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1.
J Steroid Biochem Mol Biol ; 236: 106428, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37984748

RESUMEN

In the currently prevailing pig husbandry systems, the vitamin D status is almost exclusively dependent on dietary supply. Additional endogenous vitamin D production after exposure to ultraviolet-B (UVB) light might allow the animals to utilize minerals in a more efficient manner, as well as enable the production of functional vitamin D-enriched meat for human consumption. In this study, growing pigs (n = 16) were subjected to a control group or to a daily narrowband UVB exposure of 1 standard erythema dose (SED) for a period of 9 weeks until slaughter at a body weight of 105 kg. Transcriptomic profiling of liver with emphasis on the associated effects on vitamin D metabolism due to UVB exposure were evaluated via RNA sequencing. Serum was analyzed for vitamin D status and health parameters such as minerals and biochemical markers. The serum concentration of calcidiol, but not calcitriol, was significantly elevated in response to UVB exposure after 17 days on trial. No effects of UVB exposure were observed on growth performance and blood test results. At slaughter, the RNA sequencing analyses following daily UVB exposure revealed 703 differentially expressed genes (DEGs) in liver tissue (adjusted p-value < 0.01). Results showed that molecular pathways for vitamin D synthesis (CYP2R1) rather than cholesterol synthesis (DHCR7) were preferentially initiated in liver. Gene enrichment (p < 0.05) was observed for reduced cholesterol/steroid biosynthesis, SNARE interactions in vesicular transport, and CDC42 signaling. Taken together, dietary vitamin D supply can be complemented via endogenous production after UVB exposure in pig husbandry, which could be considered in the development of functional foods.


Asunto(s)
Transcriptoma , Vitamina D , Humanos , Animales , Porcinos , Vitaminas , Rayos Ultravioleta , Colesterol , Minerales , Hígado/metabolismo
2.
Heliyon ; 9(6): e17180, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37342574

RESUMEN

Antibiotic resistance has been recognized as a public health threat in recent years, and mortality due to resistance is increasing alarmingly every year. Antibiotic resistance, among many factors, may arise due to the consumption of substandard antibiotic brands that provide subnormal levels of the drug in the blood. Post-market evaluation can provide important information in assessing pharmaceutical products in terms of quality, purity, and therapeutic aspects. Ciprofloxacin, a broad-spectrum antibiotic, has been used against a wide range of infectious diseases in Bangladesh. The present study aimed to determine the quality attributes of twenty-two commonly prescribed brands of ciprofloxacin 500 mg tablet collected from Dhaka city and the rural regions of Jessore. RP-HPLC coupled with UV-visible spectrophotometry was used to determine the potency of ciprofloxacin in tablets, and the zone of inhibition was determined using Kirby-Bauer's disc diffusion method to assess the antimicrobial efficacy against different strains of microorganisms. We found that 95.45% of brands (21 out of 22 brands) of ciprofloxacin tablets met United States Pharmacopoeia (USP) and British Pharmacopoeia (BP) specified potency, whereas one brand failed. From dissolution studies, we observed that 68.2% of brands (15 out of 22 brands) followed USP/NF dissolution test specifications, whereas 31.8% (7 out of 22 brands) failed to release 80% of the labeled amount of drug within 30 min. Drug release kinetics data showed that most brands followed the Weibull drug release kinetic model. Fit factor analysis exhibited that 8 brands out of 22 (36.4%) failed to comply similar dissolution profiles with the reference product. Minimum inhibitory concentrations, assessed against five bacterial strains, further showed good antimicrobial sensitivity by all brands.

4.
Front Genet ; 14: 955631, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959829

RESUMEN

Introduction: Copy number variations (CNVs) play a critical role in the pathogenesis of neurodevelopmental disorders (NDD) among children. In this study, we aim to identify clinically relevant CNVs, genes and their phenotypic characteristics in an ethnically underrepresented homogenous population of Bangladesh. Methods: We have conducted chromosomal microarray analysis (CMA) for 212 NDD patients with male to female ratio of 2.2:1.0 to identify rare CNVs. To identify candidate genes within the rare CNVs, gene constraint metrics [i.e., "Critical-Exon Genes (CEGs)"] were applied to the population data. Autism Diagnostic Observation Schedule-Second Edition (ADOS-2) was followed in a subset of 95 NDD patients to assess the severity of autism and all statistical tests were performed using the R package. Results: Of all the samples assayed, 12.26% (26/212) and 57.08% (121/212) patients carried pathogenic and variant of uncertain significance (VOUS) CNVs, respectively. While 2.83% (6/212) patients' pathogenic CNVs were found to be located in the subtelomeric regions. Further burden test identified females are significant carriers of pathogenic CNVs compared to males (OR = 4.2; p = 0.0007). We have observed an increased number of Loss of heterozygosity (LOH) within cases with 23.85% (26/109) consanguineous parents. Our analyses on imprinting genes show, 36 LOH variants disrupting 69 unique imprinted genes and classified these variants as VOUS. ADOS-2 subset shows severe social communication deficit (p = 0.014) and overall ASD symptoms severity (p = 0.026) among the patients carrying duplication CNV compared to the CNV negative group. Candidate gene analysis identified 153 unique CEGs in pathogenic CNVs and 31 in VOUS. Of the unique genes, 18 genes were found to be in smaller (<1 MB) focal CNVs in our NDD cohort and we identified PSMC3 gene as a strong candidate gene for Autism Spectrum Disorder (ASD). Moreover, we hypothesized that KMT2B gene duplication might be associated with intellectual disability. Conclusion: Our results show the utility of CMA for precise genetic diagnosis and its integration into the diagnosis, therapy and management of NDD patients.

5.
Br J Nutr ; 130(8): 1298-1307, 2023 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36847163

RESUMEN

Vitamin D3 (Vit D3) and 25(OH)D3 are used as dietary sources of active vitamin D (1,25(OH)2D3) in pig husbandry. Although acting primarily on intestine, kidney and bone, their use in pig nutrition has shown a wide range of effects also in peripheral tissues. However, there is an ambiguity in the existing literature about whether the effects of Vit D3 and 25(OH)D3 differ in attributing the molecular and phenotypic outcomes in pigs. We searched Web of Science and PubMed databases concerning the efficacy of Vit D3 in comparison with 25(OH)D3 on pig physiology, i.e. reproductive capacities, growth performance, immunity and bone development. Dietary intake of Vit D3 or 25(OH)D3 did not influence the reproductive capacity of sows. Unlike Vit D3, the maternal intake of 25(OH)D3 significantly improved the growth performance of piglets, which might be attributed to maternally induced micronutrient efficiency. Consequently, even in the absence of maternal vitamin D supplementation, 25(OH)D3-fed offspring also demonstrated better growth than the offspring received Vit D3. Moreover, a similar superior impact of 25(OH)D3 was seen with respect to serum markers of innate and humoral immunity. Last but not least, supplements containing 25(OH)D3 were found to be more effective than Vit D3 to improve bone mineralisation and formation, especially in pigs receiving basal diets low in Ca and phosphorus. The insights are of particular value in determining the principal dietary source of vitamin D to achieve its optimum utilisation efficiency, nutritional benefits and therapeutic potency and to further improve animal welfare across different management types.


Asunto(s)
Colecalciferol , Vitamina D , Animales , Porcinos , Femenino , Colecalciferol/farmacología , Dieta/veterinaria , Vitaminas , Suplementos Dietéticos , Desarrollo Óseo
6.
Metabolites ; 12(8)2022 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-36005601

RESUMEN

Calcium (Ca) and phosphorus (P) homeostasis is maintained by several regulators, including vitamin D and fibroblast growth factor 23 (FGF23), and their tissue-specific activation and signaling cascades. In this study, the tissue-wide expression of key genes linked to vitamin D metabolism (CYP2R1, CYP27A1, CYP27B1, CYP24A1, GC, VDR) and FGF23 signaling (FGF23, FGFR1-4, KL) were investigated in pigs fed conventional (trial 1) and divergent P diets (trial 2). The tissue set comprised kidney, liver, bone, lung, aorta, and gastrointestinal tract sections. Expression patterns revealed that non-renal tissues and cells (NRTC) express genes to form active vitamin D [1,25(OH)2D3] according to site-specific requirements. A low P diet resulted in higher serum calcitriol and increased CYP24A1 expression in the small intestine, indicating local suppression of vitamin D signaling. A high P diet prompted increased mRNA abundances of CYP27B1 for local vitamin D synthesis, specifically in bone. For FGF23 signaling, analyses revealed ubiquitous expression of FGFR1-4, whereas KL was expressed in a tissue-specific manner. Dietary P supply did not affect skeletal FGF23; however, FGFR4 and KL showed increased expression in bone at high P supply, suggesting regulation to balance mineralization. Specific NRTC responses influence vitamin D metabolism and P homeostasis, which should be considered for a thrifty but healthy P supply.

7.
Rev Med Virol ; 31(5): 1-12, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33426683

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the host cell by binding to angiotensin-converting enzyme 2 (ACE2) receptor. Other important proteins involved in this process include disintegrin and metalloproteinase domain-containing protein 17 (ADAM17) also known as tumour necrosis factor-α-converting enzyme and transmembrane serine protease 2. ACE2 converts angiotensin II (Ang II) to angiotensin (1-7), to balance the renin angiotensin system. Membrane-bound ACE2 ectodomain shedding is mediated by ADAM17 upon viral spike binding, Ang II overproduction and in several diseases. The shed soluble ACE2 (sACE2) retains its catalytic activity, but its precise role in viral entry is still unclear. Therapeutic sACE2 is claimed to exert dual effects; reduction of excess Ang II and blocking viral entry by masking the spike protein. Nevertheless, the paradox is why SARS-CoV-2 comorbid patients struggle to attain such benefit in viral infection despite having a high amount of sACE2. In this review, we discuss the possible detrimental role of sACE2 and speculate on a series of events where protease primed or non-primed virus-sACE2 complex might enter the host cell. As extracellular virus can bind many sACE2 molecules, sACE2 level could be reduced drastically upon endocytosis by the host cell. A consequential rapid rise in Ang II level could potentially aggravate disease severity through Ang II-angiotensin II receptor type 1 (AT1R) axis in comorbid patients. Hence, monitoring sACE2 and Ang II level in coronavirus disease 2019 comorbid patients are crucial to ensure safe and efficient intervention using therapeutic sACE2 and vaccines.


Asunto(s)
Enzima Convertidora de Angiotensina 2/metabolismo , COVID-19/enzimología , Proteína ADAM17/genética , Proteína ADAM17/metabolismo , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Animales , COVID-19/genética , COVID-19/virología , Comorbilidad , Humanos , Fragmentos de Péptidos/metabolismo , SARS-CoV-2/fisiología
8.
PLoS One ; 15(12): e0243706, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33306725

RESUMEN

The present study was conducted to assess the behavioral preventive measures and the use of medicines and herbal foods/products among the public in response to Covid-19. A cross-sectional survey comprised of 1222 participants was conducted from 27 June to 20 July 2020. Kruskal-Wallis test was used to identify the differences in behavioral preventive practices across different demographic categories. To identify the factors associated with the use of preventive medicines and herbal foods/products, multivariable logistic regression was performed. Most participants adopted the recommended preventive practices such as washing hands more frequently (87.5%), staying home more often (85.5%), avoiding crowds (86%), and wearing masks (91.6%). About half of the smokers reported a decreased rate of smoking during the pandemic. Also, 14.8% took medicines, 57.6% took herbal foods/products, and 11.2% took both medicines and herbal foods/products as preventive measure against Covid-19. Arsenicum album, vitamin supplements, and zinc supplements were the most commonly used preventive medicines. Gender, age, and fear of Covid-19 were significantly associated with the use of both preventive medicines and herbal foods/products. For the management of Covid-19 related symptoms, paracetamol, antihistamines, antibiotics, and mineral (zinc and calcium) supplements were used most often. Most participants sought information from non-medical sources while using medicines and herbal products. Moreover, potentially inappropriate and unnecessary use of certain drugs was identified.


Asunto(s)
COVID-19 , Suplementos Dietéticos , Conductas Relacionadas con la Salud , Preparaciones de Plantas/administración & dosificación , SARS-CoV-2 , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bangladesh/epidemiología , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/psicología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoinforme
9.
Immunol Cell Biol ; 93(7): 662-72, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25823994

RESUMEN

Although transforming growth factor-ß (TGF-ß) has been shown to positively regulate the development of murine T helper type 17 (Th17) cells, which of the intracellular signaling pathways are involved is controversial. We examined Smad-dependent and -independent signaling molecules downstream of the TGF-ß receptor (TGFßR) involved in Th17 differentiation of naive murine CD4(+)CD62L(+) T cells. During Th17 differentiation of wild-type T cells, Smad2/3 was phosphorylated, indicating activation of the canonical Smad pathway. T cells lacking TGFßRII did not differentiate into Th17, whereas T cells treated with a TGFßRI kinase inhibitor (SB-431542) or overexpression of inhibitory Smad7 retained a low amount of Th17 polarization despite absent Smad2/3 phosphorylation. Using protein antibody arrays we found an increase of expression and phosphorylation of the following Smad-independent signaling molecules in Th17-polarized wild-type T cells: AKT1(Tyr474), AKT2 (Ser474), ERK1-p44/42 MAPK(Tyr204), mTOR(Thr2446), p38 MAPK(Thr180), Rac1/cdc42(Ser71), SAPK/JNK(Tyr185) and SP1(Thr739). Pharmacological inhibition of AKT/mammalian target of rapamycin (mTOR) signaling with rapamycin or LY294002 decreased Th17 differentiation of wild-type T cells, and completely abolished interleukin-17 production in T cells with overexpression of Smad7. Rapamycin and LY294002 also decreased induced regulatory T cell differentiation, but only had minor additive effects to Smad7 overexpression. Finally, inhibitors of mitogen-activated protein kinase (MAPK) blocked in vitro polarization of Th17 cells. Our data show that Smad-dependent and -independent intracellular pathways contribute to murine Th17 differentiation.


Asunto(s)
Receptores de Factores de Crecimiento Transformadores beta/fisiología , Transducción de Señal/fisiología , Células Th17/metabolismo , Factor de Crecimiento Transformador beta/fisiología , Animales , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/metabolismo , Cromonas/farmacología , Interleucina-17/biosíntesis , Interleucina-17/genética , Linfopoyesis/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Morfolinas/farmacología , Fosfatidilinositol 3-Quinasas/fisiología , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas c-akt/fisiología , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/deficiencia , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Proteínas Smad/fisiología , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/efectos de los fármacos , Serina-Treonina Quinasas TOR/fisiología , Células Th17/citología
10.
Brain ; 138(Pt 4): 902-17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25665584

RESUMEN

Multiple sclerosis is a chronic autoimmune demyelinating disease of the central nervous system, which is thought to be triggered by environmental factors in genetically susceptible individuals leading to activation of autoreactive T lymphocytes. Large multi-centre genome-wide association studies have identified multiple genetic risk loci in multiple sclerosis. In this study, we investigated T cell transcriptomic changes in experimental autoimmune encephalomyelitis, an animal model for multiple sclerosis. We correlated these findings with the multiple sclerosis risk genes postulated by the most recent Immunochip analysis and found that multiple sclerosis susceptibility genes were significantly regulated in experimental autoimmune encephalomyelitis. Our data indicate that nine distinct genes associated with multiple sclerosis risk, Bach2, Il2ra, Irf8, Mertk, Odf3b, Plek, Rgs1, Slc30a7 and Thada, can be confirmed to be differentially regulated in pathogenic CD4(+) T cells. During the effector phase within the inflamed CNS, CD4(+) T cells undergo comprehensive transformation and we identified key transcription factors and signalling networks involved in this process. The transformation was linked to metabolic changes with the involvement of liver X receptor/retinoid X receptor signalling and cholesterol biosynthesis, which might control the T cell effector function in the central nervous system. Thus, our study confirms the involvement of multiple sclerosis risk genes in the pathophysiology of the animal model and sheds light on additional disease-relevant inflammatory networks.


Asunto(s)
Linfocitos T CD4-Positivos , Encefalomielitis Autoinmune Experimental/genética , Redes Reguladoras de Genes/genética , Esclerosis Múltiple/genética , Animales , Linfocitos T CD4-Positivos/patología , Encefalomielitis Autoinmune Experimental/patología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Esclerosis Múltiple/patología
11.
Nat Med ; 20(3): 272-82, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24531377

RESUMEN

The defective generation or function of regulatory T (Treg) cells in autoimmune disease contributes to chronic inflammation and tissue injury. We report the identification of FoxA1 as a transcription factor in T cells that, after ectopic expression, confers suppressive properties in a newly identified Treg cell population, herein called FoxA1(+) Treg cells. FoxA1 bound to the Pdl1 promoter, inducing programmed cell death ligand 1 (Pd-l1) expression, which was essential for the FoxA1(+) Treg cells to kill activated T cells. FoxA1(+) Treg cells develop primarily in the central nervous system in response to autoimmune inflammation, have a distinct transcriptional profile and are CD4(+)FoxA1(+)CD47(+)CD69(+)PD-L1(hi)FoxP3(-). Adoptive transfer of stable FoxA1(+) Treg cells inhibited experimental autoimmune encephalomyelitis in a FoxA1-and Pd-l1-dependent manner. The development of FoxA1(+) Treg cells is induced by interferon-ß (IFN-ß) and requires T cell-intrinsic IFN-α/ß receptor (Ifnar) signaling, as the frequency of FoxA1(+) Treg cells was reduced in Ifnb(-/-) and Ifnar(-/-) mice. In individuals with relapsing-remitting multiple sclerosis, clinical response to treatment with IFN-ß was associated with an increased frequency of suppressive FoxA1(+) Treg cells in the blood. These findings suggest that FoxA1 is a lineage-specification factor that is induced by IFN-ß and supports the differentiation and suppressive function of FoxA1(+) Treg cells.


Asunto(s)
Encefalomielitis Autoinmune Experimental/metabolismo , Regulación de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Esclerosis Múltiple Recurrente-Remitente/metabolismo , Linfocitos T Reguladores/citología , Adulto , Animales , Apoptosis , Antígeno B7-H1/metabolismo , Diferenciación Celular , Linaje de la Célula , Sistema Nervioso Central/metabolismo , Femenino , Humanos , Terapia de Inmunosupresión , Interferón beta/metabolismo , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Transducción de Señal , Linfocitos T Reguladores/inmunología , Factores de Transcripción/metabolismo
12.
J Neurosci ; 33(35): 14231-45, 2013 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-23986257

RESUMEN

Glioblastoma multiforme (GBM) is the most aggressive form of brain tumor. In general, tumor growth requires disruption of the tissue microenvironment, yet how this affects glioma progression is unknown. We studied program death-ligand (PD-L)1 in neurons and gliomas in tumors from GBM patients and associated the findings with clinical outcome. Remarkably, we found that upregulation of PD-L1 by neurons in tumor-adjacent brain tissue (TABT) associated positively with GBM patient survival, whereas lack of neuronal PD-L1 expression was associated with high PD-L1 in tumors and unfavorable prognosis. To understand the molecular mechanism of PD-L1 signaling in neurons, we investigated PD-L1 function in cerebellar and cortical neurons and its impact on gliomas. We discovered that neuronal PD-L1-induced caspase-dependent apoptosis of glioma cells. Because interferon (IFN)-ß induces PD-L1 expression, we studied the functional consequences of neuronal Ifnb gene deletion on PD-L1 signaling and function. Ifnb-/- neurons lacked PD-L1 and were defective in inducing glioma cell death; this effect was reversed on PD-L1 gene transfection. Ifnb-/- mice with intracerebral isografts survived poorly. Similar to the observations in GBM patients, better survival in wild-type mice was associated with high neuronal PD-L1 in TABT and downregulation of PD-L1 in tumors, which was defective in Ifnb-/- mice. Our data indicated that neuronal PD-L1 signaling in brain cells was important for GBM patient survival. Reciprocal PD-L1 regulation in TABT and tumor tissue could be a prognostic biomarker for GBM. Understanding the complex interactions between tumor and adjacent stromal tissue is important in designing targeted GBM therapies.


Asunto(s)
Antígeno B7-H1/genética , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Neuronas/metabolismo , Adulto , Anciano , Animales , Apoptosis , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/diagnóstico , Cerebelo/patología , Corteza Cerebral/patología , Femenino , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Glioblastoma/diagnóstico , Humanos , Interferón beta/genética , Interferón beta/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Pronóstico
13.
J Immunol ; 185(1): 345-56, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20525883

RESUMEN

A protective and anti-inflammatory role for CD1d-dependent NKT cells (NKTs) has been reported in experimental and human autoimmune diseases. However, their role in arthritis has been unclear, with conflicting reports of CD1d-dependent NKTs acting both as regulatory and disease-promoting cells in arthritis. These differing modes of action might be due to genetic differences of inbred mice and incomplete backcrossing of gene-modified mice. We therefore put special emphasis on controlling the genetic backgrounds of the mice used. Additionally, we used two different murine arthritis models, Ag-induced arthritis (AIA) and collagen-induced arthritis (CIA), to evaluate acute and chronic arthritis in CD1d knockout mice and mice depleted of NK1.1(+) cells. CD1d-deficient mice developed more severe AIA compared with wild-type littermates, with a higher degree of inflammation and proteoglycan depletion. Chronic arthritis in CIA was also worse in the absence of CD1d-dependent NKTs. Elevated levels of Ag-specific IFN-gamma production accompanied these findings rather than changes in IL-17alpha. Depletion of NK1.1(+) cells supported these findings in AIA and CIA. This report provides support for CD1d-dependent NKTs being suppressor cells in acute and chronic arthritis, likely via inhibition of arthritogenic Th1 cells. These results make CD1d-dependent NKTs an attractive target for therapeutic intervention.


Asunto(s)
Antígenos CD1d/fisiología , Artritis Experimental/inmunología , Artritis Experimental/patología , Epítopos de Linfocito T/inmunología , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Células TH1/inmunología , Células TH1/patología , Enfermedad Aguda , Animales , Antígenos CD1d/genética , Antígenos Ly/biosíntesis , Enfermedad Crónica , Colágeno Tipo II/toxicidad , Tolerancia Inmunológica/genética , Mediadores de Inflamación/fisiología , Depleción Linfocítica/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Subfamilia B de Receptores Similares a Lectina de Células NK/biosíntesis , Células T Asesinas Naturales/patología , Ratas , Células TH1/metabolismo
14.
Brain ; 133(Pt 4): 1067-81, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20354004

RESUMEN

Autoreactive CD4+ T lymphocytes play a vital role in the pathogenesis of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis. Since the discovery of T helper 17 cells, there is an ongoing debate whether T helper 1, T helper 17 or both subtypes of T lymphocytes are important for the initiation of autoimmune neuroinflammation. We examined peripheral blood CD4+ cells from patients with active and stable relapsing-remitting multiple sclerosis, and used mice with conditional deletion or over-expression of the transforming growth factor-beta inhibitor Smad7, to delineate the role of Smad7 in T cell differentiation and autoimmune neuroinflammation. We found that Smad7 is up-regulated in peripheral CD4+ cells from patients with multiple sclerosis during relapse but not remission, and that expression of Smad7 strongly correlates with T-bet, a transcription factor defining T helper 1 responses. Concordantly, mice with transgenic over-expression of Smad7 in T cells developed an enhanced disease course during experimental autoimmune encephalomyelitis, accompanied by elevated infiltration of inflammatory cells and T helper 1 responses in the central nervous system. On the contrary, mice with a T cell-specific deletion of Smad7 had reduced disease and central nervous system inflammation. Lack of Smad7 in T cells blunted T cell proliferation and T helper 1 responses in the periphery but left T helper 17 responses unaltered. Furthermore, frequencies of regulatory T cells were increased in the central nervous system of mice with a T cell-specific deletion and reduced in mice with a T cell-specific over-expression of Smad7. Downstream effects of transforming growth factor-beta on in vitro differentiation of naïve T cells to T helper 1, T helper 17 and regulatory T cell phenotypes were enhanced in T cells lacking Smad7. Finally, Smad7 was induced during T helper 1 differentiation and inhibited during T helper 17 differentiation. Taken together, the level of Smad7 in T cells determines T helper 1 polarization and regulates inflammatory cellular responses. Since a Smad7 deletion in T cells leads to immunosuppression, Smad7 may be a potential new therapeutic target in multiple sclerosis.


Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Esclerosis Múltiple/inmunología , Proteína smad7/fisiología , Células TH1/inmunología , Secuencia de Aminoácidos , Animales , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Datos de Secuencia Molecular , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Proteína smad7/biosíntesis , Proteína smad7/deficiencia , Células TH1/metabolismo
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