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1.
Int J Mol Sci ; 22(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34360633

RESUMO

Hyperglycemic conditions (HG), at early stages of diabetic nephropathy (DN), cause a decrease in podocyte numbers and an aberration of their function as key cells for glomerular plasma filtration. Klotho protein was shown to overcome some negative effects of hyperglycemia. Klotho is also a coreceptor for fibroblast growth factor receptors (FGFRs), the signaling of which, together with a proper rate of glycolysis in podocytes, is needed for a proper function of the glomerular filtration barrier. Therefore, we measured levels of Klotho in renal tissue, serum, and urine shortly after DN induction. We investigated whether it influences levels of FGFRs, rates of glycolysis in podocytes, and albumin permeability. During hyperglycemia, the level of membrane-bound Klotho in renal tissue decreased, with an increase in the shedding of soluble Klotho, its higher presence in serum, and lower urinary excretion. The addition of Klotho increased FGFR levels, especially FGFR1/FGFR2, after their HG-induced decrease. Klotho also increased levels of glycolytic parameters of podocytes, and decreased podocytic and glomerular albumin permeability in HG. Thus, we found that the decrease in the urinary excretion of Klotho might be an early biomarker of DN and that Klotho administration may have several beneficial effects on renal function in DN.


Assuntos
Glucuronidase/metabolismo , Hiperglicemia/metabolismo , Podócitos/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Animais , Glicólise , Masculino , Permeabilidade , Ratos Wistar
2.
Am J Physiol Lung Cell Mol Physiol ; 321(4): L736-L749, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34346778

RESUMO

Normal lungs do not express α-Klotho (Klotho) protein but derive cytoprotection from circulating soluble Klotho. It is unclear whether chronic supranormal Klotho levels confer additional benefit. To address this, we tested the age-related effects of modest Klotho overexpression on acute lung injury (ALI) and recovery. Transgenic Klotho-overexpressing (Tg-Kl) and wild-type (WT) mice (2 and 6 mo old) were exposed to hyperoxia (95% O2; 72 h; injury; Hx) then returned to normoxia (21% O2; 24 h; recovery; Hx-R). Control mice were kept in normoxia. Renal and serum Klotho, lung histology, and bronchoalveolar lavage fluid oxidative damage markers were assessed. Effects of hyperoxia on Klotho release were tested in human embryonic kidney cells stably expressing Klotho. A549 lung epithelial cells transfected with Klotho cDNA or vector were exposed to cigarette smoke; lactate dehydrogenase and double-strand DNA breaks were measured. Serum Klotho decreased with age. Hyperoxia suppressed renal Klotho at both ages and serum Klotho at 2 mo of age. Tg-Kl mice at both ages and 2-mo-old WT mice survived Hx-R; 6-mo-old Tg-Kl mice showed lower lung damage than age-matched WT mice. Hyperoxia directly inhibited Klotho expression and release in vitro; Klotho transfection attenuated cigarette smoke-induced cytotoxicity and DNA double-strand breaks in lung epithelial cells. Young animals with chronic high baseline Klotho expression were more resistant to ALI. Chronic constitutive Klotho overexpression in older Tg-Kl animals attenuated hyperoxia-induced lung damage and improves survival and short-term recovery despite an acute reduction in serum Klotho during injury. We conclude that chronic enhancement of Klotho expression increases resilience to ALI.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Glucuronidase/sangue , Glucuronidase/metabolismo , Fumaça/efeitos adversos , Lesão Pulmonar Aguda/patologia , Animais , Linhagem Celular , Citoproteção/genética , Citoproteção/fisiologia , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Feminino , Glucuronidase/genética , Células HEK293 , Humanos , Hiperóxia , L-Lactato Desidrogenase/análise , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Transgênicos
3.
Sci Rep ; 11(1): 15877, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354161

RESUMO

Chronic kidney disease (CKD) has been associated with a higher risk of cardiovascular disease (CVD). CKD patients present a decrease in the levels of the protein Klotho that accompanies the decrease in kidney function. This protein has been related to protective effects against CVD. However, it is unclear whether circulating Klotho, and its expression in peripheral blood cells (PBCs) are also associated with subclinical atherosclerosis in CKD. The present study aimed to study the relationship between Klotho and subclinical atherosclerosis in a population of patients with moderate to severe CKD. We determined the serum levels and gene expression in PBCs levels of Klotho and three inflammatory cytokines in 103 patients with CKD and investigated their relationship with two surrogate markers of subclinical atherosclerotis: ankle-brachial index (ABI) and carotid intima-media thickness (CIMT). Patients with subclinical atherosclerosis presented lower serum and PBCs expression levels of Klotho. Both variables were associated with the presence of subclinical atherosclerosis, being directly related with ABI and inversely with CIMT (P < 0.0001 for both). Multiple regression analysis demonstrated that both variables were significant determinants for ABI (adjusted R2 = 0.511, P < 0.0001) and CIMT (adjusted R2 = 0.445, P < 0.0001), independently of traditional and emergent cardiovascular risk factors. Moreover, both constituted protective factors against subclinical atherosclerosis [OR: 0.993 (P = 0.002) and 0.231 (P = 0.025), respectively]. Receiver operating characteristic analysis pointed to the utility of serum Klotho (area under the curve [AUC]: 0.817, 95% CI: 0.736-0.898, P < 0.001) and its gene expression in PBCs (AUC: 0.742, 95% CI: 0.647-0.836, P < 0.001) to distinguish subclinical atherosclerosis. The reductions in serum and PBCs expression levels of Klotho in CKD patients are independently associated with the presence of for subclinical atherosclerosis. Further research exploring whether therapeutic approaches to maintain or elevate Klotho could reduce the impact of CVD in CKD patients is warranted.


Assuntos
Aterosclerose/diagnóstico , Glucuronidase/metabolismo , Insuficiência Renal Crônica/fisiopatologia , Idoso , Índice Tornozelo-Braço , Aterosclerose/metabolismo , Biomarcadores/sangue , Doenças Cardiovasculares/complicações , Espessura Intima-Media Carotídea , Estudos Transversais , Feminino , Expressão Gênica/genética , Glucuronidase/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Insuficiência Renal Crônica/complicações , Fatores de Risco , Índice de Gravidade de Doença , Espanha/epidemiologia , Transcriptoma/genética
4.
Sci Rep ; 11(1): 15090, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301962

RESUMO

The klotho gene encodes a transmembrane protein αKlotho that interacts with a fibroblast growth factor (FGF) receptor in renal tubular epithelial cells and functions as a co-receptor for FGF23, which is an osteocytes-derived hormone. This bone-to-kidney signal promotes urinary phosphate excretion. Interestingly, αKlotho knockout mice show an accelerated aging and a shortened life span. Similarly, C. elegans lacking the αklotho homologue showed a short life span. However, the physiological basis of aging-related function of αklotho remain unclear. The αklotho-deficient vertebrate animals other than mice have been awaited as an alternative model of premature aging. We here employed zebrafish in our study and revealed that αklotho mutant zebrafish appeared to be normal at 3 months postfertilization (mpf) but eventually underwent premature death by 9 mpf, while normal zebrafish is known to survive for 42 months. We also assessed the motor ability of zebrafish in a forced swimming assay and found that αklotho mutant zebrafish displayed reduced swimming performance before their survival declined. A recent study also reported a similar finding that αklotho-deficient zebrafish exhibited a short life span and reduced spontaneous movements. Taken together, these results suggest that αKlotho mutant zebrafish show premature aging and are useful to investigate aging in vertebrates.


Assuntos
Glucuronidase/metabolismo , Longevidade/fisiologia , Peixe-Zebra/metabolismo , Envelhecimento/metabolismo , Animais , Osso e Ossos/metabolismo , Caenorhabditis elegans/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Rim/metabolismo , Camundongos , Camundongos Knockout
5.
Anticancer Res ; 41(7): 3299-3308, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230125

RESUMO

BACKGROUND/AIM: Heparanase (HPSE) is relevant to therapy resistance in many malignancies yet is largely unstudied in Hodgkin's lymphoma. Here, we investigated links between HPSE, cancer stem cell (CSC) features and radioresistance in KM-H2 and L428 Hodgkin's lymphoma cells. MATERIALS AND METHODS: Firstly, HPSE expression in unsorted and sorted CSCs was assessed. Post-irradiation, HPSE and CSC-related gene expression changes were then quantified. Clonogenic ability was investigated with and without artificial changes in HPSE expression pre and post irradiation. RESULTS: HPSE was highly expressed in L428 but barely present in KM-H2 cells. HPSE was overexpressed in sorted L428 CSCs. Irradiation induced HPSE and expression of CSC markers. High HPSE-expressing L428 cells showed higher clonogenic ability than low HPSE-expressing KM-H2 cells after irradiation. Down-regulation of HPSE in L428 cells reduced their clonogenic capability post-radiation, whilst overexpression of HPSE in KM-H2 cells increased colony formation. CONCLUSION: HPSE expression is associated with CSC features and contributes to radioresistance in Hodgkin's lymphoma cells.


Assuntos
Glucuronidase/metabolismo , Doença de Hodgkin/metabolismo , Células-Tronco Neoplásicas/metabolismo , Tolerância a Radiação/fisiologia , Adulto , Linhagem Celular Tumoral , Regulação para Baixo/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Masculino
6.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281178

RESUMO

Quercetin-3-glucuronide (Q3GA), the main phase II metabolite of quercetin (Q) in human plasma, is considered to be a more stable form of Q for transport with the bloodstream to tissues, where it can be potentially deconjugated by ß-glucuronidase (ß-Gluc) to Q aglycone, which easily enters the brain. This study evaluates the effect of lipopolysaccharide (LPS)-induced acute inflammation on ß-Gluc gene expression in the choroid plexus (ChP) and its activity in blood plasma, ChP and cerebrospinal fluid (CSF), and the concentration of Q and its phase II metabolites in blood plasma and CSF. Studies were performed on saline- and LPS-treated adult ewes (n = 40) receiving Q3GA intravenously (n = 16) and on primary rat ChP epithelial cells and human ChP epithelial papilloma cells. We observed that acute inflammation stimulated ß-Gluc activity in the ChP and blood plasma, but not in ChP epithelial cells and CSF, and did not affect Q and its phase II metabolite concentrations in plasma and CSF, except Q3GA, for which the plasma concentration was higher 30 min after administration (p < 0.05) in LPS- compared to saline-treated ewes. The lack of Q3GA deconjugation in the ChP observed under physiological and acute inflammatory conditions, however, does not exclude its possible role in the course of neurodegenerative diseases.


Assuntos
Plexo Corióideo/metabolismo , Glucuronidase/metabolismo , Quercetina/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Plexo Corióideo/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Glucuronidase/sangue , Glucuronidase/líquido cefalorraquidiano , Humanos , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Cultura Primária de Células , Quercetina/análogos & derivados , Quercetina/sangue , Quercetina/líquido cefalorraquidiano , Ratos , Ratos Wistar , Ovinos
7.
Eur J Neurosci ; 54(4): 5261-5271, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34184338

RESUMO

Fibroblast growth factor 23 (FGF23) is an endocrine growth factor and known to play a pivotal role in phosphate homeostasis. Interestingly, several studies point towards a function of FGF23 in the hypothalamus. FGF23 classically activates the FGF receptor 1 in the presence of the co-receptor αKlotho, of both gene expression in the brain was previously established. However, studies on gene and protein expression of FGF23 in the brain are scarce and have been inconsistent. Therefore, our aim was to localise FGF23 gene and protein expression in the rat brain with focus on the hypothalamus. Also, we investigated the protein expression of αKlotho. Adult rat brains were used to localise and visualise FGF23 and αKlotho protein in the hypothalamus by immunofluorescence labelling. Furthermore, western blots were used for assessing hypothalamic FGF23 protein expression. FGF23 gene expression was investigated by qPCR in punches of the arcuate nucleus, lateral hypothalamus, paraventricular nucleus, choroid plexus, ventrolateral thalamic nucleus and the ventromedial hypothalamus. Immunoreactivity for FGF23 and αKlotho protein was found in the hypothalamus, third ventricle lining and the choroid plexus. Western blot analysis of the hypothalamus confirmed the presence of FGF23. Gene expression of FGF23 was not detected, suggesting that the observed FGF23 protein is not brain-derived. Several FGF receptors are known to be present in the brain. Therefore, we conclude that the machinery for FGF23 signal transduction is present in several brain areas, indeed suggesting a role for FGF23 in the brain.


Assuntos
Fatores de Crescimento de Fibroblastos , Glucuronidase , Animais , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Glucuronidase/metabolismo , Hipotálamo/metabolismo , Ratos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo
8.
FASEB J ; 35(7): e21725, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34110636

RESUMO

Renal fibrosis leads to chronic kidney disease, which affects over 15% of the U.S. population. PAI-1 is highly upregulated in the tubulointerstitial compartment in several common nephropathies and PAI-1 global ablation affords protection from fibrogenesis in mice. The precise contribution of renal tubular PAI-1 induction to disease progression, however, is unknown and surprisingly, appears to be independent of uPA inhibition. Human renal epithelial (HK-2) cells engineered to stably overexpress PAI-1 underwent dedifferentiation (E-cadherin loss, gain of vimentin), G2/M growth arrest (increased p-Histone3, p21), and robust induction of fibronectin, collagen-1, and CCN2. These cells are also susceptible to apoptosis (elevated cleaved caspase-3, annexin-V positivity) compared to vector controls, demonstrating a previously unknown role for PAI-1 in tubular dysfunction. Persistent PAI-1 expression results in a loss of klotho expression, p53 upregulation, and increases in TGF-ßRI/II levels and SMAD3 phosphorylation. Ectopic restoration of klotho in PAI-1-transductants attenuated fibrogenesis and reversed the proliferative defects, implicating PAI-1 in klotho loss in renal disease. Genetic suppression of p53 reversed the PA1-1-driven maladaptive repair, moreover, confirming a pathogenic role for p53 upregulation in this context and uncovering a novel role for PAI-1 in promoting renal p53 signaling. TGF-ßRI inhibition also attenuated PAI-1-initiated epithelial dysfunction, independent of TGF-ß1 ligand synthesis. Thus, PAI-1 promotes tubular dysfunction via klotho reduction, p53 upregulation, and activation of the TGF-ßRI-SMAD3 axis. Since klotho is an upstream regulator of both PAI-1-mediated p53 induction and SMAD3 signaling, targeting tubular PAI-1 expression may provide a novel, multi-level approach to the therapy of CKD.


Assuntos
Células Epiteliais/metabolismo , Glucuronidase/metabolismo , Rim/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Insuficiência Renal Crônica/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular , Fibroblastos/metabolismo , Fibrose/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Fosforilação/fisiologia , Transdução de Sinais , Proteína Smad3/metabolismo , Regulação para Cima/fisiologia
9.
Biosci Rep ; 41(7)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34132790

RESUMO

During the current formidable COVID-19 pandemic, it is appealing to address ideas that may invoke therapeutic interventions. Clotting disorders are well recognized in patients infected with severe acute respiratory syndrome (SARS) caused by a novel coronavirus (SARS-CoV-2), which lead to severe complications that worsen the prognosis in these subjects. Increasing evidence implicate Heparan sulfate proteoglycans (HSPGs) and Heparanase in various diseases and pathologies, including hypercoagulability states. Moreover, HSPGs and Heparanase are involved in several viral infections, in which they enhance cell entry and release of the viruses. Herein we discuss the molecular involvement of HSPGs and heparanase in SARS-CoV-2 infection, namely cell entry and release, and the accompanied coagulopathy complications, which assumedly could be blocked by heparanase inhibitors such as Heparin and Pixatimod.


Assuntos
Transtornos da Coagulação Sanguínea/etiologia , Coagulação Sanguínea , COVID-19/complicações , Glucuronidase/metabolismo , SARS-CoV-2/fisiologia , Animais , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/metabolismo , COVID-19/sangue , COVID-19/metabolismo , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/etiologia , Coagulação Intravascular Disseminada/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Internalização do Vírus
10.
Nat Commun ; 12(1): 3825, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158479

RESUMO

Klotho-VS heterozygosity (KL-VShet) is associated with reduced risk of Alzheimer's disease (AD). However, whether KL-VShet is associated with lower levels of pathologic tau, i.e., the key AD pathology driving neurodegeneration and cognitive decline, is unknown. Here, we assessed the interaction between KL-VShet and levels of beta-amyloid, a key driver of tau pathology, on the levels of PET-assessed neurofibrillary tau in 551 controls and patients across the AD continuum. KL-VShet showed lower cross-sectional and longitudinal increase in tau-PET per unit increase in amyloid-PET when compared to that of non-carriers. This association of KL-VShet on tau-PET was stronger in Klotho mRNA-expressing brain regions mapped onto a gene expression atlas. KL-VShet was related to better memory functions in amyloid-positive participants and this association was mediated by lower tau-PET. Amyloid-PET levels did not differ between KL-VShet carriers versus non-carriers. Together, our findings provide evidence to suggest a protective role of KL-VShet against amyloid-related tau pathology and tau-related memory impairments in elderly humans at risk of AD dementia.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Glucuronidase/metabolismo , Transtornos da Memória/metabolismo , Proteínas tau/metabolismo , Idoso , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Expressão Gênica , Glucuronidase/genética , Heterozigoto , Humanos , Masculino , Transtornos da Memória/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica
11.
PLoS One ; 16(6): e0252607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086738

RESUMO

Heparan sulfate proteoglycans (HSPGs) consist of a core protein with side chains of the glycosaminoglycan heparan sulfate (HS). We have previously identified (i) the HSPGs syndecan-1 (SDC1), and collagen type XVIII (COL18) inside mouse and human islet beta cells, and (ii) a critical role for HS in beta cell survival and protection from reactive oxygen species (ROS). The objective of this study was to investigate whether endoplasmic reticulum (ER) stress contributes to oxidative stress and type 2 diabetes (T2D) by depleting beta cell HSPGs/HS. A rapid loss of intra-islet/beta cell HSPGs, HS and heparanase (HPSE, an HS-degrading enzyme) accompanied upregulation of islet ER stress gene expression in both young T2D-prone db/db and Akita Ins2WT/C96Y mice. In MIN6 beta cells, HSPGs, HS and HPSE were reduced following treatment with pharmacological inducers of ER stress (thapsigargin or tunicamycin). Treatment of young db/db mice with Tauroursodeoxycholic acid (TUDCA), a chemical protein folding chaperone that relieves ER stress, improved glycemic control and increased intra-islet HSPG/HS. In vitro, HS replacement with heparin (a highly sulfated HS analogue) significantly increased the survival of wild-type and db/db beta cells and restored their resistance to hydrogen peroxide-induced death. We conclude that ER stress inhibits the synthesis/maturation of HSPG core proteins which are essential for HS assembly, thereby exacerbating oxidative stress and promoting beta cell failure. Diminished intracellular HSPGs/HS represent a previously unrecognized critical link bridging ER stress, oxidative stress and beta cell failure in T2D.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Estresse do Retículo Endoplasmático , Proteoglicanas de Heparan Sulfato/metabolismo , Estresse Oxidativo , Fatores Ativadores da Transcrição/genética , Fatores Ativadores da Transcrição/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Glucuronidase/genética , Glucuronidase/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Lactonas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Sesquiterpenos/farmacologia , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Regulação para Cima/efeitos dos fármacos
12.
PLoS One ; 16(6): e0252554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34061900

RESUMO

Acute kidney injury (AKI) is associated with a very high mortality and an increased risk for progression to chronic kidney disease (CKD). Ischemia-reperfusion injury (IRI) is a model for AKI, which results in tubular damage, dysfunction of the mitochondria and autophagy, and in decreased cellular nicotinamide adenine dinucleotide (NAD+) with progressing fibrosis resulting in CKD. NAD+ is a co-enzyme for several proteins, including the NAD+ dependent sirtuins. NAD+ augmentation, e.g. by use of its precursor nicotinamide riboside (NR), improves mitochondrial homeostasis and organismal metabolism in many species. In the present investigation the effects of prophylactic administration of NR on IRI-induced AKI were studied in the rat. Bilateral IRI reduced kidney tissue NAD+, caused tubular damage, reduced α-Klotho (klotho), and altered autophagy flux. AKI initiated progression to CKD, as shown by induced profibrotic Periostin (postn) and Inhibin subunit beta-A, (activin A / Inhba), both 24 hours and 14 days after surgery. NR restored tissue NAD+ to that of the sham group, increased autophagy (reduced p62) and sirtuin1 (Sirt1) but did not ameliorate renal tubular damage and profibrotic genes in the 24 hours and 14 days IRI models. AKI induced NAD+ depletion and impaired autophagy, while augmentation of NAD+ by NR restored tissue NAD+ and increased autophagy, possibly serving as a protective response. However, prophylactic administration of NR did not ameliorate tubular damage of the IRI rats nor rescued the initiation of fibrosis in the long-term AKI to CKD model, which is a pivotal event in CKD pathogenesis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/etiologia , NAD/metabolismo , Niacinamida/análogos & derivados , Substâncias Protetoras/administração & dosagem , Compostos de Piridínio/administração & dosagem , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Injúria Renal Aguda/complicações , Injúria Renal Aguda/metabolismo , Animais , Autofagia/efeitos dos fármacos , Progressão da Doença , Fibrose , Glucuronidase/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Mitocôndrias/metabolismo , Niacinamida/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Wistar , Insuficiência Renal Crônica/etiologia , Sirtuína 1/metabolismo , Resultado do Tratamento
13.
Cancer Sci ; 112(9): 3491-3506, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34036683

RESUMO

Temozolomide (TMZ) resistance is the main challenge in the management of glioma patients. Heparanase can mediate the secretion and function of exosomes, which are considered to be a promising molecular delivery system for cancer therapy. Therefore, this study aimed to investigate whether heparanase-mediated delivery of exosomes was related to TMZ resistance of glioma. Heparanase was upregulated in TMZ-resistant glioma cells, and overexpression of heparanase led to increased resistance of U87 cells to TMZ. Knockdown of heparanase led to increased sensitivity of TMZ-resistant U251 cells (U251R) cells to TMZ. Heparanase promoted the secretion of exosomes from glioma cells, and coculture with exosomes derived from heparanase knockdown U251R cells partly restored the sensitivity of U251 cells to TMZ compared with exosomes derived from si-control transfected U251R cells. It was identified by circular RNA microarrays that hsa_circ_0042003 was upregulated in exosomes derived from U251R, which could be positively regulated by heparanase. U251R cell-derived exosomal hsa_circ_0042003 conferred the resistance of U251 cells to TMZ. In vivo studies also showed that U251R cell-derived exosomes induced resistance of U251 cells to TMZ, and the combination of tail-injected exosomal si-heparanase or exosomal si-hsa_circ_0042003 and intraperitoneal TMZ applied to nude mice abolished TMZ resistance. Heparanase mediated the transfer of exosomal hsa_circ_0042003 from TMZ-resistant glioma cells to drug-sensitive cells, which contributed to the chemoresistance of glioma to TMZ.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Exossomos/metabolismo , Glioma/tratamento farmacológico , Glucuronidase/metabolismo , RNA Circular/metabolismo , Via Secretória/genética , Temozolomida/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Glioma/sangue , Glioma/patologia , Glucuronidase/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Circular/genética , Transfecção , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Mol Cell Biochem ; 476(10): 3551-3561, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34014438

RESUMO

Vascular calcification is one of the most common effects of macrovascular complications in patients in aging with chronic kidney disease and diabetes. Previous studies showed that HOTAIR attenuated vascular calcification via the Wnt/ß-catenin-signaling pathway, yet the molecular mechanism has not been fully elucidated. This study aimed to identify the explicit molecular mechanism underlying HOTAIR regulated vascular calcification. In the phosphate (Pi)-induced calcification model of human aortic smooth muscle cells (HASMCs), we investigated whether HOTAIR was involved in the regulation of miR-126. The luciferase reporter was used to examine the effect of HOTAIR on miR-126 and miR-126 on Klotho 3'-UTR. Furthermore, we overexpressed Klotho to verify the regulation of Klotho on SIRT1, as well as their roles in mediating Pi-induced calcification in HASMCs via the Wnt/ß-catenin signaling pathway. Finally, the results were verified in an in vivo mice calcification model. Overexpression of HOTAIR reduced the expression of miR-126 in Pi-induced HASMCs. Additionally, knockdown of miR-126 increased SIRT1 expression by regulating Klotho expression. An increased level of Klotho inhibited Wnt/ß-catenin signaling pathway, which eventually attenuated Pi-induced HASMCs calcification. Luciferase reporter assay revealed that HOTAIR targeted miR-126 and miR-126 could directly target Klotho. Eventually, HOTAIR overexpression reversed Pi-induced calcium calcification in vivo mouse models. This study demonstrated that HOTAIR overexpression attenuated Pi-induced calcification by regulating the miR-126/Klotho/SIRT1 axis, thereby inhibiting the Wnt/ß-catenin signaling pathway. It provides new potential target genes for the clinical treatment of vascular calcification.


Assuntos
Glucuronidase/metabolismo , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Sirtuína 1/metabolismo , Calcificação Vascular/metabolismo , Via de Sinalização Wnt , Animais , Linhagem Celular , Glucuronidase/genética , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , MicroRNAs/genética , RNA Longo não Codificante/genética , Sirtuína 1/genética , Calcificação Vascular/genética , Calcificação Vascular/patologia
15.
Elife ; 102021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33876724

RESUMO

Aging is accompanied by disrupted information flow, resulting from accumulation of molecular mistakes. These mistakes ultimately give rise to debilitating disorders including skeletal muscle wasting, or sarcopenia. To derive a global metric of growing 'disorderliness' of aging muscle, we employed a statistical physics approach to estimate the state parameter, entropy, as a function of genes associated with hallmarks of aging. Escalating network entropy reached an inflection point at old age, while structural and functional alterations progressed into oldest-old age. To probe the potential for restoration of molecular 'order' and reversal of the sarcopenic phenotype, we systemically overexpressed the longevity protein, Klotho, via AAV. Klotho overexpression modulated genes representing all hallmarks of aging in old and oldest-old mice, but pathway enrichment revealed directions of changes were, for many genes, age-dependent. Functional improvements were also age-dependent. Klotho improved strength in old mice, but failed to induce benefits beyond the entropic tipping point.


Assuntos
Envelhecimento/metabolismo , Glucuronidase/metabolismo , Músculo Esquelético/metabolismo , Sarcopenia/metabolismo , Fatores Etários , Envelhecimento/genética , Envelhecimento/patologia , Animais , Dependovirus/genética , Dependovirus/metabolismo , Feminino , Regulação da Expressão Gênica , Terapia Genética , Vetores Genéticos , Glucuronidase/genética , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Força Muscular , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Recuperação de Função Fisiológica , Sarcopenia/genética , Sarcopenia/fisiopatologia , Sarcopenia/terapia , Transcriptoma
16.
PLoS One ; 16(4): e0250666, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33891667

RESUMO

The anti-aging gene, klotho, has been identified as a multi-functional humoral factor and is implicated in multiple biological processes. However, the effects of klotho on podocyte injury in diabetic nephropathy are poorly understood. Thus, the current study aims to investigate the renoprotective effects of klotho against podocyte injury in diabetic nephropathy. We examined lipid accumulation and klotho expression in the kidneys of diabetic patients and animals. We stimulated cultured mouse podocytes with palmitate to induce lipotoxicity-mediated podocyte injury with or without recombinant klotho. Klotho level was decreased in podocytes of lipid-accumulated obese diabetic kidneys and palmitate-treated mouse podocytes. Palmitate-treated podocytes showed increased apoptosis, intracellular ROS, ER stress, inflammation, and fibrosis, and these were significantly attenuated by klotho administration. Klotho treatment restored palmitate-induced downregulation of the antioxidant molecules, Nrf2, Keap1, and SOD1. Klotho inhibited the phosphorylation of FOXO3a, promoted its nuclear translocation, and then upregulated MnSOD expression. In addition, klotho administration attenuated palmitate-induced cytoskeleton changes, decreased nephrin expression, and increased TRPC6 expression, eventually improving podocyte albumin permeability. These results suggest that klotho administration prevents palmitate-induced functional and morphological podocyte injuries, and this may indicate that klotho is a potential therapeutic agent for the treatment of podocyte injury in obese diabetic nephropathy.


Assuntos
Apoptose/efeitos dos fármacos , Nefropatias Diabéticas/patologia , Glucuronidase/farmacologia , Palmitatos/farmacologia , Animais , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Glucuronidase/genética , Glucuronidase/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos , Camundongos Obesos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Podócitos/citologia , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Canal de Cátion TRPC6/genética , Canal de Cátion TRPC6/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
Semin Thromb Hemost ; 47(3): 240-253, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33794549

RESUMO

Cell surface proteoglycans are important constituents of the glycocalyx and participate in cell-cell and cell-extracellular matrix (ECM) interactions, enzyme activation and inhibition, and multiple signaling routes, thereby regulating cell proliferation, survival, adhesion, migration, and differentiation. Heparanase, the sole mammalian heparan sulfate degrading endoglycosidase, acts as an "activator" of HS proteoglycans, thus regulating tissue hemostasis. Heparanase is a multifaceted enzyme that together with heparan sulfate, primarily syndecan-1, drives signal transduction, immune cell activation, exosome formation, autophagy, and gene transcription via enzymatic and nonenzymatic activities. An important feature is the ability of heparanase to stimulate syndecan-1 shedding, thereby impacting cell behavior both locally and distally from its cell of origin. Heparanase releases a myriad of HS-bound growth factors, cytokines, and chemokines that are sequestered by heparan sulfate in the glycocalyx and ECM. Collectively, the heparan sulfate-heparanase axis plays pivotal roles in creating a permissive environment for cell proliferation, differentiation, and function, often resulting in the pathogenesis of diseases such as cancer, inflammation, endotheliitis, kidney dysfunction, tissue fibrosis, and viral infection.


Assuntos
Doença , Glucuronidase/metabolismo , Heparitina Sulfato/metabolismo , Humanos
18.
Semin Thromb Hemost ; 47(3): 254-260, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33794550

RESUMO

Heparanase, the only mammalian enzyme known to degrade heparan sulfate chains, affects the hemostatic system through several mechanisms. Along with the degrading effect, heparanase engenders release of syndecan-1 from the cell surface and directly enhances the activity of the blood coagulation initiator, tissue factor, in the coagulation system. Upregulation of tissue factor and release of tissue factor pathway inhibitor from the cell surface contribute to the prothrombotic effect. Tissue factor pathway inhibitor and the strongest physiological anticoagulant antithrombin are attached to the endothelial cell surface by heparan sulfate. Hence, degradation of heparan sulfate induces further release of these two natural anticoagulants from endothelial cells. Elevated heparanase procoagulant activity and heparan sulfate chain levels in plasma, demonstrated in cancer, pregnancy, oral contraceptive use, and aging, could suggest a potential mechanism for increased risk of thrombosis in these clinical settings. In contrast to the blood circulation, accumulation of heparan sulfate chains in transudate and exudate pleural effusions induces a local anticoagulant milieu. The anticoagulant effect of heparan sulfate chains in other closed spaces such as peritoneal or subdural cavities should be further investigated.


Assuntos
Glucuronidase/metabolismo , Hemostasia/fisiologia , Heparitina Sulfato/metabolismo , Humanos
19.
Biochemistry (Mosc) ; 86(2): 132-145, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33832412

RESUMO

Klotho protein affects a number of metabolic pathways essential for pathogenesis of cardio-vascular diseases and their prevention. It inhibits lipid peroxidation and inflammation, as well as prevents endothelial injury and calcification of blood vessels. Klotho decreases rigidity of blood vessels and suppresses development of the heart fibrosis. Low level of its expression is associated with a number of diseases. Cardioprotective effect of klotho is based on its ability to interact with multiple receptors and ion channels. Being a pleiotropic protein, klotho could be a useful target for therapeutic intervention in the treatment of cardio-vascular diseases. In this review we present data on pharmaceuticals that stimulate klotho expression and suggest some promising research directions.


Assuntos
Doenças Cardiovasculares/metabolismo , Glucuronidase/metabolismo , Animais , Cardiomiopatias , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Insuficiência Cardíaca , Humanos , Hipertensão , Isquemia Miocárdica
20.
Biochem Biophys Res Commun ; 557: 90-96, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33862465

RESUMO

Klotho deficiency was observed in virtually all kinds of kidney disease and is thought to play a critical role in podocyte injury. However, the underline mechanisms involved in podocyte injury remain unknown. miRNAs have diverse regulatory roles, and miR-30 family members were essential for podocyte homeostasis. Our study revealed that Klotho and miR-30s were downregulated in PAN-treated podocytes. The ectopic expression of Klotho ameliorates PAN induced podocyte apoptosis through upregulating miR-30a and downregulating Ppp3ca, Ppp3cb, Ppp3r1, and Nfact3 expression, which are the known targets of miR-30s. We also found that Klotho regulates TRPC6 via miR-30a to activate calcium/calcineurin signaling. Further, glucocorticoid (Dexamethasone, DEX) was found to sustain Klotho and miR-30a levels during PAN treatment in vitro. Eventually, in rats, PAN treatment substantially downregulated Klotho and miR-30a levels, lead to podocyte injury and increased proteinuria. The transfer of exogenous Klotho to podocytes of PAN-treated rats could increase miR-30a expression, reduce TRPC6 expression, and also ameliorated podocyte injury and proteinuria. In conclusion, Klotho, acting on miR-30s, which directly regulates its target genes, contributes to podocyte apoptosis induced by PAN. It is a novel mechanism underlying PAN-induced podocyte injury.


Assuntos
Glucuronidase/metabolismo , Nefropatias/metabolismo , MicroRNAs/metabolismo , Podócitos/metabolismo , Canal de Cátion TRPC6/metabolismo , Animais , Sinalização do Cálcio , Células Cultivadas , Dexametasona/farmacologia , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Nefropatias/genética , Nefropatias/patologia , Masculino , MicroRNAs/genética , Podócitos/efeitos dos fármacos , Podócitos/patologia , Puromicina Aminonucleosídeo/farmacologia , Ratos , Ratos Wistar
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