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1.
Circ Res ; 126(8): 1007-1023, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32098592

RESUMO

RATIONALE: Excessive Ang II (angiotensin II) levels lead to a profibrotic and hypertrophic milieu that produces deleterious remodeling and dysfunction in hypertension-associated heart failure. Agents that disrupt Ang II-induced cardiac dysfunction may have clinical utility in the treatment of hypertension-associated heart failure. OBJECTIVE: We have examined the potential effect of celastrol-a bioactive compound derived from the Celastraceae family-on Ang II-induced cardiac dysfunction. METHODS AND RESULTS: In rat primary cardiomyocytes and H9C2 (rat cardiomyocyte-like H9C2) cells, celastrol attenuates Ang II-induced cellular hypertrophy and fibrotic responses. Proteome microarrays, surface plasmon resonance, competitive binding assays, and molecular simulation were used to identify the molecular target of celastrol. Our data showed that celastrol directly binds to and inhibits STAT (signal transducer and activator of transcription)-3 phosphorylation and nuclear translocation. Functional tests demonstrated that the protection of celastrol is afforded through targeting STAT3. Overexpression of STAT3 dampens the effect of celastrol by partially rescuing STAT3 activity. Finally, we investigated the in vivo effect of celastrol treatment in mice challenged with Ang II and in the transverse aortic constriction model. We show that celastrol administration protected heart function in Ang II-challenged and transverse aortic constriction-challenged mice by inhibiting cardiac fibrosis and hypertrophy. CONCLUSIONS: Our studies show that celastrol inhibits Ang II-induced cardiac dysfunction by inhibiting STAT3 activity.


Assuntos
Angiotensina II/toxicidade , Sistemas de Liberação de Medicamentos/métodos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Triterpenos/administração & dosagem , Remodelação Ventricular/efeitos dos fármacos , Animais , Linhagem Celular , Células HEK293 , Humanos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Triterpenos Pentacíclicos , Estrutura Terciária de Proteína , Distribuição Aleatória , Ratos , Fator de Transcrição STAT3/química , Tripterygium , Triterpenos/química , Remodelação Ventricular/fisiologia
2.
Diabet Med ; 33(8): 1112-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26499911

RESUMO

AIM: The burden of Type 2 diabetes is alarmingly high in South Asia, a region that has many genetically diverse ethnic populations. Genome-wide association studies (GWAS) conducted largely in European populations have identified a number of loci predisposing to Type 2 diabetes risk, however, the relevance of such genetic loci in many South Asian sub-ethnicities remains elusive. The aim of this study was to replicate 49 single nucleotide polymorphisms (SNPs) previously identified through GWAS in Punjabis living in Pakistan. METHODS: We examined the association of 49 SNPs in 853 Type 2 diabetes cases and 1945 controls using additive logistic regression models after adjusting for age and gender. RESULTS: Of the 49 SNPs investigated, eight showed a nominal association (P < 0.05) that also remained significant after controlling for the false discovery rate. The most significant association was found for rs7903146 at the TCF7L2 locus. For a per unit increase in the risk score comprising of all the 49 SNPs, the odds ratio in association with Type 2 diabetes risk was 1.16 (95% CI 1.13-1.19, P < 2.0E-16). CONCLUSION: These results suggest that some Type 2 diabetes susceptibility loci are shared between Europeans and Punjabis living in Pakistan.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/genética , Adulto , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Paquistão , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
3.
Haemophilia ; 22(2): 199-207, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26822547

RESUMO

INTRODUCTION: Bleeding from the reproductive tract in women is a natural event, generally occurring with menstruation and childbirth. Women with an underlying bleeding disorder may experience heavy menstrual bleeding (HMB) and thereby, unacceptable blood loss. Up to 20% of US women with abnormal uterine bleeding and a normal gynaecological exam may have an underlying bleeding disorder corresponding to almost 2-3 million American women. These females face many obstacles in achieving optimum medical care for their problems. A haematologist may not evaluate these women as they are treated symptomatically. Recognition of an underlying bleeding disorder is not straightforward and many come to attention after serious bleeding events. Although mortality from HMB is uncommon, the true burden of HMB is its impact on health-related quality of life. To address these issues, women with HMB require a comprehensive approach to their care. METHODS: These reasons compelled us to institute a multidisciplinary Young Women's Blood Disorders (YWBD) Program at our institution. RESULTS: Herein, we describe the process of developing this program involving paediatric haematology, adolescent medicine and paediatric/adolescent gynaecology, and the expertise of a laboratory coagulationist, a nutritionist and nursing professionals. We also describe our experience with patient selection, the role of each specialty in the program, our approach to testing, the coordination of care and overall management of this patient population. Lastly, we propose metrics that could be followed in justifying the support of such a program. CONCLUSIONS: There is a growing need to offer comprehensive care to women with HMB and blood disorders. The YWBD program at our institution appears to be successful in delivering optimal care to young women affected with HMB.

5.
Emerg Radiol ; 23(2): 105-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26585759

RESUMO

The pregnant abdominal trauma patient presents a unique diagnostic challenge. This study aimed to evaluate the accuracy of abdominal sonography for the detection of clinically important injuries in pregnant abdominal trauma patients. A retrospective review was performed of a trauma center database from 2001 to 2011. Medical records were reviewed to determine initial abdominal imaging test results and clinical course. Sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound for detection of traumatic injury were calculated. Of 19,128 patients with suspected abdominal trauma, 385 (2 %) were pregnant. Of these, 372 (97 %) received ultrasound as the initial abdominal imaging test. All 13 pregnant patients who did not receive ultrasound received abdominal CT. Seven pregnant patients underwent both ultrasound and CT. Seven ultrasound examinations were positive, leading to one therapeutic Cesarean section and one laparotomy. One ultrasound was considered false positive (no injury was seen on subsequent CT). There were 365 negative ultrasound examinations. Of these, 364 were true negative (no abdominal injury subsequently found). One ultrasound was considered false negative (a large fetal subchorionic hemorrhage seen on subsequent dedicated obstetrical ultrasound). Sensitivity and positive predictive value were 85.7 %. Specificity and negative predictive value were 99.7 %. Abdominal sonography is an effective and sufficient imaging examination in pregnant abdominal trauma patients. When performed as part of the initial assessment using an abbreviated trauma protocol with brief modifications for pregnancy, ultrasound minimizes diagnostic delay, obviates radiation risk, and provides high sensitivity for injury in the pregnant population.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Complicações na Gravidez/diagnóstico por imagem , Ultrassonografia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
J Mol Cell Cardiol ; 79: 1-12, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25444713

RESUMO

Obesity and increased free fatty acid (FFA) level are tightly linked, leading to the development of cardiovascular disorders. Curcumin is a natural product from Curcuma longa with multiple bioactivities and is known to have cardioprotective effects in several cellular and animal models. The current study was designed to evaluate the cardioprotective effects of curcumin and demonstrate the underlying mechanism in FFA-induced cardiac injury. Using cell culture studies and high fat in vivo model, we explored the mechanistic basis of anti-inflammatory and antioxidant activities of curcumin. We observed that palmitate (PA) treatment in cardiac derived H9C2 cells induced a marked increase in reactive oxygen species, inflammation, apoptosis and hypertrophy. All of these changes were effectively suppressed by curcumin treatment. In addition, oral administration of curcumin at 50mg/kg completely suppressed high fat diet-induced oxidative stress, inflammation, apoptosis, fibrosis, hypertrophy and tissue remodeling in mice. The beneficial actions of curcumin are closely associated with its ability to increase Nrf2 expression and inhibit NF-κB activation. Thus, both in vitro and in vivo studies showed a promising role of curcumin as a cardioprotective agent against palmitate and high fat diet mediated cardiac dysfunction. We indicated the regulatory roles of Nrf2 and NF-κB in obesity-induced heart injury, and suggested that they may be important therapeutic targets in the treatment of obesity-related disorders.


Assuntos
Cardiotônicos/uso terapêutico , Curcumina/farmacologia , Ácidos Graxos não Esterificados/efeitos adversos , Miocárdio/metabolismo , Miocárdio/patologia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cardiomegalia/complicações , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Cardiotônicos/farmacologia , Linhagem Celular , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Dieta Hiperlipídica , Fibrose , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Palmitatos/efeitos adversos , Ratos , Espécies Reativas de Oxigênio/metabolismo
7.
Stem Cells ; 32(6): 1649-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24496952

RESUMO

Human bone marrow mesenchymal progenitor cells (MPCs) are multipotent cells that play an essential role in endogenous repair and the maintenance of the stem cell niche. We have recently shown that high levels of glucose, conditions mimicking diabetes, cause impairment of MPCs, resulting in enhanced adipogenesis and suppression of osteogenesis. This implies that diabetes may lead to reduced endogenous repair mechanisms through altering the differentiation potential of MPCs and, consequently, disrupting the stem cell niche. Phenotypic alterations in the bone marrow of long-term diabetic patients closely resemble this observation. Here, we show that high levels of glucose selectively enhance autogenous Wnt11 expression in MPCs to stimulate adipogenesis through the Wnt/protein kinase C noncanonical pathway. This novel mechanism may account for increased bone marrow adipogenesis, severe bone loss, and reduced vascular stem cells leading to chronic secondary complications of diabetes.


Assuntos
Adipogenia/efeitos dos fármacos , Glucose/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Antígeno AC133 , Idoso , Angiopoietina-2/metabolismo , Animais , Antígenos CD/metabolismo , Medula Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Glicoproteínas/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Modelos Biológicos , Peptídeos/metabolismo , Proteína Quinase C/metabolismo , Ratos Sprague-Dawley , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
8.
Haemophilia ; 21(1): 124-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25545302

RESUMO

Rare bleeding disorders (RBDs) comprise 3-5% of all congenital bleeding disorders. They can evade typical coagulation screening tests and there is a poor correlation between laboratory results and bleeding phenotype. Thromboelastography (TEG) measures coagulation globally in whole blood samples. The aims of this study were to evaluate the utility of TEG as an adjunct to the routine screening tests employed for the diagnosis of RBDs and to correlate TEG results with the bleeding phenotype in RBDs. TEG parameters and clot kinetics were compared to bleeding phenotypes (asymptomatic, mild, moderate and severe) in 26 RBD patients and 30 normal controls. Clot kinetics correlated strongly with RBDs and with the severity of bleeding phenotype with mean maximum rate of thrombus generation (MRTG) 15.4 mm min(-1) in controls vs. 6.0 in RBDs (P < 0.0001, Wilcoxin). The mean MRTG was 7.7 in mildly symptomatic, 5.5 in moderately symptomatic and 4.1 in severely symptomatic patients (P < 0.0001, Kruskal-Wallis). Disorders that are often missed by conventional screening tests, dysfibrinogenaemia and platelet disorders displayed a distinctive TEG curve with markedly decreased maximum amplitude (MA) and low MRTG values. Factor XIII and PAI deficient patients displayed increased fibrinolysis in addition to low MRTGs. All patients with RBDs, but none of the normal controls, had abnormal clot kinetics suggesting that TEG may be an effective screening test for RBDs.


Assuntos
Transtornos da Coagulação Sanguínea/diagnóstico , Testes de Coagulação Sanguínea/métodos , Hemorragia/sangue , Tromboelastografia/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fenótipo , Doenças Raras , Estudos Retrospectivos
9.
Pediatr Res ; 75(3): 381-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24296797

RESUMO

BACKGROUND: Infantile hemangioma (IH) is the most common tumor of infancy. The first-line therapy for IH is propranolol, a nonselective ß-adrenergic receptor antagonist. However, mechanisms for the therapeutic effect of propranolol and regrowth of IH following cessation of treatment in some cases are not clear. We have recently shown that IH arises from multipotent stem cells. Whether IH stem cells are responsive to propranolol and are selectively targeted is unknown, and this is the focus of this study. METHODS: IH stem cells were exposed to propranolol and were assayed for cellular and molecular alterations. We used endothelial cells (ECs) as controls and bone marrow-derived mesenchymal progenitor cells (bm-MPCs) as normal stem/progenitor counterparts to determine selectivity. RESULTS: Our results show that propranolol significantly reduced IH stem cell growth but failed to induce caspase-3 activation. Normal bm-MPCs and mature ECs showed maintained or increased caspase-3 activation and significantly reduced cyclin-D1 levels. We further show that IH stem cells may escape apoptosis by inducing antiapoptotic pathways. CONCLUSION: This study reveals that propranolol does not induce apoptosis in IH stem cells, which is in contrast with the result for ECs. Escape from apoptosis in IH stem cells may involve induction of antiapoptotic pathways.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Proliferação de Células/efeitos dos fármacos , Hemangioma/tratamento farmacológico , Células-Tronco Multipotentes/efeitos dos fármacos , Propranolol/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Contagem de Células , Ciclina D1/metabolismo , Hemangioma/etiologia , Humanos , Lactente , Reação em Cadeia da Polimerase em Tempo Real
10.
East Mediterr Health J ; 19 Suppl 3: S147-51, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24995738

RESUMO

The aim of this study was to investigate trends in road traffic crashes (RTCs) managed by an emergency service, Rescue 1122, in 2011 in Punjab, Pakistan. RTC data were collected from 35 districts of Punjab and reviewed retrospectively. Data analysis revealed that the service responded to 12 969 RTC emergencies during August 2011 (Ramadan), compared with an average of 11 573 RTCs per month from January to August 2011. The younger age group (11-27 years) was victims in 29% of RTCs; 39% were due to speeding and 43% occurred in peak rush hours (14:00-18:00) before iftar (breakfast).Results of the study showed that Rescue 1122 faced more RTCs during Ramadan compared with the preceding months. Road safety is an important public health issue in Pakistan. Although there have been great improvements in roads in the past few years, much work needs to be done to deal with mounting trends in RTCs. Public awareness, political will and stringent law enforcement are key factors.

11.
Exp Mol Pathol ; 94(1): 126-36, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23047069

RESUMO

Infantile hemangioma is a benign vascular tumor that exhibits a unique yet predictable lifecycle of rapid proliferation followed by spontaneous regression. Recent studies have identified that insulin-like growth factor-2 (IGF2), a fetal mitogen, is highly expressed during the proliferative phase of hemangioma growth. Since hemangiomas arise from CD133+ stem cells, high levels of IGF2 may regulate the activity of the stem cells and therefore, hemangioma growth. The aim of this study was to understand the functional significance of elevated IGF2 in hemangiomas. We show that IGF2 localizes to the CD133+ cells in hemangioma specimens. We, therefore, hypothesized that IGF2 may be regulating the plasticity of hemangioma stem cells. To test our hypothesis, we used CD133-selected cells from hemangiomas to knockdown the expression of IGF2. We found that IGF2 is a mitogen for hemangioma stem cells and prevents leptin induction and full terminal differentiation of hemangioma stem cells into adipocytes. We also show that IGF2 does not alter the initial commitment phase. These findings implicate an important role of IGF2 in expanding hemangioma stem cells and preventing terminal adipocyte differentiation.


Assuntos
Adipócitos/fisiologia , Adipogenia , Hemangioma/metabolismo , Hemangioma/patologia , Fator de Crescimento Insulin-Like II/metabolismo , Leptina/metabolismo , Células-Tronco Neoplásicas/fisiologia , Antígeno AC133 , Adipócitos/metabolismo , Antígenos CD/análise , Diferenciação Celular , Proliferação de Células , Glicoproteínas/análise , Hemangioma/irrigação sanguínea , Humanos , Fator de Crescimento Insulin-Like II/genética , Mitógenos , Células-Tronco Neoplásicas/metabolismo , Peptídeos/análise , Interferência de RNA , RNA Interferente Pequeno , Células Tumorais Cultivadas
12.
Cardiovasc Diabetol ; 11: 37, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22524626

RESUMO

Long standing diabetes leads to structural and functional alterations in both the micro- and the macro-vasculature. Vascular endothelial cells (ECs) are the primary target of the hyperglycemia-induced adverse effects. Vascular stem cells that give rise to endothelial progenitor cells (EPCs) and mesenchymal progenitor cells (MPCs) represent an attractive target for cell therapy for diabetic patients. A number of studies have reported EPC dysfunction as a novel participant in the culmination of the diabetic complications. The controversy behind the identity of EPCs and the similarity between these progenitor cells to hematopoietic cells has led to conflicting results. MPCs, on the other hand, have not been examined for a potential role in the pathogenesis of the complications. These multipotent cells, however, do show a therapeutic role. In this article, we summarize the vascular changes that occur in diabetic complications highlighting some of the common features, the key findings that illustrate an important role of vascular stem cells (VSCs) in the pathogenesis of chronic diabetic complications, and provide mechanisms by which these cells can be used for therapy.


Assuntos
Angiopatias Diabéticas/cirurgia , Células Endoteliais/transplante , Endotélio Vascular/fisiopatologia , Transplante de Células-Tronco Mesenquimais , Músculo Liso Vascular/fisiopatologia , Neovascularização Fisiológica , Animais , Glicemia/metabolismo , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/patologia , Angiopatias Diabéticas/fisiopatologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Regeneração , Resultado do Tratamento
13.
Exp Mol Pathol ; 93(2): 264-72, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22565125

RESUMO

Infantile hemangioma is a benign vascular tumor, characterized by a unique life cycle consisting of rapid growth and spontaneous regression. Three distinct phases (proliferating, involuting, and involuted) take place over the course of approximately 5-8 years, with specific cell types defining each separate phase. The origin of the cells comprising hemangiomas has been deliberated over since the late 1800s. We have recently provided experimental evidence that hemangiomas arise from multipotent stem cells. These hemangioma stem cells that give rise to the endothelial cells are also the essential source of adipocytes during hemangioma involution. The molecular mechanisms that regulate the differentiation of the hemangioma stem cells remain unclear. Although recent studies have elucidated a number of signaling pathways underlying hemangioma pathogenesis, many unanswered questions remain. Herein, we review the unique cellular composition of infantile hemangioma, as well as some of the signaling pathways active within hemangioma-genesis. Understanding the mechanisms behind changes in cellular fate throughout the hemangioma growth pattern will not only provide insight into the stem cell population that resides within the tumor, but will help to establish more effective eradicating therapies.


Assuntos
Endotélio Vascular/patologia , Hemangioma Capilar/patologia , Células-Tronco Multipotentes/patologia , Síndromes Neoplásicas Hereditárias/patologia , Neovascularização Patológica/patologia , Biomarcadores Tumorais/metabolismo , Endotélio Vascular/metabolismo , Hemangioma Capilar/terapia , Humanos , Células-Tronco Multipotentes/metabolismo , Síndromes Neoplásicas Hereditárias/terapia , Neovascularização Patológica/metabolismo , Transdução de Sinais
14.
Can J Neurol Sci ; 39(6): 821-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23041404

RESUMO

BACKGROUND: Hemangioblastomas are benign vascular tumors of the central nervous system that occur sporadically or in association with von Hippel-Lindau disease. These tumors are characteristically composed of a dense capillary network with intervening stromal/interstitial cells. To date, the histogenesis of hemangioblastoma remains unclear. We hypothesize that hemangioblastomas arise from a defective mesodermal stem cell, which gives rise to the atypical vasculature. METHODS: To test our hypothesis, we have characterized the cellular composition of hemangioblastomas by immunophenotyping pluripotent and committed stem cells and vascular endothelial cells. RESULTS: Our findings show that hemangioblastoma endothelial cells are positive for CD133, a stem and progenitor cell marker. Vascular endothelial cells also expressed nuclear Oct4. In addition to the endothelium, both CD133 and Oct4 were present in stromal and perivascular cells. Interestingly, neither the endothelium nor the stromal cells expressed Sox2 or Nanog suggesting a committed stem cell phenotype. CONCLUSIONS: From these findings, we believe that hemangioblastoma stromal cells are committed stem cells producing both vascular cell types. The findings also show an unusual CD133-positive endothelial phenotype in hemangioblastoma.


Assuntos
Neoplasias Cerebelares/patologia , Hemangioblastoma/patologia , Células-Tronco/fisiologia , Células Estromais/fisiologia , Antígeno AC133 , Actinas/metabolismo , Adulto , Antígenos CD/metabolismo , Diferenciação Celular/fisiologia , Feminino , Transportador de Glucose Tipo 1/metabolismo , Glicoproteínas/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/metabolismo , Peptídeos/metabolismo , Fosfopiruvato Hidratase/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fatores de Transcrição SOXB1/metabolismo
15.
Commun Biol ; 5(1): 1145, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307522

RESUMO

Diabetes affects select organs such as the eyes, kidney, heart, and brain. Our recent studies show that diabetes also enhances adipogenesis in the bone marrow and reduces the number of marrow-resident vascular regenerative stem cells. In the current study, we have performed a detailed spatio-temporal examination to identify the early changes that are induced by diabetes in the bone marrow. Here we show that short-term diabetes causes structural and molecular changes in the marrow, including enhanced adipogenesis in tibiae of mice, prior to stem cell depletion. This enhanced adipogenesis was associated with suppressed transforming growth factor-beta (TGFB) signaling. Using human bone marrow-derived mesenchymal progenitor cells, we show that TGFB pathway suppresses adipogenic differentiation through TGFB-activated kinase 1 (TAK1). These findings may inform the development of novel therapeutic targets for patients with diabetes to restore regenerative stem cell function.


Assuntos
Diabetes Mellitus , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Medula Óssea/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Células-Tronco Mesenquimais/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Fatores de Crescimento Transformadores/metabolismo
16.
Hypertension ; 79(9): 2028-2041, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35862110

RESUMO

BACKGROUND: Elevated Ang II (angiotensin II) level leads to a range of conditions, including hypertensive kidney disease. Recent evidences indicate that FGFR1 (fibroblast growth factor receptor 1) signaling may be involved in kidney injuries. In this study, we determined whether Ang II alters FGFR1 signaling to mediate renal dysfunction. METHODS: Human archival kidney samples from patients with or without hypertension were examined. Multiple genetic and pharmacological approaches were used to investigate FGFR1-mediated signaling in tubular epithelial NRK-52E cells in response to Ang II stimulation. C57BL/6 mice were infused with Ang II for 28 days to develop hypertensive kidney disease. Mice were treated with either adeno-associated virus expressing FGFR1 shRNA or FGFR1 inhibitor AZD4547. RESULTS: Kidney specimens from subjects with hypertension and mice challenged with Ang II have increased FGFR1 activity in renal epithelial cells. Renal epithelial cells in culture initiate extracellular matrix programming in response to Ang II, through the activation of FGFR1, which is independent of both AT1R (angiotensin II receptor type 1) and AT2R (angiotensin II receptor type 2). The RNA sequencing analysis indicated that disrupting FGFR1 suppresses Ang II-induced fibrogenic responses in epithelial cells. Mechanistically, Ang II-activated FGFR1 leads to STAT3 (signal transducer and activator of transcription 3) activation, which is responsible for fibrogenic factor expression in kidneys. In the mouse model of hypertensive kidney disease, genetic knockdown of FGFR1 or pharmacological inhibition of its activity protected kidneys from dysfunction and fibrosis upon Ang II challenge. CONCLUSIONS: Our studies uncover a novel mechanism causing renal fibrosis in hypertension and indicate FGFR1 as a potential target to preserve renal function and integrity.


Assuntos
Hipertensão Renal , Hipertensão , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Células Epiteliais/metabolismo , Fibrose , Humanos , Hipertensão/metabolismo , Hipertensão Renal/metabolismo , Rim/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nefrite , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores de Angiotensina/metabolismo
17.
Adv Sci (Weinh) ; 9(31): e2202590, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36180407

RESUMO

Diabetes manifests as chronic inflammation and leads to the development diabetic cardiomyopathy (DCM). Targeting key proteins in inflammatory signaling may provide new therapy for DCM. In this study, the authors explore the pharmacological effects and mechanisms of Schisandrin B (Sch B), a natural compound with anti-inflammatory activity against DCM. It is shown that Sch B prevents high-level glucose (HG)-induced hypertrophic and fibrotic responses in cultured cardiomyocytes. RNA sequencing and inflammatory qPCR microarray show that Sch B mainly affects myeloid differentiation primary response 88 (MyD88)-dependent inflammatory gene expression in HG-challenged cardiomyocytes. Further studies indicate that Sch B directly binds to and inhibits MyD88 activation, but does not alter MyD88-independent Toll-like receptor signaling in vivo and in vitro. Inhibiting or silencing MyD88 is associated with reduced levels of HG-induced inflammatory cytokines and myocardial injuries in vitro. Treatment of type 1 and type 2 diabetic mice with Sch B protects heart function, reduces myocardial injuries, and decreases secretion of inflammatory cytokines. Cardiomyocyte-specific MyD88 knockout also protects mice against cardiac inflammation and injury in type 1 diabetic mice. In conclusion, these studies show that cardiomyocyte MyD88 plays an apathogenetic role in DCM and Sch B specifically targets MyD88 to reduce inflammatory DCM.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Animais , Camundongos , Citocinas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/prevenção & controle , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/uso terapêutico
18.
Int Immunopharmacol ; 112: 109218, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36116148

RESUMO

BACKGROUND: Kidney damage is a frequent event in the course of hypertension. Recent researches highlighted a critical role of non-hemodynamic activities of angiotensin II (Ang II) in hypertension-associated kidney fibrosis and inflammation. These activities are mediated through toll-like receptors (TLRs) but the mechanisms by which Ang II links TLRs to downstream inflammatory and fibrogenic responses is not fully known. In this study, we investigated the role of TLR adapter protein called myeloid differentiation primary-response protein-88 (MyD88) as the potential link. METHODS: C57BL/6 mice were administered Ang II by micro-osmotic pump infusion for 4 weeks to develop nephropathy. Mice were treated with small-molecule MyD88 inhibitor LM8. In vitro, MyD88 was blocked using siRNA or LM8 in Ang II-challenged renal tubular epithelial cells. RESULTS: We show that MyD88 is mainly located in tubular epithelial cells and Ang II increases the interaction between TLR4 and MyD88. This interaction activates MAPKs and nuclear factor-κB (NF-κB), leading to increased production of inflammatory and fibrogenic factors. Inhibition of MyD88 by siRNA or selective inhibitor LM8 supresses MyD88-TLR4 interaction, NF-κB activation, and elaboration of inflammatory cytokines and fibrosis-associated factors. These protective actions resulted in decreased renal pathological changes and preserved renal function in LM8-treated hypertensive mice, without affecting hypertension. CONCLUSION: These results demonstrate that Ang II induces inflammation and fibrosis in renal tubular epithelial cells through MyD88 and present MyD88 as a potential point of intervention for hypertension-associated kidney disease.


Assuntos
Hipertensão Renal , Hipertensão , Camundongos , Animais , Angiotensina II/metabolismo , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais , Hipertensão Renal/induzido quimicamente , Hipertensão Renal/tratamento farmacológico , Hipertensão Renal/metabolismo , Rim/patologia , Fibrose , Citocinas/metabolismo , Inflamação/metabolismo , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo
19.
J Clin Invest ; 118(7): 2592-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18535669

RESUMO

Infantile hemangioma is a benign endothelial tumor composed of disorganized blood vessels. It exhibits a unique life cycle of rapid postnatal growth followed by slow regression to a fibrofatty residuum. Here, we have reported the isolation of multipotential stem cells from hemangioma tissue that give rise to hemangioma-like lesions in immunodeficient mice. Cells were isolated based on expression of the stem cell marker CD133 and expanded from single cells as clonal populations. The CD133-selected cells generated human blood vessels 7 days after implantation in immunodeficient mice. Cell retrieval experiments showed the cells could again form vessels when transplanted into secondary recipients. The human vessels expressed GLUT-1 and merosin, immunodiagnostic markers for infantile hemangioma. Two months after implantation, the number of blood vessels diminished and human adipocytes became evident. Lentiviral expression of GFP was used to confirm that the hemangioma-derived cells formed the blood vessels and adipocytes in the immunodeficient mice. Thus, when transplanted into immunodeficient mice, hemangioma-derived cells recapitulated the unique evolution of infantile hemangioma--the formation of blood vessels followed by involution to fatty tissue. In summary, this study identifies a stem cell as the cellular origin of infantile hemangioma and describes for what we believe is the first time an animal model for this common tumor of infancy.


Assuntos
Modelos Animais de Doenças , Hemangioma/patologia , Células-Tronco Multipotentes/transplante , Células-Tronco Neoplásicas/transplante , Adipócitos/química , Adipócitos/patologia , Animais , Antígenos Nucleares/análise , Antígenos de Superfície/análise , Vasos Sanguíneos/química , Vasos Sanguíneos/patologia , Proteínas de Transporte , Diferenciação Celular/efeitos dos fármacos , Separação Celular , Transplante de Células/efeitos adversos , Transplante de Células/métodos , Células Endoteliais/química , Células Endoteliais/patologia , Transportador de Glucose Tipo 1/análise , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Hemangioma/etiologia , Hemangioma/metabolismo , Humanos , Lactente , Laminina/análise , Masculino , Camundongos , Camundongos Nus , Células-Tronco Multipotentes/química , Células-Tronco Multipotentes/patologia , Células-Tronco Neoplásicas/química , Células-Tronco Neoplásicas/patologia , Perilipina-1 , Fosfoproteínas/análise , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Receptores de Fatores de Crescimento do Endotélio Vascular/análise , Transfecção
20.
Braz J Biol ; 81(2): 387-391, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32490897

RESUMO

Poor storage conditions provide favorable environment to stored grain pests for their growth. The bio-pesticides are the best alternatives to synthetic pesticides. Present study was conducted to compare toxicity of Rubus fruticosus and Valeriana jatamansi against granary weevil, Sitophilus granarius and subsequent changes in enzyme activity responsible for grain damage. In current research 5 g of R. fruticosus fruit and V. jatamansi rhizome powders were tested separately against S. granarius, in 50 g wheat whole grains for seven days in comparison with the control. The enzymatic activity of malate dehydrogenase and α-amylase was observed in the cellular extracts of S. granarius. The insects were crushed and homogenized in phosphate-buffer solution and centrifuged at 10000 rpm for 5 minutes. For the enzymatic measurement supernatant was tested; the spectrophotometer was adjusted at 340 nm. The reagents were mixed and incubated at 25 °C for five minutes. The cuvettes were placed in the experimental and reference sites of spectrophotometer and recorded the change in absorbance for 3-4 minutes. There was 5.60% and 14.92% reduction in the activity of malate dehydrogenase in R. fruticosus and V. jatamansi, treated insects, respectively. The alpha amylase enzyme activity was 6.82% reduced and 63.63% increase in R. fruticosus and V. jatamansi, treated insects, respectively. Present study addresses that both plant powders are effective against granary weevil by altering enzyme activities so both the plant powders can be used as bio-pesticides against the stored grains pests.


Assuntos
Rubus , Valeriana , Gorgulhos , Animais , Malato Desidrogenase , alfa-Amilases
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