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1.
Oxid Med Cell Longev ; 2022: 8235809, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910840

RESUMO

Irisin is a myokine that is secreted from skeletal muscle during exercise and increases lipid metabolism, converting white adipose tissue to brown adipose tissue. Recent studies have shown conflicting results in relation to chronic and acute exercise and irisin. The aim of this study was to evaluate the effects of chronic and acute exercise training on circulating (plasma/serum) irisin level in healthy subjects. We conducted a search of Cochrane Library, PubMed, ISI, Scopus, Embase, and Pedro up to September 2021. A random effects network meta-analysis was performed to calculate the pooled estimate of standardized mean difference (SMD) for acute and chronic exercise effects on irisin level, using Hedge's g statistic. Of the 16 studies included, six were acute exercise studies (175 participants). The aerobic (Hedge's g = 0.23; 95% CI: -0.58, 1.03) and the anaerobic exercises (Hedge's g = 0.12; 95% CI: -0.45, 0.70) were associated with the increased level of irisin, compared to the control. In the ten chronic exercise studies (433 participants), the resistance training was superior to anaerobic and aerobic training (P score = 0.632). However, comparing acute and chronic exercise studies, acute training showed the most excellent potential as the best treatment to improve the irisin level (P score = 0.721). This network meta-analysis showed that acute aerobic exercise has a more effect on irisin levels than acute anaerobic exercise. Also, chronic resistance training has the greatest additive effect on irisin levels compared to chronic aerobic and anaerobic training.


Assuntos
Exercício Físico , Fibronectinas , Terapia por Exercício , Fibronectinas/metabolismo , Voluntários Saudáveis , Humanos , Metanálise em Rede
2.
Oxid Med Cell Longev ; 2022: 9684062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915608

RESUMO

Unbalanced metabolism of an extracellular matrix (ECM) in nucleus pulposus cells (NPCs) is widely acknowledged as the primary cause of intervertebral disc degeneration (IDD). Irisin, a novel myokine, is cleaved from fibronectin type III domain-containing 5 (FNDC5) and has recently been proven to regulate the metabolism of ECM. However, little is known about its potential on NPCs and the development of IDD. Therefore, this study sought to examine the protective effects and molecular mechanism of irisin on IDD in vivo and in vitro. Decreased expression levels of FNDC5 and anabolism markers (COL2A1 and ACAN) but increased levels of catabolism markers (ADAMTS4) were found in degenerative nucleus pulposus (NP) tissues. In a punctured-induced rat IDD model, irisin treatment was found to significantly slow the development of IDD, and in TNF-α-stimulated NPCs, irisin treatment partly reversed the disorder of ECM metabolism. In mechanism, RNA-seq results suggested that irisin treatment affected the Hippo signaling pathway. Further studies revealed that with irisin treatment, the phosphorylation levels of key factors (LATS and YAP) were downregulated, while the expression level of CTGF was upregulated. Moreover, CTGF knockdown partially eliminated the protective effects of irisin on the metabolism of ECM in NPCs, including inhibiting the anabolism and promoting the catabolism. Taken together, this study demonstrated that the expression levels of FNDC5 were decreased in degenerative NP tissues, while irisin treatment promoted the anabolism, inhibited the catabolism of the ECM in NPCs, and delayed the progression of IDD via LATS/YAP/CTGF signaling. These results shed light on the protective actions of irisin on NPCs, leading to the development of a novel therapeutic target for treating IDD.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Animais , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Estimulador Tireóideo de Ação Prolongada/metabolismo , Estimulador Tireóideo de Ação Prolongada/farmacologia , Estimulador Tireóideo de Ação Prolongada/uso terapêutico , Núcleo Pulposo/metabolismo , Ratos , Transdução de Sinais
3.
Cells ; 11(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35805087

RESUMO

Fibronectin is essential for somite formation in the vertebrate embryo. Fibronectin matrix assembly starts as cells emerge from the primitive streak and ingress in the unsegmented presomitic mesoderm (PSM). PSM cells undergo cyclic waves of segmentation clock gene expression, followed by Notch-dependent upregulation of meso1 in the rostral PSM which induces somite cleft formation. However, the relevance of the fibronectin matrix for these molecular processes remains unknown. Here, we assessed the role of the PSM fibronectin matrix in the spatio-temporal regulation of chick embryo somitogenesis by perturbing (1) extracellular fibronectin matrix assembly, (2) integrin-fibronectin binding, (3) Rho-associated protein kinase (ROCK) activity and (4) non-muscle myosin II (NM II) function. We found that integrin-fibronectin engagement and NM II activity are required for cell polarization in the nascent somite. All treatments resulted in defective somitic clefts and significantly perturbed meso1 and segmentation clock gene expression in the PSM. Importantly, inhibition of actomyosin-mediated contractility increased the period of hairy1/hes4 oscillations from 90 to 120 min. Together, our work strongly suggests that the fibronectin-integrin-ROCK-NM II axis regulates segmentation clock dynamics and dictates the spatio-temporal localization of somitic clefts.


Assuntos
Actomiosina , Somitos , Actomiosina/metabolismo , Animais , Relógios Biológicos/fisiologia , Embrião de Galinha , Fibronectinas/metabolismo , Integrinas/metabolismo , Somitos/metabolismo
4.
Cells ; 11(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35805184

RESUMO

Skin is constantly exposed to injuries that are repaired with different outcomes, either regeneration or scarring. Scars result from fibrotic processes modulated by cellular physical forces transmitted by integrins. Fibronectin (FN) is a major component in the provisional matrix assembled to repair skin wounds. FN enables cell adhesion binding of α5ß1/αIIbß3 and αv-class integrins to an RGD-motif. An additional linkage for α5/αIIb is the synergy site located in close proximity to the RGD motif. The mutation to impair the FN synergy region (Fn1syn/syn) demonstrated that its absence permits complete development. However, only with the additional engagement to the FN synergy site do cells efficiently resist physical forces. To test how the synergy site-mediated adhesion affects the course of wound healing fibrosis, we used a mouse model of skin injury and in-vitro migration studies with keratinocytes and fibroblasts on FNsyn. The loss of FN synergy site led to normal re-epithelialization caused by two opposing migratory defects of activated keratinocytes and, in the dermis, induced reduced fibrotic responses, with lower contents of myofibroblasts and FN deposition and diminished TGF-ß1-mediated cell signalling. We demonstrate that weakened α5ß1-mediated traction forces on FNsyn cause reduced TGF-ß1 release from its latent complex.


Assuntos
Fibronectinas , Fator de Crescimento Transformador beta1 , Animais , Fibronectinas/metabolismo , Camundongos , Oligopeptídeos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Pele , Cicatrização
5.
Artigo em Inglês | MEDLINE | ID: mdl-35805580

RESUMO

In this study, the effects of a 12-week exercise program combining aerobic and resistance training on high-fat diet-induced obese Sprague Dawley (SD) rats after the injection of beta-amyloid into the cerebral ventricle were investigated. Changes in physical fitness, cognitive function, blood levels of beta-amyloid and metabolic factors, and protein expressions of neurotrophic factors related to brain function such as BDNF (brain-derived neurotrophic factor) in the quadriceps femoris, hippocampus, and cerebral cortex were analyzed. The subjects were thirty-two 10-week-old SD rats (DBL Co., Ltd., Seoul, Korea). The rats were randomized into four groups: ß-Non-Ex group (n = 8) with induced obesity and ßA25-35 injection into the cerebral ventricle through stereotactic biopsy; ß-Ex group (n = 8) with induced obesity, ßA25-35 injection, and exercise; S-Non-Ex group (n = 8) with an injection of saline in lieu of ßA25-35 as the control; and S-Ex group (n = 8) with saline injection and exercise. The 12-week exercise program combined aerobic training and resistance training. As for protein expressions of the factors related to brain function, the combined exercise program was shown to have a clear effect on activating the following factors: PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha), FNDC5 (fibronectin type III domain-containing protein 5), and BDNF in the quadriceps femoris; TrkB (Tropomyosin receptor kinase B), FNDC5, and BDNF in the hippocampus; PGC-1α, FNDC5, and BDNF in the cerebral cortex. The protein expression of ß-amyloid in the cerebral cortex was significantly lower in the ß-Ex group than in the ß-Non-Ex group (p < 0.05). The 12-week intervention with the combined exercise program of aerobic and resistance training was shown to improve cardiopulmonary function, muscular endurance, and short-term memory. The results demonstrate a set of positive effects of the combined exercise program, which were presumed to have arisen mainly due to its alleviating effect on ß-amyloid plaques, the main cause of reduced brain function, as well as the promotion of protein expressions of PGC-1α, FNDC5, and BDNF in the quadriceps femoris, hippocampus, and cerebral cortex.


Assuntos
Condicionamento Físico Animal , Treinamento de Força , Peptídeos beta-Amiloides , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fibronectinas/metabolismo , Humanos , Obesidade/metabolismo , Obesidade/terapia , Condicionamento Físico Animal/fisiologia , Ratos , Ratos Sprague-Dawley
6.
J Neuroinflammation ; 19(1): 182, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35831910

RESUMO

BACKGROUND: We previously reported higher plasma levels of complement fragments C3a and C5a in neovascular Age-related Macular Degeneration (nAMD) patients with macular fibrosis. This study aimed to understand whether complement activation contributes to the development of macular fibrosis and the underlying mechanisms involved. METHODS: Complement activation was blocked using a C5 neutralizing antibody (BB5.1) in C57BL/6J mice after induction of subretinal fibrosis using the two-stage laser protocol. Fibrotic lesions were examined 10 days after the 2nd laser through fundus examination and immunohistochemistry. The expression of C5aR in fibrotic lesions and retinal pigment epithelial (RPE) cultures were examined by confocal microscopy. Primary murine RPE cells were treated with C3a or C5a (10-100 ng/mL) or TGF-ß2 (10 ng/mL). Epithelial-to-mesenchymal transition (EMT) was assessed through various readouts. The expression of E-cadherin, vimentin, fibronectin, α-SMA, Slug, ERK/AKT and pSMAD2/3 were determined by Western blot and immunocytochemistry. Collagen contraction and wound-healing assays were used as functional readouts of EMT. The production of IL-6, TGF-ß1, TGF-ß2 and VEGF by RPE cells were determined by ELISA. PMX53 was used to block C5aR in RPE cultures and in vivo in mice with subretinal fibrosis. RESULTS: Extensive C5b-9 deposition was detected at the site of subretinal fibrosis. BB5.1 treatment completely abrogated complement activation and significantly reduced subretinal fibrosis. C5aR was detected in RPE and infiltrating MHC-II+ cells in subretinal fibrosis. In vitro, RPE cells constitutively express C5/C5a and C5aR, and their expression was increased by TGF-ß2 treatment. C5a but not C3a increased fibronectin, α-SMA, vimentin and Slug expression, and decreased E-cadherin expression in RPE cells. C5a treatment also increased the contractility and migration of RPE cells and enhanced the production of VEGF and TGF-ß1/2. C5a treatment induced pSmad2/3 and pERK1/2 expression in RPE cells and this was blocked by PMX53. PMX53 treatment significantly reduced sodium fluorescein leakage in the subretinal fibrosis model, while collagen-I+ lesions only mildly reduced. CONCLUSIONS: Complement activation is critically involved in the development of subretinal fibrosis, partially through C5a-C5aR-mediated EMT in RPE cells. Targeting complement activation rather than C5a may be a novel approach for the management of macular fibrosis.


Assuntos
Transição Epitelial-Mesenquimal , Fator de Crescimento Transformador beta1 , Fator de Crescimento Transformador beta2 , Animais , Caderinas , Colágeno , Ativação do Complemento , Células Epiteliais/patologia , Fibronectinas/metabolismo , Fibrose , Camundongos , Camundongos Endogâmicos C57BL , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vimentina/metabolismo
7.
FASEB J ; 36(8): e22477, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35881071

RESUMO

Diabetes may prevent kidney repair and sensitize the kidney to fibrosis or scar formation. To test this possibility, we examined renal fibrosis induced by unilateral ureteral obstruction (UUO) in diabetic mouse models. Indeed, UUO induced significantly more renal fibrosis in both Akita and STZ-induced diabetic mice than in nondiabetic mice. The diabetic mice also had more apoptosis and interstitial macrophage infiltration during UUO. In vitro, hypoxia induced higher expression of the fibrosis marker protein fibronectin in high glucose-conditioned renal tubular cells than in normal glucose cells. Mechanistically, hypoxia induced significantly more hypoxia-inducible factor-1 α (HIF-1 α) in high glucose cells than in normal glucose cells. Inhibition of HIF-1 attenuated the expression of fibronectin induced by hypoxia in high-glucose cells. Consistently, UUO induced significantly higher HIF-1α expression along with fibrosis in diabetic mice kidneys than in nondiabetic kidneys. The increased expression of fibrosis induced by UUO in diabetic mice was diminished in proximal tubule-HIF-1α-knockout mice. Together, these results indicate that diabetes sensitizes kidney tissues and cells to fibrogenesis probably by enhancing HIF-1 activation.


Assuntos
Diabetes Mellitus Experimental , Nefropatias , Obstrução Ureteral , Animais , Diabetes Mellitus Experimental/metabolismo , Fibronectinas/metabolismo , Fibrose , Glucose/metabolismo , Hipóxia/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Rim/metabolismo , Nefropatias/patologia , Camundongos , Obstrução Ureteral/metabolismo
8.
Cells ; 11(13)2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35805206

RESUMO

Cells actively sense differences in topology, matrix elasticity and protein composition of the extracellular microenvironment and adapt their function and morphology. In this study, we focus on the cross-talk between matrix stiffness and protein coating density that regulates morphology and proliferation dynamics of single myocytes. For this, C2C12 myocytes were monitored on L-DOPA functionalized hydrogels of 22 different elasticity and fibronectin density compositions. Static images were recorded and statistically analyzed to determine morphological differences and to identify the optimized extracellular matrix (ECM). Using that information, selected ECMs were used to study the dynamics before and after cell proliferation by statistical comparison of distinct cell states. We observed a fibronectin-density-independent increase of the projected cell area until 12 kPa. Additionally, changes in fibronectin density led to an area that was optimum at about 2.6 µg/cm2, which was confirmed by independent F-actin analysis, revealing a maximum actin-filament-to-cell-area ratio of 7.5%. Proliferation evaluation showed an opposite correlation between cell spreading duration and speed to matrix elasticity and protein density, which did not affect cell-cycle duration. In summary, we identified an optimized ECM composition and found that independent matrix properties regulate distinct cell characteristics.


Assuntos
Matriz Extracelular , Fibronectinas , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Hidrogéis , Células Musculares/metabolismo
9.
Cells ; 11(14)2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35883601

RESUMO

Delivering and retaining cells in areas of interest is an ongoing challenge in tissue engineering. Here we introduce a novel approach to fabricate osteoblast-loaded titanium suitable for cell delivery for bone integration, regeneration, and engineering. We hypothesized that titanium age influences the efficiency of protein adsorption and cell loading onto titanium surfaces. Fresh (newly machined) and 1-month-old (aged) commercial grade 4 titanium disks were prepared. Fresh titanium surfaces were hydrophilic, whereas aged surfaces were hydrophobic. Twice the amount of type 1 collagen and fibronectin adsorbed to fresh titanium surfaces than aged titanium surfaces after a short incubation period of three hours, and 2.5-times more fibronectin than collagen adsorbed regardless of titanium age. Rat bone marrow-derived osteoblasts were incubated on protein-adsorbed titanium surfaces for three hours, and osteoblast loading was most efficient on fresh titanium adsorbed with fibronectin. The number of osteoblasts loaded using this synergy between fresh titanium and fibronectin was nine times greater than that on aged titanium with no protein adsorption. The loaded cells were confirmed to be firmly attached and functional. The number of loaded cells was strongly correlated with the amount of protein adsorbed regardless of the protein type, with fibronectin simply more efficiently adsorbed on titanium surfaces than collagen. The role of surface hydrophilicity of fresh titanium surfaces in increasing protein adsorption or cell loading was unclear. The hydrophilicity of protein-adsorbed titanium increased with the amount of protein but was not the primary determinant of cell loading. In conclusion, the osteoblast loading efficiency was dependent on the age of the titanium and the amount of protein adsorption. In addition, the efficiency of protein adsorption was specific to the protein, with fibronectin being much more efficient than collagen. This is a novel strategy to effectively deliver osteoblasts ex vivo and in vivo using titanium as a vehicle.


Assuntos
Fibronectinas , Titânio , Animais , Adesão Celular/fisiologia , Fibronectinas/metabolismo , Osteoblastos/metabolismo , Ratos , Propriedades de Superfície , Titânio/química
10.
Front Endocrinol (Lausanne) ; 13: 918467, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774143

RESUMO

Irisin is a myokine involved in the browning of white adipose tissue and regulation of energy expenditure, glucose homeostasis and insulin sensitivity. Debated evidence exists on the metabolic role played by irisin in children with overweight or obesity, while few information exist in children with Prader Willi Syndrome (PWS), a condition genetically prone to obesity. Here we assessed serum irisin in relation to the metabolic profile and body composition in children and adolescents with and without PWS. In 25 PWS subjects [age 6.6-17.8y; body mass index standard deviation score (BMI SDS) 2.5 ± 0.3] and 25 age, and BMI-matched controls (age 6.8-18.0y; BMI SDS, 2.8 ± 0.1) we assessed irisin levels and metabolic profile inclusive of oral glucose tolerance test (OGTT), and body composition by dual-energy X-ray absorptiometry (DXA). In PWS, we recorded lower levels of fat-free mass (FFM) (p <0.05), fasting (p<0.0001) and 2h post-OGTT insulin (p<0.05) and lower insulin resistance as expressed by homeostatic model of insulin resistance (HOMA-IR) (p<0.0001). Irisin levels were significantly lower in PWS group than in controls with common obesity (p<0.05). In univariate correlation analysis, positive associations linked irisin to insulin OGTT0 (p<0.05), insulin OGTT120 (p<0.005), HOMA-IR (p<0.05) and fasting C-peptide (p<0.05). In stepwise multivariable regression analysis, irisin levels were independently predicted by insulin OGTT120. These results suggest a link between irisin levels and insulin sensitivity in two divergent models of obesity.


Assuntos
Fibronectinas , Glucose , Obesidade , Síndrome de Prader-Willi , Adolescente , Glicemia/metabolismo , Criança , Fibronectinas/sangue , Fibronectinas/metabolismo , Glucose/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Obesidade/sangue , Síndrome de Prader-Willi/sangue , Síndrome de Prader-Willi/metabolismo
11.
Elife ; 112022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35796649

RESUMO

Staphylococcus epidermidis causes some of the most hard-to-treat clinical infections by forming biofilms: Multicellular communities of bacteria encased in a protective matrix, supporting immune evasion and tolerance against antibiotics. Biofilms occur most commonly on medical implants, and a key event in implant colonization is the robust adherence to the surface, facilitated by interactions between bacterial surface proteins and host matrix components. S. epidermidis is equipped with a giant adhesive protein, extracellular matrix-binding protein (Embp), which facilitates bacterial interactions with surface-deposited, but not soluble fibronectin. The structural basis behind this selective binding process has remained obscure. Using a suite of single-cell and single-molecule analysis techniques, we show that S. epidermidis is capable of such distinction because Embp binds specifically to fibrillated fibronectin on surfaces, while ignoring globular fibronectin in solution. S. epidermidis adherence is critically dependent on multivalent interactions involving 50 fibronectin-binding repeats of Embp. This unusual, Velcro-like interaction proved critical for colonization of surfaces under high flow, making this newly identified attachment mechanism particularly relevant for colonization of intravascular devices, such as prosthetic heart valves or vascular grafts. Other biofilm-forming pathogens, such as Staphylococcus aureus, express homologs of Embp and likely deploy the same mechanism for surface colonization. Our results may open for a novel direction in efforts to combat devastating, biofilm-associated infections, as the development of implant materials that steer the conformation of adsorbed proteins is a much more manageable task than avoiding protein adsorption altogether.


A usually harmless bacterium called Staphylococcus epidermidis lives on human skin. Sometimes it makes its way into the bloodstream through a cut or surgical procedure, but it rarely causes blood infections. It can, however, cause severe infections when it attaches to the surface of a medical implant like a pacemaker or an artificial replacement joint. It does this by forming a colony of bacteria on the implant's surface called a biofilm, which protects the bacteria from destruction by the immune system or antibiotics. Understanding how Staphylococcus epidermidis implant infections start is critical to preventing them. This information may help scientists develop infection-resistant implants or new treatments for implant infections. Scientists suspect that Staphylococcus epidermidis attaches to implants by binding to a human protein called fibronectin, which coats medical implants in the human body. Another protein on the surface of the bacteria, called Embp, facilitates the connection. But why the bacteria attach to fibronectin on implants, and not fibronectin molecules in the bloodstream, is unclear. Now, Khan, Aslan et al. show that Embp forms a Velcro-like bond with fibronectin on the surface of implants. In the experiments, Khan and Aslan et al. used powerful microscopes to create 3-dimensional images of the interactions between Embp and fibronectin. The experiments showed that Embp's attachment site is hidden on the globe-shaped form of fibronectin circulating in the blood. But when fibronectin covers an implant surface, it forms a fibrous network, and Embp can attach to it with up to 50 Velcro-like individual connections. These many weak connections form a strong bond that withstands the force of blood pumping past. The experiments show that the fibrous coating of fibronectin on implants makes them a hotspot for Staphylococcus epidermidis infections. Finding ways to block Embp from attaching to fibronectin on implants, or altering the form fibronectin takes on implants, may help prevent these infections. Many bacteria that form biofilms have an Embp-like protein. As a result, these discoveries may also help scientists develop prevention or treatment strategies for other bacterial biofilm infections.


Assuntos
Proteínas de Transporte , Infecções Estafilocócicas , Proteínas de Bactérias/metabolismo , Biofilmes , Proteínas de Transporte/metabolismo , Fibronectinas/metabolismo , Humanos , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis
12.
ACS Chem Neurosci ; 13(12): 1782-1789, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35652596

RESUMO

A high-fat, high-fructose diet (HFFD) impairs cognitive functions and increases susceptibility to neurodegenerative disorders. Irisin and heat shock protein 70 (HSP70) are well known for their role in neuroprotection. The possible neuroprotective effects of fenofibrate on HFFD-induced cognitive dysfunction and the involvement of irisin and HSP70 in these effects were investigated in this study. Rats were divided into normal control, HFFD, dimethylsulfoxide+HFFD, and fenofibrate+HFFD groups. At the end of the experiment, fenofibrate treatment restored hippocampus histological characteristics to almost normal and improved HFFD-induced cognitive deficit. It reduced body weight gain and had hypolipidemic effects by significantly lowering total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels while increasing high-density lipoprotein cholesterol levels. It has antioxidant and anti-inflammatory effects as it significantly reduced the hippocampal malondialdehyde, interleukin-6, and tumor necrosis factor-alpha levels, while significantly increasing the reduced glutathione level. It prevented HFFD-induced hypoxia by significantly lowering hippocampal vascular endothelial growth factor and hypoxia-inducible factor-1 alpha levels. It significantly activated the hippocampal peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α)/irisin/brain-derived neurotrophic factor pathway. It significantly increased hippocampal HSP70 while decreasing the HSP90 levels. It enhanced synaptic plasticity by significantly upregulating the hippocampal relative GluR1 gene expression. Furthermore, hippocampal irisin levels in the HFFD group were found to be positively correlated with cognitive function, hippocampal HSP70, and relative GluR1 gene expression levels, while negatively correlated with hippocampal HSP90 and HIF1α levels. Therefore, fenofibrate may be used as a potential medication to treat HFFD-induced neurodegenerative disorders.


Assuntos
Disfunção Cognitiva , Dieta Hiperlipídica , Fenofibrato , Fibronectinas , Frutose , Proteínas de Choque Térmico , Animais , Colesterol/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Dieta Hiperlipídica/efeitos adversos , Fenofibrato/farmacologia , Fibronectinas/metabolismo , Frutose/administração & dosagem , Frutose/efeitos adversos , Proteínas de Choque Térmico/metabolismo , Hipóxia/tratamento farmacológico , Hipóxia/metabolismo , Ratos , Fator A de Crescimento do Endotélio Vascular
13.
Theranostics ; 12(9): 4399-4414, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35673579

RESUMO

Rationale: Dysadherin is a tumor-associated, membrane-embedded antigen found in multiple types of cancer cells, and associated with malignant behavior of cancer cells; however, the fundamental molecular mechanism by which dysadherin drives aggressive phenotypes of cancer is not yet fully determined. Methods: To get a mechanistic insight, we explored the physiological relevance of dysadherin on intestinal tumorigenesis using dysadherin knockout mice and investigated its impact on clinicopathological features in patients with advanced colorectal cancer (CRC). Next, to discover the downstream signaling pathways of dysadherin, we applied bioinformatic analysis using gene expression data of CRC patient tumors and dysadherin knockout cancer cells. Additionally, comprehensive proteomic and molecular analyses were performed to identify dysadherin-interacting proteins and their functions. Results: Dysadherin deficiency suppressed intestinal tumorigenesis in both genetic and chemical mouse models. Moreover, increased dysadherin expression in cancer cells accounted for shorter survival in CRC patients. Comprehensive bioinformatics analyses suggested that the effect of dysadherin deletion is linked to a reduction in the extracellular matrix receptor signaling pathway. Mechanistically, the extracellular domain of dysadherin bound fibronectin and enhanced cancer cell adhesion to fibronectin, facilitating the activation of integrin-mediated mechanotransduction and leading to yes-associated protein 1 activation. Dysadherin-fibronectin interaction promoted cancer cell growth, survival, migration, and invasion, effects collectively mediated the protumor activity of dysadherin. Conclusion: Our results highlight a novel function of dysadherin as a driver of mechanotransduction that stimulates CRC progression, providing a potential therapy strategy for CRC.


Assuntos
Neoplasias Colorretais , Canais Iônicos/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas de Neoplasias , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/patologia , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Mecanotransdução Celular , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas de Neoplasias/genética , Proteômica
14.
Stem Cell Res Ther ; 13(1): 250, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690799

RESUMO

BACKGROUND: Adipose-derived stromal cells (ASCs) possess a multitude of regenerative capabilities, which include immunomodulation, angiogenesis, and stimulation of extracellular matrix (ECM) remodeling. However, the underlying mechanisms leading to ECM remodeling remain largely elusive and highlight the need for functional in vitro models for mode of action studies. Therefore, the purpose of this study was to develop an in vitro co-culture model to investigate the capabilities of ASCs to modulate fibroblasts and ECM. METHODS: An ECM in vitro model with ASCs and normal human dermal fibroblasts (NHDFs) was established utilizing macromolecular crowding, ascorbic acid, and TGF-ß stimulation. Paracrine and juxtacrine co-cultures were created using transwell inserts and cell cultures with direct cell-cell contacts. The cultures were screened using RT2 PCR Profiler Arrays; the protein levels of myofibroblast differentiation marker alpha smooth muscle actin (αSMA) and ECM remodeling enzymes were analyzed using western blot on cell lysates; the formation of collagen type I, III, VI, and fibronectin was investigated using ELISA on culture supernatants; and the deposition of collagens was analyzed using immunocytochemistry. RESULTS: TGF-ß stimulation of NHDF monocultures increased the expression of 18 transcripts relevant for ECM formation and remodeling, the protein levels of αSMA and matrix metalloproteinase-2 (MMP-2), the formation of collagen type I, III, VI, and fibronectin, and the deposition of collagen type I and VI and decreased the protein levels of MMP-14. Inclusion of ASCs in the ECM co-culture model increased the formation of collagen type I and III through paracrine mechanisms and the formation of collagen type VI through juxtacrine mechanisms. CONCLUSIONS: The co-culture model provides effective stimulation of NHDF monocultures by TGF-ß for enhanced formation and deposition of ECM. In the model, ASCs induce changes in ECM by increasing formation of collagen type I, III and VI. The obtained results could guide further investigations of ASCs' capabilities and underlying mechanisms related to ECM formation and remodeling.


Assuntos
Fibronectinas , Metaloproteinase 2 da Matriz , Células Cultivadas , Técnicas de Cocultura , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos , Fibronectinas/metabolismo , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Células Estromais/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
Am J Physiol Cell Physiol ; 323(1): C226-C235, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704698

RESUMO

Neogenin, a transmembrane receptor, was recently found in kidney cells and immune cells. However, the function of neogenin signaling in kidney is not clear. Mesangial cells (MCs) are a major source of extracellular matrix (ECM) proteins in glomerulus. In many kidney diseases, MCs are impaired and manifest myofibroblast phenotype. Overproduction of ECM by the injured MCs promotes renal injury and accelerates the progression of kidney diseases. The present study aimed to determine if neogenin receptor was expressed in MCs and if the receptor signaling regulated ECM protein production by MCs. We showed that neogenin was expressed in the glomerular MCs. Deletion of neogenin using CRISPR/Cas9 lentivirus system significantly reduced the abundance of fibronectin, an ECM protein. Netrin-1, a ligand for neogenin, also significantly decreased fibronectin production by MCs and decreased neogenin protein expression in MCs. Furthermore, treatment of human MCs with high glucose (HG, 25 mM) significantly increased the protein abundance of neogenin as early as 8 h. Consistently, neogenin expression in glomerulus significantly increased in the eNOS-/-db/db diabetic mice starting as early as the age of 8 wk and this increase sustained at least to the age of 24 wk. We further found that the HG-induced increase in neogenin abundance was blunted by antioxidant PEG-catalase and N-acetyl cysteine. Taken together, our results suggest a new mechanism of regulation of fibronectin production by MCs. This previously unrecognized neogenin-fibronectin pathway may contribute to glomerular injury responses during the course of diabetic nephropathy.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Proteínas de Membrana , Animais , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Glucose/metabolismo , Proteínas de Membrana/genética , Células Mesangiais/metabolismo , Camundongos , Fatores de Transcrição/metabolismo
16.
Biochem Biophys Res Commun ; 618: 100-106, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-35716593

RESUMO

Regeneration of periodontal hard tissues damaged by Porphyromonas gingivalis (P. gingivalis) is essential for tooth stability and dental health. Irisin, a myokine secreted by skeletal muscle, is involved in different biological processes, such as myogenesis, adipogenesis, neurogenesis and osteogenesis. However, whether irisin regulates the osteogenic/cementogenic differentiation of human periodontal ligament cell (hPDLCs), especially under P. gingivalis-triggered inflammation, remains unknown. In this study, we verified the suppression role of P. gingivalis in the osteogenic/cementogenic differentiation of hPDLCs. Also, compared with the control cells, hPDLCs with irisin stimulation showed higher expression of osteogenic-/cementogenic-related markers, ALP activity and mineralization ability, as measured by RT-qPCR, western blotting, ALP staining and Alizarin red staining, respectively. Moreover, the osteogenic/cementogenic differentiation-facilitating role of irisin was also demonstrated under P. gingivalis-elicited inflammation, which implied a rescue function of irisin in P. gingivalis-suppressed hPDLC differentiation. Finally, the underlying mechanism involved in the process was explored. We observed that the p38 signaling pathway was activated during irisin-accelerated hPDLC differentiation. Furthermore, hPDLC differentiation was weakened after the p38 inhibitor was applied. In summary, we found that irisin can facilitate the osteogenic/cementogenic differentiation of hPDLCs partially through the p38 signaling pathway, which may provide evidence for the regeneration of P. gingivalis-destroyed periodontal hard tissues.


Assuntos
Fibronectinas , Sistema de Sinalização das MAP Quinases , Osteogênese , Ligamento Periodontal , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Fibronectinas/metabolismo , Humanos , Inflamação/metabolismo , Osteogênese/fisiologia , Ligamento Periodontal/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Int Immunol ; 34(8): 435-444, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35689642

RESUMO

LILRB4 (B4, also known as ILT3/CD85k) is an immune checkpoint of myeloid lineage cells, albeit its mode of function remains obscure. Our recent identification of a common ligand for both human B4 and its murine ortholog gp49B as the fibronectin (FN) N-terminal 30 kDa domain poses the question of how B4/gp49B regulate cellular activity upon recognition of FN in the plasma and/or the extracellular matrix. Since FN in the extracellular matrix is tethered by FN-binding integrins, we hypothesized that B4/gp49B would tether FN in cooperation with integrins on the cell surface, thus they should be in close vicinity to integrins spatially. This scenario suggests a mode of function of B4/gp49B by which the FN-induced signal is regulated. The FN pull-down complex was found to contain gp49B and integrin ß 1 in bone marrow-derived macrophages. The confocal fluorescent signals of the three molecules on the intrinsically FN-tethering macrophages were correlated to each other. When FN-poor macrophages adhered to culture plates, the gp49-integrin ß 1 signal correlation increased at the focal adhesion, supporting the notion that gp49B and integrin ß 1 become spatially closer to each other there. Adherence of RAW264.7 and THP-1 cells to immobilized FN induced phosphorylation of spleen tyrosine kinase, whose level was augmented under B4/gp49B deficiency. Thus, we concluded that B4/gp49B can co-tether FN in cooperation with integrin in the cis configuration on the same cell, forming a B4/gp49B-FN-integrin triplet as a regulatory unit of a focal adhesion-dependent pro-inflammatory signal in macrophages.


Assuntos
Fibronectinas , Integrinas , Animais , Adesão Celular , Fibronectinas/química , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Humanos , Integrinas/metabolismo , Macrófagos/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Fosforilação , Receptores Imunológicos/metabolismo
18.
Mol Biol Cell ; 33(9): ar78, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704469

RESUMO

Cellular differentiation is characterized by changes in cell morphology that are largely determined by actin dynamics. We previously showed that depolymerization of the actin cytoskeleton triggers the differentiation of preadipocytes into mature adipocytes as a result of inhibition of the transcriptional coactivator activity of megakaryoblastic leukemia 1 (MKL1). The extracellular matrix (ECM) influences cell morphology via interaction with integrins, and reorganization of the ECM is associated with cell differentiation. Here we show that interaction between actin dynamics and ECM rearrangement plays a key role in adipocyte differentiation. We found that depolymerization of the actin cytoskeleton precedes disruption and degradation of fibrillar fibronectin (FN) structures at the cell surface after the induction of adipogenesis in cultured preadipocytes. A FN matrix suppressed both reorganization of the actin cytoskeleton into the pattern characteristic of adipocytes and terminal adipocyte differentiation, and these inhibitory effects were overcome by knockdown of integrin α5 (ITGα5). Peroxisome proliferator-activated receptor γ was required for down-regulation of FN during adipocyte differentiation, and MKL1 was necessary for the expression of ITGα5. Our findings suggest that cell-autonomous down-regulation of FN-ITGα5 interaction contributes to reorganization of the actin cytoskeleton and completion of adipocyte differentiation.


Assuntos
Adipogenia , Fibronectinas , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Diferenciação Celular , Fibronectinas/metabolismo , Integrina alfa5/metabolismo
19.
Sci Rep ; 12(1): 9285, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35662268

RESUMO

This research is to investigate the expression of the TGF-ß1/Smads/α-SMA pathway and its effect on bladder histology and function in children with neurogenic bladder (NB). The bladder specimens from 10 children with NB and 8 children with vesicoureteral junction obstruction were collected into the NB and control groups. The expression of TGF-ß1, Smad2, Smad3, Smad4, Smad6, α-SMA, fibronectin, collagen I and collagen III in bladder tissues was detected. In addition, the histological characteristics of the bladder were evaluated. A preoperative urodynamic study was performed on all children with NB. We analysed the correlations among the expression of the marker protein a-SMA in myofibroblasts, effector cells of the pathway, and bladder function parameters. Compared with those in the control group, the expression of TGF-ß1, Smad2, Smad3, Smad4, α-SMA, fibronectin, collagen I and collagen III was significantly increased in the NB group, while the expression of Smad6 was decreased (p < 0.01). HE and Masson staining in the NB group showed increased collagen levels and hypertrophy of smooth muscle cells. Children with NB had a low bladder volume ratio (BVR), low compliance (△C) and high maximum bladder pressure, low maximum flow rate, large postvoid residual volume, low bladder contraction index and low bladder voiding efficiency. The expression of α-SMA was negatively correlated with the BVR (r = - 0.7066, P = 0.0223) and △C (r = - 0.6516, P = 0.0412). We conclude that the TGF-ß1/Smads/α-SMA pathway is activated in the bladder tissue of children with NB and may be involved in the processes causing histological and functional changes.


Assuntos
Fator de Crescimento Transformador beta1 , Bexiga Urinaria Neurogênica , Actinas/metabolismo , Criança , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Fibronectinas/metabolismo , Humanos , Transdução de Sinais , Proteínas Smad/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
20.
Pak J Pharm Sci ; 35(2): 539-546, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35642410

RESUMO

Dexamethasone is a glucocorticoid that is used for the treatment of interstitial pneumonia and pulmonary fibrosis as it possesses anti-inflammatory and anti-fibrosis properties. In the current study, A549 cells were exposed to paraquat, dexamethasone, or both of them, to investigate the potential effect of dexamethasone against paraquat-triggered poisoning in A549 cells. The inflammatory response was evaluated by measuring tumor necrosis factor-α, interleukin-1ß, and interleukin-6 while the degree of fibrosis was assessed by detecting collagen I and fibronectin using enzyme-linked immunosorbent assay. Western blotting was used to assess the protein expression of apoptotic proteins as well as transforming growth factor-ß1, Smad 3 and phospho-Smad 3. DNA ladder assay was performed to estimate DNA damage in different groups of the alveolar epithelial cells. Dexamethasone protected against paraquat-induced inflammatory response as shown by the significantly reduced levels of the pro-inflammatory cytokines and it also alleviated paraquat-provoked fibrosis as it substantially diminished collagen I and fibronectin levels. Moreover, dexamethasone remarkably decreased the relative expression levels of transforming growth factor-ß1 and phospho-Smad3 that were upregulated upon PQ treatment. Dexamethasone also protected against paraquat-induced genotoxicity and apoptosis. In conclusion, dexamethasone may protect against paraquat-induced inflammation, fibrosis, genotoxicity, and apoptosis via modulating TGF-ß1/Smad 3 signaling pathway.


Assuntos
Dexametasona , Fibrose Pulmonar , Proteína Smad3 , Fator de Crescimento Transformador beta1 , Células A549 , Apoptose , Colágeno/metabolismo , Dexametasona/farmacologia , Fibronectinas/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Paraquat/toxicidade , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/prevenção & controle , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
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