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1.
Molecules ; 28(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570701

RESUMO

B-site cobalt (Co)-doped rare-earth orthoferrites ReFeO3 have shown considerable enhancement in physical properties compared to their parent counterparts, and Co-doped LuFeO3 has rarely been reported. In this work, LuFe1-xCoxO3 (x = 0, 0.05, 0.1, 0.15) powders have been successfully prepared by a mechanochemical activation-assisted solid-state reaction (MAS) method at 1100 °C for 2 h. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy studies demonstrated that a shrinkage in lattice parameters emerges when B-site Fe ions are substituted by Co ions. The morphology and elemental distribution were investigated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The UV-visible absorbance spectra show that LuFe0.85Co0.15O3 powders have a narrower bandgap (1.75 eV) and higher absorbance than those of LuFeO3 (2.06 eV), obviously improving the light utilization efficiency. Additionally, LuFe0.85Co0.15O3 powders represent a higher photocatalytic capacity than LuFeO3 powders and can almost completely degrade MO in 5.5 h with the assistance of oxalic acid under visible irradiation. We believe that the present study will promote the application of orthorhombic LuFeO3 in photocatalysis.

2.
Kidney Int ; 103(3): 529-543, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36565808

RESUMO

Chronic kidney disease (CKD) is a common cause of morbidity in human immunodeficiency virus (HIV)-positive individuals. HIV infection leads to a wide spectrum of kidney cell damage, including tubular epithelial cell (TEC) injury. Among the HIV-1 proteins, the pathologic effects of viral protein R (Vpr) are well established and include DNA damage response, cell cycle arrest, and cell death. Several in vitro studies have unraveled the molecular pathways driving the cytopathic effects of Vpr in tubular epithelial cells. However, the in vivo effects of Vpr on tubular injury and CKD pathogenesis have not been thoroughly investigated. Here, we use a novel inducible tubular epithelial cell-specific Vpr transgenic mouse model to show that Vpr expression leads to progressive tubulointerstitial damage, interstitial inflammation and fibrosis, and tubular cyst development. Importantly, Vpr-expressing tubular epithelial cells displayed significant hypertrophy, aberrant cell division, and atrophy; all reminiscent of tubular injuries observed in human HIV-associated nephropathy (HIVAN). Single-cell RNA sequencing analysis revealed the Vpr-mediated transcriptomic responses in specific tubular subsets and highlighted the potential multifaceted role of p53 in the regulation of cell metabolism, proliferation, and death pathways in Vpr-expressing tubular epithelial cells. Thus, our study demonstrates that HIV Vpr expression in tubular cells is sufficient to induce HIVAN-like tubulointerstitial damage and fibrosis, independent of glomerulosclerosis and proteinuria. Additionally, as this new mouse model develops progressive CKD with diffuse fibrosis and kidney failure, it can serve as a useful tool to examine the mechanisms of kidney disease progression and fibrosis in vivo.


Assuntos
Nefropatia Associada a AIDS , Produtos do Gene vpr , Infecções por HIV , HIV-1 , Insuficiência Renal Crônica , Animais , Humanos , Camundongos , Nefropatia Associada a AIDS/genética , Modelos Animais de Doenças , Produtos do Gene vpr/genética , Produtos do Gene vpr/metabolismo , Produtos do Gene vpr/farmacologia , Infecções por HIV/complicações , HIV-1/genética , HIV-1/metabolismo , Proteínas do Vírus da Imunodeficiência Humana , Camundongos Transgênicos , Insuficiência Renal Crônica/complicações
3.
Kidney Int ; 102(2): 293-306, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35469894

RESUMO

Recent epidemiological studies suggest that some patients with diabetes progress to kidney failure without significant albuminuria and glomerular injury, suggesting a critical role of kidney tubular epithelial cell (TEC) injury in diabetic kidney disease (DKD) progression. However, the major risk factors contributing to TEC injury and progression in DKD remain unclear. We previously showed that expression of endoplasmic reticulum-resident protein Reticulon-1A (RTN1A) increased in human DKD, and the increased RTN1A expression promoted TEC injury through endoplasmic reticulum (ER) stress response. Here, we show that TEC-specific RTN1A overexpression worsened DKD in mice, evidenced by enhanced tubular injury, tubulointerstitial fibrosis, and kidney function decline. But RTN1A overexpression did not exacerbate diabetes-induced glomerular injury or albuminuria. Notably, RTN1A overexpression worsened both ER stress and mitochondrial dysfunction in TECs under diabetic conditions by regulation of ER-mitochondria contacts. Mechanistically, ER-bound RTN1A interacted with mitochondrial hexokinase-1 and the voltage-dependent anion channel-1 (VDAC1), interfering with their association. This disengagement of VDAC1 from hexokinase-1 resulted in activation of apoptotic and inflammasome pathways, leading to TEC injury and loss. Thus, our observations highlight the importance of ER-mitochondrial crosstalk in TEC injury and the salient role of RTN1A-mediated ER-mitochondrial contact regulation in DKD progression.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Retículo Endoplasmático , Mitocôndrias , Proteínas do Tecido Nervoso , Albuminúria/metabolismo , Animais , Apoptose , Diabetes Mellitus/metabolismo , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Células Epiteliais/metabolismo , Hexoquinase/metabolismo , Humanos , Camundongos , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/genética
4.
Arterioscler Thromb Vasc Biol ; 41(9): 2483-2493, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34320838

RESUMO

Objective: Despite considerable research, the goal of finding nonsurgical remedies against thoracic aortic aneurysm and acute aortic dissection remains elusive. We sought to identify a novel aortic PK (protein kinase) that can be pharmacologically targeted to mitigate aneurysmal disease in a well-established mouse model of early-onset progressively severe Marfan syndrome (MFS). Approach and Results: Computational analyses of transcriptomic data derived from the ascending aorta of MFS mice predicted a probable association between thoracic aortic aneurysm and acute aortic dissection development and the multifunctional, stress-activated HIPK2 (homeodomain-interacting protein kinase 2). Consistent with this prediction, Hipk2 gene inactivation significantly extended the survival of MFS mice by slowing aneurysm growth and delaying transmural rupture. HIPK2 also ranked among the top predicted PKs in computational analyses of DEGs (differentially expressed genes) in the dilated aorta of 3 MFS patients, which strengthened the clinical relevance of the experimental finding. Additional in silico analyses of the human and mouse data sets identified the TGF (transforming growth factor)-ß/Smad3 signaling pathway as a potential target of HIPK2 in the MFS aorta. Chronic treatment of MFS mice with an allosteric inhibitor of HIPK2-mediated stimulation of Smad3 signaling validated this prediction by mitigating thoracic aortic aneurysm and acute aortic dissection pathology and partially improving aortic material stiffness. Conclusions: HIPK2 is a previously unrecognized determinant of aneurysmal disease and an attractive new target for antithoracic aortic aneurysm and acute aortic dissection multidrug therapy.


Assuntos
Aorta Torácica/efeitos dos fármacos , Aneurisma da Aorta Torácica/prevenção & controle , Dissecção Aórtica/prevenção & controle , Fibrilina-1/genética , Síndrome de Marfan/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Remodelação Vascular/efeitos dos fármacos , Adulto , Dissecção Aórtica/enzimologia , Dissecção Aórtica/genética , Dissecção Aórtica/patologia , Animais , Aorta Torácica/enzimologia , Aorta Torácica/patologia , Aneurisma da Aorta Torácica/enzimologia , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/patologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Dilatação Patológica , Modelos Animais de Doenças , Progressão da Doença , Humanos , Masculino , Síndrome de Marfan/complicações , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Proteína Smad3/metabolismo
5.
Kidney Int ; 99(4): 914-925, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33359498

RESUMO

With the widespread use combination antiretroviral therapy, there has been a dramatic decrease in HIV-associated nephropathy. However, although the patients living with HIV have low or undetectable viral load, the prevalence of chronic kidney disease (CKD) in this population remains high. Additionally, improved survival is associated with aging-related comorbidities such as diabetes and cardiovascular disease. A faster progression of CKD is associated with concurrent HIV infection and diabetes than with HIV infection or diabetes alone. To explore the potential pathogenic mechanisms that synergistically drive CKD progression by diabetes and HIV infection, we generated a new mouse model with a relatively low expression of HIV-1 proviral genes specifically in podocytes (pod-HIV mice) to better mimic the setting of kidney injury in patients living with HIV. While no apparent kidney phenotypes were observed at baseline in pod-HIV mice, the induction of mild diabetic kidney disease with streptozotocin led to significant worsening of albuminuria, glomerular injury, podocyte loss, and kidney dysfunction as compared to the mice with diabetes alone. Mechanistically, diabetes and HIV-1 synergistically increased the glomerular expression of microRNA-34a (miR-34a), thereby reducing the expression of Sirtuin-1 (SIRT1) deacetylase. These changes were also associated with increased acetylation and activation of p53 and p65 NF-κB and with enhanced expression of senescence and inflammatory markers. The treatment of diabetic pod-HIV mice with the specific Sirtuin-1 agonist BF175 significantly attenuated albuminuria and glomerulopathy. Thus, our study highlights the reduction in Sirtuin-1 as a major basis of CKD progression in diabetic patients living with HIV and suggests Sirtuin-1 agonists as a potential therapy.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Infecções por HIV , Podócitos , Albuminúria/genética , Animais , Nefropatias Diabéticas/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Glomérulos Renais , Camundongos
6.
Nanomaterials (Basel) ; 10(8)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796739

RESUMO

To explore the origin of magnetism, the effect of light Cu-doping on ferromagnetic and photoluminescence properties of ZnO nanocrystals was investigated. These Cu-doped ZnO nanocrystals were prepared using a facile solution method. The Cu2+ and Cu+ ions were incorporated into Zn sites, as revealed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). At the Cu concentration of 0.25 at.%, the saturated magnetization reached the maximum and then decreased with increasing Cu concentration. With increasing Cu concentration, the photoluminescence (PL) spectroscopy indicated the distribution of VO+ and VO++ vacancies nearly unchanged. These results indicate that Cu ions can enhance the long-range ferromagnetic ordering at an ultralow concentration, but antiferromagnetic "Cu+-Vo-Cu2+" couples may also be generated, even at a very low Cu-doping concentration.

7.
J Exp Med ; 217(9)2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32717081

RESUMO

Kidney glomerulosclerosis commonly progresses to end-stage kidney failure, but pathogenic mechanisms are still poorly understood. Here, we show that podocyte expression of decay-accelerating factor (DAF/CD55), a complement C3 convertase regulator, crucially controls disease in murine models of adriamycin (ADR)-induced focal and segmental glomerulosclerosis (FSGS) and streptozotocin (STZ)-induced diabetic glomerulosclerosis. ADR induces enzymatic cleavage of DAF from podocyte surfaces, leading to complement activation. C3 deficiency or prevention of C3a receptor (C3aR) signaling abrogates disease despite DAF deficiency, confirming complement dependence. Mechanistic studies show that C3a/C3aR ligations on podocytes initiate an autocrine IL-1ß/IL-1R1 signaling loop that reduces nephrin expression, causing actin cytoskeleton rearrangement. Uncoupling IL-1ß/IL-1R1 signaling prevents disease, providing a causal link. Glomeruli of patients with FSGS lack DAF and stain positive for C3d, and urinary C3a positively correlates with the degree of proteinuria. Together, our data indicate that the development and progression of glomerulosclerosis involve loss of podocyte DAF, triggering local, complement-dependent, IL-1ß-induced podocyte injury, potentially identifying new therapeutic targets.


Assuntos
Antígenos CD55/metabolismo , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Podócitos/metabolismo , Podócitos/patologia , Citoesqueleto de Actina/metabolismo , Idoso , Animais , Antígenos CD55/deficiência , Linhagem Celular Transformada , Ativação do Complemento/imunologia , Complemento C3b/metabolismo , Diabetes Mellitus Experimental/patologia , Suscetibilidade a Doenças , Regulação para Baixo , Doxorrubicina/efeitos adversos , Feminino , Glomerulosclerose Segmentar e Focal/induzido quimicamente , Glomerulosclerose Segmentar e Focal/imunologia , Humanos , Interleucina-1beta/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Especificidade de Órgãos , Fosfolipase D/metabolismo , Podócitos/ultraestrutura , Receptores de Complemento/metabolismo , Transdução de Sinais
8.
JCI Insight ; 5(17)2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32701510

RESUMO

We previously used global Hipk2-null mice in various models of kidney disease to demonstrate the central role of homeodomain-interacting protein kinase 2 (HIPK2) in renal fibrosis development. However, renal tubular epithelial cell-specific (RTEC-specific) HIPK2 function in renal fibrogenesis has yet to be determined. Here, we show that modulation of tubular HIPK2 expression and activity affects renal fibrosis development in vivo. The loss of HIPK2 expression in RTECs resulted in a marked diminution of renal fibrosis in unilateral ureteral obstruction (UUO) mouse models and HIV-associated nephropathy (HIVAN) mouse models, which was associated with the reduction of Smad3 activation and downstream expression of profibrotic markers. Conversely, WT HIPK2 overexpression in RTECs accentuated the extent of renal fibrosis in the setting of UUO, HIVAN, and folic acid-induced nephropathy in mice. Notably, kinase-dead HIPK2 mutant overexpression or administration of BT173, an allosteric inhibitor of HIPK2-Smad3 interaction, markedly attenuated the renal fibrosis in these mouse models of kidney disease, indicating that HIPK2 requires both the kinase activity and its interaction with Smad3 to promote TGF-ß-mediated renal fibrosis. Together, these results establish an important RTEC-specific role of HIPK2 in kidney fibrosis and further substantiate the inhibition of HIPK2 as a therapeutic approach against renal fibrosis.


Assuntos
Nefropatia Associada a AIDS/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Insuficiência Renal Crônica/metabolismo , Nefropatia Associada a AIDS/patologia , Animais , Fibrose , Humanos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Mutação com Perda de Função , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/genética , Insuficiência Renal Crônica/patologia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo
9.
Cell Physiol Biochem ; 48(1): 63-74, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30001528

RESUMO

BACKGROUND/AIMS: Glomerular endothelial cell injury plays a crucial role in the development of diabetic nephropathy (DN). CD146, an endothelial marker, was shown to increase in chronic kidney disease (CKD), but its role in DN remains unknown. We aim to assess whether CD146 could be used to evaluate disease severity and predict renal outcomes in DN at early stages. METHODS: 159 non-dialysis type 2-DN patients from 2008 to 2015 were enrolled to measure the plasma concentration of soluble CD146 (sCD146). 94 type 2 diabetes mellitus patients without DN and 100 healthy subjects were used as controls. The patients with CKD stage 1-3 were referred as early stage patients. Another independent cohort of 48 patients with biopsy-proved DN was used for the immunohistochemistry study of CD146. Renal outcomes were defined as doubling of serum creatinine, initiation of renal replacement therapy or death. RESULTS: We found that plasma level of sCD146 was upregulated and associated with renal function in DN patients. sCD146 was proved to be a more optimal marker than urine albumin creatinine ratio to evaluate disease severity in these DN patients. The kidney expression of CD146 was co-localized with endothelial marker CD31 and increased in DN. CD146 staining in kidney was correlated with the severity of pathological changes in DN patients. Survival analysis suggested that both plasma and biopsy expression of CD146 were correlated with renal outcomes. CONCLUSIONS: CD146 is associated with kidney injury and could be a good marker to predict renal outcomes in patients with early stages of DN.


Assuntos
Biomarcadores/sangue , Antígeno CD146/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatias Diabéticas/patologia , Rim/patologia , Adulto , Idoso , Área Sob a Curva , Estudos de Casos e Controles , Creatinina/sangue , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/complicações , Feminino , Taxa de Filtração Glomerular , Humanos , Imuno-Histoquímica , Rim/metabolismo , Masculino , Pessoa de Meia-Idade , Curva ROC , Albumina Sérica/análise , Índice de Gravidade de Doença , Regulação para Cima
10.
Cell Death Dis ; 8(5): e2772, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28492542

RESUMO

Long non-coding RNA HOTAIR was regarded as an oncogene in multiple cancers. Previous studies have shown that HOTAIR is involved in the proliferation and tumorigenesis of renal carcinoma cells, while microRNA (miR)-217 functions as a tumor suppressor in renal cell carcinoma (Rcc). However, the underlying molecular mechanism of HOTAIR in Rcc, especially in association with miR-217, has not been studied. In this study, we first demonstrated that HOTAIR expression was upregulated, which was correlated with tumor progression, and miR-217 downregulated in Rcc tissues and cells. Importantly, HOTAIR expression was negatively correlated with miR-217 expression in Rcc tissues. Gain- and loss-of-function of HOTAIR revealed that HOTAIR functioned as a ceRNA for miR-217 to facilitate HIF-1α expression and then upregulated AXL level promoting Rcc proliferation, migration, and EMT process, and inhibiting apoptosis. Furthermore, HOTAIR knockdown suppressed tumor growth and reduced the expression of proliferation antigen ki-67, HIF-1α, and AXL, but upregulated the expression of miR-217 in vivo. Finally, with AXL inhibitor BGB324, we confirmed that HOTAIR promoted Rcc activity through AXL signaling both in vitro and in vivo. In conclusion, these results suggest that HOTAIR promotes Rcc tumorigenesis via miR-217/HIF-1α/AXL signaling, which may provide a new target for the diagnosis and therapy of Rcc disease.


Assuntos
Carcinoma de Células Renais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Renais/metabolismo , MicroRNAs/biossíntese , Proteínas Proto-Oncogênicas/metabolismo , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Benzocicloeptenos/farmacologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , MicroRNAs/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Triazóis/farmacologia , Receptor Tirosina Quinase Axl
11.
Sci Rep ; 7(1): 323, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28336924

RESUMO

We previously reported a critical role of reticulon (RTN) 1A in mediating endoplasmic reticulum (ER) stress in kidney tubular cells and the expression of RTN1A correlates with the renal function and the severity of kidney injury in patients with diabetic nephropathy (DN). Here, we determined the roles of RTN1A and ER stress in podocyte injury and DN. We used db/db mice with early unilateral nephrectomy (Unx) as a murine model of progressive DN and treated mice with tauroursodeoxycholic acid (TUDCA), a specific inhibitor of ER stress. We found increased expression of RTN1A and ER stress markers in the kidney of db/db-Unx mice. Treatment of TUDCA not only attenuated proteinuria and kidney histological changes, but also ameliorated podocyte and glomeruli injury in diabetic mice, which were associated with reduction of RTN1A and ER stress marker expression in the podocytes of TUDCA-treated mice. In vitro, we showed RTN1A mediates albumin-induced ER stress and apoptosis in human podocytes. A positive feedback loop between RTN1A and CHOP was found leading to an enhanced ER stress in podocytes. Our data suggest that ER stress plays a major role in podocyte injury in DN and RTN1A might be a key regulator of ER stress in podocytes.


Assuntos
Nefropatias Diabéticas/fisiopatologia , Estresse do Retículo Endoplasmático , Proteínas do Tecido Nervoso/metabolismo , Podócitos/patologia , Podócitos/fisiologia , Animais , Modelos Animais de Doenças , Camundongos
12.
J Am Soc Nephrol ; 28(7): 2133-2143, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28220029

RESUMO

Homeodomain interacting protein kinase 2 (HIPK2) is a critical regulator of multiple profibrotic pathways, including that of TGF-ß1/Smad3. Genetic ablation of HIPK2 was shown previously to significantly reduce renal fibrosis in the experimental unilateral ureteral obstruction model and Tg26 mice, a model of HIV-associated nephropathy. To develop specific pharmacologic inhibitors of HIPK2 for antifibrotic therapy, we designed and synthesized small molecule inhibitor compounds on the basis of the predicted structure of HIPK2. Among these compounds, we identified one, BT173, that strongly inhibited the ability of HIPK2 to potentiate the downstream transcriptional activity of Smad3 in kidney tubular cells. Notably, binding of BT173 to HIPK2 did not inhibit HIPK2 kinase activity but rather, interfered allosterically with the ability of HIPK2 to associate with Smad3. In vitro, treatment with BT173 inhibited TGF-ß1-induced Smad3 phosphorylation and Smad3 target gene expression in human renal tubular epithelial cells. In vivo, administration of BT173 decreased Smad3 phosphorylation and mitigated renal fibrosis and deposition of extracellular matrix in unilateral ureteral obstruction and Tg26 mouse models of renal fibrosis. Our data indicate that BT173 is a novel HIPK2 inhibitor that attenuates renal fibrosis through suppression of the TGF-ß1/Smad3 pathway and may be developed as an antifibrotic therapy in patients with kidney disease.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Rim/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/antagonistas & inibidores , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Animais , Fibrose/prevenção & controle , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxidiazóis/farmacologia , Oxidiazóis/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Fator de Crescimento Transformador beta1/fisiologia
13.
J Am Soc Nephrol ; 28(7): 2007-2021, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28137829

RESUMO

Several animal studies have shown an important role for endoplasmic reticulum (ER) stress in AKI, whereas human studies are lacking. We recently reported that Reticulon-1A (RTN1A) is a key mediator of ER stress and kidney cell injury. Here, we investigated whether modulation of RTN1A expression during AKI contributes to the progression to CKD. In a retrospective study of 51 patients with AKI, increased expression of RTN1A and other ER stress markers were associated with the severity of kidney injury and with progression to CKD. In an inducible tubular cell-specific RTN1A-knockdown mouse model subjected to folic acid nephropathy (FAN) or aristolochic acid nephropathy, reduction of RTN1A expression during the initial stage of AKI attenuated ER stress and kidney cell injury in early stages and renal fibrosis development in later stages. Treatment of wild-type mice with tauroursodeoxycholic acid, an inhibitor of ER stress, after the induction of kidney injury with FA facilitated renoprotection similar to that observed in RTN1A-knockdown mice. Conversely, in transgenic mice with inducible tubular cell-specific overexpression of RTN1A subjected to FAN, induction of RTN1A overexpression aggravated ER stress and renal injury at the early stage and renal fibrosis at the late stage of FAN. Together, our human and mouse data suggest that the RTN1A-mediated ER stress response may be an important determinant in the severity of AKI and maladaptive repair that may promote progression to CKD.


Assuntos
Injúria Renal Aguda/etiologia , Estresse do Retículo Endoplasmático , Rim/patologia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Animais , Progressão da Doença , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fibrose/prevenção & controle , Humanos , Masculino , Camundongos , Insuficiência Renal Crônica/etiologia , Estudos Retrospectivos , Índice de Gravidade de Doença
14.
Cell Commun Signal ; 15(1): 3, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-28057038

RESUMO

BACKGROUND: Uric acid (UA) is an antioxidant found in human serum. However, high UA levels may also have pro-oxidant functions. According to previous research, aldose reductase (AR) plays a vital role in the oxidative stress-related complications of diabetes. We sought to determine the mechanism by which UA becomes deleterious at high concentrations as well as the effect of AR in this process. METHOD: Endothelial cells were divided into three groups cultured without UA or with 300 µM or 600 µM UA. The levels of total reactive oxygen species (ROS), of four ROS components, and of NO and NOX4 expression were measured. Changes in the above molecules were detected upon inhibiting NOX4 or AR, and serum H2O2 and vWF levels were measured in vivo. RESULTS: Increased AR expression in high UA-treated endothelial cells enhanced ROS production by activating NADPH oxidase. These effects were blocked by the AR inhibitor epalrestat. 300 µM UA decreased the levels of the three major reactive oxygen species (ROS) components: O2•-, •OH, and 1O2. However, when the UA concentration was increased, both O2•- levels and downstream H2O2 production significantly increased. Finally, an AR inhibitor reduced H2O2 production in hyperuricemic mice and protected endothelial cell function. CONCLUSIONS: Our findings indicate that inhibiting AR or degrading H2O2 could protect endothelial function and maintain the antioxidant activities of UA. These findings provide new insight into the role of UA in chronic kidney disease.


Assuntos
Aldeído Redutase/metabolismo , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/patologia , Ácido Úrico/farmacologia , Aldeído Redutase/antagonistas & inibidores , Animais , Catalase/farmacologia , Citoproteção/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Hiperuricemia/metabolismo , Camundongos , Modelos Biológicos , NADPH Oxidases/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Rodanina/análogos & derivados , Rodanina/farmacologia , Tiazolidinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
J Am Soc Nephrol ; 28(5): 1385-1393, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27927780

RESUMO

Renal fibrosis is the common pathway of progression for patients with CKD and chronic renal allograft injury (CAI), but the underlying mechanisms remain obscure. We performed a meta-analysis in human kidney biopsy specimens with CAI, incorporating data available publicly and from our Genomics of Chronic Renal Allograft Rejection study. We identified an Src family tyrosine kinase, hematopoietic cell kinase (Hck), as upregulated in allografts in CAI. Querying the Kinase Inhibitor Resource database revealed that dasatinib, a Food and Drug Administration-approved drug, potently binds Hck with high selectivity. In vitro, Hck overexpression activated the TGF-ß/Smad3 pathway, whereas HCK knockdown inhibited it. Treatment of tubular cells with dasatinib reduced the expression of Col1a1 Dasatinib also reduced proliferation and α-SMA expression in fibroblasts. In a murine model with unilateral ureteric obstruction, pretreatment with dasatinib significantly reduced the upregulation of profibrotic markers, phosphorylation of Smad3, and renal fibrosis observed in kidneys pretreated with vehicle alone. Dasatinib treatment also improved renal function, reduced albuminuria, and inhibited expression of profibrotic markers in animal models with lupus nephritis and folic acid nephropathy. These data suggest that Hck is a key mediator of renal fibrosis and dasatinib could be developed as an antifibrotic drug.


Assuntos
Nefropatias/genética , Transplante de Rim , Rim/patologia , Complicações Pós-Operatórias/genética , Proteínas Proto-Oncogênicas c-hck/genética , Proteínas Proto-Oncogênicas c-hck/fisiologia , Animais , Feminino , Fibrose/genética , Genômica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Oncotarget ; 8(67): 111295-111308, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29340054

RESUMO

Hyperuricemia contributes to kidney tubular injury and kidney fibrosis. However, the underlying mechanism remains unclear. Here we examined the role of RTN1A, a novel endoplasmic reticulum (ER)-associated protein and ER stress in hyperuricemic nephropathy. We first found the expression of RTN1A and ER stress markers was significantly increased in kidney biopsies of hyperuricemia patients with kidney injury. In a rat model of hyperuricemic nephropathy (HN) established by oral administration of a mixture of adenine and potassium oxonate, increased expression of RTN1A and ER stress was shown in tubular and interstitial compartment of rat kidneys. Treatment of Febuxostat, a new selective inhibitor of xanthine oxidase (XO), not only attenuated renal tubular injury and tubulointerstitial fibrosis, but also reduced uric acid crystals deposition in HN rat kidneys. In vitro, Febuxostat also reduced ER stress and apoptosis in uric acid treated tubular epithelial cells. Our data suggest that RTN1A and ER stress mediate tubular cell injury and kidney fibrosis in HN. Urate-lowering therapy (ULT) with Febuxostat attenuates uric-acid induced ER stress in renal tubular cells and the progression of HN.

17.
Am J Physiol Renal Physiol ; 310(5): F409-15, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26739891

RESUMO

Our previous studies have suggested a critical role of reticulon (RTN)1A in mediating endoplasmic reticulum (ER) stress in kidney cells of animal models and humans with kidney diseases. A large body of evidence suggests that proteinuria itself can cause tubular cell injury leading to the progression of kidney disease. In the present study, we determined whether RTN1A mediates proteinuria-induced tubular cell injury through increased ER stress. We found that incubation of HK2 cells with human serum albumin induced the expression of RTN1A and ER stress markers, whereas knockdown of RTN1A expression attenuated human serum albumin-induced ER stress and tubular cell apoptosis in vitro. In vivo, we found that tubular cell-specific RTN1 knockdown resulted in a significant attenuation of tubular cell ER stress, apoptosis, and renal fibrosis in a model of albumin overload nephropathy. Based on these findings, we conclude that RTN1A is a key mediator for proteinuria-induced tubular cell toxicity and renal fibrosis.


Assuntos
Albuminúria/metabolismo , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Túbulos Renais/efeitos dos fármacos , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/metabolismo , Insuficiência Renal Crônica/prevenção & controle , Soroalbumina Bovina , Albumina Sérica/toxicidade , Albuminúria/induzido quimicamente , Albuminúria/genética , Albuminúria/patologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Fibrose , Genótipo , Células HEK293 , Humanos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Fenótipo , Interferência de RNA , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Albumina Sérica Humana , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
18.
Eur Spine J ; 25(5): 1587-1594, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26649555

RESUMO

OBJECTIVE: We prospectively compared posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) used in adult isthmic spondylolisthesis (IS) after surgical reduction with pedicle screws. METHODS: Between January 2009 and December 2010, 66 adult patients with single-level IS were randomly assigned to two groups treated using the PLIF technique (PLIF group, n = 34) and the TLIF technique (TLIF group, n = 32). Both groups were followed up for an average of 30.5 months (range 24-48 months). Clinical outcomes were assessed using the visual analog scale (VAS), Oswestry disability index (ODI) and Japanese orthopedic association (JOA) scores. Radiographic outcomes included percentage of vertebral slippage, focal lordosis and disk height. Clinical and radiographic outcomes were compared between the two groups. RESULTS: The average operative time and blood loss during surgery were significantly more in PLIF group than in TLIF group. Spondylolisthesis, disk height and focal lordosis were significantly improved postoperatively in both groups. There was no obvious difference in clinical outcomes, as assessed using the VAS, ODI and JOA scores, and radiographic outcomes. In PLIF group, there were two cases of neuropathic pain after surgery. CONCLUSIONS: After instrumented reduction of adult IS, either PLIF or TLIF can provide good clinical and radiological outcomes. With a single cage, TLIF was superior to PLIF in terms of surgical time and blood loss, but these differences may not be clinically relevant.


Assuntos
Vértebras Lombares/cirurgia , Parafusos Pediculares , Fusão Vertebral/métodos , Espondilolistese/cirurgia , Adulto , Perda Sanguínea Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Adulto Jovem
19.
Spine (Phila Pa 1976) ; 41(8): 653-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26630417

RESUMO

STUDY DESIGN: A prospective randomized clinical trial. OBJECTIVE: In this study, we determine whether percutaneous vertebroplasty (PVP) offers extra benefits to aged patients with acute osteoporotic vertebral compression fractures (OVCFs) over conservative therapy (CV). SUMMARY OF BACKGROUND DATA: OVCFs are common in the aged population with osteoporosis. While the optimal treatment of aged patients with acute OVCFs remains controversial, PVP, a minimally invasive procedure, is a treatment option to be considered. METHODS: Patients aged at 70 years or above with acute OVCF and severe pain from minor or mild trauma were assigned randomly to PVP and CV groups. The primary outcome was pain relief as measured by VAS score in 1-year follow-up period. The second outcome was quality of life assessed with ODI and Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO). Patient satisfaction surveys were also recorded. RESULTS: A total of 135 patients were enrolled, and 107 (56 in PVP group; 51 in CV group) completed 1-year follow-up. In PVP group, the vertebroplasty procedure was performed at a mean of 8.4 ±â€Š4.6 days (range, 2-21 days) after onset. Vertebroplasty resulted in much greater pain relief than did conservative treatment at postoperative day 1 (P < 0.0001). At every time point of follow-up, pain relief and quality of life were significantly improved in PVP group than in CV group at 1 week, 1 month, 3 months, 6 months, and 1 year (all P < 0.0001). The final follow-up surveys indicated that patients in PVP group were significantly more satisfied with given treatment (P < 0.0001). In addition, lower rate of complications was observed in PVP group (P < 0.0001). CONCLUSION: In aged patients with acute OVCF and severe pain, early vertebroplasty yielded faster, better pain relief and improved functional outcomes, which were maintained for 1 year. Furthermore, it showed fewer complications than conservative treatment. LEVEL OF EVIDENCE: 2.


Assuntos
Fraturas por Compressão/terapia , Procedimentos Cirúrgicos Minimamente Invasivos/estatística & dados numéricos , Fraturas por Osteoporose/terapia , Fraturas da Coluna Vertebral/terapia , Vertebroplastia/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Dor nas Costas , Repouso em Cama , Conservadores da Densidade Óssea/uso terapêutico , Feminino , Fraturas por Compressão/epidemiologia , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fraturas por Osteoporose/epidemiologia , Satisfação do Paciente , Fraturas da Coluna Vertebral/epidemiologia , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos
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