p expression levels. After miR-133a-3p Inhibitor treatment, the expression of P-GSK-3ß (S9) and α-SMA expression were significantly increased; after miR-133a-3p Mimic treatment, the expression of P-GSK-3ß (S9) and α-SMA decreased significantly in H9c2 cells. It suggests that the mechanism of action of PAE to improve DCM may be related to the upregulation of miR-133a-3p and inhibition of P-GSK-3ß expression.
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Diabetes Mellitus , Cardiomiopatias Diabéticas , MicroRNAs , Ratos , Animais , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Transdução de Sinais , Simulação de Acoplamento Molecular , Ratos Sprague-Dawley , Apoptose , Colágeno/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Glucose/farmacologiaRESUMO
Vascular smooth muscle cells (VSMCs) constitute the medial layer of the blood vessel wall. Their contractile state regulates blood flow in physiological and pathological conditions. Current methods for assessing the contractility of VSMCs are not amenable to the high-throughput screening of pharmaceutical compounds. This study aimed to develop a method to address this shortcoming in the field. Real-time contraction was visualized in living VSMCs using the exogenous expression of green fluorescent protein (GFP). Image-Pro Plus software (IPPS) was used to measure various morphological cell indices. In phenylephrine-treated VSMCs, GFP fluorescence imaging was more accurate than brightfield imaging or phalloidin staining in representing VSMC morphology, as measured using IPPS. Among the multiple indices of VSMC shape, area and mean-diameter were more sensitive than length in reflecting the morphological changes in VSMC. We developed a new index, compound length, by combining the mean-diameter and length to differentiate contracted and uncontracted VSMCs. Based on the compound length, we further generated a contraction index to define a single-VSMC contractile status as single-VSMC contraction-index (SVCI). Finally, compound length and SVCI were validated to effectively assess cell contraction in VSMCs challenged with U46619 and KCl. In conclusion, GFP-based indices of compound length and SVCI can accurately quantify the real-time contraction of VSMCs. In future, the new method will be applied to high-throughput drug screening or basic cardiovascular research.
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Músculo Liso Vascular , Miócitos de Músculo Liso , Músculo Liso Vascular/metabolismo , Fenilefrina/farmacologia , Fenilefrina/metabolismo , Miócitos de Músculo Liso/metabolismo , Células Cultivadas , Contração MuscularRESUMO
BACKGROUND: s: Hyperhomocysteinemia (HHcy) is one of risk factors for vascular cognitive impairment (VCI). GTP cyclohydrolase 1 (GCH1) deficiency is critical to oxidative stress in vascular dysfunction. The aim of this study was designed to examine whether HHcy induces VCI through GCH1 S-nitrosylation, a redox-related post-translational modification of cysteine. METHODS: The VCI model was induced by feeding mice homocysteine thiolactone (HTL) for 16 consecutive weeks. The cognitive functions were evaluated by step-down avoidance test, passive avoidance step-through task test, and Morris water maze (MWM) test. Protein S-nitrosylation was assayed using a biotin-switch method. RESULTS: In cell-free system, nitric oxide (NO) donor induced GCH1 protein S-nitrosylation and decreased GCH1 activity. In endothelial cells, HTL increased GCH1 S-nitrosylation, reduced tetrahydrobiopterin, and induced oxidative stress, which were attenuated by N-acetyl-cysteine, L-N6-1-Iminoethyl-lysine, mutant of GCH1 cysteine 141 to alanine (MT-GCH1) or gene deletion of inducible NO synthase (iNOS). Further, HTL incubation or iNOS overexpression promoted endothelial cellular senescence, but abolished by exogenous expression of MT-GCH1 or pharmacological approaches including N-acetyl-cysteine, L-sepiapterin, and tempol. In wildtype mice, long-term administration of HTL induced GCH1 S-nitrosylation and vascular stiffness, decreased cerebral blood flow, and damaged the cognitive functions. However, these abnormalities induced by HTL administration were rescued by enforced expression of MT-GCH1 or gene knockout of iNOS. In human subjects, GCH1 S-nitrosylation was increased and cognitive functions were impaired in patients with HHcy. CONCLUSION: The iNOS-mediated nitrosative stress induced by HTL drives GCH1 S-nitrosylation to induce cerebral vascular stiffness and cognitive impairments.
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Disfunção Cognitiva , Hiper-Homocisteinemia , Animais , Humanos , Camundongos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Cisteína/metabolismo , Células Endoteliais/metabolismo , GTP Cicloidrolase , Hiper-Homocisteinemia/induzido quimicamente , Hiper-Homocisteinemia/metabolismo , Óxido Nítrico/metabolismo , Estresse NitrosativoRESUMO
Objectives: Epigallocatechin-3-gallate (EGCG) has a good therapeutic effect on type 2 diabetes mellitus (T2DM). This work was designed to explore EGCG's effectiveness in insulin resistance (IR) and pancreas islet ß-cell function in a rat model of T2DM. Materials and Methods: Eight-week-old male Sprague Dawley rats were randomly divided into 6 groups, including the Control (normal diet), Diabetes (high-sucrose high-fat [HSHF] diet combined with tail vein injection of streptozotocin [STZ] for T2DM induction) and Treatment Diabetic rats which were treated with metformin [500 mg/kg/d] or EGCG [25, 50 or 100 mg/kg/d] intragastric administration for 10 weeks. With the exception of control animals, the other groups were fed the HSHF diet. EGCG's effects on IR and insulin secretion were assessed by measuring body weights, and fasting blood glucose (FBG), postprandial blood glucose (PBG) and insulin levels. The morphological and molecular changes of pancreas islet ß-cells were examined by hematoxylin-eosin (H&E) staining, transmission electron microscopy (TEM) and immunofluorescence. Results: Rats fed the HSHF diet combined with STZ treatment had increased body weights and blood glucose amounts, accompanied by IR and impaired ß-cell function, induced T2DM, and EGCG dose-dependently restored the above indicators. Additionally, EGCG upregulated the pancreatic transcription factors pancreatic duodenal homeobox protein-1 (PDX-1) and musculoaponeurotic fibrosarcoma oncogene homolog A (MafA). Conclusion: These results suggest that EGCG reduces blood glucose amounts, and improve IR and islet ß-cell disorder in T2DM.
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OBJECTIVES: This work aimed to determine tert-Butylhydroquinone (TBHQ)'s effects on insulin resistance (IR) and liver steatosis in diabetic animals and to explore the underpinning mechanisms. MATERIALS AND METHODS: Male ApoE-/-mice underwent streptozocin (STZ) administration while receiving a sucrose/fat-rich diet for type 2 diabetes mellitus (T2DM) establishment. This was followed by a 6-week TBHQ administration. Body weight, fasting (FBG) and postprandial (PBG) blood glucose amounts, and insulin concentrations were measured, and the oral glucose tolerance test (OGTT) was carried out. Hematoxylin and eosin (H and E) staining and immunoblot were carried out for assessing histology and protein amounts in the liver tissue samples. In addition, cultured HepG2 cells were administered HClO and insulin for IR induction, and immunoblot was carried out for protein evaluation. Finally, the cells were stained with the Hoechst dye for apoptosis evaluation. RESULTS: The model animals showed T2DM signs, and TBHQ decreased FBG, ameliorated glucose tolerance and reduced liver steatosis in these animals. In addition, TBHQ markedly upregulated AMPKα2, GLUT4 and GSK3 ß, as well as phosphorylated PI3K and AKT in the liver of mice with T2DM. In agreement, TBHQ decreased HClO-and insulin-related IR in cells and suppressed apoptosis through AMPKα2/PI3K/AKT signaling. CONCLUSIONS: TBHQ alleviates IR and liver steatosis in a mouse model of T2DM likely through AMPKα2/PI3K/AKT signaling.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Fígado Gorduroso , Resistência à Insulina , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Quinase 3 da Glicogênio Sintase/metabolismo , Hidroquinonas , Insulina , Fígado/metabolismo , Masculino , Camundongos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-aktRESUMO
Moderate autophagy can remove damaged proteins and organelles. In some inflammatory diseases, autophagy plays a protective role by inhibiting the NOD-like receptor family pyrin domain containing 3(NLRP3). (Pro)renin receptor (PRR, or ATP6AP2) is a critical component of the V-ATPase required for autophagy. It remains controversial about ATP6AP2 in the pathological process. The impact of ATP6AP2 on NLRP3 inflammasome and autophagic flux remains unknown under pressure overload stress. This research explores the potential link between ATP6AP2, autophagic flux, and NLRP3. There was upregulation of ATP6AP2 from 5-day post-TAC, and this expression remained at a high level until 8-weeks post-TAC in wild mice. Meanwhile, autophagic flux switched from early compensatory activation to blocking in the heart failure phase. NLRP3 activation can be seen at 8-week post-TAC. Adenovirus-mediated knockdown of ATP6AP2(shR-ATP6AP2) accelerated the progress of heart failure. After TAC was induced, shR-ATP6AP2 significantly deteriorated heart function and fibrosis compared with the shR-Scr group. Meanwhile, there was an elevated expression of NLRP3 and autophagic flux blockage. A transgenic mouse(Tg) with cardio-restricted ATP6AP2/(P)RR overexpression was constructed. Although high expression in cardiac tissue, there were no spontaneous functional abnormalities under the basal state. Cardiac function, fibrosis, hypertrophy remained identical to the control TAC group. However, SQSTM1/P62 was reduced, which indicated the relief of autophagic flux blockage. Further, Neonatal rat ventricular myocyte (NRVMs) transfected with shR-ATP6AP2 showed more susceptibility than sh-Scr NRVMs to phenylephrine-induced cell death. More reactive oxygen species (ROS) or mito-ROS accumulated in the shR-ATP6AP2 group when phenylephrine stimulation. Blocking NLRP3 activation in vivo partly rescued cardiac dysfunction and fibrosis. In conclusion, ATP6AP2 upregulation is a compensatory response to pressure overload. If not effectively compensated, it compromises autophagic flux, leads to dysfunctional mitochondria accumulation, further produces ROS to activate NLRP3, eventually accelerates heart failure.
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The medical usage of Doxorubicin (DOX) as a chemotherapeutic agent is restricted owing to its cardiotoxic properties. This study was designed to explore the effect and underlying mechanisms of Citronellal (CT) on DOX-related cardiotoxicity in rats. Rats were divided into six groups: control, DOX, CT, Lithium chloride (LiCl) (a Na+/H+exchanger-1 [NHE1] activator), DOX + CT, and DOX + CT + LiCl. To induce cardiotoxicity, a cumulative dose of 15 mg/kg DOX was intraperitoneally injected into rats. CT (150 mg/kg) and LiCl (1 mg/kg) were given daily by oral gavage for 6 weeks. CT improved cardiac functional parameters and attenuated the cardiac pathological changes induced by DOX. Further study indicated that CT administration regulated the levels of oxidative stress and apoptosis-related factors and in myocardial tissues, reducing cell per-oxidative damage and apoptosis. Besides this, CT attenuated DOX-induced NHE1 upregulation, and the preventive effects of CT against DOX-induced cardiotoxicity were abrogated by the concurrent administration of LiCl. These results demonstrate that CT could ameliorate DOX-induced cardiotoxicity by inhibiting the NHE1-mediated oxidative stress, apoptosis in rats.
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Monoterpenos Acíclicos/farmacologia , Aldeídos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/efeitos adversos , Cardiopatias/tratamento farmacológico , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Trocador 1 de Sódio-Hidrogênio/metabolismo , Animais , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Doxorrubicina/farmacologia , Cardiopatias/induzido quimicamente , Cardiopatias/metabolismo , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Vascular cognitive dysfunction in patients with vascular dementia (VD) is a kind of severe cognitive dysfunction syndrome caused by cerebrovascular diseases. At present, effective drugs to improve the cognitive function of VD patients still need to be explored. Transient Receptor Potential Melastatin 2 (TRPM2) channel is a nonspecific cation channel that plays a key role in the toxic death of neurons. Perillaldehyde (PAE) has the protective effect of epilepsy and insomnia and other central nervous system diseases. The aim of this study is to explore whether PAE improves cognitive function in VD rats and to investigate the potential mechanisms in vivo and vitro. METHODS: VD rats were induced by bilateral common carotid arteries occlusion (2-vessel occlusion [2VO]) and treated with PAE for 4 weeks. The neuroprotective effects of PAE was subsequently assessed by the Morris water maze, hematoxylin-eosin (HE) staining, Golgi staining, electron microscopy, Neuron-specific nuclear protein (Neu N) staining, and TdT-mediated dUTP nick end labeling (TUNEL) staining. After primary hippocampal neurons were isolated, cell viability was detected by MTT assay and intracellular Ca2+ concentration was detected by calcium imaging assay. The content of Nitriteoxide (NO), Malondialdehyde (MDA) and Superoxide dismutase (SOD) activity in serum of rats were observed by Enzyme Linked Immunosorbent Assay (ELISA). Immunohistochemistry, Western blot, and Confocal laser scanning were used to detect the expression levels of N-methyl-D-asprtate receptor-2B (NR2B) and TRPM2. RESULTS: The results showed that PAE can improve the number and activity of neurons, increase the length and number of dendrites in hippocampus, decrease the Vv value and PE value of neuronal nucleus and mitochondrial structure significantly, increase the s value and L value in nucleus structure, decrease the s value and L value in mitochondrial structure, and improve the learning and memory ability of rats significantly. And PAE can strengthen the ability of antioxidant stress confirmed by increasing the activity of SOD and reducing the production of MDA. The results of western blot, immunohistochemistry and immunofluorescence showed that PAE could reduce the level of TRPM2 and increase the expression of NR2B. CONCLUSIONS: Taken together, our findings provide evidence that the neuroprotective effects of PAE in VD rats maybe through TRPM2 inhibition and subsequent activation of NMDAR signaling pathway.
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Diabetic cardiomyopathy (DCM), a cardiovascular complication of patients with diabetes, is a special cardiomyopathy that is independent of coronary heart disease, hypertension, and valvular disease. Citronellal (CT) is a monoterpene compound generated by the secondary metabolism of plants. In this work, the therapeutic effect and mechanism of CT in DCM were investigated. Experimental diabetic rat models were constructed through a high-fat and high-carbohydrate diet combined with low-dosage streptozotocin (STZ) treatment. CT was intragastrically administered at the dosage of 150 mg/kg/day. The cardiac functions of the rats were evaluated via cardiac Doppler ultrasound. Changes in myocardial structure were analyzed through histopathology. Changes in the representative indices of oxidative stress, namely, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were detected on the basis of a biochemical test. Related protein levels were assayed via immunofluorescence and Western blot analyses. The DCM rats in the nontreatment group experienced diastolic and systolic dysfunctions, associated with myocardial hypertrophy, fibrosis, and cardiomyocyte apoptosis. Moreover, this condition was concurrent with metabolic disorders, the degradation of SOD activity in myocardial tissues, the increase in MDA content, the abnormal activation of sodium-hydrogen exchanger 1 (NHE1), and the aggravation of cell apoptosis (Bax levels were elevated, whereas Bcl-2 levels decreased). Myocardial hypertrophy, fibrosis, oxidative stress, and cell apoptosis were obviously inhibited after treatment with CT (150 mg/kg/day). The abnormal activation of NHE1 was recovered under the action of CT. Our study results showed that CT might play a protective role in the treatment of DCM by repressing the abnormal activation of NHE1.
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BACKGROUNDS: A major side effect of statin, a widely used drug to treat hyperlipidemia, is skeletal myopathy through cell apoptosis. The aim of this study is to investigate the roles of microRNA in statin-induced injury. METHODS: Apolipoprotein E knockout (ApoE-/-) mice were administered with simvastatin (20 mg/kg/day) for 8 weeks. Exercise capacity was evaluated by hanging grid test, forelimb grip strength, and running tolerance test. RESULTS: In cultured skeletal muscle cells, statin increased the levels of miR-1a but decreased the levels of mitogen-activated protein kinase kinase kinase 1 (MAP3K1) in a time or dose dependent manner. Both computational target-scan analysis and luciferase gene reporter assay indicated that MAP3K1 is the target gene of miR-1a. Statin induced cell apoptosis of skeletal muscle cells, but abolished by downregulating of miR-1a or upregulation of MAP3K1. Further, the effects of miR-1a inhibition on statin-induced cell apoptosis were ablated by MAP3K1 siRNA. In ApoE-/- mice, statin induced cell apoptosis of skeletal muscle cells and decreased exercise capacity in mice infected with vector, but not in mice with lentivirus-mediated miR-1a gene silence. CONCLUSION: Statin causes skeletal injury through induction of miR-1a excessive expression to decrease MAP3K1 gene expression.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , MAP Quinase Quinase Quinase 1/genética , MicroRNAs/metabolismo , Fibras Musculares Esqueléticas/patologia , Doenças Musculares/induzido quimicamente , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Células Cultivadas , Modelos Animais de Doenças , Humanos , Hiperlipidemias/tratamento farmacológico , Camundongos , Camundongos Knockout para ApoE , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , Fibras Musculares Esqueléticas/efeitos dos fármacos , Doenças Musculares/diagnóstico , Doenças Musculares/genética , Doenças Musculares/patologia , Condicionamento Físico Animal , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Sinvastatina/efeitos adversos , Regulação para Cima/efeitos dos fármacosRESUMO
The effects of long-term nitrate therapy are compromised due to protein S-Nitrosylation, which is mediated by nitric oxide (NO). This study is to determine the role of Akt S-Nitrosylation in the recovery of heart functions after ischaemia. In recombinant Akt protein and in HEK293 cells, NO donor decreased Akt activity and induced Akt S-Nitrosylation, but was abolished if Akt protein was mutated by replacing cysteine 296/344 with alanine (Akt-C296/344A). In endothelial cells, NO induced Akt S-Nitrosylation, reduced Akt activity and damaged multiple cellular functions including proliferation, migration and tube formation. These alterations were ablated if cells expressed Akt-C296/344A mutant. In Apoe-/- mice, nitroglycerine infusion increased both Akt S-Nitrosylation and infarct size, reduced Akt activity and capillary density, and delayed the recovery of cardiac function in ischaemic hearts, compared with mice infused with vehicle. Importantly, these in vivo effects of nitroglycerine in Apoe-/- mice were remarkably prevented by adenovirus-mediated enforced expression of Akt-C296/344A mutant. In conclusion, long-term usage of organic nitrate may inactivate Akt to delay ischaemia-induced revascularization and the recovery of cardiac function through NO-mediated S-Nitrosylation.
Assuntos
Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Revascularização Miocárdica , Nitratos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adenoviridae/metabolismo , Sequência de Aminoácidos , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisteína/metabolismo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Mutação/genética , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Nitroglicerina/farmacologia , Nitroprussiato/farmacologia , NitrosaçãoRESUMO
AIMS: We have previously reported that nano-selenium quantum dots (SeQDs) prevented endothelial dysfunction in atherosclerosis. This study is to investigate whether amorphous SeQDs (A-SeQDs) increase endogenous tetrahydrobiopterin biosynthesis to alleviate pulmonary arterial hypertension. RESULTS: Both A-SeQDs and C-SeQDs were stable under physiological conditions, while the size of A-SeQDs was smaller than C-SeQDs by high resolution-transmission electron microscopy scanning. In monocrotaline-injected mice, oral administration of A-SeQDs was more effective to decrease pulmonary arterial pressure, compared to C-SeQDs and organic selenium. Further, A-SeQDs increased both nitric oxide productions and intracellular BH4 levels, upregulated dihydrofolate reductase activity in lungs, and improved pulmonary arterial remodeling. Gene deletion of dihydrofolate reductase abolished these effects produced by A-SeQDs in mice. Finally, the blood levels of tetrahydrobiopterin and selenium were decreased in patients with pulmonary arterial hypertension. CONCLUSION: A-SeQDs increase intracellular tetrahydrobiopterin to prevent pulmonary arterial hypertension through recoupling endothelial nitric oxide synthase. METHODS: Two polymorphs of SeQDs and A-SeQDs, and a crystalline form of SeQDs (C-SeQDs) were prepared through self-redox decomposition of selenosulfate precursor. Mice were injected with monocrotaline to induce pulmonary arterial hypertension in vivo. Pulmonary arterial pressure was measured.
Assuntos
Óxido Nítrico Sintase Tipo III/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , Pontos Quânticos/química , Selênio , Idoso , Idoso de 80 Anos ou mais , Animais , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Tamanho da Partícula , Selênio/química , Selênio/farmacologiaRESUMO
Macrophage activation participates in the pathogenesis of pulmonary inflammation. As a coenzyme, vitamin B6 (VitB6) is mainly involved in the metabolism of amino acids, nucleic acids, glycogen and lipids. We have previously reported that activation of AMP-activated protein kinase (AMPK) produces anti-inflammatory effects both in vitro and in vivo. Whether VitB6 via AMPK activation prevents pulmonary inflammation remains unknown. The model of acute pneumonia was induced by injecting mice with lipopolysaccharide (LPS). The inflammation was determined by measuring the levels of interleukin-1 beta (IL-1ß), IL-6 and tumour necrosis factor alpha (TNF-α) using real time PCR, ELISA and immunohistochemistry. Exposure of cultured primary macrophages to VitB6 increased AMP-activated protein kinase (AMPK) Thr172 phosphorylation in a time/dose-dependent manner, which was inhibited by compound C. VitB6 downregulated the inflammatory gene expressions including IL-1ß, IL-6 and TNF-α in macrophages challenged with LPS. These effects of VitB6 were mirrored by AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR). However, VitB6 was unable to inhibit LPS-induced macrophage activation if AMPK was in deficient through siRNA-mediated approaches. Further, the anti-inflammatory effects produced by VitB6 or AICAR in LPS-treated macrophages were abolished in DOK3 gene knockout (DOK3-/- ) macrophages, but were enhanced in macrophages if DOK3 was overexpressed. In vivo studies indicated that administration of VitB6 remarkably inhibited LPS-induced both systemic inflammation and acute pneumonia in wild-type mice, but not in DOK3-/- mice. VitB6 prevents LPS-induced acute pulmonary inflammation in mice via the inhibition of macrophage activation.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Interleucina-1beta/genética , Pneumonia/tratamento farmacológico , Fator de Necrose Tumoral alfa/genética , Vitamina B 6/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Modelos Animais de Doenças , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Ativação de Macrófagos/efeitos dos fármacos , Camundongos , Fosforilação/efeitos dos fármacos , Pneumonia/induzido quimicamente , Pneumonia/genética , Pneumonia/patologia , Transdução de SinaisRESUMO
Cardiac fibrosis is a key factor to determine the prognosis in patient with myocardial infarction (MI). The aim of this study is to investigate whether the transcriptional factor paired-related homeobox 2 (Prrx2) regulates Wnt5a gene expression and the role in myocardial fibrosis following MI. The MI surgery was performed by ligation of left anterior descending coronary artery. Cardiac remodelling was assessed by measuring interstitial fibrosis performed with Masson staining. Cell differentiation was examined by analysis the expression of alpha-smooth muscle actin (α-SMA). Both Prrx2 and Wnt5a gene expressions were up-regulated in mice following MI, accompanied with increased mRNA and protein levels of α-SMA, collagen I and collagen III, compared to mice with sham surgery. Adenovirus-mediated gene knock down of Prrx2 increased survival rate, alleviated cardiac fibrosis, decreased infarction sizes and improved cardiac functions in mice with MI. Importantly, inhibition of Prrx2 suppressed ischaemia-induced Wnt5a gene expression and Wnt5a signalling. In cultured cardiac fibroblasts, TGF-ß increased gene expressions of Prrx2 and Wnt5a, and induced cell differentiations, which were abolished by gene silence of either Prrx2 or Wnt5a. Further, overexpression of Prrx2 or Wnt5a mirrored the effects of TGF-ß on cell differentiations of cardiac fibroblasts. Gene silence of Wnt5a also ablated cell differentiations induced by Prrx2 overexpression in cardiac fibroblasts. Mechanically, Prrx2 was able to bind with Wnt5a gene promoter to up-regulate Wnt5a gene expression. In conclusions, targeting Prrx2-Wnt5a signalling should be considered to improve cardiac remodelling in patients with ischaemic heart diseases.