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1.
J Am Coll Cardiol ; 83(7): 726-738, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38355242

RESUMO

BACKGROUND: The molecular mechanisms underlying Fontan-associated liver disease (FALD) remain largely unknown. OBJECTIVES: This study aimed to assess intrahepatic transcriptomic differences among patients with FALD according to the degree of liver fibrosis and clinical outcomes. METHODS: This retrospective cohort study included adults with the Fontan circulation. Baseline clinical, laboratory, imaging, and hemodynamic data as well as a composite clinical outcome (CCO) were extracted from medical records. Patients were classified into early or advanced fibrosis. RNA was isolated from formalin-fixed paraffin-embedded liver biopsy samples; RNA libraries were constructed with the use of an rRNA depletion method and sequenced on an Illumina Novaseq 6000. Differential gene expression and gene ontology analyses were performed with the use of DESeq2 and Metascape. RESULTS: A total of 106 patients (48% male, median age 31 years [IQR: 11.3 years]) were included. Those with advanced fibrosis had higher B-type natriuretic peptide levels and Fontan, mean pulmonary artery, and capillary wedge pressures. The CCO was present in 23 patients (22%) and was not predicted by advanced liver fibrosis, right ventricular morphology, presence of aortopulmonary collaterals, or Fontan pressures on multivariable analysis. Samples with advanced fibrosis had 228 upregulated genes compared with early fibrosis. Samples with the CCO had 894 upregulated genes compared with those without the CCO. A total of 136 upregulated genes were identified in both comparisons and were enriched in cellular response to cytokine stimulus or oxidative stress, VEGFA-VEGFR2 signaling pathway, TGF-ß signaling pathway, and vasculature development. CONCLUSIONS: Patients with FALD and advanced fibrosis or the CCO exhibited upregulated genes related to inflammation, congestion, and angiogenesis.


Assuntos
Técnica de Fontan , Cardiopatias Congênitas , Hepatopatias , Adulto , Humanos , Masculino , Feminino , Estudos Retrospectivos , Cirrose Hepática/genética , Cirrose Hepática/patologia , Hepatopatias/genética , Hepatopatias/cirurgia , Fibrose , Perfilação da Expressão Gênica , RNA , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/cirurgia
2.
Cells ; 12(20)2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37887278

RESUMO

Glucocorticoid-induced bone loss is a severe and toxic effect of long-term therapy with glucocorticoids, which are currently prescribed for millions of people worldwide. Previous studies have uncovered that glucocorticoids reciprocally converted osteoblast lineage cells into endothelial-like cells to cause bone loss and showed that the modulations of Foxc2 and Osterix were the causative factors that drove this harmful transition of osteoblast lineage cells. Here, we find that the inhibition of aurora kinase A halts this transition and prevents glucocorticoid-induced bone loss. We find that aurora A interacts with the glucocorticoid receptor and show that this interaction is required for glucocorticoids to modulate Foxc2 and Osterix. Together, we identify a new potential approach to counteracting unwanted transitions of osteoblast lineage cells in glucocorticoid treatment and may provide a novel strategy for ameliorating glucocorticoid-induced bone loss.


Assuntos
Aurora Quinase A , Doenças Ósseas Metabólicas , Glucocorticoides , Glucocorticoides/efeitos adversos , Osteoblastos , Receptores de Glucocorticoides , Animais
3.
medRxiv ; 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37333414

RESUMO

Background: The molecular mechanisms underlying Fontan associated liver disease (FALD) remain largely unknown. We aimed to assess intrahepatic transcriptomic differences among patients with FALD according to the degree of liver fibrosis and clinical outcomes. Methods: This retrospective cohort study included adults with the Fontan circulation at the Ahmanson/UCLA Adult Congenital Heart Disease Center. Clinical, laboratory, imaging and hemodynamic data prior to the liver biopsy were extracted from medical records. Patients were classified into early (F1-F2) or advanced fibrosis (F3-F4). RNA was isolated from formalin-fixed paraffin embedded liver biopsy samples; RNA libraries were constructed using rRNA depletion method and sequencing was performed on Illumina Novaseq 6000. Differential gene expression and gene ontology analyses were carried out using DESeq2 and Metascape. Medical records were comprehensively reviewed for a composite clinical outcome which included decompensated cirrhosis, hepatocellular carcinoma, liver transplantation, protein-losing enteropathy, chronic kidney disease stage 4 or higher, or death. Results: Patients with advanced fibrosis had higher serum BNP levels and Fontan, mean pulmonary artery and capillary wedge pressures. The composite clinical outcome was present in 23 patients (22%) and was predicted by age at Fontan, right ventricular morphology and presence of aortopulmonary collaterals on multivariable analysis. Samples with advanced fibrosis had 228 up-regulated genes compared to early fibrosis. Samples with the composite clinical outcome had 894 up-regulated genes compared to those without it. A total of 136 up-regulated genes were identified in both comparisons and these genes were enriched in cellular response to cytokine stimulus, response to oxidative stress, VEGFA-VEGFR2 signaling pathway, TGF-beta signaling pathway, and vasculature development. Conclusions: Patients with FALD and advanced liver fibrosis or the composite clinical outcome exhibit up-regulated genes including pathways related to inflammation, congestion, and angiogenesis. This adds further insight into FALD pathophysiology.

4.
Stem Cells ; 40(10): 932-948, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-35896368

RESUMO

Adipose-derived cells (ADCs) from white adipose tissue are promising stem cell candidates because of their large regenerative reserves and the potential for cardiac regeneration. However, given the heterogeneity of ADC and its unsolved mechanisms of cardiac acquisition, ADC-cardiac transition efficiency remains low. In this study, we explored the heterogeneity of ADCs and the cellular kinetics of 39,432 single-cell transcriptomes along the leukemia inhibitory factor (LIF)-induced ADC-cardiac transition. We identified distinct ADC subpopulations that reacted differentially to LIF when entering the cardiomyogenic program, further demonstrating that ADC-myogenesis is time-dependent and initiates from transient changes in nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. At later stages, pseudotime analysis of ADCs navigated a trajectory with 2 branches corresponding to activated myofibroblast or cardiomyocyte-like cells. Our findings offer a high-resolution dissection of ADC heterogeneity and cell fate during ADC-cardiac transition, thus providing new insights into potential cardiac stem cells.


Assuntos
Miócitos Cardíacos , Fator 2 Relacionado a NF-E2 , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/farmacologia , RNA-Seq , Diferenciação Celular/genética
5.
J Oral Maxillofac Surg ; 79(5): 1069-1073, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33290724

RESUMO

PURPOSE: Atherosclerotic plaques develop as a result of a low-grade, chronic, systemic inflammatory response to the injury of endothelial cells arising from lipid deposition within the intima. Increased white blood cell count (WBCC) is both a validated "biologic marker" of the extent of this inflammatory process and a key participant in the development of subsequent atherosclerotic ischemic heart disease manifesting as myocardial infarction. We sought to determine if calcified carotid artery plaque (CCAP) on a panoramic image (PI), also a validated risk indicator of future myocardial infarction, is associated with increased WBCC. PATIENTS AND METHODS: We retrospectively evaluated the PI and medical records of White male military veterans aged 55 years and older treated by a VA dental service. Established were 2 cohorts of patients, 50 having plaques (CCAP+) and 50 without plaques (CCAP-). Predictor variable was CCAP+; outcome variable was WBCC. Bootstrapping analysis determined the differences in mean WBCCs between groups. Statistical significance set at ≤ 0.05. RESULTS: The study group, (mean age 74; range 59 to 91 years) demonstrated a mean WBCC of 8,062 per mm3. The control group, (mean age 72 range; 57 to 94) evidenced a mean WBCC of 7,058 per mm3. Bootstrapping analysis of WBCC values demonstrated a significant (P = .012) difference (95% confidence interval of difference of mean, -806, 742; observed effect size, 1004) between groups. CONCLUSIONS: The presence of CCAP demonstrated on PIs of older Caucasian men is associated with elevated WBCC. Concomitant presence of CCAP on PI and increased WBCC (≥7,800 per mm3) amplifies need for medical consultation before intravenous anesthesia and maxillofacial surgical procedures.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Placa Aterosclerótica , Idoso , Idoso de 80 Anos ou mais , Células Endoteliais , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Radiografia Panorâmica , Estudos Retrospectivos , Fatores de Risco
6.
J Mol Biol ; 432(7): 2030-2041, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32061928

RESUMO

AIMS: Several signaling pathways contribute to endothelial-mesenchymal transitions and vascular calcification, including bone morphogenetic protein (BMP) and transforming growth factor (TGF) ß signaling. The transcription factor homeobox D3 (Hoxd3) is known to regulate an invasive endothelial phenotype, and the aim of the study is to determine if HOXD3 modulates BMP and TGFß signaling in the endothelium. METHODS AND RESEARCH: We report that the endothelium with high BMP activity due to the loss of BMP inhibitor matrix Gla protein (MGP) shows induction of Hoxd3. HOXD3 is part of a BMP-triggered cascade. When activated by BMP9, activin receptor-like kinase (ALK) 1 induces HOXD3 expression. Hoxd3 promoter is a direct target of phosphorylated (p) SMAD1, a mediator of BMP signaling. High BMP activity further results in enhanced TGFß signaling due to induction of TGFß1 and its receptor, ALK5. This is mediated by HOXD3, which directly targets the Tgfb1 promoter. Finally, TGFß1 and BMP9 stimulate the expression of MGP, which limits the enhanced ALK1 induction by counteracting BMP4. The cascade of BMP9-HOXD3-TGFß also affects Notch signaling and angiogenesis through induction of Notch ligand Jagged 2 and suppression of Notch ligand delta-like 4 (Dll4). CONCLUSION: The results suggest that HOXD3 is a novel link between BMP9/ALK1 and TGFß1/ALK5 signaling. TRANSLATIONAL PERSPECTIVE: BMP and TGFß signaling are instrumental in vascular disease such as vascular calcification and atherosclerosis. This study demonstrated a novel type of cross talk between endothelial BMP and TGFß signaling as mediated by HOXD3. The results provide a possible therapeutic approach to control dysfunctional BMP and TGFß signaling by regulating HOXD3.


Assuntos
Receptores de Activinas Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Neovascularização Fisiológica , Proteínas/fisiologia , Receptores Notch/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Receptores de Activinas Tipo II/genética , Animais , Proteínas de Ligação a DNA/genética , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Receptores Notch/genética , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética
7.
Cell Signal ; 68: 109537, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31927035

RESUMO

Notch signaling and Sry-box (Sox) family transcriptional factors both play critical roles in endothelial cell (EC) differentiation in vascularization. Recent studies have shown that excessive Notch signaling induces Sox2 to cause cerebral arteriovenous malformations (AVMs). Here, we examine human pulmonary AVMs and find no induction of Sox2. Results of epigenetic studies also show less alteration of Sox2-DNA binding in pulmonary AVMs than in cerebral AVMs. We identify high expression of ski-interacting protein (Skip) in brain ECs, a Notch-associated chromatin-modifying protein that is lacking in lung ECs. Knockdown of Skip abolished Notch-induction of Sox2 in brain ECs, while restoration of Skip in lung ECs enabled Notch-mediated Sox2 induction. The results suggest that Skip is a key factor for induction of Sox2 in cerebral AVMs.


Assuntos
Malformações Arteriovenosas Intracranianas/metabolismo , Coativadores de Receptor Nuclear/metabolismo , Receptores Notch/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , DNA/metabolismo , Células Endoteliais/metabolismo , Humanos , Malformações Arteriovenosas Intracranianas/patologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Modelos Biológicos , Ligação Proteica , Proteínas/metabolismo , Artéria Pulmonar/patologia
8.
Molecules ; 24(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640276

RESUMO

Recently polymer encapsulated surface-enhanced-Raman-scattering (SERS) probes with internal noble metal core-shell structure has found growing applications in biomedical applications. Here we studied the SERS spectra of Au@Ag-4MBA@PVP (4MBA: 4-mercaptobenzoic acid; PVP: polyvinylpyrrolidone) plasmonic nanoparticles produced from a chemical reduction method. By linking the atomic force microscope (AFM) with the homebuilt confocal Raman spectrometer thus to use AFM images as guidance, we realized the measurement of the SERS spectra from separated nanoparticles. We investigated the cases for single nanoparticles and for dimer structures and report several observed results including SERS spectra linearly scaled with laser power, abrupt boosting and abnormal shape changing of SERS spectra for dimer structures. Based on the finite element method simulation, we explained the observed ratio of SERS signals between the dimer structure and the single nanoparticle, and attributed the observed abnormal spectra to the photothermal effect of these plasmonic nanoparticles. Our study provides valuable guidance for choosing appropriate laser power when applying similar SERS probes to image biological cells.


Assuntos
Benzoatos/química , Ouro/química , Povidona/química , Prata/química , Compostos de Sulfidrila/química , Análise de Elementos Finitos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia de Força Atômica , Modelos Químicos , Análise Espectral Raman , Ressonância de Plasmônio de Superfície
9.
Chemistry ; 25(49): 11560-11565, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31297891

RESUMO

It remains challenging to rationally synthesize iron/nitrogen-doped carbon (Fe/N-C) catalysts with rich Fe-Nx atomic active sites for improved oxygen reduction reaction (ORR) electrocatalysis. A highly efficient Fe/N-C catalyst, which has been synthesized through a spatial isolation strategy, is reported. Derived from bioinspired polydopamine (PDA)-based hybrid microsphere precursors, it is a multifunctional carrier that loads atomically dispersed Fe3+ /Zn2+ ions through coordination interactions and N-rich melamine through electrostatic attraction and covalent bonding. The Zn2+ ions and melamine in the precursor efficiently isolate Fe3+ atoms upon pyrolysis to form rich Fe-Nx atomic active sites, and generate abundant micropores during high-temperature treatment; as a consequence, the resultant Fe-N/C catalyst contains rich catalytically active Fe-Nx sites and a hierarchical porous structure. The catalyst exhibits improved ORR activity that is superior to and close to that of Pt/C in alkaline and acidic solutions, respectively.

10.
Arterioscler Thromb Vasc Biol ; 38(9): 2016-2027, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30026271

RESUMO

Objective- The objective of this study was to determine the basis of resistance to atherosclerosis of inbred mouse strain BALB/cJ. Approach and Results- BALB/cJ mice carry a naturally occurring null mutation of the gene encoding the transcription factor Zhx2, and genetic analyses suggested that this may confer resistance to atherosclerosis. On a hyperlipidemic low-density lipoprotein receptor null background, BALB/cJ mice carrying the mutant allele for Zhx2 exhibited up to a 10-fold reduction in lesion size as compared with an isogenic strain carrying the wild-type allele. Several lines of evidence, including bone marrow transplantation studies, indicate that this effect of Zhx2 is mediated, in part, by monocytes/macrophages although nonbone marrow-derived pathways are clearly involved as well. Both in culture and in atherosclerotic lesions, macrophages from Zhx2 null mice exhibited substantially increased apoptosis. Zhx2 null macrophages were also enriched for M2 markers. Effects of Zhx2 on proliferation and other bone marrow-derived cells, such as lymphocytes, were at most modest. Expression microarray analyses identified >1000 differentially expressed transcripts between Zhx2 wild-type and null macrophages. To identify the global targets of Zhx2, we performed ChIP-seq (chromatin immunoprecipitation sequencing) studies with the macrophage cell line RAW264.7. The ChIP-seq peaks overlapped significantly with gene expression and together suggested roles for transcriptional repression and apoptosis. Conclusions- A mutation of Zhx2 carried in BALB/cJ mice is responsible in large part for its relative resistance to atherosclerosis. Our results indicate that Zhx2 promotes macrophage survival and proinflammatory functions in atherosclerotic lesions, thereby contributing to lesion growth.


Assuntos
Apoptose , Aterosclerose/fisiopatologia , Proteínas de Homeodomínio/fisiologia , Macrófagos/fisiologia , Fatores de Transcrição/fisiologia , Dedos de Zinco/fisiologia , Animais , Proliferação de Células , Modelos Animais de Doenças , Expressão Gênica , Proteínas de Homeodomínio/genética , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fatores de Transcrição/genética , Dedos de Zinco/genética
11.
J Cell Biol ; 216(10): 3369-3385, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28838957

RESUMO

The vascular endothelium is critical for induction of appropriate lineage differentiation in organogenesis. In this study, we report that dysfunctional pulmonary endothelium, resulting from the loss of matrix Gla protein (MGP), causes ectopic hepatic differentiation in the pulmonary epithelium. We demonstrate uncontrolled induction of the hepatic growth factor (HGF) caused by dysregulated cross talk between pulmonary endothelium and epithelium in Mgp-null lungs. Elevated HGF induced hepatocyte nuclear factor 4 α (Hnf4a), which competed with NK2 homeobox 1 (Nkx2.1) for binding to forkhead box A2 (Foxa2) to drive hepatic differentiation in Mgp-null airway progenitor cells. Limiting endothelial HGF reduced Hnf4a, abolished interference of Hnf4a with Foxa2, and reduced hepatic differentiation in Mgp-null lungs. Together, our results suggest that endothelial-epithelial interactions, maintained by MGP, are essential in pulmonary cell differentiation.


Assuntos
Comunicação Celular , Diferenciação Celular , Endotélio Vascular/metabolismo , Células Epiteliais/metabolismo , Mucosa Respiratória/metabolismo , Animais , Endotélio Vascular/citologia , Células Epiteliais/citologia , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Fator 3-beta Nuclear de Hepatócito/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Camundongos , Camundongos Knockout , Proteínas/genética , Proteínas/metabolismo , Mucosa Respiratória/citologia
12.
Biol Trace Elem Res ; 175(2): 331-338, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27339255

RESUMO

The current study was conducted to investigate the effects of dietary zinc oxide (ZnO) on the antioxidant capacity, small intestine development, and jejunal gene expression in weaned piglets. Ninety-six 21-day-old piglets were randomly assigned to three dietary treatments. Each treatment had eight replicates with four piglets per replicate. The piglets were fed either control diet (control) or control diet supplemented with in-feed antibiotics (300 mg/kg chlortetracycline and 60 mg/kg colistin sulfate) or pharmacological doses of ZnO (3000 mg/kg). The experiment lasted 4 weeks. Blood samples were collected at days 14 and 28, while intestinal samples were harvested at day 28 of the experiment. Dietary high doses of ZnO supplementation significantly increased the body weight (BW) at day 14 and average daily gain (ADG) of days 1 to 14 in weaned piglets, when compared to control group (P < 0.05). The incidence of diarrhea of piglets fed ZnO-supplemented diets, at either days 1 to 14, days 14 to 28, or the overall experimental period, was significantly decreased in comparison with those in other groups (P < 0.05). Supplementation with ZnO increased the villus height of the duodenum and ileum in weaned piglets and decreased the crypt depth of the duodenum, when compared to the other groups (P < 0.05). Dietary ZnO supplementation decreased the malondialdehyde (MDA) concentration at either day 14 or day 28, but increased total superoxide dismutase (T-SOD) at day 14, when compared to that in the control (P < 0.05). ZnO supplementation upregulated the messenger RNA (mRNA) expression of zonula occludens-1 (ZO-1) and occludin in the jejunum mucosa of weaned piglets, compared to those in the control (P < 0.05). The pro-inflammatory cytokine interleukin-lß (IL-1ß) mRNA expression in the jejunum mucosa was downregulated in the ZnO-supplemented group, compared with the control (P < 0.05). Both in-feed antibiotics and ZnO supplementation decreased the mRNA expression of interferon-γ (IFN-γ), but increased the mRNA expression of transforming growth factor-ß (TGF-ß), in the jejunum mucosa of piglets, when compared to those in the control (P < 0.05). In summary, supplemental ZnO was effective on the prevention of post-weaning diarrhea (PWD) in weaned piglets and showed comparative growth-promoting effect on in-feed antibiotics, probably by the mechanism of improvement of the antioxidant capacity, restoration of intestinal barrier function and development, and modulation of immune functions.


Assuntos
Antioxidantes/metabolismo , Suplementos Nutricionais , Regulação da Expressão Gênica/efeitos dos fármacos , Jejuno/metabolismo , Óxido de Zinco/farmacologia , Animais , Suínos
13.
Physiol Rep ; 2(11)2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25428948

RESUMO

Diabetic nephropathy (DN) is a major complication of diabetes and the leading cause of end-stage renal disease. DN is characterized by changes in kidney structure and function but the underlying genetic and molecular factors are poorly understood. We used a mouse diversity panel to explore the genetic basis of DN traits in mice carrying the Ins2 Akita mutation. Twenty-eight Akita strains were generated by breeding this panel to DBA/2.Akita mice. Male F1 diabetic and nondiabetic littermates were evaluated for DN-related traits. Urine albumin-to-creatinine ratios (ACRs), volume and cystatin C as well as blood urea nitrogen and lipoprotein levels varied significantly among the diabetic strains. For most Akita strains, ACR values increased 2- to 6-fold over euglycemic control values. However, six strains exhibited changes in ACR exceeding 10-fold with two strains (NOD/ShiLt and CBA) showing 50- to 83- fold increases. These increases are larger than previously reported among available DN mouse models establishing these strains as useful for additional studies of renal function. ACRs correlated with cystatin C (P = 0.0286), a measure of hyperfiltration and an interstitial tubular marker associated with DN onset in humans suggesting that tubule damage as well as podocyte-stress contributed to reduced kidney function assessed by ACR. Although large changes were seen for ACRs, severe nephropathology was absent. However, glomerular hypertrophy and collagen IV content were found to vary significantly among strains suggesting a genetic basis for early onset features of DN. Our results define the range of DN phenotypes that occur among common inbred strains of mice.

14.
Am J Physiol Endocrinol Metab ; 293(6): E1656-62, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17911343

RESUMO

The islet in type 2 diabetes is characterized by an approximately 60% beta-cell deficit, increased beta-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). Human IAPP (hIAPP) but not rodent IAPP (rIAPP) forms toxic oligomers and amyloid fibrils in an aqueous environment. We previously reported that overexpression of hIAPP in transgenic rats triggered endoplasmic reticulum (ER) stress-induced apoptosis in beta-cells. In the present study, we sought to establish whether the cytotoxic effects of hIAPP depend on its propensity to oligomerize, rather than as a consequence of protein overexpression. To accomplish this, we established a novel homozygous mouse model overexpressing rIAPP at a comparable expression rate and, on the same background, as a homozygous transgenic hIAPP mouse model previously reported to develop diabetes associated with beta-cell loss. We report that by 10 wk of age hIAPP mice develop diabetes with a deficit in beta-cell mass due to increased beta-cell apoptosis. The rIAPP transgenic mice counterparts do not develop diabetes or have decreased beta-cell mass. Both rIAPP and hIAPP transgenic mice have increased expression of BiP, but only hIAPP transgenic mice have elevated ER stress markers (X-box-binding protein-1, nuclear localized CCAAT/enhancer binding-protein homologous protein, active caspase-12, and accumulation of ubiquitinated proteins). These findings indicate that the beta-cell toxic effects of hIAPP depend on the propensity of IAPP to aggregate, but not on the consequence of protein overexpression.


Assuntos
Amiloide/metabolismo , Apoptose/fisiologia , Retículo Endoplasmático/fisiologia , Células Secretoras de Insulina/metabolismo , Poliubiquitina/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Amiloide/genética , Animais , Glicemia/metabolismo , Peso Corporal , Caspase 12/metabolismo , Linhagem Celular Tumoral , Citosol/metabolismo , Proteínas de Ligação a DNA/metabolismo , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Chaperonas Moleculares/metabolismo , Proteínas Nucleares/metabolismo , Proteínas/metabolismo , Ratos , Fatores de Transcrição de Fator Regulador X , Fator de Transcrição CHOP/metabolismo , Fatores de Transcrição
15.
Ai Zheng ; 22(11): 1152-7, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-14613642

RESUMO

BACKGROUND & OBJECTIVE: The squamous cell carcinoma of tongue is one of the most common malignant tumors of oral cavity. Surgical therapy is now the mainstay of combined treatment for tongue squamous cell Carcinoma with chemotherapy and radiotherapy. The overall 5-year survival rate was about 50%. The antiangiogenesis therapy has become a new approach of the treatment of tongue carcinoma. This paper was designed to study the characteristics of endostatin expression in tongue cancer cell line (Tca8113), human embryonic epithelial cell line (ECV) and the inhibition of carcinogenesis in nude mice, xenografted with Tca8113, after transfected with recombined adenovirus (Ad/hEnd) which was cloned with human endostatin gene in EI mutated region. METHODS: (1) To determine the expression and distribution of endostatin in Tca and ECV cells transfected with Ad/hEnd using immunohistochemistry. To determine the endostatin in supernatants of Tca cells transfected with Ad/hEnd using ELISA method. To examine the characteristics of endostatin gene expression in Tca8113 and ECV cells by Western blot analysis. (2) To determine the inhibition rate of proliferation and apoptosis rate of ECV cells by WST-1 test and flow cytometry (FCM), respectively.(3) To observe the inhibition of tumor growth in xenografted nude mice with Tca8113 cells by Ad/hEnd administration. RESULTS: (1) Immunohistochemistry detection indicated that the endostatin was expressed in cytoplasm of Tca8113 cells and ECV cells transfected with Ad/hEnd. Endostatin expression in the supernatant was dose-dependent with the highest to 597 ng/ml. The expression of endostatin in Tca cells was detectable from 1 day to 7 day. Ad/hEnd inhibited ECV cell growth in dose-dependent manner. (2) FCM showed that Ad/hEnd arrested ECV cells in S and G(2) phase and induced apoptosis.(3) The tumor growth curve showed that Ad/hEnd significantly repressed xenograft tumor growth with Tca cell in nude mice; the inhibition rate on Ad/hEnd administrated groups was 45.8% in the 3rd week. CONCLUSION: Ad/hEnd expressed efficiently in Tca8113 and ECV cells. Ad/hEnd can change the cell cycle distribution of ECV cells and induce apoptosis and inhibit proliferation of ECV cells. Ad/hEnd could inhibit the growth of tongue carcinoma in xenograft nude mice.


Assuntos
Carcinoma de Células Escamosas/prevenção & controle , Endostatinas/genética , Terapia Genética , Neoplasias da Língua/prevenção & controle , Adenoviridae/genética , Animais , Western Blotting , Carcinoma de Células Escamosas/patologia , Endostatinas/análise , Citometria de Fluxo , Humanos , Camundongos , Camundongos Nus , Neoplasias da Língua/patologia , Transfecção
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