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1.
Int J Biol Macromol ; 268(Pt 2): 131940, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692554

RESUMEN

Composite edible films were developed by casting method using sunnhemp protein isolate (SHPI) and potato starch (PS) at various proportions (100:0, 90:10, 80:20; 70:30, 60:40, and 50:50) containing glycerol as a plasticizer and clove oil. All the edible films were evaluated for thickness, moisture content, solubility, swelling ratio, water activity. Further characterization of edible films was done on the basis of mechanical, optical, thermal and structural attributes along with morphology. Among all the films, composite film containing 50 % SHPI, 50 % PS and 1 % clove oil were having better characteristics. The solubility and WVP decreased, while the tensile strength and elongation at break of composite film increased with the inclusion of potato starch and clove oil. Intermolecular interactions in the composite film matrix were confirmed by FTIR and XRD analysis. SEM images confirmed the structural compactness and integrity of all the developed films. The amino acid composition of edible films indicated presence of most of the essential amino acids. The present finding of this research work shows that the utilization of sunnhemp protein in the development of biocomposite edible films represents an alternative opportunity of sustainable edible food packaging.


Asunto(s)
Aminoácidos , Aceite de Clavo , Películas Comestibles , Solanum tuberosum , Solubilidad , Almidón , Almidón/química , Solanum tuberosum/química , Aceite de Clavo/química , Aminoácidos/química , Aminoácidos/análisis , Embalaje de Alimentos/métodos , Proteínas de Plantas/química , Resistencia a la Tracción , Biopolímeros/química , Agua/química
2.
Arthritis Rheum ; 64(11): 3750-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22806328

RESUMEN

OBJECTIVE: It is generally believed that muscle weakness in patients with polymyositis and dermatomyositis is due to autoimmune and inflammatory processes. However, it has been observed that there is a poor correlation between the suppression of inflammation and a recovery of muscle function in these patients. This study was undertaken to examine whether nonimmune mechanisms also contribute to muscle weakness. In particular, it has been suggested that an acquired deficiency of AMP deaminase 1 (AMPD1) may be responsible for muscle weakness in myositis. METHODS: We performed comprehensive functional, behavioral, histologic, molecular, enzymatic, and metabolic assessments before and after the onset of inflammation in a class I major histocompatibility complex (MHC)-transgenic mouse model of autoimmune inflammatory myositis. RESULTS: Muscle weakness and metabolic disturbances were detectable in the mice prior to the appearance of infiltrating mononuclear cells. Force contraction analysis of muscle function revealed that weakness was correlated with AMPD1 expression and was myositis specific. Decreasing AMPD1 expression resulted in decreased muscle strength in healthy mice. Fiber typing suggested that fast-twitch muscles were converted to slow-twitch muscles as myositis progressed, and microarray results indicated that AMPD1 and other purine nucleotide pathway genes were suppressed, along with genes essential to glycolysis. CONCLUSION: These data suggest that an AMPD1 deficiency is acquired prior to overt muscle inflammation and is responsible, at least in part, for the muscle weakness that occurs in the mouse model of myositis. AMPD1 is therefore a potential therapeutic target in myositis.


Asunto(s)
AMP Desaminasa/genética , Glucólisis/genética , Debilidad Muscular/metabolismo , Músculo Esquelético/enzimología , Miositis/metabolismo , AMP Desaminasa/inmunología , Animales , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Glucólisis/inmunología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/patología , Ratones , Ratones Transgénicos , Morfolinos/farmacología , Actividad Motora/genética , Actividad Motora/inmunología , Contracción Muscular/genética , Contracción Muscular/inmunología , Fibras Musculares de Contracción Rápida/metabolismo , Fibras Musculares de Contracción Rápida/patología , Fibras Musculares de Contracción Lenta/metabolismo , Fibras Musculares de Contracción Lenta/patología , Debilidad Muscular/genética , Debilidad Muscular/inmunología , Músculo Esquelético/inmunología , Miositis/genética , Miositis/inmunología
3.
Arthritis Rheum ; 63(11): 3448-57, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21769834

RESUMEN

OBJECTIVE: Multinucleated cells are relatively resistant to classic apoptosis, and the factors initiating cell death and damage in myositis are not well defined. We hypothesized that nonimmune autophagic cell death may play a role in muscle fiber damage. Recent reports indicate that TRAIL may induce both NF-κB activation and autophagic cell death in other systems. We undertook this study to investigate the role of TRAIL in cell death and pathogenesis in vitro and in vivo, using myositis muscle tissues from humans and mice. METHODS: Gene expression profiling was performed in myositis patient and control muscle specimens. Immunohistochemistry analysis was performed to confirm the gene array findings. We also analyzed TRAIL-induced cell death (apoptosis and autophagy) and NF-κB activation in vitro in cultured cells. RESULTS: TRAIL was expressed predominantly in myositis muscle fibers, but not in biopsy specimens from normal or other dystrophic-diseased muscle. Autophagy markers were up-regulated in humans with myositis and in mouse models of myositis. TRAIL expression was restricted to regenerating/atrophic areas of muscle fascicles, blood vessels, and infiltrating lymphocytes. TRAIL induced NF-κB activation and IκB degradation in cultured cells that are resistant to TRAIL-induced apoptosis but that undergo autophagic cell death. CONCLUSION: Our data demonstrate that TRAIL is expressed in myositis muscle and may mediate both activation of NF-κB and autophagic cell death in myositis. Thus, this nonimmune pathway may be an attractive target for therapeutic intervention in myositis.


Asunto(s)
Autofagia/fisiología , Músculo Esquelético/metabolismo , Miositis/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Animales , Perfilación de la Expresión Génica , Humanos , Ratones , Ratones Transgénicos , Miositis/genética , FN-kappa B/genética , FN-kappa B/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/genética
4.
Am J Pathol ; 176(6): 2891-900, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20413686

RESUMEN

A deficiency of the dysferlin protein results in limb girdle muscular dystrophy type 2B and Miyoshi myopathy, with resulting plasma membrane abnormalities in myofibers. Many patients show muscle inflammation, but the molecular mechanisms that initiate and perpetuate this inflammation are not well understood. We previously showed abnormal activation of macrophages and hypothesized that activation of the inflammasome pathway may play a role in disease progression. To test this, we studied the inflammasome molecular platform in dysferlin-deficient human and mouse muscle. Consistent with our model, components of the NACHT, LRR and PYD-containing proteins (NALP)-3 inflammasome pathway were specifically up-regulated and activated in dysferlin-deficient but not in dystrophin-deficient and normal muscle. We demonstrate for the first time that normal primary skeletal muscle cells are capable of secreting IL-1beta in response to combined treatment with lipopolysaccharide and the P2X7 receptor agonist, benzylated ATP, suggesting that not only immune cells but also muscle cells can actively participate in inflammasome formation. In addition, we show that dysferlin-deficient primary muscle cells express toll-like receptors (TLRs; TLR-2 and TLR-4) and can efficiently produce IL-1beta in response to lipopolysaccharide and benzylated ATP. These data indicate that skeletal muscle is an active contributor of IL-1beta and strategies that interfere with this pathway may be therapeutically useful for patients with limb girdle muscular dystrophy type 2B.


Asunto(s)
Inflamación/metabolismo , Proteínas de la Membrana , Proteínas Musculares , Músculo Esquelético/fisiología , Músculo Esquelético/fisiopatología , Distrofia Muscular de Cinturas , Adenosina Trifosfato/química , Adenosina Trifosfato/farmacología , Adulto , Animales , Células Cultivadas , Progresión de la Enfermedad , Disferlina , Femenino , Humanos , Inflamación/genética , Inflamación/patología , Interleucina-1beta/metabolismo , Lipopolisacáridos/farmacología , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/citología , Músculo Esquelético/patología , Distrofia Muscular de Cinturas/genética , Distrofia Muscular de Cinturas/patología , Distrofia Muscular de Cinturas/fisiopatología , Mioblastos/citología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2X7 , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Regulación hacia Arriba , Adulto Joven
5.
Clin Cancer Res ; 23(19): 5666-5670, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28235882

RESUMEN

On September 4, 2014, the FDA approved pembrolizumab (KEYTRUDA; Merck Sharp & Dohme Corp.) with a recommended dose of 2 mg/kg every 3 weeks by intravenous infusion for the treatment of patients with unresectable or metastatic melanoma who have progressed following treatment with ipilimumab and, if BRAF V600 mutation positive, a BRAF inhibitor. Approval was based on demonstration of objective tumor responses with prolonged response durations in 89 patients enrolled in a randomized, multicenter, open-label, dose-finding, and activity-estimating phase 1 trial. The overall response rate (ORR) by blinded independent central review per RECIST v1.1 was 24% (95% confidence interval, 15-34); with 6 months of follow-up, 86% of responses were ongoing. The most common (≥20%) adverse reactions were fatigue, cough, nausea, pruritus, rash, decreased appetite, constipation, arthralgia, and diarrhea. Immune-mediated adverse reactions included pneumonitis, colitis, hepatitis, hypophysitis, and thyroid disorders. The benefits of the observed ORR with prolonged duration of responses outweighed the risks of immune-mediated adverse reactions in this life-threatening disease and represented an improvement over available therapy. Important regulatory issues in this application were role of durability of response in the evaluation of ORR for accelerated approval, reliance on data from a first-in-human trial, and strategies for dose selection. Clin Cancer Res; 23(19); 5666-70. ©2017 AACR.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Melanoma/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Supervivencia sin Enfermedad , Aprobación de Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Ipilimumab/administración & dosificación , Ipilimumab/efectos adversos , Masculino , Melanoma/genética , Melanoma/patología , Persona de Mediana Edad , Proteínas Proto-Oncogénicas B-raf/genética
6.
BMC Immunol ; 7: 2, 2006 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-16504066

RESUMEN

BACKGROUND: Autoimmune diseases are more prevalent in females than in males, whereas males have higher mortality associated with infectious diseases. To increase our understanding of this sexual dimorphism in the immune system, we sought to identify and characterize inherent differences in immune response programs in the spleens of male and female mice before, during and after puberty. RESULTS: After the onset of puberty, female mice showed a higher expression of adaptive immune response genes, while males had a higher expression of innate immune genes. This result suggested a requirement for sex hormones. Using in vivo and in vitro assays in normal and mutant mouse strains, we found that reverse signaling through FasL was directly influenced by estrogen, with downstream consequences of increased CD8+ T cell-derived B cell help (via cytokines) and enhanced immunoglobulin production. CONCLUSION: These results demonstrate that sexual dimorphism in innate and adaptive immune genes is dependent on puberty. This study also revealed that estrogen influences immunoglobulin levels in post-pubertal female mice via the Fas-FasL pathway.


Asunto(s)
Estrógenos/fisiología , Genes MHC Clase II , Caracteres Sexuales , Maduración Sexual/inmunología , Animales , Formación de Anticuerpos , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Estrógenos/farmacología , Proteína Ligando Fas , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Haptoglobinas/análisis , Interferón gamma/análisis , Activación de Linfocitos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos MRL lpr , Ratones Mutantes/genética , Proteína Amiloide A Sérica/análisis , Bazo/inmunología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Factores de Necrosis Tumoral/genética , Factores de Necrosis Tumoral/fisiología , Receptor fas/genética , Receptor fas/fisiología
7.
Oncogene ; 22(16): 2493-503, 2003 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-12717426

RESUMEN

The oncoprotein 70Z/3 Cbl signals in an autonomous fashion or through blockade of endogenous c-Cbl, a negative regulator of signaling. The mechanism of 70Z/3 Cbl-induced signaling was investigated by comparing the molecular requirements for 70Z/3 Cbl- and TCR-induced phospholipase C gamma 1 (PLC gamma 1) activation. 70Z/3 Cbl-induced PLC gamma 1 tyrosine phosphorylation required, in addition to the PLC gamma 1 N-terminal SH2 domain, the C-terminal SH2 and SH3 domains that were dispensable for TCR-induced phosphorylation. Deletion of the leucine zipper of 70Z/3 Cbl did not eliminate 70Z/3 Cbl-induced PLC gamma 1 phosphorylation, suggesting that blockage of c-Cbl via dimerization with 70Z/3 Cbl cannot fully explain 70Z/3 Cbl activating characteristics. The complete elimination of PLC gamma 1 phosphorylation required deleting the SH3 domain-binding region of 70Z/3 Cbl, consistent with 70Z/3 Cbl binding the PLC gamma 1 SH3 domain. 70Z/3 Cbl-induced PLC gamma 1 phosphorylation required Zap-70, as for the TCR, and the tyrosine kinase binding domain of 70Z/3 Cbl, which binds Zap-70, but did not require PLC gamma 1 binding to Lat, a crucial interaction in TCR-induced PLC gamma 1 phosphorylation. Furthermore, 70Z/3 Cbl-induced activation of NFAT, a PLC gamma 1/Ca(2+)-dependent transcriptional event, required Zap-70, but was independent of Slp-76, an adapter required for TCR-induced NFAT activation. These results suggest that 70Z/3 Cbl and PLC gamma 1 form a TCR-, Lat- and Slp-76-independent complex that leads to PLC gamma 1 phosphorylation and activation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas de la Membrana , Proteínas Nucleares , Proteínas Oncogénicas de Retroviridae/genética , Transducción de Señal/fisiología , Linfocitos T/metabolismo , Fosfolipasas de Tipo C/genética , Proteínas Portadoras/metabolismo , Proteínas de Unión al ADN/metabolismo , Humanos , Células Jurkat , Factores de Transcripción NFATC , Proteína Oncogénica v-cbl , Fosfohidrolasa PTEN , Fosfolipasa C gamma , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteína Tirosina Quinasa ZAP-70
8.
FEBS Lett ; 513(2-3): 203-7, 2002 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-11904151

RESUMEN

Macrophages respond to bacterial lipopolysaccharide (LPS) by activating latent cis-acting factors that initiate transcription of immediate early genes. One such immediate early gene, junB, is induced by LPS in macrophages within 30 min. To identify elements that mediate the induction of junB by LPS, upstream and downstream sequences flanking the junB gene were examined by transient expression in the RAW264.7 murine macrophage cell line using a luciferase reporter gene vector containing the junB minimal promoter. A >10-fold enhancement was associated with a 222 bp region downstream of the junB promoter in response to LPS. Transient reporter assays demonstrated that multiple nuclear factor (NF) kappaB sites are required for inducibility of junB by LPS in RAW264.7 cells. Electrophoretic mobility shift assays confirmed binding of LPS-induced nuclear proteins included p50/p65 heterodimers at these NF-kappaB sites.


Asunto(s)
Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-jun/biosíntesis , Animales , Línea Celular , Macrófagos/metabolismo , Ratones , Proteínas Proto-Oncogénicas c-jun/efectos de los fármacos
9.
PLoS One ; 5(6): e11220, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20574530

RESUMEN

BACKGROUND: The number of promising therapeutic interventions for Duchenne Muscular Dystrophy (DMD) is increasing rapidly. One of the proposed strategies is to use drugs that are known to act by multiple different mechanisms including inducing of homologous fetal form of adult genes, for example utrophin in place of dystrophin. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have treated mdx mice with arginine butyrate, prednisone, or a combination of arginine butyrate and prednisone for 6 months, beginning at 3 months of age, and have comprehensively evaluated the functional, biochemical, histological, and molecular effects of the treatments in this DMD model. Arginine butyrate treatment improved grip strength and decreased fibrosis in the gastrocnemius muscle, but did not produce significant improvement in muscle and cardiac histology, heart function, behavioral measurements, or serum creatine kinase levels. In contrast, 6 months of chronic continuous prednisone treatment resulted in deterioration in functional, histological, and biochemical measures. Arginine butyrate-treated mice gene expression profiling experiments revealed that several genes that control cell proliferation, growth and differentiation are differentially expressed consistent with its histone deacetylase inhibitory activity when compared to control (saline-treated) mdx mice. Prednisone and combination treated groups showed alterations in the expression of genes that control fibrosis, inflammation, myogenesis and atrophy. CONCLUSIONS/SIGNIFICANCE: These data indicate that 6 months treatment with arginine butyrate can produce modest beneficial effects on dystrophic pathology in mdx mice by reducing fibrosis and promoting muscle function while chronic continuous treatment with prednisone showed deleterious effects to skeletal and cardiac muscle. Our results clearly indicate the usefulness of multiple assays systems to monitor both beneficial and toxic effects of drugs with broad range of in vivo activity.


Asunto(s)
Arginina/análogos & derivados , Butiratos/farmacología , Corazón/efectos de los fármacos , Corazón/fisiopatología , Músculos/efectos de los fármacos , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/fisiopatología , Prednisona/farmacología , Animales , Arginina/farmacología , Arginina/uso terapéutico , Conducta Animal/efectos de los fármacos , Butiratos/uso terapéutico , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Ratones Endogámicos mdx , Músculos/metabolismo , Músculos/patología , Músculos/fisiopatología , Distrofia Muscular de Duchenne/tratamiento farmacológico , Distrofia Muscular de Duchenne/patología , Prednisona/uso terapéutico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo , Utrofina/metabolismo
10.
Muscle Nerve ; 39(5): 591-602, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19260102

RESUMEN

The availability of animal models for Duchenne muscular dystrophy has led to extensive preclinical research on potential therapeutics. Few studies have focused on reliability and sensitivity of endpoints for mdx mouse drug trials. Therefore, we sought to compare a wide variety of reported and novel endpoint measures in exercised mdx and normal control mice at 10, 20, and 40 weeks of age. Statistical analysis as well as power calculations for expected effect sizes in mdx preclinical drug trials across different ages showed that body weight, normalized grip strength, horizontal activity, rest time, cardiac function measurements, blood pressure, total central/peripheral nuclei per fiber, and serum creatine kinase are the most effective measurements for detecting drug-induced changes. These data provide an experimental basis upon which standardization of preclinical drug testing can be developed. Muscle Nerve, 2008.


Asunto(s)
Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Distrofia Muscular de Duchenne/patología , Distrofia Muscular de Duchenne/fisiopatología , Resultado del Tratamiento , Factores de Edad , Animales , Presión Sanguínea/genética , Peso Corporal/efectos de los fármacos , Diafragma/patología , Diafragma/fisiopatología , Electrocardiografía/métodos , Electromiografía , Prueba de Esfuerzo/métodos , Conducta Exploratoria/efectos de los fármacos , Conducta Exploratoria/fisiología , Fuerza de la Mano/fisiología , Locomoción/efectos de los fármacos , Locomoción/genética , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Actividad Motora/efectos de los fármacos , Actividad Motora/genética , Fuerza Muscular/efectos de los fármacos , Fuerza Muscular/genética , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiopatología , Distrofia Muscular de Duchenne/tratamiento farmacológico , Distrofia Muscular de Duchenne/genética , Reproducibilidad de los Resultados , Prueba de Desempeño de Rotación con Aceleración Constante/métodos , Sensibilidad y Especificidad
11.
Am J Pathol ; 172(3): 774-85, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18276788

RESUMEN

Dysferlin deficiency causes limb-girdle muscular dystrophy type 2B (LGMD2B; proximal weakness) and Miyoshi myopathy (distal weakness). Muscle inflammation is often present in dysferlin deficiency, and patients are frequently misdiagnosed as having polymyositis. Because monocytes normally express dysferlin, we hypothesized that monocyte/macrophage dysfunction in dysferlin-deficient patients might contribute to disease onset and progression. We therefore examined phagocytic activity, in the presence and absence of cytokines, in freshly isolated peripheral blood monocytes from LGMD2B patients and in the SJL dysferlin-deficient mouse model. Dysferlin-deficient monocytes showed increased phagocytic activity compared with control cells. siRNA-mediated inhibition of dysferlin expression in the J774 macrophage cell line resulted in significantly enhanced phagocytosis, both at baseline and in response to tumor necrosis factor-alpha. Immunohistochemical analysis revealed positive staining for several mononuclear cell activation markers in LGMD2B human muscle and SJL mouse muscle. SJL muscle showed strong up-regulation of endocytic proteins CIMPR, clathrin, and adaptin-alpha, and LGMD2B muscle exhibited decreased expression of decay accelerating factor, which was not dysferlin-specific. We further showed that expression levels of small Rho family GTPases RhoA, Rac1, and Cdc 42 were increased in dysferlin-deficient murine immune cells compared with control cells. Therefore, we hypothesize that mild myofiber damage in dysferlin-deficient muscle stimulates an inflammatory cascade that may initiate, exacerbate, and possibly perpetuate the underlying myofiber-specific dystrophic process.


Asunto(s)
Inflamación/genética , Proteínas de la Membrana/genética , Monocitos/fisiología , Proteínas Musculares/genética , Distrofia Muscular de Cinturas/genética , Fagocitosis/genética , Adolescente , Adulto , Anciano , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Disferlina , Femenino , Humanos , Inflamación/complicaciones , Masculino , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Monocitos/metabolismo , Proteínas Musculares/antagonistas & inhibidores , Proteínas Musculares/fisiología , Distrofia Muscular de Cinturas/etiología , ARN Interferente Pequeño/farmacología , Proteínas de Unión al GTP rho/metabolismo
12.
J Autoimmune Dis ; 3: 2, 2006 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-16504012

RESUMEN

BACKGROUND: While vascular and immune abnormalities are common in juvenile and adult dermatomyositis (DM), the molecular changes that contribute to these abnormalities are not clear. Therefore, we investigated pathways that facilitate new blood vessel formation and dendritic cell migration in dermatomyositis. METHODS: Muscle biopsies from subjects with DM (9 children and 6 adults) and non-myositis controls (6 children and 7 adults) were investigated by immunohistochemistry using antibodies that recognize existing (anti-CD146) and newly formed blood vessels (anti-alphaVbeta3) and mature dendritic cells (anti-DC-LAMP). Blood vessel quantification was performed by digitalized image analysis. Additional muscle biopsies from subjects with adult DM and non-myositis controls were used for global gene expression profiling experiments. RESULTS: A significant increase in neovascularization was found in muscle biopsies of DM patients; neovascularization (alphaVbeta3 positive capillaries and vessels per muscle fiber) was much higher in juvenile than in adult DM patients (control vs juvenile DM: Mean +/- SE: 0.06 +/- 0.01 vs 0.6 +/- 0.05; p < 0.0001 and control vs adult DM: Mean +/- SE: 0.60 +/- 0.1 vs 0.75 +/- 0.1; p = 0.051). Gene expression analysis demonstrated that genes that participate not only in angiogenesis but also in leukocyte trafficking and the complement cascade were highly up regulated in DM muscle in comparison to age matched controls. DC-LAMP positive dendritic cells were highly enriched at perivascular inflammatory sites in juvenile and adult DM patients along with molecules that facilitate dendritic cell transmigration and reverse transmigration (CD142 and CD31). CONCLUSION: These results suggest active neovascularization and endothelial cell activation in both juvenile and adult DM. It is likely that close association of monocytes with endothelial cells initiate rapid dendritic cell maturation and an autoimmune response in DM.

13.
J Immunol ; 174(10): 6233-7, 2005 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-15879121

RESUMEN

Phospholipase Cgamma (PLCgamma) is a ubiquitous gatekeeper of calcium mobilization and diacylglycerol-mediated events induced by the activation of Ag and growth factor receptors. The activity of PLCgamma is regulated through its controlled membrane translocation and tyrosine (Y) phosphorylation. Four activation-induced tyrosine phosphorylation sites have been previously described (Y472, Y771, Y783, and Y1254), but their specific roles in Ag receptor-induced PLCgamma1 activation are not fully elucidated. Unexpectedly, we found that the phosphorylation of a PLCgamma1 construct with all four sites mutated to phenylalanine was comparable with that observed with wild-type PLCgamma1, suggesting the existence of an unidentified site(s). Sequence alignment with known phosphorylation sites in PLCgamma2 indicated homology of PLCgamma1 tyrosine residue 775 (Y775) with PLCgamma2 Y753, a characterized phosphorylation site. Tyrosine 775 was characterized as a phosphorylation site using phospho-specific anti-Y775 antiserum, and by mutational analysis. Phosphorylation of Y775 did not depend on the other tyrosines, and point mutation of PLCgamma1 Y775, or the previously described Y783, substantially reduced AgR-induced calcium, NF-AT, and AP-1 activation. Mutation of Y472, Y771, and Y1254 had no effect on overall PLCgamma1 phosphorylation or activation. Although the concomitant mutation of Y775 and Y783 abolished downstream PLCgamma1 signaling, these two tyrosines were sufficient to reconstitute the wild-type response in the absence of functional Y472, Y771, and Y1254. These data establish Y775 as a critical phosphorylation site for PLCgamma1 activation and confirm the functional importance of Y783.


Asunto(s)
Receptores de Antígenos de Linfocitos B/fisiología , Receptores de Antígenos de Linfocitos T/fisiología , Transducción de Señal/inmunología , Fosfolipasas de Tipo C/metabolismo , Tirosina/metabolismo , Secuencia de Aminoácidos , Animales , Calcio/metabolismo , Bovinos , Línea Celular , Proteínas de Unión al ADN/metabolismo , Diglicéridos/fisiología , Humanos , Isoenzimas/deficiencia , Isoenzimas/genética , Isoenzimas/metabolismo , Células Jurkat , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Factores de Transcripción NFATC , Proteínas Nucleares/metabolismo , Fosfolipasa C gamma , Fosforilación , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal/genética , Factor de Transcripción AP-1/metabolismo , Factores de Transcripción/metabolismo , Transfección , Fosfolipasas de Tipo C/deficiencia , Fosfolipasas de Tipo C/genética , Tirosina/genética
14.
Arthritis Rheum ; 52(6): 1824-35, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15934115

RESUMEN

OBJECTIVE: The etiology and pathogenesis of human inflammatory myopathies remain unclear. Findings of several studies suggest that the degree of inflammation does not correlate consistently with the severity of clinical disease or of structural changes in the muscle fibers, indicating that nonimmune pathways may contribute to the pathogenesis of myositis. This study was undertaken to investigate these pathways in myositis patients and in a class I major histocompatibility complex (MHC)-transgenic mouse model of myositis. METHODS: We examined muscle tissue from human myositis patients and from class I MHC-transgenic mice for nonimmune pathways, using biochemical, immunohistochemical, and gene expression profiling assays. RESULTS: Up-regulation of class I MHC in skeletal muscle fibers was an early and consistent feature of human inflammatory myopathies. Class I MHC staining in muscle fibers of myositis patients showed both cell surface and a reticular pattern of internal reactivity. The pathways of endoplasmic reticulum (ER) stress response, the unfolded protein response (glucose-regulated protein 78 pathway), and the ER overload response (NF-kappaB pathway) were significantly activated in muscle tissue of human myositis patients and in the mouse model. Ectopic expression of wild-type mouse class I MHC (H-2K(b)) but not degradable glycosylation mutants of H-2K(b) induced ER stress response in C(2)C(12) skeletal muscle cells. CONCLUSION: These results indicate that the ER stress response may be a major nonimmune mechanism responsible for skeletal muscle damage and dysfunction in autoimmune myositis. Strategies to interfere with this pathway may have therapeutic value in patients with this disease.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Retículo Endoplásmico/inmunología , Miositis/inmunología , Estrés Fisiológico/inmunología , Animales , Enfermedades Autoinmunes/genética , Perfilación de la Expresión Génica , Genes MHC Clase I/inmunología , Humanos , Ratones , Ratones Transgénicos , Fibras Musculares Esqueléticas/inmunología , Fibras Musculares Esqueléticas/patología , Miositis/genética , Enfermedad Autoinmune Experimental del Sistema Nervioso , Estrés Fisiológico/genética
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