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1.
Nat Commun ; 14(1): 8502, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38135691

RESUMO

In human celiac disease (CeD) HLA-DQ2.5 presents gluten peptides to antigen-specific CD4+ T cells, thereby instigating immune activation and enteropathy. Targeting HLA-DQ2.5 with neutralizing antibody for treating CeD may be plausible, yet using pan-HLA-DQ antibody risks affecting systemic immunity, while targeting selected gluten peptide:HLA-DQ2.5 complex (pHLA-DQ2.5) may be insufficient. Here we generate a TCR-like, neutralizing antibody (DONQ52) that broadly recognizes more than twenty-five distinct gluten pHLA-DQ2.5 through rabbit immunization with multi-epitope gluten pHLA-DQ2.5 and multidimensional optimization. Structural analyses show that the proline-rich and glutamine-rich motif of gluten epitopes critical for pathogenesis is flexibly recognized by multiple tyrosine residues present in the antibody paratope, implicating the mechanisms for the broad reactivity. In HLA-DQ2.5 transgenic mice, DONQ52 demonstrates favorable pharmacokinetics with high subcutaneous bioavailability, and blocks immunity to gluten while not affecting systemic immunity. Our results thus provide a rationale for clinical testing of DONQ52 in CeD.


Assuntos
Doença Celíaca , Glutens , Camundongos , Animais , Humanos , Coelhos , Glutens/química , Anticorpos Neutralizantes , Antígenos HLA-DQ , Peptídeos/química , Epitopos/química , Camundongos Transgênicos
2.
Sci Rep ; 12(1): 3490, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232985

RESUMO

The mechanisms of oceanic animal migration remain enigmatic. Adult Japanese eels start their long-distance oceanic migration from coastal areas to breed near the West Mariana Ridge. We tracked acoustically tagged eels released in the Kuroshio Current (KC) area near Japan (five silver-phase eels, three of which had impaired swim bladders) and a tropical/subtropical (TS) area near/in the spawning area (two yellow-phase and three silver-phase eels). We analyzed their active swimming and transport by water currents. The strong flow of the KC dominated the eels' movements in the north, and TS area; their swimming influenced their movements. In the KC area, greater distances were covered at night than during the day, because eels swam in shallower layers with strong currents at night. Three and one eel in the TS and KC area in the upper 400 m showed counterclockwise and clockwise movements around the time of solar culmination, respectively. The meta-analysis showed that eels released at middle latitudes (20°-34° N) generally swam southward through currents, whereas those released at low latitudes (12°-13° N) generally swam northward through currents. Our study suggests the influence of the surrounding current and a potential effect of solar cues on the movements of Japanese eels.


Assuntos
Anguilla , Migração Animal , Animais , Oceanos e Mares , Prata , Natação
3.
Cell ; 184(11): 3006-3021.e17, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33930287

RESUMO

Genetic studies have revealed many variant loci that are associated with immune-mediated diseases. To elucidate the disease pathogenesis, it is essential to understand the function of these variants, especially under disease-associated conditions. Here, we performed a large-scale immune cell gene-expression analysis, together with whole-genome sequence analysis. Our dataset consists of 28 distinct immune cell subsets from 337 patients diagnosed with 10 categories of immune-mediated diseases and 79 healthy volunteers. Our dataset captured distinctive gene-expression profiles across immune cell types and diseases. Expression quantitative trait loci (eQTL) analysis revealed dynamic variations of eQTL effects in the context of immunological conditions, as well as cell types. These cell-type-specific and context-dependent eQTLs showed significant enrichment in immune disease-associated genetic variants, and they implicated the disease-relevant cell types, genes, and environment. This atlas deepens our understanding of the immunogenetic functions of disease-associated variants under in vivo disease conditions.


Assuntos
Regulação da Expressão Gênica/genética , Expressão Gênica/imunologia , Doenças do Sistema Imunitário/genética , Adulto , Feminino , Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Doenças do Sistema Imunitário/metabolismo , Doenças do Sistema Imunitário/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Locos de Características Quantitativas/imunologia , Transcriptoma/genética , Sequenciamento Completo do Genoma/métodos
4.
JBMR Plus ; 4(7): e10367, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32666018

RESUMO

Prolonged signaling at the parathyroid hormone receptor 1 (PTHR1) correlates with the capacity of a ligand to bind to a G protein-independent receptor conformation (R0). As long-acting PTH (LA-PTH) ligands hold interest as potential treatments for hypoparathyroidism (HP), we explored the structural basis in the ligand for stable R0 binding and prolonged cAMP signaling. A series of PTH/PTHrP hybrid analogs were synthesized and tested for actions in vitro and in vivo. Of the series, [Ala1,3,12,Gln10,Arg11,Trp14]-PTH(1-14)/PTHrP(15-36) (M-PTH/PTHrP) bound with high affinity to R0, induced prolonged cAMP responses in UMR106 rat osteoblast-derived cells, and induced the most prolonged increases in serum calcium (sCa) in normal rats. Daily s.c. injection of M-PTH/PTHrP into thyroparathyroidectomized (TPTX) rats, a model of HP, normalized sCa without raising urine Ca. In contrast, oral alfacalcidol, a widely used treatment for HP, normalized sCa, but induced frank hypercalciuria. M-PTH/PTHrP exhibited low solubility in aqueous solutions of neutral pH; however, replacement of Leu18, Phe22, and His26 with the less hydrophobic residues, Ala, Ala, and Lys, at those respective positions markedly improved solubility while maintaining bioactivity. Indeed, we recently showed that the resultant analog [Ala18,22,Lys26]-M-PTH/PTHrP or LA-PTH, effectively normalizes sCa in TPTX rats and mediates prolonged actions in monkeys. These studies provide useful information for optimizing PTH and PTHrP ligand analogs for therapeutic development. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

5.
J Bone Miner Res ; 31(7): 1405-12, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26865415

RESUMO

Hypoparathyroidism is a disease of chronic hypocalcemia and hyperphosphatemia due to a deficiency of parathyroid hormone (PTH). PTH and analogs of the hormone are of interest as potential therapies. Accordingly, we examined the pharmacological properties of a long-acting PTH analog, [Ala(1,3,12,18,22) , Gln(10) ,Arg(11) ,Trp(14) ,Lys(26) ]-PTH(1-14)/PTHrP(15-36) (LA-PTH) in thyroparathyroidectomized (TPTX) rats, a model of HP, as well as in normal monkeys. In TPTX rats, a single intravenous administration of LA-PTH at a dose of 0.9 nmol/kg increased serum calcium (sCa) and decreased serum phosphate (sPi) to near-normal levels for longer than 48 hours, whereas PTH(1-34) and PTH(1-84), each injected at a dose 80-fold higher than that used for LA-PTH, increased sCa and decreased sPi only modestly and transiently (<6 hours). LA-PTH also exhibited enhanced and prolonged efficacy versus PTH(1-34) and PTH(1-84) for elevating sCa when administered subcutaneously (s.c.) into monkeys. Daily s.c. administration of LA-PTH (1.8 nmol/kg) into TPTX rats for 28 days elevated sCa to near normal levels without causing hypercalciuria or increasing bone resorption markers, a desirable goal in the treatment of hypoparathyroidism. The results are supportive of further study of long-acting PTH analogs as potential therapies for patients with hypoparathyroidism. © 2016 American Society for Bone and Mineral Research.


Assuntos
Hipoparatireoidismo/tratamento farmacológico , Hormônio Paratireóideo , Paratireoidectomia , Animais , Biomarcadores/sangue , Reabsorção Óssea/sangue , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Células HEK293 , Humanos , Hipercalciúria/sangue , Hipoparatireoidismo/sangue , Macaca fascicularis , Masculino , Hormônio Paratireóideo/análogos & derivados , Hormônio Paratireóideo/farmacocinética , Hormônio Paratireóideo/farmacologia , Ratos
6.
Sci Rep ; 6: 22010, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26915424

RESUMO

The Fukushima Dai-ichi Nuclear Power Plant accident in March 2011 released radiocaesium ((137)Cs and (134)Cs) into the North Pacific Ocean. Meridional transects of the vertical distribution of radiocaesium in seawater were measured along 147 °E and 155 °E in October-November 2012, 19 months after the accident. These measurements revealed subsurface peaks in radiocaesium concentrations at locations corresponding to two mode waters, Subtropical Mode Water and Central Mode Water. Mode water is a layer of almost vertically homogeneous water found over a large geographical area. Here we show that repeated formation of mode water during the two winter seasons after the Fukushima accident and subsequent outcropping into surface water transported radiocaesium downward and southward to subtropical regions of the North Pacific. The total amount of Fukushima-derived (134)Cs within Subtropical Mode Water, decay-corrected to April 2011, was estimated to be 4.2 ± 1.1 PBq in October-November 2012. This amount of (134)Cs corresponds to 22-28% of the total amount of (134)Cs released to the Pacific Ocean.

7.
J Bone Miner Res ; 30(10): 1803-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25891861

RESUMO

Hypocalcemia and hyperphosphatemia are encountered in idiopathic hypoparathyroidism (IHP) and pseudohypoparathyroidism type Ib (PHP1B). In contrast to PHP1B, which is caused by resistance toward parathyroid hormone (PTH), the genetic defects leading to IHP impair production of this important regulator of mineral ion homeostasis. So far, only five PTH mutations were shown to cause IHP, each of which is located in the hormone's pre-pro leader segment and thus impair hormone secretion. In three siblings affected by IHP, we now identified a homozygous arginine-to-cysteine mutation at position 25 (R25C) of the mature PTH(1-84) polypeptide; heterozygous family members are healthy. Depending on the assay used for evaluating these patients, plasma PTH levels were either low or profoundly elevated, thus leading to ambiguities regarding the underlying diagnosis, namely IHP or PHP1B. Consistent with increased PTH levels, recombinant [Cys25]PTH(1-84) and wild-type PTH(1-84) were secreted equally well by transfected COS-7 cells. However, synthetic [Cys25]PTH(1-34) was found to have a lower binding affinity for the PTH receptor type-1 (PTH1R) than PTH(1-34) and consequently a lower efficiency for stimulating cAMP formation in cells expressing this receptor. Consistent with these in vitro findings, long-term infusion of [Cys25]PTH(1-34) resulted only in minimal calcemic and phosphaturic responses, despite readily detectable levels of [Cys25]PTH(1-34) in plasma. The mineral ion abnormalities observed in the three IHP patients are thus most likely caused by the inherited homozygous missense PTH mutation, which reduces bioactivity of the secreted hormone. Based on these findings, screening for PTH(1-84) mutations should be considered when clinical and laboratory findings are consistent with PHP1B, but GNAS methylation changes have been excluded. Differentiating between IHP and PHP1B has considerable implications for genetic counseling, therapy, and long-term outcome because treatment of IHP patients with inappropriately high doses of active vitamin D and calcium can contribute to development of nephrocalcinosis and chronic kidney disease.


Assuntos
Homozigoto , Hipoparatireoidismo , Mutação de Sentido Incorreto , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo , Substituição de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Humanos , Hipoparatireoidismo/genética , Hipoparatireoidismo/metabolismo , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/genética
8.
PLoS One ; 10(4): e0121801, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25875179

RESUMO

Short-time tracking (one to eight days) of the Japanese eel (Anguilla japonica) using ultrasonic transmitter was performed in the tropical-subtropical area adjacent to the spawning area and temperate area off the Japanese Archipelago. Of 16 eels (11 wild and five farmed) used, 10 wild eels displayed clear diel vertical migration (DVM) from the beginning, while the other five farmed eels tracked for 19 to 66 hours did not. During daytime, a significantly positive correlation between migration depth and light intensity recorded on the vessel was observed in the 10 wild eels, indicating that the eels were sensitive to sunlight even at the middle to lower mesopelagic zone (500 to 800 m). During nighttime, the eel migration depth was observed to be associated with the phase, rising and setting of the moon, indicating that the eels were sensitive to moonlight at the upper mesopelagic zone (<300 m). Two of 10 wild eels were in the yellow stage but shared similar DVM with the silver stage eels. Swimbladders of three silver stage eels were punctured before releasing, but very little effect on DVM was observed. The eels very punctually initiated descent upon nautical dawn and ascent upon sunset, enabling us to determine local times for sunrise and sunset, and hence this behavior may be used for geolocating eels. In fact, estimated positions of eels based on the depth trajectory data were comparable or even better than those obtained by light-based archival tag in other fish species.


Assuntos
Migração Animal/fisiologia , Enguias/fisiologia , Animais , Luz
9.
Proc Natl Acad Sci U S A ; 110(15): 5864-9, 2013 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-23533279

RESUMO

Agonist-induced phosphorylation of the parathyroid hormone (PTH) receptor 1 (PTHR1) regulates receptor signaling in vitro, but the role of this phosphorylation in vivo is uncertain. We investigated this role by injecting "knock-in" mice expressing a phosphorylation-deficient (PD) PTHR1 with PTH ligands and assessing acute biologic responses. Following injection with PTH (1-34), or with a unique, long-acting PTH analog, PD mice, compared with WT mice, exhibited enhanced increases in cAMP levels in the blood, as well as enhanced cAMP production and gene expression responses in bone and kidney tissue. Surprisingly, however, the hallmark hypercalcemic and hypophosphatemic responses were markedly absent in the PD mice, such that paradoxical hypocalcemic and hyperphosphatemic responses were observed, quite strikingly with the long-acting PTH analog. Spot urine analyses revealed a marked defect in the capacity of the PD mice to excrete phosphate, as well as cAMP, into the urine in response to PTH injection. This defect in renal excretion was associated with a severe, PTH-induced impairment in glomerular filtration, as assessed by the rate of FITC-inulin clearance from the blood, which, in turn, was explainable by an overly exuberant systemic hypotensive response. The overall findings demonstrate the importance in vivo of PTH-induced phosphorylation of the PTHR1 in regulating acute ligand responses, and they serve to focus attention on mechanisms that underlie the acute calcemic response to PTH and factors, such as blood phosphate levels, that influence it.


Assuntos
Osso e Ossos/metabolismo , Rim/metabolismo , Hormônio Paratireóideo/análogos & derivados , Receptor Tipo 1 de Hormônio Paratireóideo/fisiologia , Animais , Cálcio/sangue , Cálcio/urina , AMP Cíclico/sangue , AMP Cíclico/urina , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Técnicas de Introdução de Genes , Homeostase , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatos/sangue , Fosfatos/urina , Fosforilação , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Tempo
10.
PLoS One ; 6(12): e29280, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22195038

RESUMO

The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142-1,207 bp) and 16S rDNA (535-546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY).


Assuntos
Variação Genética , Palinuridae/genética , Animais , Pareamento de Bases/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genética Populacional , Geografia , Larva/genética , Dados de Sequência Molecular , Oceano Pacífico , Filogenia , Polimorfismo Genético , Análise de Sequência de DNA
11.
Bone ; 48(4): 713-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21111078

RESUMO

Once-daily injections of teriparatide initially increase biochemical markers of bone formation and resorption, but markers peak after 6-12 months and then decline despite continued treatment. We sought to determine whether increasing teriparatide doses in a stepwise fashion could prolong skeletal responsiveness. We randomized 52 postmenopausal women with low spine and/or hip bone mineral density (BMD) to either a constant or an escalating subcutaneous teriparatide dose (30 µg daily for 18months or 20 µg daily for 6 months, then 30 µg daily for 6 months, and then 40 µg daily for 6 months). Serum procollagen I N-terminal propeptide, osteocalcin, and C-terminal telopeptide of type I collagen were assessed frequently. BMD of the spine, hip, radius, and total body was measured every 6 months. Acute changes in urinary cyclic AMP in response to teriparatide were examined in a subset of women in the constant dose group. All bone markers differed significantly between the two treatment groups. During the final six months, bone markers declined in the constant dose group but remained stable or increased in the escalating dose group (all markers, p<0.017). Nonetheless, mean area under the curve did not differ between treatments for any bone marker, and BMD increases were equivalent in both treatment groups. Acute renal response to teriparatide, as assessed by urinary cyclic AMP, did not change over 18 months of teriparatide administration. In conclusion, stepwise increases in teriparatide prevented the decline in bone turnover markers that is observed with chronic administration without altering BMD increases. The time-dependent waning of the response to teriparatide appears to be bone-specific.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Teriparatida/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Conservadores da Densidade Óssea/administração & dosagem , AMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Pessoa de Meia-Idade , Cooperação do Paciente , Pós-Menopausa , Teriparatida/administração & dosagem
12.
J Biol Chem ; 286(2): 1618-26, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21047792

RESUMO

The parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor (PTHR1) in cells of the renal proximal tubule mediates the reduction in membrane expression of the sodium-dependent P(i) co-transporters, NPT2a and NPT2c, and thus suppresses the re-uptake of P(i) from the filtrate. In most cell types, the liganded PTHR1 activates Gα(S)/adenylyl cyclase/cAMP/PKA (cAMP/PKA) and Gα(q/11)/phospholipase C/phosphatidylinositol 1,4,5-trisphosphate (IP(3))/Ca(2+)/PKC (IP(3)/PKC) signaling pathways, but the relative roles of each pathway in mediating renal regulation P(i) transport remain uncertain. We therefore explored the signaling mechanisms involved in PTH-dependent regulation of NPT2a function using potent, long-acting PTH analogs, M-PTH(1-28) (where M = Ala(1,12), Aib(3), Gln(10), Har(11), Trp(14), and Arg(19)) and its position 1-modified variant, Trp(1)-M-PTH(1-28), designed to be phospholipase C-deficient. In cell-based assays, both M-PTH(1-28) and Trp(1)-M-PTH(1-28) exhibited potent and prolonged cAMP responses, whereas only M-PTH(1-28) was effective in inducing IP(3) and intracellular calcium responses. In opossum kidney cells, a clonal cell line in which the PTHR1 and NPT2a are endogenously expressed, M-PTH(1-28) and Trp(1)-M-PTH(1-28) each induced reductions in (32)P uptake, and these responses persisted for more than 24 h after ligand wash-out, whereas that of PTH(1-34) was terminated by 4 h. When injected into wild-type mice, both M-modified PTH analogs induced prolonged reductions in blood P(i) levels and commensurate reductions in NPT2a expression in the renal brush border membrane. Our findings suggest that the acute down-regulation of NPT2a expression by PTH ligands involves mainly the cAMP/PKA signaling pathway and are thus consistent with the elevated blood P(i) levels seen in pseudohypoparathyroid patients, in whom Gα(s)-mediated signaling in renal proximal tubule cells is defective.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Hormônio Paratireóideo/metabolismo , Pseudo-Hipoparatireoidismo/metabolismo , Transdução de Sinais/fisiologia , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/metabolismo , Animais , Células COS , Bovinos , Chlorocebus aethiops , Regulação para Baixo/fisiologia , Humanos , Técnicas In Vitro , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gambás , Osteoblastos/citologia , Osteoblastos/metabolismo , Hormônio Paratireóideo/análogos & derivados , Hormônio Paratireóideo/genética , Fósforo/sangue , Ratos , Sódio/metabolismo
13.
Proc Natl Acad Sci U S A ; 105(43): 16525-30, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18946036

RESUMO

The parathyroid hormone receptor (PTHR) is a class B G protein-coupled receptor that plays critical roles in bone and mineral ion metabolism. Ligand binding to the PTHR involves interactions to both the amino-terminal extracellular (N) domain, and transmembrane/extracellular loop, or juxtamembrane (J) regions of the receptor. Recently, we found that PTH(1-34), but not PTH-related protein, PTHrP(1-36), or M-PTH(1-14) (M = Ala/Aib(1),Aib(3),Gln(10),Har(11),Ala(12),Trp(14),Arg(19)), binds to the PTHR in a largely GTPgammaS-resistant fashion, suggesting selective binding to a novel, high-affinity conformation (R(0)), distinct from the GTPgammaS-sensitive conformation (RG). We examined the effects in vitro and in vivo of introducing the M substitutions, which enhance interaction to the J domain, into PTH analogs extended C-terminally to incorporate residues involved in the N domain interaction. As compared with PTH(1-34), M-PTH(1-28) and M-PTH(1-34) bound to R(0) with higher affinity, produced more sustained cAMP responses in cells, formed more stable complexes with the PTHR in FRET and subcellular localization assays, and induced more prolonged calcemic and phosphate responses in mice. Moreover, after 2 weeks of daily injection in mice, M-PTH(1-34) induced larger increases in trabecular bone volume and greater increases in cortical bone turnover, than did PTH(1-34). Thus, the putative R(0) PTHR conformation can form highly stable complexes with certain PTH ligand analogs and thereby mediate surprisingly prolonged signaling responses in bone and/or kidney PTH target cells. Controlling, via ligand analog design, the selectivity with which a PTH ligand binds to R(0), versus RG, may be a strategy for optimizing signaling duration time, and hence therapeutic efficacy, of PTHR agonist ligands.


Assuntos
Peptídeos/metabolismo , Receptor Tipo 1 de Hormônio Paratireóideo/química , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Transdução de Sinais , Animais , Osso e Ossos/fisiologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Humanos , Rim/fisiologia , Ligantes , Camundongos , Ligação Proteica , Estrutura Terciária de Proteína , Ratos , Fatores de Tempo
14.
Mutat Res ; 643(1-2): 29-35, 2008 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-18598706

RESUMO

Glycogen synthase kinase 3 (GSK3) is an attractive novel pharmacological target. Inhibition of GSK3 is recently regarded as one of the viable approaches to therapy for Alzheimer's disease, cancer, diabetes mellitus, osteoporosis, and bipolar mood disorder. Here, we have investigated the aneugenic potential of two potent and highly specific inhibitors of GSK3 by using an in vitro micronucleus test with human lymphoblastoid TK6 cells. One inhibitor was a newly synthesized maleimide derivative and the other was a previously known aminopyrimidine derivative. Both compounds elicited statistically significant and concentration-dependent increases in micronucleated cells. One hundred micronuclei (MN) of each were analyzed using centromeric DNA staining with fluorescence in situ hybridization. Both the two structurally distinct compounds induced centromere-positive micronuclei (CMN). Calculated from the frequency of MN cells and the percentage of CMN, CMN cell incidence after treatment with the maleimide compound at 1.2 microM, 2.4 microM, and 4.8 microM was 11.6, 27.7, and 56.3 per 1000 cells, respectively; the negative control was 4.5. CMN cell incidence after the treatment with the aminopyrimidine compound at 1.8 microM, 3.6 microM, and 5.4 microM was 6.7, 9.8 and 17.2 per 1000 cells, respectively. Both compounds exhibited concentration-dependent increase in the number of mitotic cells. The frequency of CMN cells correlated well with mitotic cell incidence after treatment with either compound. Furthermore, both inhibitors induced abnormal mitotic cells with asymmetric mitotic spindles and lagging anaphase chromosomes. These results lend further support to the hypothesis that the inhibition of GSK3 activity affects microtubule function and exhibits an aneugenic mode of action.


Assuntos
Aneugênicos/farmacologia , Centrômero/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Linfócitos/efeitos dos fármacos , Pirimidinas/farmacologia , Western Blotting , Núcleo Celular/genética , Centrômero/fisiologia , Citometria de Fluxo , Imunofluorescência , Humanos , Hibridização in Situ Fluorescente/métodos , Linfócitos/citologia , Linfócitos/metabolismo , Maleimidas/farmacologia , Testes para Micronúcleos/métodos , Microtúbulos/fisiologia , Fuso Acromático/efeitos dos fármacos , Fuso Acromático/genética
15.
J Clin Invest ; 116(2): 528-35, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16424941

RESUMO

Although active vitamin D drugs have been used for the treatment of osteoporosis, how the vitamin D receptor (VDR) regulates bone cell function remains largely unknown. Using osteoprotegerin-deficient mice, which exhibit severe osteoporosis due to excessive receptor activator of NF-kappaB ligand/receptor activator of NF-kappaB (RANKL/RANK) stimulation, we show herein that oral treatment of these mice with 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] inhibited bone resorption and prevented bone loss, suggesting that VDR counters RANKL/RANK signaling. In M-CSF-dependent osteoclast precursor cells isolated from mouse bone marrow, 1alpha,25(OH)2D3 potently and dose-dependently inhibited their differentiation into multinucleate osteoclasts induced by RANKL. Among signaling molecules downstream of RANK, 1alpha,25(OH)2D3 inhibited the induction of c-Fos protein after RANKL stimulation, and retroviral expression of c-Fos protein abrogated the suppressive effect of 1alpha,25(OH)2D3 on osteoclast development. By screening vitamin D analogs based on their c-Fos-suppressing activity, we identified a new analog, named DD281, that inhibited bone resorption and prevented bone loss in ovariectomized mice, more potently than 1alpha,25(OH)2D3, with similar levels of calcium absorption. Thus, c-Fos protein is an important target of the skeletal action of VDR-based drugs, and DD281 is a bone-selective analog that may be useful for the treatment of bone diseases with excessive osteoclastic activity.


Assuntos
Conservadores da Densidade Óssea/metabolismo , Calcitriol/análogos & derivados , Calcitriol/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Conservadores da Densidade Óssea/uso terapêutico , Reabsorção Óssea/prevenção & controle , Calcitriol/uso terapêutico , Proteínas de Transporte/metabolismo , Diferenciação Celular/fisiologia , Feminino , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoprotegerina , Ovariectomia , Proteínas Proto-Oncogênicas c-fos/genética , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/citologia , Células-Tronco/metabolismo
16.
Int Immunopharmacol ; 5(12): 1731-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16102523

RESUMO

To characterize the biological activity of tocilizumab, a humanized anti-human interleukin-6 receptor (IL-6R) monoclonal antibody, we examined its binding activity to both soluble IL-6R (sIL-6R) and membrane bound IL-6R (mIL-6R) and its neutralizing activity to other IL-6 family cytokines. ELISA assay demonstrated that tocilizumab bound to sIL-6R and inhibited IL-6 binding to sIL-6R in a dose-dependent manner. The dissociation constant (Kd value) for IL-6R was determined to be 2.54+/-0.12 nmol/L by Scatchard analysis. In addition, tocilizumab had the ability to dissociate IL-6 and sIL-6R from their preformed complex. The immune complex of tocilizumab and sIL-6R did not transmit signaling. Moreover, tocilizumab suppressed the IL-6/sIL-6R complex-induced proliferation of human gp130-transfected cell, BAF-h130. In addition, tocilizumab had the ability to bind to human IL-6R expressing COS-7 cells and to suppress the growth of the IL-6-dependent myeloma cell line, KPMM2. Finally, to analyze the specificity of this antibody, the effects on signal transduction of IL-6 family cytokines such as interleukin-11 (IL-11), oncostatin M (OSM), leukemia inhibitory factor (LIF), and ciliary neurotrophic factor (CNTF) were examined using murine transfectant cell lines (BaF/IL-6R, BaF/IL-11R, BaF/OSMR, BaF/LIFR and BaF/CNTFR) that proliferate depending on IL-6, IL-11, OSM, LIF and human CNTF, respectively. Tocilizumab inhibited the proliferation of BaF/IL-6R induced by IL-6, but did not inhibit the proliferation of BaF/IL-11R, BaF/OSMR, BaF/LIFR and BaF/CNTFR cells induced by their corresponding cytokines. These lines of evidence indicate that tocilizumab is able to bind to both sIL-6R and mIL-6R and to inhibit IL-6 binding to its receptors, leading to the blockade of the IL-6 signaling through both sIL-6R and mIL-6R, but not block the signaling of other IL-6 family cytokines.


Assuntos
Anticorpos Monoclonais/farmacologia , Citocinas/imunologia , Receptores de Interleucina-6/imunologia , Transdução de Sinais/efeitos dos fármacos , Animais , Anticorpos Monoclonais Humanizados , Células COS , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Humanos , Interleucina-6/imunologia , Interleucina-6/metabolismo , Ligação Proteica , Receptores de Citocinas/imunologia , Receptores de Citocinas/metabolismo , Receptores de Interleucina-6/metabolismo , Transdução de Sinais/imunologia , Transfecção
17.
Osteoarthritis Cartilage ; 13(4): 287-96, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15780642

RESUMO

OBJECTIVE: To examine the chondrogenic activity of AG-041R and its mode of action in a bipotent chondroprogenitor cell line CL-1. DESIGN: Chondrogenic activity of AG-041R in CL-1 was examined by histology, alcian blue pH 1.0 intensity and mRNA expression of cartilage matrix proteins (collagen type II, aggrecan). Chondrogenic activities of other CCK2/gastrin receptor antagonists were also examined. Since TGF-beta1 induces dominant chondrogenesis and suppressed adipogenesis in CL-1, induction of TGF-beta by AG-041R was examined by enzyme linked immunosorbent assay. Involvement of MAP kinases in the chondrogenic effect of AG-041R in CL-1 was examined by Western blotting and MAP kinase inhibitors. RESULTS: AG-041R induced dominant chondrogenesis and marked suppression of adipogenesis in CL-1. Neither of the other CCK2/gastrin receptor antagonists tested showed chondrogenic activity in CL-1. AG-041R increased alcian blue pH 1.0 intensity and mRNA expression of collagen type II and aggrecan. TGF-beta1 and -beta2 proteins were increased by AG-041R. The chondrogenic activity of AG-041R in CL-1 was blocked by TGF-beta neutralizing antibody or inhibitors for activation of latent TGF-beta. AG-041R activated both Erk (p44/42) and p38 MAP kinases in CL-1. Inhibition of Erk (p44/42) by PD98059 canceled the adipogenesis suppression by AG-041R in CL-1. Inhibition of p38 by SB202190 completely canceled the chondrogenic activity of AG-041R in CL-1. CONCLUSION: AG-041R has chondrogenic activity in CL-1 not related to CCK2/gastrin receptor antagonism. It is suggested that TGF-beta induction and the activation of MAP kinases mediate the chondrogenic activity of AG-041R in CL-1.


Assuntos
Condrócitos/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Indóis/farmacologia , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Condrócitos/citologia , Condrócitos/fisiologia , Condrogênese/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Receptor de Colecistocinina B/antagonistas & inibidores , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/biossíntese
18.
Nihon Geka Gakkai Zasshi ; 104(10): 711-6, 2003 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-14579757

RESUMO

Many studies have reported the benefit of hepatic resection for metastatic tumors from colorectal cancer. However, the significance of hepatic resection for gastric metastasis has been controversial. Peritoneal metastases were recognized in 40% of gastric cancer patients with liver metastases, and metastatic lesions in both lobes of the liver were seen in 60% of patients. Resection with curability B was performed in only 10% of the all gastric cancer patients with liver metastases. However, the overall 5-year survival rate of curability B resection was more than 30%, suggesting that it is worth while treating metastases of gastric cancer to the liver. Both synchronous and metachronous metastases are indications for hepatectomy. If there is only one liver metastasis, with no peritoneal and paraaortic lymph node metastases, curability B resection can be performed. Although there is no consensus on the method of hepatectomy, wedge resection is satisfactory. As systemic chemotherapy, S-1 + cisplatin results in a response rate of 50% in patients with metastases to the liver. As arterial infusion chemotherapy, the 5-fluorouracil-doxorubicin-mitomycin (FAM) regimen yields a response rate of more than 70% including 15% complete response rate. FAM is thus a superior regimen, but care must be taken to prevent complications resulting from intraarterial infusion of outside the vas due to deviation of the catheter.


Assuntos
Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Gástricas/patologia , Hepatectomia , Humanos
19.
Immunol Lett ; 84(3): 231-40, 2002 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-12413742

RESUMO

Hybridoma that produces rat anti-mouse interleukin 6 receptor (IL-6R) antibody, MR16-1, was established by the fusion of mouse P3U1 myeloma cells and spleen cells from mouse soluble IL-6R (sIL-6R)-immunized Wistar rat. In the present study, we examined the characteristics of MR16-1 in vitro and in vivo. MR16-1 bound to mouse sIL-6R dose-dependently. MR16-1 suppressed IL-6-induced proliferation of 7TD1 cells in a dose-dependent manner and this inhibitory effect was reversed by the addition of a higher concentration of IL-6. Cross-reactivity study using T cells from mouse, rat, and human revealed that MR16-1 did not cross-react with human and rat IL-6R. Binding region analysis using several human-mouse chimeric IL-6Rs showed that half of the fibronectin domain II of mouse IL-6R (amino acids 214-285) was required for MR16-1 binding. Furthermore, MR16-1 completely suppressed IL-6-induced antibody production in DNP-KLH immunized mice. These lines of evidence demonstrate that MR16-1 is useful to investigate the physiological and pathological roles of IL-6 and sIL-6R in mice.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos/imunologia , Receptores de Interleucina-6/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/farmacologia , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Células COS , Humanos , Hibridomas/efeitos dos fármacos , Hibridomas/imunologia , Interleucina-6/imunologia , Interleucina-6/farmacologia , Camundongos , Dados de Sequência Molecular , Ratos , Receptores de Interleucina-6/antagonistas & inibidores , Especificidade da Espécie
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