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1.
Int J Nanomedicine ; 15: 3903-3920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606657

RESUMO

Background: Researchers are trying to study the mechanism of neural stem cells (NSCs) differentiation to oligodendrocyte-like cells (OLCs) as well as to enhance the selective differentiation of NSCs to oligodendrocytes. However, the limitation in nerve tissue accessibility to isolate the NSCs as well as their differentiation toward oligodendrocytes is still challenging. Purpose: In the present study, a hybrid polycaprolactone (PCL)-gelatin nanofiber scaffold mimicking the native extracellular matrix and axon morphology to direct the differentiation of bone marrow-derived NSCs to OLCs was introduced. Materials and Methods: In order to achieve a sustained release of T3, this factor was encapsulated within chitosan nanoparticles and chitosan-loaded T3 was incorporated within PCL nanofibers. Polyaniline graphene (PAG) nanocomposite was incorporated within gelatin nanofibers to endow the scaffold with conductive properties, which resemble the conductive behavior of axons. Biodegradation, water contact angle measurements, and scanning electron microscopy (SEM) observations as well as conductivity tests were used to evaluate the properties of the prepared scaffold. The concentration of PAG and T3-loaded chitosan NPs in nanofibers were optimized by examining the proliferation of cultured bone marrow-derived mesenchymal stem cells (BMSCs) on the scaffolds. The differentiation of BMSCs-derived NSCs cultured on the fabricated scaffolds into OLCs was analyzed by evaluating the expression of oligodendrocyte markers using immunofluorescence (ICC), RT-PCR and flowcytometric assays. Results: Incorporating 2% PAG proved to have superior cell support and proliferation while guaranteeing electrical conductivity of 10.8 × 10-5 S/cm. Moreover, the scaffold containing 2% of T3-loaded chitosan NPs was considered to be the most biocompatible samples. Result of ICC, RT-PCR and flow cytometry showed high expression of O4, Olig2, platelet-derived growth factor receptor-alpha (PDGFR-α), O1, myelin/oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP) high expressed but low expression of glial fibrillary acidic protein (GFAP). Conclusion: Considering surface topography, biocompatibility, electrical conductivity and gene expression, the hybrid PCL/gelatin scaffold with the controlled release of T3 may be considered as a promising candidate to be used as an in vitro model to study patient-derived oligodendrocytes by isolating patient's BMSCs in pathological conditions such as diseases or injuries. Moreover, the resulted oligodendrocytes can be used as a desirable source for transplanting in patients.


Assuntos
Materiais Biomiméticos/farmacologia , Células da Medula Óssea/citologia , Diferenciação Celular , Nanofibras/química , Células-Tronco Neurais/citologia , Oligodendroglia/citologia , Tecidos Suporte/química , Compostos de Anilina/química , Animais , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condutividade Elétrica , Gelatina/química , Grafite/química , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/ultraestrutura , Células-Tronco Neurais/metabolismo , Oligodendroglia/efeitos dos fármacos , Poliésteres/química , Ratos , Suínos , Tri-Iodotironina/farmacologia
2.
Exp Eye Res ; 194: 108007, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32194064

RESUMO

Multiple aspects of cornea development, including the innervation of the cornea by trigeminal axons, are sensitive to embryonic levels of thyroid hormone (TH). Although previous work showed that increased TH levels could enhance the rate of axonal extension within the cornea in a thyroxine (T4)-dependent manner, details underlying the stimulatory effect of TH on cornea innervation are unclear. Here, by examining the effects throughout all stages of cornea innervation of the two main THs, triiodothyronine (T3) and T4, we provide a more complete characterization of the stimulatory effects of TH on corneal nerves and begin to unravel the underlying molecular mechanisms. During development, trigeminal axons are initially repelled at the corneal periphery and encircle the cornea in a pericorneal nerve ring prior to advancing into the corneal stroma radially from all along the nerve ring. Overall, exogenous T3 led to pleiotropic effects throughout all stages of cornea innervation, whereas the effects of exogenous T4 was confined to timepoints following completion of the nerve ring. Specifically, exogenous T3 accelerated the formation of the pericorneal nerve ring. By utilizing in vitro neuronal explants studies we demonstrated that T3 acts as a trophic factor to directly stimulate trigeminal nerve growth. Further, exogenous T3 caused disorganized and precocious innervation of the cornea, accompanied by the downregulation of inhibitory Robo receptors that normally act to regulate the timing of nerve advancement into the Slit-expressing corneal tissues. Following nerve ring completion, the growth rate and branching behavior of nerves as they advanced into and through the cornea were found to be stimulated equally by T3 or T4. These stimulatory influences of T3/T4 over nerves likely arose as secondary consequences brought on by TH-mediated modulations to the corneal extracellular matrix. Specifically, we found that the levels of nerve-inhibitory keratan- and chondroitin-sulfate containing proteoglycans and associated sulfation enzymes were dramatically altered in the presence of exogenous T3 or T4. Altogether, these findings uncover new roles for TH on corneal development and shed insight into the mechanistic basis of both T3 and T4 on cornea innervation.


Assuntos
Axônios/efeitos dos fármacos , Córnea/inervação , Desenvolvimento Embrionário/fisiologia , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Animais , Embrião de Galinha , Córnea/efeitos dos fármacos , Córnea/embriologia , Feminino
3.
Life Sci ; 245: 117385, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32014425

RESUMO

AIM: The influence of thyroid hormones on exocrine pancreas function is poorly understood, and limited to the postnatal development period. Here, we evaluated the effects of hypo- and hyperthyroidism on the morphology and enzyme content of this tissue. MAIN METHODS: To induce hypothyroidism male Wistar rats were subjected to a thyroidectomy (Tx) or sham operated (SO). After 40 days, some of the Tx and SO rats were treated with T3 for 7 days. Following euthanization, the pancreas was removed and evaluated for morphology, as well as amylase, lipase and trypsin content, using histological and immunoreactive techniques analyses, respectively. Serum amylase levels were also evaluated. KEY FINDINGS: The pancreatic acinar cells of Tx rats were smaller, exhibited reduced Haematoxyllin stained areas, and contained lower amylase and lipase levels, indicative of low cell activity. Tx rats also presented higher collagen levels, and high trypsin content in pancreatic extracts. Interestingly, T3 administration reversed the observed acinar cell alterations and restored pancreatic enzyme content, by augmenting amylase and lipase and attenuating trypsin levels, but failed to change collagen content. Increased levels of lipase and decreased trypsin were also observed in T3-treated SO rats. SIGNIFICANCE: Thyroid hormones play an important role in acinar cell morphology and function. In the hypothyroid state there is a decrease in pancreatic enzyme levels that is restored with T3 treatment. In addition to participating in insulin sensitivity and glycemic control, THs also modulate enzyme expression and activity in the exocrine pancreas, consequently, delivering metabolic substrates to specific organs and tissues.


Assuntos
Pâncreas Exócrino/patologia , Hormônios Tireóideos/fisiologia , Amilases/sangue , Animais , Western Blotting , Hipertireoidismo/complicações , Hipertireoidismo/patologia , Hipotireoidismo/complicações , Hipotireoidismo/patologia , Masculino , Pâncreas Exócrino/efeitos dos fármacos , Pâncreas Exócrino/fisiopatologia , Ratos , Ratos Wistar , Tireoidectomia , Tireotropina/sangue , Tri-Iodotironina/farmacologia
4.
J Equine Vet Sci ; 86: 102895, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32067668

RESUMO

The effects of two concentrations of triiodothyronine (T3; 0.01 and 1,000 nM) on the osteogenic and chondrogenic differentiation abilities of equine adipose-derived mesenchymal stem cells (AD-MSCs) were evaluated. The osteogenic study evaluated the effect of T3 using alkaline phosphatase activity (ALP) assay; cell viability and density; and formation of mineralized nodules at Days 7, 14, and 21 in culture. The chondrogenic study tested the effect of T3 through ALP assay, mitochondrial metabolism, cell density, and periodic acid-Schiff-positive (PAS+) matrix percentage at Days 7 and 14. In both experiments, analysis of variance was used to compare averages through the Student-Newman-Keuls test. In the osteogenic study, no differences in any variable were detected between groups at Day 7. At Day 14, 0.01 nM T3 reduced cell density and the number of mineralized nodules despite the increase in ALP activity and mitochondrial metabolism (P < .05). ALP activity increased at 1,000 nM T3 concentration (P < .05). At Day 21, 0.01 nM T3 treatment increased ALP activity compared with control treatment (P < .05). At 1,000 nM concentration, T3 reduced mitochondrial metabolism and cell density (P < .05). In the chondrogenic study, the two T3 concentrations increased cell density compared with control treatment at Day 7. At Day 14, higher T3 concentration reduced mitochondrial metabolism, ALP activity, cell density, and PAS+ chondrogenic matrix percentage compared with control treatment (P < .05). Thus, T3 addition to equine AD-MSC cultures has no enhancement effect on osteogenic or chondrogenic differentiation and may, in fact, negatively affect cell density and matrix synthesis depending on hormone concentration and culture time.


Assuntos
Tecido Adiposo , Tri-Iodotironina , Animais , Diferenciação Celular , Células Cultivadas , Cavalos , Células-Tronco , Tri-Iodotironina/farmacologia
5.
Mol Cell Endocrinol ; 500: 110629, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678419

RESUMO

Reproduction and growth are under multifactorial control of neurohormones and peripheral hormones. This study investigated seasonally related effects of GnIH, GnRH, and T3 on the reproductive and growth axis in male goldfish at three stages of gonadal recrudescence. The effects of injection treatments with GnRH, GnIH and/or T3 were examined by measuring serum LH and GH levels, as well as peripheral transcript levels, using a factorial design. As expected, GnRH elevated serum LH and GH levels in a seasonally dependant manner, with maximal elevations of LH in late stages of gonadal recrudescence (Spring) and maximal increases in GH in the regressed gonadal stage (Summer). GnIH injection increased serum LH and GH levels only in fish at the regressed stage but exerted both stimulatory and inhibitory effects on GnRH-induced LH responses depending on season. T3 treatment mainly had stimulatory effects on circulating LH levels and inhibitory effects on serum GH concentrations. In the liver and testes, we observed seasonal differences in thyroid receptors, estrogen receptors, vitellogenin, follicle-stimulating hormone receptor, aromatase and IGF-I transcript levels that were tissue- and sex-specific. Generally, there were no clear correlation between circulating LH and GH levels and peripheral transcript levels, presumably due to time-related response and possible direct interaction of GnRH and GnIH at the level of liver and testis. The results support the hypothesis that GnRH and GnIH are important components of multifactorial mechanisms that work in concert with T3 to regulate reciprocal control of reproduction and growth in goldfish.


Assuntos
Carpa Dourada/fisiologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Neuropeptídeos/administração & dosagem , Tri-Iodotironina/administração & dosagem , Animais , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio do Crescimento/sangue , Fígado/metabolismo , Hormônio Luteinizante/sangue , Masculino , Neuropeptídeos/farmacologia , Especificidade de Órgãos , Reprodução , Testículo/metabolismo , Tri-Iodotironina/farmacologia
6.
Mol Cell Endocrinol ; 503: 110690, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874199

RESUMO

Adiponectin and leptin, important for metabolic regulation, are synthesized and secreted by adipose tissue and are influenced by triiodothyronine (T3) that activates the MAPK/ERK and integrin αVß3 pathways, modulating gene expression. Adipocytes were treated with T3 (10 nM), for 1 h, in the absence or presence of PD98059 (PD) and tetraiodothyroacetic acid (Tetrac), which are pathways inhibitors. The cells were incubated with Adipo Red/Oil Red O reagents, and intracellular lipid accumulation [glycerol and triacylglycerol (TAG)], MTT, 8-hydroxideoxyguanosine (8-OH-dG), and mRNA and protein expression were assessed. T3 increased leptin mRNA and protein expression, and, in contrast, there was a decrease in the Tetrac + T3 group. Adiponectin mRNA expression was not altered by T3, though it had increased its protein expression, which was terminated by inhibitors PD + T3 and Tetrac + T3. However, T3 did not alter PPARγ protein expression, lipid accumulation, TAG, glycerol, and DNA damage, but PD + T3 and Tetrac + T3 reduced these parameters. T3 activated the MAPK/ERK pathway on adipocytes to modulate the adiponectin protein expression and integrin αvß3 to alter the leptin gene expression.


Assuntos
Adipócitos/efeitos dos fármacos , Adiponectina/metabolismo , Leptina/metabolismo , Tri-Iodotironina/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Expressão Gênica/efeitos dos fármacos , Camundongos , Transdução de Sinais/efeitos dos fármacos , Tiroxina/análogos & derivados , Tiroxina/farmacologia , Regulação para Cima/efeitos dos fármacos
7.
Ulus Travma Acil Cerrahi Derg ; 25(6): 545-554, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31701499

RESUMO

BACKGROUND: Sepsis can be defined as a life-threatening organ dysfunction due to a dysregulated host response to infection. In sepsis, the coagulation cascade is activated and the balance shifts to the procoagulant side. Recently, the use of protein C is proposed for the treatment of sepsis. Another therapeutic agent that has been intensively studied is tri-iodothyronine. METHODS: This study aimed to compare the effects of activated protein C and tri-iodothyronine, which are administered at a single dose to sepsis-induced rats at the late phase. Leukocyte, platelet, hemoglobin and antithrombin-III concentrations and histopathological changes in the small intestine, liver and lung were evaluated at 24 hours. RESULTS: Single-dose intraperitoneal recombinant human APC (activated protein C) has a partial curative effect on hematological parameters in the late phase, while it is possible to state that it has significant therapeutic effects on hepatic and intestinal tissues, but more remarkably on the lung tissue. Tri-iodothyronine is also considered to be used for the treatment and has a strong potential to be a therapeutic agent. CONCLUSION: We observed that the T3 hormone has significantly limited and reduced the sepsis-related damage to hepatic and intestinal tissues, but especially the lung tissue. Tri-iodothyronine can be a good alternative to APC, which is partially allowed due to high cost and complication of bleeding in the treatment of sepsis.


Assuntos
Proteína C , Sepse , Tri-Iodotironina , Animais , Modelos Animais de Doenças , Hemoglobinas/análise , Intestinos/efeitos dos fármacos , Intestinos/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Proteína C/farmacologia , Proteína C/uso terapêutico , Ratos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Sepse/tratamento farmacológico , Sepse/fisiopatologia , Tri-Iodotironina/farmacologia , Tri-Iodotironina/uso terapêutico
8.
PLoS One ; 14(10): e0223272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31584962

RESUMO

The nicotinic acetylcholine receptor (nAChR) is an excitatory pentameric ligand-gated ion channel (pLGIC), homologous to the inhibitory γ-aminobutyric acid (GABA) type A receptor targeted by pharmaceuticals and endogenous sedatives. Activation of the GABAA receptor by the neurosteroid allopregnanolone can be inhibited competitively by thyroid hormone (L-3,3',5-triiodothyronine, or T3), but modulation of nAChR by T3 or neurosteroids has not been investigated. Here we show that allopregnanolone inhibits the nAChR from Torpedo californica at micromolar concentrations, as do T3 and the anionic neurosteroid pregnenolone sulfate (PS). We test for the role of protein and ligand charge in mediated receptor inhibition by varying pH in a narrow range around physiological pH. We find that both T3 and PS become less potent with increasing pH, with remarkably similar trends in IC50 when T3 is neutral at pH < 7.3. After deprotonation of T3 (but no additional deprotonation of PS) at pH 7.3, T3 loses potency more slowly with increasing pH than PS. We interpret this result as indicating the negative charge is not required for inhibition but does increase activity. Finally, we show that both T3 and PS affect nAChR channel desensitization, which may implicate a binding site homologous to one that was recently indicated for accelerated desensitization of the GABAA receptor by PS.


Assuntos
Antagonistas Nicotínicos/farmacologia , Pregnenolona/farmacologia , Receptores Nicotínicos/metabolismo , Torpedo/metabolismo , Tri-Iodotironina/farmacologia , Animais , Relação Dose-Resposta a Droga , Antagonistas de Receptores de GABA-A/química , Antagonistas de Receptores de GABA-A/farmacologia , Concentração Inibidora 50 , Cinética , Estrutura Molecular , Antagonistas Nicotínicos/química , Oócitos/metabolismo , Pregnenolona/química , Receptores de GABA-A/metabolismo , Tri-Iodotironina/química
9.
PLoS One ; 14(9): e0221747, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31490950

RESUMO

Multiple sclerosis (MS) is characterized by demyelinated lesions in the central nervous system. Destruction of myelin and secondary damage to axons and neurons leads to significant disability, particularly in people with progressive MS. Accumulating evidence suggests that the potential for myelin repair exists in MS, although for unclear reasons this process fails. The cells responsible for producing myelin, the oligodendrocytes, and their progenitors, oligodendrocyte precursor cells (OPCs), have been identified at the site of lesions, even in adults. Their presence suggests the possibility that endogenous remyelination without transplantation of donor stem cells may be a mechanism for myelin repair in MS. Strategies to develop novel therapies have focused on induction of signaling pathways that stimulate OPCs to mature into myelin-producing oligodendrocytes that could then possibly remyelinate lesions. We have been investigating pharmacological approaches to enhance OPC differentiation, and have identified that the combination of two agents, triiodothyronine (T3) and quetiapine, leads to an additive effect on OPC differentiation and consequent myelin production via both overlapping and distinct signaling pathways. While the ultimate production of myelin requires cholesterol biosynthesis, we identified that quetiapine enhances gene expression in this pathway more potently than T3. Two blockers of cholesterol production, betulin and simvastatin, reduced OPC differentiation into myelin producing oligodendrocytes. Elucidating the nature of agents that lead to complementary and additive effects on oligodendrocyte differentiation and myelin production may pave the way for more efficient induction of remyelination in people with MS.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Colesterol/biossíntese , Células Precursoras de Oligodendrócitos/citologia , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Fumarato de Quetiapina/farmacologia , Tri-Iodotironina/farmacologia , Animais , Sinergismo Farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Básica da Mielina/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sinvastatina/farmacologia , Triterpenos/farmacologia
10.
J Pharmacol Exp Ther ; 371(1): 88-94, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31300610

RESUMO

Vascular dysfunction associated with hypertension comprises hypercontractility and impaired vasodilation. We have previously demonstrated that triiodothyronine (T3), the active form of thyroid hormone, has vasodilatory effects acting through rapid onset mechanisms. In the present study, we examined whether T3 mitigates vascular dysfunction associated with hypertension. To test the direct effects of T3 in hypertensive vessels, aortas from female Dahl salt-sensitive (Dahl SS) rats fed a high-salt diet (8% NaCl, HS group) and their age-matched controls fed a standard low-salt diet (0.3% NaCl, LS group) for 16 weeks were isolated and used in ex vivo vascular reactivity studies. We confirmed that the HS group exhibited a higher systolic blood pressure in comparison with the control LS group and displayed aortic remodeling. Aortas from both groups were pretreated with T3 (0.1 µM) for 30 minutes at 37°C in a 5% CO2 incubator before functional vascular studies. T3 treatment significantly attenuated hypercontractility and improved impaired endothelium-dependent vasodilation in aortas from the HS group. These vascular improvements in response to T3 were accompanied by increased phosphorylation of vasodilator-stimulated phosphoprotein (VASP) at serine 239, a vasodilatory factor of the cGMP-dependent protein kinase (PKG)/VASP signaling pathway in vascular smooth muscle cells. Moreover, increased production of reactive oxygen species in aortas from the HS group were significantly reduced by T3, suggesting a potential antioxidant effect of T3 in the vasculature. These results demonstrate that T3 can mitigate hypertension-related vascular dysfunction through the VASP signaling pathway and by reducing vascular ROS production. SIGNIFICANCE STATEMENT: This study demonstrates that triiodothyronine (T3) directly acts on vascular tone and has a beneficial effect in hypertension-induced vascular dysfunction. T3 augmented vasodilation and diminished vasoconstriction in blood vessels from hypertensive rats in association with activation of the protein kinase G/vasodilator-stimulated phosphoprotein signaling pathway that activates vascular relaxation and exerted an antioxidant effect. Collectively, these results show that T3 is a potential vasoprotective agent with rapid action on hypertension-related vascular dysfunction.


Assuntos
Anti-Hipertensivos/farmacologia , Aorta/efeitos dos fármacos , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Hipertensão/tratamento farmacológico , Transdução de Sinais , Tri-Iodotironina/farmacologia , Animais , Anti-Hipertensivos/uso terapêutico , Aorta/metabolismo , Aorta/fisiopatologia , Feminino , Fosforilação , Ratos , Ratos Endogâmicos Dahl , Tri-Iodotironina/uso terapêutico , Vasodilatação
11.
Artigo em Inglês | MEDLINE | ID: mdl-31181291

RESUMO

Thyroid hormones (THs) play an important role in early stages development of fish species. Manual elevation of THs in the embryos improves viability and hatching success. However, the impacts of endocrine disrupting chemicals on THs-treated embryos are unclear. This study investigated the effect of triiodothyronine (T3) to mitigate toxic effects of diazinon in the endangered Persian sturgeon (Acipenser persicus) eggs and embryos. Fertilized eggs were exposed to nominal concentrations of 0, 2, 4, 6, and 8 mg/L diazinon and the 96 h LC50 value was calculated at 3.5 mg/L. Eggs were then treated with exogenous T3 (1 ng/mL: LT3, and 10 ng/mL: HT3) and exposed to 3.5 mg/L diazinon (DLT3 and DHT3). Total THs concentrations, levels of cortisol, and expression of the igf-II gene were measured during embryogenesis. All the measured endpoints were significantly different between treatments or stages of incubation. Generally, despite insignificance in some cases, higher levels of T3 and Thyroxin (T4) were observed in T3-treated embryos regardless of the presence of diazinon. Cortisol was high in unfertilized eggs which reduced after fertilization. The igf-II gene up-regulated quickly after fertilization; was higher in T3-treated embryos. Exposure of eggs to diazinon reduced the levels of T3, T4, and igf-II gene expression, which corresponded to the lowest hatching. We concluded that exogenous T3 improves embryos development in A. persicus, which is a promising application for conservation strategies. Our study suggests that treating embryos with 10 ng/L T3 is a suitable way to overcome problems of incubation in diazinon-polluted water sources.


Assuntos
Diazinon/antagonistas & inibidores , Diazinon/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Peixes/embriologia , Tri-Iodotironina/farmacologia , Zigoto/efeitos dos fármacos , Animais , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário , Disruptores Endócrinos/toxicidade , Poluentes Químicos da Água/toxicidade , Zigoto/crescimento & desenvolvimento
12.
Thorax ; 74(8): 749-760, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31182654

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a fatal ageing-related disease linked to mitochondrial dysfunction. The present study aimed to determine whether peroxisome proliferator activated receptor gamma co-activator 1-alpha (PPARGC1A, encoding PGC1α), a master regulator of mitochondrial biogenesis, is diminished in IPF and controls pathologic fibroblast activation. Primary human IPF, control lung fibroblasts and fibroblasts sorted from bleomycin-injured mice were used to evaluate the expression and function of PGC1α. In vitro PGC1α manipulation was performed by small interfering RNA knockdown or overexpression. Fibroblast activation was assessed by quantitative PCR, Western blotting, matrix deposition, secreted cytokine array, immunofluorescence and traction force microscopy. Mitochondrial function was assessed by Seahorse analyzer and mitochondria mass and number by flow cytometry, mitochondrial DNA quantification and transmission electron microscopy (TEM). We found that PGC1α levels are stably repressed in IPF fibroblasts. After bleomycin injury in young mice, PGC1α expression drops transiently but then increases prior to fibrosis resolution. In contrast, PGC1α expression fails to recover in aged mice with persistent fibrosis. PGC1α knockdown alone in normal human lung fibroblasts reduces mitochondrial mass and function while enhancing contractile and matrix synthetic fibroblast activation, senescence-related gene expression and soluble profibrotic and prosenescence signalling. Re-expression of PGC1α in IPF fibroblasts ameliorates all of these pathological cellular functions. Pharmacological treatment of IPF fibroblasts with rosiglitazone, but not thyroid hormone, elevated PGC1α expression and attenuated fibroblast activation. The sustained repression of PGC1α and beneficial effects of its rescue in IPF fibroblasts identifies PGC1α as an important regulator of the fibroblast's pathological state in IPF.


Assuntos
Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Actinas/genética , Animais , Bleomicina , Linhagem Celular , Senescência Celular/genética , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Fibronectinas/genética , Fibronectinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Hipoglicemiantes/farmacologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Camundongos , NAD/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Cultura Primária de Células , RNA Interferente Pequeno , Rosiglitazona/farmacologia , Transdução de Sinais/genética , Tri-Iodotironina/farmacologia , beta-Galactosidase/genética
13.
Theriogenology ; 133: 1-9, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31051388

RESUMO

The experiment was designed to study the effects of Thyroid hormone (T3) on the proliferation and differentiation of newborn calf Sertoli cells (SCs) to provide a theoretical and practical basis for increased testicular semen production. In this experiment, the cck8 method was used to detect the effects of different concentrations of T3 on the proliferation rate of newborn calf SCs. qPCR and Western Blot methods were used to explore the effects of T3 on the proliferation and differentiation of calves SCs and whether T3 through Wnt/ß-catenin and PI3K/Akt pathways can regulate the proliferation and differentiation of SCs. We found that dosage (T3) and time correlated with proliferation inhibition of SC. T3 inhibited the proliferation of SC by down-regulating cyclinD1, upregulating p21Cip, p27Kip1, and other cell-cycle factors. By up-regulating AR and down-regulating KRT-18, T3 promoted the maturated differentiation of SC. T3 could not affect the expression of ß-catenin in SC of newborn calf, indicating that T3 may not regulate SCs proliferation through the Wnt pathway. T3 also negatively regulated the gene expression and protein levels of some genes in the PI3K/Akt signaling pathway. We concluded that T3 inhibited newborn calf SCs proliferation through the PI3K/Akt signaling pathway and possibly promoted their differentiation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células de Sertoli/metabolismo , Tri-Iodotironina/farmacologia , Animais , Animais Recém-Nascidos/metabolismo , Bovinos , Células Cultivadas , Masculino , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células de Sertoli/citologia , Transdução de Sinais/efeitos dos fármacos , Tri-Iodotironina/metabolismo , Tri-Iodotironina/fisiologia
14.
Fish Physiol Biochem ; 45(4): 1233-1244, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31115741

RESUMO

Flatfish pigmentation is a complex process, affected by environmental factors including light, nutrients, and hormones. Of those, the thyroid hormone has been reported to increase the albinism rate of Japanese flounder (Paralichthys olivaceus). However, the underlying mechanism remains unclear. In the present study, triiodothyronine (T3), thyroxine, and thiourea were introduced into P. olivaceus larvae from 16 to 57 days after hatching (DAH). By comparison of albinism rate, T3 treatment and control larvae of 42 DAH were chosen for mRNA and miRNA high-throughput sequencing analyses. A total of 337 miRNAs were identified via miRNA-seq, and 12 miRNAs exhibited significantly differential expression patterns in D42_T3 versus D42_Con (TPM > 10, fold change ≥ 1.5 or ≤ 0.67 and q ≤ 0.05). These differentially expressed miRNAs targeted 3658 putative genes, which further enriched to 10 GO terms (q < 0.05). RNA-seq identified 146 differentially expressed genes (DEGs) in D42_T3 versus D42_Con (|log2 fold change| > 1 and q < 0.005), including pigmentation-related genes such as the receptor tyrosine-protein kinase erbB-3, pro-opiomelanocortin A, and melanotransferrin, and the growth-related gene somatotropin. These DEGs were significantly enriched to 15 GO terms and 8 KEGG pathways (q < 0.05), which included several sugar metabolic pathways (glycolysis/gluconeogenesis and the pentose phosphate pathway). Integrated analysis revealed that 26 overlapping genes between DEGs and mRNAs were targeted by miRNAs. Furthermore, seven mRNA-miRNA pairs exhibited reversed regulation patterns. This provides important clues to understand the role of thyroid hormones in flatfish pigmentation.


Assuntos
Linguado/genética , Larva/efeitos dos fármacos , Tioureia/farmacologia , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Animais , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Larva/genética , MicroRNAs/genética , Pigmentação/efeitos dos fármacos , RNA Mensageiro/genética , RNA-Seq
15.
Endocrinology ; 160(10): 2243-2256, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31095291

RESUMO

Traumatic brain injury (TBI) is associated with disruption of cerebral blood flow leading to localized brain hypoxia. Thyroid hormone (TH) treatment, administered shortly after injury, has been shown to promote neural protection in rodent TBI models. The mechanism of TH protection, however, is not established. We used mouse primary cortical neurons to investigate the effectiveness and possible pathways of T3-promoted cell survival after exposure to hypoxic injury. Cultured primary cortical neurons were exposed to hypoxia (0.2% oxygen) for 7 hours with or without T3 (5 nM). T3 treatment enhanced DNA 5-hydroxymethylcytosine levels and attenuated the hypoxia-induced increase in DNA 5-methylcytosine (5-mc). In the presence of T3, mRNA expression of Tet family genes was increased and DNA methyltransferase (Dnmt) 3a and Dnmt3b were downregulated, compared with conditions in the absence of T3. These T3-induced changes decreased hypoxia-induced DNA de novo methylation, which reduced hypoxia-induced neuronal damage and apoptosis. We used RNA sequencing to characterize T3-regulated genes in cortical neurons under hypoxic conditions and identified 22 genes that were upregulated and 15 genes that were downregulated. Krüppel-like factor 9 (KLF9), a multifunctional transcription factor that plays a key role in central nervous system development, was highly upregulated by T3 treatment in hypoxic conditions. Knockdown of the KLF9 gene resulted in early apoptosis and abolished the beneficial role of T3 in neuronal survival. KLF9 mediates, in part, the neuronal protective role of T3. T3 treatment reduces hypoxic damage, although pathways that reduce DNA methylation and apoptosis remain to be elucidated.


Assuntos
Córtex Cerebral/citologia , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Oxigênio/farmacologia , Tri-Iodotironina/farmacologia , 5-Metilcitosina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Metilação de DNA , Regulação da Expressão Gênica/efeitos dos fármacos , Neurônios/fisiologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transcriptoma
16.
Arch. endocrinol. metab. (Online) ; 63(2): 142-147, Mar.-Apr. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1001213

RESUMO

ABSTRACT Objective: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway Materials and methods: The cell line was treated with T3 at a physiological dose (10−9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. Results: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. Conclusion: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.


Assuntos
Humanos , Feminino , Tri-Iodotironina/genética , Neoplasias da Mama/genética , Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Fator de Crescimento Transformador alfa/genética , Sistema de Sinalização das MAP Quinases/genética , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia , Proto-Oncogenes/genética , Neoplasias da Mama/metabolismo , RNA Mensageiro/genética , Adenocarcinoma/metabolismo , Fator de Crescimento Transformador alfa/efeitos dos fármacos , Fator de Crescimento Transformador alfa/metabolismo , Linhagem Celular Tumoral/metabolismo , Células MCF-7/metabolismo
17.
Arch Endocrinol Metab ; 63(2): 142-147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30916164

RESUMO

OBJECTIVE: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway. MATERIALS AND METHODS: The cell line was treated with T3 at a physiological dose (10-9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. RESULTS: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. CONCLUSION: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases/genética , Fator de Crescimento Transformador alfa/genética , Tri-Iodotironina/genética , Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral/metabolismo , Feminino , Humanos , Células MCF-7/metabolismo , Proto-Oncogenes/genética , RNA Mensageiro/genética , Fator de Crescimento Transformador alfa/efeitos dos fármacos , Fator de Crescimento Transformador alfa/metabolismo , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia
18.
Horm Behav ; 110: 90-97, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30826308

RESUMO

Seasonal changes in day length enhance and suppress immune function in a trait-specific manner. In Siberian hamsters (Phodopus sungorus) winter-like short days (SDs) increase blood leukocyte concentrations and adaptive T cell dependent immune responses, but attenuate innate inflammatory responses to simulated infections. Thyroid hormone (TH) signaling also changes seasonally and has been implicated in modulation of the reproductive axis by day length. Immunologically, TH administration in long days (LD) enhances adaptive immune responses in male Siberian hamsters, mimicking effects of SDs. This experiment tested the hypothesis that T3 is also sufficient to mimic the effects of SD on innate immune responses. Adult male hamsters housed in LDs were pretreated with triiodothyronine (T3; 1 µg, s.c.) or saline (VEH) daily for 6 weeks; additional positive controls were housed in SD and received VEH, after which cytokine, behavioral, and physiological responses to simulated bacterial infection (lipopolysaccharide; LPS) were evaluated. SD pretreatment inhibited proinflammatory cytokine mRNA expression (i.e. interleukin 1ß, nuclear factor kappa-light-chain-enhancer of activated B cells). In addition, the magnitude and persistence of anorexic and cachectic responses to LPS were also lower in SD hamsters, and LPS-induced inhibition of nest building behavior was absent in SD. T3 treatments failed to affect behavioral (food intake, nest building) or somatic (body mass) responses to LPS in LD hamsters, but one CNS cytokine response to LPS (e.g., hypothalamic TNFα) was augmented by T3. Together these data implicate thyroid hormone signaling in select aspects of innate immune responses to seasonal changes in day length.


Assuntos
Comportamento Animal/efeitos dos fármacos , Citocinas/metabolismo , Phodopus , Síndrome de Resposta Inflamatória Sistêmica/patologia , Tri-Iodotironina/farmacologia , Animais , Anorexia/induzido quimicamente , Anorexia/metabolismo , Anorexia/patologia , Peso Corporal/fisiologia , Cricetinae , Modelos Animais de Doenças , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Comportamento de Doença/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Infecções/induzido quimicamente , Infecções/metabolismo , Infecções/patologia , Lipopolissacarídeos , Masculino , Phodopus/metabolismo , Fotoperíodo , Reprodução/efeitos dos fármacos , Estações do Ano , Síndrome de Resposta Inflamatória Sistêmica/induzido quimicamente , Síndrome de Resposta Inflamatória Sistêmica/metabolismo , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia
19.
Ecotoxicol Environ Saf ; 174: 353-362, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30849655

RESUMO

The liver is one of the major targets of hormones, including thyroid hormones (THs), and many industrial chemicals, such as endocrine-disrupting chemicals. Those compounds may permeate the placenta barrier and pose a risk for embryonic development. Therefore, it is necessary to assess the toxic effects of those kind of industrial chemicals during liver development. In this study, to mimic liver specification in vitro, we differentiated human embryonic stem cells (ESCs) into functional hepatocyte-like cells. We performed this differentiation process in presence of two THs, triiodothyronine (T3) and thyroxine (T4), with the purpose of identifying biomarkers for toxicity screening. TH exposure (3, 30 and 300 nM) yielded to hepatocytes with impaired glycogen storage ability and abnormal lipid droplets' accumulation. Global gene expression analysis by RNA-seq identified a number of genes responsible for hepatic differentiation and function which were affected by 30 nM T3 and T4. Those differentially expressed genes were used to assess the potential developmental liver toxicity of two famous environmental pollutants, 2, 2, 4, 4-tetrabromodiphenyl ether (BDE-47) and decabromodiphenyl ether (BDE-209), at 10 nM to 1 µM treatments. Our findings demonstrate that BDE-47 and BDE-209, dysregulated pathways such as "chemical carcinogenesis", "steroid hormone biosynthesis" and "drug metabolism-cytochrome P450". Moreover, we were able to identify a set of 17 biomarkers, very useful to predict the potential developmental hepatotoxicity of industrial chemicals.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Hepatócitos/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Modelos Biológicos , Animais , Diferenciação Celular/genética , Doença Hepática Induzida por Substâncias e Drogas/embriologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Feminino , Éteres Difenil Halogenados/toxicidade , Humanos , Gravidez , Tiroxina/farmacologia , Transcriptoma/efeitos dos fármacos , Tri-Iodotironina/farmacologia
20.
Cell Physiol Biochem ; 52(2): 354-367, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816679

RESUMO

BACKGROUND/AIMS: Although a cross-talk between immune and endocrine systems has been well established, the precise pathways by which these signals co-regulate pro- and antiinflammatory responses on antigen-presenting cells remain poorly understood. In this work we investigated the mechanisms by which triiodothyronine (T3) controls T cell activity via dendritic cell (DC) modulation. METHODS: DCs from wild-type (WT) and IL-6-deficient mice were pulsed with T3. Cytokine production and programmed death protein ligands (PD-L) 1 and 2 expression were assayed by flow cytometry and ELISA. Interferon-regulatory factor-4 (IRF4) expression was evaluated by RT-qPCR and flow cytometry. The ability of DCs to stimulate allogenic splenocytes was assessed in a mixed lymphocyte reaction and the different profile markers were analyzed by flow cytometry and ELISA. For in vivo experiments, DCs treated with ovalbumin and T3 were injected into OTII mice. Proliferation, cytokine production, frequency of FoxP3+ regulatory T (Treg) cells and PD-1+ cells were determined by MTT assay, ELISA and flow cytometry, respectively. RESULTS: T3 endows DCs with pro-inflammatory potential capable of generating IL-17-dominant responses and down-modulating expression of PD-L1 and 2. T3-stimulated WT-DCs increased the proportion of IL-17-producing splenocytes, an effect which was eliminated when splenocytes were incubated with T3-treated DCs derived from IL-6-deficient mice. Enhanced IL-17 expression was recorded in both, CD4- and CD4+ populations and involved the IRF-4 pathway. Particularly, γδ-T cells but not natural killer (NK), NKT, B lymphocytes nor CD8+ T cells were the major source of IL-17-production from CD4- cells. Moreover, T3-conditioned DCs promoted a decrease of the FoxP3+ Treg population. Furthermore, T3 down-modulated PD-1 expression on CD4- cells thereby limiting inhibitory signals driven by this co-inhibitory pathway. Thus, T3 acts at the DC level to drive proinflammatory responses in vitro. Accordingly, we found that T3 induces IL-17 and IFNγ-dominant antigen-specific responses in vivo. CONCLUSION: These results emphasize the relevance of T3 as an additional immune-endocrine checkpoint and a novel therapeutic target to modulate IL-17-mediated pro-inflammatory responses.


Assuntos
Células Dendríticas/imunologia , Interleucina-17/imunologia , Transdução de Sinais/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Dendríticas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/imunologia , Interleucina-17/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Camundongos , Camundongos Knockout , Proteína 2 Ligante de Morte Celular Programada 1/genética , Proteína 2 Ligante de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Transdução de Sinais/imunologia
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