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1.
J Appl Toxicol ; 43(6): 772-788, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36301730

RESUMO

Abnormal ovarian function is the main manifestation of female reproductive toxicity. Granulosa cells (GCs) play an important role in determining the fate of follicles and are the main effector cells of the female reproductive system. Excessive apoptosis of GCs leads to pathological folliculogenesis and further reproductive damage. However, drugs available for treatment of female reproductive toxicity are limited. Recent studies have confirmed that various natural products and bioactive ingredients of traditional Chinese medicine (TCM) can inhibit apoptosis of GCs and protect ovarian function. In this review, the mechanisms underlying the proapoptotic and antiapoptotic effects of natural products and bioactive ingredients of TCM on the proliferation, function, and apoptosis of GCs are summarized based on the findings of reports published over the past 10 years as reference for the treatment of female reproductive toxicity.


Assuntos
Medicina Tradicional Chinesa , Folículo Ovariano , Feminino , Humanos , Células da Granulosa , Apoptose
2.
J Environ Manage ; 329: 117012, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36608618

RESUMO

Woody plant encroachment has been long observed in the southern Great Plains (SGP) of the United States. However, our understanding of its spatiotemporal variability, which is the basis for informed and targeted management strategy, is still poor. This study investigates the encroachment of evergreen forest, which is the most important encroachment component in the SGP. A validated evergreen forest map of the SGP (30 m resolution, for the time period 2015 to 2017) from our previous study was utilized (referred to as evergreen_base). Sample plots of evergreen forest (as of 2017) were collected across the study area, based on which a threshold of winter season (January and February) mean normalized difference vegetation index (NDVIwinter) was derived for each of the 5 sub-regions, using Landsat 7 surface reflectance data from 2015 to 2017. Then a NDVIwinter layer was created for each year within the four time periods of 1985-1989, 1995-1999, 2005-2009, and 2015-2017, with winter season surface reflectance data from Landsat 4, 5, and 7. By applying the sub-region specific NDVIwinter thresholds to the annual NDVIwinter layers and the evergreen_base, a SGP evergreen forest map was generated for each of those years. The annual evergreen forest maps within each time period were composited into one. According to the resulting four composite evergreen forest maps, mean annual encroachment rate (km2/year) was calculated at sub-region and ecoregion scales, over each of the three temporal stages 1990-1999, 2000-2009, and 2010-2017, respectively. To understand the spatiotemporal variability of the encroachment, the encroachment rate at each temporal stage was related to the corresponding initial evergreen forest area, mean annual precipitation (MAP), and mean annual burned area (MABA) through linear regression and pairwise comparison. Results suggest that most of the ecoregions have seen a slowing trend of evergreen forest encroachment since 1990. The temporal trend of encroachment rate tends to be consistent with that of MAP, but opposite to that of MABA. The spatial variability of the encroachment rate among ecoregions can be largely (>68%) explained by initial evergreen forest area but shows no significant relationship with MAP or MABA. These findings provide pertinent guidance for the combat of woody plant encroachment in the SGP under the context of climate change.


Assuntos
Florestas , Árvores , Plantas , Mudança Climática , Modelos Lineares
3.
Molecules ; 28(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175184

RESUMO

Protocatechuic acid (PCA) is a natural component with multiple biological activities. However, the underlying mechanisms of the effects of PCA on anti-ulcerative colitis (UC) are unclear. A UC mouse model was established by allowing the mice to freely drink a dextran sulfate sodium solution. The mice were administered PCA intragastrically for 7 days. Histological pathology, intestinal flora, and ferroptosis regulators were determined in vivo. Additionally, ferroptotic Caco-2 cells were modeled to investigate the role of PCA in ferroptosis. Our results showed that PCA reduced the levels of the disease activity index, inflammatory factors, and histological damage in UC mice. We also found that the regulation of intestinal flora, especially Bacteroidetes, was one of the potential mechanisms underlying the protective effects of PCA anti-UC. Moreover, PCA downregulated the level of ferroptosis in the colon tissue, as evidenced by a reduced iron overload, decreased glutathione depletion, and a lower level of malondialdehyde production compared with the model group. Similar effects of PCA on ferroptosis were observed in Erastin-treated Caco-2 cells. The results obtained using reactive oxygen species assays and the changes in mitochondrial structure observed via scanning electron microscopy also support these results. Our findings suggested that PCA protected against UC by regulating intestinal flora and ferroptosis.


Assuntos
Colite Ulcerativa , Colite , Ferroptose , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Dextranos/farmacologia , Células CACO-2 , Colite Ulcerativa/induzido quimicamente , Colo , Sulfatos/farmacologia , Sódio , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Colite/patologia , Camundongos Endogâmicos C57BL
4.
Cell Tissue Res ; 388(3): 565-581, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35362831

RESUMO

Epigenetics plays a critical role in regulating mesenchymal stem cells' (MSCs) fate for tissue repair and regeneration. There is increasing evidence that the inhibition of histone deacetylase (HDAC) isoform 3 can enhance MSC osteogenesis. This study investigated the potential of using a selective HDAC2 and 3 inhibitor, MI192, to promote human dental pulp stromal cells (hDPSCs) bone-like tissue formation in vitro and in vivo within porous Bombyx Mori silk scaffolds. Both 2 and 5 wt% silk scaffolds were fabricated and characterised. The 5 wt% scaffolds possess thicker internal lamellae, reduced scaffold swelling and degradation rates, whilst increased compressive modulus in comparison to the 2 wt% silk scaffold. MI192 pre-treatment of hDPSCs on 5 wt% silk scaffold significantly enhanced hDPSCs alkaline phosphatase activity (ALP). The expression of osteoblast-related genes (RUNX2, ALP, Col1a, OCN) was significantly upregulated in the MI192 pre-treated cells. Histological analysis confirmed that the MI192 pre-treated hDPSCs-silk scaffold constructs promoted bone extracellular matrix (ALP, Col1a, OCN) deposition and mineralisation compared to the untreated group. Following 6 weeks of subcutaneous implantation in nude mice, the MI192 pre-treated hDPSCs-silk scaffold constructs enhanced the vascularisation and extracellular matrix mineralisation compared to untreated control. In conclusion, these findings demonstrate the potential of using epigenetic reprogramming and silk scaffolds to promote hDPSCs bone formation efficacy, which provides evidence for clinical translation of this technology for bone augmentation.


Assuntos
Inibidores de Histona Desacetilases , Engenharia Tecidual , Animais , Benzamidas , Células Cultivadas , Polpa Dentária/metabolismo , Epigênese Genética , Inibidores de Histona Desacetilases/farmacologia , Humanos , Isoquinolinas , Camundongos , Camundongos Nus , Osteogênese/genética , Seda/farmacologia , Células Estromais/metabolismo , Alicerces Teciduais
5.
Pharm Biol ; 60(1): 501-508, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35188840

RESUMO

CONTEXT: The osteogenic potential of the human dental pulp stromal cells (hDPSCs) was reduced in the state of oxidative stress. Resveratrol (RSV) possesses numerous biological properties, including osteogenic potential, growth-promoting and antioxidant activities. OBJECTIVE: This study investigates the osteogenic potential of RSV by activating the Sirt1/Nrf2 pathway on oxidatively stressed hDPSCs and old mice. MATERIALS AND METHODS: The hDPSCs were subjected to reactive oxygen species (ROS) fluorescence staining, cell proliferation assay, ROS activity assay, superoxide dismutase (SOD) enzyme activity, the glutathione (GSH) concentration assay, alkaline phosphatase staining, real-time polymerase chain reaction (RT-PCR) and Sirt1 immunofluorescence labelling to assess the antioxidant stress and osteogenic ability of RSV. Forty female Kunming mice were divided into Old, Old-RSV, Young and Young-RSV groups to assess the repair of calvarial defects of 0.2 mL RSV of 20 mg/kg/d for seven days by injecting intraperitoneally at 4 weeks after surgery using micro-computed tomography, nonlinear optical microscope and immunohistochemical analysis. RESULTS: RSV abates oxidative stress by alleviating the proliferation, mitigating the ROS activity, increasing the SOD enzyme activity and ameliorating the GSH concentration (RSV IC50 in hDPSCs is 67.65 ± 9.86). The antioxidative stress and osteogenic capabilities of RSV were confirmed by the up-regulated gene expression of SOD1, xCT, RUNX2 and OCN, as well as Sirt1/Nrf2. The collagen, bone matrix formation and Sirt1 expression, are significantly increased after RSV treatment in mice. DISCUSSION AND CONCLUSIONS: For elderly or patients with oxidative stress physiological states such as hypertension, heart disease, diabetes, etc., RSV may potentially improve bone augmentation surgery in regenerative medicine.


Assuntos
Osteogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Células Estromais/efeitos dos fármacos , Fatores Etários , Animais , Animais não Endogâmicos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/citologia , Feminino , Humanos , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/metabolismo , Células Estromais/citologia , Superóxido Dismutase/metabolismo
6.
Stem Cells ; 38(3): 410-421, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31746084

RESUMO

In this study, we examined the Ca2+ -permeable Piezo1 channel, a newly identified mechanosensing ion channel, in human dental pulp-derived mesenchymal stem cells (MSCs) and hypothesized that activation of the Piezo1 channel regulates MSC migration via inducing ATP release and activation of the P2 receptor purinergic signaling. The Piezo1 mRNA and protein were readily detected in hDP-MSCs from multiple donors and, consistently, brief exposure to Yoda1, the Piezo1 channel-specific activator, elevated intracellular Ca2+ concentration. Yoda1-induced Ca2+ response was inhibited by ruthenium red or GsMTx4, two Piezo1 channel inhibitors, and also by Piezo1-specific siRNA. Brief exposure to Yoda1 also induced ATP release. Persistent exposure to Yoda1 stimulated MSC migration, which was suppressed by Piezo1-specific siRNA, and also prevented by apyrase, an ATP scavenger, or PPADS, a P2 generic antagonist. Furthermore, stimulation of MSC migration induced by Yoda1 as well as ATP was suppressed by PF431396, a PYK2 kinase inhibitor, or U0126, an inhibitor of the mitogen-activated protein kinase MEK/ERK signaling pathway. Collectively, these results suggest that activation of the Piezo1 channel stimulates MSC migration via inducing ATP release and subsequent activation of the P2 receptor purinergic signaling and downstream PYK2 and MEK/ERK signaling pathways, thus revealing novel insights into the molecular and signaling mechanisms regulating MSC migration. Such findings provide useful information for evolving a full understanding of MSC migration and homing and developing strategies to improve MSC-based translational applications.


Assuntos
Trifosfato de Adenosina/metabolismo , Canais Iônicos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Receptores Purinérgicos P2/metabolismo , Adulto , Movimento Celular , Criança , Feminino , Humanos , Masculino , Transdução de Sinais , Adulto Jovem
7.
Int J Mol Sci ; 22(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069280

RESUMO

The use of human dental pulp stromal cells (hDPSCs) has gained increasing attention as an alternative stem cell source for bone tissue engineering. The modification of the cells' epigenetics has been found to play an important role in regulating differentiation, with the inhibition of histone deacetylases 3 (HDAC3) being linked to increased osteogenic differentiation. This study aimed to induce epigenetic reprogramming using the HDAC2 and 3 selective inhibitor, MI192 to promote hDPSCs osteogenic capacity for bone regeneration. MI192 treatment caused a time-dose-dependent change in hDPSC morphology and reduction in viability. Additionally, MI192 successfully augmented hDPSC epigenetic functionality, which resulted in increased histone acetylation and cell cycle arrest at the G2/M phase. MI192 pre-treatment exhibited a dose-dependent effect on hDPSCs alkaline phosphatase activity. Quantitative PCR and In-Cell Western further demonstrated that MI192 pre-treatment significantly upregulated hDPSCs osteoblast-related gene and protein expression (alkaline phosphatase, bone morphogenic protein 2, type I collagen and osteocalcin) during osteogenic differentiation. Importantly, MI192 pre-treatment significantly increased hDPSCs extracellular matrix collagen production and mineralisation. As such, for the first time, our findings show that epigenetic reprogramming with the HDAC2 and 3 selective inhibitor MI192 accelerates the osteogenic differentiation of hDPSCs, demonstrating the considerable utility of this MSCs engineering approach for bone augmentation strategies.


Assuntos
Benzamidas/farmacologia , Polpa Dentária/citologia , Inibidores de Histona Desacetilases/farmacologia , Isoquinolinas/farmacologia , Osteogênese/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Benzamidas/administração & dosagem , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/administração & dosagem , Histonas/metabolismo , Humanos , Isoquinolinas/administração & dosagem , Dente Serotino/citologia , Osteogênese/fisiologia , Células Estromais/metabolismo
8.
Support Care Cancer ; 28(6): 2911-2919, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31758321

RESUMO

PURPOSE: Sleep disturbances are common in cancer patients, but little is known about preoperative insomnia and its associated factors in colorectal cancer (CRC) patients. The aim of this study was to clarify the relationship between preoperative insomnia and its associated factors (i.e., pain, anxiety, self-esteem, and coping styles) in CRC patients. METHODS: A cross-sectional study was conducted in consecutive CRC inpatients (N = 434), who were required to complete the questionnaires about insomnia, pain, anxiety, self-esteem, and coping styles (acceptance/resignation, confrontation, avoidance) before the day of surgery. Hierarchical regression analyses were conducted to explore the relationships between preoperative anxiety and its associated factors. RESULTS: Based on the cutoff value of Athens Insomnia Scale (scores ≥ 6) in Chinese cancer patients, the prevalence of insomnia was 38.2% before surgery. Pain (ß = 0.087, p = 0.015) and anxiety (ß = 0.372, p < 0.001) were positively associated with preoperative insomnia, while self-esteem (ß = - 0.479, p < 0.001) and confrontation coping (ß = - 0.124, p = 0.003) showed protective effects on preoperative insomnia when putting them together into hierarchical regression. The associated factors together accounted for an additional variance of preoperative insomnia (47.6%). CONCLUSIONS: In line with previous findings, the detrimental effects of pain and anxiety on preoperative insomnia were also observed in our study. More importantly, our main new findings were that self-esteem and confrontation coping played important roles in alleviating preoperative insomnia among CRC patients. Clinicians should take these results into account when developing cancer care management to relieve preoperative insomnia.


Assuntos
Ansiedade/epidemiologia , Dor do Câncer/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/psicologia , Neoplasias Colorretais/cirurgia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adaptação Psicológica/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/complicações , Ansiedade/psicologia , Povo Asiático/estatística & dados numéricos , Dor do Câncer/psicologia , Dor do Câncer/cirurgia , China/epidemiologia , Neoplasias Colorretais/complicações , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prevalência , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Inquéritos e Questionários
9.
J Transl Med ; 17(1): 327, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570111

RESUMO

BACKGROUND: Oxidative stress has a determinantal effect on human dental pulp stromal cells (hDPSCs), including affecting their longevity and functionality. Circular RNAs (circRNAs) play an essential role in stromal cell behavior; however, the exact mechanism in which circRNAs functions within hDPSCs were undergoing oxidative stress remains unclear. The purpose of this study is to assess the global changes and characteristics of circRNAs in hDPSCs undergoing oxidative stress. METHODS: Using an oxidative stress model of hDPSCs, we applied microarray analysis to examine the circRNAs profiles. We confirmed the changes in circRNAs by quantitative Real-Time PCR (qRT-PCR). Furthermore, bioinformatics tools, including a miRcode map, TargetScan, gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, were reconstructed for further assessment. SIRT1 gene and protein expression were tested by qRT-PCR and In Cell-Western analysis. RESULTS: We revealed 330 upregulated, and 533 downregulated circRNAs undergoing oxidative stress in hDPSCs and confirmed three circRNAs distinct expressions (hsa_circ_0000257, hsa_circ_0087354, and hsa_circ_0001946) in hDPSCs undergoing oxidative stress by qRT-PCR. GO, and KEGG pathway enrichment revealed the differentially expressed circRNAs might participate in p53 and cell cycle signaling networks associated with oxidative stress. SIRT1 gene and protein expression was reduced in the oxidatively stressed cells (OSC) group compared to untreated cells (UC). CONCLUSIONS: The findings of this study has provided new insights into circRNAs and a basis for further studies assessing the potential functions of hsa_circ_0000257, hsa_circ_0087354, and hsa_circ_0001946 in oxidatively stressed hDPSCs.


Assuntos
Polpa Dentária/patologia , Regulação da Expressão Gênica , Estresse Oxidativo , RNA Circular/metabolismo , Sequência de Bases , Forma Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Anotação de Sequência Molecular , Estresse Oxidativo/efeitos dos fármacos , RNA Circular/genética , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Células Estromais/patologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Adulto Jovem
10.
Cell Mol Life Sci ; 74(20): 3697-3710, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28534085

RESUMO

The ability of cells to migrate to the destined tissues or lesions is crucial for physiological processes from tissue morphogenesis, homeostasis and immune responses, and also for stem cell-based regenerative medicines. Cytosolic Ca2+ is a primary second messenger in the control and regulation of a wide range of cell functions including cell migration. Extracellular ATP, together with the cognate receptors on the cell surface, ligand-gated ion channel P2X receptors and a subset of G-protein-coupled P2Y receptors, represents common autocrine and/or paracrine Ca2+ signalling mechanisms. The P2X receptor ion channels mediate extracellular Ca2+ influx, whereas stimulation of the P2Y receptors triggers intracellular Ca2+ release from the endoplasmic reticulum (ER), and activation of both type of receptors thus can elevate the cytosolic Ca2+ concentration ([Ca2+]c), albeit with different kinetics and capacity. Reduction in the ER Ca2+ level following the P2Y receptor activation can further induce store-operated Ca2+ entry as a distinct Ca2+ influx pathway that contributes in ATP-induced increase in the [Ca2+]c. Mesenchymal stem cells (MSC) are a group of multipotent stem cells that grow from adult tissues and hold promising applications in tissue engineering and cell-based therapies treating a great and diverse number of diseases. There is increasing evidence to show constitutive or evoked ATP release from stem cells themselves or mature cells in the close vicinity. In this review, we discuss the mechanisms for ATP release and clearance, the receptors and ion channels participating in ATP-induced Ca2+ signalling and the roles of such signalling mechanisms in mediating ATP-induced regulation of MSC migration.


Assuntos
Trifosfato de Adenosina/metabolismo , Sinalização do Cálcio , Movimento Celular , Células-Tronco Mesenquimais/citologia , Animais , Cálcio/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Receptores Purinérgicos P2/metabolismo
11.
J Cell Physiol ; 232(2): 287-297, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27403750

RESUMO

Extracellular ATP and other nucleotides induce autocrine and/or paracrine purinergic signalling via activation of the P2 receptors on the cell surface, which represents one of the most common signalling mechanisms. Mesenchymal stem cells (MSC) are a type of multipotent adult stem cells that have many promising applications in regenerative medicine. There is increasing evidence to show that extracellular nucleotides regulate MSC functions and P2 receptor-mediated purinergic signalling plays an important role in such functional regulation. P2 receptors comprise ligand-gated ion channel P2X receptors and G-protein-coupled P2Y receptors. In this review, we provide an overview of the current understanding with respect to expression of the P2X and P2Y receptors in MSC and their roles in mediating extracellular nucleotide regulation of MSC proliferation, migration and differentiation. J. Cell. Physiol. 232: 287-297, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Espaço Extracelular/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nucleotídeos/metabolismo , Receptores Purinérgicos P2/metabolismo , Animais , Diferenciação Celular , Humanos , Células-Tronco Mesenquimais/citologia
12.
Stem Cells ; 34(8): 2102-14, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27038239

RESUMO

ATP is an extrinsic signal that can induce an increase in the cytosolic Ca(2+) level ([Ca(2+) ]c ) in mesenchymal stem cells (MSCs). However, the cognate intrinsic mechanisms underlying ATP-induced Ca(2+) signaling in MSCs is still contentious, and their importance in MSC migration remains unknown. In this study, we investigated the molecular mechanisms underlying ATP-induced Ca(2+) signaling and their roles in the regulation of cell migration in human dental pulp MSCs (hDP-MSCs). RT-PCR analysis of mRNA transcripts and interrogation of agonist-induced increases in the [Ca(2+) ]c support that P2X7, P2Y1 , and P2Y11 receptors participate in ATP-induced Ca(2+) signaling. In addition, following P2Y receptor activation, Ca(2+) release-activated Ca(2+) Orai1/Stim1 channel as a downstream mechanism also plays a significant role in ATP-induced Ca(2+) signaling. ATP concentration-dependently stimulates hDP-MSC migration. Pharmacological and genetic interventions of the expression or function of the P2X7, P2Y1 and P2Y11 receptors, and Orai1/Stim1 channel support critical involvement of these Ca(2+) signaling mechanisms in ATP-induced stimulation of hDP-MSC migration. Taken together, this study provide evidence to show that purinergic P2X7, P2Y1 , and P2Y11 receptors and store-operated Orai1/Stim1 channel represent important molecular mechanisms responsible for ATP-induced Ca(2+) signaling in hDP-MSCs and activation of these mechanisms stimulates hDP-MSC migration. Such information is useful in building a mechanistic understanding of MSC homing in tissue homeostasis and developing more efficient MSC-based therapeutic applications. Stem Cells 2016;34:2102-2114.


Assuntos
Trifosfato de Adenosina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Receptores Purinérgicos/metabolismo , Adulto , Criança , Polpa Dentária/citologia , Espaço Extracelular/metabolismo , Feminino , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Adulto Jovem
13.
Am J Pathol ; 185(1): 240-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25529795

RESUMO

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy with a poor prognosis due to its highly invasive and metastatic potential. The molecular pathogenesis underlying the invasive mechanism of ESCC is not well known because of the lack of existing models to study this disease. p120-Catenin (p120ctn) and the epidermal growth factor receptor (EGFR) have each been implicated in several cancers, including ESCC. p120ctn is down-regulated in 60% of ESCC tumors, whereas EGFR is the most commonly overexpressed oncogene in ESCC. For these reasons, we investigated the cooperation between p120ctn and EGFR and its effect on ESCC invasion. We show that p120ctn down-regulation is commonly associated with EGFR overexpression. By using a three-dimensional culture system, we demonstrate that the inverse relationship between p120ctn and EGFR has biological implications. Specifically, p120ctn down-regulation coupled with EGFR overexpression in human esophageal keratinocytes (EPC1-PE) was required to promote invasion. Morphological comparison of EPC1-PE cells grown in three-dimensional culture and human ESCC revealed identical features, including significantly increased cellularity, nuclear grade, and proliferation. Molecular characteristics were measured by keratin expression patterns, which were nearly identical between EPC1-PE cells in three-dimensional culture and ESCC samples. Altogether, our analyses have demonstrated that p120ctn down-regulation and EGFR overexpression are able to mimic human ESCC in a relevant three-dimensional culture model.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Cateninas/metabolismo , Receptores ErbB/metabolismo , Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Antígenos CD , Caderinas/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , Epitélio/metabolismo , Epitélio/patologia , Carcinoma de Células Escamosas do Esôfago , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Queratinas/metabolismo , Invasividade Neoplásica , delta Catenina
14.
Cytometry A ; 87(11): 1012-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26441162

RESUMO

There is growing interest in the development of methods capable of non-invasive characterization of stem cells prior to their use in cell-based therapies. Raman spectroscopy has previously been used to detect biochemical changes commensurate with the osteogenic, cardiogenic, and neurogenic differentiation of stem cells. The aim of this study was to characterize the adipogenic differentiation of live adipose derived stem cells (ASCs) under aseptic conditions. ASCs were cultured in adipogenic or basal culture medium for 14 days in customized culture flasks containing quartz windows. Raman spectra were acquired every 3 days. Principal component analysis (PCA) was used to identify spectral changes in the cultures over time. Adipogenic differentiation was confirmed using quantitative reverse transcription polymerase chain reaction for the marker genes PPARγ and ADIPOQ and Oil red O staining performed. PCA demonstrated that lipid associated spectral features varied throughout ASC differentiation with the earliest detection of the lipid associated peak at 1,438 cm(-1) after 3 days of induction. After 7 days of culture there were clear differences between the spectra acquired from ASCs in adipogenic or basal culture medium. No changes were observed in the spectra acquired from undifferentiated ASCs. Significant up-regulation in the expression of both PPARγ and ADIPOQ genes (P < 0.001) was observed after 14 days of differentiation as was prominent Oil red O staining. However, the Raman sampling process resulted in weaker gene expression compared with ASCs that had not undergone Raman analysis. This study demonstrated that Raman spectroscopy can be used to detect biochemical changes associated with adipogenic differentiation in a non-invasive and aseptic manner and that this can be achieved as early as three days into the differentiation process.


Assuntos
Adipócitos/citologia , Adipogenia/fisiologia , Tecido Adiposo/citologia , Células-Tronco/citologia , Adulto , Células Cultivadas , Humanos , Pessoa de Meia-Idade , Análise Espectral Raman/métodos , Células Estromais/citologia , Regulação para Cima
15.
Cell Tissue Res ; 361(2): 529-40, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25636587

RESUMO

The cell surface hydrolase tissue non-specific alkaline phosphatase (TNAP) (also known as MSCA-1) is used to identify a sub-population of bone marrow stromal cells (BMSCs) with high mineralising potential and is found on subsets of cells within the dental pulp. We aim to determine whether TNAP is co-expressed by human dental pulp stromal cells (hDPSCs) alongside a range of BMSC markers, whether this is an active form of the enzyme and the effects of culture duration and cell density on its expression. Cells from primary dental pulp and culture expanded hDPSCs expressed TNAP. Subsequent analyses revealed persistent TNAP expression and co-expression with BMSC markers such as CD73 and CD90. Flow cytometry and biochemical assays showed that increased culture durations and cell densities enhanced TNAP expression by hDPSCs. Arresting the hDPSC cell cycle also increased TNAP expression. These data confirm that TNAP is co-expressed by hDPSCs together with other BMSC markers and show that cell density affects TNAP expression levels. We conclude that TNAP is a potentially useful marker for hDPSC selection especially for uses in mineralised tissue regenerative therapies.


Assuntos
Fosfatase Alcalina/análise , Polpa Dentária/citologia , Células Estromais/citologia , 5'-Nucleotidase/análise , 5'-Nucleotidase/metabolismo , Adolescente , Adulto , Fosfatase Alcalina/metabolismo , Contagem de Células , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Proliferação de Células , Polpa Dentária/metabolismo , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Células Estromais/metabolismo , Antígenos Thy-1/análise , Antígenos Thy-1/metabolismo , Adulto Jovem
16.
Analyst ; 140(21): 7347-54, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26374253

RESUMO

There is an unmet need for the non-invasive characterisation of stem cells to facilitate the translation of cell-based therapies. Raman spectroscopy has proven utility in stem cell characterisation but as yet no method has been reported capable of taking repeated Raman measurements of living cells aseptically over time. The aim of this study was to determine if Raman spectroscopy could be used to monitor changes in a well characterised cell population (human dental pulp stromal cells (DPSCs)) by taking repeated Raman measurements from the same cell populations in osteoinductive culture over time and under aseptic conditions. DPSCs were isolated from extracted premolar teeth from 3 consenting donors. Following in vitro expansion, DPSCs were maintained for 28 days in osteo-inductive medium. Raman spectra were acquired from the cells at days 0, 3, 7, 10, 14 and 28. Principal component analysis (PCA) was carried out to assess if there was any temporal spectral variation. At day 28, osteoinduction was confirmed using alizarin red staining and qRT-PCR for alkaline phosphatase and osteocalcin. Alizarin red staining was positive in all samples at day 28 and significant increases in alkaline phosphatase (p < 0.001) and osteocalcin (p < 0.05) gene expression were also observed compared with day 0. PCA of the Raman data demonstrated trends in PC1 from days 0-10, influenced by protein associated features and PC2 from days 10-28, influenced by DNA/RNA associated features. We conclude that spectroscopy can be used to monitor changes in Raman signature with time associated with the osteoinduction of DPSCs using repeated measurements via an aseptic methodology.


Assuntos
Polpa Dentária/citologia , Dente Molar/patologia , Análise Espectral Raman/métodos , Células Estromais/citologia , Adulto , Fosfatase Alcalina/metabolismo , Antraquinonas/química , Diferenciação Celular , Células Cultivadas , Criança , DNA/química , Matriz Extracelular/metabolismo , Feminino , Citometria de Fluxo , Humanos , Masculino , Osteocalcina/metabolismo , Osteogênese , Fenótipo , Análise de Componente Principal , RNA/química , Espectrofotometria , Engenharia Tecidual/métodos , Adulto Jovem
17.
Cell Tissue Res ; 358(1): 123-33, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24916612

RESUMO

Tooth loss often results in alveolar bone resorption because of lack of mechanical stimulation. Thus, the mechanism of mechanical loading on stem cell osteogenesis is crucial for alveolar bone regeneration. We have investigated the effect of mechanical loading on osteogenesis in human dental pulp stromal cells (hDPSCs) in a novel in vitro model. Briefly, 1 × 10(7) hDPSCs were seeded into 1 ml 3% agarose gel in a 48-well-plate. A loading tube was then placed in the middle of the gel to mimic tooth-chewing movement (1 Hz, 3 × 30 min per day, n = 3). A non-loading group was used as a control. At various time points, the distribution of live/dead cells within the gel was confirmed by fluorescence markers and confocal microscopy. The correlation and interaction between the factors (e.g. force, time, depth and distance) were statistically analysed. The samples were processed for histology and immunohistochemistry. After 1-3 weeks of culture in the in-house-designed in vitro bioreactor, fluorescence imaging confirmed that additional mechanical loading increased the viable cell numbers over time as compared with the control. Cells of various phenotypes formed different patterns away from the reaction tube. The cells in the middle part of the gel showed enhanced alkaline phosphatase staining at week 1 but reduced staining at weeks 2 and 3. Additional loading enhanced Sirius Red and type I collagen staining compared with the control. We have thus successfully developed a novel in-house-designed in vitro bioreactor mimicking the biting force to enhance hDPSC osteogenesis in an agarose scaffold and to promote bone formation and/or prevent bone resorption.


Assuntos
Polpa Dentária/metabolismo , Osteogênese/fisiologia , Reatores Biológicos , Células Cultivadas , Polpa Dentária/citologia , Feminino , Humanos , Masculino , Células Estromais/citologia , Células Estromais/metabolismo , Alicerces Teciduais/química , Suporte de Carga/fisiologia
18.
Cell Tissue Res ; 356(1): 97-107, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24408074

RESUMO

Translational research in bone tissue engineering is essential for "bench to bedside" patient benefit. However, the ideal combination of stem cells and biomaterial scaffolds for bone repair/regeneration is still unclear. The aim of this study is to investigate the osteogenic capacity of a combination of poly(DL-lactic acid) (PDLLA) porous foams containing 5 wt% and 40 wt% of Bioglass particles with human adipose-derived stem cells (ADSCs) in vitro and in vivo. Live/dead fluorescent markers, confocal microscopy and scanning electron microscopy showed that PDLLA/Bioglass porous scaffolds supported ADSC attachment, growth and osteogenic differentiation, as confirmed by enhanced alkaline phosphatase (ALP) activity. Higher Bioglass content of the PDLLA foams increased ALP activity compared with the PDLLA only group. Extracellular matrix deposition after 8 weeks in the in vitro cultures was evident by Alcian blue/Sirius red staining. In vivo bone formation was assessed by using scaffold/ADSC constructs in diffusion chambers transplanted intraperitoneally into nude mice and recovered after 8 weeks. Histological and immunohistochemical assays indicated significant new bone formation in the 40 wt% and 5 wt% Bioglass constructs compared with the PDLLA only group. Thus, the combination of a well-developed biodegradable bioactive porous PDLLA/Bioglass composite scaffold with a high-potential stem cell source (human ADSCs) could be a promising approach for bone regeneration in a clinical setting.


Assuntos
Tecido Adiposo/citologia , Osso e Ossos/fisiologia , Cerâmica/farmacologia , Ácido Láctico/farmacologia , Polímeros/farmacologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno/biossíntese , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Poliésteres , Transplante de Células-Tronco , Células-Tronco/efeitos dos fármacos , Células-Tronco/enzimologia , Células-Tronco/ultraestrutura
19.
Cureus ; 16(5): e61321, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38947683

RESUMO

Carcinoid syndrome is a rare condition resulting from neuroendocrine tumors (NETs) that secrete vasoactive substances like serotonin. This report describes the case of a 61-year-old man with a history of chronic obstructive pulmonary disease (COPD) and hypertension who presented with new-onset angioedema, loss of consciousness, and a fall. He had been treated for COPD exacerbations during ER visits without improvement and was unaware of a prior mesenteric carcinoid tumor diagnosis from 2012. The next emergency evaluation revealed significant airway and facial edema necessitating intubation. Imaging and biopsy identified a well-differentiated grade 1 NET with extensive liver metastases. Laboratory tests showed elevated levels of serum serotonin, chromogranin A, and 24-hour urine 5-hydroxyindoleacetic acid (5-HIAA). Post-discharge, a PET scan confirmed metastatic lesions primarily in the liver and small bowel, with an unresectable mesenteric mass. The patient was treated with lanreotide and became symptom-free. This case underscores the need to consider carcinoid syndrome in patients with COPD presenting with unexplained respiratory symptoms, as timely diagnosis and treatment can significantly enhance patient outcomes.

20.
Adv Healthc Mater ; : e2303836, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507269

RESUMO

Chronic diabetic wounds pose significant challenges due to uncontrolled bacterial infections, prolonged inflammation, and impaired angiogenesis. The rapid advancement of photo-responsive antibacterial therapy showed promise in addressing these complex issues, particularly utilizing 2D heterojunction materials, which offer unique properties. Herein, we designed an in situ sprayed Bi/BiOCl 0D/2D heterojunction composite fibrin gel with the characteristics of rapid formation and effective near-infrared activation for the treatment of non-healing diabetes-infected wounds. The sprayed composite gel can provide protective shielding for skin tissues and promote endothelial cell proliferation, vascularization, and angiogenesis. The Bi/BiOCl 0D/2D heterojunction, with its localized surface plasmon resonance (LSPR), can overcome the wide bandgap limitation of BiOCl, enhancing the generation of local heat and reactive oxygen species under near-infrared irradiation. This facilitated bacterial elimination and reduced inflammation, supporting the accelerated healing of diabetes-infected wounds. Our study underscores the potential of LSPR-enhanced heterojunctions as advanced wound therapies for chronic diabetic wounds. This article is protected by copyright. All rights reserved.

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