RESUMO
Blood monocytes are the principal reservoir for tissue macrophages in rheumatoid synovitis. Receptor-mediated adhesive interactions between circulating cells and the synovial venules initiate recruitment. These interactions have been studied primarily in cultured endothelial cells. Thus the functional activities of specific adhesion receptors, such as the endothelial selectins and the leukocytic integrins, have not been evaluated directly in diseased tissues. We therefore examined monocyte-microvascular interactions in rheumatoid synovitis by modifying the Stamper-Woodruff frozen section binding assay initially developed to study lymphocyte homing. Specific binding of monocytes to venules lined by low or high endothelium occurred at concentrations as low as 5 x 10(5) cells/ml. mAbs specific for P-selectin (CD62, GMP-140/PADGEM) blocked adhesion by > 90% in all synovitis specimens examined. In contrast, P-selectin-mediated adhesion to the microvasculature was either lower or absent in frozen sections of normal foreskin and placenta. mAbs specific for E-selectin (ELAM-1) blocked 20-50% of monocyte attachment in several RA synovial specimens but had no effect in others. mAbs specific for LFA-1, Mo1/Mac 1, the integrin beta 2-chain, and L-selectin individually inhibited 30-40% of adhesion. An mAb specific for the integrin beta 1-chain inhibited the attachment of elutriated monocytes up to 20%. We conclude that P-selectin associated with the synovial microvasculature initiates shear-resistant adhesion of monocytes in the Stamper-Woodruff assay and stabilizes bonds formed by other selectins and the integrins. Thus the frozen section binding assay permits direct evaluation of leukocyte-microvascular adhesive interactions in inflamed tissues and suggests a prominent role for P-selectin in monocyte recruitment in vivo.
Assuntos
Artrite Reumatoide/patologia , Adesão Celular , Endotélio Vascular/metabolismo , Microcirculação/fisiopatologia , Monócitos/metabolismo , Moléculas de Adesão Celular/metabolismo , Selectina E , Secções Congeladas , Humanos , Selectina L , Selectina-P , Glicoproteínas da Membrana de Plaquetas/metabolismo , Sinovite/patologia , Distribuição TecidualRESUMO
OBJECTIVES: Fatigue is an important systemic symptom of rheumatoid arthritis (RA) but has rarely been evaluated consistently after initiation of treatment in RA patients. This study examined the effects of adalimumab (HUMIRA, Abbott Laboratories, Abbott Park, IL, USA), a fully human, anti-tumor necrosis factor (anti-TNF) monoclonal antibody, on reducing fatigue in patients with RA. METHODS: A total of 1526 patients with RA were enrolled in 3 randomized, placebo-controlled clinical trials of adalimumab versus placebo plus methotrexate (MTX) or placebo plus standard antirheumatic therapies. Fatigue was assessed with the Functional Assessment of Chronic Illness Therapy (FACIT) fatigue scale questionnaire (which has been validated in RA) at baseline, mid-study, and at the end of the study. Logistic regression models were constructed using baseline demographic variables to test for treatment effect. In addition, sensitivity analyses were performed to determine the robustness of the data. RESULTS: At baseline in the 3 trials, patients' fatigue ranged from 27.9-29.7, representing considerable fatigue on the FACIT fatigue scale. Fatigue was significantly and consistently reduced in adalimumab-treated patients in the 3 clinical trials. Relative to placebo plus MTX, the adalimumab 40-mg-every-other-week dosage group reported statistically significantly less fatigue at all time points post-baseline. Improvements between adalimumab and placebo ranged from 3-7 points across all 3 trials, with a 3-4-point change representing a minimum clinically important difference. CONCLUSION: Adalimumab treatment was shown to significantly reduce fatigue in patients with moderate to severe RA. Changes in fatigue in all 3 trials were found to be clinically important.
Assuntos
Anti-Inflamatórios/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Antirreumáticos/administração & dosagem , Artrite Reumatoide/complicações , Fadiga/tratamento farmacológico , Fadiga/fisiopatologia , Metotrexato/administração & dosagem , Adalimumab , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Fadiga/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Resultado do TratamentoRESUMO
Peroxisome proliferator-activator receptors (PPAR) are involved in cholesterol homeostasis through the regulation of bile acids synthesis, composition, and reclamation. As ileal bile acid-binding protein (I-BABP) is thought to play a crucial role in the enterohepatic circulation of bile acids, we investigated whether I-BABP gene expression could also be affected by PPAR. Indeed, treatment with the PPARalpha-PPARbeta/delta agonist bezafibrate led to the up-regulation of I-BABP mRNA levels in the human intestine-derived Caco-2 cells. Cotransfections of the reporter-linked human I-BABP promoter (hI-BABP-2769/+44) together with PPAR and RXR expression vectors demonstrated that the fibrate-mediated induction of the I-BABP gene is dependent on PPARalpha or PPARbeta/delta. Using progressive 5' deletions of the hI-BABP promoter and sequence analysis, we identified a putative PPAR-binding site located at the position -198 and -186 upstream of the transcription initiation site. Electrophoretic mobility shift assays showed that the PPAR/RXR heterodimer can specifically bind to this PPRE-like motif. The deletion of the PPRE within the hI-BABP promoter abolished the PPAR-mediated transactivation in transient transfection assays. The regulation of the I-BABP promoter by PPAR appears species-specific, as the mouse I-BABP promoter, which lacks a conserved PPRE, was not responsive to exogenous PPAR expression in the presence of bezafibrate. Our findings show that the I-BABP gene may be a novel target for PPAR in humans and further emphasize the role for PPAR in the control of bile acid homeostasis.
Assuntos
Proteínas de Transporte/genética , Regulação da Expressão Gênica , Íleo/metabolismo , Glicoproteínas de Membrana/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Animais , Sequência de Bases , Bezafibrato/farmacologia , Sítios de Ligação , Células CACO-2 , Proteínas de Transporte/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Glicoproteínas de Membrana/biossíntese , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Elementos de Resposta/genética , Especificidade da EspécieRESUMO
This study assessed the impact of school-based social competence training on skills, social adjustment, and self-reported substance use of 282 sixth and seventh graders. Training emphasized broad-based competence promotion in conjunction with domain-specific application to substance abuse prevention. The 20-session program comprised six units: stress management, self-esteem, problem solving, substances and health information, assertiveness, and social networks. Findings indicated positive training effects on Ss' skills in handling interpersonal problems and coping with anxiety. Teacher ratings revealed improvements in Ss' constructive conflict resolution with peers, impulse control, and popularity. Self-report ratings indicated gains in problem-solving efficacy. Results suggest some preventive impact on self-reported substance use intentions and excessive alcohol use. In general, the program was found to be beneficial for both inner-city and suburban students.
Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/prevenção & controle , Promoção da Saúde/métodos , Ajustamento Social , População Suburbana , População Urbana , Adolescente , Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/psicologia , Connecticut , Feminino , Educação em Saúde/métodos , Humanos , Masculino , Fatores de RiscoRESUMO
Chondromas of the soft tissue are uncommon, benign tumors. They are most frequently found adjacent to periarticular tissues or tenosynovium with a predilection for the hands and feet. We report a case of a patient with a large, increasing tumor of the left foot. Because of subjective complaints and mechanical irritation the patient was scheduled for surgery. The preoperative radiological work-up showed popcorn like clusters of calcifications around the dorsum of the foot. The tumor mass was reduced using several incisions. Histology showed soft tissue chondromatosis of the foot without malignancy. Following the operative procedure, the patient was free of pain and able to wear normal shoes. This case illustrates the clinical and radiological characteristics as well as the surgical treatment of progressive soft tissue chondromatosis.
Assuntos
Condromatose Sinovial , Doenças do Pé , Adulto , Condroma/diagnóstico , Condromatose Sinovial/diagnóstico , Condromatose Sinovial/cirurgia , Diagnóstico Diferencial , Doenças do Pé/diagnóstico , Doenças do Pé/cirurgia , Humanos , Masculino , Neoplasias de Tecidos Moles/diagnóstico , Tomografia Computadorizada por Raios XRESUMO
Tobogganing is a very popular outdoor winter recreational activity. In order to elucidate the patterns of injuries associated with tobogganing all patients with an injury caused by falls from or collisions while on or being hit by a sled were sampled prospectively between the period of November 1996 and March 1997. 50 patients were included in this study, aged from 7 to 69 years (mean 25.5 years). Of these, 14 (= 28%) patients required admission to hospital lasting from 1 to 31 days (mean 13.5 days), 11 (22%) needed an operation. Over all we could register 55 injuries; the lower extremity was the region most commonly injured (63.6%), followed by upper extremity with 21.8%. The most common injury was the sprain of the knee. The most severe injuries could be found at the lower limb and at the vertebral column, including four fractures of the lower leg and 8 ankle-joint fractures as well as two fractures of the lumbar spine. The most common single procedure was the open reduction and internal fixation of a fibular fracture. In 48.6% of the cases the riders struck an object (tree, wall, post), while 32.4% fell from the toboggan caused by environmental conditions such as a bump or a ditch. The most important risk factor was an unadjusted speed referred to the environmental circumstances. Preventive strategies include tobogganing in adequate environmental conditions with no trees, no post or other stationary objects that could result in a collision. Speed should be adapted to the slope conditions.
Assuntos
Traumatismos em Atletas/epidemiologia , Neve , Aceleração , Adolescente , Adulto , Idoso , Traumatismos em Atletas/etiologia , Criança , Estudos Transversais , Feminino , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND AND AIMS: Faecal bile acid elimination greatly contributes to cholesterol homeostasis. Synthesised from cholesterol in the liver, bile acids are actively reclaimed in the ileum by the apical sodium dependent bile acid transporter (ASBT). Although the expression level of ASBT affects body cholesterol balance, the impact of cholesterol on ASBT gene expression remains unclear. In this study, the effect of cholesterol on ASBT expression and ileal bile acid uptake was explored in vivo and in vitro. METHODS: ASBT gene expression was assessed by real time quantitative polymerase chain reaction and northern or western blotting, or both, in mice subjected to a 2% cholesterol diet for two weeks, in mouse ileal explants, or in human enterocyte-like Caco-2 cells cultured in sterol enriched or depleted media. Bile acid uptake was determined by measuring [3H]-taurocholic acid influx into in situ isolated ileal loops from mice or into differentiated Caco-2 cells. Molecular analysis of mouse and human ASBT promoters was undertaken with reporter assays, site directed mutagenesis, and electrophoretic mobility shift assays. RESULTS: In mice, cholesterol enriched diet triggered a downregulation of ASBT expression (mRNA and protein), a fall in ileal bile acid uptake, and a rise in the faecal excretion of bile acids. This effect was direct as it was reproduced ex vivo using mouse ileal explants and in vitro in differentiated Caco-2 cells. CONCLUSIONS: This regulation, which involves an original partnership between SREBP-2 and HNF-1alpha transcription factors, affects ileal bile acid recycling and thus might participate in the maintenance of body cholesterol homeostasis.
Assuntos
Colesterol na Dieta/farmacologia , Regulação para Baixo/efeitos dos fármacos , Transportadores de Ânions Orgânicos Dependentes de Sódio/biossíntese , Simportadores/biossíntese , Animais , Sequência de Bases , Ácidos e Sais Biliares/metabolismo , Células CACO-2 , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Íleo/metabolismo , Absorção Intestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Técnicas de Cultura de Órgãos , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/fisiologia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/fisiologia , Simportadores/genética , Simportadores/fisiologia , TransfecçãoRESUMO
The activity pattern of Aotus lemurinus griseimembra can be predictably altered by varying the illuminance during the dark phase of a 12:12-hour light:dark rhythm. Intensities well below full-moon brightness (0.1-0.5 lx) severely inhibit activity. This modulation is not the result of a light-induced phase shift of the circadian rhythm, but it is primarily caused by masking due to direct effects of light on the motor system. Both proportional and differential effects of light are involved. Miniature transmitters were implanted intraperitoneally in two Aotus females so that the core temperature could be measured in parallel with locomotor activity. The responses to brief reductions of the dark-phase illuminance, from 10(-1) to 10(-3) lx, 10(-5) lx or physiological darkness, indicate that the direct effects of light that modulate the activity of the owl monkeys also affect their temperature time-course. The influence on the temperature rhythm, unlike that on the activity rhythm, varies greatly over the circadian period. The finding that the core temperature does not always change in parallel with locomotor activity and, to some extent, reacts differently to the light:dark alternation indicates that temperature does not simply follow activity passively, but rather is partially subject to a 'direct' masking influence of the light.
Assuntos
Aotus trivirgatus/fisiologia , Temperatura Corporal , Cebidae/fisiologia , Ritmo Circadiano , Luz , Atividade Motora/fisiologia , Animais , Variação Genética , Especificidade da EspécieRESUMO
Examined the impact of two subject variables (age and gender) and two contextual factors (antagonist age and nature of the social dilemma) on children's social problem solving (SPS). Preschoolers (N = 62) were individually presented with four stories that varied the antagonist age (peer vs. adult) and social dilemma (nonsexual vs. sexual). Responses were coded for three SPS variables: number of alternative solutions, solution content, and planfulness. Younger preschoolers were less competent problem solvers in all types of unsafe situations, and, compared to girls, some aspects of boys' problem solving were compromised in sexual encounters. Results also suggest that the nature of the social dilemma, but not the age of the antagonist, affects preschoolers' SPS. Children generated fewer alternative solutions and fewer effective strategies to the sexual encounters compared to the nonsexual dilemmas. Findings are discussed in relation to research on children's SPS and child sexual abuse prevention efforts.
Assuntos
Abuso Sexual na Infância/prevenção & controle , Educação em Saúde , Resolução de Problemas , Segurança , Meio Social , Assertividade , Criança , Abuso Sexual na Infância/psicologia , Pré-Escolar , Feminino , Identidade de Gênero , Humanos , Masculino , Grupo AssociadoRESUMO
The existence of a DNA polymorphism at the hormone-sensitive lipase locus could be of great interest for genetic analysis of obesity and related disorders since hormone-sensitive lipase is the rate-limiting enzyme of adipose tissue lipolysis and therefore plays a key role in energy metabolism. The polymorphic dinucleotide repeat D19S120 was identified within a human genomic clone selected with a rat hormone-sensitive lipase cDNA. This marker was subsequently localized to the short arm of chromosome 19 (p13.3) whereas human hormone-sensitive lipase (LIPE) had been mapped to the long arm of chromosome 19 (q13.1-->13.2). A duplication of the hormone-sensitive lipase gene or the presence of a pseudogene could explain the discrepancy. Cosmids from the two regions were analyzed in Southern blot experiments. A human adipose tissue hormone-sensitive lipase full-length cDNA probe hybridized only to cosmids from the 19q13.1-->13.2 region whereas the D19S120 amplicon probe hybridized only to cosmids from the p13.3 region. These data show that the occurrence of gene duplication or the presence of a pseudogene on the short arm of chromosome 19 is very unlikely and that D19S120 is unrelated to the hormone-sensitive lipase gene.
Assuntos
Cromossomos Humanos Par 19 , DNA/genética , Família Multigênica , Esterol Esterase/genética , Tecido Adiposo/enzimologia , Animais , Sequência de Bases , Southern Blotting , Cosmídeos , DNA/análise , DNA/química , Sondas de DNA/análise , Sondas de DNA/química , Sondas de DNA/genética , Metabolismo Energético/fisiologia , Humanos , Hibridização in Situ Fluorescente , Lipólise , Dados de Sequência Molecular , Obesidade/enzimologia , Obesidade/genética , Obesidade/fisiopatologia , Polimorfismo Genético , Ratos , Esterol Esterase/fisiologiaRESUMO
AIM: The aim of this study was to analyse the relation between the mobility of the thoracic spine and an impingement syndrome of the shoulder. METHOD: In a prospective study, 50 patients with an impingement syndrome and 50 healthy test subjects were examined for the mobility of their thoracic spines. All patients and test subjects were examined according to a standardized protocol. The experiments were carried out in the biomechanical laboratory of our clinic with the Plurimetercompass and the Inclinometer of Rippstein. RESULTS: In 23 patients a tendinosis calcarea was diagnosed radiologically, 27 patients suffered from a plain impingement without calcification, hence both groups were analyzed separately. The mobility of the thoracic spine in the sagittal and frontal planes and in rotation was significantly different between the three groups. The highest mobility was found in the healthy test subjects, the lowest in patients with a plain impingement. No differences were found concerning the initial posture of the thoracic spine. CONCLUSION: There is a relation between mobility of the thoracic spine and an impingement syndrome. This should be respected in diagnosis and therapy.
Assuntos
Calcinose/diagnóstico , Calcinose/patologia , Exame Físico/métodos , Amplitude de Movimento Articular , Síndrome de Colisão do Ombro/diagnóstico , Vértebras Torácicas/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The human HSL gene is composed of nine exons encoding the adipocyte form and a testis-specific coding exon. Northern blot analyses showed that human adipocytes express a 2.8 kb HSL mRNA, suggesting the presence of a short (20-150 bp) 5' untranslated region (5'-UTR). A single 5'-UTR of approx. 70 nt was detected in RNase H mapping experiments. Two 5'-UTRs of 70 and 170 nt respectively were obtained by rapid amplification of cDNA ends and cDNA library screenings. RNase protection experiments, with probes derived from the two products, showed that human adipocyte HSL mRNA contains only the 70 nt product. Primer extension analysis mapped the transcriptional start site 74 nt upstream of the start codon. In HT29, a human cell line expressing HSL, the presence of the short or the long 5'-UTR is mutually exclusive. The short and long 5'-UTR exons were located 1.5 and approx. 13 kb respectively upstream of the first coding exon. Various portions of the 5'-flanking region upstream of the short product exon were linked to the luciferase gene and transfected into cells that express HSL (HT29 cells and rat adipocytes) and do not express HSL (HeLa cells). High luciferase activity was found for constructs containing the sequence between nt -2400 and -86, but not for shorter constructs. An analysis of 14 kb of genomic sequence revealed the presence of five DNase I hypersensitive sites associated with active gene transcription. Three of the sites are located in the vicinity of the transcriptional start site and could be linked to the minimal promoter activity. Two of the sites are located downstream of the exon containing the start codon, suggesting the presence of intronic regulatory elements.
Assuntos
Adipócitos/enzimologia , Regiões Promotoras Genéticas , Esterol Esterase/genética , Animais , Sequência de Bases , Análise Mutacional de DNA , DNA Complementar/genética , Éxons , Expressão Gênica , Genoma Humano , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , Ratos , Proteínas Recombinantes de Fusão , Sequências Reguladoras de Ácido Nucleico , Deleção de Sequência , TransfecçãoRESUMO
Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The enzyme is also expressed in steroidogenic tissues, mammary gland, muscle tissues and macrophages. A novel HSL mRNA termed hHSL-S, 228 bp shorter than the full-length HSL mRNA, was detected in human adipocytes. hHSL-S mRNA results from the in-frame skipping of exon 6, which encodes the serine residue of the catalytic triad. The corresponding 80 kDa protein was identified in human adipocytes after immunoprecipitation. The truncated protein expressed in COS cells showed neither lipase nor esterase activity but was phosphorylated by cAMP-dependent protein kinase. hHSL-S mRNA was found in all human tissues expressing HSL, except brown adipose tissue from newborns. It represented approx. 20% of total HSL transcripts in human subcutaneous adipocytes. No alternative splicing was detected in other mammals. Human and mouse three-exon HSL minigenes transfected into primate and rodent cell lines reproduced the splicing pattern of the endogenous HSL genes. Analysis of hybrid human/mouse minigenes transfected into human cell lines showed that cis-acting elements responsible for the skipping of human exon 6 were restricted to a 247 bp region including exon 6 and the first 19 nt of intron 6. Moreover, divergence in exonic splicing elements between mouse and human was shown to be critical for the species-specific alternative splicing.
Assuntos
Processamento Alternativo , Esterol Esterase/genética , Esterol Esterase/metabolismo , Animais , Sequência de Bases , Células COS , Carcinoma Hepatocelular , Catálise , Ativação Enzimática/genética , Vetores Genéticos/biossíntese , Vetores Genéticos/fisiologia , Humanos , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , RNA Mensageiro/química , Ratos , Especificidade da Espécie , Esterol Esterase/química , Transfecção , Células Tumorais CultivadasRESUMO
Hormone-sensitive lipase (HSL) catalyses the rate-limiting step in adipocyte lipolysis. Short-term hormonal regulation of HSL activity is well characterized, whereas little is known about the control of HSL gene expression. We have measured HSL mRNA content of 3T3-F442A and BFC-1 adipocytes in response to the cAMP analogue 8-(4-chlorophenylthio)-cAMP (8-CPT-cAMP) and to the phorbol ester phorbol 12-myristate 13-acetate (PMA) by Northern blot, using a specific mouse cDNA fragment. Treatment of the cells for 12 or 6 h with, respectively, 0.5 mM 8-CPT-cAMP or 1 microM PMA produced a maximal decrease of about 60% in HSL mRNA. These effects were unaffected by the protein-synthesis inhibitor anisomycin, suggesting that cAMP and PMA actions were direct. The reduction in HSL mRNA was accompanied by a reduction in HSL total activity. The intracellular routes that cAMP and PMA follow for inducing such an effect seemed clearly independent. (i) After desensitization of the protein kinase C regulation pathway by a 24 h treatment of the cells with 1 microM PMA, PMA action was abolished whereas cAMP was still fully active. (ii) Treatment with saturating concentrations of both agents produced an additive effect. (iii) The synthetic glucocorticoid dexamethasone had no proper effect on HSL gene expression but potentiated cAMP action without affecting PMA action. cAMP inhibitory action on HSL is unexpected. Indeed, the second messenger of catecholamines is the main activator of HSL by phosphorylation. We envision that a long-term cAMP treatment of adipocytes induces a counter-regulatory process that reduces HSL content and, ultimately, limits fatty acid depletion from stored triacylglycerols.
Assuntos
AMP Cíclico/análogos & derivados , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Esterol Esterase/genética , Acetato de Tetradecanoilforbol/farmacologia , Tionucleotídeos/farmacologia , Células 3T3 , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Sequência de Bases , Linhagem Celular , AMP Cíclico/farmacologia , Primers do DNA/genética , Técnicas In Vitro , Isoproterenol/farmacologia , Masculino , Camundongos , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Transdução de SinaisRESUMO
Hormone-sensitive lipase expression was studied in the human colon adenocarcinoma cell line, HT29. Diacylglycerol lipase and cholesterol esterase [corrected] activities in HT29 cells were inhibited by known inhibitors of hormone-sensitive lipase (diethyl-p-nitrophenyl phosphate, NaF and HgCl2) to the same extent as in human adipocytes. A polyclonal antiserum directed against rat hormone-sensitive lipase inhibited 89% of HT29 cell lipase activity. HT29 hormone-sensitive lipase was the same size as the adipocyte enzyme as was its mRNA. Complete homology between mRNA sequences in HT29 and adipocyte was demonstrated using ribonuclease protection assay. These data are consistent with the expression of a protein closely related, if not identical, to the enzyme expressed in human adipose tissue. HT29 is the first human cell line where hormone-sensitive lipase expression has been shown.
Assuntos
Expressão Gênica , Esterol Esterase/biossíntese , Adenocarcinoma , Adipócitos/enzimologia , Animais , Anticorpos/farmacologia , Linhagem Celular , Galinhas , Ésteres do Colesterol/metabolismo , Neoplasias do Colo , Feminino , Humanos , Lipase Lipoproteica/antagonistas & inibidores , Lipase Lipoproteica/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos , Proteínas Recombinantes/biossíntese , Esterol Esterase/isolamento & purificação , Esterol Esterase/metabolismo , Células Tumorais CultivadasRESUMO
The testicular isoform of hormone-sensitive lipase (HSLtes) is encoded by a testis-specific exon and 9 exons common to the testis and adipocyte isoforms. In mouse, HSLtes mRNA appeared during spermiogenesis in round spermatids. Two constructs containing 1.4 and 0.5 kilobase pairs (kb) of the human HSLtes gene 5'-flanking region cloned upstream of the chloramphenicol acetyltransferase gene were microinjected into mouse oocytes. Analyses of enzyme activity in male and female transgenic mice showed that 0.5 kb of the HSLtes promoter was sufficient to direct expression only in testis. Cell transfection experiments showed that CREMtau, a testis-specific transcriptional activator, does not transactivate the HSLtes promoter. Using gel retardation assays, four testis-specific binding regions (TSBR) were identified using testis and liver nuclear extracts. The testis-specific protein binding on TSBR4 was selectively competed by a probe containing a SRY/Sox protein DNA recognition site. Sox5 and Sox6 which are expressed in post-meiotic germ cells bound TSBR4. Mutation of the AACAAAG motif in TSBR4 abolished the binding. Moreover, binding of the high mobility group domain of Sox5 induced a bend within TSBR4. Together, our results showed that 0.5 kb of the human HSLtes promoter bind Sox proteins and contain cis-acting elements essential for the testis specificity of HSL.
Assuntos
DNA/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Esterol Esterase/biossíntese , Testículo/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Humanos , Masculino , Meiose , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Quinases , Ribonuclease H/metabolismo , Ativação Transcricional , TransfecçãoRESUMO
Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step in adipocyte lipolysis. The activity of HSL is thought to be primarily regulated by reversible phosphorylation. However, the regulation of HSL activity by pre-translational mechanisms has been poorly studied. The present studies were undertaken to explore the relationship between the levels of HSL protein and mRNA expressions and the lipolytic capacity. The study was performed in human abdominal subcutaneous adipocytes with identical sizes but having either a high (HL) or low (LL) lipolytic capacity (n = 16). Basal and maximal lipolysis induced by catecholamines, an adenylyl cyclase activator forskolin, and a cyclic AMP analogue dibutyryl cAMP were 50% lower in LL- in comparison with HL-fat cells (P < 0.05 or better). No differences in drug sensitivity were found. HSL activity and quantity were about 50% lower in LL- compared with HL-fat cells (P < 0.05). Moreover, the mRNA ratio between HSL and gamma-actin was 35% lower in LL- compared with HL-fat cells (P < 0.05). There was a strong linear correlation between the protein and enzymatic HSL measurements (r2 = 0.91). In addition, the maximum lipolytic capacity was significantly correlated with HSL activity (r2 = 0.75) and HSL protein amount (r2 = 0.64). It is concluded that hormone-sensitive lipase (HSL) expression, measured either as total HSL protein by Western blot analysis or as total amount of activatable HSL enzyme, is a major determinant of the maximum lipolytic capacity of human fat cells. In addition, HSL protein expression is at least, in part, determined by HSL mRNA expression.
Assuntos
Adipócitos/metabolismo , Lipólise , Esterol Esterase/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/patologia , Adulto , Tamanho Celular , Feminino , Variação Genética , Humanos , Imunoquímica , Técnicas In Vitro , Isoproterenol/farmacologia , Cinética , Lipólise/efeitos dos fármacos , Masculino , Peso Molecular , Obesidade/enzimologia , Obesidade/metabolismo , Obesidade/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esterol Esterase/química , Esterol Esterase/genéticaRESUMO
By catalyzing the rate-limiting step in adipose tissue lipolysis, hormone-sensitive lipase (HSL) is an important regulator of energy homeostasis. The role and importance of HSL in tissues other than adipose are poorly understood. We report here the cloning and expression of a testicular isoform, designated HSLtes. Due to an addition of amino acids at the NH2-termini, rat and human HSLtes consist of 1068 and 1076 amino acids, respectively, compared to the 768 and 775 amino acids, respectively, of the adipocyte isoform (HSLadi). A novel exon of 1.2 kb, encoding the human testis-specific amino acids, was isolated and mapped to the HSL gene, 16 kb upstream of the exons encoding HSLadi. The transcribed mRNA of 3.9 kb was specifically expressed in testis. No significant similarity with other known proteins was found for the testis-specific sequence. The amino acid composition differs from the HSLadi sequence, with a notable hydrophilic character and a high content of prolines and glutamines. COS cells, transfected by the 3.9-kb human testis cDNA, expressed a protein of the expected molecular mass (M(r) approximately 120,000) that exhibited catalytic activity similar to that of HSLadi. Immunocytochemistry localized HSL to elongating spermatids and spermatozoa; HSL was not detected in interstitial cells.
Assuntos
Esterol Esterase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Clonagem Molecular , DNA Complementar , Éxons , Técnica Indireta de Fluorescência para Anticorpo , Expressão Gênica , Hormônios/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Homologia de Sequência de Aminoácidos , Testículo/metabolismoRESUMO
OBJECTIVE: Psoriatic arthritis (PsA) is often poorly responsive to 2nd line antirheumatic drug therapy. Sulfasalazine has recently gained wide acceptance in the treatment of rheumatoid arthritis, and beneficial effects have also been noted in ankylosing spondylitis and reactive arthritis. We report a double blind placebo controlled study of sulfasalazine in PsA. METHODS: Twenty-four patients with active PsA were randomized to receive either sulfasalazine (3 g/day) (n = 10) or placebo (n = 14) for 8 weeks, in a double blind manner, followed by an 8 week open label crossover phase for nonresponding placebo patients. RESULTS: Compared with placebo controls, sulfasalazine treated patients were significantly improved at Weeks 4 and 8 with respect to physician (p < 0.01) and patient (p < 0.05) global assessments. Duration of morning stiffness was significantly decreased at Week 8 (p < 0.01). Clinical variables of disease activity returned to baseline after a 4 week drug washout period in 5 evaluable patients. Six patients in the placebo group crossed over to an 8 week open label phase and demonstrated significant improvements in joint scores, 50 ft walking time, and global patient assessment. Sulfasalazine treated patients also showed significant improvements in cutaneous involvement. CONCLUSION: Sulfasalazine was effective in PsA, with efficacy observed as early as the 4th week of treatment. Longterm studies are needed to determine whether such therapy can modify disease outcome.