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1.
Am J Pathol ; 193(12): 2182-2202, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37673329

RESUMO

Liver is the largest lymph-producing organ. In cirrhotic patients, lymph production significantly increases concomitant with lymphangiogenesis. The aim of this study was to determine the mechanism of lymphangiogenesis in liver and its implication in liver fibrosis. Liver biopsies from portal hypertensive patients with portal-sinusoidal vascular disease (n = 22) and liver cirrhosis (n = 5) were evaluated for lymphangiogenesis and compared with controls (n = 9 and n = 6, respectively). For mechanistic studies, rats with partial portal vein ligation (PPVL) and bile duct ligation (BDL) were used. A gene profile data set (GSE77627), including 14 histologically normal liver, 18 idiopathic noncirrhotic portal hypertension, and 22 cirrhotic patients, was analyzed. Lymphangiogenesis was significantly increased in livers from patients with portal-sinusoidal vascular disease, cirrhotic patients, as well as PPVL and BDL rats. Importantly, Schwann cells of sympathetic nerves highly expressed vascular endothelial growth factor-C in PPVL rats. Vascular endothelial growth factor-C neutralizing antibody or sympathetic denervation significantly decreased lymphangiogenesis in livers of PPVL and BDL rats, which resulted in progression of liver fibrosis. Liver specimens from cirrhotic patients showed a positive correlation between sympathetic nerve/Schwann cell-positive areas and lymphatic vessel numbers, which was supported by gene set analysis from patients with noncirrhotic portal hypertension and cirrhotic patients. Sympathetic nerves promote hepatic lymphangiogenesis in noncirrhotic and cirrhotic livers. Increased hepatic lymphangiogenesis can be protective against liver fibrosis.


Assuntos
Doenças Vasculares , Fator C de Crescimento do Endotélio Vascular , Ratos , Humanos , Animais , Linfangiogênese , Ratos Sprague-Dawley , Modelos Animais de Doenças , Cirrose Hepática/patologia , Fígado/patologia , Doenças Vasculares/patologia , Sistema Nervoso Simpático
2.
Am J Physiol Gastrointest Liver Physiol ; 325(5): G379-G390, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37605828

RESUMO

The liver lymphatic system is essential for maintaining tissue fluid balance and immune function. The detailed structure of lymphatic vessels (LVs) in the liver remains to be fully demonstrated. The aim of this study is to reveal LV structures in normal and diseased livers by developing a tissue-clearing and coimmunolabeling protocol optimized for the tissue size and the processing time for three-dimensional (3-D) visualization and quantification of LVs in the liver. We showed that our optimized protocol enables in-depth exploration of lymphatic networks in the liver, consisting of LVs along the portal tract (deep lymphatic system) and within the collagenous Glisson's capsule (superficial lymphatic system) in different species. With this protocol, we have shown 3-D LVs configurations in relation to blood vessels and bile ducts in cholestatic mouse livers, in which LVs were highly dilated and predominantly found around highly proliferating bile ducts and peribiliary vascular plexuses in the portal tract. We also established a quantification method using a 3-D volume-rendering approach. We observed a 1.6-fold (P < 0.05) increase in the average diameter of LVs and a 2.4-fold increase (P < 0.05) in the average branch number of LVs in cholestatic/fibrotic livers compared with control livers. Furthermore, cholestatic/fibrotic livers showed a 4.3-fold increase (P < 0.05) in total volume of LVs compared with control livers. Our optimized protocol and quantification method demonstrate an efficient and simple liver tissue-clearing procedure that allows the comprehensive analysis of liver lymphatic system.NEW & NOTEWORTHY This article showed a comprehensive 3-D-structural analysis of liver lymphatic vessel (LV) in normal and diseased livers in relation to blood vessels and bile ducts. In addition to the LVs highly localized at the portal tract, we revealed capsular LVs in mouse, rat, and human livers. In cholestatic livers, LVs are significantly increased and dilated compared with normal livers. Our optimized protocol provides detailed spatial information for LVs remodeling in normal and pathological conditions.


Assuntos
Colestase , Vasos Linfáticos , Ratos , Humanos , Camundongos , Animais , Fígado/patologia , Ductos Biliares , Vasos Linfáticos/diagnóstico por imagem , Vasos Linfáticos/patologia , Colestase/patologia , Cirrose Hepática/patologia
3.
J Hepatol ; 77(1): 206-218, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35157960

RESUMO

In recent years, significant advances have been made in the study of lymphatic vessels with the identification of their specific markers and the development of research tools that have accelerated our understanding of their role in tissue homeostasis and disease pathogenesis in many organs. Compared to other organs, the lymphatic system in the liver is understudied despite its obvious importance for hepatic physiology and pathophysiology. In this review, we describe fundamental aspects of the hepatic lymphatic system and its role in a range of liver-related pathological conditions such as portal hypertension, ascites formation, malignant tumours, liver transplantation, congenital liver diseases, non-alcoholic fatty liver disease, and hepatic encephalopathy. The article concludes with a discussion regarding the modulation of lymphangiogenesis as a potential therapeutic strategy for liver diseases.


Assuntos
Hipertensão Portal , Vasos Linfáticos , Humanos , Linfangiogênese , Sistema Linfático
4.
Gastroenterology ; 160(4): 1315-1329.e13, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33227282

RESUMO

BACKGROUND & AIMS: Hepatic encephalopathy (HE) is a serious neurologic complication in patients with liver cirrhosis. Very little is known about the role of the meningeal lymphatic system in HE. We tested our hypothesis that enhancement of meningeal lymphatic drainage could decrease neuroinflammation and ameliorate HE. METHODS: A 4-week bile duct ligation model was used to develop cirrhosis with HE in rats. Brain inflammation in patients with HE was evaluated by using archived GSE41919. The motor function of rats was assessed by the rotarod test. Adeno-associated virus 8-vascular endothelial growth factor C (AAV8-VEGF-C) was injected into the cisterna magna of HE rats 1 day after surgery to induce meningeal lymphangiogenesis. RESULTS: Cirrhotic rats with HE showed significantly increased microglia activation in the middle region of the cortex (P < .001) as well as increased neuroinflammation, as indicated by significant increases in interleukin 1ß, interferon γ, tumor necrosis factor α, and ionized calcium binding adaptor molecule 1 (Iba1) expression levels in at least 1 of the 3 regions of the cortex. Motor function was also impaired in rats with HE (P < .05). Human brains of patients with cirrhosis with HE also exhibited up-regulation of proinflammatory genes (NFKB1, IbA1, TNF-α, and IL1ß) (n = 6). AAV8-VEGF-C injection significantly increased meningeal lymphangiogenesis (P = .035) and tracer dye uptake in the anterior and middle regions of the cortex (P = .006 and .003, respectively), their corresponding meninges (P = .086 and .006, respectively), and the draining lymph nodes (P = .02). Furthermore, AAV8-VEGF-C decreased microglia activation (P < .001) and neuroinflammation and ameliorated motor dysfunction (P = .024). CONCLUSIONS: Promoting meningeal lymphatic drainage and enhancing waste clearance improves HE. Manipulation of meningeal lymphangiogenesis could be a new therapeutic strategy for the treatment of HE.


Assuntos
Sistema Glinfático/patologia , Encefalopatia Hepática/imunologia , Cirrose Hepática/complicações , Transtornos Motores/imunologia , Fator C de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular , Córtex Cerebral/imunologia , Córtex Cerebral/patologia , Cisterna Magna/imunologia , Cisterna Magna/patologia , Dependovirus/genética , Modelos Animais de Doenças , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Sistema Glinfático/imunologia , Encefalopatia Hepática/patologia , Humanos , Cirrose Hepática/imunologia , Linfangiogênese/imunologia , Masculino , Microglia/imunologia , Microglia/patologia , Transtornos Motores/patologia , Ratos , Fator C de Crescimento do Endotélio Vascular/genética
5.
J Hepatol ; 75(2): 377-386, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33675874

RESUMO

BACKGROUND & AIMS: Liver sinusoidal endothelial cell (LSEC) dysfunction has been reported in alcohol-related liver disease, yet it is not known whether LSECs metabolize alcohol. Thus, we investigated this, as well as the mechanisms of alcohol-induced LSEC dysfunction and a potential therapeutic approach for alcohol-induced liver injury. METHODS: Primary human, rat and mouse LSECs were used. Histone deacetylase 6 (HDAC6) was overexpressed specifically in liver ECs via adeno-associated virus (AAV)-mediated gene delivery to decrease heat shock protein 90 (Hsp90) acetylation in ethanol-fed mice. RESULTS: LSECs expressed CYP2E1 and alcohol dehydrogenase 1 (ADH1) and metabolized alcohol. Ethanol induced CYP2E1 in LSECs, but not ADH1. Alcohol metabolism by CYP2E1 increased Hsp90 acetylation and decreased its interaction with endothelial nitric oxide synthase (eNOS) leading to a decrease in nitric oxide (NO) production. A non-acetylation mutant of Hsp90 increased its interaction with eNOS and NO production, whereas a hyperacetylation mutant decreased NO production. These results indicate that Hsp90 acetylation is responsible for decreases in its interaction with eNOS and eNOS-derived NO production. AAV8-driven HDAC6 overexpression specifically in liver ECs deacetylated Hsp90, restored Hsp90's interaction with eNOS and ameliorated alcohol-induced liver injury in mice. CONCLUSION: Restoring LSEC function is important for ameliorating alcohol-induced liver injury. To this end, blocking acetylation of Hsp90 specifically in LSECs via AAV-mediated gene delivery has the potential to be a new therapeutic strategy. LAY SUMMARY: Alcohol metabolism in liver sinusoidal endothelial cells (LSECs) and the mechanism of alcohol-induced LSEC dysfunction are largely unknown. Herein, we demonstrate that LSECs can metabolize alcohol. We also uncover a mechanism by which alcohol induces LSEC dysfunction and liver injury, and we identify a potential therapeutic strategy to prevent this.


Assuntos
Acetilação/efeitos dos fármacos , Hepatopatias Alcoólicas/genética , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/fisiopatologia , Análise de Variância , Animais , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Proteínas de Choque Térmico HSP90 , Humanos , Hepatopatias Alcoólicas/etiologia , Camundongos , Ratos
6.
Scand J Immunol ; 89(6): e12764, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30892738

RESUMO

Serum amyloid A (SAA) is an acute phase protein with pro-inflammatory cytokine-like properties. Recent studies have revealed that SAA promoted interleukin-17 (IL-17) production by various cells, including γδ T cells. γδ T cells are innate immune cells and express Toll-like receptor 2 (TLR2) on their surface, which is one of the SAA receptors. In this study, we investigated the relationship between γδ T cells and SAA1 through TLR2, by using hepatic SAA1-overexpressing transgenic (TG) mice. By injecting CU-CPT22, which is a TLR2 inhibitor, into the mice, we confirmed that SAA1 induced IL-17 in γδ T cells through TLR2. In vitro studies have confirmed that SAA1 increased IL-17 secretion in γδ T cells in combination with IL-23. We also observed a thickened epidermis layer and granulocyte penetration into the skin similar to the pathology of psoriasis in TG mice. In addition, strongly expressed SAA1 and penetration of γδ T cells in the skin of TG mice were detected. The exacerbation of psoriasis is associated with an increase in IL-17 levels. Therefore, these symptoms were induced by IL-17-producing γδ T cells increased by SAA1. Our study confirmed that SAA1 was a prominent protein that increased IL-17 levels through TLR2 in γδ T cells, confirming the possibility that SAA1 may exacerbate inflammatory diseases through γδ T cells.


Assuntos
Interleucina-17/biossíntese , Psoríase/patologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Proteína Amiloide A Sérica/imunologia , Receptor 2 Toll-Like/imunologia , Animais , Células Cultivadas , Subunidade p19 da Interleucina-23/biossíntese , Subunidade p19 da Interleucina-23/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Psoríase/imunologia , RNA Mensageiro/biossíntese , Receptor 2 Toll-Like/antagonistas & inibidores
7.
FASEB J ; 32(1): 390-403, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28899881

RESUMO

Ten-eleven translocation methylcytosine dioxygenase 1 (Tet1) initiates DNA demethylation by converting 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) at CpG-rich regions of genes, which have key roles in adult neurogenesis and memory. In addition, the overexpression of Tet1 with 5-hmC alteration in patients with psychosis has also been reported, for instance in schizophrenia and bipolar disorders. The mechanism underlying Tet1 overexpression in the brain; however, is still elusive. In the present study, we found that Tet1-transgenic (Tet1-TG) mice displayed abnormal behaviors involving elevated anxiety and enhanced fear memories. We confirmed that Tet1 overexpression affected adult neurogenesis with oligodendrocyte differentiation in the hippocampal dentate gyrus of Tet1-TG mice. In addition, Tet1 overexpression induced the elevated expression of immediate early genes, such as Egr1, c-fos, Arc, and Bdnf, followed by the activation of intracellular calcium signals (i.e., CamKII, ERK, and CREB) in prefrontal and hippocampal neurons. The expression of GABA receptor subunits (Gabra2 and Gabra4) fluctuated in the prefrontal cortex and hippocampus. We evaluated the effects of Tet1 overexpression on intracellular calcium-dependent cascades by activating the Egr1 promoter in vitro Tet1 enhanced Egr1 expression, which may have led to alterations in Gabra2 and Gabra4 expression in neurons. Taken together, we suggest that the Tet1 overexpression in our Tet1-TG mice can be applied as an effective model for studying various stress-related diseases that show hyperactivation of intracellular calcium-dependent cascades in the brain.-Kwon, W., Kim, H.-S., Jeong, J., Sung, Y., Choi, M., Park, S., Lee, J., Jang, S., Kim, S. H., Lee, S., Kim, M. O., Ryoo, Z. Y. Tet1 overexpression leads to anxiety-like behavior and enhanced fear memories via the activation of calcium-dependent cascade through Egr1 expression in mice.


Assuntos
Ansiedade/genética , Ansiedade/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Medo/fisiologia , Memória/fisiologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Animais , Sinalização do Cálcio , Proteínas de Ligação a DNA/antagonistas & inibidores , Epigênese Genética , Feminino , Técnicas de Silenciamento de Genes , Genes Precoces , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese/genética , Neurônios/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Córtex Pré-Frontal/metabolismo , Gravidez , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores de GABA-A/genética , Regulação para Cima
8.
Mol Cell Probes ; 47: 101440, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31445970

RESUMO

Pre-mRNA processing factor 4 (PRPF4), a core protein in U4/U6 snRNP, maintains snRNP structures by interacting with PRPF3 and cyclophilin H. Expression of the PRPF4 gene affects cell survival as well as apoptosis and is responsible for retinitis pigmentosa (RP). Proteomics analysis shows that PRPF4 may be a therapeutic target in human cancers. Nevertheless, the exact function and role of the PRPF4 gene are unclear. In this study, we assessed the expression of PRPF4 gene in human breast cancer cells. First, we confirmed that the PRPF4 gene was overexpressed in various breast cancer cell lines. Next, using breast cancer cell lines MCF7 and MDA-MB-468, we established stable cell lines with PRPF4 gene knockdown. We also performed microarray analysis to investigate molecular mechanisms underlying PRPF4 activity. All cell lines with PRPF4 gene knockdown exhibited reduced cell proliferation, remarkable reduction in anchorage-independent colony formation capacity, and reduction of PCNA protein, which is a marker cell of proliferation. Reduced expression of the PRPF4 gene induced apoptosis and changes in the expression of associated apoptotic markers in breast cancer cell lines. Knockdown of the PRPF4 gene reduced cellular capacity for migration and invasion (the key hallmarks of human cancers) and decreased the expression of genes involved in epithelial-mesenchymal transition (EMT). Microarray results showed that the expression of PPIP5K1, PPIPK2, and YWHAE genes was reduced at the transcriptional level, leading to reduced phosphorylation of p38 MAPK. These findings suggest that knockdown of PRPF4 gene slows down breast cancer progression via suppression of p38 MAPK phosphorylation. In conclusion, the PRPF4 gene plays an important role in the growth of breast cancer cells and is therefore a potential therapeutic target.


Assuntos
Neoplasias da Mama/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/genética , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Células MCF-7 , Fosforilação
9.
Cell Biochem Funct ; 37(8): 608-617, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31502671

RESUMO

Mouse embryonic stem cells (mESCs) are characterized by their self-renewal and pluripotency and are capable of differentiating into all three germ layers. For this reason, mESCs are considered a very important model for stem cell research and clinical applications in regenerative medicine. The pre-mRNA processing factor 4 (PRPF4) gene is known to have a major effect on pre-mRNA splicing and is also known to affect tissue differentiation during development. In this study, we investigated the effects of PRPF4 knockdown on mESCs. First, we allowed mESCs to differentiate naturally and observed a significant decrease in PRPF4 expression during the differentiation process. We then artificially induced the knockdown of PRPF4 in mESCs and observed the changes in the phenotype. When PRPF4 was knocked down, various genes involved in mESC pluripotency showed significantly decreased expression. In addition, mESC proliferation increased abnormally, accompanied by a significant increase in mESC colony size. The formation of mESC embryoid bodies and teratomas was delayed following PRPF4 knockdown. Based on these results, the reduced expression of PRPF4 affects mESC phenotypes and is a key factor in mESC. SIGNIFICANCE OF THE STUDY: Our results indicate that PRPF4 affects the properties of mESCs. Suppression of PRPF4 resulted in a decrease in pluripotency of mESC and promoted proliferation. In addition, suppression of PRPF4 also resulted in decreased apoptosis. Moreover, the inhibition of PRPF4 reduced the ability to differentiate and formation of teratoma in mESC. Our results demonstrated that PRPF4 is a key factor of controlling mESC abilities.


Assuntos
Diferenciação Celular , Proliferação de Células , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Animais , Células Cultivadas , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/antagonistas & inibidores , Ribonucleoproteína Nuclear Pequena U4-U6/genética , Teratoma/genética , Teratoma/patologia
10.
Cell Biochem Funct ; 37(3): 139-147, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30883865

RESUMO

Lin28, which is highly expressed during embryogenesis, has been shown to play an important role in cell growth and embryonic development. Meanwhile, Lin28 represses let-7 miRNA biogenesis and block pre-let-7 processing in the cytoplasm. The let-7 family of miRNAs is known to repress oncogenesis and cell cycle progression by targeting oncogenic genes and signalling pathways. Consequently, Lin28 acts as an oncogene by upregulating let-7 targets through the repression of let-7 biogenesis. A recent genome-wide association study (GWAS) showed that many genes related to Type 2 diabetes (T2D) are also oncogenes or cell cycle regulators. The role of Lin28 in mouse growth and glucose metabolism in metabolic-related tissues has also been studied. In these studies, whole-body Lin28 overexpression was found to promote glucose utilization and prevent weight gain by inhibiting let-7 biogenesis. Furthermore, Lin28 has been found to directly stimulate skeletal myogenesis and cell growth. Therefore, we determined whether similar effects mediated by Lin28a, which is essential for cell growth and proliferation, may also apply to pancreatic ß-cells. We found that overexpression of Lin28a protects pancreatic ß-cells from streptozotocin (STZ)-induced ß-cell destruction in vitro and in vivo. Furthermore, Lin28a-overexpressing transgenic (Tg) mice had higher insulin secretion in the presence of glucose than in control mice. Our findings suggest that the Lin28/let-7 axis is an important regulator of pancreatic ß-cell functions and that precise modulation of this axis may be helpful in treating metabolic diseases such as diabetes. SIGNIFICANCE OF THE STUDY: We demonstrate that Lin28a prevents pancreatic ß-cell death against streptozotocin (STZ)-induced ß-cell destruction in vitro and in vivo. Furthermore, Lin28a promotes cell survival and proliferation by activating the PI3K-Akt signalling pathway, which may be dependent on let-7 regulation. Taken together, our results imply that the Lin28a/let-7 axis is an important regulator of pancreatic ß-cell functions and that precise modulation of this axis may be helpful in treating metabolic diseases such as diabetes.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Células Secretoras de Insulina/efeitos dos fármacos , Proteínas de Ligação a RNA/genética , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Células Secretoras de Insulina/patologia , Masculino , Camundongos , Proteínas de Ligação a RNA/metabolismo , Estreptozocina , Células Tumorais Cultivadas
11.
Endocr J ; 65(4): 437-447, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29434073

RESUMO

Placental growth factor (PlGF), a member of the vascular endothelial growth factor (VEGF) sub-family, plays a major role in angiogenesis and vasculogenesis. Previous study demonstrated that PlGF-overexpressing transgenic (Tg) mice had gestational loss. In addition, PlGF secretion was up-regulated in isolated T lymphocytes (T-cell) upon CD3/CD28 stimulation, suggesting that PlGF could be a regulator of T-cell differentiation and development. T-cells are well known to play a critical role in obesity-induced inflammation. Therefore, to verify the possible link of diet-induced obesity (DIO) with inflammation and related metabolic disorders, such as insulin resistance, we fed high-fat diet (HFD) to Tg mice for 16 weeks. Adiposity and glucose intolerance significantly increase in Tg mice fed a HFD (Tg HFD) compared to wild-type (WT) mice fed HFD (WT HFD). In addition, macrophage infiltrations were significantly higher in the epididymal white adipose tissue (EWAT), liver, and pancreatic islets of Tg HFD mice compared to WT HFD mice. In the in vitro study, we showed that isolated CD4+ T-cells from Tg mice further differentiate into type 1 (Th1) and type 17 (Th17) helper T-cells via CD3/CD28 stimulation. Furthermore, we observed that the pro-inflammatory cytokines IL-6, IL-17, and TNFα, are remarkably increased in Tg mice compared to WT mice. These findings demonstrate that PlGF overexpression in T-cells might lead to inflammatory T-cell differentiation and accumulation in adipose tissue (AT) or metabolism-related tissues, contributing to the development of systemic metabolic disorders. Thus, PlGF may provide an effective therapeutic target in the management of obesity-induced inflammation and related metabolic disorders.


Assuntos
Citocinas/biossíntese , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Obesidade/metabolismo , Fator de Crescimento Placentário/metabolismo , Adiposidade/fisiologia , Animais , Inflamação/genética , Resistência à Insulina/fisiologia , Camundongos , Camundongos Transgênicos , Obesidade/etiologia , Fator de Crescimento Placentário/genética
12.
Cell Biochem Funct ; 35(7): 392-400, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28895148

RESUMO

Induced pluripotent stem (iPS) cells are important for clinical application and stem cell research. Although human melanoma-associated antigen A2 (hMAGEA2) expression is known to affect differentiation in embryonic stem cells, its specific role in iPS cells remains unclear. To evaluate the function of hMAGEA2 and its characteristics in iPS cells, we produced hMAGEA2-overexpressing iPS cells from hMAGEA2-overexpressing transgenic mice. Although the iPS cells with overexpressed hMAGEA2 did not differ in morphology, their pluripotency, and self-renewal related genes (Nanog, Oct3/4, Sox2, and Stat3), expression level was significantly upregulated. Moreover, hMAGEA2 contributed to the promotion of cell cycle progression, thereby accelerating cell proliferation. Through embryoid body formation in vitro and teratoma formation in vivo, we demonstrated that hMAGEA2 critically decreases the differentiation ability of iPS cells. These data indicate that hMAGEA2 intensifies the self-renewal, pluripotency, and degree of proliferation of iPS cells, while significantly repressing their differentiation efficiency. Therefore, our findings prove that hMAGEA2 plays key roles in iPS cells.


Assuntos
Diferenciação Celular , Proliferação de Células , Células-Tronco Pluripotentes Induzidas/metabolismo , Antígenos Específicos de Melanoma/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Células Cultivadas , Corpos Embrioides/metabolismo , Corpos Embrioides/patologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Genótipo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/transplante , Masculino , Antígenos Específicos de Melanoma/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Retroviridae/genética , Teratoma/metabolismo , Teratoma/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
Biochem Biophys Res Commun ; 471(4): 437-43, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26902115

RESUMO

Epigenetic mechanisms are relevant to development and contribute to fetal neurogenesis. DNA methylation and demethylation contribute to neural gene expression during mouse brain development. Ten-eleven translocation 1 (TET1) regulates DNA demethylation by converting 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). TET1 specifically regulates 5hmC in the central nervous system (CNS), including during neurogenesis in the adult brain. However little is known about its function in fetal neurogenesis. In order to evaluate the role of TET1 in fetal brain development, we generated TET1-overexpressing transgenic (TG) mice. TET1 overexpression was confirmed in the brains of fetal mice, and we detected 5hmC overexpression in the TG brains compared to that in the wild type (WT) brains, using a dot-blot assay. In order to observe the role of TET1 in fetal brain development, we examined fetal brain samples at varied time points by using real-time PCR, Western blotting, and Immunofluorescence (IF). We confirmed that TET1 contributes to neurogenesis by upregulating the protein expressions of neuronal markers in the TG mouse brains, as determined by Western blotting. However the cortex structure or brain mass between WT and TG mice showed no significant difference by IF. In conclusion, TET1 makes the start time of neurogenesis earlier in the TG brains compared to that in the WT brains during fetal brain development.


Assuntos
Encéfalo/embriologia , Proteínas de Ligação a DNA/metabolismo , Neurogênese/genética , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/análogos & derivados , Animais , Biomarcadores/metabolismo , Encéfalo/metabolismo , Citosina/análogos & derivados , Citosina/metabolismo , Proteínas de Ligação a DNA/genética , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Vetores Genéticos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/fisiologia , Proteínas Proto-Oncogênicas/genética , Reação em Cadeia da Polimerase em Tempo Real
14.
Differentiation ; 89(1-2): 42-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25766428

RESUMO

Mouse embryonic stem cells (ESCs) are self-renewing, pluripotent, and have the ability to differentiate into the three germ layers required to form all embryonic tissues. These properties are maintained by both intrinsic and extrinsic factors. Many studies have contributed to the understanding of the molecular signal transduction required for pluripotency and controlled differentiation. Such an understanding is important in the potential application of stem cells to cell therapy for disease, and thus there is an interest in understanding the cell cycle regulation, pluripotency, and differentiation of ESCs. The regulator of G protein signaling (RGS) family consists of over 20 members. Rgs19, one such protein, specifically interacts with Gαi to enhance its GTPase activity. Growth factor receptors use Gi proteins for signal transduction, and Rgs19 may thus be involved in the regulation of cell proliferation. In a previous gain-of-function study, Rgs19 overexpression was found to enhance proliferation in various cell types. Our data demonstrate a role for Rgs19 in the regulation of ESC differentiation. Based on the presence of Rgs19 in ESCs, the morphological and molecular properties of wild-type and Rgs19 +/- ESCs during LIF withdrawal, in vitro differentiation, and teratoma formation were compared. Our findings provide insight for the first time into the mechanisms involved in Rgs19 regulation of mouse ESC proliferation and differentiation.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Células-Tronco Embrionárias Murinas , Proteínas RGS/genética , Animais , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Proteínas RGS/biossíntese , Transdução de Sinais
15.
Arterioscler Thromb Vasc Biol ; 34(10): 2276-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25147341

RESUMO

OBJECTIVE: Angiogenesis is an important biological process during development, reproduction, and in immune responses. Placental growth factor (PlGF) is a member of vascular endothelial growth factor that is critical for angiogenesis and vasculogenesis. We generated transgenic mice overexpressing PlGF in specifically T cells using the human CD2-promoter to investigate the effects of PlGF overexpression. APPROACH AND RESULTS: Transgenic mice were difficult to obtain owing to high lethality; for this reason, we investigated why gestational loss occurred in these transgenic mice. Here, we report that placenta detachment and inhibition of angiogenesis occurred in PlGF transgenic mice during the gestational period. Moreover, even when transgenic mice were born, their growth was restricted. CONCLUSIONS: Conclusively, PlGF overexpression prevents angiogenesis by inhibiting Braf, extracellular signal-regulated kinase activation, and downregulation of HIF-1α in the mouse placenta. Furthermore, it affected regulatory T cells, which are important for maintenance of pregnancy.


Assuntos
Morte Fetal/metabolismo , Retardo do Crescimento Fetal/metabolismo , Neovascularização Fisiológica , Placenta/irrigação sanguínea , Placenta/metabolismo , Proteínas da Gravidez/metabolismo , Linfócitos T Reguladores/metabolismo , Animais , Peso Corporal , Antígenos CD2/genética , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Morte Fetal/genética , Morte Fetal/fisiopatologia , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Tamanho da Ninhada de Vivíparos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator de Crescimento Placentário , Gravidez , Proteínas da Gravidez/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais , Regulação para Cima
16.
Biochem Biophys Res Commun ; 452(3): 822-7, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25201726

RESUMO

Chronic hepatitis is a major cause of liver cancer, so earlier treatment of hepatitis might be reducing liver cancer incidence. Hepatitis can be induced in mice by treatment with Concanavalin A (Con A); the resulting liver injury causes significant CD4(+) T cell activation and infiltration. In these T cells, Roquin, a ring-type E3 ubiquitin ligase, is activated. To investigate the role of Roquin, we examined Con A-induced liver injury and T cell infiltration in transgenic (Tg) mice overexpressing Roquin specifically in T cells. In Roquin Tg mice, Con A treatment caused greater increases in both the levels of liver injury enzymes and liver tissue apoptosis, as revealed by TUNEL and H&E staining, than wild type (WT) mice. Further, Roquin Tg mice respond to Con A treatment with greater increases in the T cell population, particularly Th17 cells, though Treg cell counts are lower. Roquin overexpression also enhances increases in pro-inflammatory cytokines, including IFN-γ, TNF-α and IL-6, upon liver injury. Furthermore, Roquin regulates the immune response and apoptosis in Con A induced hepatitis via STATs, Bax and Bcl2. These findings suggest that over-expression of Roquin exacerbates T-cell mediated hepatitis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/genética , Hepatócitos/metabolismo , Regiões Promotoras Genéticas , Células Th17/metabolismo , Ubiquitina-Proteína Ligases/genética , Animais , Apoptose , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A , Feminino , Regulação da Expressão Gênica , Hepatócitos/patologia , Interferon gama/biossíntese , Interferon gama/metabolismo , Interleucina-6/biossíntese , Interleucina-6/metabolismo , Ativação Linfocitária , Contagem de Linfócitos , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Células Th17/patologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
17.
Front Cell Infect Microbiol ; 13: 1230568, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829606

RESUMO

Introduction: Diabetes mellitus (DM) impairs fracture healing and is associated with susceptibility to infection, which further inhibits fracture healing. While intermittent parathyroid hormone (1-34) (iPTH) effectively improves fracture healing, it is unknown whether infection-associated impaired fracture healing can be rescued with PTH (teriparatide). Methods: A chronic diet-induced type 2 diabetic mouse model was used to yield mice with decreased glucose tolerance and increased blood glucose levels compared to lean-fed controls. Methicillin-resistant Staphylococcus aureus (MRSA) was inoculated in a surgical tibia fracture model to simulate infected fracture, after which mice were treated with a combination of antibiotics and adjunctive teriparatide treatment. Fracture healing was assessed by Radiographic Union Scale in Tibial Fractures (RUST), micro-computed tomography (µCT), biomechanical testing, and histology. Results: RUST score was significantly poorer in diabetic mice compared to their lean nondiabetic counterparts. There were concomitant reductions in micro-computed tomography (µCT) parameters of callus architecture including bone volume/total volume, trabecular thickness, and total mineral density in type 2 diabetes mellitus (T2DM) mice. Biomechanicaltesting of fractured femora demonstrated diminished torsional rigidity, stiffness, and toughness to max torque. Adjuvant teriparatide treatment with systemic antibiotic therapy improved numerous parameters of bone microarchitecture bone volume, increased connectivity density, and increased trabecular number in both the lean and T2DM group. Despite the observation that poor fracture healing in T2DM mice was further impaired by MRSA infection, adjuvant iPTH treatment significantly improved fracture healing compared to antibiotic treatment alone in infected T2DM fractures. Discussion: Our results suggest that teriparatide may constitute a viable adjuvant therapeutic agent to improve bony union and bone microarchitecture to prevent the development of septic nonunion under diabetic conditions.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Staphylococcus aureus Resistente à Meticilina , Camundongos , Animais , Consolidação da Fratura , Teriparatida/uso terapêutico , Teriparatida/farmacologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Microtomografia por Raio-X , Hormônio Paratireóideo/farmacologia , Hormônio Paratireóideo/uso terapêutico
18.
Am J Chin Med ; 51(5): 1309-1333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37385965

RESUMO

Prostate cancer (PC) is the second leading cause of cancer-related death among men. Treatment of PC becomes difficult after progression because PC that used to be androgen-dependent becomes androgen-independent prostate cancer (AIPC). Veratramine, an alkaloid extracted from the root of the Veratrum genus, has recently been reported to have anticancer effects that work against various cancers; however, its anticancer effects and the underlying mechanism of action in PC remain unknown. We investigated the anticancer effects of veratramine on AIPC using PC3 and DU145 cell lines, as well as a xenograft mouse model. The antitumor effects of veratramine were evaluated using the CCK-8, anchorage-independent colony formation, trans-well, wound healing assays, and flow cytometry in AIPC cell lines. Microarray and proteomics analyses were performed to investigate the differentially expressed genes and proteins induced by veratramine in AIPC cells. A xenograft mouse model was used to confirm the therapeutic response and in vivo efficacy of veratramine. Veratramine dose dependently reduced the proliferation of cancer cells both in vitro and in vivo. Moreover, veratramine treatment effectively suppressed the migration and invasion of PC cells. The immunoblot analysis revealed that veratramine significantly downregulated Cdk4/6 and cyclin D1 via the ATM/ATR and Akt pathways, both of which induce a DNA damage response that eventually leads to G1 phase arrest. In this study, we discovered that veratramine exerted antitumor effects on AIPC cells. We demonstrated that veratramine significantly inhibited the proliferation of cancer cells via G0/G1 phase arrest induced by the ATM/ATR and Akt pathways. These results suggest that veratramine is a promising natural therapeutic agent for AIPC.


Assuntos
Androgênios , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Androgênios/farmacologia , Androgênios/uso terapêutico , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ciclo Celular , Linhagem Celular Tumoral , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/farmacologia
19.
Cell Mol Gastroenterol Hepatol ; 11(4): 1139-1161, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33340713

RESUMO

BACKGROUND: Dysfunction of liver sinusoidal endothelial cells (LSECs) is permissive for the progression of liver fibrosis and cirrhosis and responsible for its clinical complications. Here, we have mapped the spatial distribution of heterogeneous liver ECs in normal vs cirrhotic mouse livers and identified zone-specific transcriptomic changes of LSECs associated with liver cirrhosis using scRNA-seq technology. APPROACH & RESULTS: Cirrhosis was generated in endothelial specific green fluorescent protein (GFP) reporter mice through carbon tetrachloride inhalation for 12 weeks. GFP-positive liver EC populations were isolated from control and cirrhotic mice by FACS. We identified 6 clusters of liver EC populations including 3 clusters of LSECs, 2 clusters of vascular ECs and 1 cluster of lymphatic ECs. Based on previously reported LSEC-landmarks, we mapped the 3 clusters of LSECs in zones 1, 2, and 3, and determined phenotypic changes in each zone between control and cirrhotic mice. We found genes representing capillarization of LSECs (eg, CD34) as well as extracellular matrix genes were most upregulated in LSECs of zone 3 in cirrhotic mice, which may contribute to the development of basement membranes. LSECs in cirrhotic mice also demonstrated decreased expression of endocytic receptors, most remarkably in zone 3. Transcription factors (Klf2 [Kruppel-like factor-2], Klf4 [Kruppel-like factor-4], and AP-1) that induce nitric oxide production in response to shear stress were downregulated in LSECs of all zones in cirrhotic mice, implying increased intrahepatic vascular resistance. CONCLUSION: This study deepens our knowledge of the pathogenesis of liver cirrhosis at a spatial, cell-specific level, which is indispensable for the development of novel therapeutic strategies to target the most dysfunctional liver ECs.


Assuntos
Capilares/patologia , Células Endoteliais/patologia , Regulação da Expressão Gênica , Cirrose Hepática/genética , Cirrose Hepática/patologia , Análise de Célula Única/métodos , Transcriptoma , Animais , Capilares/metabolismo , Tetracloreto de Carbono/toxicidade , Células Endoteliais/metabolismo , Cirrose Hepática/induzido quimicamente , Camundongos
20.
FEBS J ; 288(14): 4412-4427, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33555104

RESUMO

Genetic susceptibility of type 2 diabetes and Juxtaposed with another zinc finger protein 1 (Jazf1) has been reported; however, the precise role of Jazf1 in metabolic processes remains elusive. In this study, using Jazf1-knockout (KO)-induced pluripotent stem cells (iPSC), pancreatic beta cell line MIN6 cells, and Jazf-1 heterozygous KO (Jazf1+/- ) mice, the effect of Jazf1 on gradual differentiation was investigated. We checked the alterations of the genes related with ß-cell specification, maturation, and insulin release against glucose treatment by the gain and loss of the Jazf1 gene in the MIN6 cells. Because undifferentiated Jazf1-KO iPSC were not significantly different from wild-type (WT) iPSC, the size and endoderm marker expression after embryoid body (EB) and teratoma formation were investigated. Compared to EB and teratomas formed with WT iPSC, the EB and teratomas from with Jazf1-KO iPSC were smaller, and in teratomas, the expression of proliferation markers was reduced. Moreover, the expression of the gene sets for ß-cell differentiation and the levels of insulin and C-peptide secreted by insulin precursor cells were notably reduced in ß-cells differentiated from Jazf1-KO iPSC compared with those differentiated from WT iPSC. A comparison of Jazf1+/- and WT mice showed that Jazf1+/- mice had lower levels of serum insulin, pancreatic insulin expression, and decreased pancreatic ß-cell size, which resulted in defects in the glucose homeostasis. These findings suggest that Jazf1 plays a pivotal role in the differentiation of ß-cells and glucose homeostasis.


Assuntos
Diferenciação Celular , Proteínas Correpressoras/fisiologia , Proteínas de Ligação a DNA/fisiologia , Glucose/metabolismo , Homeostase , Células-Tronco Pluripotentes Induzidas/citologia , Células Secretoras de Insulina/citologia , Insulina/metabolismo , Animais , Células Cultivadas , Feminino , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Organogênese
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