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1.
Arq. bras. cardiol ; 107(6): 532-541, Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-838658

ABSTRACT

Abstract Background: Impaired angiogenesis in cardiac tissue is a major complication of diabetes. Protein kinase B (AKT) and extracellular signal regulated kinase (ERK) signaling pathways play important role during capillary-like network formation in angiogenesis process. Objectives: To determine the effects of testosterone and voluntary exercise on levels of vascularity, phosphorylated Akt (P- AKT) and phosphorylated ERK (P-ERK) in heart tissue of diabetic and castrated diabetic rats. Methods: Type I diabetes was induced by i.p injection of 50 mg/kg of streptozotocin in animals. After 42 days of treatment with testosterone (2mg/kg/day) or voluntary exercise alone or in combination, heart tissue samples were collected and used for histological evaluation and determination of P-AKT and P-ERK levels by ELISA method. Results: Our results showed that either testosterone or exercise increased capillarity, P-AKT, and P-ERK levels in the heart of diabetic rats. Treatment of diabetic rats with testosterone and exercise had a synergistic effect on capillarity, P-AKT, and P-ERK levels in heart. Furthermore, in the castrated diabetes group, capillarity, P-AKT, and P-ERK levels significantly decreased in the heart, whereas either testosterone treatment or exercise training reversed these effects. Also, simultaneous treatment of castrated diabetic rats with testosterone and exercise had an additive effect on P-AKT and P-ERK levels. Conclusion: Our findings suggest that testosterone and exercise alone or together can increase angiogenesis in the heart of diabetic and castrated diabetic rats. The proangiogenesis effects of testosterone and exercise are associated with the enhanced activation of AKT and ERK1/2 in heart tissue.


Resumo Fundamento: Angiogênese prejudicada em tecido cardíaco é uma das principais complicações das diabetes. As vias de sinalização da proteína-quinase B (AKT) e a quinase regulada por sinal extracelular (ERK) exercem um importante papel durante a formação de uma rede similar à capilar no processo de angiogênese. Objetivos: Determinar os efeitos da testosterona e exercícios voluntários sobre os níveis de vascularidade, AKT fosforilada (P- AKT) e ERK fosforilada (P-ERK) sobre o tecido cardíaco de ratos diabéticos e castrados diabéticos. Métodos: A diabetes tipo 1 foi induzida através de injeção intraperitoneal de 50 mg/kg de estreptozotocina em animais. Após 42 dias de tratamento com testosterona (2mg/kg/dia) ou exercícios voluntários, individualmente ou em conjunto, as amostras de tecidos cardíacos foram coletadas e usadas para avaliação histológica e determinação de níveis de P-AKT e P-ERK através do método ELISA. Resultados: Os nossos resultados mostraram que a testosterona ou os exercícios aumentaram a capilaridade, os níveis de P-AKT, e P-ERK nos corações de ratos diabéticos. O tratamento de ratos diabéticos com testosterona e exercícios obteve um efeito sinérgico sobre a capilaridade, níveis de P-AKT, e P-ERK no coração. Além disto, na capilaridade do grupo diabético castrado, os níveis de P-AKT e P-ERK diminuíram significativamente no coração, ao passo que o tratamento com testosterona ou o treinamento com exercícios reverteu tais efeitos. O tratamento simultâneo de ratos diabéticos castrados com testosterona e exercícios obteve um efeito aditivo sobre os níveis de P-AKT e P-ERK. Conclusão: Nossas descobertas sugerem que a testosterona e exercícios, em conjunto ou individualmente, podem aumentar a angiogênese nos corações de ratos diabéticos e castrados diabéticos. Os efeitos favoráveis à angiogênese da testosterona e dos exercícios estão associados à ativação reforçada de AKT e ERK1/2 no tecido cardíaco.


Subject(s)
Animals , Male , Physical Conditioning, Animal/physiology , Testosterone/pharmacology , Extracellular Signal-Regulated MAP Kinases/analysis , Diabetes Mellitus, Experimental/metabolism , Heart/drug effects , Androgens/pharmacology , Time Factors , Enzyme-Linked Immunosorbent Assay , Signal Transduction/drug effects , Reproducibility of Results , Rats, Wistar , Hormone Replacement Therapy/methods , Extracellular Signal-Regulated MAP Kinases/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 1/physiopathology , Diabetes Mellitus, Type 1/metabolism , Heart/physiopathology , Androgens/therapeutic use , Myocardium/chemistry
2.
Clin. biomed. res ; 36(4): 254-256, 2016. ilus, graf
Article in English | LILACS | ID: biblio-831840

ABSTRACT

We investigated the influence of bone marrow cells upon activation of ERK 1/2 in an animal model of 90% PH. Phosphorylated ERK 1/2 was evaluated by western blot. No differences were found between the groups. Thus, increased survival does not appear to be mediated by ERK 1/2 activation (AU)


Subject(s)
Animals , Rats , Bone Marrow Transplantation , Extracellular Signal-Regulated MAP Kinases/metabolism , Liver Failure, Acute/therapy , Disease Models, Animal , Enzyme Activation/physiology , Hepatectomy , Survival Rate
3.
Yonsei Medical Journal ; : 761-768, 2016.
Article in English | WPRIM | ID: wpr-205738

ABSTRACT

PURPOSE: Our previous studies have shown that oncostatin M (OSM) promotes trophoblast invasion activity through increased enzyme activity of matrix metalloproteinase (MMP)-2 and -9. We further investigated OSM-induced intracellular signaling mechanisms associated with these events in the immortalized human trophoblast cell line HTR8/SVneo. MATERIALS AND METHODS: We investigated the effects of OSM on RNA and protein expression of MMP-2 and -9 in the first-trimester extravillous trophoblast cell line (HTR8/SVneo) via Western blot. The selective signal transducer and activator of transcription (STAT)3 inhibitor, stattic, STAT3 siRNA, and extracellular signal-regulated kinase (ERK) siRNA were used to investigate STAT3 and ERK activation by OSM. The effects of STAT3 and ERK inhibitors on OSM-induced enzymatic activities of MMP-2 and -9 and invasion activity were further determined via Western blot and gelatin zymography. RESULTS: OSM-induced MMP-2 and -9 protein expression was significantly suppressed by STAT3 inhibition with stattic and STAT3 siRNA silencing, whereas the ERK1/2 inhibitor (U0126) and ERK silencing significantly suppressed OSM-induced MMP-2 protein expression. OSM-induced MMP-2 and MMP-9 enzymatic activities were significantly decreased by stattic pretreatment. The increased invasion activity induced by OSM was significantly suppressed by STAT3 and ERK1/2 inhibition, though to a greater extent by STAT3 inhibition. CONCLUSION: Both STAT3 and ERK signaling pathways are involved in OSM-induced invasion activity of HTR8/SVneo cells. Activation of STAT3 appears to be critical for the OSM-mediated increase in invasiveness of HTR8/SVneo cells.


Subject(s)
Blotting, Western , Cell Movement/drug effects , Cell Proliferation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 9/genetics , Oncostatin M/genetics , Phosphorylation/drug effects , RNA, Messenger/metabolism , RNA, Small Interfering , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects
4.
Yonsei Medical Journal ; : 33-40, 2016.
Article in English | WPRIM | ID: wpr-199916

ABSTRACT

PURPOSE: This study aimed to investigate whether Mullerian inhibiting substance (MIS) in combination with calcitriol modulates proliferation and apoptosis of human ovarian cancer (OCa) cell lines (SKOV3, OVCAR3, and OVCA433) and identify the signaling pathway by which MIS mediates apoptosis. MATERIALS AND METHODS: OCa cell lines were treated with MIS in the absence or presence of calcitriol. Cell viability and proliferation were evaluated using the Cell Counting Kit-8 assay and apoptosis was evaluated by DNA fragmentation assay. Western blot and enzyme-linked immunosorbent assay were used to determine the signaling pathway. RESULTS: The cells showed specific staining for the MIS type II receptor. Treatment of OCa cells with MIS and calcitriol led to dose- and time-dependent inhibition of cell growth and survival. The combination treatment significantly suppressed cell growth, down-regulated the expression of B-cell lymphoma 2 (Bcl-2), and up-regulated the expressions of Bcl-2 associated X protein, caspase-3, and caspase-9 through the extracellular signal-regulated kinase signaling pathway. CONCLUSION: These results, coupled with a much-needed decrease in the toxic side effects of currently employed therapeutic agents, provide a strong rationale for testing the therapeutic potential of MIS, alone or in combination with calcitriol, in the treatment of OCa.


Subject(s)
Anti-Mullerian Hormone/pharmacology , Apoptosis/drug effects , Calcitriol/pharmacology , Caspase 3/metabolism , Caspase 9/metabolism , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , DNA Fragmentation/drug effects , Enzyme-Linked Immunosorbent Assay , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Growth Inhibitors/metabolism , Humans , Ovarian Neoplasms/drug therapy , Receptors, Peptide , Receptors, Transforming Growth Factor beta , Signal Transduction/drug effects
5.
J. pediatr. (Rio J.) ; 91(2): 196-205, Mar-Apr/2015. tab
Article in English | LILACS | ID: lil-745942

ABSTRACT

OBJECTIVE: This study aimed to evaluate the association of junk food consumption with hypertension and obesity in a national sample of Iranian children and adolescents. METHODS: This nationwide study was conducted in 2011-2012 among 14,880 students, aged 6-18 years, selected by cluster sampling from 30 provinces. Weight, height, waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), as well as systolic and diastolic blood pressure (BP) were measured. Junk food was divided into four categories, including salty snacks, sweets, sweetened beverages, and fast food. Subjects reported how many times they had consumed each item (daily, weekly, and seldom). RESULTS: The intake of sweets was significantly associated with anthropometric indices and BP levels. Moreover, a significant association was found between fast food consumption, BP levels, and anthropometric indices (except for WHtR and WHR). Sweet beverages consumption was significantly associated with anthropometric indices; however, the consumption of salty snacks was only significantly associated with height, HC, and WHR. The risk of general obesity (OR: 0.75, 95% CI: 0.65-0.87) and abdominal obesity (OR: 0.81, 95% CI: 0.72-0.92) among participants who seldom consumed sweets was less than those who consumed daily. Also, the risk of general obesity (OR: 0.85, 95% CI: 0.74-0.97) among students that seldom consumed sweetened beverages was less than subjects who consumed them on a daily basis. CONCLUSION: It was found that junk food consumption increased the risk of both general and abdominal obesity; therefore, consumption of junk food should be reduced via restricting TV advertisements and increasing taxes on junk foods. .


OBJETIVO: Avaliar a associação entre o consumo de junk food e a hipertensão e obesidade em uma amostra nacional de crianças e adolescentes iranianos. MÉTODOS: Este estudo nacional foi feito entre 2011 e 2012 com 14.880 estudantes com seis-18 anos, selecionados por amostra em bloco em 30 províncias. Foram medidos o peso, a estatura, a circunferência da cintura (CC), a circunferência do quadril (CQ), a razão cintura/quadril (RCQ), a razão cintura/estatura (RCE) e a pressão arterial sistólica e diastólica (PAS e PAD). A junk food foi dividida em quatro categorias, incluindo lanches salgados, doces, bebidas açucaradas e fast food. Os indivíduos relataram quantas vezes consumiam cada um dos itens (diariamente, semanalmente, raramente). RESULTADOS: O consumo de doces foi associado significativamente aos índices antropométricos e níveis de pressão arterial (PA). Além disso, havia uma associação significativa entre o consumo de fast food e os níveis de PA e os índices antropométricos (exceto RCE e RCQ). O consumo de bebidas açucaradas foi associado significativamente aos índices antropométricos, porém o consumo de lanches salgados foi associado significativamente apenas a estatura, CQ e RCQ. O risco de obesidade geral (RC: 0,75, IC de 95%: 0,65-0,87) e obesidade abdominal (RC: 0,81, IC de 95%: 0,72-0,92) entre participantes que raramente consumiam doces era menor do que naqueles que os consumiam diariamente. Além disso, o risco de obesidade geral (RC: 0,85; IC de 95%: 0,74-0,97) entre estudantes que raramente consumiam bebidas açucaradas era menor do que entre indivíduos que os consumiam diariamente. CONCLUSÃO: Constatamos que o consumo de junk food aumentou o risco de obesidade geral e abdominal; portanto, o consumo de junk food deve ser reduzido por meio da restrição de comerciais de TV e do aumento de impostos sobre esse tipo de alimento. .


Subject(s)
Female , Humans , Autophagy , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Intercellular Signaling Peptides and Proteins/metabolism , Signal Transduction , Stress, Physiological , Biomarkers, Tumor/metabolism , Amino Acid Sequence , Breast Neoplasms/enzymology , Environment , Extracellular Signal-Regulated MAP Kinases/metabolism , /metabolism , Molecular Sequence Data , Phosphorylation , Protein Biosynthesis , /metabolism , Phosphopeptides/chemistry , Phosphopeptides/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Temperature
7.
Article in English | WPRIM | ID: wpr-220401

ABSTRACT

Fucoidan has attracted attention as a potential drug because of its biological activities, which include osteogenesis. However, the molecular mechanisms involved in the osteogenic activity of fucoidan in human alveolar bone marrow-derived mesenchymal stem cells (hABM-MSCs) remain largely unknown. We investigated the action of fucoidan on osteoblast differentiation in hABM-MSCs and its impact on signaling pathways. Its effect on proliferation was determined using the crystal violet staining assay. Osteoblast differentiation was evaluated based on alkaline phosphatase (ALP) activity and the mRNA expression of multiple osteoblast markers. Calcium accumulation was determined by Alizarin red S staining. We found that fucoidan induced hABM-MSC proliferation. It also significantly increased ALP activity, calcium accumulation and the expression of osteoblast-specific genes, such as ALP, runt-related transcription factor 2, type I collagen-alpha 1 and osteocalcin. Moreover, fucoidan induced the expression of bone morphogenetic protein 2 (BMP2) and stimulated the activation of extracellular signal-related kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase by increasing phosphorylation. However, the effect of fucoidan on osteogenic differentiation was inhibited by specific inhibitors of ERK (PD98059) and JNK (SP600125) but not p38 (SB203580). Fucoidan enhanced BMP2 expression and Smad 1/5/8, ERK and JNK phosphorylation. Moreover, the effect of fucoidan on osteoblast differentiation was diminished by BMP2 knockdown. These results indicate that fucoidan induces osteoblast differentiation through BMP2-Smad 1/5/8 signaling by activating ERK and JNK, elucidating the molecular basis of the osteogenic effects of fucoidan in hABM-MSCs.


Subject(s)
Bone Morphogenetic Protein 2/genetics , Calcium/metabolism , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation/drug effects , Gene Knockdown Techniques , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Mesenchymal Stem Cells/cytology , Osteoblasts/cytology , Osteogenesis/drug effects , Phosphorylation , Polysaccharides/pharmacology , Protein Kinase Inhibitors/pharmacology , RNA, Messenger/genetics , Signal Transduction/drug effects , Smad Proteins/metabolism
8.
Article in English | WPRIM | ID: wpr-70183

ABSTRACT

Angiogenesis, the formation of new blood vessels, is critical for tumor growth and metastasis. Notably, tumors themselves can lead to angiogenesis by inducing vascular endothelial growth factor (VEGF), which is one of the most potent angiogenic factors. Inhibition of angiogenesis is currently perceived as one of the most promising strategies for the blockage of tumor growth. In this study, we investigated the effects of Acer tegmentosum maxim water extract (ATME) on angiogenesis and its underlying signal mechanism. We studied the antiangiogenic activity of ATME by using human umbilical vein endothelial cells (HUVECs). ATME strongly inhibited VEGF-induced endothelial cell proliferation, migration, invasion, and tube formation, as well as vessel sprouting in a rat aortic ring sprouting assay. Moreover, we found that the p44/42 mitogen activated protein (MAP) kinase signaling pathway is involved in the inhibition of angiogenesis by ATME. Moreover, when we performed the in vivo matrigel plug assay, VEGF-induced angiogenesis was potently reduced when compared to that for the control group. Taken together, these results suggest that ATME exhibits potent antiangiogenic activity in vivo and in vitro and that these effects are regulated by the extracellular regulated kinase (ERK) pathway.


Subject(s)
Acer/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Cell Survival , Extracellular Signal-Regulated MAP Kinases/metabolism , Hep G2 Cells , Human Umbilical Vein Endothelial Cells/drug effects , Humans , MAP Kinase Signaling System/drug effects , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase 1/metabolism , Neoplasm Invasiveness/pathology , Neovascularization, Pathologic/drug therapy , Nitric Oxide Synthase Type III/metabolism , Phosphorylation/drug effects , Plant Extracts/pharmacology , Rats , Rats, Sprague-Dawley , Transcription Factors/metabolism , Vascular Endothelial Growth Factor A/antagonists & inhibitors
9.
Acta cir. bras ; 29(10): 644-650, 10/2014. tab, graf
Article in English | LILACS | ID: lil-725295

ABSTRACT

PURPOSE: To evaluate the alterations of two mitogen-activated protein kinases (MAPK)s, extracellular signal regulated kinase (ERK) and c-Jun NH2 terminal kinase (JNK), in the testes of male rats with experimental diabetes. METHODS: Twenty males Sprague-Dawley rats were randomly divided into a control group (n=8) and a diabetes group (administration of 40 mg/kg/day streptozotocin (STZ) for five sequential days, n=12). After six weeks, testicular biopsy samples were obtained for light microscopy and immunohistochemical methods. RESULTS: The PCNA (proliferating cell nuclear antigen) index was significantly decreased in the diabetes group (p=0.004) when compared to the control group. Both total (t)-ERK and phosphor (p)-ERK immunoreactivities were significantly decreased in the diabetes group (p=0.004, p<0.001, respectively). The t-JNK immunoreactivity was unchanged in both groups (p=0.125), while p-JNK immunoreactivity was significantly increased in the diabetic group (p=0.002). CONCLUSIONS: The decrease of androgen levels in the course of diabetes may contribute to the decrease of the immunoreactivities of t-ERK and p-ERK. JNK may be activated due to the changes in various cytokines and chemochines that participate in the oxidative stress process of diabetes. Therefore, testicular apoptosis may occur and lead to infertility associated with diabetes. .


Subject(s)
Animals , Male , Diabetes Mellitus, Experimental/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Testis/metabolism , Apoptosis , Biopsy , Diabetes Mellitus, Experimental/complications , Immunohistochemistry , Infertility, Male/etiology , Infertility, Male/metabolism , Random Allocation , Rats, Wistar , Streptozocin , Testis/pathology
10.
Article in English | WPRIM | ID: wpr-191059

ABSTRACT

Wound healing is initiated and progressed by complex integrated process of cellular, physiologic, and biochemical events, such as inflammation, cell migration and proliferation. Interleukin 6 (IL-6) is a multifunctional cytokine, and it could regulate the inflammatory response of wound healing process in a timely manner. Hyaluronic acid (HA) is an essential component of the extracellular matrix, and contributes significantly to cell proliferation and migration. The purpose of this study was to investigate the effects of IL-6 or/and HA on the cell migration process in human keratinocytes. Combining IL-6 and HA significantly increased the cell migration in scratch based wound healing assay. The phosphorylation of extracellular-signal-regulated kinase (ERK) was significantly increased after 1 hr of IL-6 and HA treatment, but the phosphorylation of p38 mitogen-activated protein kinase (MAPK) was not. We also found that significant increase of the NF-kappaB translocation from cytoplasm into nucleus after 1 hr of IL-6 or/and HA treatments. This study firstly showed that synergistic effects of combining IL-6 and HA on the cell migration of wound healing by activation of ERK and NF-kappaB signaling. Further studies might be required to confirm the synergistic effects of HA and IL-6 in the animal model for the development of a novel therapeutic mixture for stimulation of wound healing process.


Subject(s)
Active Transport, Cell Nucleus/drug effects , Cell Line , Cell Movement/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Enzyme Activation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Hyaluronic Acid/pharmacology , Interleukin-6/pharmacology , Keratinocytes/metabolism , MAP Kinase Signaling System/drug effects , NF-kappa B/metabolism , Phosphorylation/drug effects , Protein Transport/drug effects , Wound Healing , p38 Mitogen-Activated Protein Kinases/metabolism
11.
Article in Korean | WPRIM | ID: wpr-150516

ABSTRACT

PURPOSE: The purpose of this study was to examine the effects of Cu/Zn SOD on reduction of hindlimb muscular atrophy induced by cisplatin in rats. METHODS: Forty-two rats were assigned to three groups; control group, Cisplatin (CDDP) group and cisplatin with Cu/Zn SOD (CDDP-SOD) group. At day 35 hindlimb muscles were dissected. Food intake, activity, withdrawal threshold, muscle weight, and Type I, II fiber cross-sectional area (CSA) of dissected muscles were measured. Relative SOD activity and expression of MHC and phosphorylated Akt, ERK were measured after dissection. RESULTS: Muscle weight and Type I, II fiber CSA of hindlimb muscles in the CDDP group were significantly less than the control group. Muscle weight and Type I, II fiber CSA of hindlimb muscles, food intake, activity, and withdrawal thresholds of the CDDP-SOD group were significantly greater than the CDDP group. There were no significant differences in relative SOD activities of hindlimb muscles between the CDDP-SOD and CDDP groups. MHC expression and phosphorylated Akt, ERK of hindlimb muscles in the CDDP-SOD group were significantly greater than the CDDP group. CONCLUSION: Cu/Zn SOD attenuates hindlimb muscular atrophy induced by cisplatin through increased food intake and activity. Increment of phosphorylated Akt, ERK may relate to attenuation of hindlimb muscular atrophy.


Subject(s)
Animals , Body Weight/drug effects , Cisplatin/toxicity , Disease Models, Animal , Extracellular Signal-Regulated MAP Kinases/metabolism , Hindlimb , Male , Muscle, Skeletal/drug effects , Muscular Atrophy/chemically induced , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Recombinant Proteins/biosynthesis , Superoxide Dismutase/genetics , Superoxides/metabolism
12.
Article in English | WPRIM | ID: wpr-199829

ABSTRACT

Activated protein C (APC) is a cytoprotective anticoagulant that can promote cutaneous healing. We examined the effect of APC on viability and differentiation of the osteoblastic line, MG63, in the presence and absence of bisphosphonates (BPs). Osteoblasts were cultured and treated for 24 or 48 h with Alendronate (Aln), Zoledronate (Zol) or Pamidronate (Pam) at concentrations ranging from 10-4 to 10-6 M. Cell differentiation was measured using type 1 collagen production, Alizarin red staining and alkaline phosphatase activity, whereas cell viability was assessed using MTT and crystal violet assays. All three BPs induced MG63 cell death in a dose- and time-dependent manner. Pam- and Zol-related cell death was prevented by APC treatment; however, cell death induced by Aln was accelerated by APC. APC induced MG63 cell differentiation that was enhanced by Aln, but inhibited by Pam or Zol. Endothelial protein C receptor (EPCR) was expressed by MG63 cells and mediated the protective effect of APC on Zol-induced viability. In summary, we have demonstrated that (1) APC favorably regulates MG63 viability and differentiation toward bone growth, (2) APC differentially regulates the effects of specific BPs and (3) at least part of the effects of APC is mediated through EPCR. These findings highlight the potential importance of the PC pathway in bone physiology and provide strong evidence that APC may influence bone cells and has potential to be a therapeutic drug for bone regeneration, depending on concurrent BP treatment.


Subject(s)
Antigens, CD/metabolism , Caspases/metabolism , Cell Differentiation/drug effects , Cell Survival/drug effects , Collagen Type I/metabolism , Diphosphonates/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Matrix Metalloproteinase 2/metabolism , NF-kappa B/metabolism , Osteoblasts/cytology , Protein C/pharmacology , Receptors, Cell Surface/metabolism , Up-Regulation/drug effects
13.
Article in English | WPRIM | ID: wpr-119450

ABSTRACT

Wnt5a is a ligand that activates the noncanonical Wnt signaling pathways (beta-catenin-independent pathways). Human neutrophils expressed several Wnt5a receptors, such as Frizzled 2, 5 and 8. Stimulation of human neutrophils with Wnt5a caused chemotactic migration and the production of two important chemokines, CXCL8 and CCL2. CCL2 production by Wnt5a was mediated by a pertussis toxin-sensitive G-protein-dependent pathway. Wnt5a also stimulated the phosphorylation of three mitogen-activated protein kinases (MAPKs: ERK, p38 MAPK and JNK) and Akt. Inhibition of ERK, p38 MAPK or JNK by specific inhibitors induced a dramatic reduction in Wnt5a-induced CCL2 production. Supernatant collected from lipopolysaccharide-stimulated macrophages induced neutrophil chemotaxis, which was significantly inhibited by anti-Wnt5a antibody. Our results suggested that Wnt5a may contribute to neutrophil recruitment, mediating the inflammation response.


Subject(s)
Activating Transcription Factor 2/metabolism , Animals , Cell Separation , Chemokines/biosynthesis , Chemotaxis/drug effects , Culture Media, Conditioned/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , GTP-Binding Proteins/metabolism , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Mice , NF-kappa B/metabolism , Neutrophils/cytology , Pertussis Toxin/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Receptors, Wnt/metabolism , Type C Phospholipases/metabolism , Wnt Proteins/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism
14.
Article in English | WPRIM | ID: wpr-35843

ABSTRACT

Radiation and drug resistance remain the major challenges and causes of mortality in the treatment of locally advanced, recurrent and metastatic breast cancer. Dysregulation of phospholipase D (PLD) has been found in several human cancers and is associated with resistance to anticancer drugs. In the present study, we evaluated the effects of PLD inhibition on cell survival, cell death and DNA damage after exposure to ionizing radiation (IR). Combined IR treatment and PLD inhibition led to an increase in the radiation-induced apoptosis of MDA-MB-231 metastatic breast cancer cells. The selective inhibition of PLD1 and PLD2 led to a significant decrease in the IR-induced colony formation of breast cancer cells. Moreover, PLD inhibition suppressed the radiation-induced activation of extracellular signal-regulated kinase and enhanced the radiation-stimulated phosphorylation of the mitogen-activated protein kinases p38 and c-Jun N-terminal kinase. Furthermore, PLD inhibition, in combination with radiation, was very effective at inducing DNA damage, when compared with radiation alone. Taken together, these results suggest that PLD may be a useful target molecule for the enhancement of the radiotherapy effect.


Subject(s)
Breast Neoplasms/drug therapy , Cell Death/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , DNA Damage , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Phospholipase D/antagonists & inhibitors , Radiation Tolerance/drug effects , Radiation, Ionizing , p38 Mitogen-Activated Protein Kinases/metabolism
15.
Braz. j. med. biol. res ; 44(7): 618-623, July 2011. ilus
Article in English | LILACS | ID: lil-595709

ABSTRACT

Taurine has positive effects on bone metabolism. However, the effects of taurine on osteoblast apoptosis in vitro have not been reported. The aim of this study was to investigate the activity of taurine on apoptosis of mouse osteoblastic MC3T3-E1 cells. The data showed that 1, 5, 10, or 20 mM taurine resulted in 16.7, 34.2, 66.9, or 63.75 percent reduction of MC3T3-E1 cell apoptosis induced by the serum deprivation (serum-free α-MEM), respectively. Taurine (1, 5, or 10 mM) also reduced cytochrome c release and inhibited activation of caspase-3 and -9, which were measured using fluorogenic substrates for caspase-3/caspase-9, in serum-deprived MC3T3-E1 cells. Furthermore, taurine (10 mM) induced extracellular signal-regulated kinase (ERK) phosphorylation in MC3T3-E1 cells. Knockdown of the taurine transporter (TAUT) or treatment with the ERK-specific inhibitor PD98059 (10 μM) blocked the activation of ERK induced by taurine (10 mM) and abolished the anti-apoptotic effect of taurine (10 mM) in MC3T3-E1 cells. The present results demonstrate for the first time that taurine inhibits serum deprivation-induced osteoblast apoptosis via the TAUT/ERK signaling pathway.


Subject(s)
Animals , Cattle , Mice , Apoptosis/drug effects , Apoptosis/physiology , Extracellular Signal-Regulated MAP Kinases/metabolism , Membrane Glycoproteins/metabolism , Membrane Transport Proteins/metabolism , Osteoblasts/drug effects , Taurine/pharmacology , Analysis of Variance , Caspase 9/metabolism , /metabolism , Osteoblasts/metabolism , RNA, Messenger/metabolism
16.
Article in English | WPRIM | ID: wpr-123288

ABSTRACT

Hepatitis B virus X (HBx) protein has been known to play an important role in development of hepatocellular carcinoma (HCC). The aim of this study is to find out whether HBx protein expression affects antiproliferative effect of an epidermal growth factor receptor-tyrosine kinase (EGFR-TK) inhibitor and a MEK inhibitor in HepG2 and Huh-7 cell lines. We established HepG2 and Huh-7 cells transfected stably with HBx gene. HBx protein expression increased pERK and pAkt expression as well as beta-catenin activity in both cells. Gefitinib (EGFR-TK inhibitor) inhibited pERK and pAkt expression and beta-catenin activity in both cells. Selumetinib (MEK inhibitor) reduced pERK level and beta-catenin activity but pAkt expression was rather elevated by selumetinib in these cells. Reduction of pERK levels was much stronger with selumetinib than gefitinib in both cells. The antiproliferative efficacy of selumetinib was more potent than that of gefitinib. However, the antiproliferative effect of gefitinib, as well as selumetinib, was not different between cell lines with or without HBx expression. Signal pathway activation by HBx might not be strong enough to attenuate the antiproliferative effect of EGFR-TK inhibitor. Future experiments are needed to understand the role of HBx protein expression in HCC treatment using molecular targeting agent.


Subject(s)
Animals , Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacology , Carcinoma, Hepatocellular/metabolism , Cell Line, Tumor/drug effects , Cell Proliferation , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Liver Neoplasms/metabolism , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt , Quinazolines/pharmacology , ErbB Receptors/antagonists & inhibitors , Signal Transduction/drug effects , Trans-Activators/metabolism , beta Catenin/metabolism
17.
Article in English | WPRIM | ID: wpr-166507

ABSTRACT

PURPOSE: The purpose of this study was to determine the effect of dehydroepiandrosterone (DHEA) on recovery of muscle atrophy induced by Parkinson's disease. METHODS: The rat model was established by direct injection of 6-hydroxydopamine (6-OHDA, 20 microg) into the left striatum using stereotaxic surgery. Rats were divided into two groups; the Parkinson's disease group with vehicle treatment (Vehicle; n=12) or DHEA treatment group (DHEA; n=22). DHEA or vehicle was administrated intraperitoneally daily at a dose of 0.34 mmol/kg for 21 days. At 22-days after DHEA treatment, soleus, plantaris, and striatum were dissected. RESULTS: The DHEA group showed significant increase (p<.01) in the number of tyrosine hydroxylase (TH) positive neurons in the lesioned side substantia nigra compared to the vehicle group. Weights and Type I fiber cross-sectional areas of the contralateral soleus of the DHEA group were significantly greater than those of the vehicle group (p=.02, p=.00). Moreover, extracellular signal-regulated kinase (ERK) phosphorylation significantly decreased in the lesioned striatum, but was recovered with DHEA and also in the contralateral soleus muscle, Akt and ERK phosphorylation recovered significantly and the expression level of myosin heavy chain also recovered by DHEA treatment. CONCLUSION: Our results suggest that DHEA treatment recovers Parkinson's disease induced contralateral soleus muscle atrophy through Akt and ERK phosphorylation.


Subject(s)
Animals , Corpus Striatum/drug effects , Dehydroepiandrosterone/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Male , Muscle Fibers, Slow-Twitch/drug effects , Muscle, Skeletal/drug effects , Muscular Atrophy/drug therapy , Myosins/metabolism , Neurons/drug effects , Oxidopamine/toxicity , Parkinson Disease, Secondary/chemically induced , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Tyrosine 3-Monooxygenase/metabolism
18.
Yonsei Medical Journal ; : 165-172, 2011.
Article in English | WPRIM | ID: wpr-136373

ABSTRACT

PURPOSE: Imbalances between osteogenic and adipogenic differentiation leads to diseases such as osteoporosis. The aim of our study was to demonstrate the differences in extracellular signal-regulated kinase (ERK) phosphorylation during both adipogenesis and osteogenesis of human bone marrow-derived stem cells (BMSCs). MATERIALS AND METHODS: Using troglitazone, GW9662 and U0126, we investigated their role in hBMSC differentiation to adipogenic and osteogenic fates. RESULTS: ERK1/2 inhibition by U0126 suppressed proliferator-activated receptor (PPAR)gamma expression and lipid accumulation, while it decreased the mRNA expression of adipogenic genes (lipoprotein lipase, PPARgamma, and adipocyte protein) and osteogenic genes (type I collagen and osteopontin). ERK phosphorylation was transient and decreased during adipogenesis, whereas it occurred steadily during osteogenesis. Troglitazone, a PPARgamma agonist, induced adipogenesis by inhibiting ERK phosphorylation even in an osteogenic medium, suggesting that ERK signaling needs to be shut off in order to proceed with adipose cell commitment. Cell proliferation was greatly increased in osteogenesis but was not changed during adipogenesis, indicating that ERK might play different roles in cellular proliferation and differentiation between the two committed cell types. CONCLUSION: The duration and magnitude of ERK activation might be a crucial factor for the balance between adipogenesis and osteogenesis in human bone marrow-derived stem cells.


Subject(s)
Adipogenesis/drug effects , Adult , Anilides/pharmacology , Bone Marrow Cells/cytology , Butadienes/pharmacology , Cell Differentiation/drug effects , Cells, Cultured , Chromans/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Humans , Male , Middle Aged , Nitriles/pharmacology , Osteogenesis/drug effects , PPAR gamma/agonists , Phosphorylation/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Stem Cells/cytology , Thiazolidinediones/pharmacology
19.
Yonsei Medical Journal ; : 165-172, 2011.
Article in English | WPRIM | ID: wpr-136372

ABSTRACT

PURPOSE: Imbalances between osteogenic and adipogenic differentiation leads to diseases such as osteoporosis. The aim of our study was to demonstrate the differences in extracellular signal-regulated kinase (ERK) phosphorylation during both adipogenesis and osteogenesis of human bone marrow-derived stem cells (BMSCs). MATERIALS AND METHODS: Using troglitazone, GW9662 and U0126, we investigated their role in hBMSC differentiation to adipogenic and osteogenic fates. RESULTS: ERK1/2 inhibition by U0126 suppressed proliferator-activated receptor (PPAR)gamma expression and lipid accumulation, while it decreased the mRNA expression of adipogenic genes (lipoprotein lipase, PPARgamma, and adipocyte protein) and osteogenic genes (type I collagen and osteopontin). ERK phosphorylation was transient and decreased during adipogenesis, whereas it occurred steadily during osteogenesis. Troglitazone, a PPARgamma agonist, induced adipogenesis by inhibiting ERK phosphorylation even in an osteogenic medium, suggesting that ERK signaling needs to be shut off in order to proceed with adipose cell commitment. Cell proliferation was greatly increased in osteogenesis but was not changed during adipogenesis, indicating that ERK might play different roles in cellular proliferation and differentiation between the two committed cell types. CONCLUSION: The duration and magnitude of ERK activation might be a crucial factor for the balance between adipogenesis and osteogenesis in human bone marrow-derived stem cells.


Subject(s)
Adipogenesis/drug effects , Adult , Anilides/pharmacology , Bone Marrow Cells/cytology , Butadienes/pharmacology , Cell Differentiation/drug effects , Cells, Cultured , Chromans/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Humans , Male , Middle Aged , Nitriles/pharmacology , Osteogenesis/drug effects , PPAR gamma/agonists , Phosphorylation/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Stem Cells/cytology , Thiazolidinediones/pharmacology
20.
Article in English | WPRIM | ID: wpr-73120

ABSTRACT

Recent evidence supports a neuroprotective role of Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) against ischemic brain injury. However, the molecular mechanisms of SHP-2 activation and those governing how SHP-2 exerts its function under oxidative stress conditions are not well understood. Recently we have reported that reactive oxygen species (ROS)-mediated oxidative stress promotes the phosphorylation of endogenous SHP-2 through lipid rafts, and that this phosphorylation strongly occurs in astrocytes, but not in microglia. To investigate the molecules involved in events leading to phosphorylation of SHP-2, raft proteins were analyzed using astrocytes and microglia. Interestingly, caveolin-1 and -2 were detected only in astrocytes but not in microglia, whereas flotillin-1 was expressed in both cell types. To examine whether the H2O2-dependent phosphorylation of SHP-2 is mediated by caveolin-1, we used specific small interfering RNA (siRNA) to downregulate caveolin-1 expression. In the presence of caveolin-1 siRNA, the level of SHP-2 phosphorylation induced by H2O2 was significantly decreased, compared with in the presence of control siRNA. Overexpression of caveolin-1 effectively increased H2O2-induced SHP-2 phosphorylation in microglia. Lastly, H2O2 induced extracellular signal-regulated kinase (ERK) activation in astrocytes through caveolin-1. Our results suggest that caveolin-1 is involved in astrocyte-specific intracellular responses linked to the SHP-2-mediated signaling cascade following ROS-induced oxidative stress.


Subject(s)
Animals , Astrocytes/metabolism , Caveolin 1/genetics , Caveolin 2/genetics , Cell Line , Cells, Cultured , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression , Humans , Microglia/metabolism , Phosphoric Monoester Hydrolases/metabolism , Phosphorylation , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Rats , Reactive Oxygen Species/metabolism
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