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BACKGROUND: Hyperglycemia-a symptom that characterizes diabetes-is highly associated with atherothrombotic complications. However, the underlying mechanism by which hyperglycemia fuels platelet activation and arterial thrombus formation is still not fully understood. METHODS: The profiles of polyunsaturated fatty acid metabolites in the plasma of patients with diabetes and healthy controls were determined with targeted metabolomics. FeCl3-induced carotid injury model was used to assess arterial thrombus formation in mice with endothelial cell (EC)-specific YAP (yes-associated protein) deletion or overexpression. Flow cytometry and clot retraction assay were used to evaluate platelet activation. RNA sequencing and multiple biochemical analyses were conducted to unravel the underlying mechanism. RESULTS: The plasma PGE2 (prostaglandin E2) concentration was elevated in patients with diabetes with thrombotic complications and positively correlated with platelet activation. The PGE2 synthetases COX-2 (cyclooxygenase-2) and mPGES-1 (microsomal prostaglandin E synthase-1) were found to be highly expressed in ECs but not in other type of vessel cells in arteries from both patients with diabetes and hyperglycemic mice, compared with nondiabetic individuals and control mice, respectively. A combination of RNA sequencing and ingenuity pathway analyses indicated the involvement of YAP signaling. EC-specific deletion of YAP limited platelet activation and arterial thrombosis in hyperglycemic mice, whereas EC-specific overexpression of YAP in mice mimicked the prothrombotic state of diabetes, without affecting hemostasis. Mechanistically, we found that hyperglycemia/high glucose-induced endothelial YAP nuclear translocation and subsequently transcriptional expression of COX-2 and mPGES-1 contributed to the elevation of PGE2 and platelet activation. Blockade of EP3 (prostaglandin E receptor 3) activation by oral administration of DG-041 reversed the hyperactivity of platelets and delayed thrombus formation in both EC-specific YAP-overexpressing and hyperglycemic mice. CONCLUSIONS: Collectively, our data suggest that hyperglycemia-induced endothelial YAP activation aggravates platelet activation and arterial thrombus formation via PGE2/EP3 signaling. Targeting EP3 with DG-041 might be therapeutic for diabetes-related thrombosis.
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Diabetes Mellitus , Hiperglucemia , Trombosis , Animales , Humanos , Ratones , Plaquetas/metabolismo , Ciclooxigenasa 2/metabolismo , Diabetes Mellitus/metabolismo , Dinoprostona/metabolismo , Hiperglucemia/complicaciones , Hiperglucemia/metabolismo , Ratones Obesos , Trombosis/genética , Trombosis/metabolismoRESUMEN
Purpose: Expressing opinions and ideas in the workplace is an important aspect of organizational development and employee well-being. However, employee voice intention, which refers to an employee's willingness to share their opinions or ideas, is an area that has received limited attention in research. Therefore, the aim of this study was to develop and validate a reliable measurement tool for employee voice intention. Methods: The study followed a three-stage process. First, in-depth interviews were conducted with managers and employees from Chinese companies, resulting in 38 qualitative data points. Second, the employee voice intention scale was developed and validated through two surveys. Exploratory factor analysis (N=264) and confirmatory factor analysis (N=260) were performed, respectively. Third, the predictive validity of the scale was assessed by collecting 366 valid responses across three rounds of questionnaires, using voice efficacy and employee voice behavior as correlational calibration criteria. Results: The study employed grounded theory methodology to analyze the qualitative data collected, resulting in the development of a robust conceptual framework of employee voice intention. This framework is composed of two dimensions: perceived desirability and perceived feasibility, which together capture the key factors that influence whether an employee will express their opinions or ideas within an organizational context. A corresponding measurement scale was developed, consisting of nine measurement items that underwent rigorous testing to ensure their reliability and validity. Furthermore, the results of the empirical study showed that employee voice intention mediated the positive effect of voice efficacy on voice behavior, supporting the scale's predictive validity. Conclusion: This study provides valuable insights into the dimensions of employee voice intention and contributes significantly to the existing literature on this topic by introducing a reliable and valid measurement tool. Furthermore, it advances our understanding of the underlying dimensions associated with this construct.
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Transfer regression is a practical and challenging problem with important applications in various domains, such as engineering design and localization. Capturing the relatedness of different domains is the key of adaptive knowledge transfer. In this paper, we investigate an effective way of explicitly modelling domain relatedness through transfer kernel, a transfer-specified kernel that considers domain information in the covariance calculation. Specifically, we first give the formal definition of transfer kernel, and introduce three basic general forms that well cover existing related works. To cope with the limitations of the basic forms in handling complex real-world data, we further propose two advanced forms. Corresponding instantiations of the two forms are developed, namely Trkαß and Trkω based on multiple kernel learning and neural networks, respectively. For each instantiation, we present a condition with which the positive semi-definiteness is guaranteed and a semantic meaning is interpreted to the learned domain relatedness. Moreover, the condition can be easily used in the learning of TrGP αß and TrGP ω that are the Gaussian process models with the transfer kernels Trkαß and Trkω respectively. Extensive empirical studies show the effectiveness of TrGP αß and TrGP ω on domain relatedness modelling and transfer adaptiveness.
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Deep neural networks, such as the deep-FSMN, have been widely studied for keyword spotting (KWS) applications while suffering expensive computation and storage. Therefore, network compression technologies such as binarization are studied to deploy KWS models on edge. In this article, we present a strong yet efficient binary neural network for KWS, namely, BiFSMNv2, pushing it to the real-network accuracy performance. First, we present a dual-scale thinnable 1-bit-architecture (DTA) to recover the representation capability of the binarized computation units by dual-scale activation binarization and liberate the speedup potential from an overall architecture perspective. Second, we also construct a frequency-independent distillation (FID) scheme for KWS binarization-aware training, which distills the high-and low-frequency components independently to mitigate the information mismatch between full-precision and binarized representations. Moreover, we propose the learning propagation binarizer (LPB), a general and efficient binarizer that enables the forward and backward propagation of binary KWS networks to be continuously improved through learning. We implement and deploy BiFSMNv2 on ARMv8 real-world hardware with a novel fast bitwise computation kernel (FBCK), which is proposed to fully use registers and increase instruction throughput. Comprehensive experiments show our BiFSMNv2 outperforms the existing binary networks for KWS by convincing margins across different datasets and achieves comparable accuracy with the full-precision networks (only a tiny 1.51% drop on Speech Commands V1-12). We highlight that benefiting from the compact architecture and optimized hardware kernel, BiFSMNv2 can achieve an impressive 25.1 × speedup and 20.2 × storage-saving on edge hardware.
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Existing graph contrastive learning methods rely on augmentation techniques based on random perturbations (e.g., randomly adding or dropping edges and nodes). Nevertheless, altering certain edges or nodes can unexpectedly change the graph characteristics, and choosing the optimal perturbing ratio for each dataset requires onerous manual tuning. In this paper, we introduce Implicit Graph Contrastive Learning (iGCL), which utilizes augmentations in the latent space learned from a Variational Graph Auto-Encoder by reconstructing graph topological structure. Importantly, instead of explicitly sampling augmentations from latent distributions, we further propose an upper bound for the expected contrastive loss to improve the efficiency of our learning algorithm. Thus, graph semantics can be preserved within the augmentations in an intelligent way without arbitrary manual design or prior human knowledge. Experimental results on both graph-level and node-level show that the proposed method achieves state-of-the-art accuracy on downstream classification tasks compared to other graph contrastive baselines, where ablation studies in the end demonstrate the effectiveness of modules in iGCL.
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Algoritmos , Inteligencia , Humanos , Conocimiento , SemánticaRESUMEN
Multi-source transfer regression is a practical and challenging problem where capturing the diverse relatedness of different domains is the key of adaptive knowledge transfer. In this article, we propose an effective way of explicitly modeling the domain relatedness of each domain pair through transfer kernel learning. Specifically, we first discuss the advantages and disadvantages of existing transfer kernels in handling the multi-source transfer regression problem. To cope with the limitations of the existing transfer kernels, we further propose a novel multi-source transfer kernel kms. The proposed kms assigns a learnable parametric coefficient to model the relatedness of each inter-domain pair, and simultaneously regulates the relatedness of the intra-domain pair to be 1. Moreover, to capture the heterogeneous data characteristics of multiple domains, kms exploits different standard kernels for different domain pairs. We further provide a theorem that not only guarantees the positive semi-definiteness of kms but also conveys a semantic interpretation to the learned domain relatedness. Moreover, the theorem can be easily used in the learning of the corresponding transfer Gaussian process model with kms. Extensive empirical studies show the effectiveness of our proposed method on domain relatedness modelling and transfer performance.
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PURPOSE: This study aimed to determine the effect of pentoxifylline (PTX) on the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome pathway and its role in preventing arteriovenous fistula (AVF) failure. METHODS: Vein samples were collected from AVF failure patients and from patients who underwent surgical AVF as a control. The expressions of CD34 and NLRP3 in AVF tissues were detected by immunohistochemistry and Western blotting. Arteriovenous fistula rat models were established by the end-to-end anastomosis of the common carotid artery and external jugular vein. The AVF models were divided into the following groups: AVF, AVF + PTX, AVF + uraemia and AVF + uraemia + PTX. Six weeks after surgery, the AVF tissues in each group were collected to detect the expressions of CD34, NLRP3, caspase-1 and interleukin (IL)-1ß by immunohistochemistry, Western blotting and real-time polymerase chain reaction. RESULTS: The expressions of NLRP3 and CD34 in human AVF failure tissues were significantly higher than those in normal veins (p < 0.001), indicating that NLRP3 was upregulated in patients with AVF failure. In our animal study, the veins in the AVF + uraemia group exhibited heavy hyperplasia, and the boundary between the media and the adventitia was not clear. However, PTX alleviated this hyperplasia. Compared with the AVF models, the AVF + uraemia models had much higher expressions of NLRP3, caspase-1, IL-1ß and CD34 (p < 0.001). However, PTX had the opposite effect against uraemia on the NLRP3 inflammasome pathway at both the gene and protein levels. CONCLUSIONS: Our findings provide new insights that show that PTX can decrease the activity of the NLRP3 inflammasome pathway in AVF models. Pentoxifylline has the potential as a drug for preventing intimal hyperplasia and AVF failure.
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Purpose: Some scholars have explored the connotation and structural elements of employee zhengchong behaviour based on Taiwan's local enterprises, providing results with reference significance. However, there is a lack of accurate measurement scales. How to treat employee zhengchong behaviour (striving for a favour) and effectively deconstruct it is very important to the sustainable development of family firms. Methods: Semistructured interviews were conducted with 62 employees of private enterprises, and the structural dimension of employee zhengchong behaviour was explored with the help of grounded theory. The researchers designed two questionnaires, collected 278 and 331 valid questionnaires in the two surveys, compiled the corresponding measurement scale, and tested it. Results: Employee zhengchong behaviour under differential leadership was a multidimensional structure with rich connotations consisting of four dimensions: showing abilities, collaborating and sharing, excluding outsiders, and ingratiating upwards. The scale includes 16 items. Conclusion: This study enriches the relevant theories while providing a decision reference for family firm leaders to guide employee zhengchong behaviour to reasonably improve firm performance.
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Accumulating evidence has implicated that berberine (BBR) has a beneficial effect on diabetic kidney disease (DKD), but its mechanism is not clear. The aim of this study was to assess whether berberine could alleviate tubulointerstitial fibrosis and attenuate epithelial-to-mesenchymal transition (EMT) and its possible molecular mechanism. High-fat diet (HFD) followed by injection of STZ was used to induce diabetic rats in vivo. After the onset of diabetes, rats were treated with either BBR or saline for 12 weeks. In vitro, the human renal proximal tubular epithelial cell line (HK-2) was exposed to high glucose, with or without BBR. The influence of berberine on renal tubulointerstitial histological changes, markers of epithelial-to-mesenchymal transition (EMT) and (NOD-like receptor pyrin domain-containing protein 3) NLRP3 inflammasome expression were examined. Results showed that in vivo, BBR could significantly ameliorate microalbumin and renal pathologic changes in diabetic rats. Immunofluorescence showed that BBR could inhibit EMT. Furthermore, BBR could down-regulate the level of the NLRP3 inflammasome in diabetic rats. Consistently, in vitro, BBR suppressed high glucose-induced EMT and activation of NLRP3 inflammasome in HK-2. Our study demonstrated that BBR could inhibit high glucose-induced EMT and renal interstitial fibrosis by suppressing the NLRP3 inflammasome. BBR might be used as a novel drug to ameliorate tubulointerstitial fibrosis in DKD.
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Berberina , Diabetes Mellitus Experimental , Nefropatías Diabéticas , Animales , Berberina/farmacología , Berberina/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/prevención & control , Fibrosis , Glucosa , Inflamasomas/metabolismo , Inflamasomas/uso terapéutico , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , RatasRESUMEN
The messenger RNA (mRNA) 3' untranslated regions (3' UTRs), as cis-regulated elements bound by microRNAs (miRNAs), affect their gene translation. However, the role of the trans-regulation of 3' UTRs during heart dysfunction remains elusive. Compared with administration of angiogenic factor with G-patch and forkhead-associate domains 1 (Aggf1), ectopic expression of Aggf1 with its 3' UTR significantly suppressed cardiac dysfunction in angiotensin II-infused mice, with upregulated expression of both Aggf1 and myeloid cell leukemia 1 (Mcl1). Along their 3' UTRs, Mcl1 and Aggf1 mRNAs share binding sites for the same miRNAs, including miR-105, miR-101, and miR-93. We demonstrated that the protein-coding Mcl1 and Aggf1 mRNAs communicate and co-regulate each other's expression through competition for these three miRNAs that target both transcripts via their 3' UTRs. Our results indicate that Aggf1 3' UTR, as a trans-regulatory element, accelerates the cardioprotective role of Aggf1 in response to hypertensive conditions by elevating Mcl1 expression. Our work broadens the scope of gene therapy targets and provides a new insight into gene therapy strategies involving 3' UTRs.
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Proteínas Angiogénicas/genética , Angiotensina II/efectos adversos , Vectores Genéticos/administración & dosificación , Cardiopatías/prevención & control , MicroARNs/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Miocitos Cardíacos/citología , Regiones no Traducidas 3' , Proteínas Angiogénicas/metabolismo , Animales , Células Cultivadas , Dependovirus/genética , Modelos Animales de Enfermedad , Terapia Genética , Células HEK293 , Cardiopatías/inducido químicamente , Cardiopatías/fisiopatología , Pruebas de Función Cardíaca , Humanos , Masculino , Ratones , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismoRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Although angiotensin II (AngII) is known to cause renal injury and fibrosis, the underlying mechanisms remain poorly characterized. Here we show that hypertensive nephropathy (HN) patients and AngII-infused mice exhibit elevated levels of circulating miR103a-3p. We observe a positive correlation between miR-103a-3p levels and AngII-induced renal dysfunction. miR-103a-3p suppresses expression of the sucrose non-fermentable-related serine/threonine-protein kinase SNRK in glomerular endothelial cells, and glomeruli of HN patients and AngII-infused mice show reduced endothelial expression of SNRK. We find that SNRK exerts anti-inflammatory effects by interacting with activated nuclear factor-κB (NF-κB)/p65. Overall, we demonstrate that AngII increases circulating miR-103a-3p levels, which reduces SNRK levels in glomerular endothelial cells, resulting in the over-activation of NF-κB/p65 and, consequently, renal inflammation and fibrosis. Together, our work identifies miR-103a-3p/SNRK/NF-κB/p65 as a regulatory axis of AngII-induced renal inflammation and fibrosis.
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Angiotensina II/metabolismo , Glomerulonefritis/patología , Hipertensión Renal/patología , Glomérulos Renales/patología , MicroARNs/metabolismo , Nefritis/patología , Proteínas Serina-Treonina Quinasas/genética , Adulto , Angiotensina II/administración & dosificación , Animales , Estudios de Casos y Controles , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Fibrosis , Glomerulonefritis/sangre , Glomerulonefritis/genética , Glomerulonefritis/orina , Voluntarios Sanos , Humanos , Hipertensión Renal/sangre , Hipertensión Renal/genética , Hipertensión Renal/orina , Glomérulos Renales/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/sangre , MicroARNs/orina , Persona de Mediana Edad , Nefritis/sangre , Nefritis/genética , Nefritis/orina , Cultivo Primario de Células , Proteínas Serina-Treonina Quinasas/metabolismo , Factor de Transcripción ReIA/metabolismoRESUMEN
BACKGROUND/AIMS: In clinical settings, the pulsatility index (PI) has become a widely used tool for monitoring obstetrics or other vascular diseases. It is based on the maximum Doppler shift waveform derived from ultrasonography. However, it remains unclear whether the PI levels are correctly predicted from the perfusion in mouse model of hindlimb ischemia. METHODS: To explore the relationship between PI and perfusion, we generated a unilateral hindlimb ischemia model in 8-week-old C57BL/6 male mice by ligation of the right common iliac artery and femoral artery. These mice were monitored with laser Doppler perfusion imaging (LDPI) and an ultrasound system (Vevo2100). Vessel densities in ischemic skeletal muscles were measured with vWF staining, which functions as a marker for endothelial cells. In order to further verify PI evaluation in other conditions, we performed therapeutic experiments using hindlimb ischemic mouse with PBS or FGF2 treatment. RESULTS: In the mouse model of hindlimb ischemia, the PI levels were continuously elevated and were accompanied by an increased ratio of perfusion to blood flow. 1 and 4 weeks after ischemia, the densities of vWF staining were correlated with PI values. Moreover, the PI index exactly reflected the perfusion in hindlimb ischemic mice after FGF2 treatment, while it indicated the condition of angiogenesis after therapeutic treatment based on the association between PI values and the number of vWF-positive stained cells in muscles. CONCLUSION: This study confirms the utility of a noninvasive and reproducible ultrasound index for a rapid evaluation of perfusion and blood recovery after hindlimb ischemia in vivo. PI, as one stable and comparable parameter, is correlated with angiogenesis in hindlimb ischemic mouse. Moreover, PI can exactly reflect perfusion and angiogenesis in therapeutic hindlimb ischemic mouse models. This study suggested that PI can serve as a novel index for relatively reproducible and repeatable blood flow recovery in the evaluation of emerging ischemic therapies and disease development in mouse models of hindlimb ischemia.
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Miembro Posterior/patología , Isquemia/patología , Músculo Esquelético/metabolismo , Animales , Modelos Animales de Enfermedad , Factor 2 de Crecimiento de Fibroblastos/farmacología , Miembro Posterior/irrigación sanguínea , Isquemia/metabolismo , Flujometría por Láser-Doppler , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/efectos de los fármacos , Neovascularización Patológica/fisiopatologíaRESUMEN
OBJECTIVE: SNRK (sucrose nonfermenting 1-related kinase) is a novel member of the AMPK (adenosine monophosphate-activated protein kinase)-related superfamily that is activated in the process of angiogenesis. Currently, little is known about the function of SNRK in angiogenesis in the physiological and pathological conditions. APPROACH AND RESULTS: In this study, in Snrk global heterozygous knockout mice, retina angiogenesis and neovessel formation after hindlimb ischemia were suppressed. Consistently, mice with endothelial cell (EC)-specific Snrk deletion exhibited impaired retina angiogenesis, and delayed perfusion recovery and exacerbated muscle apoptosis in ischemic hindlimbs, compared with those of littermate wide-type mice. Endothelial SNRK expression was increased in the extremity vessel samples from nonischemic human. In ECs cultured in hypoxic conditions, HIF1α (hypoxia inducible factor 1α) bound to the SNRK promoter to upregulate SNRK expression. In the nuclei of hypoxic ECs, SNRK complexed with SP1 (specificity protein 1), and together, they bound to an SP1-binding motif in the ITGB1 (ß1 integrin) promoter, resulting in enhanced ITGB1 expression and promoted EC migration. Furthermore, SNRK or SP1 deficiency in ECs ameliorated hypoxia-induced ITGB1 expression and, consequently, inhibited EC migration and angiogenesis. CONCLUSIONS: Taken together, our data have revealed that SNRK/SP1-ITGB1 signaling axis promotes angiogenesis in vivo.
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Células Endoteliales/enzimología , Isquemia/enzimología , Pulmón/irrigación sanguínea , Músculo Esquelético/irrigación sanguínea , Neovascularización Fisiológica , Proteínas Serina-Treonina Quinasas/metabolismo , Vasos Retinianos/enzimología , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Apoptosis , Velocidad del Flujo Sanguíneo , Cadherinas/genética , Cadherinas/metabolismo , Movimiento Celular , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Células Endoteliales/patología , Regulación Enzimológica de la Expresión Génica , Miembro Posterior , Células Endoteliales de la Vena Umbilical Humana/enzimología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Isquemia/genética , Isquemia/fisiopatología , Ratones Endogámicos C57BL , Ratones Noqueados , Regiones Promotoras Genéticas , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/genética , Flujo Sanguíneo Regional , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp1/metabolismoRESUMEN
BACKGROUND/AIMS: The renal resistive index (RI) is a novel candidate as a renal injury prognostic indicator, but it remains unclear how renal RI levels correspond to renal injury in diabetic nephropathy. METHODS: To examine this issue, we compared 8-week-old male C57BL/6 mice fed with high-fat diet (HFD) versus chow diet (CHD) for 16 weeks. At 8 and 12 weeks, the glomerular filtration rate (GFR), urinary albumin-to-creatinine ratio (UACR), and inflammatory factors (IL-1ß, IL-6, TNFα, and MCP-1) were measured, along with the increase in renal RI. RESULTS: Our study suggests RI values positively correlate with GFR for the first 12 weeks of HFD feeding. In contrast, the GFR of 16-week HFD feeding is lower than that of 12-week HFD feeding, whereas RI levels are significantly increased. Additionally, our study suggests RI values accurately indicate the renal fibrosis and renal injury in HFD-fed mice treated with lovastatin. CONCLUSION: This study seems to confirm the utility of a noninvasive and repeatable ultrasound parameter to rapidly evaluate renal fibrosis in a HFD-induced type 2 diabetic mouse model in vivo. This highly sensitive and comparable renal RI measurement could monitor the whole procedure of disease development in real-time. RI measurement of the renal artery is capable of differentiating responses to standard therapy with lovastatin in HFD-fed mice from the CHD group.
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Nefropatías Diabéticas/diagnóstico , Dieta Alta en Grasa , Riñón/diagnóstico por imagen , Ultrasonografía/métodos , Animales , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/fisiopatología , Fibrosis , Tasa de Filtración Glomerular , Riñón/lesiones , Lovastatina/farmacología , Lovastatina/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Arteria Renal/fisiopatologíaRESUMEN
The transient receptor potential melastatin 2 (TRPM2) channel, a Ca2+ permeable channel activated by cAMP, is expressed on pancreatic ß-cells and is responsible for the regulation of insulin secretion. It is known that glucose-stimulated insulin secretion (GSIS) can be potentiated by glucagon like peptide-1 (GLP-1), and that the changes in the extracellular glucose concentration alter the levels of intracellular adenosine ATP and cAMP. The present study hypothesized that TRPM2 mediates the modulatory effect of GLP-1 on insulin secretion. The results demonstrated that silencing of TRPM2 eliminated GLP-1-enhanced insulin secretion, indicating the involvement of TRPM2 in this process. In addition, the results of current recordings of TRPM2 and measurement of the resulting insulin secretion in ß-cells in the presence of GLP-1 and various concentrations of glucose suggest that GLP-1 regulates GSIS via the TRPM2 channel. Furthermore, inhibiting the activity or expression of TRPM2 attenuated GLP-1-induced GSIS. By using specific activators or inhibitors, the present study demonstrated that the two primary downstream effectors of the GLP-1 receptor, exchange protein directly activated by cAMP and protein kinase A, differentially influence GSIS and GLP-1-potentiated GSIS. In conclusion, the present study revealed the role of TRPM2 in GLP-1-regulated insulin secretion. The results of the present study provide a novel avenue for the prevention and treatment of diabetes and its complications.
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BACKGROUND: FUN14 domain containing 1 (FUNDC1) is a highly conserved outer mitochondrial membrane protein. The aim of this study is to examine whether FUNDC1 modulates the mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs), mitochondrial morphology, and function in cardiomyocytes and intact hearts. METHODS: The impacts of FUNDC1 on MAMs formation and cardiac functions were studied in mouse neonatal cardiomyocytes, in mice with cardiomyocyte-specific Fundc1 gene knockout (Fundc1f/Y/CreαMyHC+/- ), and in the cardiac tissues of the patients with heart failure. RESULTS: In mouse neonatal cardiomyocytes and intact hearts, FUNDC1 was localized in MAMs by binding to ER-resided inositol 1,4,5-trisphosphate type 2 receptor (IP3R2). Fundc1 ablation disrupted MAMs and reduced the levels of IP3R2 and Ca2+ in both mitochondria and cytosol, whereas overexpression of Fundc1 increased the levels of IP3R2 and Ca2+ in both mitochondria and cytosol. Consistently, Fundc1 ablation increased Ca2+ levels in ER, whereas Fundc1 overexpression lowered ER Ca2+ levels. Further, Fundc1 ablation in cardiomyocytes elongated mitochondria and compromised mitochondrial functions. Mechanistically, we found that Fundc1 ablation-induced reduction of intracellular Ca2+ levels suppressed mitochondrial fission 1 protein (Fis1) expression and mitochondrial fission by reducing the binding of the cAMP response element binding protein (CREB) in the Fis1 promoter. Fundc1f/Y/CreαMyHC+/- mice but not their littermate control mice (Fundc1wt/Y/CreαMyHC+/- ) exhibited cardiac dysfunction. The ligation of the left ventricle artery of Fundc1f/Y/CreαMyHC+/- mice caused more severe cardiac dysfunction than those in sham-treated Fundc1f/Y/CreαMyHC+/- mice. Finally, we found that the FUNDC1/MAMs/CREB/Fis1 signaling axis was significantly suppressed in patients with heart failure. CONCLUSIONS: We conclude that FUNDC1 binds to IP3R2 to modulate ER Ca2+ release into mitochondria and cytosol. Further, a disruption of the FUNDC1 and IP3R2 interaction lowers the levels of Ca2+ in mitochondria and cytosol, both of which instigate aberrant mitochondrial fission, mitochondrial dysfunction, cardiac dysfunction, and heart failure.
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Retículo Endoplásmico/metabolismo , Insuficiencia Cardíaca/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Mitocondrias Cardíacas/metabolismo , Dinámicas Mitocondriales , Membranas Mitocondriales/metabolismo , Proteínas Mitocondriales/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Sitios de Unión , Calcio/metabolismo , Estudios de Casos y Controles , Células Cultivadas , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Retículo Endoplásmico/patología , Predisposición Genética a la Enfermedad , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Humanos , Membranas Intracelulares/patología , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Ratones Noqueados , Mitocondrias Cardíacas/patología , Membranas Mitocondriales/patología , Proteínas Mitocondriales/deficiencia , Proteínas Mitocondriales/genética , Mitofagia , Miocitos Cardíacos/patología , Fenotipo , Regiones Promotoras Genéticas , Unión Proteica , Transducción de Señal , Factores de TiempoRESUMEN
Statins may decrease chronic kidney diseases (CKDs) risk, but their underlying molecular mechanisms are not completely understood. Recent studies indicate Endothelial-to-mesenchymal transition (EndMT) plays an important role contributing to renal interstitial fibrosis. In the present study, we first investigated whether lovastatin could ameliorate renal fibrosis via suppression of EndMT and its possible mechanism. In vitro experiments, lovastatin significantly ameliorated microalbuminuria and pathologic changes in diabetic rats. Double labeling immunofluorescence showed lovastatin could inhibit EndMT in glomeruli. Furthermore, lovastatin could inhibit oxidative stress and down-regulate TGF-ß1-Smad signaling. Consistent alterations were observed in vivo that lovastatin substantially suppressed EndMT and TGF-ß1 signaling induced by high glucose in glomerular endothelial cells (GEnCs). These data indicated that lovastatin could ameliorate EndMT in glomeruli in diabetic nephropathy, the mechanism of which might be at least partly through suppression of oxidative stress and TGF-ß1/Smad signaling pathway.
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Abnormal angiogenesis plays an important role in impaired wound healing and development of chronic wounds in diabetes mellitus. Angelica dahurica radix is a common traditional Chinese medicine with wide spectrum medicinal effects. In this study, we analyzed the potential roles of Angelica dahurica ethanolic extract (ADEE) in correcting impaired angiogenesis and delayed wound healing in diabetes by using streptozotocin-induced diabetic rats. ADEE treatment accelerated diabetic wound healing through inducing angiogenesis and granulation tissue formation. The angiogenic property of ADEE was subsequently verified ex vivo using aortic ring assays. Furthermore, we investigated the in vitro angiogenic activity of ADEE and its underlying mechanisms using human umbilical vein endothelial cells. ADEE treatment induced HUVECs proliferation, migration, and tube formation, which are typical phenomena of angiogenesis, in dose-dependent manners. These effects were associated with activation of angiogenic signal modulators, including extracellular signal-regulated kinase 1/2 (ERK1/2), Akt, endothelial nitric oxide synthase (eNOS) as well as increased NO production, and independent of affecting VEGF expression. ADEE-induced angiogenic events were inhibited by the MEK inhibitor PD98059, the PI3K inhibitor Wortmannin, and the eNOS inhibitor L-NAME. Our findings highlight an angiogenic role of ADEE and its ability to protect against impaired wound healing, which may be developed as a promising therapy for impaired angiogenesis and delayed wound healing in diabetes.
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Angelica/metabolismo , Diabetes Mellitus Experimental/patología , Neovascularización Fisiológica/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Androstadienos/farmacología , Animales , Aorta/metabolismo , Línea Celular , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Flavonoides/farmacología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Medicina Tradicional China , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo III/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo III/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Estreptozocina , WortmaninaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Triptolide is a most important active ingredient extracted from traditional Chinese medicine Tripterygium, which has been widely used to treat glomerulonephritis as well as immune-mediated disorders, likely for its immunosuppressive, anti-proliferative and anti-inflammatory effects. AIM OF THE STUDY: In this study, we have investigated the potential protective effects of triptolide against diabetic cardiomyopathy (DCM) by regulating immune system, attenuating inflammatory response, thus resulting in decreased cardiac fibrosis and improved left ventricle function. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into 5 groups: normal group, diabetic group and diabetic rats treated with triptolide (50, 100, or 200µg/kg/day resp) for 8 weeks. Cardiac function was performed by echocardiography and histopathology of the hearts was examined with HE, Masson staining and scanning electron microscopy. Immune regulation mediator, macrophage infiltration, inflammatory response and cardiac fibrosis related cytokines were measured by RT-PCR, Western blot and Immunohistochemistry staining. RESULTS: In the diabetic group, the expressions of TLR4 and NF-κB p65 were both up-regulated, which was associated with increased pro-inflammatory cytokines, coupled with cardiac fibrosis and impaired left ventricular function. Interestingly, pathological structure and function of left ventricle were both significantly improved in the triptolide treated groups. Furthermore, the immune mediator TLR4, downstream activator NF-κB p65, macrophage infiltration (CD68+), pro-inflammatory cytokines (TNF-α, IL-1ß), cell adhesion molecule (VCAM-1) and chemokine (MCP-1) were significantly suppressed when treated with medium and high dosage triptolide compared with the diabetic group. Moreover, cardiac fibrosis pathway including α-SMA, TGF-ß1, vimentin and collagen accumulations were observed significantly decreased in the triptolide treated groups. CONCLUSIONS: Our data demonstrated that the protective effects of triptolide against DCM might attribute to inhibition of TLR4-induced NF-κB/IL-1ß immune pathway, suppression of NF-κB/TNF-α/VCAM-1 inflammatory pathway and down-regulation of TGF-ß1/α-SMA/Vimentin fibrosis pathway.