Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
1.
Theranostics ; 11(16): 7640-7657, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335955

RESUMO

Background: Since primary prostate cancer (PCa) can advance to the life-threatening metastatic PCa, exploring the molecular mechanisms underlying PCa metastasis is crucial for developing the novel targeted preventive strategies for decreasing the mortality of PCa. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism for gene expression and its specific roles in PCa progression remains elusive. Methods: Western blotting, quantitative real-time PCR and immunohistochemical analyses were used to detect target gene expression in PCa cells in vitro and prostate tissues from patients. RNA immunoprecipitation was conducted to analyze the specific binding of mRNA to the target protein. Migration and invasion assays were used to assess the migratory capacities of cancer cells. The correlation between target gene expression and survival rate of PCa patients was analyzed based the TCGA database. Results: We found that total RNA N6-methyladenosine (m6A) modification levels were markedly upregulated in human PCa tissues due to increased expression of methyltransferase like 3 (METTL3). Further studies revealed that the migratory and invasive capacities of PCa cells were markedly suppressed upon METTL3 knockdown. Mechanistically, METTL3 mediates m6A modification of USP4 mRNA at A2696, and m6A reader protein YTHDF2 binds to and induces degradation of USP4 mRNA by recruiting RNA-binding protein HNRNPD to the mRNA. Decrease of USP4 fails to remove the ubiquitin group from ELAVL1 protein, resulting in a reduction of ELAVL1 protein. Lastly, downregulation of ELAVL1 in turn increases ARHGDIA expression, promoting migration and invasion of PCa cells. Conclusions: Our findings highlight the role of METTL3 in modulating invasion and metastasis of PCa cells, providing insight into promising therapeutic strategies for hindering PCa progressing to deadly metastases.


Assuntos
Metiltransferases/genética , Neoplasias da Próstata/metabolismo , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica/fisiologia , Humanos , Masculino , Metiltransferases/metabolismo , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Proteases Específicas de Ubiquitina/genética
2.
Sci Total Environ ; 794: 148732, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323745

RESUMO

It has been reported that microcystin-leucine-arginine (MC-LR) can enter into the brain and demonstrate neurotoxicity resulting in learning and memory deficits. While, there is still a lack of clear understanding of the related molecular mechanisms. In this study, we observed ß-amyloid (Aß) accumulation and tau hyperphosphorylation (p-tau) at sites of Ser396 and Thr205 in mouse hippocampus and cortex, Alzheimer's disease (AD) like changes, after chronic exposure to MC-LR at different concentrations (1, 7.5, 15 and 30 µg/L) for 180 days. The hallmarks of AD are characterized by senile plaques and neurofibrillary tangles (NFT), with associated loss of neurons, resulting in cognitive impairment and dementia. Similarly, the production of Aß and tau hyperphosphorylation was also detected in HT-22 cells treated with MC-LR. In addition, MC-LR promoted increased expressions of BACE1 and PS1, but reduced mRNA expressions of ADAM family members both in vivo and in vitro, promoting the Aß production. Moreover, we identified Akt/GSK-3ß signal pathway mediated the Aß and p-tau accumulation, bringing about Alzheimer's disease-like changes. Furthermore, microglial cells were activated in those mice exposed to MC-LR. Inflammatory cytokines were also found being activated to release in vitro. In conclusion, this study could provide a clue for MC-LR-induced neurotoxicity, which gave insights into the environmental risks of Alzheimer's disease.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Proteínas tau , Secretases da Proteína Precursora do Amiloide , Animais , Ácido Aspártico Endopeptidases , Quinase 3 da Glicogênio Sintase , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteínas tau/metabolismo
3.
Cell Rep ; 36(4): 109421, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34320342

RESUMO

Mitogen-activated protein kinases (MAPKs) are inactivated by dual-specificity phosphatases (DUSPs), the activities of which are tightly regulated during cell differentiation. Using knockdown screening and single-cell transcriptional analysis, we demonstrate that DUSP4 is the phosphatase that specifically inactivates p38 kinase to promote megakaryocyte (Mk) differentiation. Mechanistically, PRMT1-mediated methylation of DUSP4 triggers its ubiquitinylation by an E3 ligase HUWE1. Interestingly, the mechanistic axis of the DUSP4 degradation and p38 activation is also associated with a transcriptional signature of immune activation in Mk cells. In the context of thrombocytopenia observed in myelodysplastic syndrome (MDS), we demonstrate that high levels of p38 MAPK and PRMT1 are associated with low platelet counts and adverse prognosis, while pharmacological inhibition of p38 MAPK or PRMT1 stimulates megakaryopoiesis. These findings provide mechanistic insights into the role of the PRMT1-DUSP4-p38 axis on Mk differentiation and present a strategy for treatment of thrombocytopenia associated with MDS.

4.
J Hazard Mater ; 417: 126092, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015712

RESUMO

There is a growing concern regarding the toxic effects of nanoplastics (NPs) on aquatic and marine organism, while relatively few studies about their toxicity evaluation on mammals are conducted. In the present study, we observed accumulation of polystyrene NPs (PS NPs) in mice spleen, lung, kidney, small intestine, large intestine, testis, and brain after oral exposure to PS NPs (~100 nm, 10 mg/mL, 100 µL) for 28 days, and NPs were identified to induce cell apoptosis, inflammation, and structure disorder in these tissues. We also found that PS NPs could bring about hematological system injury and lipid metabolism disorder. Further in vitro studies identified that PS NPs could be absorbed by the intestinal epithelial Caco-2 cells by macropinocytosis and clathrin-mediated endocytosis, and induced disruption of tight junction between Caco-2 cells. Moreover, we found that it was easier for PS-NH2 and PS-COOH to enter into Caco-2 cells, which may be associated with observed stronger toxicity of PS-NH2 and PS-COOH NPs. In summary, this study demonstrated that NPs exposure brings about toxic effects to mice. This study could provide new insights regarding the distribution of NPs in humans, and helps us to evaluate the potential physiological risks of NPs to human beings.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Células CACO-2 , Humanos , Camundongos , Microplásticos , Nanopartículas/toxicidade , Poliestirenos/toxicidade
5.
Cell Biol Toxicol ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33474710

RESUMO

Microcystin-leucine-arginine (MC-LR) was produced by toxic cyanobacteria, which has been shown to have potent hepatotoxicity. Our previous study has proved that MC-LR were able to promote intrahepatic biliary epithelial cell excessive proliferation. However, the underlying mechanism is not yet entirely clarified. Herein, mice were fed with different concentrations (1, 7.5, 15, or 30 µg/L) of MC-LR by drinking water for 6 months. As the concentration of MC-LR increased, a growing number of macrophages were evaluated in the portal area of the mouse liver. Next, we built a co-culture system to explore the interaction between macrophages (THP-1 cells) and human intrahepatic biliary epithelial cells (HiBECs) in the presence of MC-LR. Under the exposure of MC-LR, HiBECs secreted a large amount of inflammatory factors (IL-6, IL-8, IL-1ß, COX-2, XCL-1) and chemokine (MCP-1), which produced a huge chemotactic effect on THP-1 cells and induced elevation of the surface M2-subtype biomarkers (IL-10, CD163, CCL22, and Arg-1). In turn, high content of IL-6 in the medium activated JAK2/STAT3, MEK/ERK, and PI3K/AKT pathways in HiBECs, inducing HiBEC abnormal proliferation and migration. Together, these results suggested that MC-LR-mediated interaction between HiBECs and macrophages induced the M2-type polarization of macrophages, and activated IL-6/JAK2/STAT3, MEK/ERK, and PI3K/AKT pathways in HiBECs, further enhanced cell proliferation, improved cell migration, and hindered cell apoptosis by activating p-STAT3. MC-LR stimulates HiBECs to produce various inflammatory factors, recruiting a large number of macrophages and promoting the differentiation of macrophages into M2-type. In turn, the M2 macrophages could also produce amounts of IL-6 and activate STAT3 through JAK2/STAT3, MEK/ERK, and PI3K/AKT pathways in HiBECs, resulting in the promotion of cell proliferation, inhibition of apoptosis, and enhancement of migration.

6.
Cell Mol Life Sci ; 78(3): 833-842, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32930806

RESUMO

Epsins are a family of adaptor proteins involved in clathrin-dependent endocytosis. In the vasculature, epsins 1 and 2 are functionally redundant members of this family that are expressed in the endothelial cells of blood vessels and the lymphatic system throughout development and adulthood. These proteins contain a number of peptide motifs that allow them to interact with lipid moieties and a variety of proteins. These interactions facilitate the regulation of a wide range of cell signaling pathways. In this review, we focus on the involvement of epsins 1 and 2 in controlling vascular endothelial growth factor receptor signaling in angiogenesis and lymphangiogenesis. We also discuss the therapeutic implications of understanding the molecular mechanisms of epsin-mediated regulation in diseases such as atherosclerosis and diabetes.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Aterosclerose/patologia , Neoplasias/patologia , Proteínas Adaptadoras de Transporte Vesicular/química , Aterosclerose/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Linfangiogênese , Neoplasias/metabolismo , Neovascularização Patológica , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
Chemosphere ; 264(Pt 1): 128440, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33002802

RESUMO

Microcystin-leucine-arginine (MC-LR) has been identified to be a hazardous material to cause hepatotoxicity. In this study, mice were exposed to MC-LR dissolved in drinking water at doses of 1, 10, 20 and 30 µg/L for 90 and 180 days, respectively. We validated MC-LR accelerated spermatid exfoliation and caused large vacuoles in testes, reducing sperm count and increasing percentage of morphologically abnormal sperm. Furthermore, we found MC-LR induced the apical ectoplasmic specialization (ES) disassembly by disrupting F-actin organization. Further studies identified that downregulation of Palladin, the actin crosslinking protein, might be associated with disassembly of the apical ES in mice testis following MC-LR exposure. We also confirmed that MC-LR disrupted the interaction between Palladin and other actin-related proteins and thus impeded the F-actin organization. Additionally, we found that autophagy initiated by AMPK/ULK1 signaling pathway mediated the degradation of Palladin in Sertoli cells challenged with MC-LR. Following exposure to MC-LR, reduced PP2A activity and upregulated expression of LKB1 and CAMKK2 could activate AMPK. In conclusion, these results revealed MC-LR induced the degradation of Palladin via AMPK/ULK1-mediated autophagy, which might result in the apical ES disorder and spermatid exfoliation from spermatogenic epithelium. Our work may provide a new perspective to understand MC-LR-induced male infertility.


Assuntos
Arginina , Microcistinas , Animais , Leucina , Masculino , Camundongos , Microcistinas/toxicidade , Células de Sertoli , Testículo
8.
Autophagy ; 17(2): 457-475, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31983283

RESUMO

Macroautophagy/autophagy is indispensable for testosterone synthesis in Leydig cells (LCs), and here we report a negative association between m6A modification and autophagy in LCs during testosterone synthesis. A gradual decrease of METTL14 (methyltransferase like 14) and an increase of ALKBH5 (alkB homolog 5, RNA demethylase) were observed in LCs during their differentiation from stem LCs to adult LCs. These events led to reduced mRNA methylation levels of N6-methyladenosine (m6A) and enhanced autophagy in LCs. Similar regulation of METTL14, ALKBH5, and m6A was also observed in LCs upon treatment with human chorionic gonadotropin (HsCG). Mechanistically, m6A modification promoted translation of PPM1A (protein phosphatase 1A, magnesium dependent, alpha isoform), a negative AMP-activated protein kinase (AMPK) regulator, but decreased expression of CAMKK2 (calcium/calmodulin-dependent protein kinase kinase 2, beta), a positive AMPK regulator, by reducing its RNA stability. Thus, m6A modification resulted in reduced AMPK activity and subsequent autophagy inhibition. We further demonstrated that ALKBH5 upregulation by HsCG was dependent on enhanced binding of the transcriptional factor CEBPB (CCAAT/enhancer binding protein [C/EBP], beta) and the TFEB (transcription factor EB) to its gene promoter. Moreover, HsCG treatment decreased METTL14 by reducing its stability. Collectively, this study highlights a vital role of m6A RNA methylation in the modulation of testosterone synthesis in LCs, providing insight into novel therapeutic strategies by exploiting m6A RNA methylation as targets for treating azoospermatism and oligospermatism patients with reduction in serum testosterone.Abbreviations: 3-MA: 3-methyladenine; ACTB: Actin, beta; ALKBH5: alkB homolog 5, RNA demethylase; AMPK: AMP-activated protein kinase; BafA1: bafilomycin A1; CAMKK2: calcium/calmodulin-dependent protein kinase kinase 2, beta; CEBPB: CCAAT/enhancer-binding protein (C/EBP), beta; ChIP: chromatin immunoprecipitation; FTO: fat mass and obesity associated; HsCG: human chorionic gonadotropin; HSD3B: 3ß-hydroxysteroid dehydrogenase; LCs: Leydig cells; m6A: N6-methyladenosine; METTL14: methyltransferase like 14; METTL3: methyltransferase like 3; MTOR: mechanistic target of rapamycin kinase; PPM1A: protein phosphatase 1A, magnesium dependent, alpha isoform; PRKAA: 5'-AMP-activated protein kinase catalytic subunit alpha; SQSTM1: sequestosome 1; STK11/LKB1: serine/threonine kinase 11; TFEB: transcription factor EB; ULK1: unc-51-like kinase 1; WTAP: Wilms tumor 1-associating protein; YTHDF: YTH N6-methyladenosine RNA binding protein.

9.
Arterioscler Thromb Vasc Biol ; 41(1): 20-34, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33115268

RESUMO

Despite successful therapeutic strategies in the prevention and treatment of arteriosclerosis, the cardiovascular complications remain a major clinical and societal issue worldwide. Increased vascular calcification promotes arterial stiffness and accelerates cardiovascular morbidity and mortality. Upregulation of the Runx2 (Runt-related transcription factor 2), an essential osteogenic transcription factor for bone formation, in the cardiovascular system has emerged as an important regulator for adverse cellular events that drive cardiovascular pathology. This review discusses the regulatory mechanisms that are critical for Runx2 expression and function and highlights the dynamic and complex cross talks of a wide variety of posttranslational modifications, including phosphorylation, acetylation, ubiquitination, and O-linked ß-N-acetylglucosamine modification, in regulating Runx2 stability, cellular localization, and osteogenic transcriptional activity. How the activation of an array of signaling cascades by circulating and local microenvironmental factors upregulates Runx2 in vascular cells and promotes Runx2-mediated osteogenic transdifferentiation of vascular smooth muscle cells and expression of inflammatory cytokines that accelerate macrophage infiltration and vascular osteoclast formation is summarized. Furthermore, the increasing appreciation of a new role of Runx2 upregulation in promoting vascular smooth muscle cell phenotypic switch, and Runx2 modulated by O-linked ß-N-acetylglucosamine modification and Runx2-dependent repression of smooth muscle cell-specific gene expression are discussed. Further exploring the regulation of this key osteogenic transcription factor and its new perspectives in the vasculature will provide novel insights into the transcriptional regulation of vascular smooth muscle cell phenotype switch, reprograming, and vascular inflammation that promote the pathogenesis of arteriosclerosis.


Assuntos
Artérias/metabolismo , Arteriosclerose/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Transcrição Genética , Calcificação Vascular/metabolismo , Animais , Artérias/patologia , Arteriosclerose/genética , Arteriosclerose/patologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Humanos , Osteogênese , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Calcificação Vascular/genética , Calcificação Vascular/patologia , Remodelação Vascular
10.
J Hazard Mater ; 401: 123430, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32659591

RESUMO

Microplastics (MPs) have become hazardous materials, which have aroused widespread concern about their potential toxicity. However, the effects of MPs on reproductive systems in mammals are still ambiguous. In this study, the toxic effects of polystyrene MPs (PS-MPs) in male reproduction of mice were investigated. The results indicated that after exposure for 24 h, 4 µm and 10 µm PS-MPs accumulated in the testis of mice. Meanwhile, 0.5 µm, 4 µm, and 10 µm PS-MPs could enter into three kinds of testicular cells in vitro. In addition, sperm quality and testosterone level of mice were declined after exposure to 0.5 µm, 4 µm, and 10 µm PS-MPs for 28 days. H&E staining showed that spermatogenic cells abscissed and arranged disorderly, and multinucleated gonocytes occurred in the seminiferous tubule. Moreover, PS-MPs induced testicular inflammation and the disruption of blood-testis barrier. In summary, this study demonstrated that PS-MPs induced male reproductive dysfunctions in mice, which provided new insights into the toxicity of MPs in mammals.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Masculino , Camundongos , Plásticos , Poliestirenos/toxicidade , Reprodução , Espermatozoides , Poluentes Químicos da Água/toxicidade
12.
Medicine (Baltimore) ; 99(29): e21166, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32702872

RESUMO

INTRODUCTION: Insomnia is a major public health problem. Due to the side effects of pharmacological therapy, people are seeking to choose complementary and alternative therapies for insomnia disorder. Traditional Chinese herbal bath therapy is an important complementary therapy which combines advantages of Chinese herbs and bathing therapy. This protocol describes the methodology of a systematic review assessing the effectiveness and safety of traditional Chinese herbal bath therapy for insomnia. METHODS AND ANALYSIS: Reporting of this review will be adherent to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We will electronically search the following seven databases from inception to January 23, 2020: PubMed, Cochrane database (CENTRAL), EMBASE, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), VIP Database, and Wanfang Database. Parallel randomized controlled trials evaluating the effectiveness and safety of traditional Chinese herbal bath therapy for insomnia will be included. Study selection, data extraction and assessment of risk of bias will be performed independently by two researchers. The sleep quality will be assessed as the primary outcome. Global symptom improvement, anxiety and depression, and adverse events will be evaluated as secondary outcomes. The Cochrane's risk of bias tool will be utilized for assessing the methodological quality of included studies. Revman software (v.5.3) will be used for data synthesis and statistical analysis. Data will be synthesized by either fixed-effects or random-effects model according to a heterogeneity test. If it is not appropriate for a meta-analysis, a descriptive analysis will be conducted. GRADE system will be used to assess the quality of evidence. PROSPERO REGISTRATION NUMBER: CRD42020168507.


Assuntos
Banhos/normas , Protocolos Clínicos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Banhos/métodos , Medicina Herbária/métodos , Medicina Herbária/normas , Humanos , Medicina Tradicional Chinesa/métodos , Medicina Tradicional Chinesa/normas , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Revisões Sistemáticas como Assunto
13.
Arterioscler Thromb Vasc Biol ; 40(5): 1078-1093, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32237904

RESUMO

This review focuses on the association between vascular calcification and arterial stiffness, highlighting the important genetic factors, systemic and local microenvironmental signals, and underlying signaling pathways and molecular regulators of vascular calcification. Elevated oxidative stress appears to be a common procalcification factor that induces osteogenic differentiation and calcification of vascular cells in a variety of disease conditions such as atherosclerosis, diabetes mellitus, and chronic kidney disease. Thus, the role of oxidative stress and oxidative stress-regulated signals in vascular smooth muscle cells and their contributions to vascular calcification are highlighted. In relation to diabetes mellitus, the regulation of both hyperglycemia and increased protein glycosylation, by AGEs (advanced glycation end products) and O-linked ß-N-acetylglucosamine modification, and its role in enhancing intracellular pathophysiological signaling that promotes osteogenic differentiation and calcification of vascular smooth muscle cells are discussed. In the context of chronic kidney disease, this review details the role of calcium and phosphate homeostasis, parathyroid hormone, and specific calcification inhibitors in regulating vascular calcification. In addition, the impact of the systemic and microenvironmental factors on respective intrinsic signaling pathways that promote osteogenic differentiation and calcification of vascular smooth muscle cells and osteoblasts are compared and contrasted, aiming to dissect the commonalities and distinctions that underlie the paradoxical vascular-bone mineralization disorders in aging and diseases.


Assuntos
Artérias/fisiopatologia , Osteogênese , Calcificação Vascular/fisiopatologia , Remodelação Vascular , Rigidez Vascular , Fatores Etários , Animais , Artérias/metabolismo , Artérias/patologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Diabetes Mellitus/fisiopatologia , Predisposição Genética para Doença , Humanos , Nefropatias/epidemiologia , Nefropatias/patologia , Nefropatias/fisiopatologia , Estresse Oxidativo , Fatores de Risco , Transdução de Sinais , Calcificação Vascular/epidemiologia , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia
14.
Arterioscler Thromb Vasc Biol ; 40(5): 1352-1369, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32212850

RESUMO

OBJECTIVE: Abdominal aortic aneurysms (AAAs) are highly lethal diseases without effective clinical predictors and therapeutic targets. Vascular microcalcification, as detected by fluorine-18-sodium fluoride, has recently been recognized as a valuable indicator in predicting atherosclerotic plaque rupture and AAA expansion. However, whether vascular microcalcification involved in the pathogenesis of AAA remains elusive. Approach and Results: Microcalcification was analyzed in human aneurysmal aortas histologically and in AngII (angiotensin II)-infused ApoE-/- mouse aortas by fluorine-18-sodium fluoride positron emission tomography and X-ray computed tomography scanning in chronological order in live animals. AAA patients' aortic tissue showed markedly enhanced microcalcification in the aortic media within the area proximal to elastic fiber degradation, compared with non-AAA patients. Enhanced fluorine-18-sodium fluoride uptake preceded significant aortic expansion in mice. Microcalcification-positive mice on day 7 of AngII infusion showed dramatic aortic expansion on subsequent days 14 to 28, whereas microcalcification-negative AngII-infused mice and saline-induced mice did not develop AAA. The application of hydroxyapatite, the main component of microcalcification, aggravated AngII-induced AAA formation in vivo. RNA-sequencing analysis of the suprarenal aortas of 4-day-AngII-infused ApoE-/- mice and bioinformatics analysis with ChIP-Atlas database identified the potential involvement of the osteogenic transcriptional factor Runx2 (runt-related transcription factor 2) in AAA. Consistently, vascular smooth muscle cell-specific Runx2 deficiency markedly repressed AngII-induced AAA formation in the ApoE-/- mice compared with the control littermates. CONCLUSIONS: Our studies have revealed microcalcification as a novel pathological characteristic and potential mediator of AAA, and targeting microcalcification may represent a promising strategy for AAA prevention and treatment.


Assuntos
Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Calcificação Vascular/metabolismo , Adulto , Angiotensina II , Animais , Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/genética , Estudos de Casos e Controles , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Dilatação Patológica , Modelos Animais de Doenças , Durapatita , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Transdução de Sinais , Calcificação Vascular/induzido quimicamente , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/genética , Remodelação Vascular
15.
Lab Invest ; 100(5): 777-785, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31896813

RESUMO

TRAIL-activating therapy is promising in treating various cancers, including pancreatic cancer, a highly malignant neoplasm with poor prognosis. However, many pancreatic cancer cells are resistant to TRAIL-induced apoptosis despite their expression of intact death receptors (DRs). Protein O-GlcNAcylation is a versatile posttranslational modification that regulates various biological processes. Elevated protein O-GlcNAcylation has been recently linked to cancer cell growth and survival. In this study, we evaluated the role of protein O-GlcNAcylation in pancreatic cancer TRAIL resistance, and identified higher levels of O-GlcNAcylation in TRAIL-resistant pancreatic cancer cells. With gain- and loss-of-function of the O-GlcNAc-adding enzyme, O-GlcNActransferase (OGT), we determined that increasing O-GlcNAcylation rendered TRAIL-sensitive cells more resistant to TRA-8-induced apoptosis, while inhibiting O-GlcNAcylation promoted TRA-8-induced apoptosis in TRAIL-resistance cells. Furthermore, we demonstrated that OGT knockdown sensitized TRAIL-resistant cells to TRA-8 therapy in a mouse model in vivo. Mechanistic studies revealed direct O-GlcNAc modifications of DR5, which regulated TRA-8-induced DR5 oligomerization. We further defined that DR5 O-GlcNAcylation was independent of FADD, the adapter protein for the downstream death-inducing signaling. These studies have demonstrated an important role of protein O-GlcNAcylation in regulating TRAIL resistance of pancreatic cancer cells; and uncovered the contribution of O-GlcNAcylation to DR5 oligomerization and thus mediating DR-inducing signaling.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , N-Acetilglucosaminiltransferases , Neoplasias Pancreáticas , Ligante Indutor de Apoptose Relacionado a TNF , Acetilglucosamina/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
16.
Sci Total Environ ; 703: 134702, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31753492

RESUMO

Microcystin-leucine-arginine (MC-LR) can cross the blood-brain barrier (BBB) and demonstrate potent acute hippocampal neurotoxicity. Chronic exposure to MC-LR has been confirmed to cause learning and memory deficits in mice, but the potential molecular mechanism of MC-LR-caused neurotoxicity is still unclear. In this research, we observed that MC-LR induced oxidative stress, mitochondrial fission and apoptosis in HT-22 hippocampal neurons. Moreover, further studies identified that MC-LR induced mitochondrial fragmentation via activating Dynamin-related protein 1 (Drp1) and Mitochondrial fission factor (Mff), contributing to apoptosis of hippocampal neuronal cells. The observed effects were associated with increased intracellular Ca2+ and reduced activity of protein phosphatases 2A (PP2A) as results of MC-LR exposure in hippocampal neuron cells. Ca2+ activates CaMK II and Akt to enhance phosphorylation of Drp1 at Ser616 residue. Inhibition of PP2A activity increased AMPK activity to mediate phosphorylation of Mff. Our data proved that MC-LR can cause mitochondrial fragmentation in hippocampal neurons, which provides novel perception to explore the underlying molecular mechanism associated with MC-LR-induced neurotoxicity and Alzheimer's disease-like changes.


Assuntos
Hipocampo , Animais , Apoptose , Arginina , Linhagem Celular , Leucina , Camundongos , Microcistinas , Dinâmica Mitocondrial , Neurônios
17.
Arterioscler Thromb Vasc Biol ; 39(10): 1911-1924, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31462094

RESUMO

Mammalian cells metabolize glucose primarily for energy production, biomass synthesis, and posttranslational glycosylation; and maintaining glucose metabolic homeostasis is essential for normal physiology of cells. Impaired glucose homeostasis leads to hyperglycemia, a hallmark of diabetes mellitus. Chronically increased glucose in diabetes mellitus promotes pathological changes accompanied by impaired cellular function and tissue damage, which facilitates the development of cardiovascular complications, the major cause of morbidity and mortality of patients with diabetes mellitus. Emerging roles of glucose metabolism via the hexosamine biosynthesis pathway (HBP) and increased protein modification via O-linked ß-N-acetylglucosamine (O-GlcNAcylation) have been demonstrated in diabetes mellitus and implicated in the development of diabetic cardiovascular complications. This review will discuss the biological outcomes of the glucose metabolism via the hexosamine biogenesis pathway and protein O-GlcNAcylation in regulating cellular homeostasis, and highlight the regulations and contributions of elevated O-GlcNAcylation to the pathogenesis of diabetic cardiovascular disease.


Assuntos
Acetilglucosamina/metabolismo , Diabetes Mellitus/metabolismo , Cardiomiopatias Diabéticas/metabolismo , N-Acetilglucosaminiltransferases/genética , Estresse Fisiológico/genética , Animais , Cardiomiopatias Diabéticas/fisiopatologia , Humanos , Camundongos , Prognóstico , Processamento de Proteína Pós-Traducional/genética , Papel (figurativo) , Transdução de Sinais/genética
18.
Sci Total Environ ; 689: 662-678, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279213

RESUMO

Microcystin-leucine-arginine (MC-LR), which produced by toxic cyanobacteria and widely present in eutrophic waters, has been shown to have potent acute hepatotoxicity. MC-LR has been revealed to inflict damage to brain, while the neurotoxicity of chronic exposure to MC-LR and mechanisms underlying it are still confusing. Here, the mice were exposed to MC-LR dissolved in drinking water at dose of 1, 7.5, 15, and 30 µg/L for consecutive 180 days. MC-LR accumulated in mouse brains and impaired the blood-brain barrier by inducing the expression of matrix metalloproteinase-8 (MMP-8), which was regulated by NF-κB, c-Fos and c-Jun. Furthermore, MC-LR exposure induced microglial and astrocyte activation and resultant neuroinflammatory response. This study highlights the risks to human health of the current microcystin exposure.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Inflamação/fisiopatologia , Microcistinas/toxicidade , Junções Íntimas/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Masculino , Toxinas Marinhas , Camundongos , Camundongos Endogâmicos BALB C , Microglia/efeitos dos fármacos , Microglia/fisiologia , Junções Íntimas/metabolismo
19.
Stem Cells Int ; 2019: 6183796, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281378

RESUMO

During the development of endometriosis, the presence of fibrotic tissues in and surrounding endometriotic lesions may lead to subsequent adhesion, anatomic distortion, and chronic pain. Therefore, studies aimed at clarifying the underlying mechanisms of fibrogenesis in endometriosis could potentially provide a novel strategy for effective treatment. Mesenchymal stem cells (MSCs) play a key role in fibrotic diseases by differentiating into myofibroblasts in appropriate microenvironment. In this study, we collected endometrial and endometriotic tissues from patients with endometriosis (n = 32) and control patients without endometriosis (n = 20) to compare the expression of fibrotic proteins and investigate the effect of endometriotic peritoneal fluid (PF) on myofibroblast differentiation of endometrial MSCs. We found that the expression of fibrotic proteins, including alpha-smooth muscle actin (α-SMA), type I collagen (collagen I), connective tissue growth factor (CTGF), and fibronectin, and the extent of fibrosis extremely enhanced in ectopic endometria compared with eutopic endometria from the same patients with endometriosis and normal endometria from patients without endometriosis. We next isolated and identified endometrial MSCs and found that treatment with endometriotic PF strongly induced endometrial MSCs to differentiate into myofibroblasts concomitant with the activation of Smad2/3. Moreover, ectopic endometrial MSCs expressed elevated collagen I, α-SMA, fibronectin, and CTGF. Sushi domain containing-2 (SUSD2), a marker of endometrial MSCs, and α-SMA, a well-recognized marker for myofibroblasts, colocalized extensively in ectopic endometria while seldom in normal and eutopic endometria. These findings suggest that ectopic endometrial MSCs are probably more susceptible to myofibroblast differentiation because of the long-term influence of endometriotic PF. All together, we report for the first time that endometriotic PF promotes myofibroblast differentiation of endometrial MSCs. This understanding will greatly improve our understanding of the pathophysiology of endometriosis and help design better therapeutics.

20.
Cell Commun Signal ; 17(1): 45, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101053

RESUMO

BACKGROUND: Endometriosis, characterized by the presence of functional endometrial tissues outside the uterus, is one of the most common gynecological disorders. Endometrial mesenchymal stem cells (MSCs) are crucial for the occurrence and development of endometriosis. Ectopic endometrial MSCs exist in the peritoneal cavity. Thus, the bioactive factors in endometriotic peritoneal fluid may regulate the biological behaviors of endometrial MSCs. METHODS: In this study, after assessing the concentration of Activin A in peritoneal fluid using ELISA, we isolated and cultured endometrial MSCs and investigated whether Activin A stimulated endometrial MSCs to differentiate into myofibroblasts and clarified the underlying mechanisms by quantitative real-time PCR, Western blot analysis, immunofluorescent staining, RNA interference and Chromatin immunoprecipitation. We also employed the inhibitors of Activin A to explore the possibility of suppressing the development of fibrosis in endometriosis using primary endometrial MSCs cultures and a mouse model of endometriosis. RESULTS: Here, we revealed that Activin A significantly elevated in endometriotic peritoneal fluid and activin receptor-like kinase (ALK4), the specific receptor for Activin A, obviously enhanced in ectopic endometrial MSCs compared with eutopic endometrial MSCs from women with or without endometriosis. Next, we found that Activin A drived myofibroblast differentiation of endometrial MSCs, with extremely enhanced expression of connective tissue growth factor (CTGF). CTGF was shown to be required for Activin A-induced expression of ACTA2, COL1A1 and FN1 in endometrial MSCs. CTGF induction by Activin A in endometrial MSCs involved the activation of Smad2/3, as evidenced by the phosphorylation and nuclear translocation of Smad2/3 as well as the binding of Smad2/3 to CTGF promoter. Furthermore, Smad/CTGF pathway in endometrial MSCs required activation of STAT3 while independent of PI3K, JNK and p-38 pathways. In addition, we also demonstrated that inhibition of Activin A pathway impeded myofibroblast differentiation of endometrial MSCs and ameliorated fibrosis in endometriosis mice. CONCLUSIONS: Activin A promotes myofibroblast differentiation of endometrial mesenchymal stem cells via STAT3-dependent Smad/CTGF pathway. The results provided the first evidence that STAT3 acted as a crucial Activin A downstream mediator to regulate CTGF production. Our data may supplement the stem cell theory of endometriosis and provide the experimental basis to treat endometriosis-associated fibrosis by manipulating Activin A signaling.


Assuntos
Ativinas/metabolismo , Diferenciação Celular , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Endometriose/metabolismo , Miofibroblastos/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteínas Smad/metabolismo , Actinas/genética , Actinas/metabolismo , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo , Ativinas/genética , Adulto , Animais , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Óxidos S-Cíclicos/uso terapêutico , Endometriose/tratamento farmacológico , Endométrio/metabolismo , Feminino , Fibronectinas/genética , Fibronectinas/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Miofibroblastos/citologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...