RESUMO
Sensorimotor dysfunction following incomplete spinal cord injury (SCI) is often characterized by paralysis, spasticity and pain. Previously, we showed that intrathecal (i.t.) administration of the albumin-oleic acid (A-OA) complex in rats with SCI produced partial improvement of these symptoms and that oral 2-hydroxyoleic acid (HOA, a non-hydrolyzable OA analogue), was efficacious in the modulation and treatment of nociception and pain-related anxiety, respectively. Here we observed that intrathecal treatment with the complex albumin-HOA (A-HOA) every 3 days following T9 spinal contusion injury improved locomotor function assessed with the Rotarod and inhibited TA noxious reflex activity in Wistar rats. To investigate the mechanism of action of A-HOA, microarray analysis was carried out in the spinal cord lesion area. Representative genes involved in pain and neuroregeneration were selected to validate the changes observed in the microarray analysis by quantitative real-time RT-PCR. Comparison of the expression between healthy rats, SCI rats, and SCI treated with A-HOA rats revealed relevant changes in the expression of genes associated with neuronal morphogenesis and growth, neuronal survival, pain and inflammation. Thus, treatment with A-HOA not only induced a significant overexpression of growth and differentiation factor 10 (GDF10), tenascin C (TNC), aspirin (ASPN) and sushi-repeat-containing X-linked 2 (SRPX2), but also a significant reduction in the expression of prostaglandin E synthase (PTGES) and phospholipases A1 and A2 (PLA1/2). Currently, SCI has very important unmet clinical needs. A-HOA downregulated genes involved with inflammation and upregulated genes involved in neuronal growth, and may serve to promote recovery of function after experimental SCI.
Assuntos
Albuminas/farmacologia , Ácidos Oleicos/farmacologia , Dor/prevenção & controle , Paralisia/tratamento farmacológico , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Albuminas/química , Animais , Esquema de Medicação , Proteínas da Matriz Extracelular/agonistas , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Fator 10 de Diferenciação de Crescimento/agonistas , Fator 10 de Diferenciação de Crescimento/genética , Fator 10 de Diferenciação de Crescimento/metabolismo , Injeções Espinhais , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Nociceptividade/efeitos dos fármacos , Ácidos Oleicos/química , Dor/genética , Dor/metabolismo , Dor/patologia , Paralisia/genética , Paralisia/metabolismo , Paralisia/patologia , Fosfolipases/antagonistas & inibidores , Fosfolipases/genética , Fosfolipases/metabolismo , Prostaglandina-E Sintases/antagonistas & inibidores , Prostaglandina-E Sintases/genética , Prostaglandina-E Sintases/metabolismo , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Teste de Desempenho do Rota-Rod , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Tenascina/agonistas , Tenascina/genética , Tenascina/metabolismo , Resultado do TratamentoRESUMO
The thyroid gland secretes primarily tetraiodothyronine (T4), and some triiodothyronine (T3). Under normal physiological circumstances, only one-fifth of circulating T3 is directly released by the thyroid, but in states of hyperactivation of thyroid-stimulating hormone receptors (TSHRs), patients develop a syndrome of relative T3 toxicosis. Thyroidal T4 production results from iodination of thyroglobulin (TG) at residues Tyr5 and Tyr130, whereas thyroidal T3 production may originate in several different ways. In this study, the data demonstrate that within the carboxyl-terminal portion of mouse TG, T3 is formed de novo independently of deiodination from T4 We found that upon iodination in vitro, de novo T3 formation in TG was decreased in mice lacking TSHRs. Conversely, de novo T3 that can be formed upon iodination of TG secreted from PCCL3 (rat thyrocyte) cells was augmented from cells previously exposed to increased TSH, a TSHR agonist, a cAMP analog, or a TSHR-stimulating antibody. We present data suggesting that TSH-stimulated TG phosphorylation contributes to enhanced de novo T3 formation. These effects were reversed within a few days after removal of the hyperstimulating conditions. Indeed, direct exposure of PCCL3 cells to human serum from two patients with Graves' disease, but not control sera, led to secretion of TG with an increased intrinsic ability to form T3 upon in vitro iodination. Furthermore, TG secreted from human thyrocyte cultures hyperstimulated with TSH also showed an increased intrinsic ability to form T3 Our data support the hypothesis that TG processing in the secretory pathway of TSHR-hyperstimulated thyrocytes alters the structure of the iodination substrate in a way that enhances de novo T3 formation, contributing to the relative T3 toxicosis of Graves' disease.
Assuntos
Processamento de Proteína Pós-Traducional , Receptores da Tireotropina/agonistas , Transdução de Sinais , Tireoglobulina/metabolismo , Células Epiteliais da Tireoide/metabolismo , Tireotropina/metabolismo , Tri-Iodotironina/biossíntese , Animais , Proteínas de Ligação ao Cálcio/agonistas , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Linhagem Celular , Células Cultivadas , Proteínas da Matriz Extracelular/agonistas , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Doença de Graves/sangue , Doença de Graves/metabolismo , Doença de Graves/patologia , Halogenação , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Receptores da Tireotropina/genética , Receptores da Tireotropina/metabolismo , Células Epiteliais da Tireoide/citologia , Células Epiteliais da Tireoide/patologia , Tirosina/metabolismo , Regulação para CimaRESUMO
The multiple physiological effects of γ-aminobutyric acid (GABA) as a functional food component have been recently reported. We previously reported that GABA upregulated the expression of type I collagen in human dermal fibroblasts (HDFs), and that oral administration of GABA significantly increased skin elasticity. However, details of the regulatory mechanism still remain unknown. In this study, we further examined the effects of GABA on elastin synthesis and elastin fiber formation in HDFs. Real-time PCR indicated that GABA significantly increased the expression of tropoelastin transcript in a dose-dependent manner. Additionally, the expression of fibrillin-1, fibrillin-2, and fibulin-5/DANCE, but not lysyl oxidase and latent transforming factor-ß-binding protein 4, were also significantly increased in HDFs. Finally, immunohistochemical analysis confirmed that treatment with GABA dramatically increased the formation of elastic fibers in HDFs. Taken together, our results showed that GABA improves skin elasticity in HDFs by upregulating elastin synthesis and elastin fiber formation.
Assuntos
Tecido Elástico/efeitos dos fármacos , Elastina/genética , Fibroblastos/efeitos dos fármacos , Tropoelastina/agonistas , Ácido gama-Aminobutírico/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Derme/citologia , Derme/efeitos dos fármacos , Derme/metabolismo , Tecido Elástico/metabolismo , Elastina/agonistas , Elastina/metabolismo , Proteínas da Matriz Extracelular/agonistas , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Fibrilina-1/agonistas , Fibrilina-1/genética , Fibrilina-1/metabolismo , Fibrilina-2/agonistas , Fibrilina-2/genética , Fibrilina-2/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas de Ligação a TGF-beta Latente/genética , Proteínas de Ligação a TGF-beta Latente/metabolismo , Proteína-Lisina 6-Oxidase/genética , Proteína-Lisina 6-Oxidase/metabolismo , Transdução de Sinais , Tropoelastina/genética , Tropoelastina/metabolismoRESUMO
Calcium, in combination with vitamin D, is an effective treatment for osteoporosis. Since bone mineralisation occurs concurrently with osteoblast to osteocyte transition, we hypothesised that calcium would stimulate this process. The effect of calcium (1.8-11.8mM) was tested on human primary osteoblast (NHBC) differentiation in vitro. Cultures were assayed for cell-associated mineral and gene expression associated with osteoblast differentiation and mineralisation. Treatment with calcium resulted in a striking dose- and time-dependent increase in cell-associated mineralisation. Calcium appeared to promote osteoblast to osteocyte differentiation, as indicated by increased expression of osteocalcin (OCN), E11, dentin matrix protein 1 (DMP1) and SOST mRNA. The expression of the osteoclast inhibitor, osteoprotegerin, was dramatically enhanced by calcium. Calcium also increased the ratio of PHEX mRNA expression relative to that of MEPE, suggesting a mechanism for the pro-anabolic effect. Consistent with this, calcium-dependent mineralisation was reversed in the presence of MEPE-ASARM peptides. This study suggests that calcium promotes osteoblast to osteocyte transition and concurrent matrix mineralisation, at least in part through the PHEX-MEPE axis.