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1.
Polymers (Basel) ; 16(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38399937

RESUMO

Experimental investigations and density functional theory (DFT) calculations were carried out to study the comprehensive effect of different 3,5-heptanedioldibenzoate (HDDB) optical isomers as the internal electron donor on the catalytic performance of Ziegler-Natta catalysts. The experimental catalytic activity of HDDB has a positive correlation with the relative content of the mesomer incorporated during catalyst preparation, while the hydrogen response of HDDB displayed a negative correlation with the relative content of the mesomer. In order to apply the DFT calculation results to the macroscopic activity of the catalyst, the content of the active centers of the catalyst was analyzed. Assuming that the content of the active centers is proportional to the internal electron donor content of the catalyst, binary linear regression was carried out, which showed a good linear correlation between experimental activity data and internal electron donor content. Furthermore, the fitted activity of the single active centers aligned well with the calculated activation energies. These results revealed that the catalytic activity of polypropylene (PP) catalysts is dependent on both the active center content and the catalytic activity of an individual active center. Additionally, the lower hydrogen response of HDDB leads to a higher molecular weight of polypropylene obtained from the RS-containing catalyst compared to the SS-containing catalyst. Further study reveals that the hydrogen transfer reactions of 2,4-pentanediol dibenzoate (PDDB)/HDDB are influenced by the orientation of the methyl/ethyl groups in different isomers, which affect the activation energy differences between the hydrogen transfer reaction and the propylene insertion reaction, and finally influence the molecular weight of PP.

2.
Cytokine ; 176: 156508, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38266461

RESUMO

PURPOSE: This study aimed to investigate the expression of fibroblast growth factor 23 (FGF23) in pregnant women with preeclampsia and elucidate its role in promoting placental angiogenesis through the ERK1/2-EGR-1 signaling pathway. METHODS: Serum FGF23 levels were measured by ELISA in healthy pregnant women and patients with preeclampsia during the first, second, and third trimesters of pregnancy. Wound healing, Transwell, and tube formation assays were performed to investigate the effects of FGF23 on cell migration, invasion and tube formation. The expression of vascular endothelial growth factor A (VEGF-A) and its upstream signaling molecules, p-ERK, and EGR-1, in placental tissues was detected by RT-qPCR and western blotting. Additionally, the effect of FGF23 on VEGF-A, p-ERK, and EGR-1 expression was further explored in vitro. RESULTS: Serum FGF23 levels increased with gestational age. During the third trimester, the control group exhibited a more pronounced increase in FGF23 levels than the preeclampsia group. Administering exogenous FGF23 promoted trophoblast cell migration, invasion and enhanced tube formation in vascular endothelial cells. The expression levels of VEGF-A, p-ERK, and EGR-1 in the placental tissues were significantly lower in the preeclampsia group than in the control group. In vitro experiments confirmed that FGF23 up-regulated VEGF-A expression through the p-ERK/EGR-1 signaling pathway. CONCLUSION: The serum level of FGF23 decreased in pregnant women with preeclampsia, inhibiting the ERK1/2-EGR-1 pathway and resulting in decreased expression of VEGF-A, thereby inhibiting placental angiogenesis. This could be a potential mechanism involved in the progression of preeclampsia.


Assuntos
Pré-Eclâmpsia , Fator A de Crescimento do Endotélio Vascular , Feminino , Humanos , Gravidez , Angiogênese , Células Endoteliais/metabolismo , Sistema de Sinalização das MAP Quinases , Placenta/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Gastric Cancer ; 26(5): 721-733, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37328675

RESUMO

OBJECTIVE: To investigate the occurrence and development of gastric mucosal atrophic lesions and their histopathological characteristics. METHODS: Histopathological diagnosis and immunohistochemical staining using the EnVision two-step method were conducted on 1969 gastric mucosal atrophic lesions obtained from gastroscopic biopsy specimens. A total of 48-month three-stage endoscopic biopsy follow-ups were performed. RESULTS: When the gastric mucosal epithelium was affected by infection, chemical irritation, or immune or genetic factors, the gastric mucosal epithelium glands atrophied, the mucosa became thinner, the number of glands decreased, the intestinal epithelium progressed to metaplasia and smooth muscle fibre became hyperplasia. Such changes may lead to the proliferation and dysplasia of epithelial cells of the gastric mucosa and neoplastic hyperplasia in nature; this is referred to as gastric mucosal atrophic lesions in this study. According to this definition, the present study divided gastric mucosal atrophy into four types: (1) glandular atrophy of the lamina propria; (2) compensatory proliferative atrophy; (3) intestinal metaplasia atrophy; and (4) smooth muscle proliferative atrophy. The incidence rates of the above were 40.1% (789/1969), 14.3% (281/1969), 27.8% (547/1969) and 17.9% (352/1969), respectively. One- to 4-year follow-ups found that the changes were not significant and that the percentages of patients with disease exacerbation were 85.7% (1688/1969) and 9.8% (192/1969). The percentages of patients who developed low-grade intraepithelial neoplasia and high-grade intraepithelial neoplasia were 2.8% (55/1969) and 1.1% (21/1969), respectively; 0.7% (13/1969) of patients developed intramucosal cancer. CONCLUSION: Gastric mucosal atrophic lesions and histopathological staging are based on the morphological characteristics of gastric mucosal atrophy and the hypothesis of malignant transformation of cells during the occurrence and development of mucosal atrophy. Mastering pathological staging is beneficial to clinicians for enacting precise treatment and is important for reducing the incidence of gastric cancer.


Assuntos
Acloridria , Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Hiperplasia/patologia , Neoplasias Gástricas/patologia , Atrofia , Mucosa Gástrica/patologia , Metaplasia , Gastrite Atrófica/patologia , Infecções por Helicobacter/epidemiologia
4.
Front Oncol ; 12: 873005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785186

RESUMO

Objective: The present study aimed to investigate the histopathological types and distribution characteristics of gastric mixed tumors. Methods: Detailed histological observations, together with related immunohistochemical and genetic tests, were analyzed on 960 surgically resected samples in 6 hospitals with gastric mixed tumors from May 2017 to May 2021 in this retrospective study. Results: Epithelial-derived tumors accounted for 80.10% (769/960) of the gastric mixed tumor samples studied, and tumors of different tissue origins accounting for 10.83% (104/960), mesenchymal-derived tumors accounting for 6.25% (60/960), neuroendocrine tumors accounting for 2.40% (23/960), and lymphoma accounting for 0.42% (4/960). The histological types of gastric mixed tumors identified as most commonly were epithelial originated, followed by mixed tumors of different tissue originated, then mixed neuroendocrine, lymphoma, and mesenchymal originated in sequence. The histological number of gastric mixed tumors was ≤ 3 in 83.23% (799/960) of cases and > 4 in 16.77% (161/960) of cases. The mixed histological patterns of gastric mixed tumors were divided into three types: those with tumor cells interspersed with each other, those with incomplete fibrous tissue separation, and those without fibrous tissue separation. The gene target characteristics of gastric mixed tumors were the existence of multi-gene mutation, including human epidermalgrowth factor receptor-2 (HER2) gene amplification, key result areas (K-ras) and platelet-derived growth factor receptor alpha (PDGFRA). Conclusion: Gastric mixed tumors should be adequately sampled, each piece of tissue should be involved in the morphological proportional division of the tumor, and any independent histological component should be written into the pathological examination report.

5.
Infect Drug Resist ; 15: 3619-3629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837536

RESUMO

Objective: To investigate the occurrence and development of gastric mucosal atrophy due to Helicobacter pylori (Hp) infection and the accompanying histomorphological features. Methods: Detailed histological observations and immunohistochemical examinations were conducted via 197 endoscopic biopsies and endoscopic submucosal dissection specimens of gastric mucosal atrophic lesions with gastric Hp infection. Detailed observation was made of columnar cells in the proliferative region of the deep gastric pit and the isthmus of the gastric gland, as well as the upper part of the glandular cervix. Results: The infection of the gastric mucosa by Hp firstly led to the proliferative disorder of stem cells in the normal proliferative region of the gastric mucosa. This caused substantial propagation of cells in the proliferative region of the deep gastric pit and the isthmus of the gastric gland, as well as the upper part of the glandular cervix, as a means to replenish the damaged surface mucus cells. However, the propagation of stem cells in the proliferative region was insufficient for downward migration, and the normal physiological process of differentiation into fundic/pyloric gland cells was disrupted, resulting in glandular atrophy of the intrinsic layer of the gastric mucosa. Persistent Hp infection and disruption of stem cell proliferation in the proliferative region subsequently resulted in extensive segmental hyperplasia of the gastric mucosa and glandular atrophy of the lamina propria. Conclusion: The occurrence, development, and histomorphological features of gastric mucosal atrophy due to gastric Hp infection provide a reliable pathological basis for precise treatment by clinicians and are of great significance for controlling the development of gastric cancer.

6.
Front Med (Lausanne) ; 9: 829702, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308509

RESUMO

Objective: To discuss the histological features, pathological types, and prognosis of gastric adenocarcinoma with mucinous differentiation. Methods: Specimens of 189 cases of gastric adenocarcinoma with mucinous differentiation were collected for detailed histomorphology, immunohistochemistry, fluorescence in situ hybridization, and follow-up. Results: In accordance with the morphological and histological structural features of the cancer cells as well as the area ratio of the mucus, gastric adenocarcinoma with mucinous differentiation was divided into four types, namely pure mucinous carcinoma, intraductal papillary mucinous carcinoma, signet ring cell type mucinous carcinoma, and mixed cell type mucinous carcinoma. Based on the macroscopic types according to Bormann's classification, pure mucinous carcinoma was mostly Type I, intraductal papillary mucinous carcinoma was mostly Type II, signet ring cell type mucinous carcinoma was mostly Type IV, and mixed cell type mucinous carcinoma was mostly Type III. The 5-year survival rate was 69.2, 64.2, 0, and 31.5%, respectively. There was a statistical difference in the lymph node metastasis rate and survival rate of the four carcinoma types. The invasion features of pure mucinous carcinoma entailed penetrating corrosively in a push-in form, without blood vessel or lymphatic metastasis and with few lymphocytes and lymphatic nodules in the marginal area. Thus, there was little lymph node metastasis and invasion of nerves. The HER2 protein expression rate was 40.2% (76/189), the HER2 gene amplification detected by FISH technology was 16.9% (32/189). Conclusion: The independent histological type, four subtypes, and histopathological classification of gastric mucinous adenocarcinoma are important for the prognosis evaluation and precise treatment of this disease.

7.
J Dent Sci ; 17(1): 430-437, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35028067

RESUMO

BACKGROUND/PURPOSE: Gold metal technology improves flexibility and the resistance to cyclic fatigue of the endodontic mechanical files. This study compared the performance of ProTaper Gold (PTG) multiple file system and WaveOne Gold (WOG) single file system in simulated S-shaped root canals, which represents one of the most challenging root canal morphology. MATERIALS AND METHODS: Forty S-shaped canals (n = 20 canals/per group) in resin blocks were instrumented to an apical size of 0.25 mm using PTG and WOG Primary, respectively. The total amount of resin removal, canal transportation, centering ratio, and the degree of canal straightening were measured in Photoshop CS6 software. Statistical analysis was performed by using Mann-Whitney U-test (α = .05). RESULTS: None of the files fractured during the instrumentation. The WOG group removed significantly less amount of resin at 0, 3, 6, 7 and 9 mm from the apex (P < .05). The WOG group remained more centered in canals at 0 mm from the apex (P < .05). The PTG group showed a better centering ability and less canal transportation at 4, 5 and 6 mm from the apex (P < .05). In the coronal curvature portion, the use of WOG Primary significantly decreased curvature angle and increased radius compared with PTG instruments (P < .05). There was no significant difference between the two groups in terms of the apical curvature angle and radius change (P > .05). CONCLUSION: The WOG Primary file has a less aggressive dentin cutting and more centered apical preparation. The PTG system is more advantageous in shaping the coronal curvature of S-shaped canal.

8.
Biochem Cell Biol ; 98(2): 130-136, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31985274

RESUMO

Induction of autophagy promotes cardiomyocyte survival and confers a cardioprotective effect on acute myocardial infarction (AMI). Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse AMI. Herein, this study further investigated whether the mechanisms by which MALAT1 enhanced cardiomyocyte apoptosis involved the autophagy regulation. To address this, cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The cell apoptosis was evaluated using TUNEL staining and Western blot analysis of apoptosis-related proteins. The autophagy level was assessed using GFP-LC3 immunofluorescence and Western blot analysis of autophagy-related proteins. The results showed that H/R injury increased MALAT1 expression. Furthermore, MALAT1 overexpression significantly enhanced apoptosis and regulated autophagy of cardiomyocytes, whereas MALAT1 knockdown exerted the opposite effect. Moreover, rapamycin (an autophagy activator) effectively attenuated the MALAT1-mediated enhancement of cardiomyocyte apoptosis. Overall, our findings demonstrated that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis, at least in part, through autophagy modulation.


Assuntos
Apoptose , Autofagia , Regulação da Expressão Gênica , Miócitos Cardíacos/citologia , RNA Longo não Codificante/genética , Animais , Animais Recém-Nascidos , Proteínas de Fluorescência Verde/metabolismo , Hipóxia/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Oxigênio/metabolismo , Sirolimo/farmacologia , Transfecção
9.
Biol Res ; 52(1): 58, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783925

RESUMO

BACKGROUND: Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse acute myocardial infarction (AMI). This study aims to explore whether MALAT1 enhanced cardiomyocyte apoptosis via autophagy regulation and the underlying mechanisms of MALAT1 regulating autophagy. METHODS: Cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The autophagy level was assessed using GFP-LC3 immunofluorescence and western blot analysis of autophagy-related proteins. RNA pull-down and RNA immunoprecipitation (RIP) was performed to analyze the binding of MALAT1 and EZH2. Chromatin immunoprecipitation (ChIP) assay was performed to analyze the binding of TSC2 promoter and EZH2. The cell apoptosis was evaluated using TUNEL staining and western blot analysis of apoptosis-related proteins. RESULTS: H/R injury increased MALAT1 expression in cardiomyocytes. Furthermore, MALAT1 overexpression inhibited, whereas MALAT1 knockdown enhanced the autophagy of cardiomyocytes. Moreover, MALAT1 overexpression recruited EZH2 to TSC2 promoter regions to elevate H3K27me3 and epigenetically inhibited TSC2 transcription. Importantly, TSC2 overexpression suppressed mTOR signaling and then activated the autophagy. Further results showed that MALAT1 inhibited proliferation and enhanced apoptosis of cardiomyocytes through inhibiting TSC2 and autophagy. CONCLUSION: These findings demonstrate that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis through autophagy inhibition by regulating TSC2-mTOR signaling.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Serina-Treonina Quinases TOR/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Animais , Apoptose/genética , Autofagia/genética , Western Blotting , Imunoprecipitação da Cromatina , Imunofluorescência , Camundongos , RNA Longo não Codificante/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
10.
Biol. Res ; 52: 58, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1100910

RESUMO

BACKGROUND: Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse acute myocardial infarction (AMI). This study aims to explore whether MALAT1 enhanced cardiomyocyte apoptosis via autophagy regulation and the underlying mechanisms of MALAT1 regulating autophagy. METHODS: Cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The autophagy level was assessed using GFP-LC3 immunofluorescence and western blot analysis of autophagy-related proteins. RNA pull-down and RNA immunoprecipitation (RIP) was performed to analyze the binding of MALAT1 and EZH2. Chromatin immunoprecipitation (ChIP) assay was performed to analyze the binding of TSC2 promoter and EZH2. The cell apoptosis was evaluated using TUNEL staining and western blot analysis of apoptosis-related proteins. RESULTS: H/R injury increased MALAT1 expression in cardiomyocytes. Furthermore, MALAT1 overexpression inhibited, whereas MALAT1 knockdown enhanced the autophagy of cardiomyocytes. Moreover, MALAT1 overexpression recruited EZH2 to TSC2 promoter regions to elevate H3K27me3 and epigenetically inhibited TSC2 transcription. Importantly, TSC2 overexpression suppressed mTOR signaling and then activated the autophagy. Further results showed that MALAT1 inhibited proliferation and enhanced apoptosis of cardiomyocytes through inhibiting TSC2 and autophagy. CONCLUSION: These findings demonstrate that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis through autophagy inhibition by regulating TSC2-mTOR signaling.


Assuntos
Animais , Camundongos , Autofagia/fisiologia , Apoptose/fisiologia , Miócitos Cardíacos/metabolismo , Serina-Treonina Quinases TOR/genética , RNA Longo não Codificante/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Autofagia/genética , Transdução de Sinais , Western Blotting , Imunofluorescência , Apoptose/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Imunoprecipitação da Cromatina , Serina-Treonina Quinases TOR/metabolismo , RNA Longo não Codificante/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
11.
Biomed Pharmacother ; 106: 738-746, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29990866

RESUMO

BACKGROUND: Long noncoding RNA (LncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is involved in the development of acute myocardial infarction (AMI). However, the molecular mechanism and biological function of MALAT1 in AMI remained unclear. METHODS: The expression levels of MALAT1, miR-320 and phosphatase and tensin homolog deleted on chromosome 10 (Pten) in a mouse model of AMI and sham-operated mice were determined by quantitative real-time PCR (qRT-PCR) and western blotting, respectively. The relationships between miR-320 and MALAT1, Pten were confirmed by luciferase reporter assay. The roles of MALAT1, miR-320 and Pten in myocardial apoptosis were evaluated using Annexin V-FITC/PI double-labeled flow cytometry. Echocardiographic evaluation, serum creatine kinase MB (CK-MB) and lactate dehydrogenase (LDH), myocardial infarct size and myocardial apoptosis using terminal dexynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were used to examine the impact of MALAT1 on myocardial injury. RESULTS: MALAT1 and Pten were highly expressed, while miR-320 was suppressed in MI group. Mechanistically, MALAT1 may serve as a sponge for miR-320 to upregulate Pten, a direct target of miR-320. Moreover, MALAT1 knockdown overturned the pro-apoptotic effect of miR-320 in vitro and in vivo. CONCLUSION: MALAT1 knockdown attenuated myocardial apoptosis through suppressing Pten expression by sponging miR-320 in mouse AMI.


Assuntos
Técnicas de Silenciamento de Genes , MicroRNAs/metabolismo , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/genética , Miocárdio/enzimologia , PTEN Fosfo-Hidrolase/metabolismo , Interferência de RNA , RNA Longo não Codificante/genética , Animais , Apoptose , Células Cultivadas , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Volume Sistólico , Fatores de Tempo , Função Ventricular Esquerda , Pressão Ventricular
12.
Life Sci ; 197: 109-113, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29421437

RESUMO

AIMS: Acupuncture is frequently recommended as a complementary therapy for infertility. However, whether acupuncture can prevent early ovarian hyperstimulation syndrome has not been examined and its potential mechanisms are not well understood. MAIN METHODS: Forty rats were randomized into four groups: Control, Ovarian Stimulation Model, Acupuncture, and Human Chorionic Gonadotropin (HCG). Serum estradiol, progesterone, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels were measured by enzyme-linked immunosorbent assay. Pituitary ER mRNA and ERß expression were detected by real-time PCR and western blotting respectively. The pathology of rat ovaries were observed by light microscopy. KEY FINDINGS: We observed significantly lower estradiol levels in the Acupuncture group than in the Model group and increased LH levels in the HCG group than in Model and Acupuncture groups. Testosterone and FSH levels were significantly lower in the Acupuncture group than in the HCG group. Western blotting showed significantly lower pituitary ERß expression in the Model group than in the Control group and higher expression in the Acupuncture group than in the Model group. Real-time PCR showed lower pituitary ER mRNA expression in the Acupuncture group than in the Model group. Hematoxylin and eosin staining showed a lower proportion of atretic follicles in Acupuncture and HCG groups than in Model and Control groups. Instead, Acupuncture and HCG groups showed growing and mature follicles. SIGNIFICANCE: Our results demonstrate a relationship between acupuncture and the hypothalamic-pituitary-gonadal axis, and the potential mechanism underlying the preventative effects of acupuncture on the incidence of early ovarian hyperstimulation syndrome.


Assuntos
Terapia por Acupuntura , Estradiol/sangue , Receptor beta de Estrogênio/biossíntese , Síndrome de Hiperestimulação Ovariana , Hipófise/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Síndrome de Hiperestimulação Ovariana/sangue , Síndrome de Hiperestimulação Ovariana/terapia , Ovário/metabolismo , Progesterona/sangue , Ratos , Ratos Wistar , Testosterona/sangue
13.
Int J Clin Exp Pathol ; 6(11): 2468-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24228109

RESUMO

OBJECTIVE: To investigate whether inflammation could excessively activate platelet-derived growth factor (PDGF) signaling pathway in desoxycorticosterone (DOCA) induced salt-sensitive hypertensive rats with myocardial fibrosis (MF). METHODS: A total of 30 male SD rats underwent right nephrectomy and then bred with 1% sodium chloride and 0.1% potassium chloride for 2 weeks. These animals were randomly divided into 3 groups: CON group, DOCA group and DOCA+FAS group. Systolic blood pressure (SBP) was measured once every 2 weeks; HE staining was done to observe myocardial inflammation; immunohistochemistry was done to detect expressions of monocyte-macrophage antigen (ectodermal dysplasia 1, ED-1), PDGFRα and PDGFRß in the myocardium; real time fluorescence quantitative PCR was employed to detect the mRNA expressions of DGF-A, PDGF-B, PDGF-C, PDGF-D, PDGFRα and PDGFRß. RESULTS: The SBP in DOCA group and DOCA+FAS group increased markedly when compared with CON group (P<0.01), but there was no marked difference between DOCA group and DOCA+FAS group (P>0.05). At 14 days, in DOCA group, the myocardial inflammation was obvious, ED-1 expression increased markedly, the mRNA expressions of PDGF-A, PDGF-B, PDGF-C, PDGFRα and PDGFRß increased to different extents, protein expressions of PDGFRα and PDGFRß also elevated markedly (P<0.01), but the PDGF-D mRNA expression remained unchanged, when compared with CON group. After treatment with fasudil (a drug with anti-inflammatory activity), myocardial inflammation was significantly attenuated, mRNA expressions of PDGF-A, PDGF-B, PDGF-C and PDGFRα as well as PDGFRα protein expression reduced dramatically (P<0.01), but the mRNA and protein expressions of PDGFRß remained unchanged (P>0.05) when compared with DOCA group. CONCLUSION: In DOCA/salt induced hypertensive rats with MF, excessive activation of PDGF/PDGFR signaling pathway is involved in myocardial inflammation.


Assuntos
Desoxicorticosterona , Hipertensão/metabolismo , Miocardite/metabolismo , Miocárdio/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Cloreto de Sódio na Dieta , Animais , Pressão Sanguínea , Modelos Animais de Doenças , Fibrose , Hipertensão/etiologia , Hipertensão/genética , Hipertensão/fisiopatologia , Masculino , Miocardite/etiologia , Miocardite/genética , Miocardite/fisiopatologia , Miocárdio/patologia , Fator de Crescimento Derivado de Plaquetas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
14.
Arq. bras. cardiol ; 99(6): 1082-1091, dez. 2012. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-662371

RESUMO

FUNDAMENTO: O Imatinib é um inibidor do receptor tirosina-quinase que foi confirmada como exercendo um efeito inibidor sobre a atividade do receptor do PDGF, fator de crescimento plaquetário (PDGFRα e PDGFRβ). OBJETIVO: Investigar o efeito protetor do Imatinib na fibrose miocárdica em acetato de deoxicorticosterona (DOCA)/ratos com hipertensão induzida por sal. MÉTODOS: Sessenta ratos Sprague-Dawley machos, uninefrectomizados foram distribuídos em três grupos: ratos controles (grupo CON): grupo deoxicorticosterona (grupo DOCA); grupo deoxicorticosterona e Imatinib (grupo DOCA IMA). A Pressão Arterial Sistólica (PAS) foi medida quinzenalmente. Foi estudada a porção apical do ventrículo esquerdo. Foram empregados: coloração vermelho sirius, coloração de hematoxilina-eosina, imuno-histoquímica e ensaio de western blot. RESULTADOS: A PAS nos grupos DOCA e IMA+DOCA foi maior que no grupo CON nos dias 14 e 28. Os animais do grupo DOCA apresentaram fibrose intersticial e perivascular grave no dia 28, e as expressões de PI, PIII, tenascina-C e fibronectina foram significativamente maiores que nos grupos DOCA+IMA e CON. Quando comparados com o grupo CON, os grupos DOCA e DOCA+IMA apresentaram resposta inflamatória de tecido miocárdico e infiltração de monócitos/macrófagos de diferentes graus. As expressões proteicas do PDGF-A, PDGF-C e PDGFRα foram significativamente maiores nos grupos DOCA e DOCA+IMA que no grupo CON, mas a expressão proteica do p-PDGFRα no grupo DOCA+IMA foi menor que no DOCA. CONCLUSÃO: O Imatinib pode exercer efeitos inibitórios sobre a fibrose miocárdica em ratos com hipertensão induzida por DOCA/sal, os quais podem ser atribuídos à inibição da atividade do PDGFR-α.


BACKGROUND: Imatinib is a tyrosine kinase receptor inhibitor that has been confirmed to exert inhibitory effect on the platelet derived growth factor PDGF receptor (PDGFRα and PDGFRβ) activity. OBJECTIVE: To investigate the protective effect of imatinib on the myocardial fibrosis in deoxycorticosterone-acetate (DOCA)/salt induced hypertensive rats. METHODS: Sixty male uninephrectomized Sprague-Dawley rats were assigned to three groups: control rats (CON group); deoxycorticosterone group (DOCA group); deoxycorticosterone and imatinib group (DOCA+IMA group). Systolic blood pressure (SBP) was measured biweekly. The apical portion of the left ventricle was studied. Sirius-Red staining, Hematoxylin-Eosin staining, immunohistochemistry and Western blot assay were employed. RESULTS: SBP in the DOCA group and DOCA+IMA group was higher than that in the CON group on day 14 and 28. Animals in the DOCA group showed severe interstitial and perivascular fibrosis on day 28, and the expressions of PI, PIII, tenascin-C and fibronectin were significantly higher than those in the DOCA+IMA group and CON group. When compared with the CON group, myocardial tissue inflammatory response and monocyte/macrophage infiltration of different degrees were observed in the DOCA group and DOCA+IMA group. Protein expressions of PDGF-A, PDGF-C and PDGFRα were signiflcantly higher in the DOCA and DOCA+IMA groups than those in the CON group, but the p-PDGFRα protein expression in the DOCA+IMA group was lower than that in the DOCA group. CONCLUSION: Imatinib can exert inhibitory effects on myocardial fibrosis in DOCA/salt induced hypertensive rats, which may be attributed to the inhibition of PDGFR-α activity.


Assuntos
Animais , Masculino , Ratos , Benzamidas/farmacologia , Fibrose Endomiocárdica/tratamento farmacológico , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Western Blotting , Benzamidas/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Desoxicorticosterona , Modelos Animais de Doenças , Fibrose Endomiocárdica/patologia , Fibronectinas/análise , Fibronectinas/metabolismo , Fibrose/tratamento farmacológico , Fibrose/patologia , Hipertensão/induzido quimicamente , Hipertensão/fisiopatologia , Nefrectomia/métodos , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Ratos Sprague-Dawley , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Resultado do Tratamento , Tenascina/análise , Tenascina/metabolismo
15.
Di Yi Jun Yi Da Xue Xue Bao ; 22(1): 45-6, 2002 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-12390843

RESUMO

OBJECTIVE: To explore a new method for detecting cellular apoptosis. METHODS: Using routine electrophoresis assisted by computerized gel documentation analysis system(GDAS), apoptosis of the macrophages treated with dexamethasone was qualitatively and then quantitatively detected. RESULTS: Apoptosis occurred in the macrophages treated with dexamethasone, and DNA fragmentation of the apoptotic macrophages was visualized on 1% agarose gel electrophoresis. The apoptosis rates as determined by computerized GDAS were consistent with the results obtained from flow cytometry that showed typical apoptosis peak. CONCLUSION: Agarose gel electrophoresis assisted by computerized GDAS was relatively simple and less costly in qualitative and quantitative detection of apoptosis with precision.


Assuntos
Apoptose , Eletroforese em Gel de Ágar/métodos , Macrófagos/citologia , Animais , Células Cultivadas , Fragmentação do DNA/efeitos dos fármacos , Dexametasona/farmacologia , Processamento de Imagem Assistida por Computador , Macrófagos/efeitos dos fármacos , Camundongos
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