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Research suggests that ischemic glycolysis improves myocardial tolerance to anoxia and low-flow ischemia. The rate of glycolysis during ischemia reflects the severity of the injury caused by ischemia and subsequent functional recovery following reperfusion. Histone H2AK119 ubiquitination (H2Aub) is a common modification that is primarily associated with gene silencing. Recent studies have demonstrated that H2Aub contributes to the development of cardiovascular diseases. However, the underlying mechanism remains unclear. This study identified Hsp27 (heat shock protein 27) as a H2Aub binding protein and explored its involvement in mediating glycolysis and mitochondrial function. Functional studies revealed that inhibition of PRC1 (polycomb repressive complex 1) decreased H2Aub occupancy and promoted Hsp27 expression through inhibiting ubiquitination. Additionally, it increased glycolysis by activating the NF-κB/PFKFB3 signaling pathway during myocardial ischemia. Furthermore, Hsp27 reduced mitochondrial ROS production by chaperoning COQ9, and suppressed ferroptosis during reperfusion. A delivery system was developed based on PCL-PEG-MAL (PPM)-PCM-SH (CWLSEAGPVVTVRALRGTGSW) to deliver PRT4165 (PRT), a potent inhibitor of PRC1, to damaged myocardium, resulting in decreased H2Aub. These findings revealed a novel epigenetic mechanism connecting glycolysis and ferroptosis in protecting the myocardium against ischemia/reperfusion injury.
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Cardiac microvascular dysfunction contributes to cardiac hypertrophy (CH) and can progress to heart failure. Lutein is a carotenoid with various pharmacological properties, such as anti-apoptotic, anti-inflammatory, and antioxidant effects. Limited research has been conducted on the effects of lutein on pressure overload-induced CH. Studies have shown that CH is accompanied by ferroptosis in the cardiac microvascular endothelial cells (CMECs). This study aimed to investigate the effect of lutein on ferroptosis of CMECs in CH. The transcription factor interferon regulatory factor (IRF) is associated with immune system function, tumor suppression, and apoptosis. The results of this study suggested that pressure overload primarily inhibits IRF expression, resulting in endothelial ferroptosis. Administration of lutein increased the expression of IRF, providing protection to endothelial cells during pressure overload. IRF silencing downregulated solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) expression, leading to the induction of ferroptosis in CMECs. Lutein supplementation suppressed endothelial ferroptosis by upregulating IRF. These data suggest that IRF may function as a transcription factor for SLC7A11 and that lutein represses ferroptosis in CMECs by upregulating IRF expression. Therefore, targeting IRF may be a promising therapeutic strategy for effective cardioprotection in patients with CH and heart failure.
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Ferroptose , Insuficiência Cardíaca , Humanos , Células Endoteliais , Luteína/farmacologia , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/farmacologia , Células Cultivadas , Cardiomegalia/metabolismo , Insuficiência Cardíaca/patologiaRESUMO
Electroreduction of CO2 to valuable chemicals powered by renewable electricity provides a sustainable approach to reduce the environmental issues originating from CO2 emission. However, insufficient current density and production selectivity hinder its further application. In this case, precisely regulating the CO2 reduction reaction (CO2RR) active sites is an excellent strategy to simultaneously reduce the reaction barrier and suppress the hydrogen evolution reaction (HER) pathway. Herein, the strain regulation of atomically dispersed NiN4 active sites is investigated in helical carbon. Ni-N coordination in the curved carbon lattice displays a reduced distance compared to that in a straight lattice, inflicting local compressive strain on NiN4. The resultant catalyst shows the highest CO selectivity of up to 99.4% at -1.4 V (vs. RHE), the FECO is maintained at over 85% over a wide potential range from -0.8 to -1.8 V (vs. RHE), and the maximum partial current density for CO reaches a high of 458 mA cm-2 at -1.8 V (vs. RHE). Theoretical investigations show the superior CO2 electroreduction performance of curved NiN4 stems from its remarkable ability to generate the *COOH intermediate and to suppress the hydrogen combination simultaneously. Our findings offer a novel strategy to rationally regulate the local three-dimensional structure of single-atom sites for efficient electrocatalysis.
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The aim of this study is to examine the long-term effects of prenatal and early-life WIFI signal exposure on neurodevelopment and behaviors as well as biochemical alterations of Wistar rats. On the first day of pregnancy (E0), expectant rats were allocated into two groups: the control group (n = 12) and the WiFi-exposed group (WiFi group, n = 12). WiFi group was exposed to turn on WiFi for 24 h/day from E0 to postnatal day (PND) 42. The control group was exposed to turn-off WiFi at the same time. On PND7-42, we evaluated the development and behavior of the offspring, including body weight, pain threshold, and swimming ability, spatial learning, and memory among others. Also, levels of proteins involved in apoptosis were analyzed histologically in the hippocampus in response to oxidative stress. The results showed that WiFi signal exposure in utero and early life (1) increased the body weight of WiFi + M (WiFi + male) group; (2) no change in neuro-behavioral development was observed in WiFi group; (3) increased learning and memory function in WiFi + M group; (4) enhanced comparative levels of BDNF and p-CREB proteins in the hippocampus of WiFi + M group; (5) no neuronal loss or degeneration was detected, and neuronal numbers in hippocampal CA1 were no evidently differences in each group; (6) no change in the apoptosis-related proteins (caspase-3 and Bax) levels; and (7) no difference in GSH-PX and SOD activities in the hippocampus. Prenatal WiFi exposure has no effects on hippocampal CA1 neurons, oxidative equilibrium in brain, and neurodevelopment of rats. Some effects of prenatal WiFi exposure are sex dependent. Prenatal WiFi exposure increased the body weight, improved the spatial memory and learning function, and induced behavioral hyperactivity of male rats.
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Aprendizagem , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Feminino , Ratos , Masculino , Animais , Humanos , Ratos Wistar , Encéfalo/metabolismo , Estresse Oxidativo , Hipocampo , Peso Corporal , Efeitos Tardios da Exposição Pré-Natal/metabolismoRESUMO
Long non-coding RNAs (lncRNAs) are expressed aberrantly in cardiac disease, but their roles in cardiac hypertrophy are still unknown. Here we sought to identify a specific lncRNA and explore the mechanisms underlying lncRNA functions. Our results revealed that lncRNA Snhg7 was a super-enhancer-driven gene in cardiac hypertrophy by using chromatin immunoprecipitation sequencing (ChIP-seq). We next found that lncRNA Snhg7 induced ferroptosis by interacting with T-box transcription factor 5 (Tbx5), a cardiac transcription factor. Moreover, Tbx5 bound to the promoter of glutaminase 2 (GLS2) and regulated cardiomyocyte ferroptosis activity in cardiac hypertrophy. Importantly, extra-terminal domain inhibitor JQ1 could suppress super-enhancers in cardiac hypertrophy. Inhibition of lncRNA Snhg7 could block the expressions of Tbx5, GLS2 and levels of ferroptosis in cardiomyocytes. Furthermore, we verified that Nkx2-5 as a core transcription factor, directly bound the super-enhancer of itself and lncRNA Snhg7, increasing both of their activation. Collectively, we are the first to identify lncRNA Snhg7 as a novel functional lncRNA in cardiac hypertrophy, might regulate cardiac hypertrophy via ferroptosis. Mechanistically, lncRNA Snhg7 could transcriptionally regulate Tbx5/GLS2/ferroptosis in cardiomyocytes.
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Ferroptose , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/metabolismo , Cardiomegalia/genética , Cardiomegalia/metabolismo , Fatores de Transcrição/metabolismo , Miócitos Cardíacos/metabolismo , MicroRNAs/genética , Glutaminase/metabolismoRESUMO
Hepatic ischemia-reperfusion (I/R) injury is a multifactorial process caused by transient tissue hypoxia and the following reoxygenation, commonly occurring in liver transplantation and hepatectomy. Hepatic I/R can induce a systemic inflammatory response, liver dysfunction, or even multiple organ failure. Although we have previously reported that taurine could attenuate acute liver injury after hepatic I/R, only a tiny proportion of the systemically injected taurine could reach the targeted organ and tissues. In this present study, we prepared taurine nanoparticles (Nano-taurine) by coating taurine with neutrophil membranes and investigated the protective effects of Nano-taurine against I/R-induced injury and the underlying mechanisms. Our results showed that Nano-taurine restored liver function by declining AST and ALT levels and reducing histology damage. Nano-taurine decreased inflammatory cytokines, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, intercellular adhesion molecule (ICAM)-1, NLR pyrin domain containing 3 (NLRP3) and apoptosis-associated speck-like protein containing CARD (ASC) and oxidants including superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), catalase (CAT) and reactive oxygen species (ROS), exhibiting anti-inflammatory and antioxidant properties. The expression of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) was increased, while prostaglandin-endoperoxide synthase 2 (Ptgs2) was decreased upon administration of Nano-taurine, suggesting that inhibiting ferroptosis may be involved in the mechanism during hepatic I/R injury. These results suggest that Nano-taurine have a targeted therapeutic effect on hepatic I/R injury by inhibiting inflammation, oxidative stress, and ferroptosis.
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Hepatopatias , Traumatismo por Reperfusão , Humanos , Taurina/farmacologia , Taurina/uso terapêutico , Neutrófilos/metabolismo , Fígado , Hepatopatias/patologia , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Glutationa/metabolismo , Interleucina-6/metabolismo , Traumatismo por Reperfusão/metabolismoRESUMO
BACKGROUND: Angiogenesis is an essential physiological process in the growth and metastasis of primary tumors. Ca2+ signaling is crucial for tumor angiogenesis. The purpose of this study was to detect the potential role of Ca2+ permeable transient receptor potential vanilloid-3 (TRPV3) in the angiogenesis of non-small cell lung cancer (NSCLC). METHODS: Small interfering RNA was used to down-regulate TRPV3 expression in A549 cells. A laser scanning confocal microscope was used to examine intracellular calcium concentration ([Ca2+]i). Human umbilical vein endothelial cells (HUVECs) tube formation and migration assay, Western blot, MTT and ELISA were performed to detect the potential mechanisms of TRPV3 in tumor angiogenesis. A mouse tumor xenograft model was performed to expound the effects of TRPV3 on tumor cell growth. RESULTS: Inhibition of TRPV3 reduced [Ca2+]i and protein expressions of VEGF and HIF-1α in A549 cells. Moreover, HIF-1α depletion decreased the secretion and expression of VEGF. Depletion of TRPV3 inhibited HUVECs proliferation, tube formation and migration induced by conditioned medium. And TRPV3 inhibition could decrease the volume of xenograft tumors and MVD of CD34+ cells. The expression levels of HIF-1α, VEGF and p-CaMKÐ in the xenograft tumors in RuR and siTRPV3 groups was reduced. CONCLUSIONS: TRPV3 calcium channel protein may play a key role in NSCLC angiogenesis. TRPV3 could promote the angiogenesis through HIF-1α-VEGF signaling pathway. Targeting TRPV3 channel protein by novel approaches would be useful for reversing NSCLC angiogenesis.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Camundongos , Animais , Células A549 , Fator A de Crescimento do Endotélio Vascular/genética , Transdução de Sinais , Células Endoteliais da Veia Umbilical Humana , Canais de Cátion TRPV/genéticaRESUMO
Autism spectrum disorder (ASD) refers to a group of neurodevelopmental disorders. The etiology and pathological mechanisms of ASD are still unknown, and its prognosis is poor. This study investigated the effects of selenium (Se) supplementation on abnormal behavior and cognitive function in ASD model mice, as well as the potential action pathways. BTBR mice were randomly assigned to either a model group (BTBR group), a model selenium supplement group (BTBR+Se group), a normal control group (B6 group) or a normal selenium supplement group (B6+Se group). Sodium selenite, at a dosage of 1 mg/kg/day, was administered to the selenium supplementation groups by gavage. The mice in the BTBR group and the B6 group received the same amount of 0.9% saline by gavage. After 4 weeks of continuous intervention, the social functions and cognitive behaviors of the mice and the selenium concentration in hippocampal tissue were assessed. Hippocampal tissue structures were observed. Changes in neurotransmitter levels, oxidative stress and neuroinflammatory indicators were detected. SelP protein expression was significantly lower in hippocampal tissue from BTBR mice than in hippocampal tissue from B6 mice. The administration of sodium selenite in BTBR mice: (1) increased the expression of SelP; (2) attenuated spatial learning, memory impairment and improved social behaviors; (3) changed the serum levels of 5-HT, DA and Glu; (4) decreased the levels of inflammatory cytokines IL-6, IL-1ß, and TNF-α in serum and hippocampal tissue; (5) reduced the ROS and MDA contents and significantly increased SOD activity, CAT activity, GSH-px activity, and antioxidant GSH levels; and (6) protected against neuronal loss in the hippocampus. Se supplementation significantly improved the social functioning, repetitive stereotyped behavior and cognitive function in BTBR mice. Se may play a protective role in the hippocampus of BTBR mice by regulating neurotransmitter levels, reducing oxidative stress, alleviating neuroinflammation and rescuing neural cell damage.
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Transtorno do Espectro Autista , Transtorno Autístico , Selênio , Animais , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/etiologia , Suplementos Nutricionais , Modelos Animais de Doenças , Expressão Gênica , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos , Estresse Oxidativo , Selênio/farmacologia , Comportamento Social , Selenito de SódioRESUMO
Pathway analysis is considered as an important strategy to reveal the underlying mechanisms of diseases. Pathways that are involved in crosstalk can regulate each other and co-regulate downstream biological processes. Furthermore, some genes in the pathways can function with other genes via the relationship of the competing endogenous RNA (ceRNA) mechanism, which has also been demonstrated to play key roles in cellular biology. However, the comprehensive analysis of ceRNA-mediated pathway crosstalk is lacking. Here, we constructed the landscape of the ceRNA-mediated pathway-pathway crosstalk of eight major cardiovascular diseases (CVDs) based on sequencing data from â¼2,800 samples. Some common features shared by numerous CVDs were uncovered. A fraction of the pathway-pathway crosstalk was conserved in multiple CVDs and a core pathway-pathway crosstalk network was identified, suggesting the similarity of pathway-pathway crosstalk among CVDs. Experimental evidence also demonstrated that the pathway crosstalk was functioned in CVDs. We split all hub pathways of each pathway-pathway crosstalk network into three categories, namely, common hubs, differential hubs, and specific hubs, which could highlight the common or specific biological mechanisms. Importantly, after a comparison analysis of the hub pathways of networks, â¼480 hub pathway-induced common modules were identified to exert functions in CVDs broadly. Moreover, we performed a random walk algorithm on the hub pathway-induced sub-network and identified 23 potentially novel CVD-related pathways. In summary, our study revealed the potential molecular regulatory mechanisms of ceRNA crosstalk in pathway-pathway crosstalk levels and provided a novel routine to investigate the pathway-pathway crosstalk in cardiology. All CVD pathway-pathway crosstalks are provided in http://www.licpathway.net/cepathway/index.html.
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BACKGROUND: Autism spectrum disorder (ASD) is a group of extensive neurodevelopmental disorders for which few efficacious drugs are available. Sodium selenite (Se), the most common inorganic form of selenium given to humans and animals, has antioxidant, anti-inflammatory, and neuroprotective effects in several psychiatric and neurological disorders. However, the effect of Se on ASD is unclear. METHODS: Using the BTBR T + tf/J (BTBR) mouse model of ASD, we investigated the therapeutic effects and underlying mechanism of action of Se on ASD. BTBR mice were randomly divided into four groups: BTBR, BTBR+Se, BTBR+Se+ML385, and BTBR+Se+RSL3. The normal control group was composed of C57BL/6 (B6) mice. Se, Nuclear factor erythroid 2-related factor 2 (Nrf2), and glutathione peroxidase 4 (GPx4) inhibitors were administered separately for 28 days using oral gavage. After 28 days, social behavior, ferroptosis indices, and gene and protein expression levels for components of the Nrf2/GPx4 pathway were assessed to explore the correlation between Se levels and ASD. RESULTS: We demonstrated that Se significantly mitigated impairments in learning and memory, improved social functions, reduced repetitive behaviors, and inhibited ferroptosis in the CA1 area of the hippocampus. We also found that the Nrf2/GPX4 pathway was a target for Se. Treatment with Se increased levels of Nrf2 and GPX4. The Nrf2 inhibitor ML385 reduced the effect of Se on ferroptosis and abnormal behaviors in BTBR mice. In addition, the GPx4 inhibitor RSL3 revealed similar efficacy to ML385 CONCLUSION: We determined that Se exhibited a beneficial effect on autism-relevant behaviors and inhibited ferroptosis in the BTBR mouse model of ASD, possibly through modulation of the Nrf2/GPX4 signaling pathway.
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Transtorno do Espectro Autista , Transtorno Autístico , Ferroptose , Selênio , Animais , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno Autístico/tratamento farmacológico , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Selênio/farmacologia , Selênio/uso terapêuticoRESUMO
The molecular characteristics of ferroptosis in cardiac hypertrophy have been rarely studied. Especially, there have been no studies to investigate the regulatory mechanisms of docosahexaenoic acid (DHA) on ferroptosis in cardiac hypertrophy. This study was designed to determine the role of ferroptosis in microvascular injury, and investigate the contribution of DHA in suppressing ferroptosis and preventing pressure overload-mediated endothelial damage. Our results indicated that the expression of interferon regulating factor 3 (IRF3) was primarily inhibited by pressure overload and consequently caused endothelial ferroptosis. Nevertheless, administration of DHA increased IRF3 expression and provided a pro-survival advantage for the endothelial system in the context of pressure overload. Experimental studies clearly showed that inhibition of IRF3 down-regulated SLC7A11 expression, and the latter leaded to the increase in the activities of arachidonate 12-lipoxygenase, which obligated cardiac microvascular endothelial cells to undergo ferroptosis via augmenting lipid peroxides. Interestingly, DHA supplementation suppressed endothelial ferroptosis via up-regulation of IRF3. Taken together, our studies identified the IRF3-SLC7A11-arachidonate 12-lipoxygenase axis as a new pathway responsible for pressure overload-mediated microvascular damage via initiating endothelial ferroptosis. In contrast, DHA treatment up-regulated the expression of IRF3 and thus reduced cellular ferroptosis, conferring a protective advantage to the endothelial system in pressure overload. These findings revealed that targeting IRF3 might be a useful therapeutic strategy for cardioprotection in cardiac hypertrophy and heart failure.
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Ferroptose , Animais , Araquidonato 12-Lipoxigenase , Cardiomegalia/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/farmacologia , Células Endoteliais , Interferons , Ratos , Regulação para CimaRESUMO
Cardiac microvascular dysfunction is associated with cardiac hypertrophy and can eventually lead to heart failure. Dysregulation of long non-coding RNAs (lncRNAs) has recently been recognized as one of the key mechanisms involved in cardiac hypertrophy. However, the potential roles and underlying mechanisms of lncRNAs in cardiac microvascular dysfunction have not been explicitly delineated. Our results confirmed that cardiac microvascular dysfunction was related to cardiac hypertrophy and ferroptosis of cardiac microvascular endothelial cells (CMECs) occurred during cardiac hypertrophy. Using a combination of in vivo and in vitro studies, we identified a lncRNA AABR07017145.1, named as lncRNA AAB for short, and revealed that lncRNA AAB was upregulated in the hearts of cardiac hypertrophy rats as well as in the Ang II-induced CMECs. Importantly, we found that lncRNA AAB sponged and sequestered miR-30b-5p to induce the imbalance of MMP9/TIMP1, which enhanced the activation of transferrin receptor 1 (TFR-1) and then eventually led to the ferroptosis of CMECs. Moreover, we have developed a delivery system based on neutrophil membrane (NM)-camouflaged mesoporous silica nanocomplex (MSN) for inhibition of cardiac hypertrophy, indicating the potential role of silenced lncRNA AAB (si-AAB) and overexpressed miR-30b-5p as the novel therapy for cardiac hypertrophy.
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In recent years, with the development of nanomaterials, a slice of nanomaterials has been demonstrated to possess high catalytic activity similar to natural enzymes and counter the dilemmas including easy inactivation and low yield natural of enzymes, which are labeled as nanozymes. The catalytic activity of nanozymes could be easily regulated by size, structure, surface modification and other factors. In comparison with natural enzymes, nanozymes featured with a more stable structure, economical preparation and preservation, diversity of functions and adjustable catalytic activity, thus becoming the potentially ideal substitute for natural enzymes. Generally, the are mainly three types containing metal oxide nanozymes, noble metal nanozymes and carbon-based nanozymes, owing various applications in biomedical, energy and environmental fields. In this review, to summarize the recent representative applications of nanozymes, and potentially explore the scientific problems in this field at the same time, we are going to discuss the catalytic mechanisms of diverse nanozymes, with the emphasis on their applications in the fields of tumor therapy, anti-inflammatory and biosensing, hoping to help and guide the future development of nanozymes.
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Cardiac microvascular endothelial cells (CMECs), derived from coronary circulation microvessel, are the main barrier for the exchange of energy and nutrients between myocardium and blood. However, microvascular I/R injury is a severely neglected topic, and few strategies can reverse this pathology. In this study, we investigated the mechanism of shear stress in microvascular I/R injury, and try to elucidate the downstream signaling pathways that inhibit CMECs apoptosis to reduce I/R injury. Our results demonstrated that shear stress inhibited the apoptosis protein, increased PECAM-1 expression and eNOS phosphorylation in hypoxia reoxygenated (H/R) CMECs. The mechanism of shear stress was related to up-regulated expression of YAP, the increased number of YAP entering the nucleus by dephosphorylation, the reduced number of TUNEL positive cells, increased miR-206 and inhibited protein level of PDCD4 in CMECs. However, siRNA-mediated knockdown of YAP abolished the protective effects of shear stress on CMECs apoptosis, similar results obtained from administration with AMO-miR-206, and also prevented PDCD4 (target gene of miR-206) increasing when treatment with both AMO-miR-206 and mimics-miR-206. In vivo, restoring the blood fluid with nitroglycerin (NTG) to mimic in vitro shear stress levels, which subsequently improved cardiac function, reduced infarcted area, lowered microvascular perfusion defects. Functional investigations clearly illustrated that increased the protein expression of PECAM-1 and eNOS phosphorylation, activated YAP, strengthened miR-206 expression, and suppressed PDCD4 expression. In summary, this study confirmed that shear stress reversed CMECs apoptosis, relieved microvascular I/R injury, the mechanism of which involving through YAP/miR-206/PDCD4 signaling pathway to finally suppress myocardial I/R injury.
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Proteínas Reguladoras de Apoptose/metabolismo , Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/metabolismo , Microvasos/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Resistência ao Cisalhamento/fisiologia , Animais , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Sobrevivência Celular/fisiologia , Células Cultivadas , Células HEK293 , Humanos , Masculino , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia , Proteínas de Sinalização YAPRESUMO
Emerging evidence reveals that autophagy plays crucial roles in cardiac hypertrophy. Long noncoding RNAs (lncRNAs) are novel transcripts that function as gene regulators. However, it is unclear whether lncRNAs regulate autophagy in cardiac hypertrophy. Here, we identified a novel transcript named lncRNA Gm15834, which was upregulated in the transverse aortic constriction (TAC) model in vivo and the angiotensin-II (Ang-II)-induced cardiac hypertrophy model in vitro and was regulated by nuclear factor kappa B (NF-κB). Importantly, forced expression of lncRNA Gm15834 enhanced autophagic activity of cardiomyocytes and promoted myocardial hypertrophy, whereas silencing of lncRNA Gm15834 attenuated autophagy-induced myocardial hypertrophy. Mechanistically, we found that lncRNA Gm15834 could function as an endogenous sponge RNA of microRNA (miR)-30b-3p, which was downregulated in cardiac hypertrophy. Inhibition of miR-30b-3p enhanced cardiomyocyte autophagic activity and aggravated myocardial hypertrophy, whereas overexpression of miR-30b-3p suppressed autophagy-induced myocardial hypertrophy by targeting the downstream autophagy factor of unc-51-like kinase 1 (ULK1). Moreover, inhibition of lncRNA Gm15834 by adeno-associated virus carrying short hairpin RNA (shRNA) suppressed cardiomyocyte autophagic activity, improved cardiac function, and mitigated cardiac hypertrophy. Taken together, our study identified a novel regulatory axis encompassing lncRNA Gm15834/miR-30b-3p/ULK1/autophagy in cardiac hypertrophy, which may provide a potential therapy target for cardiac hypertrophy.
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Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia , Cardiomegalia/terapia , Regulação da Expressão Gênica , RNA Longo não Codificante/antagonistas & inibidores , Angiotensina II/toxicidade , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Cardiomegalia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais , Vasoconstritores/toxicidadeRESUMO
Most sound imaging instruments are currently used as measurement tools which can provide quantitative data, however, a uniform method to directly and comprehensively evaluate the results of combining acoustic and optical images is not available. Therefore, in this study, we define a localization error index for sound imaging instruments, and propose an acoustic phase cloud map evaluation method based on an improved YOLOv4 algorithm to directly and objectively evaluate the sound source localization results of a sound imaging instrument. The evaluation method begins with the image augmentation of acoustic phase cloud maps obtained from the different tests of a sound imaging instrument to produce the dataset required for training the convolutional network. Subsequently, we combine DenseNet with existing clustering algorithms to improve the YOLOv4 algorithm to train the neural network for easier feature extraction. The trained neural network is then used to localize the target sound source and its pseudo-color map in the acoustic phase cloud map to obtain a pixel-level localization error. Finally, a standard chessboard grid is used to obtain the proportional relationship between the size of the acoustic phase cloud map and the actual physical space distance; then, the true lateral and longitudinal positioning error of sound imaging instrument can be obtained. Experimental results show that the mean average precision of the improved YOLOv4 algorithm in acoustic phase cloud map detection is 96.3%, the F1-score is 95.2%, and detection speed is up to 34.6 fps. The improved algorithm can rapidly and accurately determine the positioning error of sound imaging instrument, which can be used to analyze and evaluate the positioning performance of sound imaging instrument.
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Cardiac hypertrophy, a response of the heart to increased workload, is a major risk factor for heart failure. Myostatin (MSTN) is an inhibitor of myogenesis, regulating the number and size of skeletal myocytes. In recent years, cardiomyocyte autophagy also has been considered to be involved in controlling the hypertrophic response. However, less is known about the detailed mechanism of MSTN on cardiac hypertrophy via regulation of cardiomyocyte autophagy. In this study, we found that the deletion of MSTN potentiated abdominal aorta coarctation (AAC) and angiotensin II (Ang II)-induced pathological cardiac hypertrophy and cardiac autophagy; however, AAC and Ang II-induced cardiac hypertrophic phenotype and cardiac autophagy were dramatically diminished by MSTN in vivo and in vitro. Mechanistically, the anti-hypertrophic and anti-autophagic effects mediated by MSTN in response to pathological stimuli were associated with the direct inactivation of activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) and activation of the peroxisome proliferator-activated receptor gamma (PPARγ)/nuclear factor κB (NF-κB) signaling pathway. Additionally, miR-128 aggravated the progression of cardiac hypertrophy through suppressing its target PPARγ. Furthermore, MSTN downregulated miR-128 expression induced by AAC and Ang II. Taken together, MSTN significantly blunts pathological cardiac hypertrophy and dysfunction, at least in part, by inhibiting excessive cardiac autophagy via blocking AMPK/mTOR and miR-128/PPARγ/NF-κB signaling pathways.
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Microvessel hypoperfusion following ischemic stress resulted in a decreased shear stress of brain microvascular endothelial cells (BMECs) and contributed to abnormal expression of PECAM-1 after global cerebral ischemia/reperfusion (I/R) injury. Here, we identified novel pathophysiologic and rehabilitative procedures specific to shear stress in microvascular endothelial cells in response to global cerebral I/R injury. We found that the decrease in cerebral blood flow of gerbils after global cerebral I/R injury reduces shear stress, and the abnormal change in shear stress leads to microvascular endothelial cell and neuron damage. Nevertheless, suitable high levels of shear stress contribute to rescuing the dysfunction and malformation of BMECs via regulating the PECAM-1-eNOS-NO pathway to enhance nitric oxide release, decrease the expression of caspase-3 to reduce apoptosis, and improve the shear-adaptability of endothelial cells, thereby playing a protective role in the gerbil brain.
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OBJECTIVE: Cerebral ischemia is the most common type of neuronal injury and is characterized by a reduction in the function and number of hippocampal neurons. Carvacrol has a significant neuroprotective effect in cerebral ischemia. However, the mechanisms by which carvacrol affects cerebral ischemia, especially with respect to the regulation of neuronal damage by iron levels, have never been systematically studied. This study aimed to reveal the mechanisms by which carvacrol protects against hippocampal neuron impairment after ischemic stroke in gerbils. MATERIALS AND METHODS: The Morris water maze test was performed to evaluate learning and memory impairments. Iron ion content and oxidative stress index were detected by the kit. MTT assay was performed to assess the cell viability. The morphology and molecular characteristics were detected by electron micrographs and western blot. RESULTS: In the present study, we demonstrated the neuroprotective effects of carvacrol in vivo and in vitro. The Morris water maze test showed that the learning and memory abilities of the gerbils treated with carvacrol were significantly improved. Lipid peroxide injury was evaluated by measuring the levels of lipid peroxide biomarkers; the results indicated that carvacrol decreased the level of lipid peroxide in ischemic gerbil brain tissue. Histopathological examinations and western blotting were performed to evaluate injury in neurons, and carvacrol reduced cell death. Moreover, ferroptosis in the hippocampus was evaluated by measuring the levels of proteins involved in this iron-dependent form of regulated cell death. These results indicated that carvacrol reduced cell death and that carvacrol inhibited ferroptosis by increasing the expression of glutathione peroxidase 4(GPx4). This study showed that carvacrol may be a valuable drug for treating cerebral ischemia. CONCLUSION: Carvacrol provides protection for hippocampal neurons against I/R in gerbils by inhibiting ferroptosis through increasing the expression of GPx4.
Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/fisiopatologia , Hipocampo/efeitos dos fármacos , Monoterpenos/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Cimenos , Gerbillinae , Glutationa Peroxidase/metabolismo , Hipocampo/patologia , Masculino , Neurônios/patologia , Estresse Oxidativo , Fosfolipídeo Hidroperóxido Glutationa PeroxidaseRESUMO
The aim of this study was to examine the effects of folic acid (FA) on the autistic phenotypes in BTBR T+ Itpr3tf/J (BTBR) mice and to investigate underlying mechanisms. Mice received FA (0.2 mg/kg/day) orally from postnatal days 14 to 35. Mice were then tested for stereotyped and repetitive behaviors, social interaction, and spatial learning and memory at the end of FA supplementation. Oxidative stress, neuroinflammatory responses and ferroptosis-related proteins in the brain were also evaluated. FA supplementation in BTBR mice reduced repetitive and stereotyped behavior, improved social communication, and enhanced memory and spatial learning. FA supplementation also reduced neuronal loss in hippocampal CA1 regions of the brain and decreased the levels of the proinflammatory cytokines such as interleukin-1ß (IL-1ß), Iba-1, IL-18, tumor necrosis factor-a, and IL-6 and glial fibrillary acidic protein in the hippocampus. FA supplementation changed the malondialdehyde and glutathione levels and superoxide dismutase (SOD) and glutathione peroxidase activities in the hippocampus. FA supplementation inhibited the elevation of the SOD1 and TFR protein levels and enhanced the relative expression levels of glutathione peroxidase 4 and ferroportin 1 in the hippocampus and increased the relative levels of phospho-Ca2+/calmodulin-dependent protein kinase II and phospho-cAMP-response element binding protein in the hippocampus. FA oral supplementation to BTBR mice rescued stereotyped and repetitive behaviors, social deficit, and spatial learning and memory impairments, likely by improving the oxidative-stress and inflammatory responses by altering the ferroptosis signaling pathways.