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1.
PLoS One ; 15(10): e0234372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091058

RESUMO

There arose one of the most important ecological transitions in Earth's history approximately 750 million years ago during the middle Neoproterozoic Era (1000 to 541 million years ago, Ma). Biomarker evidence suggests that around this time there was a rapid shift from a predominantly bacterial-dominated world to more complex ecosystems governed by eukaryotic primary productivity. The resulting 'Rise of the algae' led to dramatically altered food webs that were much more efficient in terms of nutrient and energy transfer. Yet, what triggered this ecological shift? In this study we examined the theory that it was the alleviation of phosphorus (P) deficiency that gave eukaryotic alga the prime opportunity to flourish. We performed laboratory experiments on the cyanobacterium Synechocystis salina and the eukaryotic algae Tetraselmis suecica and examined their ability to compete for phosphorus. Both these organisms co-occur in modern European coastal waters and are not known to have any allelopathic capabilities. The strains were cultured in mono and mixed cultures in chemostats across a range of dissolved inorganic phosphorus (DIP) concentrations to reflect modern and ancient oceanic conditions of 2 µM P and 0.2 µM P, respectively. Our results show that the cyanobacteria outcompete the algae at the low input (0.2 µM P) treatment, yet the eukaryotic algae were not completely excluded and remained a constant background component in the mixed-culture experiments. Also, despite their relatively large cell size, the algae T. suecica had a high affinity for DIP. With DIP input concentrations resembling modern-day levels (2 µM), the eukaryotic algae could effectively compete against the cyanobacteria in terms of total biomass production. These results suggest that the availability of phosphorus could have influenced the global expansion of eukaryotic algae. However, P limitation does not seem to explain the complete absence of eukaryotic algae in the biomarker record before ca. 750 Ma.


Assuntos
Clorófitas/crescimento & desenvolvimento , Fósforo/metabolismo , Synechocystis/crescimento & desenvolvimento , Algoritmos , Fosfatase Alcalina/metabolismo , Técnicas de Cultura Celular por Lotes , Biomassa , Clorofila A/metabolismo , Clorófitas/metabolismo , Meios de Cultura/química , Synechocystis/metabolismo
2.
Small ; 16(38): e2003010, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32815251

RESUMO

Currently, mesenchymal stem cells (MSCs)-based therapies for bone regeneration and treatments have gained significant attention in clinical research. Though many chemical and physical cues which influence the osteogenic differentiation of MSCs have been explored, scaffolds combining the benefits of Zn2+ ions and unique nanostructures may become an ideal interface to enhance osteogenic and anti-infective capabilities simultaneously. In this work, motivated by the enormous advantages of Zn-based metal-organic framework-derived nanocarbons, C-ZnO nanocarbons-modified fibrous scaffolds for stem cell-based osteogenic differentiation are constructed. The modified scaffolds show enhanced expression of alkaline phosphatase, bone sialoprotein, vinculin, and a larger cell spreading area. Meanwhile, the caging of ZnO nanoparticles can allow the slow release of Zn2+ ions, which not only activate various signaling pathways to guide osteogenic differentiation but also prevent the potential bacterial infection of implantable scaffolds. Overall, this study may provide new insight for designing stem cell-based nanostructured fibrous scaffolds with simultaneously enhanced osteogenic and anti-infective capabilities.


Assuntos
Carbono/química , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Osteogênese/fisiologia , Tecidos Suporte/química , Óxido de Zinco/química , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura , Transdução de Sinais , Engenharia Tecidual , Vinculina/metabolismo
3.
Life Sci ; 258: 118195, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781073

RESUMO

AIMS: The estrogen-ERα axis participates in osteoblast maturation. This study was designed to further evaluated the roles of the estrogen-ERα axis in bone healing and the possible mechanisms. MAIN METHODS: Female ICR mice were created a metaphyseal bone defect in the left femurs and administered with methylpiperidinopyrazole (MPP), an inhibitor of ERα. Bone healing was evaluated using micro-computed tomography. Colocalization of ERα with alkaline phosphatase (ALP) and ERα translocation to mitochondria were determined. Levels of ERα, ERß, PECAM-1, VEGF, and ß-actin were immunodetected. Expression of chromosomal Runx2, ALP, and osteocalcin mRNAs and mitochondrial cytochrome c oxidase (COX) I and COXII mRNAs were quantified. Angiogenesis was measured with immunohistochemistry. KEY FINDINGS: Following surgery, the bone mass was time-dependently augmented in the bone-defect area. Simultaneously, levels of ERα were specifically upregulated and positively correlated with bone healing. Administration of MPP to mice consistently decreased levels of ERα and bone healing. As to the mechanisms, osteogenesis was enhanced in bone healing, but MPP attenuated osteoblast maturation. In parallel, expressions of osteogenesis-related ALP, Runx2, and osteocalcin mRNAs were induced in the injured zone. Treatment with MPP led to significant inhibition of the alp, runx2, and osteocalcin gene expressions. Remarkably, administration of MPP lessened translocation of ERα to mitochondria and expressions of mitochondrial energy production-related coxI and coxII genes. Furthermore, exposure to MPP decreased levels of PECAM-1 and VEGF in the bone-defect area. SIGNIFICANCE: The present study showed the contributions of the estrogen-ERα axis to bone healing through stimulation of energy production, osteoblast maturation, and angiogenesis.


Assuntos
Regeneração Óssea , Diferenciação Celular , Metabolismo Energético , Receptor alfa de Estrogênio/metabolismo , Neovascularização Fisiológica , Osteoblastos/citologia , Transdução de Sinais , Fosfatase Alcalina/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Calo Ósseo/efeitos dos fármacos , Calo Ósseo/patologia , Diferenciação Celular/efeitos dos fármacos , Cromossomos de Mamíferos/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Regulação para Cima/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
4.
PLoS One ; 15(8): e0237479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790806

RESUMO

OBJECTIVE: As native cartilage consists of different phenotypical zones, this study aims to fabricate different types of neocartilage constructs from collagen hydrogels and human mesenchymal stromal cells (MSCs) genetically modified to express different chondrogenic factors. DESIGN: Human MSCs derived from bone-marrow of osteoarthritis (OA) hips were genetically modified using adenoviral vectors encoding sex-determining region Y-type high-mobility-group-box (SOX) 9, transforming growth factor beta (TGFB) 1 or bone morphogenetic protein (BMP) 2 cDNA, placed in type I collagen hydrogels and maintained in serum-free chondrogenic media for three weeks. Control constructs contained unmodified MSCs or MSCs expressing GFP. The respective constructs were analyzed histologically, immunohistochemically, biochemically, and by qRT-PCR for chondrogenesis and hypertrophy. RESULTS: Chondrogenesis in MSCs was consistently and strongly induced in collagen I hydrogels by the transgenes SOX9, TGFB1 and BMP2 as evidenced by positive staining for proteoglycans, chondroitin-4-sulfate (CS4) and collagen (COL) type II, increased levels of glycosaminoglycan (GAG) synthesis, and expression of mRNAs associated with chondrogenesis. The control groups were entirely non-chondrogenic. The levels of hypertrophy, as judged by expression of alkaline phosphatase (ALP) and COL X on both the protein and mRNA levels revealed different stages of hypertrophy within the chondrogenic groups (BMP2>TGFB1>SOX9). CONCLUSIONS: Different types of neocartilage with varying levels of hypertrophy could be generated from human MSCs in collagen hydrogels by transfer of genes encoding the chondrogenic factors SOX9, TGFB1 and BMP2. This technology may be harnessed for regeneration of specific zones of native cartilage upon damage.


Assuntos
Proteína Morfogenética Óssea 2/genética , Hidrogéis/química , Fatores de Transcrição SOX9/genética , Fator de Crescimento Transformador beta1/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Cartilagem/citologia , Cartilagem/metabolismo , Cartilagem/patologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrogênese/genética , Colágeno Tipo I/química , Colágeno Tipo X/genética , Meios de Cultura Livres de Soro/química , Glicosaminoglicanos/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoartrite/metabolismo , Osteoartrite/patologia , RNA Mensageiro/metabolismo , Fatores de Transcrição SOX9/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
Environ Toxicol ; 35(12): 1318-1325, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32656944

RESUMO

In this study, we report the potential of cannabidiol, one of the major cannabis constituents, for enhancing osteoblastic differentiation in U2OS and MG-63 cells. Cannabidiol increased the expression of Angiopoietin1 and the enzyme activity of alkaline phosphatase in U2OS and MG-63. Invasion and migration assay results indicated that the cell mobility was activated by cannabidiol in U2OS and MG-63. Western blotting analysis showed that the expression of tight junction related proteins such as Claudin1, Claudin4, Occuludin1, and ZO1 was increased by cannabidiol in U2OS and MG-63. Alizarin Red S staining analysis showed that calcium deposition and mineralization was enhanced by cannabidiol in U2OS and MG-63. Western blotting analysis indicated that the expression of osteoblast differentiation related proteins such as distal-less homeobox 5, bone sialoprotein, osteocalcin, type I collagen, Runt-related transcription factor 2 (RUNX2), osterix (OSX), and alkaline phosphatase was time dependently upregulated by cannabidiol in U2OS and MG-63. Mechanistically, cannabidiol-regulated osteoblastic differentiation in U2OS and MG-63 by strengthen the protein-protein interaction among RUNX2, OSX, or the phosphorylated p38 mitogen-activated protein kinase (MAPK). In conclusion, cannabidiol increased Angiopoietin1 expression and p38 MAPK activation for osteoblastic differentiation in U2OS and MG-63 suggesting that cannabidiol might provide a novel therapeutic option for the bone regeneration.


Assuntos
Angiopoietina-1/metabolismo , Canabidiol/farmacologia , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Fosfatase Alcalina/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Humanos , Osteoblastos/citologia , Osteoblastos/metabolismo , Fosforilação
6.
Nature ; 583(7816): 425-430, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612231

RESUMO

The vascular interface of the brain, known as the blood-brain barrier (BBB), is understood to maintain brain function in part via its low transcellular permeability1-3. Yet, recent studies have demonstrated that brain ageing is sensitive to circulatory proteins4,5. Thus, it is unclear whether permeability to individually injected exogenous tracers-as is standard in BBB studies-fully represents blood-to-brain transport. Here we label hundreds of proteins constituting the mouse blood plasma proteome, and upon their systemic administration, study the BBB with its physiological ligand. We find that plasma proteins readily permeate the healthy brain parenchyma, with transport maintained by BBB-specific transcriptional programmes. Unlike IgG antibody, plasma protein uptake diminishes in the aged brain, driven by an age-related shift in transport from ligand-specific receptor-mediated to non-specific caveolar transcytosis. This age-related shift occurs alongside a specific loss of pericyte coverage. Pharmacological inhibition of the age-upregulated phosphatase ALPL, a predicted negative regulator of transport, enhances brain uptake of therapeutically relevant transferrin, transferrin receptor antibody and plasma. These findings reveal the extent of physiological protein transcytosis to the healthy brain, a mechanism of widespread BBB dysfunction with age and a strategy for enhanced drug delivery.


Assuntos
Envelhecimento/metabolismo , Envelhecimento/patologia , Barreira Hematoencefálica/metabolismo , Transcitose , Fosfatase Alcalina/metabolismo , Animais , Anticorpos/metabolismo , Transporte Biológico , Proteínas Sanguíneas/administração & dosagem , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/farmacocinética , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Saúde , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasma/metabolismo , Proteoma/administração & dosagem , Proteoma/metabolismo , Proteoma/farmacocinética , Receptores da Transferrina/imunologia , Transcrição Genética , Transferrina/metabolismo
7.
Int J Nanomedicine ; 15: 4471-4481, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606689

RESUMO

Background: Ineffective integration has been recognized as one of the major causes of early orthopedic failure of titanium-based implants. One strategy to address this problem is to develop modified titanium surfaces that promote osteoblast differentiation. This study explored titanium surfaces modified with TiO2 nanotubes (TiO2 NTs) capable of localized drug delivery into bone and enhanced osteoblast cell differentiation. Materials and Methods: Briefly, TiO2 NTs were subjected to anodic oxidation and loaded with Metformin, a widely used diabetes drug. To create surfaces with sustainable drug-eluting characteristics, TiO2 NTs were spin coated with a thin layer of chitosan. The surfaces were characterized via scanning electron microscopy, atomic force microscopy, and contact angle measurements. The surfaces were then exposed to mesenchymal bone marrow stem cells (MSCs) to evaluate cell adhesion, growth, differentiation, and morphology on the modified surfaces. Results: A noticeable increase in drug release time (3 days vs 20 days) and a decrease in burst release characteristics (85% to 7%) was observed in coated samples as compared to uncoated samples, respectively. Chitosan-coated TiO2 NTs exhibited a considerable enhancement in cell adhesion, proliferation, and genetic expression of type I collagen, and alkaline phosphatase activity as compared to uncoated TiO2 NTs. Conclusion: TiO2 NT surfaces with a chitosan coating are capable of delivering Metformin to a bone site over a sustained period of time with the potential to enhance MSCs cell attachment, proliferation, and differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Quitosana/química , Liberação Controlada de Fármacos , Metformina/farmacologia , Nanotubos/química , Osteoblastos/citologia , Titânio/química , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanotubos/ultraestrutura , Osteoblastos/efeitos dos fármacos , Osteoblastos/ultraestrutura , Osteogênese/efeitos dos fármacos , Ratos Wistar , Molhabilidade
8.
Gene ; 754: 144855, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32522695

RESUMO

Alkaline phosphatase (ALP) is highly expressed in the cells of mineralized tissue and plays a critical function in the formation of hard tissue. The existing status of this critical enzyme should be reviewed periodically. ALP increases inorganic phosphate local rates and facilitates mineralization as well as reduces the extracellular pyrophosphate concentration, an inhibitor of mineral formation. Mineralization is the production, inside matrix vesicles, of hydroxyapatite crystals that bud from the outermembrane of hypertrophic osteoblasts and chondrocytes. The expansion of hydroxyapatite formsinto the extracellular matrix and its accumulation between collagen fibrils is observed. Among various isoforms, the tissue-nonspecific isozyme of ALP (TNAP) is strongly expressed in bone, liver and kidney and plays a key function in the calcification of bones. TNAP hydrolyzes pyrophosphate and supplies inorganic phosphate to enhance mineralization. The biochemical substrates of TNAP are believed to be inorganic pyrophosphate and pyridoxal phosphate. These substrates concentrate in TNAP deficient condition which results in hypophosphatasia. The increased level of ALP expression and development in this environment would undoubtedly provide new and essential information about the fundamental molecular mechanisms of bone formation, offer therapeutic possibilities for the management of bone-related diseases.


Assuntos
Fosfatase Alcalina/química , Fosfatase Alcalina/metabolismo , Calcificação Fisiológica , Hipofosfatasia/patologia , Fosfatase Alcalina/deficiência , Animais , Humanos , Hipofosfatasia/enzimologia , Isoenzimas
9.
Int J Nanomedicine ; 15: 3523-3537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547011

RESUMO

Background: Patients with diabetes mellitus (DM) have a higher failure rate of dental implant treatments. However, whether titanium (Ti) implants with TiO2 nanotubes (TNT) surface can retain their biocompatibility and osteogenetic ability under DM conditions has not been investigated; in addition, their behavior in DM conditions is not well characterized. Materials and Methods: Pure Ti discs were surface treated into the polishing (mechanically polished, MP), sandblasted and acid-etched (SLA), and TNT groups. Scanning electron microscopy was used to examine the surface morphology. The cell adhesion and proliferation ability on different modified Ti surfaces at various glucose concentrations (5.5, 11, 16.5, and 22 mM) was detected by the CCK-8 assay. The osteogenetic ability on different modified Ti surfaces under high-glucose conditions was evaluated by alkaline phosphatase (ALP), osteopontin (OPN) immunofluorescence, Western blot, and Alizarin Red staining in vitro. Detection of cell apoptosis and intracellular reactive oxygen species (ROS) was undertaken both before and after N-acetylcysteine (NAC) treatment to assess the oxidative stress associated with different modified Ti surfaces under high-glucose conditions. An in vivo study was conducted in DM rats with different modified Ti femoral implants. The osteogenetic ability of different modified Ti implants in DM rats was assessed using a micro-CT scan. Results: High-glucose conditions inhibited cell adhesion, proliferation, and osteogenetic ability of different modified Ti surfaces. High-glucose conditions induced higher apoptosis rate and intracellular ROS level on different modified Ti surfaces; these effects were alleviated by NAC. Compared with the SLA surface, the TNT surface alleviated the osteogenetic inhibition induced by high-glucose states by reversing the overproduction of ROS in vitro. In the in vivo experiment, micro-CT scan analysis further confirmed the best osteogenetic ability of TNT surface in rats with DM. Conclusion: TNT surface modification alleviates osteogenetic inhibition induced by DM. It may provide a more favorable Ti implant surface for patients with DM.


Assuntos
Diabetes Mellitus/patologia , Nanotubos/química , Osteogênese/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Glucose/toxicidade , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Osteopontina/metabolismo , Próteses e Implantes , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Propriedades de Superfície
10.
Life Sci ; 256: 117908, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512011

RESUMO

BACKGROUND: Excessive alcohol intake contributes to severe liver damage involving oxidative stress and inflammatory responses, which make them promising therapeutic targets. Previous studies have demonstrated that empagliflozin (EMPA) showed cardiovascular, renal, and cerebral benefits potentially mediated through its antioxidant and anti-inflammatory actions. AIMS: This experiment aimed to evaluate the hepatoprotective effect of EMPA on alcoholic liver disease (ALD) and the possible underlying mechanisms. MATERIALS AND METHODS: Serum biochemical parameters and the liver contents of malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), and superoxide dismutase (SOD) were measured. Real-time qPCR was conducted to determine the gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ), nuclear factor erythroid 2-related factor 2 (Nrf-2), and heme oxygenase-1 (Hmox-1). In addition, ELISA was performed to measure tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, Nrf-2, and PPAR-γ. Nuclear factor-kappa B (NF-κB) was detected by immunohistochemical staining using an anti-NF-κB p65 antibody. KEY FINDINGS: Our results revealed that the serum levels of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase were significantly reduced by EMPA. EMPA also decreased the content of MDA and NO and increased the activities of SOD and GSH in liver homogenates. Moreover, EMPA inhibited the release of proinflammatory cytokines, including TNF-α, IL-1ß, and IL-6, via the downregulation of NF-κB. These changes were associated with an improvement in histopathological deterioration. The protective effect of EMPA against oxidative stress and inflammation was associated with the upregulation of PPAR-γ, Nrf-2, and their target gene Hmox-1. SIGNIFICANCE: EMPA showed protective activities against ethanol-induced liver injury by suppressing inflammation and oxidative stress via modulation of the NF-κB/Nrf-2/PPAR-γ axis.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Compostos Benzidrílicos/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/prevenção & controle , Fator de Transcrição de Proteínas de Ligação GA/metabolismo , Glucosídeos/farmacologia , NF-kappa B/metabolismo , PPAR gama/metabolismo , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Aspartato Aminotransferases/metabolismo , Compostos Benzidrílicos/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Descoberta de Drogas , Etanol/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/metabolismo , Glutationa/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Interleucinas/metabolismo , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/genética , Superóxido Dismutase/metabolismo
11.
Eur J Gastroenterol Hepatol ; 32(9): 1244-1250, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32568805

RESUMO

Coronoviraus disease 2019 (COVID-19) has infected over two million people worldwide and the number keeps growing every day. While the pulmonary complications of COVID-19 are obvious, the effect of the virus on the other organs and the chronicity of the organ dysfunction remain unknown. The virus causes a debilitating infection with multiorgan injury and has a high mortality rate estimated to be around 3.70%. Several hypotheses are formulated to explain the liver dysfunction in COVID-19 patients which include collateral damage from cytokine storm, drug-induced liver injury, viral-induced hepatitis and hypoxia-induced damage. Through this case series, we would like to highlight that liver enzyme abnormalities are often seen in COVID-19 patients and would like to highlight that physicians need to serially monitor biochemical testing until the liver enzymes return to baseline. Physicians also need to be vigilant of liver enzyme abnormalities in these patients, especially before starting new medications.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/enzimologia , Hepatopatias/etiologia , Pneumonia Viral/complicações , Pneumonia Viral/enzimologia , Adulto , Idoso , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Aspartato Aminotransferases/metabolismo , Feminino , Humanos , Masculino , Pandemias
12.
Travel Med Infect Dis ; 36: 101782, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32526372

RESUMO

INTRODUCTION: There are currently no satisfactory methods for predicting the outcome of Coronavirus Disease-2019 (COVID-19). The aim of this study is to establish a model for predicting the prognosis of the disease. METHODS: The laboratory results were collected from 54 deceased COVID-19 patients on admission and before death. Another 54 recovered COVID-19 patients were enrolled as control cases. RESULTS: Many laboratory indicators, such as neutrophils, AST, γ-GT, ALP, LDH, NT-proBNP, Hs-cTnT, PT, APTT, D-dimer, IL-2R, IL-6, IL-8, IL-10, TNF-α, CRP, ferritin and procalcitonin, were all significantly increased in deceased patients compared with recovered patients on admission. In contrast, other indicators such as lymphocytes, platelets, total protein and albumin were significantly decreased in deceased patients on admission. Some indicators such as neutrophils and procalcitonin, others such as lymphocytes and platelets, continuously increased or decreased from admission to death in deceased patients respectively. Using these indicators alone had moderate performance in differentiating between recovered and deceased COVID-19 patients. A model based on combination of four indicators (P = 1/[1 + e-(-2.658+0.587×neutrophils - 2.087×lymphocytes - 0.01×platelets+0.004×IL-2R)]) showed good performance in predicting the death of COVID-19 patients. When cutoff value of 0.572 was used, the sensitivity and specificity of the prediction model were 90.74% and 94.44%, respectively. CONCLUSIONS: Using the current indicators alone is of modest value in differentiating between recovered and deceased COVID-19 patients. A prediction model based on combination of neutrophils, lymphocytes, platelets and IL-2R shows good performance in predicting the outcome of COVID-19.


Assuntos
Infecções por Coronavirus/mortalidade , Pneumonia Viral/mortalidade , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/metabolismo , Aspartato Aminotransferases/metabolismo , Betacoronavirus , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Infecções por Coronavirus/sangue , Infecções por Coronavirus/metabolismo , Feminino , Ferritinas/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , L-Lactato Desidrogenase/metabolismo , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Peptídeo Natriurético Encefálico/metabolismo , Neutrófilos , Pandemias , Tempo de Tromboplastina Parcial , Fragmentos de Peptídeos/metabolismo , Pneumonia Viral/sangue , Pneumonia Viral/metabolismo , Pró-Calcitonina/metabolismo , Prognóstico , Tempo de Protrombina , Curva ROC , Receptores de Interleucina-2/metabolismo , Troponina T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , gama-Glutamiltransferase/metabolismo
13.
Gene ; 757: 144852, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32599019

RESUMO

Until now, various methods have been introduced to fabricate 3D scaffolds to provide a suitable substrate for cell growth and proliferation and subsequent use in tissue engineering to repair damaged tissues. The 3D scaffolds can simulate the natural cellular microenvironment well. Herein, the decellularized leaf spinach has been used which not only have no problems associated with artificial scaffolds, but they also do not cost significantly. Decellularized scaffolds surface properties were characterized by the investigation of scaffolds surface roughness, hydrophilicity, mechanical properties, size and shape of porosities and specific surface area. In the next step, osteogenic differentiation potential of bone marrow derived mesenchymal stem cells cultured on the scaffold and culture plate (as a control) was evaluated using alizarin staining and calcium content, alkaline phosphatase activity and bone related genes expression assays. The results indicated that the surface properties and shape of scaffold pores were effective in the stem cells binding, growth and proliferation. This higher biocompatibility due to the ideal surface hydrophilicity as well as high specific surface area due to the presence of a rough grid surface ultimately increased the efficiency of stem cell's bone differentiation. Taken together, it can be concluded that the decellularized spinach leaf scaffold, due to its easy availability, low prices and high efficiency, can be considered as a promising potential candidate for use as a proper substrate for stem cell growth and differentiation in bone tissue engineering.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Osteocalcina/genética , Folhas de Planta/química , Tecidos Suporte/química , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Biomineralização , Cálcio/metabolismo , Linhagem Celular , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteocalcina/metabolismo , Spinacia oleracea/química
14.
Cardiovasc Eng Technol ; 11(3): 316-327, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32356274

RESUMO

PURPOSE: Fibrocalcific aortic valve disease (CAVD) is caused by the deposition of calcific nodules in the aortic valve leaflets, resulting in progressive loss of function that ultimately requires surgical intervention. This process is actively mediated by the resident valvular interstitial cells (VICs), which, in response to oxidized lipids, transition from a quiescent to an osteoblast-like state. The purpose of this study was to examine if the ryanodine receptor, an intracellular calcium channel, could be therapeutically targeted to prevent this phenotypic conversion. METHODS: The expression of the ryanodine receptor in porcine aortic VICs was characterized by qRT-PCR and immunofluorescence. Next, the VICs were exposed to lysophosphatidylcholine, an oxidized lipid commonly found in low-density lipoprotein, while the activity of the ryanodine receptor was modulated with ryanodine. The cultures were analyzed for markers of cellular mineralization, alkaline phosphatase activity, proliferation, and apoptosis. RESULTS: Porcine aortic VICs predominantly express isoform 3 of the ryanodine receptors, and this protein mediates the cellular response to LPC. Exposure to LPC caused elevated intracellular calcium concentration in VICs, raised levels of alkaline phosphatase activity, and increased calcific nodule formation, but these changes were reversed when the activity of the ryanodine receptor was blocked. CONCLUSIONS: Our findings suggest blocking the activity of the ryanodine receptor can attenuate the valvular mineralization caused by LPC. We conclude that oxidized lipids, such as LPC, play an important role in the development and progression of CAVD and that the ryanodine receptor is a promising target for pharmacological intervention.


Assuntos
Valva Aórtica/efeitos dos fármacos , Calcinose/induzido quimicamente , Agonistas dos Canais de Cálcio/toxicidade , Cálcio/metabolismo , Lisofosfatidilcolinas/toxicidade , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Apoptose/efeitos dos fármacos , Calcinose/metabolismo , Calcinose/patologia , Calcinose/prevenção & controle , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Sus scrofa
15.
Life Sci ; 254: 117770, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32407846

RESUMO

AIMS: Cadmium chloride has various industrial applications and considered an industrial and environmental pollutant. The aim of this study was to evaluate the effect of atorvastatin on Cadmium chloride-induced hepatotoxicity in male rats. MATERIALS AND METHODS: Fifty-six adult male rats, randomly were divided into 8 groups. Groups 1-3 were received atorvastatin (20 mg/kg) intragastrically for 15 days during which Cadmium chloride (1, 2, and 3 mg/kg) were given intraperitoneally from days 8 to 15. Groups 4-6 were as first three groups but animals were received vehicle of atorvastatin. Group 7 was received vehicle of atorvastatin and vehicle of Cadmium chloride and Group 8 was received atorvastatin and vehicle of Cadmium chloride according to timeline of other groups. On day 16, under full anesthesia, blood sampling was prepared from heart, and livers were dissected out to analyses the biochemical and histopathology studies. KEY FINDINGS: Cadmium chloride significantly increased aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) in the serum. Malondialdehyde (MDA) significantly increased and superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH) significantly decreased the in the liver following Cadmium chloride administration. Atorvastatin significantly improved the levels of MDA, SOD, GPx, GSH, but not ALT, AST, and ALP in Cadmium chloride-treated rats. In histopathological studies, atorvastatin could not improve injured liver tissues induced by Cadmium chloride. SIGNIFICANCE: Atorvastatin has beneficial effects in improving Cadmium chloride-induced antioxidative enzymes disturbance which may be contribute to improving liver function in male rats.


Assuntos
Atorvastatina/farmacologia , Alanina Transaminase/sangue , Fosfatase Alcalina/metabolismo , Animais , Antioxidantes/farmacologia , Aspartato Aminotransferases/sangue , Atorvastatina/metabolismo , Cádmio/toxicidade , Cloreto de Cádmio/efeitos adversos , Cloreto de Cádmio/farmacologia , Cloreto de Cádmio/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
16.
Int J Nanomedicine ; 15: 2633-2646, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368045

RESUMO

Objective: The aim of this study is to fabricate functional scaffolds to gene delivery bone morphogenetic protein-2 (BMP-2) plasmid for bone formation in bone tissue engineering. Methods: Dendriplexes (DPs) of generation 4 polyamidoamin (G4-PAMAM)/BMP-2 plasmid were prepared through microfluidic (MF) platform. The physiochemical properties and toxicity of DPs were evaluated by DLS, AFM, FESEM and MTT assay. In order to create a suitable environment for stem cell growth and differentiation, poly-l-lactic acid (PLLA) and poly-l-lactic acid/poly (ethylene oxide) (PLLA/PEO) scaffolds containing hydroxyapatite nanoparticles (HA) and DPs were fabricated by the electrospinning method. The osteogenic potency of the scaffolds on human adipose tissue-derived mesenchymal stem cells (hASCs) was investigated. Results: The results revealed that tuning the physical properties of DPs by adjusting flow parameters in microfluidic platform can easily improve the cell viability compared to conventional bulk mixing method. Also, the result showed that the presence of HA and DPs in PLLA/PEO scaffold enhanced alkaline phosphatase (ALP) activity and increased the amount of deposited Ca, as well as, related to osteogenesis gen markers. Conclusion: This study indicated that on using the MF platform in preparation of DPs and loading them along with HA in PLLA/PEO scaffold, the osteogenic differentiation of hASCs could be tuned.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Osso e Ossos/fisiologia , Durapatita/química , Microfluídica , Nanofibras/química , Poliaminas/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Adesão Celular , Morte Celular , Diferenciação Celular , Proliferação de Células , Forma Celular , DNA/metabolismo , Dendrímeros/química , Humanos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Tamanho da Partícula , Plasmídeos/metabolismo , Poliésteres/química , Resistência à Tração
17.
Int J Nanomedicine ; 15: 3281-3290, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440124

RESUMO

Introduction: Cells exhibit high sensitivity and a diverse response to the nanotopography of the extracellular matrix, thereby endowing materials with instructive performances formerly reserved for growth factors. This finding leads to opportunities for improvement. However, the interplay between the topographical surface and cell behaviors remains incompletely understood. Methods: In the present study, we showed nanosurfaces with various dimensions of nanopits (200-750 nm) fabricated by self-assembling polystyrene (PS) nanospheres. Human adipose-derived stem cell behaviors, such as cell morphology, adhesion, cytoskeleton contractility, proliferation, and differentiation, were investigated on the prepared PS nanopit surface. Results: The osteogenic differentiation can be enhanced by nanopits with a diameter of 300-400 nm. Discussion: The present study provided exciting new avenues to investigate cellular responses to well-defined nanoscale topographic features, which could further guide bone tissue engineering and stem cell clinical research. The capability to control developing biomaterials mimicking nanotopographic surfaces promoted functional tissue engineering, such as artificial joint replacement, bone repair, and dental applications.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Nanoestruturas/química , Osteogênese , Poliestirenos/farmacologia , Células-Tronco/citologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Nanoestruturas/ultraestrutura , Osteogênese/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/ultraestrutura
18.
Arterioscler Thromb Vasc Biol ; 40(7): 1680-1694, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32375544

RESUMO

OBJECTIVE: The recessive disease arterial calcification due to deficiency of CD73 (ACDC) presents with extensive nonatherosclerotic medial layer calcification in lower extremity arteries. Lack of CD73 induces a concomitant increase in TNAP (tissue nonspecific alkaline phosphatase; ALPL), a key enzyme in ectopic mineralization. Our aim was to investigate how loss of CD73 activity leads to increased ALPL expression and calcification in CD73-deficient patients and assess whether this mechanism may apply to peripheral artery disease calcification. Approach and Results: We previously developed a patient-specific disease model using ACDC primary dermal fibroblasts that recapitulates the calcification phenotype in vitro. We found that lack of CD73-mediated adenosine signaling reduced cAMP production and resulted in increased activation of AKT. The AKT/mTOR (mammalian target of rapamycin) axis blocks autophagy and inducing autophagy prevented calcification; however, we did not observe autophagy defects in ACDC cells. In silico analysis identified a putative FOXO1 (forkhead box O1 protein) binding site in the human ALPL promoter. Exogenous AMP induced FOXO1 nuclear localization in ACDC but not in control cells, and this was prevented with a cAMP analogue or activation of A2a/2b adenosine receptors. Inhibiting FOXO1 reduced ALPL expression and TNAP activity and prevented calcification. Mutating the FOXO1 binding site reduced ALPL promoter activation. Importantly, we provide evidence that non-ACDC calcified femoropopliteal arteries exhibit decreased CD73 and increased FOXO1 levels compared with control arteries. CONCLUSIONS: These data show that lack of CD73-mediated cAMP signaling promotes expression of the human ALPL gene via a FOXO1-dependent mechanism. Decreased CD73 and increased FOXO1 was also observed in more common peripheral artery disease calcification.


Assuntos
5'-Nucleotidase/deficiência , Fibroblastos/enzimologia , Proteína Forkhead Box O1/metabolismo , Doença Arterial Periférica/enzimologia , Artéria Poplítea/enzimologia , Calcificação Vascular/enzimologia , 5'-Nucleotidase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Autofagia , Estudos de Casos e Controles , Células Cultivadas , Feminino , Fibroblastos/patologia , Proteína Forkhead Box O1/genética , Proteínas Ligadas por GPI/deficiência , Proteínas Ligadas por GPI/genética , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/genética , Doença Arterial Periférica/patologia , Artéria Poplítea/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/patologia , Adulto Jovem
19.
J Bone Miner Metab ; 38(5): 670-677, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32415375

RESUMO

INTRODUCTION: The periosteum has a bilayered structure that surrounds cortical bone. The outer layer is rich in connective tissue and fibroblasts, while the inner layer in contact with the cortical surface of the bone predominantly consists of osteoblasts and osteoblast progenitors. The identification of cell-specific surface markers of the bilayered structure of the periosteum is important for the purpose of tissue regeneration. MATERIALS AND METHODS: We investigated the expression of the discoidin domain tyrosine kinase receptor DDR2, fibroblast specific protein-1 (FSP-1) and alkaline phosphatase (ALP) in the periosteum of cortical bone by immunohistochemistry. Osteogenic differentiation was compared between DDR2- and FSP-1-expressing cells flow-sorted from the periosteum. RESULTS: We showed that DDR2 predominantly labeled osteogenic cells residing in the inner layer of the periosteum and that Pearson's coefficient of colocalization indicated a significant correlation with the expression of ALP. The mineralization of DDR2-expressing osteogenic cells isolated from the periosteum was significantly induced. In contrast, FSP-1 predominantly labeled the outer layer of periosteal fibroblasts, and Pearson's coefficient of colocalization indicated that FSP-1 was poorly correlated with the expression of DDR2 and ALP. FSP-1-expressing periosteal fibroblasts did not exhibit osteogenic differentiation for the induction of bone mineralization. CONCLUSION: DDR2 is a novel potential cell surface marker for identifying and isolating osteoblasts and osteoblast progenitors within the periosteum that can be used for musculoskeletal regenerative therapies.


Assuntos
Receptores com Domínio Discoidina/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Periósteo/citologia , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica , Diferenciação Celular , Camundongos Endogâmicos C57BL , Osteogênese , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo
20.
BMC Oral Health ; 20(1): 125, 2020 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-32334598

RESUMO

BACKGROUND: Bisphosphonate coating of dental implants is a promising tool for surface modification aiming to improve the osseointegration process and clinical outcome. The biological effects of bisphosphonates are thought to be mainly associated with osteoclasts inhibition, whereas their effects on osteoblast function are unclear. A potential of bisphosphonate coated surfaces to stimulate osteoblast differentiation was investigated by several in vitro studies with contradictory results. The purpose of this systematic review and meta-analysis was to evaluate the effect of bisphosphonate coated implant surfaces on alkaline phosphatase activity in osteoblasts. METHODS: In vitro studies that assessed alkaline phosphatase activity in osteoblasts following cell culture on bisphosphonate coated titanium surfaces were searched in electronic databases PubMed/MEDLINE, Scopus and ISI Web of Science. Animal studies and clinical trials were excluded. The literature search was restricted to articles written in English and published up to August 2019. Publication bias was assessed by the construction of funnel plots. RESULTS: Eleven studies met the inclusion criteria. Meta-analysis showed that coating of titanium surfaces with bisphosphonates increases alkaline phosphatase activity in osteoblasts after 3 days (n = 1), 7 (n = 7), 14 (n = 6) and 21 (n = 3) days. (7 days beta coefficient = 1.363, p-value = 0.001; 14 days beta coefficient = 1.325, p-value < 0.001; 21 days beta coefficient = 1.152, p-value = 0.159). CONCLUSIONS: The meta-analysis suggests that bisphosphonate coatings of titanium implant surfaces may have beneficial effects on osteogenic behaviour of osteoblasts grown on titanium surfaces in vitro. Further studies are required to assess to which extent bisphosphonates coating might improve osseointegration in clinical situations.


Assuntos
Fosfatase Alcalina/farmacologia , Implantes Dentários , Difosfonatos/farmacologia , Osseointegração/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Propriedades de Superfície , Titânio/química
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