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1.
Intern Med ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38811229

RESUMO

A 69-year-old man was diagnosed with follicular lymphoma (Grade 3A). Obinutuzumab combined with bendamustine (OB) therapy was initiated as salvage chemotherapy. Nausea, abdominal pain, and hyponatremia appeared after six courses of OB therapy; cytomegalovirus (CMV) enteritis with primary adrenal insufficiency (PAI) was a complication. Ganciclovir and hydrocortisone were administered, and the clinical findings improved. PAI caused by CMV infection has mainly been reported in patients with acquired immunodeficiency syndrome. In the present case, the PAI triggered by CMV infection led to immunodeficiency after chemotherapy.

2.
Kidney Int ; 102(3): 536-545, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35597365

RESUMO

Dysregulation of fatty acid utilization is increasingly recognized as a significant component of diabetic kidney disease. Rho-associated, coiled-coil-containing protein kinase (ROCK) is activated in the diabetic kidney, and studies over the past decade have illuminated ROCK signaling as an essential pathway in diabetic kidney disease. Here, we confirmed the distinct role of ROCK1, an isoform of ROCK, in fatty acid metabolism using glomerular mesangial cells and ROCK1 knockout mice. Mesangial cells with ROCK1 deletion were protected from mitochondrial dysfunction and redox imbalance driven by transforming growth factor ß, a cytokine upregulated in diabetic glomeruli. We found that high-fat diet-induced obese ROCK1 knockout mice exhibited reduced albuminuria and histological abnormalities along with the recovery of impaired fatty acid utilization and mitochondrial fragmentation. Mechanistically, we found that ROCK1 regulates the induction of critical mediators in fatty acid metabolism, including peroxisome proliferator-activated receptor gamma coactivator 1α, carnitine palmitoyltransferase 1, and widespread program-associated cellular metabolism. Thus, our findings highlight ROCK1 as an important regulator of energy homeostasis in mesangial cells in the overall pathogenesis of diabetic kidney disease.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Quinases Associadas a rho , Animais , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Camundongos , Camundongos Knockout , Transdução de Sinais , Quinases Associadas a rho/metabolismo
3.
Commun Biol ; 5(1): 341, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35396346

RESUMO

Loss of podocytes is a common feature of diabetic renal injury and a key contributor to the development of albuminuria. We found that podocyte Rho associated coiled-coil containing protein kinase 2 (ROCK2) is activated in rodent models and patients with diabetes. Mice that lacked ROCK2 only in podocytes (PR2KO) were resistant to albuminuria, glomerular fibrosis, and podocyte loss in multiple animal models of diabetes (i.e., streptozotocin injection, db/db, and high-fat diet feeding). RNA-sequencing of ROCK2-null podocytes provided initial evidence suggesting ROCK2 as a regulator of cellular metabolism. In particular, ROCK2 serves as a suppressor of peroxisome proliferator-activated receptors α (PPARα), which rewires cellular programs to negatively control the transcription of genes involved in fatty acid oxidation and consequently induce podocyte apoptosis. These data establish ROCK2 as a nodal regulator of podocyte energy homeostasis and suggest this signaling pathway as a promising target for the treatment of diabetic podocytopathy.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Podócitos , Albuminúria/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Humanos , Camundongos , Podócitos/metabolismo , Estreptozocina/efeitos adversos , Estreptozocina/metabolismo , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
4.
JMA J ; 3(3): 154-163, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33150249

RESUMO

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease and is strongly associated with cardiovascular mortality. Given the pandemic of obesity and diabetes, the elucidation of the molecular underpinnings of DKD and establishment of effective therapy are urgently required. Studies over the past decade have identified the activated renin-angiotensin system (RAS) and hemodynamic changes as important therapeutic targets. However, given the residual risk observed in patients treated with RAS inhibitors and/or sodium glucose co-transporter 2 inhibitors, the involvement of other molecular machinery is likely, and the elucidation of such pathways represents fertile ground for the development of novel strategies. Rho-kinase (ROCK) is a serine/threonine kinase that is under the control of small GTPase protein Rho. Many fundamental cellular processes, including migration, proliferation, and survival are orchestrated by ROCK through a mechanism involving cytoskeletal reorganization. From a pathological standpoint, several analyses provide compelling evidence supporting the hypothesis that ROCK is an important regulator of DKD that is highly pertinent to cardiovascular disease. In cell-based studies, ROCK is activated in response to a diverse array of external stimuli associated with diabetes, and renal ROCK activity is elevated in the context of type 1 and 2 diabetes. Experimental studies have demonstrated the efficacy of pharmacological or genetic inhibition of ROCK in the prevention of diabetes-related histological and functional abnormalities in the kidney. Through a bird's eye view of ROCK in renal biology, the present review provides a conceptual framework that may be widely applicable to the pathological processes of multiple organs and illustrate novel therapeutic promise in diabetology.

5.
Am J Physiol Renal Physiol ; 317(4): F839-F851, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364374

RESUMO

The small GTPase Rho and its effector Rho kinase (ROCK) are involved in the pathogenesis of diabetic kidney disease. Rho kinase has two isoforms: ROCK1 and ROCK2. However, it remains unclear which is mainly involved in the progression of diabetic glomerulosclerosis and the regulation of profibrotic mediators. Glomeruli isolated from type 2 diabetic db/db mice demonstrated increased gene expression of transforming growth factor (TGF)-ß and its downstream profibrotic mediators. Chemical inhibition of ROCK suppressed the expression of profibrotic mediators in both isolated glomeruli and cultured mesangial cells. An investigation of mechanisms underlying this observation revealed activated ROCK functions through the phosphorylation of JNK and Erk and the nuclear translocation of NF-κB via actin dynamics. Knockdown by siRNA against ROCK1 and ROCK2 showed that ROCK2 but not ROCK1 controls this fibrotic machinery. Further in vivo experiments showed that ROCK2 activity in the renal cortex of db/db mice was elevated compared with control db/m mice. Importantly, oral administration of ROCK2 inhibitor attenuated renal ROCK2 activity, albuminuria, and glomerular fibrosis in db/db mice. These observations indicate that ROCK2 is a key player in the development of diabetic renal injury. Glomerular ROCK2 may be a potential therapeutic target for the treatment of diabetic kidney disease.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/biossíntese , Citoesqueleto/metabolismo , Fibrose/genética , Mesângio Glomerular/metabolismo , NF-kappa B/biossíntese , Fator de Crescimento Transformador beta/farmacologia , Quinases Associadas a rho/metabolismo , Actinas/metabolismo , Animais , Nefropatias Diabéticas/metabolismo , Ativação Enzimática , Mesângio Glomerular/citologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Quinases Associadas a rho/antagonistas & inibidores
6.
Int J Mol Sci ; 20(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884801

RESUMO

The small GTPase Rho and its downstream effector, Rho-kinase (ROCK), regulate various cellular functions, including organization of the actin cytoskeleton, cell adhesion and migration. A pro-inflammatory lipid mediator, lysophosphatidic acid (LPA), is a potent activator of the Rho/ROCK signalling pathway and has been shown to induce the expression of chemokines and cell adhesion molecules (CAMs). In the present study, we aimed to elucidate the precise mechanism by which ROCK regulates LPA-induced expressions and functions of chemokines and CAMs. We observed that ROCK blockade reduced LPA-induced phosphorylation of IκBα and inhibited NF-κB RelA/p65 phosphorylation, leading to attenuation of RelA/p65 nuclear translocation. Furthermore, small interfering RNA-mediated ROCK isoform knockdown experiments revealed that LPA induces the expression of monocyte chemoattractant protein-1 (MCP-1) and E-selectin via ROCK2 in human aortic endothelial cells (HAECs). Importantly, we found that ROCK2 but not ROCK1 controls LPA-induced monocytic migration and monocyte adhesion toward endothelial cells. These findings demonstrate that ROCK2 is a key regulator of endothelial inflammation. We conclude that targeting endothelial ROCK2 is potentially effective in attenuation of atherosclerosis.


Assuntos
Aterosclerose/genética , Células Endoteliais/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Quinases Associadas a rho/genética , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/genética , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Aorta/citologia , Aorta/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Adesão Celular/genética , Movimento Celular/efeitos dos fármacos , Quimiocina CCL2/genética , Selectina E/genética , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Quinase I-kappa B/genética , Monócitos/efeitos dos fármacos , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética , Quinases Associadas a rho/metabolismo
7.
Int J Mol Sci ; 18(8)2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28820432

RESUMO

Podocyte apoptosis is a key process in the onset of diabetic nephropathy. A significant body of evidence shows that the Notch signaling pathway plays a central role in this process. We found that Rho-kinase mediates transforming growth factor ß (TGF-ß)-induced Notch ligand Jag1 expression. Importantly, TGF-ß-mediated podocyte apoptosis was attenuated by Rho-kinase inhibition. Mechanistically, Rho-kinase regulated Jag1 induction via the extracellular signal-regulated kinase (ERK) 1/2 and c-Jun N-terminal kinase (JNK) but not Smad pathways. Consistently, the Rho-kinase inhibitor fasudil prevented albuminuria and the urinary excretion of nephrin in db/db mice and reduced the prevalence of podocyte apoptosis and Jag1 expression. Finally, the expression of Jag1 and apoptosis markers such as Bax and cyclin-dependent kinase inhibitor 1A (CDKN1A) was decreased in podocytes derived from db/db mice treated with fasudil. The present study provides evidence that Rho-kinase plays a key role in podocyte apoptosis. Rho-kinase is an attractive therapeutic target for diabetic nephropathy.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Apoptose/efeitos dos fármacos , Nefropatias Diabéticas/metabolismo , Podócitos/efeitos dos fármacos , Receptores Notch/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Albuminúria/metabolismo , Albuminúria/prevenção & controle , Animais , Linhagem Celular , Células Cultivadas , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/patologia , Proteína Jagged-1/metabolismo , Masculino , Proteínas de Membrana/urina , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Podócitos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Quinases Associadas a rho/metabolismo
8.
Histochem Cell Biol ; 144(3): 249-59, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26026990

RESUMO

Glucagon-like peptide-1 (GLP-1) is thought to preserve neurons and glia following axonal injury and neurodegenerative disorders. We investigated the neurotrophic and neuroprotective properties of exendin (Ex)-4, a synthetic GLP-1 receptor (GLP-1R) agonist, on adult rat dorsal root ganglion (DRG) neurons and PC12 cells. GLP-1R was predominantly localized on large and small peptidergic neurons in vivo and in vitro, suggesting the involvement of GLP-1 in both the large and small sensory fiber functions. Ex-4 dose-dependently (1 ≤ 10 ≤ 100 nM) promoted neurite outgrowth and neuronal survival at 2 and 7 days in culture, respectively. Treatment with 100 nM Ex-4 restored the reduced neurite outgrowth and viability of DRG neurons caused by the insulin removal from the medium and suppressed the activity of RhoA, an inhibitory regulator for peripheral nerve regeneration, in PC12 cells. Furthermore, these effects were attenuated by co-treatment with phosphatidylinositol-3'-phosphate kinase (PI3K) inhibitor, LY294002. These findings imply that Ex-4 enhances neurite outgrowth and neuronal survival through the activation of PI3K signaling pathway, which negatively regulates RhoA activity. Ex-4 and other GLP-1R agonists may compensate for the reduced insulin effects on neurons, thereby being beneficial for the treatment of diabetic neuropathy.


Assuntos
Gânglios Espinais/fisiologia , Insulina/fisiologia , Neurônios/fisiologia , Fármacos Neuroprotetores/farmacologia , Peptídeos/farmacologia , Peçonhas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Exenatida , Feminino , Gânglios Espinais/citologia , Gânglios Espinais/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Morfolinas/farmacologia , Neuritos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células PC12 , Inibidores de Fosfoinositídeo-3 Quinase , Ratos , Ratos Wistar , Receptores de Glucagon/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/fisiologia
9.
Am J Physiol Renal Physiol ; 307(5): F571-80, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25007875

RESUMO

The small GTPase Rho and its downstream effector, Rho-associated coiled-coil containing protein kinase (Rho-kinase), regulate a number of cellular processes, including organization of the actin cytoskeleton, cell adhesion, and migration. While pharmacological inhibitors of Rho-kinase signaling are known to block renal inflammation, the molecular basis for this effect is unclear. Here, we provide evidence that proinflammatory TNF-α promotes mesangial expression of macrophage colony-stimulating factor (M-CSF), a key regulator for the growth and differentiation of mononuclear phagocytes, in a Rho-kinase-dependent manner. Consistent with this observation, TNF-α-mediated renal expression of M-CSF in insulin-resistant db/db mice was downregulated by Rho-kinase inhibition. Small interfering RNA-facilitated knockdown of Rho-kinase isoforms ROCK1 and ROCK2 indicated that both isoforms make comparable contributions to regulation of M-CSF expression in mesangial cells. From a mechanistic standpoint, Western blotting and EMSA showed that Rho-kinase and its downstream target p38 MAPK regulate nuclear translocation of NF-κB RelA/p65 and subsequent DNA binding activity, with no significant effects on IκBα degradation and RelA/p65 phosphorylation. Moreover, we showed that Rho-kinase-mediated cytoskeletal organization is required for the nuclear uptake of RelA/p65. Collectively, these findings identify Rho-kinase as a critical regulator of chemokine expression and macrophage proliferation.


Assuntos
Fator Estimulador de Colônias de Macrófagos/metabolismo , Células Mesangiais/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases Associadas a rho/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Quimiocinas/metabolismo , Citoesqueleto/metabolismo , Técnicas In Vitro , Macrófagos/citologia , Masculino , Células Mesangiais/citologia , Camundongos , Camundongos Endogâmicos , Modelos Animais , Transporte Proteico
10.
Clin Exp Nephrol ; 18(6): 844-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24463961

RESUMO

BACKGROUND: Sphingosine-1-phosphate (S1P) is reportedly involved in the pathogenesis of kidney disease; however, the precise role played by S1P in renal disorders still remains controversial. Rho kinase plays an important role in the development of diabetic nephropathy by inducing glomerular and tubulointerstitial fibrosis. Rho kinase is known to be stimulated by S1P through its specific receptor, S1P2 receptor (S1P2). Hence, we investigated whether S1P-S1P2 signaling plays a role in the epithelial-mesenchymal transition (EMT) through Rho kinase activation in renal tubules. METHOD: To characterize the distribution of the S1P2, an immunohistochemical examination of the receptor was performed in the kidney of the non-diabetic and diabetic mice. Next, we examined Rho kinase activity as well as E-cadherin and alpha-smooth muscle actin (α-SMA) expression by real-time RT-PCR and western blotting in cultured rat tubular epithelial cells under S1P stimulation with and without a Rho kinase inhibitor and an S1P2 blocker. In addition, the distribution of E-cadherin and α-SMA was examined by immunocytochemistry. RESULT: S1P2 was expressed mainly in the renal tubules; expression was intense in collecting ducts and distal tubules compared to other segments. S1P induced activation of Rho kinase through the S1P2, which changed the distribution of E-cadherin and increased the expression of α-SMA. CONCLUSION: Rho kinase activation by S1P via S1P2 initiated EMT changes in cultured renal tubular cells. Our results suggest that excessive stimulation of S1P might facilitate renal fibrosis via activation of Rho kinase through S1P2.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Túbulos Renais/patologia , Lisofosfolipídeos/farmacologia , Receptores de Lisoesfingolipídeo/fisiologia , Esfingosina/análogos & derivados , Quinases Associadas a rho/fisiologia , Actinas/fisiologia , Animais , Caderinas/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Células Epiteliais/patologia , Células Epiteliais/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Túbulos Renais/fisiologia , Masculino , Camundongos , Camundongos Knockout , Receptores para Leptina/deficiência , Receptores para Leptina/genética , Receptores para Leptina/fisiologia , Esfingosina/farmacologia
11.
Biochem Biophys Res Commun ; 435(2): 171-5, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23665024

RESUMO

The process of atherosclerosis is affected by interactions among numerous biological pathways. Accumulating evidence shows that endoplasmic reticulum (ER) stress plays a crucial role in the development of atherosclerosis. Rho-kinase is an effector of small GTP-binding protein Rho, and has been implicated as an atherogenic factor. Previous studies demonstrated that fasudil, a specific Rho-kinase inhibitor, exerts a cardioprotective effect by downregulating ER stress signaling. However, the molecular link between ER stress and Rho-kinase in endothelial cells has not been elucidated. In this study, we investigated the mechanisms by which fasudil regulates endothelial inflammation during ER stress. Tunicamycin, an established ER stress inducer, increased vascular cellular adhesion molecule (VCAM)-1 expression in endothelial cells. Intriguingly, fasudil inhibited VCAM-1 induction. From a mechanistic stand point, fasudil inhibited expression of activating transcription factor (ATF)4 and subsequent C/EBP homologous protein (CHOP) induction by tunicamycin. Furthermore, fasudil attenuated tunicamycin-induced phophorylation of p38MAPK that is crucial for the atherogenic response during ER stress. These findings indicate that Rho-kinase regulates ER stress-mediated VCAM-1 induction by ATF4- and p38MAPK-dependent signaling pathways. Rho-kinase inhibition by fasudil would be an important therapeutic approach against atherosclerosis, in particular, under conditions of ER stress.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Estresse do Retículo Endoplasmático/fisiologia , Células Endoteliais/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Quinases Associadas a rho/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Células Cultivadas , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Humanos , Dobramento de Proteína/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Estresse Fisiológico , Resposta a Proteínas não Dobradas/efeitos dos fármacos
12.
Kidney Int ; 84(3): 545-54, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23615507

RESUMO

The small GTPase Rho and its effector Rho-kinase are involved in the pathogenesis of diabetic nephropathy. Accumulating evidence shows that hypoxia-inducible factor-1α (HIF-1α) is a key regulator of renal sclerosis under diabetic conditions. However, the interactions of Rho-kinase and HIF-1α in the development of renal dysfunction have not been defined. Here, we assessed whether Rho-kinase blockade attenuates HIF-1α induction and the subsequent fibrotic response using type 2 diabetic mice and cultured mesangial cells. Fasudil, a Rho-kinase inhibitor, reduced urinary albumin excretion, mesangial matrix expansion, and the expression of fibrotic mediators in db/db mice. Mechanistically, HIF-1α accumulation and the expression of its target genes that contribute to diabetic glomerulosclerosis were also prevented by fasudil in the renal cortex. In mesangial cells, Rho/Rho-kinase signaling was activated under hypoxic conditions. Further in vitro studies showed that pharmacological and genetic inhibition of Rho-kinase promoted proteasomal HIF-1α degradation, which subsequently suppressed HIF-1-dependent profibrotic gene expression by upregulation of prolyl hydroxylase 2. Thus, we found a previously unrecognized renoprotective mechanism for the effects of Rho-kinase inhibition and this could be a potential therapeutic target for the treatment of diabetic nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/prevenção & controle , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Albuminúria/metabolismo , Albuminúria/prevenção & controle , Animais , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Fibrose , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Córtex Renal/metabolismo , Córtex Renal/patologia , Masculino , Camundongos , Camundongos Mutantes , Inibidores de Proteínas Quinases/farmacologia , Quinases Associadas a rho/efeitos dos fármacos , Quinases Associadas a rho/metabolismo
13.
Exp Neurol ; 247: 438-46, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23337773

RESUMO

The Rho/Rho-kinase signaling pathway has been shown to be involved in the complications of diabetes. In this study, we found that fasudil, a specific Rho-kinase inhibitor, had a beneficial effect on the motor nerve conduction velocity (MNCV), which is delayed in rats with streptozotocin (STZ)-induced diabetes. Cadherin-dependent adherens junctions (AJs) in myelinating Schwann cells, necessary for proper myelin formation and rapid propagation of action potentials, are regulated by Rho/Rho-kinase signaling. These AJ structures are maintained by E-cadherin and catenin complexes such as ß-catenin and p120 catenin. To elucidate the mechanism underlying the effect of fasudil on MNCV, we examined alterations in AJ structure in the peripheral nerves of the experimental rats. Our results showed that the activities of Rho and Rho-kinase increased simultaneously in the sciatic nerves of the diabetic rats. Fasudil restored the MNCV by suppressing the up-regulation of the Rho-kinase. In the diabetic state, enhanced Rho and Rho-kinase activity reduced p120 catenin expression and altered the distribution of p120 catenin and E-cadherin, which are normally localized in the paranodal compartment of the nodes of Ranvier and Schmidt-Lanterman incisures where autotypic AJs stabilize myelin structure. Fasudil restored normal p120 catenin expression and the distribution of p120 catenin and E-cadherin in the myelin sheath. In conclusion, reduced expression and altered distribution of the adhesion molecules in the myelin sheath might contribute to the slowing of the MNCV in the diabetic rats. Fasudil, through its effect on the distribution of the adhesion-related molecules, might prevent slowing of the MNCV.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Caderinas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Condução Nervosa/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Células de Schwann/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Cateninas/metabolismo , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Estimulação Elétrica , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Proteínas do Tecido Nervoso/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Ratos , Ratos Sprague-Dawley , Fator Rho/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiopatologia , beta Catenina/metabolismo , Quinases Associadas a rho/metabolismo , delta Catenina
14.
PLoS One ; 7(12): e51171, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226566

RESUMO

BACKGROUND: We aimed to examine associations among serum 25-hydroxyvitamin D (25OHD) levels, 1,25-dihyroxyvitamin D (1,25OHD) levels, vitamin D receptor (VDR) polymorphisms, and renal function based on estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes. METHODS: In a cross-sectional study of 410 patients, chronic kidney disease (CKD) stage assessed by eGFR was compared with 25OHD, 1,25OHD, and VDR FokI (rs10735810) polymorphisms by an ordered logistic regression model adjusted for the following confounders: disease duration, calendar month, use of angiotensin converting enzyme inhibitors/angiotensin receptor blockers or statins, and serum calcium, phosphate, and intact parathyroid hormone levels. RESULTS: 1,25OHD levels, rather than 25OHD levels, showed seasonal oscillations; peak levels were seen from May to October and the lowest levels were seen from December to February. These findings were evident in patients with CKD stage 3 ~ 5 but not stage 1 ~ 2. eGFR was in direct proportion to both 25OHD and 1,25OHD levels (P<0.0001), but it had stronger linearity with 1,25OHD (r = 0.73) than 25OHD (r = 0.22) levels. Using multivariate analysis, 1,25OHD levels (P<0.001), but not 25OHD levels, were negatively associated with CKD stage. Although FokI polymorphisms by themselves showed no significant associations with CKD stage, a significant interaction between 1,25OHD and FokITT was observed (P = 0.008). The positive association between 1,25OHD and eGFR was steeper in FokICT and CC polymorphisms (r = 0.74) than FokITT polymorphisms (r = 0.65). CONCLUSIONS: These results suggest that higher 1,25OHD levels may be associated with better CKD stages in patients with type 2 diabetes and that this association was modified by FokI polymorphisms.


Assuntos
Desoxirribonucleases de Sítio Específico do Tipo II/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Testes de Função Renal , Polimorfismo Genético , Receptores de Calcitriol/genética , Vitamina D/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/sangue , Feminino , Predisposição Genética para Doença , Taxa de Filtração Glomerular , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/genética , Falência Renal Crônica/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estações do Ano , Vitamina D/análogos & derivados , Adulto Jovem
15.
Biochem Biophys Res Commun ; 411(4): 798-803, 2011 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-21787749

RESUMO

Thrombin has been shown to increase expression of chemokines such as monocyte chemoattractant protein 1 (MCP-1) in endothelial cells, leading to the development of atherosclerosis. However, the precise mechanism of this induction remains unknown. In the present study, we investigated whether the small G protein RhoA, and its effector, Rho-kinase are involved in MCP-1 induction by thrombin in endothelial cells. Y-27632, a specific Rho-kinase inhibitor, potently inhibited MCP-1 induction by thrombin. Y-27632 significantly decreased the chemotactic activity of thrombin-stimulated supernatants of endothelial cells on monocytes. Importantly, fasudil, a specific Rho-kinase inhibitor, attenuated MCP-1 gene expression in the aorta of db/db mice. Y-27632 attenuated thrombin-mediated phosphorylation of p38MAPK and p65, indicating that Rho-kinase mediates thrombin-induced MCP-1 expression through p38MAPK and NF-κB activation. Our findings demonstrate that the Rho/Rho-kinase signaling pathway plays a critical role in thrombin-mediated MCP-1 expression and function, and suggest that Rho/Rho-kinase may be an important target in the development of new therapeutic strategies for atherosclerosis.


Assuntos
Quimiocina CCL2/biossíntese , Endotélio Vascular/metabolismo , NF-kappa B/metabolismo , Trombina/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases Associadas a rho/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Amidas/farmacologia , Animais , Aorta/metabolismo , Movimento Celular , Células Cultivadas , Quimiocina CCL2/genética , Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos , Monócitos/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Trombina/genética , Quinases Associadas a rho/antagonistas & inibidores
16.
Biochem Biophys Res Commun ; 402(4): 725-30, 2010 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-20977889

RESUMO

Macrophage accumulation has been implicated in the pathogenesis of inflammatory glomerular disease. Monocyte chemoattractant protein-1 (MCP-1) plays a central role in recruiting monocytes to the glomeruli. Tumor necrosis factor-α (TNF-α) has been shown to induce MCP-1 expression in mesangial cells, although the precise mechanisms remain unclear. We previously demonstrated that RhoA and its effector, Rho-kinase (Rho-associated coiled-coil containing protein kinase, ROCK), are involved in the pathogenesis of diabetic nephropathy. However, its role in MCP-1 induction by TNF-α has not been elucidated. In the present study, we investigated whether the Rho/Rho-kinase signaling pathway regulates the TNF-α-mediated induction of MCP-1 in mesangial cells. Exposure of mouse mesangial cells (MES-13) to TNF-α resulted in an increase of MCP-1 expression (by RT-PCR) and secretion into the medium (by ELISA). Pull down and Western blot analysis revealed that TNF-α activated RhoA and Rho-kinase. Based on these observations, we speculated that the Rho/Rho-kinase signaling pathway may be involved in MCP-1 induction by TNF-α. In agreement with this concept, Y-27632, a specific Rho-kinase inhibitor, attenuated TNF-α-mediated induction of MCP-1. We demonstrated that Y-27632 inhibited TNF-α-mediated monocyte migration and attenuated TNF-α-mediated p38 MAPK activation. Based on these data we infer that Y-27632 inhibits TNF-α-induced MCP-1 expression, secretion and function through inhibition of Rho-kinase and p38 MAPK activity. Our study suggests that Rho/Rho-kinase is an important therapeutic target of monocyte recruitment and accumulation within the glomerulus in inflammatory renal disease.


Assuntos
Quimiocina CCL2/metabolismo , Células Mesangiais/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases Associadas a rho/metabolismo , Amidas/farmacologia , Animais , Linhagem Celular , Quimiotaxia , Inibidores Enzimáticos/farmacologia , Glomerulonefrite/metabolismo , Células Mesangiais/efeitos dos fármacos , Camundongos , Piridinas/farmacologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/fisiologia , Quinases Associadas a rho/antagonistas & inibidores
17.
Intern Med ; 48(18): 1621-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19755764

RESUMO

OBJECTIVE: To investigate the relationship between homeostasis model assessment for insulin resistance (HOMA-R) and urinary albumin excretion in Japanese and clarify gender difference in albuminuria-related insulin resistance. METHODS: The subject group consisted of 752 Japanese who had no history of diabetes, hypertension or dyslipidemia. After anthropometric examination, fasting blood samples were obtained to determine plasma glucose (FPG), lipids and HOMA-R. The urinary excretion of albumin in the first void urine was expressed as the creatinine ratio (ACR, mg/gCr). Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine using the formula for Japanese. RESULTS: HOMA-R showed a significant correlation with ACR, and the correlation between HOMA-R and ACR was evident in the subjects with central obesity, whereas no significant correlation was found in the non-obese subjects. There was no correlation between HOMA-R and eGFR. HOMA-R increased according to the quintile of ACR and followed a significant trend. This association was obvious in males; however, in females there was no significant trend. Multiple regression analysis revealed that HOMA-R showed a significant correlation with age, waist circumference, blood pressure and serum triglyceride. In addition, ACR exhibited an independent association with HOMA-R. The association of HOMA-R and ACR was observed only in males, and was not present in females. CONCLUSION: Microalbuminuria is associated with insulin resistance in Japanese, where central obesity might play an essential role. This association is gender-specific suggesting the involvement of sex hormones in the pathogenesis of albuminuria-related insulin resistance.


Assuntos
Albuminúria/fisiopatologia , Resistência à Insulina/fisiologia , Adulto , Povo Asiático , Glicemia/metabolismo , Creatinina/sangue , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/fisiopatologia , Feminino , Taxa de Filtração Glomerular , Homeostase , Humanos , Japão , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Obesidade Abdominal/fisiopatologia , Fatores de Risco , Caracteres Sexuais
18.
J Atheroscler Thromb ; 16(3): 250-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19556726

RESUMO

AIM: Menopause is a risk factor for cardiovascular disease (CVD) in women because of the reduction in endogenous estrogen. Recently, single nucleotide polymorphisms (SNPs) of the estrogen receptor alpha (ESR-1) gene (c.454-397T>C) associated with the prognosis of myocardial infarction in postmenopausal women were identified; however, the mechanism by which genetic variation of ESR-1 contributes to the pathogenesis of CVD is unknown. Circulating levels of adipokines and inflammatory cytokines predict CVD risk; hence, this study aimed to investigate whether ESR-1 genotypes (c.454-397T>C) might influence circulating levels of adipokines and inflammatory cytokines in postmenopausal women with type 2 diabetes. METHODS: Sixty-three postmenopausal women with type 2 diabetes were recruited. Serum levels of adiponectin, resistin, interleukin-6 (IL-6), and high-sensitive C-reactive protein (hs-CRP) were determined. RESULTS: The genotype of ESR-1 was closely associated with serum adiponectin, which was decreased in subjects with the T allele and was lowest in those with the T/T genotype. Multiple logistic regression analysis revealed independent contribution of the homozygote for the T allele to low serum levels of adiponectin. CONCLUSION: The T allele of the c.454-397T>C SNP of ESR-1 is associated with low serum levels of adiponectin, which may lead to a high risk of CVD in postmenopausal women.


Assuntos
Adiponectina/sangue , Diabetes Mellitus Tipo 2/genética , Receptor alfa de Estrogênio/genética , Polimorfismo de Nucleotídeo Único , Pós-Menopausa , Idoso , Alelos , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/sangue , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco
19.
Eur J Pharmacol ; 568(1-3): 242-7, 2007 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-17511984

RESUMO

This study aimed to investigate the effect of the Rho-kinase inhibitor fasudil on the development of diabetic nephropathy and clarify a contribution of the Rho/Rho-kinase pathway to the pathogenesis of diabetic nephropathy. Diabetes was induced in male Sprague-Dawley rats with an intraperitoneal injection of streptozotocin. Animals were then divided into the following 4 groups; normal control rats, diabetic rats, diabetic rats administered fasudil orally and diabetic rats administered fluvastatin (3-hydroxy-methylglutaryl coenzyme A reductase inhibitor, statin) orally. After 1 month of treatment, neither fasudil nor statin had any influence on blood glucose or blood pressure in diabetic rats. While urinary excretion of albumin and 8-hydroxydeoxyguanosine (8-OHdG) was increased in diabetic rats, both of these increases were abolished by fasudil and statin. Rho activity was enhanced in the renal cortex of diabetic rats compared to normal controls, and this enhancement was abolished by statin treatment. Expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) mRNA was up-regulated in the renal cortex of diabetic rats, and this was abolished by fasudil as well as statin. Expression of NOX4 mRNA (catalytic subunit of NAD(P)H oxidase) was up-regulated in the renal cortex of diabetic rats, an effect which was also abolished by fasudil as well as statin. The present study demonstrates that the Rho/Rho-kinase pathway is involved in up-regulation of TGF-beta, CTGF and NAD(P)H oxidase in diabetic kidney. We conclude that suppression of the Rho/Rho-kinase pathway could be a new strategy for the treatment of diabetic nephropathy.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Albuminúria/tratamento farmacológico , Albuminúria/metabolismo , Animais , Glicemia/análise , Pressão Sanguínea/efeitos dos fármacos , Colesterol/sangue , Fator de Crescimento do Tecido Conjuntivo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Ácidos Graxos Monoinsaturados/uso terapêutico , Fluvastatina , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Proteínas Imediatamente Precoces/genética , Indóis/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular/genética , Córtex Renal/efeitos dos fármacos , Córtex Renal/metabolismo , Masculino , NADPH Oxidase 4 , NADPH Oxidases/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Estreptozocina , Fator de Crescimento Transformador beta/genética , Quinases Associadas a rho
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