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1.
Nat Immunol ; 21(1): 30-41, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31819254

RESUMO

NLRP3-inflammasome-driven inflammation is involved in the pathogenesis of a variety of diseases. Identification of endogenous inflammasome activators is essential for the development of new anti-inflammatory treatment strategies. Here, we identified that apolipoprotein C3 (ApoC3) activates the NLRP3 inflammasome in human monocytes by inducing an alternative NLRP3 inflammasome via caspase-8 and dimerization of Toll-like receptors 2 and 4. Alternative inflammasome activation in human monocytes is mediated by the Toll-like receptor adapter protein SCIMP. This triggers Lyn/Syk-dependent calcium entry and the production of reactive oxygen species, leading to activation of caspase-8. In humanized mouse models, ApoC3 activated human monocytes in vivo to impede endothelial regeneration and promote kidney injury in an NLRP3- and caspase-8-dependent manner. These data provide new insights into the regulation of the NLRP3 inflammasome and the pathophysiological role of triglyceride-rich lipoproteins containing ApoC3. Targeting ApoC3 might prevent organ damage and provide an anti-inflammatory treatment for vascular and kidney diseases.


Assuntos
Injúria Renal Aguda/imunologia , Apolipoproteína C-III/imunologia , Caspase 8/metabolismo , Nefropatias/imunologia , Monócitos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Injúria Renal Aguda/patologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apolipoproteína C-III/genética , Linhagem Celular , Modelos Animais de Doenças , Células HEK293 , Humanos , Inflamassomos/imunologia , Inflamação/genética , Inflamação/imunologia , Nefropatias/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
3.
Diabetologia ; 67(7): 1368-1385, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38503901

RESUMO

AIMS/HYPOTHESIS: Protein kinase CK2 acts as a negative regulator of insulin expression in pancreatic beta cells. This action is mainly mediated by phosphorylation of the transcription factor pancreatic and duodenal homeobox protein 1 (PDX1). In pancreatic alpha cells, PDX1 acts in a reciprocal fashion on glucagon (GCG) expression. Therefore, we hypothesised that CK2 might positively regulate GCG expression in pancreatic alpha cells. METHODS: We suppressed CK2 kinase activity in αTC1 cells by two pharmacological inhibitors and by the CRISPR/Cas9 technique. Subsequently, we analysed GCG expression and secretion by real-time quantitative RT-PCR, western blot, luciferase assay, ELISA and DNA pull-down assays. We additionally studied paracrine effects on GCG secretion in pseudoislets, isolated murine islets and human islets. In vivo, we examined the effect of CK2 inhibition on blood glucose levels by systemic and alpha cell-specific CK2 inhibition. RESULTS: We found that CK2 downregulation reduces GCG secretion in the murine alpha cell line αTC1 (e.g. from 1094±124 ng/l to 459±110 ng/l) by the use of the CK2-inhibitor SGC-CK2-1. This was due to a marked decrease in Gcg gene expression through alteration of the binding of paired box protein 6 (PAX6) and transcription factor MafB to the Gcg promoter. The analysis of the underlying mechanisms revealed that both transcription factors are displaced by PDX1. Ex vivo experiments in isolated murine islets and pseudoislets further demonstrated that CK2-mediated reduction in GCG secretion was only slightly affected by the higher insulin secretion after CK2 inhibition. The kidney capsule transplantation model showed the significance of CK2 for GCG expression and secretion in vivo. Finally, CK2 downregulation also reduced the GCG secretion in islets isolated from humans. CONCLUSIONS/INTERPRETATION: These novel findings not only indicate an important function of protein kinase CK2 for proper GCG expression but also demonstrate that CK2 may be a promising target for the development of novel glucose-lowering drugs.


Assuntos
Caseína Quinase II , Células Secretoras de Glucagon , Glucagon , Proteínas de Homeodomínio , Caseína Quinase II/metabolismo , Caseína Quinase II/genética , Animais , Glucagon/metabolismo , Camundongos , Humanos , Células Secretoras de Glucagon/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Transativadores/metabolismo , Transativadores/genética , Masculino , Linhagem Celular , Insulina/metabolismo
4.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255932

RESUMO

The treatment of wounds using the body's own resources is a promising approach to support the physiological regenerative process. To advance this concept, we evaluated the effect of nanofat (NF) on wound healing. For this purpose, full-thickness skin defects were created in dorsal skinfold chambers of wild-type mice. These defects were filled with NF generated from the inguinal subcutaneous adipose tissue of green fluorescent protein (GFP)+ donor mice, which was stabilized using platelet-rich plasma (PRP). Empty wounds and wounds solely filled with PRP served as controls. Wound closure, vascularization and formation of granulation tissue were repeatedly analyzed using stereomicroscopy, intravital fluorescence microscopy, histology and immunohistochemistry over an observation period of 14 days. PRP + NF-treated wounds exhibited accelerated vascularization and wound closure when compared to controls. This was primarily due to the fact that the grafted NF contained a substantial fraction of viable GFP+ vascular and lymph vessel fragments, which interconnected with the GFP- vessels of the host tissue. Moreover, the switch from inflammatory M1- to regenerative M2-polarized macrophages was promoted in PRP + NF-treated wounds. These findings indicate that NF markedly accelerates and improves the wound healing process and, thus, represents a promising autologous product for future wound management.


Assuntos
Neovascularização Patológica , Cicatrização , Animais , Camundongos , Pele , Tecido de Granulação , Proteínas de Fluorescência Verde/genética , Microscopia de Fluorescência
5.
Circulation ; 144(11): 893-908, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34192892

RESUMO

BACKGROUND: Cardiovascular diseases and chronic kidney disease (CKD) are highly prevalent, aggravate each other, and account for substantial mortality. Both conditions are characterized by activation of the innate immune system. The alarmin interleukin-1α (IL-1α) is expressed in a variety of cell types promoting (sterile) systemic inflammation. The aim of the present study was to examine the role of IL-1α in mediating inflammation in the setting of acute myocardial infarction (AMI) and CKD. METHODS: We assessed the expression of IL-1α on the surface of monocytes from patients with AMI and patients with CKD and determined its association with atherosclerotic cardiovascular disease events during follow-up in an explorative clinical study. Furthermore, we assessed the inflammatory effects of IL-1α in several organ injury models in Il1a-/- and Il1b-/- mice and investigated the underlying mechanisms in vitro in monocytes and endothelial cells. RESULTS: IL-1α is strongly expressed on the surface of monocytes from patients with AMI and CKD compared with healthy controls. Higher IL-1α surface expression on monocytes from patients with AMI and CKD was associated with a higher risk for atherosclerotic cardiovascular disease events, which underlines the clinical relevance of IL-1α. In mice, IL-1α, but not IL-1ß, mediates leukocyte-endothelial adhesion as determined by intravital microscopy. IL-1α promotes accumulation of macrophages and neutrophils in inflamed tissue in vivo. Furthermore, IL-1α on monocytes stimulates their homing at sites of vascular injury. A variety of stimuli such as free fatty acids or oxalate crystals induce IL-1α surface expression and release by monocytes, which then mediates their adhesion to the endothelium via IL-1 receptor-1. IL-1α also promotes expression of the VCAM-1 (vascular cell adhesion molecule-1) on endothelial cells, thereby fostering the adhesion of circulating leukocytes. IL-1α induces inflammatory injury after experimental AMI, and abrogation of IL-1α prevents the development of CKD in oxalate or adenine-fed mice. CONCLUSIONS: IL-1α represents a key mediator of leukocyte-endothelial adhesion and inflammation in AMI and CKD. Inhibition of IL-1α may serve as a novel anti-inflammatory treatment strategy.


Assuntos
Adesão Celular/fisiologia , Células Endoteliais/metabolismo , Interleucina-1alfa/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Animais , Adesão Celular/efeitos dos fármacos , Endotélio/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-1alfa/farmacologia , Camundongos , Monócitos/metabolismo , Infarto do Miocárdio/metabolismo , Neutrófilos/metabolismo , Insuficiência Renal Crônica/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
6.
Int J Mol Sci ; 24(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36613872

RESUMO

Glucose homeostasis is of critical importance for the survival of organisms. It is under hormonal control and often coordinated by the action of kinases and phosphatases. We have previously shown that CK2 regulates insulin production and secretion in pancreatic ß-cells. In order to shed more light on the CK2-regulated network of glucose homeostasis, in the present study, a qRT-PCR array was carried out with 84 diabetes-associated genes. After inhibition of CK2, fructose-1,6-bisphosphatase 1 (FBP1) showed a significant lower gene expression. Moreover, FBP1 activity was down-regulated. Being a central enzyme of gluconeogenesis, the secretion of glucose was decreased as well. Thus, FBP1 is a new factor in the CK2-regulated network implicated in carbohydrate metabolism control.


Assuntos
Caseína Quinase II , Frutose-Bifosfatase , Frutose-Bifosfatase/genética , Frutose-Bifosfatase/metabolismo , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Glucose/metabolismo , Gluconeogênese , Homeostase
7.
Angiogenesis ; 24(3): 613-630, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33655414

RESUMO

Angiogenesis crucially contributes to various diseases, such as cancer and diabetic retinopathy. Hence, anti-angiogenic therapy is considered as a powerful strategy against these diseases. Previous studies reported that the acyclic monoterpene linalool exhibits anticancer, anti-inflammatory and anti-oxidative activity. However, the effects of linalool on angiogenesis still remain elusive. Therefore, we investigated the action of (3R)-(-)-linalool, a main enantiomer of linalool, on the angiogenic activity of human dermal microvascular endothelial cells (HDMECs) by a panel of angiogenesis assays. Non-cytotoxic doses of linalool significantly inhibited HDMEC proliferation, migration, tube formation and spheroid sprouting. Linalool also suppressed the vascular sprouting from rat aortic rings. In addition, Matrigel plugs containing linalool exhibited a significantly reduced microvessel density 7 days after implantation into BALB/c mice. Mechanistic analyses revealed that linalool promotes the phosphorylation of extracellular signal-regulated kinase (ERK), downregulates the intracellular level of adenosine triphosphate (ATP) and activates the transient receptor potential cation channel subfamily M (melastatin) member (TRPM)8 in HDMECs. Inhibition of ERK signaling, supplementation of ATP and blockade of TRPM8 significantly counteracted linalool-suppressed HDMEC spheroid sprouting. Moreover, ATP supplementation completely reversed linalool-induced ERK phosphorylation. In addition, linalool-induced ERK phosphorylation inhibited the expression of bone morphogenetic protein (BMP)-2 and linalool-induced TRPM8 activation caused the inhibition of ß1 integrin/focal adhesion kinase (FAK) signaling. These findings indicate an anti-angiogenic effect of linalool, which is mediated by downregulating intracellular ATP levels and activating TRPM8.


Assuntos
Monoterpenos Acíclicos/farmacologia , Trifosfato de Adenosina/metabolismo , Derme , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/metabolismo , Microvasos/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Canais de Cátion TRPM , Animais , Linhagem Celular , Derme/irrigação sanguínea , Derme/metabolismo , Células Endoteliais/transplante , Xenoenxertos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Canais de Cátion TRPM/antagonistas & inibidores , Canais de Cátion TRPM/metabolismo
8.
Int J Mol Sci ; 22(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34830364

RESUMO

Statins represent the most prescribed class of drugs for the treatment of hypercholesterolemia. Effects that go beyond lipid-lowering actions have been suggested to contribute to their beneficial pharmacological properties. Whether and how statins act on macrophages has been a matter of debate. In the present study, we aimed at characterizing the impact of statins on macrophage polarization and comparing these to the effects of bempedoic acid, a recently registered drug for the treatment of hypercholesterolemia, which has been suggested to have a similar beneficial profile but fewer side effects. Treatment of primary murine macrophages with two different statins, i.e., simvastatin and cerivastatin, impaired phagocytotic activity and, concurrently, enhanced pro-inflammatory responses upon short-term lipopolysaccharide challenge, as characterized by an induction of tumor necrosis factor (TNF), interleukin (IL) 1ß, and IL6. In contrast, no differences were observed under long-term inflammatory (M1) or anti-inflammatory (M2) conditions, and neither inducible NO synthase (iNOS) expression nor nitric oxide production was altered. Statin treatment led to extracellular-signal regulated kinase (ERK) activation, and the pro-inflammatory statin effects were abolished by ERK inhibition. Bempedoic acid only had a negligible impact on macrophage responses when compared with statins. Taken together, our data point toward an immunomodulatory effect of statins on macrophage polarization, which is absent upon bempedoic acid treatment.


Assuntos
Colesterol/genética , Ácidos Dicarboxílicos/farmacologia , Ácidos Graxos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Animais , Anticolesterolemiantes/farmacologia , Células HEK293 , Humanos , Ativação de Macrófagos/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos
9.
Biochem Biophys Res Commun ; 523(3): 639-644, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31941600

RESUMO

CREB3 (Luman) is a family member of ER resident transcription factors, which are cleaved upon the induction of ER stress. Their N-terminal fragments shuttle into the nucleus where they regulate the transcription of target genes. Here, we found that human CREB3 is phosphorylated within its transcription activation domain on serine 46 by protein kinase CK2. Further analyses revealed that the phosphorylation of this site does neither affect the cleavage by S1P/S2P proteases, nor the nuclear localisation nor the transcriptional activity of CREB3. However, phosphorylation at serine 46 reduced the stability of CREB3.


Assuntos
Caseína Quinase II/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Sequência de Aminoácidos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/química , Células HEK293 , Humanos , Fosforilação , Estabilidade Proteica
10.
Mar Drugs ; 18(2)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32074969

RESUMO

BACKGROUND: The marine-derived triterpenoid frondoside A inhibits the phosphatidylinositol-3-kinase (PI3K) pathway in cancer cells. Because this pathway is also crucially involved in platelet activation, we studied the effect of frondoside A on thrombus formation. METHODS: Frondoside A effects on platelet viability, surface adhesion molecule expression, and intracellular signaling were analyzed by flow cytometry and Western blot. The effect of frondoside A was analyzed by photochemically induced thrombus formation in the mouse dorsal skinfold chamber model and by tail vein bleeding. RESULTS: Concentrations of up to 15 µM frondoside A did not affect the viability of platelets, but reduced their surface expression of P-selectin (CD62P) and the activation of glycoprotein (GP)IIb/IIIa after agonist stimulation. Additional mechanistic analyses revealed that this was mediated by downregulation of PI3K-dependent Akt and extracellular-stimuli-responsive kinase (ERK) phosphorylation. Frondoside A significantly prolonged the complete vessel occlusion time in the mouse dorsal skinfold chamber model of photochemically induced thrombus formation and also the tail vein bleeding time when compared to vehicle-treated controls. CONCLUSION: Our findings demonstrated that frondoside A inhibits agonist-induced CD62P expression and activation of GPIIb/IIIa. Moreover, frondoside A suppresses thrombus formation. Therefore, this marine-derived triterpenoid may serve as a lead compound for the development of novel antithrombotic drugs.


Assuntos
Glicosídeos/farmacologia , Trombose/tratamento farmacológico , Triterpenos/farmacologia , Animais , Plaquetas/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases , Fosforilação , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Trombose/induzido quimicamente
11.
Int J Mol Sci ; 21(11)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545257

RESUMO

Somatostatin is a peptide hormone, which most commonly is produced by endocrine cells and the central nervous system. In mammals, somatostatin originates from pre-prosomatostatin and is processed to a shorter form, i.e., somatostatin-14, and a longer form, i.e., somatostatin-28. The two peptides repress growth hormone secretion and are involved in the regulation of glucagon and insulin synthesis in the pancreas. In recent years, the processing and secretion of somatostatin have been studied intensively. However, little attention has been paid to the regulatory mechanisms that control its expression. This review provides an up-to-date overview of these mechanisms. In particular, it focuses on the role of enhancers and silencers within the promoter region as well as on the binding of modulatory transcription factors to these elements. Moreover, it addresses extracellular factors, which trigger key signaling pathways, leading to an enhanced somatostatin expression in health and disease.


Assuntos
Somatostatina/genética , Somatostatina/metabolismo , Animais , Comunicação Autócrina , Elementos Facilitadores Genéticos , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Int J Mol Sci ; 21(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630015

RESUMO

The regulation of insulin biosynthesis and secretion in pancreatic ß-cells is essential for glucose homeostasis in humans. Previous findings point to the highly conserved, ubiquitously expressed serine/threonine kinase CK2 as having a negative regulatory impact on this regulation. In the cell culture model of rat pancreatic ß-cells INS-1, insulin secretion is enhanced after CK2 inhibition. This enhancement is preceded by a rise in the cytosolic Ca2+ concentration. Here, we identified the serine residues S2362 and S2364 of the voltage-dependent calcium channel CaV2.1 as targets of CK2 phosphorylation. Furthermore, co-immunoprecipitation experiments revealed that CaV2.1 binds to CK2 in vitro and in vivo. CaV2.1 knockdown experiments showed that the increase in the intracellular Ca2+ concentration, followed by an enhanced insulin secretion upon CK2 inhibition, is due to a Ca2+ influx through CaV2.1 channels. In summary, our results point to a modulating role of CK2 in the CaV2.1-mediated exocytosis of insulin.


Assuntos
Canais de Cálcio Tipo N/metabolismo , Caseína Quinase II/metabolismo , Células Secretoras de Insulina/enzimologia , Insulina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Ratos
13.
Biochim Biophys Acta Mol Cell Res ; 1865(1): 57-66, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28964848

RESUMO

The proteoglycan nerve/glial antigen (NG) 2 is expressed on multiple cell types and mediates cell proliferation and migration. However, little is known about its function in gene regulation. In this study, we demonstrate that in pericytes and glioblastoma cells intercellular adhesion molecule (ICAM)-1, an essential protein for leukocyte adhesion and transmigration, underlies a NG2-dependent expression. As shown by flow cytometry, Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR), silencing of NG2 in human placenta-derived pericytes increased the expression of ICAM-1. Pathway analyses revealed that this is mediated by extracellular-regulated-kinases (ERK) 1/2 signaling. Moreover, leukocyte adhesion to NG2 siRNA-treated pericytes was significantly enhanced when compared to scrambled (scr) siRNA-treated control cells. In vivo, we detected increased ICAM-1 protein levels in the retina of mice lacking NG2 expression. To exclude that this novel mechanism is pericyte-specific, we additionally analyzed the expression of ICAM-1 in dependency of NG2 in two glioblastoma cell lines. We found that A1207 and M059K cells exhibit an inverse expression pattern of NG2 and ICAM-1. Finally, downregulation of NG2 in A1207 cells significantly increased ICAM-1 expression. Taken together, these findings indicate that NG2 may represent a promising target for the modulation of ICAM-1-mediated immune responses.


Assuntos
Antígenos/fisiologia , Molécula 1 de Adesão Intercelular/genética , Proteoglicanas/fisiologia , Animais , Antígenos/genética , Células Cultivadas , Regulação da Expressão Gênica , Células HEK293 , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteoglicanas/genética , Transdução de Sinais/genética
14.
Cell Tissue Res ; 378(2): 195-205, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31131431

RESUMO

Pancreatic islets are highly vascularized endocrine units. Accordingly, their adequate revascularization is of major importance for successful islet transplantation. The proteoglycan, nerve/glial antigen 2 (NG2) expressed in pericytes is a crucial regulator of angiogenesis. Therefore, we herein analyze whether this surface protein contributes to the revascularization of grafted islets. Islets were isolated from NG2+/+ (wild-type) and NG2-/- mice and their cellular composition was analyzed by immunohistochemical detection of insulin, glucagon, somatostatin and CD31. Moreover, insulin secretion was assessed by enzyme-linked immunosorbent assay (ELISA). In addition, isolated islets were transplanted into dorsal skinfold chambers of wild-type mice and their revascularization was determined by intravital fluorescence microscopy and immunohistochemistry. NG2+/+ and NG2-/- islets did not differ in their cellular composition and insulin secretion. However, transplanted NG2-/- islets exhibited a significantly lower functional capillary density and a reduced number of CD31-positive microvessels. These findings demonstrate that the loss of NG2 impairs the revascularization of transplanted islets, underlining the importance of this pericytic proteoglycan for islet engraftment.


Assuntos
Antígenos/fisiologia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Neovascularização Fisiológica/fisiologia , Pericitos/metabolismo , Proteoglicanas/fisiologia , Animais , Insulina/metabolismo , Ilhotas Pancreáticas/irrigação sanguínea , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pericitos/citologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
15.
Exp Dermatol ; 28(8): 940-947, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152558

RESUMO

In this study, we introduce the mouse dorsal skinfold chamber model as a valuable approach for the in vivo evaluation of topical formulations. For this purpose, dorsal skinfold chambers were implanted into BALB/c mice. Tumor necrosis factor (TNF)-α was administered to the chamber tissue for the local induction of inflammation followed by the application of diclofenac-containing or diclofenac-free (control) gel onto the skin of the chamber backside. Intravital fluorescence microscopy was repetitively performed throughout an observation period of 24 hours to study macromolecular leakage, leucocyte-endothelial cell interactions and microhaemodynamic parameters. In addition, infiltration of the inflamed tissue with different immune cell subtypes was assessed by immunohistochemistry. In a second set of experiments, the effect of dermal application of a diclofenac-containing gel on photochemically induced thrombus formation was analysed. It was observed that macromolecular leakage, numbers of adherent leucocytes and tissue infiltrating myeloperoxidase (MPO)-positive neutrophilic granulocytes and CD68-positive macrophages were significantly reduced in dorsal skinfold chambers treated with diclofenac-containing gel when compared to controls. Moreover, the diclofenac-containing gel exerted an anti-thrombotic activity, as indicated by a significantly prolonged complete vessel occlusion time. These findings demonstrate that the mouse dorsal skinfold chamber represents a valid and versatile tool to evaluate the effects of topical formulations in vivo.


Assuntos
Fármacos Dermatológicos , Modelos Animais , Administração Tópica , Animais , Diclofenaco , Camundongos Endogâmicos BALB C
16.
Platelets ; 30(4): 421-427, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30204035

RESUMO

Thrombus formation is dependent on the interaction of platelets, leukocytes and endothelial cells as well as proteins of the coagulation cascade. This interaction is tightly controlled by phospho-regulated pathways involving protein kinase CK2. A growing number of studies have demonstrated an important role of this kinase in the regulation of primary and secondary hemostasis. Inhibition of CK2 downregulates the expression of important adhesion molecules on platelets and endothelial cells, such as glycoprotein (GP)IIb/IIIa, P-selectin, von Willebrand factor and vascular cell adhesion molecule. Moreover, the reduced CK2-dependent phosphorylation of different coagulation factors prevents the conversion of fibrinogen to fibrin. Targeting these mechanisms may open the door for the development of novel anti-thrombotic therapies.


Assuntos
Caseína Quinase II/efeitos adversos , Células Endoteliais/metabolismo , Leucócitos/metabolismo , Trombose/genética , Humanos , Trombose/patologia
17.
Int J Mol Sci ; 20(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500224

RESUMO

Since diabetes is a global epidemic, the development of novel therapeutic strategies for the treatment of this disease is of major clinical interest. Diabetes is differentiated in two types: type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). T1DM arises from an autoimmune destruction of insulin-producing ß-cells whereas T2DM is characterized by an insulin resistance, an impaired insulin reaction of the target cells, and/or dysregulated insulin secretion. In the past, a growing number of studies have reported on the important role of the protein kinase CK2 in the regulation of the survival and endocrine function of pancreatic ß-cells. In fact, inhibition of CK2 is capable of reducing cytokine-induced loss of ß-cells and increases insulin expression as well as secretion by various pathways that are regulated by reversible phosphorylation of proteins. Moreover, CK2 inhibition modulates pathways that are involved in the development of diabetes and prevents signal transduction, leading to late complications such as diabetic retinopathy. Hence, targeting CK2 may represent a novel therapeutic strategy for the treatment of diabetes.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/metabolismo , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipoglicemiantes/farmacologia , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos
18.
FASEB J ; 31(8): 3321-3333, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28424351

RESUMO

MicroRNAs (miRNAs) are powerful regulators of diverse biologic processes. However, the function of most miRNAs in angiogenesis remains elusive. In this study, we identified miR-191-5p (miR-191) as a potent inhibitor of blood vessel development. Transfection of human dermal microvascular endothelial cells with miR-191 mimic (miR-191m) inhibited their proliferation, migration, and tube formation. Moreover, vascular sprouting of miR-191m-transfected mouse aortic rings was significantly reduced when compared with controls. Transfection with miR-191 inhibitor (miR-191i) induced proangiogenic effects. The anti- and proangiogenic activities of miR-191m and -191i were further demonstrated in vivo Additional molecular biologic analyses revealed that miR-191m activates NF-κB signaling by up-regulating the mRNA expression of p65. miR-191 also increased the mRNA levels of the antiangiogenic factors p21 and tissue inhibitor of metalloproteinase-1 and reduced the expression of the proangiogenic factors eNOS and matrix metalloproteinase-1 and -9. Blockade of NF-κB activation with Bay 11-7082 reversed the antiangiogenic effects of miR-191m. These findings indicate that miR-191 effectively suppresses angiogenesis by activation of the NF-κB signaling pathway.-Gu, Y., Ampofo, E., Menger, M. D., Laschke, M. W. miR-191 suppresses angiogenesis by activation of NF-κB signaling.


Assuntos
MicroRNAs/metabolismo , NF-kappa B/metabolismo , Neovascularização Fisiológica/fisiologia , Transdução de Sinais/fisiologia , Animais , Aorta/efeitos dos fármacos , Células Cultivadas , Humanos , Camundongos , MicroRNAs/genética , Nitrilas/farmacologia , Sulfonas/farmacologia
19.
Platelets ; 29(3): 277-287, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28503993

RESUMO

VS-5584 is a highly selective dual kinase inhibitor which suppresses phosphatidylinositol 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) activity. Because these kinases are crucially involved in primary hemostasis, we herein investigated the effect of this compound on thrombus formation in vitro and in vivo. Pretreatment of washed platelets (WP) or platelet-rich plasma (PRP) with VS-5584 inhibited the agonist-induced activation of surface glycoprotein complex (GP)IIb/IIIa and the upregulation of P-selectin. This was associated with a significantly reduced formation of platelet-leukocyte aggregates (PLA). VS-5584 further attenuated platelet aggregation and adhesion after agonist stimulation. In contrast, endothelial expression of intercellular adhesion molecule (ICAM)-1 and vascular cellular adhesion molecule (VCAM)-1 and secretion of von Willebrand Factor (vWF) were not affected by the dual kinase inhibitor. In vivo, VS-5584 inhibited photochemically induced thrombus formation as shown by a significantly prolonged time to complete vessel occlusion when compared to vehicle-treated controls. This was associated with an elevated tail vein bleeding time, indicating a potential hemorrhagic risk in VS-5584-treated mice. Taken together, these novel findings demonstrate that VS-5584 is a potent inhibitor of primary hemostasis targeting multiple platelet functions.


Assuntos
Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Trombose/etiologia , Trombose/metabolismo , Animais , Biomarcadores , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea , Plaquetas/metabolismo , Células Cultivadas , Células Endoteliais , Humanos , Camundongos , Ativação Plaquetária/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Trombose/tratamento farmacológico
20.
J Surg Res ; 215: 34-46, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28688659

RESUMO

BACKGROUND: Ischemia-reperfusion (I/R) induces tissue inflammation, which is characterized by an increased leukocyte-endothelial cell interaction and leukocyte transmigration. These processes are mediated by the activation of the nuclear factor (NF)κB signaling pathway, resulting in an elevated expression of specific adhesion molecules. The phytochemical indole-3-carbinol (I3C) has been shown to exert anti-inflammatory effects by interfering with NFκB signal transduction. The aim of the present study was to investigate whether I3C is capable of counteracting the pathogenesis of I/R injury. MATERIALS AND METHODS: We investigated the inhibitory effect of I3C on endothelial surface protein expression during hypoxia and reoxygenation by flow cytometry. Moreover, the subcellular localization of NFκB was analyzed by immunofluorescence and Western blot. Adhesion protein levels on leukocytes after tumor necrosis factor-α stimulation were determined using flow cytometry. Finally, leukocyte-endothelial cell interaction and leukocyte transmigration during I/R was investigated in dorsal skinfold chambers of BALB/c mice by means of repetitive intravital fluorescence microscopy and immunohistochemistry. RESULTS: I3C suppressed the expression of E-selectin and intercellular adhesion molecule-1 on human dermal microvascular endothelial cells by reducing the transcriptional activity of NFκB. Furthermore, surface protein levels of macrophage-1 antigen as well as activated lymphocyte function-associated antigen-1 were markedly reduced on I3C-treated leukocytes. In vivo, I3C treatment decreased the numbers of adherent and transmigrated leukocytes. This was associated with a reduced macromolecular leakage when compared with vehicle-treated controls. CONCLUSIONS: These novel results indicate that I3C reduces the expression of endothelial and leukocytic adhesion proteins, resulting in attenuated leukocyte-endothelial cell interactions during I/R. Accordingly, dietary supplements containing I3C may be beneficial for the treatment of I/R-induced inflammation.


Assuntos
Indóis/uso terapêutico , Inflamação/prevenção & controle , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Animais , Biomarcadores/metabolismo , Western Blotting , Selectina E/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Citometria de Fluxo , Imunofluorescência , Imuno-Histoquímica , Indóis/farmacologia , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/metabolismo
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