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1.
Int J Mol Sci ; 24(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37834290

RESUMO

The differentiation and function of osteocytes are controlled by surrounding cells and mechanical stress; however, the detailed mechanisms are unknown. Recent findings suggest that IL-33 is highly expressed in periodontal tissues in orthodontic tooth movement. The present study aimed to elucidate the effect of IL-33 on the expression of regulatory factors for bone remodeling and their molecular mechanisms in the osteocyte-like cell line MLO-Y4. MLO-Y4 cells were treated with IL-33, and the activation of intracellular signaling molecules and transcriptional factors was determined using Western blot analysis and chromatin immunoprecipitation assay. IL-33 treatment enhanced the expression of IL-6 in MLO-Y4 cells, which was suppressed by the knockdown of the IL-33 receptor ST2L. Additionally, IL-33 treatment induced activation of NF-κB, JNK/AP-1, and p38 MAPK signaling pathways in MLO-Y4 cells. Moreover, pretreatment with specific inhibitors of NF-κB, p38 MAPK, and JNK/AP-1 attenuated the IL-33-induced expression of IL-6. Furthermore, chromatin immunoprecipitation indicated that IL-33 increased c-Jun recruitment to the IL-6 promoter. Overall, these results suggest that IL-33 induces IL-6 expression and regulates osteocyte function via activation of the NF-κB, JNK/AP-1, and p38 MAPK pathways through interaction with ST2L receptors on the plasma membrane.


Assuntos
Interleucina-6 , NF-kappa B , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Interleucina-33/farmacologia , Interleucina-33/metabolismo , Fator de Transcrição AP-1/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Osteócitos/metabolismo
2.
J Proteome Res ; 20(7): 3519-3531, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34115501

RESUMO

Extracellular vesicles (EVs) are biomarkers and mediators of intercellular communication. In biological samples, EVs are secreted by various types of cells. The proteomic identification of proteins expressed in EVs has potential to contribute to research and clinical applications, particularly for cancer. In this study, the proximity-labeling method-based proteomic approach was used for EV identification, labeling membrane components proximal to a given molecule on the EV membrane surface. Due to the small labeling range, proteins on the surface of the same EVs are likely to be labeled by selecting a given EV surface antigen. The protein group of cancer cell-secreted EV (cEV), which abundantly expresses a close homologue of L1 (CHL1), was examined using a model mouse for lung cancer (LC). cEV-expressed proteins were identified by proteomic analysis of enzyme-mediated activation of radical sources by comparing serum EVs from wild-type and LC mice. SLC4A1 was found to be co-expressed in CHL1-expressing EVs, highlighting EVs expressing both CHL1 and SLC4A1 as candidates for cEVs. Serum EVs expressing both CHL1 and caspase 14 were significantly elevated in LC patients compared with healthy individuals. Thus, the combination of proximity labeling and proteomic analysis allows for effective EV identification.


Assuntos
Vesículas Extracelulares , Proteômica , Animais , Proteína 1 de Troca de Ânion do Eritrócito , Biomarcadores , Moléculas de Adesão Celular , Humanos , Camundongos , Proteínas
3.
BMC Biol ; 18(1): 75, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600317

RESUMO

BACKGROUND: Lymphocytes circulate between peripheral lymphoid tissues via blood and lymphatic systems, and chemokine-induced migration is important in trafficking lymphocytes to distant sites. The small GTPase Rap1 is important in mediating lymphocyte motility, and Rap1-GEFs are involved in chemokine-mediated Rap1 activation. Here, we describe the roles and mechanisms of Rap1-GEFs in lymphocyte trafficking. RESULTS: In this study, we show that RA-GEF-1 and 2 (also known as Rapgef2 and 6) are key guanine nucleotide exchange factors (GEF) for Rap1 in lymphocyte trafficking. Mice harboring T cell-specific knockouts of Rapgef2/6 demonstrate defective homing and egress of T cells. Sphingosine-1-phosphate (S1P) as well as chemokines activates Rap1 in a RA-GEF-1/2-dependent manner, and their deficiency in T cells impairs Mst1 phosphorylation, cell polarization, and chemotaxis toward S1P gradient. On the other hand, B cell-specific knockouts of Rapgef2/6 impair chemokine-dependent retention of B cells in the bone marrow and passively facilitate egress. Phospholipase D2-dependent production of phosphatidic acid by these chemotactic factors determines spatial distribution of Rap1-GTP subsequent to membrane localization of RA-GEFs and induces the development of front membrane. On the other hand, basal de-phosphorylation of RA-GEFs is necessary for chemotactic factor-dependent increase in GEF activity for Rap1. CONCLUSIONS: We demonstrate here that subcellular distribution and activation of RA-GEFs are key factors for a directional movement of lymphocytes and that phosphatidic acid is critical for membrane translocation of RA-GEFs with chemokine stimulation.


Assuntos
Movimento Celular , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Linfócitos/fisiologia , Ácidos Fosfatídicos/metabolismo , Animais , Linhagem Celular , Feminino , Humanos , Masculino , Camundongos , Fosforilação
4.
Reprod Med Biol ; 19(4): 378-384, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33071640

RESUMO

PURPOSE: Subendometrial myometrium exerts wave-like activity throughout the menstrual cycle, and uterine peristalsis is markedly reduced during the implantation phase. We hypothesized that abnormal uterine peristalsis has an adverse effect on the endometrial decidualization process. We conducted an in vitro culture experiment to investigate the effect of cyclic stretch on the morphological and biological endometrial decidual process. METHODS: Primary human endometrial stromal cells (HESCs) were isolated from hysterectomy specimens and incubated with or without 8-bromo-cyclic adenosine monophosphate (8-br-cAMP) and medroxyprogesterone acetate (MPA) for 3 days. After decidualization, cultures were continued for 24 hours with or without cyclic stretch using a computer-operated cell tension system. RESULTS: Cyclic stretch significantly repressed expression of decidual markers including insulin-like growth factor-binding protein 1 (IGFBP1), prolactin (PRL), forkhead box O1 (FOXO1), and WNT4 on decidualized HESCs. In addition, cyclic stretch of decidualized HESCs affected the decidual morphological phenotype to an elongated shape. The alternation of F-actin localization in decidualized HESCs was not observed in response to cyclic stretch. CONCLUSIONS: These data suggest that cyclic stretch inhibits the morphological and biological decidual process of HESCs. Our findings imply that uterine abnormal contractions during the implantation period impair endometrial decidualization and contribute to infertility.

5.
Nature ; 497(7450): 490-3, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23644455

RESUMO

Semaphorin 3A (Sema3A) is a diffusible axonal chemorepellent that has an important role in axon guidance. Previous studies have demonstrated that Sema3a(-/-) mice have multiple developmental defects due to abnormal neuronal innervations. Here we show in mice that Sema3A is abundantly expressed in bone, and cell-based assays showed that Sema3A affected osteoblast differentiation in a cell-autonomous fashion. Accordingly, Sema3a(-/-) mice had a low bone mass due to decreased bone formation. However, osteoblast-specific Sema3A-deficient mice (Sema3acol1(-/-) and Sema3aosx(-/-) mice) had normal bone mass, even though the expression of Sema3A in bone was substantially decreased. In contrast, mice lacking Sema3A in neurons (Sema3asynapsin(-/-) and Sema3anestin(-/-) mice) had low bone mass, similar to Sema3a(-/-) mice, indicating that neuron-derived Sema3A is responsible for the observed bone abnormalities independent of the local effect of Sema3A in bone. Indeed, the number of sensory innervations of trabecular bone was significantly decreased in Sema3asynapsin(-/-) mice, whereas sympathetic innervations of trabecular bone were unchanged. Moreover, ablating sensory nerves decreased bone mass in wild-type mice, whereas it did not reduce the low bone mass in Sema3anestin(-/-) mice further, supporting the essential role of the sensory nervous system in normal bone homeostasis. Finally, neuronal abnormalities in Sema3a(-/-) mice, such as olfactory development, were identified in Sema3asynasin(-/-) mice, demonstrating that neuron-derived Sema3A contributes to the abnormal neural development seen in Sema3a(-/-) mice, and indicating that Sema3A produced in neurons regulates neural development in an autocrine manner. This study demonstrates that Sema3A regulates bone remodelling indirectly by modulating sensory nerve development, but not directly by acting on osteoblasts.


Assuntos
Remodelação Óssea , Osso e Ossos/inervação , Osso e Ossos/metabolismo , Semaforina-3A/metabolismo , Células Receptoras Sensoriais/metabolismo , Animais , Osso e Ossos/anatomia & histologia , Diferenciação Celular , Células Cultivadas , Feminino , Masculino , Camundongos , Tamanho do Órgão , Osteoblastos/citologia , Osteoblastos/metabolismo , Semaforina-3A/deficiência , Semaforina-3A/genética , Células Receptoras Sensoriais/citologia
6.
BMC Musculoskelet Disord ; 20(1): 327, 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31299959

RESUMO

BACKGROUND: This study was conducted to determine gender differences in the relationship between extracurricular sports activities (ECSA) and low back pain (LBP) in children and adolescents. METHODS: In a cohort analysis of a 6-year birth cohort annual survey, students were followed from the fourth to sixth grades of elementary school (E4-E6; 9-12 years old) through the first to third grades of junior high school (J1-J3; 12-15 years old). All students completed annual questionnaires on ECSA and LBP. The odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the association strength between ECSA and LBP. We also calculated the population attributable fraction (PAF), which was defined as the proportion of students with ECSA-related LBP among all students with LBP. RESULTS: ECSA was significantly associated with LBP only in grade J3 among boys (OR: 2.00, 95% CI: 1.47-2.71). On the other hand, among girls, ECSA was significantly associated with LBP in grades E5 (OR: 1.48, 95% CI: 1.00-2.20), E6 (OR: 1.91, 95% CI: 1.33-2.75), and J3 (OR: 1.81, 95% CI: 1.26-2.61). Among boys, PAF was similar in all grades (range, 10-16%), whereas among girls, the PAF varied (- 11 to 29%) and was significantly higher in girls than in boys in grades E5 (19.0% vs. 1.1%, P < 0.01) and E6 (28.8% vs. 12.8%, P < 0.01). CONCLUSIONS: Although there was a link between ECSA and LBP in both boys and girls, girls were more susceptible to ECSA-related LBP, especially in grades E5 and E6.


Assuntos
Dor Lombar/epidemiologia , Esportes/estatística & dados numéricos , Adolescente , Criança , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Dor Lombar/etiologia , Masculino , Prevalência , Fatores de Risco , Fatores Sexuais , Estudantes/estatística & dados numéricos , Inquéritos e Questionários/estatística & dados numéricos
7.
J Biol Chem ; 292(31): 12885-12894, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28607151

RESUMO

Satellite cells are skeletal muscle stem cells that provide myonuclei for postnatal muscle growth, maintenance, and repair/regeneration in adults. Normally, satellite cells are mitotically quiescent, but they are activated in response to muscle injury, in which case they proliferate extensively and exhibit up-regulated expression of the transcription factor MyoD, a master regulator of myogenesis. MyoD forms a heterodimer with E proteins through their basic helix-loop-helix domain, binds to E boxes in the genome and thereby activates transcription at muscle-specific promoters. The central role of MyoD in muscle differentiation has increased interest in finding potential MyoD regulators. Here we identified transducin-like enhancer of split (TLE3), one of the Groucho/TLE family members, as a regulator of MyoD function during myogenesis. TLE3 was expressed in activated and proliferative satellite cells in which increased TLE3 levels suppressed myogenic differentiation, and, conversely, reduced TLE3 levels promoted myogenesis with a concomitant increase in proliferation. We found that, via its glutamine- and serine/proline-rich domains, TLE3 interferes with MyoD function by disrupting the association between the basic helix-loop-helix domain of MyoD and E proteins. Our findings indicate that TLE3 participates in skeletal muscle homeostasis by dampening satellite cell differentiation via repression of MyoD transcriptional activity.


Assuntos
Proteínas Correpressoras/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Muscular , Fibras Musculares Esqueléticas/metabolismo , Proteína MyoD/antagonistas & inibidores , Mioblastos/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Fator 3 Ativador da Transcrição/química , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Animais , Proliferação de Células , Células Cultivadas , Proteínas Correpressoras/antagonistas & inibidores , Proteínas Correpressoras/química , Proteínas Correpressoras/genética , Deleção de Genes , Sequências Hélice-Alça-Hélice , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/citologia , Proteína MyoD/química , Proteína MyoD/genética , Proteína MyoD/metabolismo , Mioblastos/citologia , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Interferência de RNA , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Células Satélites de Músculo Esquelético/citologia
8.
Molecules ; 22(3)2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28294983

RESUMO

The special sense of taste guides and guards food intake and is essential for body maintenance. Salty and sour tastes are sensed via ion channels or gated ion channels while G protein-coupled receptors (GPCRs) of the taste receptor type 1 (T1R) family sense sweet and umami tastes and GPCRs of the taste receptor type 2 (T2R) family sense bitter tastes. T1R and T2R receptors share similar downstream signaling pathways that result in the stimulation of phospholipase-C-ß2. The T1R family includes three members that form heterodimeric complexes to recognize either amino acids or sweet molecules such as glucose. Although these functions were originally described in gustatory tissue, T1R family members are expressed in numerous non-gustatory tissues and are now viewed as nutrient sensors that play important roles in monitoring global glucose and amino acid status. Here, we highlight emerging evidence detailing the function of T1R family members in the musculoskeletal system and review these findings in the context of the musculoskeletal diseases sarcopenia and osteoporosis, which are major public health problems among the elderly that affect locomotion, activities of daily living, and quality of life. These studies raise the possibility that T1R family member function may be modulated for therapeutic benefit.


Assuntos
Remodelação Óssea , Fenômenos Fisiológicos Musculoesqueléticos , Receptores Acoplados a Proteínas G/metabolismo , Aminoácidos/metabolismo , Animais , Glucose/metabolismo , Humanos , Osteoporose/genética , Receptores Acoplados a Proteínas G/genética , Sarcopenia/genética , Transdução de Sinais
9.
Cytokine ; 83: 1-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26999703

RESUMO

The nitrogen-containing bisphosphonate (BP) zoledronic acid (ZA) is a potent antiresorptive drug used in conjunction with standard cancer therapy to treat osteolysis or hypercalcemia due to malignancy. However, it is unclear how ZA influences the circulating levels of bone remodeling factors. The aim of this study was to evaluate the effects of ZA on the serum levels of soluble receptor activator of NF-kB ligand (sRANKL) and osteoprotegerin (OPG). The following four groups of C57BL/6 mice were used (five mice per group): (1) the placebo+phosphate-buffered saline (PBS) group, in which placebo-treated mice were injected once weekly with PBS for 4weeks; (2) the placebo+ZA group, in which placebo-treated mice were injected once weekly with ZA for 4weeks; (3) the prednisolone (PSL)+PBS group, in which PSL-treated mice were injected once weekly with PBS for 4weeks; and (4) the PSL+ZA group, in which PSL-treated mice were injected once weekly with ZA for 4weeks. At the 3-week time point, all mice were subjected to oral inflammatory stimulation with bacterial lipopolysaccharide (LPS). The sera of these mice were obtained every week and the levels of sRANKL and OPG were measured using enzyme-linked immunosorbent assay. At the time of sacrifice, femurs were prepared for micro-computed tomography (micro-CT), histological, and histomorphometric analyses. Our data indicated that ZA administration remarkably reduced bone turnover and significantly increased the basal level of sRANKL. Interestingly, the PSL+ZA group showed a dramatically elevated sRANKL level after LPS stimulation. In contrast, the PSL+ZA group in nonobese diabetic mice with severe combined immunodeficiency disease (NOD-SCID mice), which are characterized by the absence of functional T- and B-lymphocytes, showed no increase in the sRANKL level. Our data suggest that, particularly with combination treatment of ZA and glucocorticoids, surviving lymphocytes might be the source of inflammation-induced sRANKL. Thus, circulating sRANKL levels might be modulated by ZA.


Assuntos
Linfócitos B/metabolismo , Difosfonatos/farmacologia , Glucocorticoides/farmacologia , Imidazóis/farmacologia , Lipopolissacarídeos/toxicidade , Ligante RANK/sangue , Linfócitos T/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Osteoprotegerina/sangue , Ácido Zoledrônico
10.
J Orthop Sci ; 21(3): 282-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27021250

RESUMO

PURPOSE: To elucidate clinico-radiological features, therapeutic outcomes, and survival factors of vertebral osteomyelitis patients infected by methicillin-resistant staphylococci (MRS). METHODS: Vertebral osteomyelitis patients admitted to the orthopaedic department between 2007 and 2011 (n = 248) were selected for this multicenter study. We compared patients' backgrounds, therapeutic course, and in-hospital mortality between MRS and methicillin-susceptible staphylococci (MSS). We also examined survival factors of vertebral osteomyelitis due to MRS. RESULTS: Sixteen patients of MRS vertebral osteomyelitis and 55 patients of MSS were included in this study. In MRS vertebral osteomyelitis, the rates of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and operation of surgical debridement were higher compared to those in MSS vertebral osteomyelitis. Univariate analysis showed that operation of surgical debridement was a factor related to survival in MRS patients. CONCLUSIONS: Higher rate of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and performing surgical debridement are peculiar features of MRS vertebral osteomyelitis compared to MSS vertebral osteomyelitis. If patients with MRS vertebral osteomyelitis respond poorly to antibiotic therapy, it might be better to consider surgical debridement not to lose an opportunity of operation due to exacerbation of systemic conditions.


Assuntos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Osteomielite/microbiologia , Osteomielite/mortalidade , Espondilite/microbiologia , Espondilite/mortalidade , Infecções Estafilocócicas/mortalidade , Adulto , Idoso , Antibacterianos/uso terapêutico , Causas de Morte , Bases de Dados Factuais , Desbridamento/métodos , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Japão , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Osteomielite/diagnóstico , Osteomielite/terapia , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/microbiologia , Espondilite/diagnóstico por imagem , Espondilite/terapia , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/terapia , Estatísticas não Paramétricas , Análise de Sobrevida
11.
Clin Calcium ; 26(8): 1127-34, 2016 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-27461495

RESUMO

Bone tissues including bone marrow are comprised of various cells. A growing body of evidence suggests that nerve cells which exist in and around bone such as periosteal and bone marrow build a close relationship with bone cells. Namely, it was revealed that central nervous system governs bone tissues via peripheral nervous system and neurotransmitters or cytokines play a role for the communication between bone and nerve in the last decade. In this paper, I would like to review "osteo-neural" related factors which has been well-documented so far.


Assuntos
Osso e Ossos/metabolismo , Sistema Nervoso Central/metabolismo , Homeostase , Animais , Citocinas/metabolismo , Humanos , Neurotransmissores/metabolismo
12.
Biochem Biophys Res Commun ; 468(4): 568-73, 2015 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-26545778

RESUMO

T1R3 is a T1R class of G protein-coupled receptors, composing subunit of the umami taste receptor when complexed with T1R1. T1R3 was originally discovered in gustatory tissue but is now known to be expressed in a wide variety of tissues and cell types such the intestine, pancreatic ß-cells, skeletal muscle, and heart. In addition to taste recognition, the T1R1/T1R3 complex functions as an amino acid sensor and has been proposed to be a control mechanism for the secretion of hormones, such as cholecystokinin, insulin, and duodenal HCO3(-) and activates the mammalian rapamycin complex 1 (MTORC1) to inhibit autophagy. T1R3 knockout mice have increased rate of autophagy in the heart, skeletal muscle and liver. Thus, T1R3 has multiple physiological functions and is widely expressed in vivo. However, the exact mechanisms regulating T1R3 expression are largely unknown. Here, we used comparative genomics and functional analyses to characterize the genomic region upstream of the annotated transcriptional start of human T1R3. This revealed that the T1R3 promoter in human and mouse resides in an evolutionary conserved region (ECR). We also identified a repressive element located upstream of the human T1R3 promoter that has relatively high degree of conservation with rhesus macaque. Additionally, the muscle regulatory factors MyoD and Myogenin regulate T1R3 expression and T1R3 expression increases with skeletal muscle differentiation of murine myoblast C2C12 cells. Taken together, our study raises the possibility that MyoD and Myogenin might control skeletal muscle metabolism and homeostasis through the regulation of T1R3 promoter activity.


Assuntos
Mioblastos/metabolismo , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Animais , Sequência de Bases , Sequência Conservada , Regulação da Expressão Gênica/fisiologia , Camundongos , Dados de Sequência Molecular , Especificidade da Espécie
13.
J Clin Biochem Nutr ; 56(1): 1-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25834301

RESUMO

Fridovich identified CuZnSOD in 1969 and manganese superoxide dismutase (MnSOD) in 1973, and proposed "the Superoxide Theory," which postulates that superoxide (O2 (•-)) is the origin of most reactive oxygen species (ROS) and that it undergoes a chain reaction in a cell, playing a central role in the ROS producing system. Increased oxidative stress on an organism causes damage to cells, the smallest constituent unit of an organism, which can lead to the onset of a variety of chronic diseases, such as Alzheimer's, Parkinson's, amyotrophic lateral sclerosis and other neurological diseases caused by abnormalities in biological defenses or increased intracellular reactive oxygen levels. Oxidative stress also plays a role in aging. Antioxidant systems, including non-enzyme low-molecular-weight antioxidants (such as, vitamins A, C and E, polyphenols, glutathione, and coenzyme Q10) and antioxidant enzymes, fight against oxidants in cells. Superoxide is considered to be a major factor in oxidant toxicity, and mitochondrial MnSOD enzymes constitute an essential defense against superoxide. Mitochondria are the major source of superoxide. The reaction of superoxide generated from mitochondria with nitric oxide is faster than SOD catalyzed reaction, and produces peroxynitrite. Thus, based on research conducted after Fridovich's seminal studies, we now propose a modified superoxide theory; i.e., superoxide is the origin of reactive oxygen and nitrogen species (RONS) and, as such, causes various redox related diseases and aging.

15.
J Biol Chem ; 288(43): 31299-312, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-23990468

RESUMO

Osteoclast formation is regulated by balancing between the receptor activator of nuclear factor-κB ligand (RANKL) expressed in osteoblasts and extracellular negative regulatory cytokines such as interferon-γ (IFN-γ) and interferon-ß (IFN-ß), which can suppress excessive bone destruction. However, relatively little is known about intrinsic negative regulatory factors in RANKL-mediated osteoclast differentiation. Here, we show the paired-box homeodomain transcription factor Pax6 acts as a negative regulator of RANKL-mediated osteoclast differentiation. Electrophoretic mobility shift and reporter assays found that Pax6 binds endogenously to the proximal region of the tartrate acid phosphatase (TRAP) gene promoter and suppresses nuclear factor of activated T cells c1 (NFATc1)-induced TRAP gene expression. Introduction of Pax6 retrovirally into bone marrow macrophages attenuates RANKL-induced osteoclast formation. Moreover, we found that the Groucho family member co-repressor Grg6 contributes to Pax6-mediated suppression of the TRAP gene expression induced by NFATc1. These results suggest that Pax6 interferes with RANKL-mediated osteoclast differentiation together with Grg6. Our results demonstrate that the Pax6 pathway constitutes a new aspect of the negative regulatory circuit of RANKL-RANK signaling in osteoclastogenesis and that the augmentation of Pax6 might therefore represent a novel target to block pathological bone resorption.


Assuntos
Fosfatase Ácida/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Proteínas do Olho/metabolismo , Proteínas de Homeodomínio/metabolismo , Isoenzimas/metabolismo , Osteoclastos/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Ligante RANK/metabolismo , Proteínas Repressoras/metabolismo , Elementos de Resposta/fisiologia , Fosfatase Ácida/genética , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Proteínas Correpressoras , Proteínas do Olho/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Proteínas de Homeodomínio/genética , Humanos , Isoenzimas/genética , Camundongos , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/citologia , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/genética , Ligante RANK/genética , Proteínas Repressoras/genética , Fosfatase Ácida Resistente a Tartarato
16.
Biochim Biophys Acta ; 1834(3): 634-41, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23298542

RESUMO

We improved the enzymatic properties of the oxidatively stable alkaline serine protease KP-43 through protein engineering to make it more suitable for use in laundry detergents. To enhance proteolytic activity, the gene encoding KP-43 was mutagenized by error-prone PCR. Screening identified a Tyr195Cys mutant enzyme that exhibited increased specific activity toward casein between pH 7 and 11. At pH 10, the mutant displayed 1.3-fold higher specific activity for casein compared to the wild-type enzyme, but the activity of the mutant was essentially unchanged toward several synthetic peptides. Furthermore, the Tyr195Cys mutation significantly increased thermal stability and surfactant stability of the enzyme under oxidizing conditions. Examination of the crystal structure of KP-43 revealed that Tyr195 is a solvent exposed residue that forms part of a flexible loop that binds a Ca(2+) ion. This residue lies 15-20Å away from the residues comprising the catalytic triad of the enzyme. These results suggest that the substitution at position 195 does not alter the structure of the active center, but instead may affect a substrate-enzyme interaction. We propose that the Tyr195Cys mutation enhances the interaction with Ca(2+) and affects the packing of the Ca(2+) binding loop, consequently increasing protein stability. The simultaneously increased proteolytic activity, thermal stability, and surfactant stability of the Tyr195Cys mutant enzyme make the protein an ideal candidate for laundry detergent application.


Assuntos
Substituição de Aminoácidos , Proteínas de Bactérias/genética , Mutação , Serina Endopeptidases/genética , Álcalis/química , Sequência de Aminoácidos , Bacillus/enzimologia , Bacillus/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação/genética , Cálcio/química , Cálcio/metabolismo , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Estabilidade Enzimática/genética , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Proteólise , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Tensoativos/química , Temperatura , Tirosina/genética , Tirosina/metabolismo
17.
Biochem Biophys Res Commun ; 438(1): 205-10, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23880346

RESUMO

In senile osteoporosis the balance of adipogenesis and osteoblastogenesis in bone marrow stromal cells (BMSCs) is disrupted so that adipogenesis is increased with respect to osteoblastogenesis, and as a result, bone mass is decreased. While the molecular mechanisms controlling the balance between osteoblastogenesis and adipogenesis are of great interest, the exact nature of the signals regulating this process remains to be determined. In general, adipogenesis is a reciprocal relationship with osteoblastogenesis in BMSCs. Recently transducin-like enhancer of split 3 (TLE3), was reported to enhance adipogenesis in pre adipocytes. However, the effect of TLE3 on osteoblast differentiation of BMSCs is completely unknown. Here we report that TLE3 not only enhances adipocyte differentiation in BMSCs but also suppresses osteoblast differentiation. Firstly we examined the expression and localization of TLE3. We found that TLE3 is expressed in the nucleus of bone marrow stromal cells and that over-expression of TLE3 induced adipocyte differentiation and suppressed ALP activity induced by treatment with BMP2 in these cells. In contrast, adipocyte differentiation was decreased and ALP activity increased when endogenous TLE3 was knocked down by shRNA in BMSCs. To examine the mechanism by which TLE3 is able to suppress osteoblast differentiation, we focused on Runx2, a transcription factor essential for osteoblast differentiation. We found that TLE3 strongly suppressed ALP activity and OSE2-luciferase activity induced by Runx2 and this repression of Runx2 by TLE3 occurs via HDACs because treatment with TSA, a class I and II HDAC inhibitor, rescued this repression. In conclusion, we identify TLE3 as a suppressor of BMSC differentiation in osteoblast lineage cells in vitro. Our data suggest that TLE3 activity may be a key in balancing adipocyte and osteoblast differentiation in the adult bone marrow microenvironment.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Proteínas/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Proteínas Correpressoras , Células HEK293 , Humanos , Masculino , Camundongos
18.
J Infect Chemother ; 19(1): 166-70, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22911089

RESUMO

A 65-year-old man was admitted to our hospital with a temperature of 39.3 °C, cough, sputum, and pharyngeal discomfort that had persisted for 3 days. He had been treated with methotrexate and adalimumab (a tumor necrosis factor-alpha [TNF-α] inhibitor) for rheumatoid arthritis for 2 years, and he had also been treated with S-1 (tegafur, gimeracil, and oteracil potassium) for pancreatic metastasis of gastric cancer for 2 months. Regardless of the underlying pathologies, his general condition was good and he had worked as an electrician until 2 days before admission. However, his appetite had suddenly decreased from the day before admission, and high fever and hypoxia were also evident upon admission. A chest X-ray and computed tomography scan revealed left pleural effusion and consolidation in both lungs. The pneumonia severity index score was 165 and the risk class was V. Accordingly, we started to treat the pneumonia with a combination of levofloxacin and meropenem. Thereafter, we received positive urinary antigen test findings for Legionella pneumophila. After hospitalization, hypoxia was progressed and hypotension was emerged. Despite the application of appropriate antibiotics, vasopressors, and oxygenation, the patient died 8 h after admission. Even after his death, blood cultures were continued to consider the possibility of bacterial co-infection. Although no bacteria were detected from blood cultures, Gimenez staining revealed pink bacteria in blood culture fluids. Subsequent blood fluid culture in selective medium revealed L. pneumophila serogroup 1. Recently, TNF-α inhibitors have been described as a risk factor for Legionnaires' disease. In consideration of the increased frequency of TNF-α inhibitors, we may need to recognize anew that L. pneumophila might be a pathogen of severe community-acquired pneumonia.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Artrite Reumatoide/terapia , Legionella pneumophila/isolamento & purificação , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Idoso , Antibacterianos , Técnicas Bacteriológicas , Sangue/microbiologia , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Meios de Cultura , Humanos , Legionella pneumophila/classificação , Legionella pneumophila/efeitos dos fármacos , Doença dos Legionários/diagnóstico , Doença dos Legionários/diagnóstico por imagem , Doença dos Legionários/microbiologia , Pulmão/diagnóstico por imagem , Masculino , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/microbiologia , Radiografia Torácica , Fatores de Risco , Sorotipagem
19.
Gan To Kagaku Ryoho ; 40(9): 1225-8, 2013 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-24047785

RESUMO

A 66-year-old man was admitted to our hospital with a diagnosis of advanced gastric cancer, with a tumor embolus in the portal vein and lymph node metastases. Since curative surgery was deemed impossible, we started neoadjuvant chemotherapy using S-1 plus CDDP. After 1 course of chemotherapy, the embolus in the portal vein disappeared. After additional chemotherapy, the primary tumor and lymph nodes were reduced in size, and a total gastrectomy with splenectomy and lymph node dissection was performed. Although he received S-1 medication as adjuvant chemotherapy, a tumor embolus in the portal vein appeared 8 months after the operation. Chemoradiotherapy(S-1+total of 50.4 Gy)was performed and the tumor embolus disappeared.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Embolia/etiologia , Terapia Neoadjuvante , Veia Porta/patologia , Neoplasias Gástricas/terapia , Idoso , Cisplatino/administração & dosagem , Combinação de Medicamentos , Humanos , Masculino , Ácido Oxônico/administração & dosagem , Neoplasias Gástricas/complicações , Neoplasias Gástricas/patologia , Tegafur/administração & dosagem
20.
J Cataract Refract Surg ; 49(5): 479-484, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36700931

RESUMO

PURPOSE: The aim of this study was to estimate the efficacy of the 8-chop technique in phacoemulsification surgeries of patients with cataract. SETTING: Sato Eye Clinic, Chiba-ken, Japan. DESIGN: Prospective study. METHODS: Patients were classified into 3 groups (Grade II, Grade III, and Grade IV; n = 50 each) according to the firmness of their lens nuclei. The Eight-chopper I was used for Grade II, Eight-chopper II for Grade III, and Lance-chopper for Grade IV. The best-corrected visual acuity, intraocular pressure (IOP), and endothelial cell density were evaluated at 7 and 19 weeks postoperatively. The primary outcome measures were the mean operative time, mean phaco time, cumulative dissipated energy (CDE), and volume of fluid used. RESULTS: 150 cataract surgeries were performed. The operative time (minutes), phaco time (seconds), CDE, and volume of fluid used (milliliters) differed significantly among the 3 groups, increasing in the following order: Grade II, Grade III, and Grade IV ( P < .01). The corneal endothelial cell density did not decrease significantly in the 3 groups at 19 weeks postoperatively ( P = .09). The rate of endothelial cell loss was 0.9% ± 5.9%, 1.0% ± 10.3%, and 5.3% ± 11.1% in the Grade II, III, and IV groups at 19 weeks postoperatively, respectively. There were significant reductions in the IOP at 7 and 19 weeks postoperatively compared with the preoperative IOP in the 3 groups ( P < .01). CONCLUSIONS: The 8-chop technique was effective and safe in phacoemulsification for patients with cataracts with lens nuclei of varying hardness.


Assuntos
Extração de Catarata , Catarata , Facoemulsificação , Humanos , Facoemulsificação/métodos , Endotélio Corneano , Estudos Prospectivos , Extração de Catarata/métodos , Catarata/complicações
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