RESUMO
A link between increased glycolysis and vascular calcification has recently been reported, but it remains unclear how increased glycolysis contributes to vascular calcification. We therefore investigated the role of PFKFB3, a critical enzyme of glycolysis, in vascular calcification. We found that PFKFB3 expression was upregulated in calcified mouse VSMCs and arteries. We showed that expression of miR-26a-5p and miR-26b-5p in calcified mouse arteries was significantly decreased, and a negative correlation between Pfkfb3 mRNA expression and miR-26a-5p or miR-26b-5p was seen in these samples. Overexpression of miR-26a/b-5p significantly inhibited PFKFB3 expression in VSMCs. Intriguingly, pharmacological inhibition of PFKFB3 using PFK15 or knockdown of PFKFB3 ameliorated vascular calcification in vD3 -overloaded mice in vivo or attenuated high phosphate (Pi)-induced VSMC calcification in vitro. Consistently, knockdown of PFKFB3 significantly reduced glycolysis and osteogenic transdifferentiation of VSMCs, whereas overexpression of PFKFB3 in VSMCs induced the opposite effects. RNA-seq analysis and subsequent experiments revealed that silencing of PFKFB3 inhibited FoxO3 expression in VSMCs. Silencing of FoxO3 phenocopied the effects of PFKFB3 depletion on Ocn and Opg expression but not Alpl in VSMCs. Pyruvate or lactate supplementation, the product of glycolysis, reversed the PFKFB3 depletion-mediated effects on ALP activity and OPG protein expression in VSMCs. Our results reveal that blockade of PFKFB3-mediated glycolysis inhibits vascular calcification in vitro and in vivo. Mechanistically, we show that FoxO3 and lactate production are involved in PFKFB3-driven osteogenic transdifferentiation of VSMCs. PFKFB3 may be a promising therapeutic target for the treatment of vascular calcification.
Assuntos
Proteína Forkhead Box O3 , MicroRNAs , Fosfofrutoquinase-2 , Calcificação Vascular , Animais , Camundongos , Glicólise , Ácido Láctico , Músculo Liso Vascular , Monoéster Fosfórico Hidrolases , Calcificação Vascular/genética , Fosfofrutoquinase-2/metabolismo , Proteína Forkhead Box O3/metabolismoRESUMO
ENPP1 is well known for its role in regulating skeletal and soft tissue mineralization. It primarily exerts its function through the generation of pyrophosphate, a key inhibitor of hydroxyapatite formation. Several previous studies have suggested that ENPP1 also contributes to a range of human diseases including diabetes, cancer, cardiovascular disease, and osteoarthritis. In this review, we summarize the pathological roles of ENPP1 in mineralization and these soft tissue disorders. We also discuss the underlying mechanisms through which ENPP1 exerts its pathological effects. A fuller understanding of the pathways through which ENPP1 acts may help to develop novel therapeutic strategies for these commonly diagnosed morbidities.
Assuntos
Neoplasias/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/metabolismo , Animais , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus/metabolismo , Humanos , Osteoartrite/metabolismoRESUMO
Recent genome-wide association and transcriptome-wide association studies have identified an association between the PALMD locus, encoding palmdelphin, a protein involved in myoblast differentiation, and calcific aortic valve disease (CAVD). Nevertheless, the function and underlying mechanisms of PALMD in CAVD remain unclear. We herein investigated whether and how PALMD affects the pathogenesis of CAVD using clinical samples from CAVD patients and a human valve interstitial cell (hVIC) in vitro calcification model. We showed that PALMD was upregulated in calcified regions of human aortic valves and calcified hVICs. Furthermore, silencing of PALMD reduced hVIC in vitro calcification, osteogenic differentiation, and apoptosis, whereas overexpression of PALMD had the opposite effect. RNA-Seq of PALMD-depleted hVICs revealed that silencing of PALMD reduced glycolysis and nuclear factor-κB (NF-κB)-mediated inflammation in hVICs and attenuated tumor necrosis factor α-induced monocyte adhesion to hVICs. Having established the role of PALMD in hVIC glycolysis, we examined whether glycolysis itself could regulate hVIC osteogenic differentiation and inflammation. Intriguingly, the inhibition of PFKFB3-mediated glycolysis significantly attenuated osteogenic differentiation and inflammation of hVICs. However, silencing of PFKFB3 inhibited PALMD-induced hVIC inflammation, but not osteogenic differentiation. Finally, we showed that the overexpression of PALMD enhanced hVIC osteogenic differentiation and inflammation, as opposed to glycolysis, through the activation of NF-κB. The present study demonstrates that the genome-wide association- and transcriptome-wide association-identified CAVD risk gene PALMD may promote CAVD development through regulation of glycolysis and NF-κB-mediated inflammation. We propose that targeting PALMD-mediated glycolysis may represent a novel therapeutic strategy for treating CAVD.
Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Estenose da Valva Aórtica/metabolismo , Calcinose , Células Cultivadas , Estudo de Associação Genômica Ampla , Glicólise , Humanos , Inflamação/metabolismo , Proteínas de Membrana/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , OsteogêneseRESUMO
A highly regiospecific vinylogous carbene insertion protocol for direct asymmetric C-H functionalization of indoles with arylvinyldiazoacetates has been developed. Under the catalysis of simple Rh(I)/chiral diene complexes, the reaction occurs solely at the vinylogous position of the vinylcarbenoid with exceptional E selectivity and enantiocontrol. It provides an efficient way to obtain an interesting class of chiral indole scaffolds bearing an α,ß-unsaturated ester unit and a gem-diaryl carbon stereocenter in good yields (≤99%) with excellent enantioselectivities (≤96%) at room temperature.
Assuntos
Ródio , Estereoisomerismo , Catálise , Indóis , PolienosRESUMO
Tanshinone IIa is a key ingredient extracted from the traditional Chinese medicine Salvia miltiorrhiza (Danshen), and is widely used to treat various cardiovascular diseases. Vascular calcification is a common pathological change of cardiovascular tissues in patients with chronic kidney disease, diabetes, hypertension and atherosclerosis. However, whether Tanshinone IIa inhibits vascular calcification and the underlying mechanisms remain largely unknown. This study aims to investigate whether Tanshinone IIa can inhibit vascular calcification using high phosphate-induced vascular smooth muscle cell and aortic ring calcification model, and high dose vitamin D3 (vD3)-induced mouse models of vascular calcification. Alizarin red staining and calcium quantitative assay showed that Tanshinone IIa significantly inhibited high phosphate-induced vascular smooth muscle cell and aortic ring calcification. qPCR and Western blot showed that Tanshinone IIa attenuated the osteogenic transition of vascular smooth muscle cells. In addition, Tanshinone IIa also significantly inhibited high dose vD3-induced mouse aortic calcification and aortic osteogenic transition. Mechanistically, Tanshinone IIa inhibited the activation of NF-κB and ß-catenin signaling in normal vascular smooth muscle cells. Similar to Tanshinone IIa, inhibition of NF-κB and ß-catenin signaling using the chemical inhibitors SC75741 and LF3 attenuated high phosphate-induced vascular smooth muscle cell calcification. These results suggest that Tanshinone IIa attenuates vascular calcification at least in part through inhibition of NF-κB and ß-catenin signaling, and Tanshinone IIa may be a potential drug for the treatment of vascular calcification.
Assuntos
NF-kappa B , Calcificação Vascular , Animais , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Transdução de Sinais , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/tratamento farmacológico , Calcificação Vascular/metabolismo , Fosfatos/metabolismoRESUMO
A rhodium(I)-diene catalyzed highly enantioselective C(sp2 )-H functionalization of simple unprotected indoles, pyrroles, and their common analogues such as furans, thiophenes, and benzofurans with arylvinyldiazoesters has been developed for the first time. This transformation features unusual site-selectivity exclusively at the vinyl terminus of arylvinylcarbene and enables a reliable and rapid synthetic protocol to access a distinctive class of diarylmethine-bearing α,ß-unsaturated esters containing a one or two heteroarene-attached tertiary carbon stereocenter in high yields and excellent enantioselectivities under mild reaction conditions. Mechanistic studies and DFT calculations suggest that, compared to the aniline substrate, the more electron-rich indole substrate lowers the C-C addition barrier and alters the rate-determining step to the reductive elimination, leading to different isotope effect.
Assuntos
Ródio , Catálise , Indóis , Metano/análogos & derivados , Pirróis , EstereoisomerismoRESUMO
A one-pot rhodium-catalyzed C-H functionalization/organocatalyzed oxa-Michael addition cascade reaction has been developed. This methodology enables the stereodivergent synthesis of diverse 2,3-disubstituted dihydrobenzofurans with broad functional group compatibility in good yields with high levels of stereoselectivity under exceptionally mild conditions. The full complement of stereoisomers of chiral 2,3-disubstituted dihydrobenzofurans and 3,4-disubstituted isochromans could be accessed at will by appropriate permutations of the two chiral catalysts. The current work provides a rare example of two chiral catalysts independently controlling two contiguous stereogenic centers subsequently via a two-step reaction in a single operation.
RESUMO
Asymmetric insertion of an arylvinylcarbenoid into the C-H bond for direct enantioselective C(sp2)-H functionalization of aniline derivatives catalyzed by a rhodium(I)-diene complex was developed for the first time. The reaction occurred exclusively at the uncommon vinyl terminus site with excellent E selectivity and enantioselectivities, providing various chiral γ,γ-gem-diarylsubstituted α,ß-unsaturated esters with broad functional group compatibility under simple and mild conditions. It provides a rare example of the asymmetric C-H insertion of arenes with selective vinylogous reactivity. Synthesis applications of this protocol were featured by several versatile product transformations. Systematic DFT calculations were also performed to elucidate the reaction mechanism and origin of the uncommon enantio- and regioselectivity of the Rh(I)-catalyzed C(sp2)-H functionalization reaction. The measured and computed inverse deuterium kinetic isotope effect supports the C-C bond-formation step as the rate-determining step. Attractive interactions between the chiral ligand and substrates were also proposed to control the enantioselectivity.
RESUMO
Sex differences in cardiovascular disease (CVD), including aortic stenosis, atherosclerosis and cardiovascular calcification, are well documented. High levels of testosterone, the primary male sex hormone, are associated with increased risk of cardiovascular calcification, whilst estrogen, the primary female sex hormone, is considered cardioprotective. Current understanding of sexual dimorphism in cardiovascular calcification is still very limited. This review assesses the evidence that the actions of sex hormones influence the development of cardiovascular calcification. We address the current question of whether sex hormones could play a role in the sexual dimorphism seen in cardiovascular calcification, by discussing potential mechanisms of actions of sex hormones and evidence in pre-clinical research. More advanced investigations and understanding of sex hormones in calcification could provide a better translational outcome for those suffering with cardiovascular calcification.
Assuntos
Androgênios/fisiologia , Estrogênios/fisiologia , Doenças das Valvas Cardíacas/etiologia , Calcificação Vascular/etiologia , Animais , Modelos Animais de Doenças , Doenças das Valvas Cardíacas/metabolismo , Humanos , Transdução de Sinais , Calcificação Vascular/metabolismoRESUMO
Estrogen exerts its cardiovascular protective role at least in part by regulating endothelial hydrogen sulfide (H2S) release, but the underlying mechanisms remain to be fully elucidated. Estrogen exerts genomic effects, i.e. those involving direct binding of the estrogen receptor (ER) to gene promoters in the nucleus, and nongenomic effects, mediated by interactions of the ER with other proteins. Here, using human umbilical vein endothelial cells (HUVECs), immunological detection, MS-based analyses, and cGMP and H2S assays, we show that 17ß-estradiol (E2) rapidly enhances endothelial H2S release in a nongenomic manner. We found that E2 induces phosphorylation of cystathionine γ-lyase (CSE), the key enzyme in vascular endothelial H2S generation. Mechanistically, E2 enhanced the interaction of membrane ERα with the Gα subunit Gαi-2/3, which then transactivated particulate guanylate cyclase-A (pGC-A) to produce cGMP, thereby activating protein kinase G type I (PKG-I). We also found that PKG-Iß, but not PKG-Iα, interacts with CSE, leading to its phosphorylation, and rapidly induces endothelial H2S release. Furthermore, we report that silencing of either CSE or pGC-A in mice attenuates E2-induced aorta vasodilation. These results provide detailed mechanistic insights into estrogen's nongenomic effects on vascular endothelial H2S release and advance our current understanding of the protective activities of estrogen in the cardiovascular system.
Assuntos
Cistationina gama-Liase/metabolismo , Estradiol/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Sulfeto de Hidrogênio/metabolismo , GMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Receptor alfa de Estrogênio/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Genoma Humano , Guanilato Ciclase/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacosRESUMO
BACKGROUND: Neutrophils form the first line of innate host defense against invading microorganisms. We previously showed that F0F1 ATP synthase (F-ATPase), which is widely known as mitochondrial respiratory chain complex V, is expressed in the plasma membrane of human neutrophils and is involved in regulating cell migration. Whether F-ATPase performs cellular functions through other pathways remains unknown. METHODS: Blue native polyacrylamide gel electrophoresis followed by nano-ESI-LC MS/MS identification and bioinformatic analysis were used to identify protein complexes containing F-ATPase. Then, the identified protein complexes containing F-ATPase were verified by immunoblotting, immunofluorescence colocalization, immunoprecipitation, real-time RT-PCR and agarose gel electrophoresis. Immunoblotting, flow cytometry and a LPS-induced mouse lung injury model were used to assess the effects of the F-ATPase-containing protein complex in vitro and in vivo. RESULTS: We found that the voltage-gated calcium channel (VGCC) α2δ-1 subunit is a binding partner of cell surface F-ATPase in human neutrophils. Further investigation found that the physical connection between the two proteins may exist between the F1 part (α and ß subunits) of F-ATPase and the α2 part of VGCC α2δ-1. Real-time RT-PCR and PCR analyses showed that Cav2.3 (R-type) is the primary type of VGCC expressed in human neutrophils. Research on the F-ATPase/Cav2.3 functional complex indicated that it can regulate extracellular Ca2+ influx, thereby modulating ERK1/2 phosphorylation and reactive oxygen species production, which are typical features of neutrophil activation. In addition, the inhibition of F-ATPase can reduce neutrophil accumulation in the lungs of mice that were intratracheally instilled with lipopolysaccharide, suggesting that the inhibition of F-ATPase may prevent neutrophilic inflammation-induced tissue damage. CONCLUSIONS: In this study, we identified a mechanism by which neutrophil activity is modulated, with simultaneous regulation of neutrophil-mediated pulmonary damage. These results show that surface F-ATPase of neutrophils is a potential innate immune therapeutic target.
Assuntos
Canais de Cálcio Tipo R/metabolismo , Cálcio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Espaço Extracelular/metabolismo , Pulmão/metabolismo , Neutrófilos/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Lesão Pulmonar Aguda/complicações , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Adulto , Sequência de Aminoácidos , Animais , Membrana Celular/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Lipopolissacarídeos , Pulmão/patologia , Camundongos , Modelos Biológicos , Ativação de Neutrófilo , Peptídeos/química , Peptídeos/metabolismo , Fosforilação , Pneumonia/complicações , Pneumonia/metabolismo , Pneumonia/patologia , Ligação Proteica , Isoformas de Proteínas/metabolismo , Subunidades Proteicas/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Arterial medial calcification (AMC) is thought to share some outward similarities to skeletal mineralization and has been associated with the transdifferentiation of vascular smooth muscle cells (VSMCs) to an osteoblast-like phenotype. ATP and UTP have previously been shown to inhibit bone mineralization. This investigation compared the effects of extracellular nucleotides on calcification in VSMCs with those seen in osteoblasts. ATP, UTP and the ubiquitous mineralization inhibitor, pyrophosphate (PPi ), dose dependently inhibited VSMC calcification by ≤85%. Culture of VSMCs in calcifying conditions was associated with an increase in apoptosis; treatment with ATP, UTP, and PPi reduced apoptosis to levels seen in non-calcifying cells. Extracellular nucleotides had no effect on osteoblast viability. Basal alkaline phosphatase (TNAP) activity was over 100-fold higher in osteoblasts than VSMCs. ATP and UTP reduced osteoblast TNAP activity (≤50%) but stimulated VSMC TNAP activity (≤88%). The effects of extracellular nucleotides on VSMC calcification, cell viability and TNAP activity were unchanged by deletion or inhibition of the P2Y2 receptor. Conversely, the actions of ATP/UTP on bone mineralization and TNAP activity were attenuated in osteoblasts lacking the P2Y2 receptor. Ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) hydrolyses ATP and UTP to produce PPi . In both VSMCs and osteoblasts, deletion of NPP1 blunted the inhibitory effects of extracellular nucleotides suggesting involvement of P2 receptor independent pathways. Our results show that although the overall functional effect of extracellular nucleotides on AMC and bone mineralization is similar there are clear differences in the cellular mechanisms mediating these actions.
Assuntos
Calcificação Fisiológica , Espaço Extracelular/metabolismo , Nucleotídeos/farmacologia , Túnica Média/patologia , Calcificação Vascular/patologia , Trifosfato de Adenosina/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difosfatos/farmacologia , Camundongos , Modelos Biológicos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Diester Fosfórico Hidrolases/deficiência , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/deficiência , Pirofosfatases/metabolismo , Receptores Purinérgicos P2/metabolismo , Uridina Trifosfato/farmacologiaRESUMO
Patients with end-stage renal disease (ESRD) have elevated circulating calcium (Ca) and phosphate (Pi), and exhibit accelerated progression of calcific aortic valve disease (CAVD). We hypothesized that matrix vesicles (MVs) initiate the calcification process in CAVD. Ca induced rat valve interstitial cells (VICs) calcification at 4.5 mM (16.4-fold; p < 0.05) whereas Pi treatment alone had no effect. Ca (2.7 mM) and Pi (2.5 mM) synergistically induced calcium deposition (10.8-fold; p < 0.001) in VICs. Ca treatment increased the mRNA of the osteogenic markers Msx2, Runx2, and Alpl (p < 0.01). MVs were harvested by ultracentrifugation from VICs cultured with control or calcification media (containing 2.7 mM Ca and 2.5 mM Pi) for 16 hr. Proteomics analysis revealed the marked enrichment of exosomal proteins, including CD9, CD63, LAMP-1, and LAMP-2 and a concomitant up-regulation of the Annexin family of calcium-binding proteins. Of particular note Annexin VI was shown to be enriched in calcifying VIC-derived MVs (51.9-fold; p < 0.05). Through bioinformatic analysis using Ingenuity Pathway Analysis (IPA), the up-regulation of canonical signaling pathways relevant to cardiovascular function were identified in calcifying VIC-derived MVs, including aldosterone, Rho kinase, and metal binding. Further studies using human calcified valve tissue revealed the co-localization of Annexin VI with areas of MVs in the extracellular matrix by transmission electron microscopy (TEM). Together these findings highlight a critical role for VIC-derived MVs in CAVD. Furthermore, we identify calcium as a key driver of aortic valve calcification, which may directly underpin the increased susceptibility of ESRD patients to accelerated development of CAVD.
Assuntos
Anexina A6/metabolismo , Estenose da Valva Aórtica/metabolismo , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Calcinose/metabolismo , Matriz Extracelular/metabolismo , Vesículas Extracelulares/metabolismo , Hipercalcemia/etiologia , Falência Renal Crônica/complicações , Idoso , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Valva Aórtica/ultraestrutura , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/patologia , Calcinose/etiologia , Calcinose/genética , Calcinose/patologia , Cálcio/metabolismo , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Matriz Extracelular/ultraestrutura , Vesículas Extracelulares/ultraestrutura , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Hipercalcemia/diagnóstico , Falência Renal Crônica/diagnóstico , Masculino , Microscopia Eletrônica de Transmissão , Mapas de Interação de Proteínas , Proteômica/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Regulação para CimaRESUMO
The first rhodium(I)-catalyzed enantioselective Si-H insertion reaction of α-diazoesters and α-diazophosphonates has been developed. The use of a C1-symmetric chiral diene ligand enabled the asymmetric reaction to proceed under exceptionally mild conditions and give versatile chiral α-silyl esters and phosphonates with excellent enantioselectivities (up to 99% ee). The mechanism and stereochemical pathway of this novel Rh(I)-carbene-directed Si-H insertion was investigated by deuterium kinetic isotope effect experiments and DFT calculations.
RESUMO
The process of vascular calcification shares many similarities with that of physiological skeletal mineralization, and involves the deposition of hydroxyapatite crystals in arteries. However, the cellular mechanisms responsible have yet to be fully explained. Bone morphogenetic protein (BMP-9) has been shown to exert direct effects on both bone development and vascular function. In the present study, we have investigated the role of BMP-9 in vascular smooth muscle cell (VSMC) calcification. Vessel calcification in chronic kidney disease (CKD) begins pre-dialysis, with factors specific to the dialysis milieu triggering accelerated calcification. Intriguingly, BMP-9 was markedly elevated in serum from CKD children on dialysis. Furthermore, in vitro studies revealed that BMP-9 treatment causes a significant increase in VSMC calcium content, alkaline phosphatase (ALP) activity and mRNA expression of osteogenic markers. BMP-9-induced calcium deposition was significantly reduced following treatment with the ALP inhibitor 2,5-Dimethoxy-N-(quinolin-3-yl) benzenesulfonamide confirming the mediatory role of ALP in this process. The inhibition of ALK1 signalling using a soluble chimeric protein significantly reduced calcium deposition and ALP activity, confirming that BMP-9 is a physiological ALK1 ligand. Signal transduction studies revealed that BMP-9 induced Smad2, Smad3 and Smad1/5/8 phosphorylation. As these Smad proteins directly bind to Smad4 to activate target genes, siRNA studies were subsequently undertaken to examine the functional role of Smad4 in VSMC calcification. Smad4-siRNA transfection induced a significant reduction in ALP activity and calcium deposition. These novel data demonstrate that BMP-9 induces VSMC osteogenic differentiation and calcification via ALK1, Smad and ALP dependent mechanisms. This may identify new potential therapeutic strategies for clinical intervention.
Assuntos
Receptores de Ativinas Tipo I/metabolismo , Calcificação Fisiológica , Diferenciação Celular , Fator 2 de Diferenciação de Crescimento/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Osteoblastos/citologia , Receptores de Activinas Tipo II , Fosfatase Alcalina/metabolismo , Animais , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diálise , Fator 2 de Diferenciação de Crescimento/sangue , Fator 2 de Diferenciação de Crescimento/farmacologia , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Fosfatos/farmacologia , Insuficiência Renal Crônica/sangue , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Bone mineralization is a carefully orchestrated process, regulated by a number of promoters and inhibitors that function to ensure effective hydroxyapatite formation. Here we sought to identify new regulators of this process through a time series microarray analysis of mineralising primary osteoblast cultures over a 27 day culture period. To our knowledge this is the first microarray study investigating murine calvarial osteoblasts cultured under conditions that permit both physiological extracellular matrix mineralization through the formation of discrete nodules and the terminal differentiation of osteoblasts into osteocytes. RT-qPCR was used to validate and expand the microarray findings. We demonstrate the significant up-regulation of >6,000 genes during the osteoblast mineralization process, the highest-ranked differentially expressed genes of which were those dominated by members of the PPAR-γ signalling pathway, namely Adipoq, Cd36 and Fabp4. Furthermore, we show that the inhibition of this signalling pathway promotes matrix mineralisation in these primary osteoblast cultures. We also identify Cilp, Phex, Trb3, Sox11, and Psat1 as novel regulators of matrix mineralization. Further studies examining the precise function of the identified genes and their interactions will advance our understanding of the mechanisms underpinning biomineralization.
Assuntos
Calcificação Fisiológica/fisiologia , Osteoblastos/fisiologia , Animais , Calcificação Fisiológica/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Durapatita/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Osteócitos/metabolismo , Osteócitos/fisiologia , PPAR gama/genética , PPAR gama/metabolismo , Transdução de Sinais , Crânio/metabolismo , Crânio/fisiologia , Transcrição Gênica , Regulação para CimaRESUMO
Vascular calcification is frequently seen in patients with chronic kidney disease (CKD), and significantly increases cardiovascular mortality and morbidity. Sirt7, a NAD+-dependent histone deacetylases, plays a crucial role in cardiovascular disease. However, the role of Sirt7 in vascular calcification remains largely unknown. Using in vitro and in vivo models of vascular calcification, this study showed that Sirt7 expression was significantly reduced in calcified arteries from mice administered with high dose of vitamin D3 (vD3). We found that knockdown or inhibition of Sirt7 promoted vascular smooth muscle cell (VSMC), aortic ring and vascular calcification in mice, whereas overexpression of Sirt7 had opposite effects. Intriguingly, this protective effect of Sirt7 on vascular calcification is dependent on its deacetylase activity. Unexpectedly, Sirt7 did not alter the osteogenic transition of VSMCs. However, our RNA-seq and subsequent studies demonstrated that knockdown of Sirt7 in VSMCs resulted in increased intracellular reactive oxygen species (ROS) accumulation, and induced an Nrf-2 mediated oxidative stress response. Treatment with the ROS inhibitor N-acetylcysteine (NAC) significantly attenuated the inhibitory effect of Sirt7 on VSMC calcification. Furthermore, we found that knockdown of Sirt7 delayed cell cycle progression and accelerated cellular senescence of VSMCs. Taken together, our results indicate that Sirt7 regulates vascular calcification at least in part through modulation of ROS and cellular senescence of VSMCs. Sirt7 may be a potential therapeutic target for vascular calcification.
RESUMO
BACKGROUND: Congenital heart disease (CHD) is a prevalent congenital cardiac malformation, which lacks effective early biological diagnosis and intervention. MicroRNAs, as epigenetic regulators of cardiac development, provide potential biomarkers for the diagnosis and treatment of CHD. However, the mechanisms underlying miRNAs-mediated regulation of cardiac development and CHD malformation remain to be further elucidated. This study aimed to explore the function of microRNA-20b-5p (miR-20b-5p) in cardiac development and CHD pathogenesis. METHODS AND RESULTS: miRNA expression profiling identified that miR-20b-5p was significantly downregulated during a 12-day cardiac differentiation of human embryonic stem cells (hESCs), whereas it was markedly upregulated in plasma samples of atrial septal defect (ASD) patients. Our results further revealed that miR-20b-5p suppressed hESCs-derived cardiac differentiation by targeting tet methylcytosine dioxygenase 2 (TET2) and 5-hydroxymethylcytosine, leading to a reduction in key cardiac transcription factors including GATA4, NKX2.5, TBX5, MYH6 and cTnT. Additionally, knockdown of TET2 significantly inhibited cardiac differentiation, which could be partially restored by miR-20b-5p inhibition. CONCLUSIONS: Collectively, this study provides compelling evidence that miR-20b-5p functions as an inhibitory regulator in hESCs-derived cardiac differentiation by targeting TET2, highlighting its potential as a biomarker for ASD.
Assuntos
Dioxigenases , MicroRNAs , Humanos , Diferenciação Celular , Dioxigenases/genética , DNA/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
Tumor suppressor gene p53 and its aggregate have been found to be involved in many angiogenesis-related pathways. We explored the possible p53 aggregation formation mechanisms commonly occur after ischemic stroke, such as hypoxia and the presence of reactive oxygen species (ROS). The angiogenic pathways involving p53 mainly occur in nucleus or cytoplasm, with one exception that occurs in mitochondria. Considering the high mitochondrial density in brain and endothelial cells, we proposed that the cyclophilin D (CypD)-dependent vascular endothelial cell (VECs) necrosis pathway occurring in the mitochondria is one of the major factors that affects angiogenesis. Hence, targeting p53 aggregation, a key intermediate in the pathway, could be an alternative therapeutic target for post-stroke management.
RESUMO
17ß-estradiol (E2) plays a key role in endometriosis through regulation of angiogenesis. Smad1 has been reported to be up-regulated in patients with endometriosis. However, the role of Smad1 in E2-mediated angiogenesis during the development of endometriosis remains to be determined. This study aimed to explore the role of Smad1 in E2-mediated angiogenesis during endometriosis and its underlying mechanisms. Immunofluorescence staining and Western blotting were performed to examine the expression of p-Smad1 in ectopic and control endometrium. Western blotting was used to examine activation of Smad1 signaling in NMECs, EMECs and HUVECs. Tube formation assay was performed to examine the effect of E2 on angiogenesis. Cell proliferation and migration was determined using in real-time by xCELLigence RTCA DP instrument. We found that the expression of p-Smad1 was significantly up-regulated in ectopic endometrium and ectopic intima microvascular endothelial cells. E2 non-genomically stimulated phosphorylation of Smad1 in HUVECs. c-Src and p44/42 MAPK(ERK1/2) signaling pathways are required for E2's induction on Smad1 phosphorylation. Moreover, caveolae is involved in E2-induced Smad1 phosphorylation in vascular endothelial cells. E2 promoted tube formation of vascular endothelial cells through c-Src/ERK1/2/Smad1 signaling pathway. Knockdown of Smad1 expression attenuated E2-induced proliferation and migration of HUVECs. In conclusion, E2 promotes proliferation, migration and tube formation of HUVECs through c-Src/ERK1/2/Smad1 signaling pathway. Our data shed new lights on the mechanisms through which E2 contributes to endometriosis, and may provide novel strategies to treat endometriosis.