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1.
Indian J Med Res ; 157(5): 470-476, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37955221

RESUMO

Background & objectives: Diabetes mellitus (DM) is characterized by increase in blood glucose levels due to defective insulin secretion or insulin sensitivity. Interleukins (ILs) are known to play an important role in the pathogenesis of DM. The aim of this study was to investigate the serum concentration of IL-33 and its receptor soluble ST2 (sST2) in patients with diabetes and draw a correlation between their serum levels and different standard glycaemic indices of patients affected with type-2 diabetes with or without metabolic syndrome. Methods: Thirty type-2 diabetic individuals and 30 healthy controls were recruited for this study. Serum and plasma were separated by centrifugation of blood for quantitative measurement of IL-33, sST2 and other biochemical parameters. Results: It was observed that serum IL-33 levels were significantly less and sST2 levels were significantly high in type-2 diabetic individuals as compared to healthy controls. A significant correlation between the serum IL-33 concentration and fasting plasma glucose (FPG) and postprandial plasma glucose (PPG) levels were also found. Additionally, data also elucidated that serum levels of high-density lipoprotein, low-density lipoprotein or triglyceride in type-2 diabetics did not influence the serum levels of IL-33 and sST2, thereby excluding these factors as the major drivers of changes in serum IL-33 and sST2 concentration. Interpretation & conclusions: This study demonstrated alteration in serum levels of IL-33 and sST2 in type-2 diabetic individuals. Further mechanistic studies, focusing on the progression of type-2 diabetes could elucidate the involvement of IL-33 in the cellular acquisition of insulin resistance as observed in type-2 diabetics.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Humanos , Interleucina-33 , Síndrome Metabólica/complicações , Glicemia/metabolismo , Interleucinas , Diabetes Mellitus Tipo 2/complicações
2.
J Cell Physiol ; 237(1): 992-1012, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34520565

RESUMO

Histone protein modifications control the inflammatory state of many immune cells. However, how dynamic alteration in histone methylation causes endothelial inflammation and apoptosis is not clearly understood. To examine this, we explored two contrasting histone methylations; an activating histone H3 lysine 4 trimethylation (H3K4me3) and a repressive histone H3 lysine 27 trimethylation (H3K27me3) in endothelial cells (EC) undergoing inflammation. Through computer-aided reconstruction and 3D printing of the human coronary artery, we developed a unique model where EC were exposed to a pattern of oscillatory/disturbed flow as similar to in vivo conditions. Upon induction of endothelial inflammation, we detected a significant rise in H3K4me3 caused by an increase in the expression of SET1/COMPASS family of H3K4 methyltransferases, including MLL1, MLL2, and SET1B. In contrast, EC undergoing inflammation exhibited truncated H3K27me3 level engendered by EZH2 cytosolic translocation through threonine 367 phosphorylation and an increase in the expression of histone demethylating enzyme JMJD3 and UTX. Additionally, many SET1/COMPASS family of proteins, including MLL1 (C), MLL2, and WDR5, were associated with either UTX or JMJD3 or both and such association was elevated in EC upon exposure to inflammatory stimuli. Dynamic enrichment of H3K4me3 and loss of H3K27me3 at Notch-associated gene promoters caused ADAM17 and Jagged-1 derepression and abrupt Notch activation. Conversely, either reducing H3K4me3 or increasing H3K27me3 in EC undergoing inflammation attenuated Notch activation, endothelial inflammation, and apoptosis. Together, these findings indicate that dynamic chromatin modifications may cause an inflammatory and apoptotic switch of EC and that epigenetic reprogramming can potentially improve outcomes in endothelial inflammation-associated cardiovascular diseases.


Assuntos
Histonas , Lisina , Proteína ADAM17/metabolismo , Células Endoteliais/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Inflamação/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Lisina/metabolismo
3.
Bioinformatics ; 35(10): 1701-1711, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30307528

RESUMO

MOTIVATION: Traditional cancer therapy is focused on eradicating fast proliferating population of tumor cells. However, existing evidences suggest survival of sub-population of cancer cells that can resist chemotherapy by entering a 'persister' state of minimal growth. These cells eventually survive to produce cells resistant to drugs. The identifying of appropriate targets that can eliminate the drug-tolerant 'persisters' remains a challenge. Hence, a deeper understanding of the distinctive genetic signatures that lead to resistance is of utmost importance to design an appropriate therapy. RESULTS: In this study, deep-sequencing of mRNA was performed in osteosarcoma (OS) cells, exposed to the widely used drug, cisplatin which is an integral part of current treatment regime for OS. Transcriptomic analysis was performed in (i) untreated OS; (ii) persister sub-population of cells post-drug shock; (iii) cells which evade growth bottleneck and (iv) drug-resistant cells obtained after several rounds of drug shock and revival. The transcriptomic signatures and pathways regulated in each group were compared; the transcriptomic pipeline to the acquisition of resistance was analyzed and the core network of genes altered during the process was delineated. Additionally, our transcriptomic data were compared with OS patient data obtained from Gene Ontology Omnibus. We observed a sub-set of genes to be commonly expressed in both data sets with a high correlation (0.81) in expression pattern. To the best of our knowledge, this study is uniquely designed to understand the series of genetic changes leading to the emergence of drug-resistant cells, and implications from this study have a potential therapeutic impact. AVAILABILITY AND IMPLEMENTATION: All raw data can be accessed from GEO database (https://www.ncbi.nlm.nih.gov/geo/) under the GEO accession number GSE86053. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Humanos , Transcriptoma
4.
Diabetologia ; 62(11): 2129-2142, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31399844

RESUMO

AIMS/HYPOTHESIS: Long non-coding RNAs (lncRNAs) are garnering increasing attention for their putative roles in the pathogenesis of chronic diseases, including diabetic kidney disease (DKD). However, much about in vivo lncRNA functionality in the adult organism remains unclear. To better understand lncRNA regulation and function in DKD, we explored the effects of the modular scaffold lncRNA HOTAIR (HOX antisense intergenic RNA), which approximates chromatin modifying complexes to their target sites on the genome. METHODS: Experiments were performed in human kidney tissue, in mice with streptozotocin-induced diabetes, the db/db mouse model of type 2 diabetes, podocyte-specific Hotair knockout mice and conditionally immortalised mouse podocytes. RESULTS: HOTAIR was observed to be expressed by several kidney cell-types, including glomerular podocytes, in both human and mouse kidneys. However, knockout of Hotair from podocytes had almost no effect on kidney structure, function or ultrastructure. Glomerular HOTAIR expression was found to be increased in human DKD, in the kidneys of mice with streptozotocin-induced diabetes and in the kidneys of db/db mice. Likewise, exposure of cultured mouse podocytes to high glucose caused upregulation of Hotair expression, which occurred in a p65-dependent manner. Although HOTAIR expression was upregulated in DKD and in high glucose-exposed podocytes, its knockout did not alter the development of kidney damage in diabetic mice. Rather, in a bioinformatic analysis of human kidney tissue, HOTAIR expression closely paralleled the expression of its genic neighbour, HOXC11, which is important to developmental patterning but which has an uncertain role in the adult kidney. CONCLUSIONS/INTERPRETATION: Many lncRNAs have been found to bind to the same chromatin modifying complexes. Thus, there is likely to exist sufficient redundancy in the system that the biological effects of dysregulated lncRNAs in kidney disease may often be inconsequential. The example of the archetypal scaffold lncRNA, HOTAIR, illustrates how lncRNA dysregulation may be a bystander in DKD without necessarily contributing to the pathogenesis of the condition. In the absence of in vivo validation, caution should be taken before ascribing major functional roles to single lncRNAs in the pathogenesis of chronic diseases.


Assuntos
Nefropatias Diabéticas/metabolismo , Regulação da Expressão Gênica , RNA Longo não Codificante/metabolismo , Animais , Padronização Corporal , Cromatina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Hibridização In Situ , Glomérulos Renais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Podócitos/citologia , Podócitos/metabolismo , RNA Longo não Codificante/genética
5.
BMC Cancer ; 19(1): 1045, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690262

RESUMO

BACKGROUND: Resistance to chemotherapy is one of the major hurdles in current cancer therapy. With the increasing occurrence of drug resistance, a paradigm shift in treatment strategy is required. Recently "medication vacation" has emerged as a unique, yet uncomplicated strategy in which withdrawal of drug pressure for certain duration allowed tumor cells to regain sensitivity to the drug. However, little is known about the molecular alterations associated with such an outcome. METHODS: In this study, human osteosarcoma (OS) cells resistant to the extensively used drug cisplatin, were withdrawn from drug pressure, and thereafter cytotoxic response of the cells to the drug was evaluated. We further performed next-generation RNA sequencing and compared transcriptome between parental (OS), resistant (OS-R) and the drug withdrawn (OS-DW) cells. Differentially expressed transcripts were identified, and biological association network (BAN), gene ontology (GO) and pathway enrichment analysis of the differentially regulated transcripts were performed to identify key events associated with withdrawal of drug pressure. RESULTS: Following drug withdrawal, the sensitivity of the cells to the drug was found to be regained. Analysis of the expression profile showed that key genes like, IRAK3, IL6ST, RELA, AKT1, FKBP1A and ADIPOQ went significantly down in OS-DW cells when compared to OS-R. Also, genes involved in Wnt signaling, PI3K-Akt, Notch signaling, and ABC transporters were drastically down-regulated in OS-DW cells compared to OS-R. Although, a very small subset of genes maintained similar expression pattern between OS, OS-R and OS-DW, nonetheless majority of the transcriptomic pattern of OS-DW was distinctively different and unique in comparison to either the drug sensitive OS or drug resistant OS-R cells. CONCLUSION: Our data suggests that though drug withdrawal causes reversal of sensitivity, the transcriptomic pattern does not necessarily show significant match with resistant or parental control cells. We strongly believe that exploration of the molecular basis of drug holiday might facilitate additional potential alternative treatment options for aggressive and resistant cancers.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Osteossarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Receptor gp130 de Citocina/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Análise de Sequência de RNA , Fator de Transcrição RelA/genética , Suspensão de Tratamento
6.
Int J Mol Sci ; 20(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866404

RESUMO

Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) plays crucial roles in cardiac homeostasis. Adult cardiomyocyte specific overexpression of eNOS confers protection against myocardial-reperfusion injury. However, the global effects of NO overexpression in developing cardiovascular system is still unclear. We hypothesized that nitric oxide overexpression affects the early migration of cardiac progenitor cells, vasculogenesis and function in a chick embryo. Vehicle or nitric oxide donor DEAN (500 mM) were loaded exogenously through a small window on the broad side of freshly laid egg and embryonic development tracked by live video-microscopy. At Hamburg Hamilton (HH) stage 8, the cardiac progenitor cells (CPC) were isolated and cell migration analysed by Boyden Chamber. The vascular bed structure and heart beats were compared between vehicle and DEAN treated embryos. Finally, expression of developmental markers such as BMP4, Shh, Pitx2, Noggin were measured using reverse transcriptase PCR and in-situ hybridization. The results unexpectedly showed that exogenous addition of pharmacological NO between HH stage 7⁻8 resulted in embryos with situs inversus in 28 out of 100 embryos tested. Embryos treated with NO inhibitor cPTIO did not have situs inversus, however 10 embryos treated with L-arginine showed a situs inversus phenotype. N-acetyl cysteine addition in the presence of NO failed to rescue situs inversus phenotype. The heart beat is normal (120 beats/min) although the vascular bed pattern is altered. Migration of CPCs in DEAN treated embryos is reduced by 60% compared to vehicle. BMP4 protein expression increases on the left side of the embryo compared to vehicle control. The data suggests that the NO levels in the yolk are important in turning of the heart during embryonic development. High levels of NO may lead to situs inversus condition in avian embryo by impairing cardiac progenitor cell migration through the NO-BMP4-cGMP axis.


Assuntos
Proteína Morfogenética Óssea 4/genética , Coração/fisiologia , Miócitos Cardíacos/citologia , Óxido Nítrico/farmacologia , Situs Inversus/induzido quimicamente , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Desenvolvimento Embrionário , Coração/efeitos dos fármacos , Testes de Função Cardíaca/efeitos dos fármacos , Microscopia de Vídeo , Miócitos Cardíacos/efeitos dos fármacos , Situs Inversus/genética , Regulação para Cima
7.
Am J Physiol Renal Physiol ; 314(3): F412-F422, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29141939

RESUMO

Focal segmental glomerulosclerosis (FSGS) is an important cause of nondiabetic chronic kidney disease (CKD). Sodium-glucose cotransporter 2 inhibition (SGLT2i) therapy attenuates the progression of diabetic nephropathy, but it remains unclear whether SGLT2i provides renoprotection in nondiabetic CKD such as FSGS. The primary aim of this pilot study was to determine the effect of 8 wk of dapagliflozin on glomerular filtration rate (GFR) in humans and in experimental FSGS. Secondary end points were related to changes in renal hemodynamic function, proteinuria, and blood pressure (BP). GFR (inulin) and renal plasma flow (para-aminohippurate), proteinuria, and BP were measured in patients with FSGS ( n = 10), and similar parameters were measured in subtotally nephrectomized (SNx) rats. In response to dapagliflozin, changes in GFR, renal plasma flow, and 24-h urine protein excretion were not statistically significant in humans or rats. Systolic BP (SBP) decreased in SNx rats (196 ± 26 vs. 165 ± 33 mmHg; P < 0.001), whereas changes were not statistically significant in humans (SBP 112.7 ± 8.5 to 112.8 ± 11.2 mmHg, diastolic BP 71.8 ± 6.5 to 69.6 ± 8.4 mmHg; P = not significant), although hematocrit increased (0.40 ± 0.05 to 0.42 ± 0.05%; P = 0.03). In archival kidney tissue from a separate patient cohort, renal parenchymal SGLT2 mRNA expression was decreased in individuals with FSGS compared with controls. Short-term treatment with the SGLT2i dapagliflozin did not modify renal hemodynamic function or attenuate proteinuria in humans or in experimental FSGS. This may be related to downregulation of renal SGLT2 expression. Studies examining the impact of SGLT2i on markers of kidney disease in patients with other causes of nondiabetic CKD are needed.


Assuntos
Arteríolas/efeitos dos fármacos , Compostos Benzidrílicos/uso terapêutico , Taxa de Filtração Glomerular/efeitos dos fármacos , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Glucosídeos/uso terapêutico , Rim/irrigação sanguínea , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Vasoconstrição/efeitos dos fármacos , Adulto , Animais , Arteríolas/metabolismo , Arteríolas/fisiopatologia , Modelos Animais de Doenças , Feminino , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudo de Prova de Conceito , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , Proteinúria/fisiopatologia , Ratos Sprague-Dawley , Transportador 2 de Glucose-Sódio/genética , Transportador 2 de Glucose-Sódio/metabolismo , Fatores de Tempo , Resultado do Tratamento
8.
J Am Soc Nephrol ; 28(9): 2641-2653, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28424277

RESUMO

The nonreceptor kinase Janus kinase 2 (JAK2) has garnered attention as a promising therapeutic target for the treatment of CKD. However, being ubiquitously expressed in the adult, JAK2 is also likely to be necessary for normal organ function. Here, we investigated the phenotypic effects of JAK2 deficiency. Mice in which JAK2 had been deleted from podocytes exhibited an elevation in urine albumin excretion that was accompanied by increased podocyte autophagosome fractional volume and p62 aggregation, which are indicative of impaired autophagy completion. In cultured podocytes, knockdown of JAK2 similarly impaired autophagy and led to downregulation in the expression of lysosomal genes and decreased activity of the lysosomal enzyme, cathepsin D. Because transcription factor EB (TFEB) has recently emerged as a master regulator of autophagosome-lysosome function, controlling the expression of several of the genes downregulated by JAK2 knockdown, we questioned whether TFEB is regulated by JAK2. In immortalized mouse podocytes, JAK2 knockdown decreased TFEB promoter activity, expression, and nuclear localization. In silico analysis and chromatin immunoprecipitation assays revealed that the downstream mediator of JAK2 signaling STAT1 binds to the TFEB promoter. Finally, overexpression of TFEB in JAK2-deficient podocytes reversed lysosomal dysfunction and restored albumin permselectivity. Collectively, these observations highlight the homeostatic actions of JAK2 in podocytes and the importance of TFEB to autophagosome-lysosome function in these cells. These results also raise the possibility that therapeutically modulating TFEB activity may improve podocyte health in glomerular disease.


Assuntos
Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Janus Quinase 2/genética , Podócitos/metabolismo , Albuminúria/genética , Animais , Autofagossomos/ultraestrutura , Catepsina D/metabolismo , Células Cultivadas , Simulação por Computador , Regulação para Baixo , Técnicas de Silenciamento de Genes , Janus Quinase 2/deficiência , Janus Quinase 2/metabolismo , Glomérulos Renais/citologia , Lisossomos/ultraestrutura , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Peptídeos/metabolismo , Fenótipo , Podócitos/ultraestrutura , RNA Mensageiro/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo
9.
Biochem Cell Biol ; 95(2): 263-272, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28177770

RESUMO

Liver fibrosis is now well recognized as the causative factor for increased mortality from complications associated with liver pathologies. Activated hepatic stellate cells (HSCs) play a critical role in the progression of liver fibrosis. Therefore, targeting these activated HSCs to prevent and (or) treat liver disease is a worthwhile approach to explore. In the present in vitro study, we investigated the use of bipotential murine oval liver cells (BMOL) in regulating the functions of activated HSCs to prevent progression of liver fibrosis. We used a conditioned medium-based approach to study the effect of BMOL cells on activated HSC survival and function. Our data showed that BMOL cells block the contraction of activated HSCs by inducing apoptosis of these cells. We demonstrated that BMOL cells secrete soluble factors, such as interleukin-6 (IL-6), which induced apoptosis of activated HSCs. Using both pharmacological and molecular inhibitor approaches, we further identified that IL-6-mediated activation of NF-κB-iNOS-NO-ROS signaling in activated HSCs plays a critical role in BMOL-cell-mediated apoptosis of activated HSCs. Thus, the present study provides an alternative cell-based therapeutic approach to treat liver fibrosis.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Interleucina-6/farmacologia , NF-kappa B/genética , Óxido Nítrico Sintase Tipo II/genética , Células-Tronco/metabolismo , Amidinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Arsenicais/farmacologia , Benzilaminas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Transformada , Células Cultivadas , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Regulação da Expressão Gênica , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Imidazóis/farmacologia , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos , Modelos Biológicos , NF-kappa B/agonistas , NF-kappa B/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Quinoxalinas/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
10.
J Am Soc Nephrol ; 27(10): 3117-3128, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26961347

RESUMO

Like many organs, the kidney stiffens after injury, a process that is increasingly recognized as an important driver of fibrogenesis. Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are related mechanosensory proteins that bind to Smad transcription factors, the canonical mediators of profibrotic TGF-ß responses. Here, we investigated the role of YAP/TAZ in the matrix stiffness dependence of fibroblast responses to TGF-ß In contrast to growth on a stiff surface, fibroblast growth on a soft matrix led to YAP/TAZ sequestration in the cytosol and impaired TGF-ß-induced Smad2/3 nuclear accumulation and transcriptional activity. YAP knockdown or treatment with verteporfin, a drug that was recently identified as a potent YAP inhibitor, elicited similar changes. Furthermore, verteporfin reduced YAP/TAZ levels and decreased the total cellular levels of Smad2/3 after TGF-ß stimulation. Verteporfin treatment of mice subjected to unilateral ureteral obstruction similarly reduced YAP/TAZ levels and nuclear Smad accumulation in the kidney, and attenuated renal fibrosis. Our data suggest that organ stiffening cooperates with TGF-ß to induce fibrosis in a YAP/TAZ- and Smad2/3-dependent manner. Interference with this YAP/TAZ and TGF-ß/Smad crosstalk likely underlies the antifibrotic activity of verteporfin. Finally, through repurposing of a clinically used drug, we illustrate the therapeutic potential of a novel mechanointerference strategy that blocks TGF-ß signaling and renal fibrogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Rim/patologia , Fosfoproteínas/fisiologia , Proteína Smad2/fisiologia , Proteína Smad3/fisiologia , Fatores de Transcrição/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Aciltransferases , Animais , Proteínas de Ciclo Celular , Fibrose/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Proteínas de Sinalização YAP
11.
J Am Soc Nephrol ; 27(7): 2021-34, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26534922

RESUMO

Epigenetic regulation of oxidative stress is emerging as a critical mediator of diabetic nephropathy. In diabetes, oxidative damage occurs when there is an imbalance between reactive oxygen species generation and enzymatic antioxidant repair. Here, we investigated the function of the histone methyltransferase enzyme enhancer of zeste homolog 2 (EZH2) in attenuating oxidative injury in podocytes, focusing on its regulation of the endogenous antioxidant inhibitor thioredoxin interacting protein (TxnIP). Pharmacologic or genetic depletion of EZH2 augmented TxnIP expression and oxidative stress in podocytes cultured under high-glucose conditions. Conversely, EZH2 upregulation through inhibition of its regulatory microRNA, microRNA-101, downregulated TxnIP and attenuated oxidative stress. In diabetic rats, depletion of EZH2 decreased histone 3 lysine 27 trimethylation (H3K27me3), increased glomerular TxnIP expression, induced podocyte injury, and augmented oxidative stress and proteinuria. Chromatin immunoprecipitation sequencing revealed H3K27me3 enrichment at the promoter of the transcription factor Pax6, which was upregulated on EZH2 depletion and bound to the TxnIP promoter, controlling expression of its gene product. In high glucose-exposed podocytes and the kidneys of diabetic rats, the lower EZH2 expression detected coincided with upregulation of Pax6 and TxnIP. Finally, in a gene expression array, TxnIP was among seven of 30,854 genes upregulated by high glucose, EZH2 depletion, and the combination thereof. Thus, EZH2 represses the transcription factor Pax6, which controls expression of the antioxidant inhibitor TxnIP, and in diabetes, downregulation of EZH2 promotes oxidative stress. These findings expand the extent to which epigenetic processes affect the diabetic kidney to include antioxidant repair.


Assuntos
Nefropatias Diabéticas/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/fisiologia , Estresse Oxidativo , Podócitos/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Regulação para Cima
12.
Arterioscler Thromb Vasc Biol ; 34(2): 419-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24265417

RESUMO

OBJECTIVE: Recent evidence suggests G-protein-coupled receptor-2-interacting protein-1 (GIT1) overexpression in several human metastatic tumors, including breast, lung, and prostate. Tumor metastasis is associated with an increase in angiogenesis. We have showed previously that GIT1 is required for postnatal angiogenesis during lung development. However, the functional role of GIT1 in pathological angiogenesis during tumor growth is unknown. APPROACH AND RESULTS: In the present study, we show inhibition of angiogenesis in matrigel implants as well as reduced tumor angiogenesis and melanoma tumor growth in GIT1-knockout mice. We demonstrate that this is a result of impaired directional migration of GIT1-depleted endothelial cells toward a vascular endothelial growth factor gradient. Cortactin-mediated lamellipodia formation in the leading edge is critical for directional migration. We observed a significant reduction in cortactin localization and lamellipodia formation in the leading edge of GIT1-depleted endothelial cells. We specifically identified that the Spa homology domain (aa 250-420) of GIT1 is required for GIT1-cortactin complex localization to the leading edge. The mechanisms involved extracellular signal-regulated kinases 1 and 2-mediated Cortactin-S405 phosphorylation and activation of Rac1/Cdc42. Finally, using gain of function studies, we show that a constitutively active mutant of cortactin restored directional migration of GIT1-depleted cells. CONCLUSION: Our data demonstrated that a GIT1-cortactin association through GIT1-Spa homology domain is required for cortactin localization to the leading edge and is essential for endothelial cell directional migration and tumor angiogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Movimento Celular , Cortactina/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Melanoma Experimental/metabolismo , Neovascularização Patológica , Neovascularização Fisiológica , Pseudópodes/metabolismo , Neoplasias de Tecidos Moles/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Cortactina/genética , Proteínas Ativadoras de GTPase/deficiência , Proteínas Ativadoras de GTPase/genética , Células HEK293 , Humanos , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Transdução de Sinais , Neoplasias de Tecidos Moles/irrigação sanguínea , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia , Fatores de Tempo , Transfecção , Carga Tumoral , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
13.
Clin Sci (Lond) ; 126(11): 775-84, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24283268

RESUMO

Progression of liver fibrosis to HCC (hepatocellular carcinoma) is a very complex process which involves several pathological phenomena, including hepatic stellate cell activation, inflammation, fibrosis and angiogenesis. Therefore inhibiting multiple pathological processes using a single drug can be an effective choice to curb the progression of HCC. In the present study, we used the mTOR inhibitor everolimus to observe its effect on the in vitro activation of hepatic stellate cells and angiogenesis. The results of the present study demonstrated that everolimus treatment blocked the functions of the immortalized human activated hepatic stellate cell line LX-2 without affecting the viability and migration of primary human stellate cells. We also observed that treatment with everolimus (20 nM) inhibited collagen production by activated stellate cells, as well as cell contraction. Everolimus treatment was also able to attenuate the activation of primary stellate cells to their activated form. Angiogenesis studies showed that everolimus blocked angiogenesis in a rat aortic ring assay and inhibited the tube formation and migration of liver sinusoidal endothelial cells. Finally, everolimus treatment reduced the load of tumoral myofibroblasts in a rat model of HCC. These data suggest that everolimus targets multiple mechanisms, making it a potent blocker of the progression of HCC from liver fibrosis.


Assuntos
Inibidores da Angiogênese/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Imunossupressores/farmacologia , Sirolimo/análogos & derivados , Actinas/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Colágeno/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Everolimo , Humanos , Fígado/efeitos dos fármacos , Cirrose Hepática/patologia , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Músculo Liso/metabolismo , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Transplante de Neoplasias , Neovascularização Patológica , Ratos , Ratos Wistar , Sirolimo/farmacologia
14.
Nitric Oxide ; 43: 45-54, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25196952

RESUMO

Rho GTPases are a globular, monomeric group of small signaling G-protein molecules. Rho-associated protein kinase/Rho-kinase (ROCK) is a downstream effector protein of the Rho GTPase. Rho-kinases are the potential therapeutic targets in the treatment of cardiovascular diseases. Here, we have primarily discussed the intriguing roles of ROCK in cardiovascular health in relation to nitric oxide signaling. Further, we highlighted the biphasic effects of Y-27632, a ROCK inhibitor under shear stress, which acts as an agonist of nitric oxide production in endothelial cells. The biphasic effects of this inhibitor raised the question of safety of the drug usage in treating cardiovascular diseases.


Assuntos
Óxido Nítrico/metabolismo , Doenças Vasculares/enzimologia , Quinases Associadas a rho/metabolismo , Amidas/farmacologia , Amidas/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Doenças Vasculares/tratamento farmacológico , Quinases Associadas a rho/antagonistas & inibidores
15.
Nitric Oxide ; 36: 76-86, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24333563

RESUMO

Nitric oxide (NO) is a known modulator of angiogenesis. The NONOate subfamily of NO donors has long been used in experimental and clinical studies to promote angiogenesis. However, no studies have been conducted yet to compare the angiogenesis potential of these NO donors in respect to their pattern of NO release. We hypothesize that having different pattern of NO release, each of the NO donors in NONOate subfamily can promote key stages of angiogenesis in differential manner. To verify our hypothesis, NO donors with half life ranging from seconds to several hours and having very different pattern of NO release were selected to evaluate their efficacy in modulating angiogenesis. Endothelial tube formation using EAhy926 cells was maximally increased by Spermine NONOate (SP) treatment. SP treatment maximally induced both ex vivo and in vivo angiogenesis using egg yolk and cotton plug angiogenesis models respectively. Experiment using chick embryo partial ischemia model revealed SP as the best suited NO donor to recover ischemia driven hampered angiogenesis. The present study elaborated that differential release pattern of NO by different NO donors can modulate angiogenesis differentially and also suggested that SP have a unique pattern of NO release that best fits for angiogenesis.


Assuntos
Indutores da Angiogênese/química , Neovascularização Fisiológica , Doadores de Óxido Nítrico/química , Espermina/análogos & derivados , Animais , Aorta/metabolismo , Bovinos , Células Cultivadas , Embrião de Galinha , Gema de Ovo , Endotélio Vascular/metabolismo , Perfilação da Expressão Gênica , Isquemia/metabolismo , Masculino , Óxido Nítrico/química , Ratos , Ratos Wistar , Transdução de Sinais , Espermina/química , Cicatrização
16.
Arterioscler Thromb Vasc Biol ; 33(5): 999-1005, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23430614

RESUMO

OBJECTIVE: The G-protein-coupled receptor kinase interacting protein-1 (GIT1) is a scaffold protein that is important for phospholipase Cγ and extracellular signal-regulated kinase 1/2 signaling induced by angiotensin II and epidermal growth factor. Because GIT1 regulates signaling by several vascular smooth muscle cell (VSMC) growth factors, we hypothesized that intima formation would be inhibited by GIT1 depletion. APPROACH AND RESULTS: Complete carotid ligation was performed on GIT1 wild-type and knockout (KO) mice. We compared changes between GIT1 wild-type and KO mice in carotid vascular remodeling, VSMC proliferation, and apoptosis in vivo and in vitro. Our data demonstrated that GIT1 deficiency significantly decreased intima formation after carotid ligation as a result of both reduced VSMC proliferation and enhanced apoptosis. To confirm the effects of GIT1 in vitro, we performed proliferation and apoptosis assays in VSMC. In mouse aortic smooth muscle cells (MASM), we found that the growth rate and [3H]-thymidine incorporation of the GIT1 KO MASM were significantly decreased compared with the wild-type MASM. Cyclin D1, which is a key cell cycle regulator, was significantly decreased in GIT1 KO cells. Serum deprivation of GIT1 KO MASM increased apoptosis 3-fold compared with wild-type MASM. Treatment of rat aortic smooth muscle cells with GIT1 small interfering RNA impaired cell migration. Both phospholipase Cγ and extracellular signal-regulated kinase 1/2 signaling were required for GIT1-dependent VSMC proliferation and migration, whereas only phospholipase Cγ was involved in GIT1-mediated VSMC apoptosis. CONCLUSIONS: GIT1 is a novel mediator of vascular remodeling by regulating VSMC proliferation, migration, and apoptosis through phospholipase Cγ and extracellular signal-regulated kinase 1/2 signaling pathways.


Assuntos
Apoptose , Proteínas de Ciclo Celular/fisiologia , Proteínas Ativadoras de GTPase/fisiologia , Músculo Liso Vascular/citologia , Túnica Íntima/patologia , Animais , Ciclo Celular , Movimento Celular , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/fisiologia
17.
Life Sci ; 342: 122509, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387702

RESUMO

Acute kidney injury to chronic kidney disease (AKI-to-CKD) transition is a complex intermingling of characteristics of both AKI and CKD. Pathophysiologically, the transition lasts seven days after the AKI episode and thereafter silently progresses towards CKD. Growing reports confirm that the AKI-to-CKD transition is heavily regulated by epigenetic modifiers. Long non-coding RNAs (lncRNAs) share a diverse role in gene regulation at transcriptional and translational levels and have been reported to be involved in the regulation and progression of AKI-to-CKD transition. Several lncRNAs have been considered potential biomarkers for diagnosing kidney disease, including AKI and CKD. Targeting lncRNAs gives a promising therapeutic strategy against kidney diseases. The primitive role of lncRNA in the progression of the AKI-to-CKD transition is yet to be fully understood. As known, the lncRNAs could be used as a biomarker and a therapeutic target to halt the CKD development and progression after AKI. This review aims to deepen our understanding of the current knowledge regarding the involvement of lncRNAs in the AKI-to-CKD transition. This review primarily discusses the role of lncRNAs and the change in their mechanisms during different stages of kidney disease, such as in AKI, AKI-to-CKD transition, and CKD. Further, we have discussed the potential diagnostic and pharmacological outcomes of targeting lncRNAs to prevent or slow the progression of AKI-to-CKD transition.


Assuntos
Injúria Renal Aguda , RNA Longo não Codificante , Insuficiência Renal Crônica , Humanos , RNA Longo não Codificante/genética , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/genética , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/genética , Injúria Renal Aguda/terapia , Regulação da Expressão Gênica , Biomarcadores , Progressão da Doença , Rim
18.
Bioorg Med Chem Lett ; 23(1): 287-90, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23182087

RESUMO

Benzothiazole and benzimidazole containing phthalimide derivatives (NK037, NK041, NK042, NK0139A and NK0148) have been synthesized and their anti-angiogenic activity was evaluated using ex vivo egg yolk angiogenesis model. A comparative study with pure thalidomide (NKTA) has also been performed to describe the efficacy of these derivatives in blocking angiogenesis. NK037, NK041 and NK042 were equally potent in blocking egg yolk angiogenesis and the anti-angiogenesis effect was higher than NKTA suggesting the efficacy of these three derivatives in blocking angiogenesis when compare to control. Other two derivatives NK0139A and NK0148 showed effect less than NKTA and stronger than control in ex vivo angiogenesis.


Assuntos
Inibidores da Angiogênese/síntese química , Benzimidazóis/química , Benzotiazóis/química , Ftalimidas/química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Embrião de Galinha , Gema de Ovo/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Ftalimidas/síntese química , Ftalimidas/farmacologia
19.
Life Sci ; 321: 121643, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997061

RESUMO

Diabetic kidney disease (DKD) is a major diabetic complication and global health concern, occurring in nearly 30 % to 40 % of people with diabetes. Importantly, several therapeutic strategies are being used against DKD; however, available treatments are not uniformly effective and the continuous rise in the prevalence of DKD demands more potential therapeutic approaches or targets. Epigenetic modifiers are regarded for their potential therapeutic effects against DKD. E3 ligases are such epigenetic modifier that regulates the target gene expression by attaching ubiquitin to the histone protein. In recent years, the E3 ligases came up as a potential therapeutic target as it selectively attaches ubiquitin to the substrate proteins in the ubiquitination cascade and modulates cellular homeostasis. The E3 ligases are also actively involved in DKD by regulating the expression of several proteins involved in the proinflammatory and profibrotic pathways. Burgeoning reports suggest that several E3 ligases such as TRIM18 (tripartite motif 18), Smurf1 (Smad ubiquitination regulatory factor 1), and NEDD4-2 (neural precursor cell-expressed developmentally downregulated gene 4-2) are involved in kidney epithelial-mesenchymal transition, inflammation, and fibrosis by regulating respective signaling pathways. However, the various signaling pathways that are regulated by different E3 ligases in the progression of DKD are poorly understood. In this review, we have discussed E3 ligases as potential therapeutic target for DKD. Moreover, different signaling pathways regulated by E3 ligases in the progression of DKD have also been discussed.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Ubiquitinação , Ubiquitina/metabolismo , Transdução de Sinais/genética
20.
Life Sci ; 335: 122256, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949210

RESUMO

Diabetic kidney disease (DKD) is a leading diabetic complication causing significant mortality among people around the globe. People with poor glycemic control accompanied by hyperinsulinemia, dyslipidemia, hypertension, and obesity develop diabetic complications. These diabetic patients develop epigenetic changes and suffer from diabetic kidney complications even after subsequent glucose control, the phenomenon that is recognized as metabolic memory. DNA methylation is an essential epigenetic modification that contributes to the development and progression of several diabetic complications, including DKD. The aberrant DNA methylation pattern at CpGs sites within several genes, such as mTOR, RPTOR, IRS2, GRK5, SLC27A3, LCAT, and SLC1A5, associated with the accompanying risk factors exacerbate the DKD progression. Although drugs such as azacytidine and decitabine have been approved to target DNA methylation for diseases such as hematological malignancies, none have been approved for the treatment of DKD. More importantly, no DNA hypomethylation-targeting drugs have been approved for any disease conditions. Understanding the alteration in DNA methylation and its association with the disease risk factors is essential to target DKD effectively. This review has discussed the abnormal DNA methylation pattern and the kidney tissue-specific expression of critical genes involved in DKD onset and progression. Moreover, we also discuss the new possible therapeutic approach that can be exploited for treating DNA methylation aberrancy in a site-specific manner against DKD.


Assuntos
Complicações do Diabetes , Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Metilação de DNA , Rim/metabolismo , Complicações do Diabetes/metabolismo , Epigênese Genética , Diabetes Mellitus/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Sistema ASC de Transporte de Aminoácidos/metabolismo
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