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1.
Mol Med Rep ; 23(6)2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33899122

RESUMO

As a common factor of both type 2 diabetes mellitus (T2DM) and acute coronary syndrome (ACS), circulating microparticles (MPs) may provide a link between these two diseases. The present study compared the content and function of MPs from patients with ACS with or without T2DM. MPs from healthy subjects (n=20), patients with ACS (n=24), patients with T2DM (n=20) and patients with combined ACS and T2DM (n=24) were obtained. After incubating rat thoracic tissue with MPs, the effect of MPs on endothelial­dependent vasodilatation, expression of caveolin­1 and endothelial nitric oxide synthase (eNOS), phosphorylation of eNOS at the S1177 and T495 sites and its association with heat shock protein 90 (Hsp90), and the generation of NO and superoxide anion (O2˙­) were determined. MP concentrations were higher in patients with T2DM and patients with ACS with or without T2DM than in healthy subjects. Moreover, MPs from patients with T2DM or ACS led to impairment in endothelial­dependent vasodilatation, decreased expression of NO, as well as eNOS and its phosphorylation at Ser1177 and association with Hsp90, but increased eNOS phosphorylation at T495, caveolin­1 expression and O2˙­ generation. These effects were strengthened by MPs from patients with ACS combined with T2DM. T2DM not only increased MP content but also resulted in greater vascular impairment effects in ACS. These results may provide novel insight into the treatment of patients with ACS and T2DM.


Assuntos
Síndrome Coronariana Aguda/sangue , Micropartículas Derivadas de Células/metabolismo , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/patologia , Adulto , Animais , Caveolina 1/metabolismo , Células Cultivadas , Diabetes Mellitus Tipo 2/patologia , Angiopatias Diabéticas/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Vasodilatação
2.
Nat Commun ; 12(1): 931, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568658

RESUMO

Caveolae are spherically shaped nanodomains of the plasma membrane, generated by cooperative assembly of caveolin and cavin proteins. Cavins are cytosolic peripheral membrane proteins with negatively charged intrinsically disordered regions that flank positively charged α-helical regions. Here, we show that the three disordered domains of Cavin1 are essential for caveola formation and dynamic trafficking of caveolae. Electrostatic interactions between disordered regions and α-helical regions promote liquid-liquid phase separation behaviour of Cavin1 in vitro, assembly of Cavin1 oligomers in solution, generation of membrane curvature, association with caveolin-1, and Cavin1 recruitment to caveolae in cells. Removal of the first disordered region causes irreversible gel formation in vitro and results in aberrant caveola trafficking through the endosomal system. We propose a model for caveola assembly whereby fuzzy electrostatic interactions between Cavin1 and caveolin-1 proteins, combined with membrane lipid interactions, are required to generate membrane curvature and a metastable caveola coat.


Assuntos
Cavéolas/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Animais , Cavéolas/química , Caveolina 1/genética , Caveolina 1/metabolismo , Membrana Celular/química , Membrana Celular/genética , Membrana Celular/metabolismo , Proteínas de Membrana/genética , Camundongos , Domínios Proteicos , Proteínas de Ligação a RNA/genética , Eletricidade Estática
3.
J Biosci Bioeng ; 131(4): 341-347, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33423964

RESUMO

Burn injury is one of the most common physical injuries in clinic. It is a big challenge to find an ideal treatment for burn injury. Mesenchymal stem cells (MSCs) have been suggested as a promising candidate for wound healing. However, it is critical to improve the therapeutic efficiency of MSCs for treatment of burn injury. Here, we demonstrated that overexpression of caveolin-1, the main component of the caveolae plasma membranes, promoted the proliferation of MSCs both in vitro and in vivo. Moreover, transplantation of MSCs overexpressing caveolin-1 facilitated the expression of various growth factors and immunoregulatory cytokines and accelerated deep second-degree burn wound healing in a rat model of burn injury. Our results suggest that overexpression of caveolin-1 can improve the therapeutic efficiency of MSCs, which may be a promising strategy for the treatment of deep second-degree burn injury in clinic.


Assuntos
Queimaduras/metabolismo , Caveolina 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Cicatrização , Animais , Queimaduras/terapia , Caveolina 1/genética , Masculino , Transplante de Células-Tronco Mesenquimais , Ratos , Ratos Wistar , Pele/metabolismo
4.
Biochem J ; 478(1): 247-260, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33346337

RESUMO

The integrity of the intestinal mucosal barrier protects hosts against pathological conditions. Early mucosal restitution after wounding refers to epithelial cell migration into a defect. The RNA-binding protein HuR plays an important role in the posttranscriptional regulation of gene expression and is involved in many aspects of cellular physiology. In the present study, we investigated the role of HuR in the regulation of cell migration through the posttranscriptional regulation of Caveolin-1 (Cav-1). Online software was used to identify Cav-1 mRNA as a potential target of HuR. The interaction of HuR with Cav-1 mRNA was investigated via ribonucleoprotein immunoprecipitation (RNP IP) assays and biotin pulldown analysis. HuR was found to bind specifically to the Cav-1 3'-UTR rather than the coding region or 5'-UTR. Transfection of cells with siHuR decreased both HuR protein levels and Cav-1 protein levels; conversely, ectopic overexpression of HuR via infection of cells with an adenoviral vector containing HuR cDNA (AdHuR) increased Cav-1 protein levels without disturbing Cav-1 mRNA levels. Thus, HuR enhanced Cav-1 expression in vitro by stimulating Cav-1 translation. Intestinal epithelium-specific HuR knockout in mice decreased Cav-1 protein levels without changing Cav-1 mRNA levels, consistent with the in vitro results. Decreasing the levels of HuR via siHuR transfection inhibited early epithelial repair, but this effect was reversed by ectopic overexpression of GFP-tagged Cav-1. These results indicate that posttranscriptional regulation of Cav-1 gene expression by HuR plays a critical role in the regulation of rapid epithelial repair after wounding.


Assuntos
Caveolina 1/metabolismo , Proteína Semelhante a ELAV 1/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas , Animais , Caveolina 1/genética , Movimento Celular , Proteína Semelhante a ELAV 1/genética , Feminino , Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Biossíntese de Proteínas/genética , Estabilidade de RNA/genética , RNA Interferente Pequeno , Proteínas de Ligação a RNA/genética , Ratos
5.
Phytomedicine ; 80: 153377, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33126167

RESUMO

BACKGROUND: Osteoporosis is a threat to aged people who have excessive osteoclast activation and bone resorption, subsequently causing fracture and even disability. Inhibiting osteoclast differentiation and absorptive functions has become an efficient approach to treat osteoporosis, but osteoclast-targeting inhibitors available clinically remain rare. Kirenol (Kir), a bioactive diterpenoid derived from an antirheumatic Chinese herbal medicine Herba Siegesbeckiae, can treat collagen-induced arthritis in vivo and promote osteoblast differentiation in vitro, while the effects of Kir on osteoclasts are still unclear. PURPOSE: We explore the role of Kir on RANKL-induced osteoclastogenesis in vitro and bone loss in vivo. METHODS: The in vitro effects of Kir on osteoclast differentiation, bone resorption and the underlying mechanisms were evaluated with bone marrow-derived macrophages (BMMs). In vivo experiments were performed using an ovariectomy (OVX)-induced osteoporosis model. RESULTS: We found that Kir remarkably inhibited osteoclast generation and bone resorption in vitro. Mechanistically, Kir significantly inhibited F-actinring formation and repressed RANKL-induced NF-κB p65 activation and p-p38, p-ERK and c-Fos expression. Moreover, Kir inhibited both the expression and nuclear translocation of NFATc1. Ca2+ oscillation and caveolin-1 (Cav-1) were also reduced by Kir during osteoclastogenesis in vitro. Consistent with these findings, 2-10 mg/kg Kir attenuated OVX-induced osteoporosis in vivo as evidenced by decreased osteoclast numbers and downregulated Cav-1 and NFATc1 expression. CONCLUSIONS: Kir suppresses osteoclastogenesis and the Cav-1/NFATc1 signaling pathway both in vitro and in vivo and protects against OVX-induced osteoporosis. Our findings reveal Kir as a potential safe oral treatment for osteoporosis.


Assuntos
Caveolina 1/metabolismo , Diterpenos/farmacologia , Fatores de Transcrição NFATC/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/prevenção & controle , Administração Oral , Animais , Reabsorção Óssea/prevenção & controle , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diterpenos/administração & dosagem , Feminino , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Osteoclastos/efeitos dos fármacos , Osteoporose/etiologia , Ovariectomia/efeitos adversos , Ligante RANK/metabolismo , Ligante RANK/farmacologia , Transdução de Sinais/efeitos dos fármacos
6.
Nat Commun ; 11(1): 4279, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855410

RESUMO

Plasma and tumor caveolin-1 (Cav-1) are linked with disease progression in prostate cancer. Here we report that metabolomic profiling of longitudinal plasmas from a prospective cohort of 491 active surveillance (AS) participants indicates prominent elevations in plasma sphingolipids in AS progressors that, together with plasma Cav-1, yield a prognostic signature for disease progression. Mechanistic studies of the underlying tumor supportive onco-metabolism reveal coordinated activities through which Cav-1 enables rewiring of cancer cell lipid metabolism towards a program of 1) exogenous sphingolipid scavenging independent of cholesterol, 2) increased cancer cell catabolism of sphingomyelins to ceramide derivatives and 3) altered ceramide metabolism that results in increased glycosphingolipid synthesis and efflux of Cav-1-sphingolipid particles containing mitochondrial proteins and lipids. We also demonstrate, using a prostate cancer syngeneic RM-9 mouse model and established cell lines, that this Cav-1-sphingolipid program evidences a metabolic vulnerability that is targetable to induce lethal mitophagy as an anti-tumor therapy.


Assuntos
Caveolina 1/metabolismo , Neoplasias da Próstata/metabolismo , Esfingolipídeos/metabolismo , Idoso , Animais , Caveolina 1/sangue , Caveolina 1/genética , Linhagem Celular Tumoral , Ceramidas/metabolismo , Intervalo Livre de Doença , Regulação Neoplásica da Expressão Gênica , Glicoesfingolipídeos/biossíntese , Humanos , Lipídeos/sangue , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Pirrolidinas/farmacologia , Esfingomielinas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Biol Regul Homeost Agents ; 34(2): 457-465, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32475100

RESUMO

The aim of this study was to explore the effects of Caveolin-1 on lung injury in rats with chronic obstructive pulmonary disease (COPD). The forced expiratory volume in 0.3 s/forced vital capacity (FEV0.3/ FVC) and peak expiratory flow (PEF) were determined. The total white blood cells (WBC), neutrophil ratio (NEUT%), mononuclear macrophage ratio (MNM%), lymphocyte ratio (LY%) and protein concentration in bronchoalveolar lavage fluid (BALF) were measured. Both FEV0.3/FVC and PEF significantly declined in the COPD group compared with those in the Control group, while they significantly rose in the IWR-1 group and Daidzin group compared with those in the COPD group. HE staining showed that there were alveolar dilatation and enlargement with obviously increased intercept in the COPD group, while there were basically no changes in the alveoli in the IWR-1 group and Daidzin group. Massive apoptosis of alveolar tissues was observed in COPD group, and there was only a little apoptosis in IWR-1 group and Daidzin group. In COPD group, WBC, NEUT% and protein concentration in BALF were obviously increased, MNM% was obviously decreased, and there was no obvious difference in LY% compared with those in the Control group. In the the IWR-1 group and Daidzin group, WBC, NEUT%, protein concentration, MNM% and LY% in BALF had no obvious differences compared with those in the Control group. In the IWR-1 group and Daidzin group, WBC, NEUT% and protein concentration evidently declined, MNM% evidently rose, and there was no obvious difference in LY% compared with those in the COPD group. Caveolin-1, Wnt-1 and ß-catenin in lung tissues were remarkably higher in the COPD group than those in the Control group. Caveolin-1 was remarkably higher in the IWR-1 group than that in the Control group. And Wnt-1 and ß-catenin were higher in the Daidzin group than those in the Control group. In addition, Wnt-1 and ß-catenin in lung tissues markedly declined in the IWR-1 group compared with those in the COPD group. Caveolin-1, Wnt-1 and ß-catenin in lung tissues also markedly declined in the Daidzin group compared with those in the COPD group. Caveolin-1 can improve lung injury in COPD rats through the Wnt/ß-catenin signaling pathway.


Assuntos
Caveolina 1/metabolismo , Lesão Pulmonar/terapia , Doença Pulmonar Obstrutiva Crônica/terapia , Via de Sinalização Wnt , Animais , Imidas/uso terapêutico , Isoflavonas/uso terapêutico , Pulmão , Quinolinas/uso terapêutico , Ratos
8.
Cell Mol Biol (Noisy-le-grand) ; 66(3): 221-229, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32538775

RESUMO

It can be misleading to think that the new severe acute respiratory syndrome coronavirus (SARS-CoV2) which has a very strong mutation and adaptation capabilities, uses only the angiotensin-converting enzyme II (ACE2) pathway to reach target cells. Despite all the precautions taken, the pandemic attack continues and the rapid increase in the number of deaths suggest that this virus has entered the cell through different pathways and caused damage through different mechanisms. The main reason why the ACE2 pathway comes to the fore in all scientific studies is that this receptor is located at the entry point of basic mechanisms that provide alveolo-capillary homeostasis. SARS-CoV-2 has to use nuclear factor-κB (NF-kB), caveloae, clathrin, lipoxin, serine protease and proteasome pathways in addition to ACE2 to enter the target cell and initiate damage. For this reason, while new drug development studies are continuing, in order to be beneficial to patients in their acute period, it is imperative that we are able to come up with drugs that activate or inhibit these pathways and are currently in clinical use. It is also critical that we adopt these new pathways to the treatment of pregnant women affected by SARS-CoV-2, based on the scientific data we use to treat the general population.


Assuntos
Betacoronavirus/metabolismo , Caveolina 1/metabolismo , Infecções por Coronavirus/metabolismo , Lipoxinas/metabolismo , NF-kappa B/metabolismo , Pneumonia Viral/metabolismo , Complicações Infecciosas na Gravidez/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anticolesterolemiantes/uso terapêutico , Sítios de Ligação , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Descoberta de Drogas/métodos , Reposicionamento de Medicamentos/métodos , Feminino , Humanos , Transmissão Vertical de Doença Infecciosa/prevenção & controle , NF-kappa B/antagonistas & inibidores , Uso Off-Label , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Inibidores de Proteassoma/uso terapêutico , Serina Endopeptidases/metabolismo , Inibidores de Serino Proteinase/uso terapêutico , Internalização do Vírus
9.
PLoS One ; 15(6): e0235116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569321

RESUMO

Here, we examine known GTPase regulators of vesicle trafficking events to assess whether they affect endothelial cell (EC) lumen and tube formation. We identify novel roles for the small GTPases Rab3A, Rab3B, Rab8A, Rab11A, Rab27A, RalA, RalB and caveolin-1 in co-regulating membrane trafficking events that control EC lumen and tube formation. siRNA suppression of individual GTPases such as Rab3A, Rab8A, and RalB markedly inhibit tubulogenesis, while greater blockade is observed with combinations of siRNAs such as Rab3A and Rab3B, Rab8A and Rab11A, and RalA and RalB. These combinations of siRNAs also disrupt very early events in lumen formation including the formation of intracellular vacuoles. In contrast, knockdown of the endocytosis regulator, Rab5A, fails to inhibit EC tube formation. Confocal microscopy and real-time videos reveal that caveolin-1 strongly labels intracellular vacuoles and localizes to the EC apical surface as they fuse to form the luminal membrane. In contrast, Cdc42 and Rab11A localize to a perinuclear, subapical region where intracellular vacuoles accumulate and fuse during lumen formation. Our new data demonstrates that EC tubulogenesis is coordinated by a series of small GTPases to control polarized membrane trafficking events to generate, deliver, and fuse caveolin-1-labeled vacuoles to create the apical membrane surface.


Assuntos
Caveolina 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Vacúolos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Membrana Celular/metabolismo , Colágeno/metabolismo , Exocitose , Proteínas de Fluorescência Verde/metabolismo , Humanos , Modelos Biológicos , Transporte Proteico , RNA Interferente Pequeno/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas ral de Ligação ao GTP/metabolismo , Quinases da Família src/metabolismo
10.
Ann Vasc Surg ; 69: 391-399, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599107

RESUMO

BACKGROUND: Phosphodiesterase enzymes play a pivotal role in the pathogenesis of ischemia/reperfusion (IR). We examined the role of milrinone (MIL), a phosphodiesterase 3 inhibitor, on remote injury of the heart and lung after abdominal aortic cross-clamping. DESIGN: Experimental study. METHODS: Twenty-one Wistar rats were divided into 3 groups: (1) control (C, n = 7), underwent laparotomy and exploration of abdominal aorta only; (2) IR (n = 7), normal saline was applied intraperitoneally (i.p) before IR induced by clamping of the abdominal aorta for 1 hr and then allowing reperfusion for 1 hr; and (3) MIL + IR (n = 7), MIL was given (0.5 mg/kg, i.p) before IR. After sacrification, the lungs and hearts were taken out for analyses and the tissue malondialdehyde (MDA) and glutathione (GSH) were studied. All tissues were examined under light microscopy and transmission electron microscopy (TEM). Expressions of caveolin (Cav)-1 in the lung and Cav-1 and Cav-3 in the heart were examined immunohistochemically. RESULTS: The MIL + IR group had significantly a lower magnitude of oxidative stress than the IR group both in the lung and heart (lung: P = 0.03 for MDA and 0.001 for GSH and heart: P = 0.002 for MDA and 0.000 for GSH). In light microscopy, the MIL + IR group had statistically a lower total injury score than the IR group for both the lung and heart tissue (P = 0.03 and P = 0.04, respectively). In TEM, regression of mitochondrial degeneration and lamellar bodies in type II pneumocytes in the lungs and obvious improvements in disruption at the intercalated discs and mitochondrial degeneration in the hearts in the MIL + IR group were detected compared with the IR group. The expression of both Cav-1 and Cav-3 in the MIL + IR group was improved compared with the IR group (P = 0.03 for both). CONCLUSIONS: MIL attenuates remote injury of heart and lung in lower body IR by inhibiting oxidative stress. Moreover, Cav-1 and Cav-3 might have a potential role in MIL-induced cardioprotection.


Assuntos
Aorta Abdominal/cirurgia , Coração/efeitos dos fármacos , Lesão Pulmonar/prevenção & controle , Pulmão/efeitos dos fármacos , Milrinona/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Inibidores da Fosfodiesterase 3/farmacologia , Animais , Antioxidantes/farmacologia , Caveolina 1/metabolismo , Caveolina 3/metabolismo , Constrição , Modelos Animais de Doenças , Pulmão/metabolismo , Pulmão/ultraestrutura , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Transdução de Sinais
11.
Nat Commun ; 11(1): 2988, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532976

RESUMO

Tissue homeostasis requires regulation of cell-cell communication, which relies on signaling molecules and cell contacts. In skin epidermis, keratinocytes secrete factors transduced by melanocytes into signaling cues promoting their pigmentation and dendrite outgrowth, while melanocytes transfer melanin pigments to keratinocytes to convey skin photoprotection. How epidermal cells integrate these functions remains poorly characterized. Here, we show that caveolae are asymmetrically distributed in melanocytes and particularly abundant at the melanocyte-keratinocyte interface in epidermis. Caveolae in melanocytes are modulated by ultraviolet radiations and keratinocytes-released factors, like miRNAs. Preventing caveolae formation in melanocytes increases melanin pigment synthesis through upregulation of cAMP signaling and decreases cell protrusions, cell-cell contacts, pigment transfer and epidermis pigmentation. Altogether, we identify that caveolae serve as molecular hubs that couple signaling outputs from keratinocytes to mechanical plasticity of pigment cells. The coordination of intercellular communication and contacts by caveolae is thus crucial to skin pigmentation and tissue homeostasis.


Assuntos
Cavéolas/metabolismo , Queratinócitos/metabolismo , Melanócitos/metabolismo , Pigmentação da Pele/fisiologia , Pele/metabolismo , Caveolina 1/metabolismo , Comunicação Celular/fisiologia , Comunicação Celular/efeitos da radiação , Células Cultivadas , Técnicas de Cocultura , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Epiderme/ultraestrutura , Células HeLa , Humanos , Queratinócitos/citologia , Melanócitos/citologia , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação , Pele/citologia , Pele/ultraestrutura , Raios Ultravioleta
12.
Invest Ophthalmol Vis Sci ; 61(5): 33, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32428234

RESUMO

Purpose: This study aimed to investigate the role and pathophysiological mechanism of ATP binding cassette transporter A1 (ABCA1) in regulating the IOP and aqueous humor outflow. Methods: ABCA1 expression was measured in trabecular meshwork samples obtained from patients with POAG and human donor eyes by Western blot. To further evaluate the functional significance of ABCA1, porcine angular aqueous plexus (AAP) cells, which are equivalent to human Schlemm's canal endothelial cells, were either treated with ABCA1 agonist GW3965 or transduced with lentivirus expressing ABCA1-shRNA. Transendothelial electrical resistance, protein expression, and nitric oxide (NO) concentration were measured. GW3965 was administered by intracameral injection. IOP and aqueous humor outflow facility were also measured. Results: ABCA1 expression was significantly higher in the trabecular meshwork tissue of patients with POAG compared with controls. ABCA1 upregulation in angular aqueous plexus cells decreased the transendothelial electrical resistance in the angular aqueous plexus monolayers accompanied by a 0.56-fold decrease in caveolin-1 expression and a 2.85-fold and 1.17-fold increase in endothelial NO synthase expression and NO concentration, respectively (n = 3, P < 0.05). Conversely, ABCA1 downregulation increased transendothelial electrical resistance and caveolin-1 expression and decreased endothelial NO synthase expression and NO production (n = 3, P < 0.05). GW3965 decreased IOP and significantly increased conventional outflow facility (P < 0.05). Conclusions: Regulation of aqueous humor outflow via the caveolin-1/endothelial NO synthase/NO pathway is a newly defined function of ABCA1 that is different from its traditional role in mediating cholesterol efflux. ABCA1 is a compelling, novel therapeutic candidate for the treatment of glaucoma and ocular hypertension.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/fisiologia , Caveolina 1/metabolismo , Glaucoma de Ângulo Aberto/metabolismo , Pressão Intraocular/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia , Animais , Humor Aquoso/fisiologia , Benzoatos/farmacologia , Benzilaminas/farmacologia , Western Blotting , Impedância Elétrica , Células Endoteliais/efeitos dos fármacos , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Lentivirus/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Suínos , Malha Trabecular/metabolismo , Trabeculectomia , Transfecção
13.
PLoS One ; 15(5): e0232235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401768

RESUMO

OBJECTIVE: Altered expression of caveolin-1 (CAV1) and autophagy marker ATG4C is observed in various types of human cancers. However, the clinical significance of CAV1 and ATG4C expression in epithelial ovarian cancer (EOC) remains largely unknown. The present study aims to explore the clinicopathological value and prognostic significance of CAV1 and ATG4C expression in EOC. METHODS: The expression pattern and prognostic value of CAV1 and ATG4C mRNA in EOC were analyzed using data from the Cancer Genome Atlas (TCGA) database (N = 373). In addition, immunohistochemistry analysis was performed to detect and assay the expression of CAV1 and ATG4C proteins in tissue microarray of EOC. RESULTS: Based on TCGA data, Kaplan-Meier analysis indicated that patients with low CAV1 mRNA (p = 0.021) and high ATG4C mRNA (p = 0.018) expression had a significantly shorter overall survival (OS). Cox regression analysis demonstrated that the expression levels of CAV1 (p = 0.023) and ATG4C mRNA (p = 0.040) were independent prognostic factors for OS in EOC. In addition, the Concordance Index of the nomogram for OS prediction was 0.660. Immunohistochemical analysis showed the expression levels of stromal CAV1 and cancerous ATG4C proteins, and high expression of both CAV1 and ATG4C protein in the stroma were found to significantly correlate with the histologic subtypes of EOC, especially with serous subtype. CONCLUSIONS: Decreased expression of CAV1 mRNA and increased expression of ATG4C mRNA in EOC can predict poor overall survival. The expression levels of CAV1 protein in stromal cells and ATG4C protein in cancer cells are significantly associated with histologic subtypes of EOC. These findings suggest that CAV1 and ATG4C serve as useful prognostic biomarkers and candidate therapeutic targets in EOC.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/patologia , Caveolina 1/metabolismo , Cisteína Endopeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Epitelial do Ovário/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Prognóstico , Análise de Sobrevida , Adulto Jovem
14.
PLoS One ; 15(5): e0233854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470006

RESUMO

Alpha-toxin (Hla) is a major virulence factor of Staphylococcus aureus (S. aureus) and plays an important role in S. aureus-induced pneumonia. It binds as a monomer to the cell surface of eukaryotic host cells and forms heptameric transmembrane pores. Sensitivities toward the toxin of various types of potential host cells have been shown to vary substantially, and the reasons for these differences are unclear. We used three human model airway epithelial cell lines (16HBE14o-, S9, A549) to correlate cell sensitivity (measured as rate of paracellular gap formation in the cell layers) with Hla monomer binding, presence of the potential Hla receptors ADAM10 or α5ß1 integrin, presence of the toxin-stabilizing factor caveolin-1 as well as plasma membrane lipid composition (phosphatidylserine/choline, sphingomyelin). The abundance of ADAM10 correlated best with gap formation or cell sensitivities, respectively, when the three cell types were compared. Caveolin-1 or α5ß1 integrin did not correlate with toxin sensitivity. The relative abundance of sphingomyelin in plasma membranes may also be used as a proxi for cellular sensitivity against alpha-toxin as sphingomyelin abundances correlated well with the intensities of alpha-toxin mediated gap formation in the cell layers.


Assuntos
Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/toxicidade , Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidade , Interações Hospedeiro-Patógeno , Sistema Respiratório/patologia , Células A549 , Caveolina 1/metabolismo , Membrana Celular/efeitos dos fármacos , Tamanho Celular , Células Epiteliais/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Modelos Biológicos , Fosfolipídeos/metabolismo , Ligação Proteica , Receptores de Superfície Celular/metabolismo
16.
Oxid Med Cell Longev ; 2020: 9761539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082483

RESUMO

It is estimated that in 2017 there were 451 million people with diabetes worldwide. These figures are expected to increase to 693 million by 2045; thus, innovative preventative programs and treatments are a necessity to fight this escalating pandemic disorder. Caveolin-1 (CAV1), an integral membrane protein, is the principal component of caveolae in membranes and is involved in multiple cellular functions such as endocytosis, cholesterol homeostasis, signal transduction, and mechanoprotection. Previous studies demonstrated that CAV1 is critical for insulin receptor-mediated signaling, insulin secretion, and potentially the development of insulin resistance. Here, we summarize the recent progress on the role of CAV1 in diabetes and diabetic complications.


Assuntos
Cavéolas/metabolismo , Caveolina 1/metabolismo , Complicações do Diabetes/etiologia , Diabetes Mellitus/etiologia , Resistência à Insulina/genética , Insulina/metabolismo , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Caveolina 1/genética , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Humanos , Inflamação/etiologia , Inflamação/genética , Inflamação/metabolismo , Obesidade/etiologia , Obesidade/genética , Obesidade/metabolismo , Estresse Oxidativo/genética , Transdução de Sinais
17.
Biochem Soc Trans ; 48(1): 155-163, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32049332

RESUMO

Caveolae are small Ω-shaped invaginations of the plasma membrane that play important roles in mechanosensing, lipid homeostasis and signaling. Their typical morphology is characterized by a membrane funnel connecting a spherical bulb to the membrane. Membrane funnels (commonly known as necks and pores) are frequently observed as transient states during fusion and fission of membrane vesicles in cells. However, caveolae display atypical dynamics where the membrane funnel can be stabilized over an extended period of time, resulting in cell surface constrained caveolae. In addition, caveolae are also known to undergo flattening as well as short-range cycles of fission and fusion with the membrane, requiring that the membrane funnel closes or opens up, respectively. This mini-review considers the transition between these different states and highlights the role of the protein and lipid components that have been identified to control the balance between surface association and release of caveolae.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Transporte/metabolismo , Cavéolas/metabolismo , Caveolina 1/metabolismo , Filaminas/metabolismo , Lipídeos de Membrana/metabolismo , Animais , Proteínas de Transporte/genética , Células HeLa , Humanos , Camundongos , Camundongos Knockout , Transdução de Sinais
18.
Biochim Biophys Acta Mol Cell Res ; 1867(5): 118676, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32044386

RESUMO

In egress routes of malignancy, cancer cells are constantly subjected to shear stress imposed by blood/lymph flow. Increasing evidence points toward the regulatory roles of shear stress in tumor cell adhesion and motility. Although it is known that integrin endocytic trafficking governs focal adhesion (FA) turnover and cell migration, the effect and biological consequences of low shear stress (LSS) on integrin trafficking remain unclear. Here, we identified the critical role of integrin ß1 trafficking and caveolin-1 (Cav-1) mediated endocytosis in LSS-induced cell directional migration. LSS altered the distribution of integrin ß1 in MDA-MB-231 cells and significantly promoted its internalization and recycling, which in turn facilitated FA turnover and directional cell migration. Furthermore, LSS induced cytoskeleton remodeling, which was required for internalization of integrin ß1. LSS down-regulated the acetylation level of microtubules (MTs) via activating ROCK/HDAC6 pathway, resulting in elevation of MTs dynamics, Cav-1 motility, and Cav-1-dependent integrin ß1 recycling. We also showed that high HDAC6 expression was a ROCK-dependent prognostic factor, which was correlated with poor outcomes in breast cancer patients. Taken together, these results defined a novel mechanism by which LSS enhanced integrin ß1 trafficking via actin cytoskeleton remodeling and ROCK/HDAC6 mediated deacetylation of MTs, thereby promoting FAs turnover and directional cell migration.


Assuntos
Neoplasias da Mama/metabolismo , Desacetilase 6 de Histona/metabolismo , Integrina beta1/metabolismo , Microtúbulos/metabolismo , Quinases Associadas a rho/metabolismo , Acetilação , Caveolina 1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Adesões Focais/metabolismo , Humanos , Transporte Proteico , Estresse Mecânico
19.
FASEB J ; 34(3): 4653-4669, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32017270

RESUMO

Transmissible gastroenteritis virus (TGEV) is a swine enteropathogenic coronavirus that causes significant economic losses in swine industry. Current studies on TGEV internalization mainly focus on viral receptors, but the internalization mechanism is still unclear. In this study, we used single-virus tracking to obtain the detailed insights into the dynamic events of the TGEV internalization and depict the whole sequential process. We observed that TGEVs could be internalized through clathrin- and caveolae-mediated endocytosis, and the internalization of TGEVs was almost completed within ~2 minutes after TGEVs attached to the cell membrane. Furthermore, the interactions of TGEVs with actin and dynamin 2 in real time during the TGEV internalization were visualized. To our knowledge, this is the first report that single-virus tracking technique is used to visualize the entire dynamic process of the TGEV internalization: before the TGEV internalization, with the assistance of actin, clathrin, and caveolin 1 would gather around the virus to form the vesicle containing the TGEV, and after ~60 seconds, dynamin 2 would be recruited to promote membrane fission. These results demonstrate that TGEVs enter ST cells via clathrin- and caveolae-mediated endocytic, actin-dependent, and dynamin 2-dependent pathways.


Assuntos
Gastroenterite Suína Transmissível/metabolismo , Gastroenterite Suína Transmissível/virologia , Vírus da Gastroenterite Transmissível/patogenicidade , Actinas/metabolismo , Animais , Cavéolas/metabolismo , Caveolina 1/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Membrana Celular/virologia , Clatrina/metabolismo , Dinamina II/metabolismo , Endocitose/fisiologia , Fusão de Membrana/fisiologia , Suínos , Internalização do Vírus
20.
Exp Cell Res ; 389(2): 111897, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035951

RESUMO

Mucins are major macromolecular components of lung mucus that are mainly responsible for the viscoelastic property of mucus. MUC5AC is a major mucin glycoprotein that is hypersecreted in asthmatic individuals. Vascular endothelial growth factor (VEGF) has been implicated in inflammatory and airway blood vessel remodeling in asthmatics. Our previous studies indicate that VEGF upregulates MUC5AC expression by interacting with VEGF receptor 2 (VEGFR2). It has been shown that dexamethasone (Dex) downregulates MUC5AC expression; however, the underlying mechanisms have not been completely elucidated. Therefore, we sought to investigate the effect of Dex on MUC5AC expression induced by VEGF and study the underlying mechanisms. We tested the effects of Dex on VEGFR2 and RhoA activation, caveolin-1 expression, and the association of caveolin-1 and VEGFR2 in primary bronchial epithelial cells. Dex downregulated MUC5AC mRNA and protein levels in a dose- and time-dependent manner, and suppressed the activation of VEGFR2 and RhoA induced by VEGF. Additionally, Dex upregulated caveolin-1 protein levels in a dose- and time-dependent manner. Furthermore, phospho-VEGFR2 expression was decreased through overexpression of caveolin-1 and increased after caveolin-1 knockdown. Dex treatment attenuated the VEGF-decreased association of caveolin-1 and VEGFR2. Collectively, our findings suggest that Dex downregulates VEGF-induced MUC5AC expression by inactivating VEGFR2 and RhoA. Furthermore, decreased MUC5AC expression by Dex was related to the increased association of caveolin-1 with VEGFR2. Further studies characterizing these mechanisms are required to facilitate the development of improved treatment strategies for asthma.


Assuntos
Asma/patologia , Brônquios/metabolismo , Dexametasona/farmacologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Mucina-5AC/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Asma/metabolismo , Brônquios/citologia , Brônquios/efeitos dos fármacos , Caveolina 1/genética , Caveolina 1/metabolismo , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Glucocorticoides/farmacologia , Humanos , Mucina-5AC/genética , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
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