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1.
Braz J Med Biol Res ; 44(7): 624-33, 2011 07.
Artigo em Inglês | MEDLINE | ID: mdl-21833458

RESUMO

Selectins play an essential role in most inflammatory reactions, mediating the initial leukocyte-rolling event on activated endothelium. Heparin and dermatan sulfate (DS) bind and block P- and L-selectin function in vitro. Recently, we reported that subcutaneous administration of DS inhibits colon inflammation in rats by reducing macrophage and T-cell recruitment and macrophage activation. In the present study, we examined the effect of porcine intestinal mucosa DS on renal inflammation and fibrosis in mice after unilateral ureteral obstruction (UUO). Twenty-four adult male Swiss mice weighing 20-25 g were divided into 4 groups: group C (N = 6) was not subjected to any surgical manipulation; group SH (N = 6) was subjected to surgical manipulation but without ureter ligation; group UUO (N = 6) was subjected to unilateral ureteral obstruction and received no treatment; group UUO plus DS (N = 6) was subjected to UUO and received DS (4 mg/kg) subcutaneously daily for 14 days. An immunoblot study was also performed for TGF-ß. Collagen (stained area ~3700 µm(2)), MCP-1 (stained area ~1700 µm(2)), TGF-ß (stained area ~13% of total area), macrophage (number of cells ~40), and myofibroblast (stained area ~1900 µm(2)) levels were significantly (P < 0.05) higher in the UUO group compared to control. DS treatment significantly (P < 0.05) reduced the content of collagen (stained area ~700 µm(2)), MCP-1 (stained area ~160 µm(2)) and TGF-ß (stained area ~5% of total area), in addition to myofibroblast (stained area ~190 µm(2)) and macrophage (number of cells ~32) accumulation in the obstructed kidney. Overall, these results indicate that DS attenuates kidney inflammation by reducing macrophage recruitment, myofibroblast population and fibrosis in mice submitted to UUO.


Assuntos
Anti-Inflamatórios/farmacologia , Quimiocina CCL2/metabolismo , Dermatan Sulfato/farmacologia , Macrófagos/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Fator de Crescimento Transformador beta/biossíntese , Obstrução Ureteral/complicações , Animais , Anti-Inflamatórios/administração & dosagem , Dermatan Sulfato/administração & dosagem , Modelos Animais de Doenças , Fibrose , Injeções Subcutâneas , Rim/patologia , Ativação de Macrófagos , Macrófagos/metabolismo , Masculino , Camundongos , Miofibroblastos/metabolismo , Nefrite/prevenção & controle , Obstrução Ureteral/patologia
2.
Braz. j. med. biol. res ; 44(7): 624-633, July 2011. ilus
Artigo em Inglês | LILACS | ID: lil-595694

RESUMO

Selectins play an essential role in most inflammatory reactions, mediating the initial leukocyte-rolling event on activated endothelium. Heparin and dermatan sulfate (DS) bind and block P- and L-selectin function in vitro. Recently, we reported that subcutaneous administration of DS inhibits colon inflammation in rats by reducing macrophage and T-cell recruitment and macrophage activation. In the present study, we examined the effect of porcine intestinal mucosa DS on renal inflammation and fibrosis in mice after unilateral ureteral obstruction (UUO). Twenty-four adult male Swiss mice weighing 20-25 g were divided into 4 groups: group C (N = 6) was not subjected to any surgical manipulation; group SH (N = 6) was subjected to surgical manipulation but without ureter ligation; group UUO (N = 6) was subjected to unilateral ureteral obstruction and received no treatment; group UUO plus DS (N = 6) was subjected to UUO and received DS (4 mg/kg) subcutaneously daily for 14 days. An immunoblot study was also performed for TGF-β. Collagen (stained area ~3700 µm²), MCP-1 (stained area ~1700 µm²), TGF-β (stained area ~13 percent of total area), macrophage (number of cells ~40), and myofibroblast (stained area ~1900 µm²) levels were significantly (P < 0.05) higher in the UUO group compared to control. DS treatment significantly (P < 0.05) reduced the content of collagen (stained area ~700 µm²), MCP-1 (stained area ~160 µm²) and TGF-β (stained area ~5 percent of total area), in addition to myofibroblast (stained area ~190 µm²) and macrophage (number of cells ~32) accumulation in the obstructed kidney. Overall, these results indicate that DS attenuates kidney inflammation by reducing macrophage recruitment, myofibroblast population and fibrosis in mice submitted to UUO.


Assuntos
Animais , Masculino , Camundongos , Anti-Inflamatórios/farmacologia , /metabolismo , Dermatan Sulfato/farmacologia , Macrófagos/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Fator de Crescimento Transformador beta/biossíntese , Obstrução Ureteral/complicações , Anti-Inflamatórios/administração & dosagem , Modelos Animais de Doenças , Dermatan Sulfato/administração & dosagem , Fibrose , Injeções Subcutâneas , Rim/patologia , Ativação de Macrófagos , Macrófagos/metabolismo , Miofibroblastos/metabolismo , Nefrite/prevenção & controle , Obstrução Ureteral/patologia
3.
J Thromb Haemost ; 9(9): 1807-15, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21676168

RESUMO

BACKGROUND: Cancer-associated thrombosis and enduring inflammation are strongly associated with cancer progression and metastasis. Heparin is the mostly clinically used anticoagulant/antithrombotic drug, and has recently been shown to exhibit antimetastatic and anti-inflammatory activities that are linked to inhibition of P-selectin and/or L-selectin. P-selectin-mediated platelet-tumor cell and tumor cell-endothelium interactions facilitate the initial steps of metastasis. OBJECTIVES AND METHODS: The aim of the present study was to determine the capacity of dermatan sulfates to inhibit P-selectin and to test their potential to affect thrombosis, inflammation and metastasis in respective experimental mouse models. RESULTS: Two dermatan sulfates isolated from the ascidians Styela plicata and Phallusia nigra, composed of the same disaccharide core structure (IdoA2-GalNAc)(n) , but sulfated at carbon 4 or 6 of the GalNAc, respectively, have opposed heparin cofactor II (HCII) activities and are potent inhibitors of P-selectin. The ascidian dermatan sulfates effectively attenuated metastasis of both MC-38 colon carcinoma and B16-BL6 melanoma cells and the infiltration of inflammatory cells in a thioglycollate peritonitis mouse model. Moreover, both glycosaminoglycans reduced thrombus size in an FeCl(3) -induced arterial thrombosis model, irrespective of their HCII activities. The analysis of arterial thrombi demonstrated markedly reduced platelet deposition after dermatan sulfate treatment, suggesting that the glycosaminoglycan inhibited P-selectin and thereby the binding of activated platelets during thrombus formation. CONCLUSIONS: Collectively, these findings provide evidence that specific inhibition of P-selectin represents a potential therapeutic target in thrombosis, inflammation and metastasis, and that ascidian dermatan sulfates may serve as antiselectin agents.


Assuntos
Dermatan Sulfato/farmacologia , Selectina-P/antagonistas & inibidores , Urocordados/química , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/secundário , Dermatan Sulfato/isolamento & purificação , Humanos , Inflamação/prevenção & controle , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/secundário , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Metástase Neoplásica/prevenção & controle , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/secundário , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Selectina-P/genética , Selectina-P/fisiologia , Trombose/prevenção & controle
4.
Braz J Med Biol Res ; 39(11): 1409-15, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17146553

RESUMO

In the ascidian Styela plicata, the oocytes are surrounded by two types of accessory cells named follicle cells and test cells. A heparin-like substance with an anticoagulant activity equivalent to 10% of mammalian heparin and about 5% as potent as the mammalian counterpart for the inhibition of thrombin by antithrombin was isolated from the oocyte test cells. In the present study, we compared the antithrombotic and hemorrhagic effects of sea squirt oocyte test cell heparin with those of porcine heparin in rat models of venous thrombosis and blood loss. Intravenous administration of the oocyte test cell heparin to Wistar rats (both sexes, weighing approximately 300 g, N = 4 in each group) at a dose of 5.0 mg/kg body weight, which produced a 1.8-fold increase in plasma activated partial thromboplastin time, inhibited thrombosis by 45 +/- 13.5% (mean +/- SD) without any bleeding effect. The same dose of porcine heparin inhibited thrombosis by 100 +/- 1.4%, but produced a blood loss three times greater than that of the saline-treated control. However, 10-fold reduction of the dose of porcine heparin to 0.5 mg/kg body weight, which produced a 5-fold increase in plasma-activated partial thromboplastin time, inhibited thrombosis by 70 +/- 13% without any bleeding effect. The antithrombotic properties of a new heparin isolated from test cells of the sea squirt S. plicata, reported here for the first time, indicate that, although sea squirt oocyte test cell heparin was a poor anticoagulant compared to porcine heparin, it had a significant antithrombotic effect without causing bleeding.


Assuntos
Anticoagulantes/isolamento & purificação , Antitrombinas/isolamento & purificação , Heparina/isolamento & purificação , Oócitos/química , Urocordados/química , Trombose Venosa/prevenção & controle , Animais , Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Modelos Animais de Doenças , Inibidores do Fator Xa , Feminino , Hemorragia/tratamento farmacológico , Heparina/uso terapêutico , Masculino , Tempo de Tromboplastina Parcial , Ratos , Ratos Wistar , Suínos , Urocordados/citologia
5.
Braz. j. med. biol. res ; 39(11): 1409-1415, Nov. 2006. graf, tab
Artigo em Inglês | LILACS | ID: lil-437832

RESUMO

In the ascidian Styela plicata, the oocytes are surrounded by two types of accessory cells named follicle cells and test cells. A heparin-like substance with an anticoagulant activity equivalent to 10 percent of mammalian heparin and about 5 percent as potent as the mammalian counterpart for the inhibition of thrombin by antithrombin was isolated from the oocyte test cells. In the present study, we compared the antithrombotic and hemorrhagic effects of sea squirt oocyte test cell heparin with those of porcine heparin in rat models of venous thrombosis and blood loss. Intravenous administration of the oocyte test cell heparin to Wistar rats (both sexes, weighing ~300 g, N = 4 in each group) at a dose of 5.0 mg/kg body weight, which produced a 1.8-fold increase in plasma activated partial thromboplastin time, inhibited thrombosis by 45 ± 13.5 percent (mean ± SD) without any bleeding effect. The same dose of porcine heparin inhibited thrombosis by 100 ± 1.4 percent, but produced a blood loss three times greater than that of the saline-treated control. However, 10-fold reduction of the dose of porcine heparin to 0.5 mg/kg body weight, which produced a 5-fold increase in plasma-activated partial thromboplastin time, inhibited thrombosis by 70 ± 13 percent without any bleeding effect. The antithrombotic properties of a new heparin isolated from test cells of the sea squirt S. plicata, reported here for the first time, indicate that, although sea squirt oocyte test cell heparin was a poor anticoagulant compared to porcine heparin, it had a significant antithrombotic effect without causing bleeding.


Assuntos
Animais , Masculino , Feminino , Ratos , Anticoagulantes/isolamento & purificação , Antitrombinas/isolamento & purificação , Heparina/isolamento & purificação , Oócitos/química , Urocordados/química , Trombose Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Modelos Animais de Doenças , Fator Xa/antagonistas & inibidores , Hemorragia/tratamento farmacológico , Heparina/uso terapêutico , Tempo de Tromboplastina Parcial , Ratos Wistar , Suínos , Urocordados/citologia
6.
Matrix Biol ; 25(7): 457-61, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16934446

RESUMO

Dermatan sulfate (DS) is a member of the glycosaminoglycan (GAG) family and is primarily located in the extracellular matrix. Using a modified phage display procedure, we selected 2 different antibodies against DS of which one antibody, LKN1, was specific for DS. LKN1 was especially reactive with 4/2,4-di-O-sulfated DS, and did not react with other classes of GAGs including chondroitin sulfate and heparan sulfate. Immunohistochemical analysis of kidney, skin and tendon showed a typical fibrillar staining pattern, co-localizing with type I collagen. Staining was abolished by specific enzymatic digestion of DS. Immunoelectron microscopy confirmed the association of the DS epitope with collagen fibrils. The location of DS did not follow the main banding period of collagen, which is in line with the current concept that the core protein rather than the DS moiety of DS-proteoglycans specifically binds to collagen fibrils. This unique anti-DS antibody and the availability of its coding DNA may be instrumental in studies of the structure and function of DS.


Assuntos
Anticorpos/imunologia , Dermatan Sulfato/imunologia , Biblioteca de Peptídeos , Animais , Anticorpos/genética , Especificidade de Anticorpos , Colágeno Tipo I/metabolismo , Dermatan Sulfato/metabolismo , Epitopos/metabolismo , Humanos , Rim/imunologia , Microscopia Imunoeletrônica , Pele/imunologia , Tendões/imunologia
7.
Biochem Soc Trans ; 31(2): 352-3, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12653636

RESUMO

Hepatocyte growth factor (HGF)/scatter factor (SF) is a unique growth factor, in that it binds both heparan sulphate (HS) and dermatan sulphate (DS). The sequences in HS and DS that specifically interact with and modulate HGF/SF activity have not yet been fully identified. Ascidian DS, which uniquely possesses O-sulphation at C-6 (and not C-4) of its N -acetylgalactosamine unit, was analysed for HGF/SF-binding activity in the biosensor. The kinetic analysis revealed a strong, biologically relevant interaction with an equilibrium dissociation constant ( K (d)) of approx. 1 nM. An Erk activation assay also demonstrated stimulation of the MAP kinase pathway downstream of the Met receptor following addition of both HGF/SF and ascidian DS to the glycosaminoglycan-deficient CHO-745 mutant cell line. Furthermore, the activation of Met and the MAP kinase pathway by HGF/SF and ascidian DS leads to a cellular response in the form of migration.


Assuntos
Dermatan Sulfato/metabolismo , Heparitina Sulfato/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Animais , Humanos , Cinética , Ligação Proteica , Transdução de Sinais
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