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Neuroligins are synaptic cell adhesion proteins with a role in synaptic function, implicated in neurodevelopmental disorders. The autism spectrum disorder-associated substitution Arg451Cys (R451C) in NLGN3 promotes a partial misfolding of the extracellular domain of the protein leading to retention in the endoplasmic reticulum (ER) and the induction of the unfolded protein response (UPR). The reduced trafficking of R451C NLGN3 to the cell surface leads to altered synaptic function and social behavior. A screening in HEK-293 cells overexpressing NLGN3 of 2662 compounds (FDA-approved small molecule drug library), led to the identification of several glucocorticoids such as alclometasone dipropionate, desonide, prednisolone sodium phosphate, and dexamethasone (DEX), with the ability to favor the exit of full-length R451C NLGN3 from the ER. DEX improved the stability of R451C NLGN3 and trafficking to the cell surface, reduced the activation of the UPR, and increased the formation of artificial synapses between HEK-293 and hippocampal primary neurons. The effect of DEX was validated on a novel model system represented by neural stem progenitor cells and differentiated neurons derived from the R451C NLGN3 knock-in mouse, expressing the endogenous protein. This work shows a potential rescue strategy for an autism-linked mutation affecting cell surface trafficking of a synaptic protein.
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Transtorno do Espectro Autista , Animais , Humanos , Camundongos , Transtorno do Espectro Autista/genética , Glucocorticoides , Células HEK293 , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Sinapses/metabolismoRESUMO
Glucocorticoid use may cause elevated intraocular pressure, leading to the development of glucocorticoid-induced glaucoma (GIG). However, the mechanism of GIG development remains incompletely understood. In this study, we subjected primary human trabecular meshwork cells (TMCs) and mice to dexamethasone treatment to mimic glucocorticoid exposure. The myofibroblast transdifferentiation of TMCs was observed in cellular and mouse models, as well as in human trabecular mesh specimens. This was demonstrated by the cytoskeletal reorganization, alterations in cell morphology, heightened transdifferentiation markers, increased extracellular matrix deposition, and cellular dysfunction. Knockdown of Rho guanine nucleotide exchange factor 26 (ARHGEF26) expression ameliorated dexamethasone-induced changes in cell morphology and upregulation of myofibroblast markers, reversed dysfunction and extracellular matrix deposition in TMCs, and prevented the development of dexamethasone-induced intraocular hypertension. And, this process may be related to the TGF-ß pathway. In conclusion, glucocorticoids induced the myofibroblast transdifferentiation in TMCs, which played a crucial role in the pathogenesis of GIG. Inhibition of ARHGEF26 expression protected TMCs by reversing myofibroblast transdifferentiation. This study demonstrated the potential of reversing the myofibroblast transdifferentiation of TMCs as a new target for treating GIG.
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Transdiferenciação Celular , Dexametasona , Glaucoma , Miofibroblastos , Fatores de Troca de Nucleotídeo Guanina Rho , Malha Trabecular , Dexametasona/farmacologia , Malha Trabecular/efeitos dos fármacos , Malha Trabecular/metabolismo , Malha Trabecular/citologia , Transdiferenciação Celular/efeitos dos fármacos , Animais , Humanos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Miofibroblastos/citologia , Camundongos , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Glaucoma/patologia , Glaucoma/metabolismo , Células Cultivadas , Glucocorticoides/farmacologia , Camundongos Endogâmicos C57BL , MasculinoRESUMO
Dexamethasone (dex) is a glucocorticoid that is a mainstay for the treatment of inflammatory pathologies, including immunotherapy-associated toxicities, yet the specific impact of dex on the activity of CAR T cells is not fully understood. We assessed whether dex treatment given ex vivo or as an adjuvant in vivo with CAR T cells impacted the phenotype or function of CAR T cells. We demonstrated that CAR T cell expansion and function were not inhibited by dex. We confirmed this observation using multiple CAR constructs and tumor models, suggesting that this is a general phenomenon. Moreover, we determined that dex upregulated interleukin-7 receptor α on CAR T cells and increased the expression of genes involved in activation, migration, and persistence when supplemented ex vivo. Direct delivery of dex and IL-7 into tumor-bearing mice resulted in increased persistence of adoptively transferred CAR T cells and complete tumor regression. Overall, our studies provide insight into the use of dex to enhance CAR T cell therapy and represent potential novel strategies for augmenting CAR T cell function during production as well as following infusion into patients.
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Neoplasias , Receptores de Antígenos Quiméricos , Receptores de Interleucina-7 , Humanos , Animais , Camundongos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Imunoterapia Adotiva/métodos , Neoplasias/patologia , Linfócitos T , Dexametasona/farmacologiaRESUMO
Human testicular peritubular cells (HTPCs) are smooth muscle cells, which in the testis form a small compartment surrounding the seminiferous tubules. Contractions of HTPCs are responsible for sperm transport, HTPCs contribute to spermatogenesis, have immunological roles and are a site of glucocorticoid receptor expression. Importantly, HTPCs maintain their characteristics in vitro, and thus can serve as an experimental window into the male gonad. Previously we reported consequences of 3-day treatment with Dexamethasone (Dex), a synthetic glucocorticoid and multi-purpose anti-inflammatory drug. However, as glucocorticoid therapies in man often last longer, we now studied consequences of a prolonged 7-day exposure to 1 µM Dex. Combining live cell imaging with quantative proteomics of samples taken from men, we confirmed our recent findings but more importantly, found numerous novel proteomic alterations induced by prolonged Dex treatment. The comparison of the 7-day treatment with the 3-day treatment dataset revealed that extracellular matrix- and focal adhesion-related proteins become more prominent after 7 days of treatment. In contrast, extended stimulation is, for example, associated with a decrease of proteins related to cholesterol and steroid metabolism. Our dataset, which describes phenotypic and proteomic alterations, is a valuable resource for further research projects investigating effects of Dex on human testicular cells.
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Dexametasona , Proteoma , Humanos , Masculino , Dexametasona/farmacologia , Proteoma/efeitos dos fármacos , Proteoma/metabolismo , Proteoma/análise , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/citologia , Proteômica/métodos , Fenótipo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Células Cultivadas , Glucocorticoides/farmacologiaRESUMO
Given the widespread application of glucocorticoids in ophthalmology, the associated elevation of intraocular pressure (IOP) has long been a vexing concern for clinicians, yet the underlying mechanisms remain inconclusive. Much of the discussion focuses on the extracellular matrix (ECM) of trabecular meshwork (TM). It is widely agreed that glucocorticoids impact the expression of matrix metalloproteinases (MMPs), leading to ECM deposition. Since Zn2+ is vital for MMPs, we explored its role in ECM alterations induced by dexamethasone (DEX). Our study revealed that in human TM cells treated with DEX, the level of intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. This correlated with changes in several Zrt-, Irt-related proteins (ZIPs) and metallothionein. ZIP8 knockdown impaired extracellular Zn2+ uptake, but Zn2+ chelation did not affect ZIP8 expression. Resembling DEX's effects, chelation of Zn2+ decreased MMP2 expression, increased the deposition of ECM proteins, and induced structural disarray of ECM. Conversely, supplementation of exogenous Zn2+ in DEX-treated cells ameliorated these outcomes. Notably, dietary zinc supplementation in mice significantly reduced DEX-induced IOP elevation and collagen content in TM, thereby rescuing the visual function of the mice. These findings underscore zinc's pivotal role in ECM regulation, providing a novel perspective on the pathogenesis of glaucoma.NEW & NOTEWORTHY Our study explores zinc's pivotal role in mitigating extracellular matrix dysregulation in the trabecular meshwork and glucocorticoid-induced ocular hypertension. We found that in human trabecular meshwork cells treated with dexamethasone, intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. Zinc supplementation rescues visual function by modulating extracellular matrix proteins and lowering intraocular pressure, offering a direction for further exploration in glaucoma management.
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Glaucoma , Malha Trabecular , Camundongos , Humanos , Animais , Malha Trabecular/metabolismo , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Glaucoma/patologia , Pressão Intraocular , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Metaloproteinases da Matriz/metabolismo , Zinco/metabolismo , Células CultivadasRESUMO
Studies have shown that adoptive transfer of myeloid-derived suppressor cells (MDSCs) can alleviate various inflammatory diseases, including glomerulonephritis, but the long-term effects of the transferred MDSCs are still unclear. In addition, although glucocorticoids exert immunosuppressive effects on inflammatory diseases by inducing the expansion of MDSCs, the impact of glucocorticoids on the immunosuppressive function of MDSCs and their molecular mechanisms are unclear. In this study, we found that adoptive transfer of MDSCs to doxorubicin-induced focal segmental glomerulosclerosis (FSGS) mice for eight consecutive weeks led to an increase in serum creatinine and proteinuria and aggravation of renal interstitial fibrosis. Similarly, 8 weeks of high-dose dexamethasone administration exacerbated renal interstitial injury and interstitial fibrosis in doxorubicin-induced mice, manifested as an increase in serum creatinine and proteinuria, collagen deposition and α-SMA expression. On this basis, we found that dexamethasone could enhance MDSC expression and secretion of the fibrosis-related cytokines TGF-ß and IL-10. Mechanistically, we revealed that dexamethasone promotes the expression of immunoglobulin-like transcription factor 4 (ILT4), which enhances the T-cell inhibitory function of MDSCs and promotes the activation of STAT6, thereby strengthening the expression and secretion of TGF-ß and IL-10. Knocking down ILT4 alleviated renal fibrosis caused by adoptive transfer of MDSCs. Therefore, our findings demonstrate that the role and mechanism of dexamethasone mediate the expression and secretion of TGF-ß and IL-10 in MDSCs by promoting the expression of ILT4, thereby leading to renal fibrosis.
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Dexametasona , Fibrose , Células Supressoras Mieloides , Animais , Dexametasona/farmacologia , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/efeitos dos fármacos , Camundongos , Rim/patologia , Rim/metabolismo , Rim/efeitos dos fármacos , Masculino , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacologia , Camundongos Endogâmicos C57BL , Glomerulosclerose Segmentar e Focal/induzido quimicamente , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Transferência Adotiva , Modelos Animais de Doenças , Regulação para Cima/efeitos dos fármacos , Interleucina-10/metabolismo , Interleucina-10/genética , Fator de Crescimento Transformador beta/metabolismoRESUMO
Older adults are vulnerable to glucocorticoid-induced muscle atrophy and weakness, with sex potentially influencing their susceptibility to those effects. Aerobic exercise can reduce glucocorticoid-induced muscle atrophy in young rodents. However, it is unknown whether aerobic exercise can prevent glucocorticoid myopathy in aged muscle. The objectives of this study were to define the extent to which sex influences the development of glucocorticoid myopathy in aged muscle, and to determine the extent to which aerobic exercise training protects against myopathy development. Twenty-four-month-old female (n = 30) and male (n = 33) mice were randomized to either sedentary or aerobic exercise groups. Within their respective groups, mice were randomized to either daily treatment with dexamethasone (DEX) or saline. Upon completing treatments, the contractile properties of the triceps surae complex were assessed in situ. DEX marginally lowered muscle mass and soluble protein content in both sexes, which was attenuated by aerobic exercise only in females. DEX increased sub-tetanic force and rate of force development only in females, which was not influenced by aerobic exercise. Muscle fatigue was higher in both sexes following DEX, but aerobic exercise prevented fatigue induction only in females. The sex-specific differences to muscle function in response to DEX treatment coincided with sex-specific changes to the content of proteins related to calcium handling, mitochondrial quality control, reactive oxygen species production, and glucocorticoid receptor in muscle. These findings define several important sexually dimorphic changes to aged skeletal muscle physiology in response to glucocorticoid treatment and define the capacity of short-term aerobic exercise to protect against those changes. KEY POINTS: There are sexually dimorphic effects of glucocorticoids on aged skeletal muscle physiology. Glucocorticoid-induced changes to aged muscle contractile properties coincide with sex-specific differences in the content of calcium handling proteins. Aerobic exercise prevents glucocorticoid-induced fatigue only in aged females and coincides with differences in the content of mitochondrial quality control proteins and glucocorticoid receptors.
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Cyst nematodes co-opt plant developmental programs for the establishment of a permanent feeding site called a syncytium in plant roots. In recent years, the role of plant developmental genes in syncytium formation has gained much attention. One main obstacle in studying the function of development-related genes in syncytium formation is that mutation or ectopic expression of such genes can cause pleiotropic phenotypes, making it difficult to interpret nematode-related phenotypes or, in some cases, impossible to carry out infection assays due to aberrant root development. Here, we tested three commonly used inducible gene expression systems for their application in beet cyst nematode infection assays of the model plant Arabidopsis thaliana. We found that even a low amount of ethanol diminished nematode development, deeming the ethanol-based system unsuitable for use in cyst nematode infection assays, whereas treatment with estradiol or dexamethasone did not negatively affect cyst nematode viability. Dose and time course responses showed that in both systems, a relatively low dose of inducer (1 µM) is sufficient to induce high transgene expression within 24 h of treatment. Transgene expression peaked at 3 to 5 days post-induction and began to decline thereafter, providing a perfect window for inducible transgenes to interfere with syncytium establishment while minimizing any adverse effects on root development. These results indicate that both estradiol- and dexamethasone-based inducible gene expression systems are suitable for cyst nematode infection assays. The employment of such systems provides a powerful tool to investigate the function of essential plant developmental genes in syncytium formation. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Chronic and excessive glucocorticoid (GC) exposure can cause Cushing's syndrome, resulting in fat accumulation in selected body areas. Particularly in the brown adipose tissue (BAT), GC acts negatively, resulting in whitening of the tissue. We hypothesized that dysregulation of microRNAs by GC could be an additional mechanism to explain its negative actions in BAT. Male Wistar rats were divided into two groups: (1) Control sham and (2) GC group that was administered dexamethasone 6.25 mg/200 µL via osmotic pump implantation over 28 days. After this period, the animals were euthanized and BAT tissue was properly stored. Human fat cells treated with dexamethasone were used to translate the experimental results found in animals to human biology. GC-treated rat BAT presented with large lipid droplets, severely impaired thermogenic activation, and reduced glucose uptake measured by 18F-FDG PET/CT. GC exposure induced a reduction in the mitochondrial OXPHOS system and oxygen consumption. MicroRNA profiling of BAT revealed five top-regulated microRNAs and among them miR-21-5p was the most significantly upregulated in GC-treated rats compared to the control group. Although upregulation of miR-21-5p in the tissue, differentiated primary brown adipocytes from GC-treated rats had decreased miR-21-5p levels compared to the control group. To translate these results to the clinic, human brown adipocytes were treated with dexamethasone and miR-21-5p inhibitor. In human brown cells, inhibition of miR-21-5p increased brown adipocyte differentiation and prevented GC-induced glucose uptake, resulting in a lower glycolysis rate. In conclusion, high-dose GC therapy significantly impacts brown adipose tissue function, with a notable association between glucose uptake and miR-21-5p.
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INTRODUCTION: Purportedly, the progression of multiple sclerosis (MS) occurs when neurodegenerative processes due to derangement of axonal bioenergetics take over the autoimmune response. However, a clear picture of the causative interrelationship between autoimmunity and axonal mitochondrial dysfunction in progressive MS (PMS) pathogenesis waits to be provided. METHODS: In the present study, by adopting the NOD mouse model of PMS, we compared the pharmacological effects of the immunosuppressants dexamethasone and fingolimod with those of mTOR inhibitors rapamycin and everolimus that, in addition to immunosuppression, also regulate mitochondrial functioning. Female Non-Obese Diabetic (NOD) mice were immunized with MOG35-55 and treated with drugs to evaluate functional, immune and mitochondrial parameters during disease evolution. RESULTS: We found that dexamethasone and fingolimod did not affect the pattern of progression as well as survival. Conversely, mTOR inhibitors rapamycin and everolimus delayed disease progression and robustly extended survival of immunized mice. The same effects were obtained when treatment was delayed by 30 days after immunization. Remarkably, dexamethasone and fingolimod prompted the same degree of immunosuppression of rapamycin within both spleen and spinal cord of mice. However, only rapamycin prompted mitochondriogenesis by increasing mitochondrial content, and expression of several mitochondrial respiratory complex subunits, thereby preventing mtDNA reduction in the spinal cords of immunized mice. These pharmacodynamic effects were not reproduced in healthy NOD mice, suggesting a disease context-dependent pharmacodynamic effect. DISCUSSION: Data corroborate the key role of mitochondriogenesis to treatment of MS progression, and for the first time disclose the translational potential of mTOR inhibitors in PMS therapy.
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Encefalomielite Autoimune Experimental , Esclerose Múltipla , Feminino , Animais , Camundongos , Esclerose Múltipla/patologia , Inibidores de MTOR , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Neuroproteção , Everolimo/farmacologia , Everolimo/uso terapêutico , Camundongos Endogâmicos NOD , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Dexametasona/farmacologia , Encefalomielite Autoimune Experimental/patologia , Camundongos Endogâmicos C57BLRESUMO
Pancreatic ductal adenocarcinoma (PDAC) has a very poor prognosis. Neoadjuvant chemotherapy is an effective PDAC treatment option, but chemotherapy causes unfavorable side effects. Glucocorticoids (e.g., dexamethasone [DEX]) are administered to reduce side effects of chemotherapy for solid tumors, including pancreatic cancer. Glucocorticoids have both beneficial and detrimental effects, however. We investigated the functional changes and gene-expression profile alterations induced by DEX in PDAC cells. PDAC cells were treated with DEX, and the cell proliferation, migration, invasion, and chemosensitivity to gemcitabine (GEM) were evaluated. The results demonstrated decreased cell proliferative capacity, increased cell migration and invasion, and decreased sensitivity to GEM. A comprehensive genetic analysis revealed marked increases in ECM1 and KRT6A in DEX-treated PDAC cells. We evaluated the effects of ECM1 and KRT6A expression by using PDAC cells transfected with those genes. Neither ECM1 nor KRT6A changed the cells' proliferation, but each enhanced cell migration and invasion. ECM1 decreased sensitivity to GEM. We also assessed the clinicopathological significance of the expressions of ECM1 and KRT6A in 130 cases of PDAC. An immunohistochemical analysis showed that KRT6A expression dominated the poorly differentiated areas. High expressions of these two proteins in PDAC were associated with a poorer prognosis. Our results thus demonstrated that DEX treatment changed PDAC cells' functions, resulting in decreased cell proliferation, increased cell migration and invasion, and decreased sensitivity to GEM. The molecular mechanisms of these changes involve ECM1 and KRT6A, whose expressions are induced by DEX.
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Carcinoma Ductal Pancreático , Dexametasona , Resistencia a Medicamentos Antineoplásicos , Proteínas da Matriz Extracelular , Gencitabina , Queratina-6 , Neoplasias Pancreáticas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Dexametasona/farmacologia , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Gencitabina/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Queratina-6/genética , Queratina-6/metabolismo , Invasividade Neoplásica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Prognóstico , Proteínas da Matriz Extracelular/metabolismoRESUMO
Acute kidney injury (AKI) increases the risk of in-hospital death, adds to expense of care, and risk of early chronic kidney disease. AKI often follows an acute event such that timely treatment could ameliorate AKI and potentially reduce the risk of additional disease. Despite therapeutic success of dexamethasone in animal models, clinical trials have not demonstrated broad success. To improve the safety and efficacy of dexamethasone for AKI, we developed and characterized a novel, kidney-specific nanoparticle enabling specific within-kidney targeting to proximal tubular epithelial cells provided by the megalin ligand cilastatin. Cilastatin and dexamethasone were complexed to H-Dot nanoparticles, which were constructed from generally recognized as safe components. Cilastatin/Dexamethasone/H-Dot nanotherapeutics were found to be stable at plasma pH and demonstrated salutary release kinetics at urine pH. In vivo, they were specifically biodistributed to the kidney and bladder, with 75% recovery in the urine and with reduced systemic toxicity compared to native dexamethasone. Cilastatin complexation conferred proximal tubular epithelial cell specificity within the kidney in vivo and enabled dexamethasone delivery to the proximal tubular epithelial cell nucleus in vitro. The Cilastatin/Dexamethasone/H-Dot nanotherapeutic improved kidney function and reduced kidney cellular injury when administered to male C57BL/6 mice in two translational models of AKI (rhabdomyolysis and bilateral ischemia reperfusion). Thus, our design-based targeting and therapeutic loading of a kidney-specific nanoparticle resulted in preservation of the efficacy of dexamethasone, combined with reduced off-target disposition and toxic effects. Hence, our study illustrates a potential strategy to target AKI and other diseases of the kidney.
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Dexamethasone is frequently prescribed for preterm infants to wean from respiratory support and/or to facilitate extubation. This pre-post intervention prospective study ascertained the impact on clinical (respiratory support) and echocardiographic parameters after dexamethasone therapy in preterm FGR infants compared to AGA infants. Echocardiography was performed within 24 hours before the start and after completion of 10-day therapy. Parameters assessed included those reflecting pulmonary vascular resistance and right ventricular output. Seventeen FGR infants (birth gestation and birthweight 25.2±1.1 weeks and 497±92g) were compared with 22 AGA infants (gestation and birthweight 24.5±0.8 and 663±100g). Baseline respiratory severity score (mean airway pressure x fractional inspired oxygen) was comparable between the groups, (median [interquartile range] FGR: 10 [6, 13] vs AGA: 8±2.8, P=0.08). Pre-dexamethasone parameters of pulmonary vascular resistance (FGR: 0.19±0.03 vs AGA 0.2±0.03, P=0.16) and right ventricular output (FGR: 171±20 vs 174±17 ml/kg/min, P=0.6) were statistically comparable. At post-dexamethasone assessments, the decrease in respiratory severity score was significantly greater in AGA infants, (median [interquartile range] FGR: 10 [6, 13] to 9 [2.6, 13.5], P=0.009 vs AGA: 8±2.8 to 3±1, P<0.0001). Improvement in measures of pulmonary vascular resistance (time to peak velocity/right ventricular ejection time) was greater in AGA infants (FGR: 0.19±0.03 to 0.2±0.03, P=0.13 vs AGA 0.2±0.03 to 0.25±0.03, P<0.0001). The improvement in right ventricular output was significantly greater in AGA infants (171±20 to 190±21, P=0.014 vs 174±17 to 203±22, P<0.0001). This highlights differential cardiorespiratory responsiveness to dexamethasone in extremely preterm FGR infants, which may reflect the in-utero maladaptive state.
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Tissue engineering is a steadily growing field of research due to its wide-ranging applicability in the field of regenerative medicine. Application-dependent mechanical properties of a scaffold material as well as its biocompatibility and tailored functionality represent particular challenges. Here the properties of fibrin-based hydrogels reinforced by functional cytocompatible poly(N-vinylcaprolactam)-based (PVCL) microgels are studied and evaluated. The employment of temperature-responsive microgels decorated by epoxy groups for covalent binding to the fibrin is studied as a function of cross-linking degree within the microgels, microgel concentration, as well as temperature. Rheology reveals a strong correlation between the mechanical properties of the reinforced fibrin-based hydrogels and the microgel rigidity and concentration. The incorporated microgels serve as cross-links, which enable temperature-responsive behavior of the hydrogels, and slow down the hydrogel degradation. Microgels can be additionally used as carriers for active drugs, as demonstrated for dexamethasone. The microgels' temperature-responsiveness allows for triggered release of payload, which is monitored using a bioassay. The cytocompatibility of the microgel-reinforced fibrin-based hydrogels is demonstrated by LIVE/DEAD staining experiments using human mesenchymal stem cells. The microgel-reinforced hydrogels are a promising material for tissue engineering, owing to their superior mechanical performance and stability, possibility of drug release, and retained biocompatibility.
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Pulmonary sarcoidosis is an immune-mediated disorder closely related to Th17/Treg cell imbalance. Dexamethasone has been shown to regulate inflammation and immune responses in sarcoidosis patients. However, the underlying mechanisms of dexamethasone regulating Th17/Treg balance in sarcoidosis remain elusive. Herein, we elucidated the function role of TGF-ß/Smad3 signaling in pulmonary sarcoidosis development and explored the underlying mechanism of dexamethasone in treating pulmonary sarcoidosis. We found that the TGF-ß/Smad3 pathway was inactivated in pulmonary sarcoidosis patients. Propionibacterium acnes (PA) induced mouse model was generated to investigate the function of TGF-ß/Smad3 signaling in vivo. Data indicated that IL17A inhibition with neutralizing antibody and activation of TGF-ß/Smad3 signaling with SRI-011381 alleviated granuloma formation in the sarcoidosis mouse model. Moreover, we revealed that the Th17/Treg cell ratio was increased with PA treatment in mouse bronchoalveolar lavage fluid (BALF) and peripheral blood. The concentration of cytokines produced by Th17 cells (IL-17A, IL-23) was up-regulated in the BALF of PA-treated mice, while those produced by Tregs (IL-10, TGF-ß1) presented significant reduction. The treatment of IL-17A neutralizing antibody or SRI-011381 was demonstrated to rescue the PA-induced changes in the concentration of IL-17A, IL-23, IL-10, and TGF-ß1. Additionally, we demonstrated that dexamethasone treatment activated the TGF-ß/Smad3 signaling in the lung tissues of pulmonary sarcoidosis mice. Dexamethasone was also revealed to promote the rebalancing of the Th17/Treg ratio and attenuated the granuloma formation in pulmonary sarcoidosis. In conclusion, dexamethasone activates the TGF-ß/Smad3 signaling and induces Th17/Treg rebalance, alleviating pulmonary sarcoidosis, which suggests the potential of dexamethasone in treating pulmonary sarcoidosis.
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Dexametasona , Sarcoidose Pulmonar , Animais , Humanos , Camundongos , Anticorpos Neutralizantes/farmacologia , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Granuloma/prevenção & controle , Interleucina-10/metabolismo , Interleucina-17 , Interleucina-23/metabolismo , Sarcoidose Pulmonar/tratamento farmacológico , Linfócitos T Reguladores , Células Th17 , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1RESUMO
BACKGROUND: The 1-mg overnight dexamethasone suppression test is the most frequently used screening test for Cushing's syndrome. It has been proposed that people with obesity may have insufficient plasma dexamethasone levels for the test which may result in false positives. We sought to compare the plasma dexamethasone levels after 1-mg dexamethasone suppression test in healthy obese participants and in optimal-weight participants. METHODS: A total of 30 optimal-weight participants (BMI ≤ 25 kg/m2 ) and 62 obese participants (BMI > 25 kg/m2 ) were enroled in the study. Obese participants were further divided into class 1 (25-29.9 kg/m2 ) and class 2 (>30 kg/m2 ). After a standard overnight 1-mg dexamethasone suppression test, blood samples were obtained for serum cortisol and plasma dexamethasone levels. Plasma dexamethasone levels were quantified using liquid chromatography - mass spectrometry (LC-MS/MS). RESULTS: No significant difference in plasma dexamethasone levels were found between obese and optimal-weight participants (3.31 ± 1.35 vs. 2.82 ± 1.11 nmol/L, mean ± SD; p = .09 respectively). There were also no correlations found between sex, BMI, body surface area and plasma dexamethasone levels. There was also no significant difference in the proportion of participants who achieved a plasma dexamethasone level >3.3 nmol/L in comparison between obesity class 1, obesity class 2, and optimal-weight groups. CONCLUSION: Our results suggest that obesity does not affect plasma dexamethasone levels. However, dexamethasone measurement may still be helpful in patients who are being investigated for Cushing's syndrome and suspected to have a false-positive DST.
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Síndrome de Cushing , Adulto , Humanos , Síndrome de Cushing/diagnóstico , Dexametasona , Hidrocortisona , Cromatografia Líquida , Espectrometria de Massas em Tandem , ObesidadeRESUMO
OBJECTIVE: To investigate the clinical, laboratory findings and signal intensity index (SII) on magnetic resonance imaging (MRI) of patients with bilateral and unilateral macronodular mild autonomous cortisol secretion (MACS). PATIENTS AND MEASUREMENTS: Clinical and laboratory findings of 81 patients with MACS were examined from retrospective records. SII of adenomas and internodular areas were evaluated by MRI. The unilateral group included patients with an adrenal macronodule (≥1 cm) in a single adrenal gland, while the bilateral group included patients with at least one macronodule in both adrenal glands. RESULTS: In total, 46 patients were in the unilateral (57%), while 35 (43%) patients were in the bilateral groups. The dehydroepiandrosterone sulphate (DHEA-S) level was lower in the unilateral than in the bilateral group (p < .001). The presence of type 2 diabetes mellitus (T2DM), glycosylated haemoglobin (HbA1c) and low-density lipoprotein (LDL) concentrations were higher in the bilateral group (p < .05). However, no significant difference was detected in terms of adrenocorticotropic hormone (ACTH) and overnight 1 mg dexamethasone suppression test (DST) between the two groups (p > .05). There was no difference in SII between adenomas within the same patient, as well as between the unilateral and bilateral groups (p > .05). Logistic regression analysis based on the differentiation between unilateral and bilateral macronodular MACS demonstrated that DHEA-S, HbA1c and LDL concentrations were associated factors. CONCLUSION: DHEA-S levels may not be as suppressed in patients with bilateral macronodular MACS as compared to those with unilateral adenoma. T2DM and hypercholesterolaemia have a higher frequency in bilateral patients. However, ACTH, overnight 1 mg DST and SII may not provide additional information for differentiation of bilaterality and unilaterality.
Assuntos
Hidrocortisona , Imageamento por Ressonância Magnética , Humanos , Feminino , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Sulfato de Desidroepiandrosterona/sangue , Hormônio Adrenocorticotrópico/sangue , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/sangue , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/sangueRESUMO
The current study aimed to determine the safety and efficacy of Coag-A through in vivo analysis in CFA induced mice model. Treatment of CFA induced arthritis in mice with Coagulansin-A (10 mg/kg i.p. daily for 28 days), a withanolide obtained from Withania coagulans, as well as standard drug treatment with Dexamethasone (5 mg/kg i.p) was provided. The effect of Coag-A on body weight, relative organ weight, hematology, serum biochemistry, survival rate, oxidative stress markers, and antioxidant enzymes was evaluated. The liver and kidney histopathology were also assessed to ascertain its safety profile. Treatment of arthritic mice with Coag-A considerably improved body weight, relative organ weight of liver, kidney, and spleen, ameliorated hematology and serum biochemistry, and increased survival and antioxidant potential. Coag-A was found to be safer with fewer adverse effects showing hepato-protective, nephroprotective, and anti-inflammatory effect. It also significantly (p < 0.001) improved histopathology of CFA-induced mice when compared with Dexa. In conclusion, compared to dexamethasone, Coag-A has demonstrated a greater therapeutic benefit and fewer side effects in the treatment of arthritis against the CFA-induced model.
Assuntos
Artrite Experimental , Animais , Camundongos , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Artrite Experimental/induzido quimicamente , Masculino , Vitanolídeos/farmacologia , Vitanolídeos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Dexametasona , Estresse Oxidativo/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Rim/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Withania/química , FemininoRESUMO
PURPOSE: Sulfur mustard (SM), a bi-functional alkylating agent, was used during World War I and the Iran-Iraq war. SM toxicity is ten times higher in eyes than in other tissues. Cornea is exceptionally susceptible to SM-injuries due to its anterior positioning and mucous-aqueous interphase. Ocular SM exposure induces blepharitis, photosensitivity, dry eye, epithelial defects, limbal ischemia and stem cell deficiency, and mustard gas keratopathy leading to temporary or permanent vision impairments. We demonstrated that dexamethasone (Dex) is a potent therapeutic intervention against SM-induced corneal injuries; however, its mechanism of action is not well known. Investigations employing proteomic profiling (LC-MS/MS) to understand molecular mechanisms behind SM-induced corneal injury and Dex efficacy were performed in the rabbit cornea exposed to SM and then received Dex treatment. PEAKS studio was used to extract, search, and summarize peptide identity. Ingenuity Pathway Analysis was used for pathway identification. Validation was performed using immunofluorescence. One-Way ANOVA (FDR < 0.05; p < 0.005) and Student's t-test (p < 0.05) were utilized for analyzing proteomics and IF data, respectively. Proteomic analysis revealed that SM-exposure upregulated tissue repair pathways, particularly actin cytoskeleton signaling and inflammation. Prominently dysregulated proteins included lipocalin2, coronin1A, actin-related protein2, actin-related protein2/3 complex subunit2, actin-related protein2/3 complex subunit4, cell division cycle42, ezrin, bradykinin/kininogen1, moesin, and profilin. Upregulated actin cytoskeleton signaling increases F-actin formation, dysregulating cell shape and motility. Dex reversed SM-induced increases in the aforementioned proteins levels to near control expression profiles. Dex aids corneal wound healing and improves corneal integrity via actin cytoskeletal signaling and anti-inflammatory effects following SM-induced injuries.
Assuntos
Substâncias para a Guerra Química , Lesões da Córnea , Gás de Mostarda , Animais , Coelhos , Gás de Mostarda/toxicidade , Substâncias para a Guerra Química/toxicidade , Mediadores da Inflamação/metabolismo , Actinas/metabolismo , Cromatografia Líquida , Proteômica , Espectrometria de Massas em Tandem , Córnea/metabolismo , Lesões da Córnea/induzido quimicamente , Lesões da Córnea/tratamento farmacológico , Citoesqueleto de Actina/metabolismo , Dexametasona/efeitos adversosRESUMO
Efficient tools for controlling molecular functions with exquisite spatiotemporal resolution are much in demand to investigate biological processes in living systems. Here we report an easily synthesized caged dexamethasone for photo-activating cytoplasmic proteins fused to the glucocorticoid receptor. In the dark, it is stable inâ vitro as well as inâ vivo in both zebrafish (Danio rerio) and Xenopus sp, two significant models of vertebrates. In contrast, it liberates dexamethasone upon UV illumination, which has been harnessed to interfere with developmental steps in embryos of these animals. Interestingly, this new system is biologically orthogonal to the one for photo-activating proteins fused to the estrogen ERT receptor, which brings great prospect for activating two distinct proteins down to the single cell level.