5-ethynyl-2--deoxyuridine and thiazolyl-blue

To investigate particulate matter (PM2.5)-induced damage to human corneal epithelial cells (HCECs) and to determine the underlying mechanisms.. HCECs were exposed to PM2.5 at a series of concentrations for various periods. Cell viability was measured by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell proliferation was evaluated via 5-ethynyl-2'-deoxyuridine (EdU) analysis, while autophagy was determined by immunofluorescence and Western blot.. PM2.5-induced cell damage of HCECs occurred in a time- and dose-dependent manner. Decreased cell viability and proliferation as well as increased apoptosis were observed in HCECs after PM2.5 exposure for 24 h. Autophagy in HCECs was slightly inhibited in the early stage (before 4 h) of exposure but significantly activated in the late stage (after 24 h), as evidenced by a decrease in the former and increase in the latter of the expression of the autophagy-associated markers LC3B, ATG5, and BECN1. Interestingly, rapamycin, an autophagy activator, attenuated early-stage but aggravated late-stage PM2.5-induced cell damage, suggesting that the role of autophagy in HCECs may change over time during PM2.5 exposure. In addition, in the early stage, the expression of LC3B and ATG5 increased in cells co-treated with rapamycin and PM2.5 compared to rapamycin-only or PM2.5-only treated cells, suggesting that autophagy may benefit cell viability after PM2.5 exposure.. The results indicate the potential role of autophagy in the treatment of PM2.5-induced ocular corneal diseases and provide direct evidence for the cytotoxicity, possibly involving an autophagic process, of PM2.5 in HCECs.

Topics: Air Pollutants; Apoptosis; Autophagy; Cell Line; Cell Proliferation; Cell Survival; Deoxyuridine; Epithelial Cells; Humans; Particulate Matter; Tetrazolium Salts; Thiazoles; Toxicity Tests

Tissue regeneration using adult stem cells (ASCs) has significant potential as a novel treatment for many degenerative diseases. Previous studies have established that age negatively affects the proliferation status and differentiation potential of ASCs, suggesting a possible limitation in their potential therapeutic use. Therefore, we hypothesized that apple extract might exert beneficial effects on ASCs. The specific objectives were to investigate the proliferative effect of apple ethanol extract on human adipose tissue-derived mesenchymal stem cells (ADSCs) and human cord blood-derived mesenchymal stem cells (CB-MSCs), and identify the possible molecular mechanisms. Apple extract promoted proliferation of ADSCs and CB-MSCs as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assays. In addition, phosphorylation of p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase (p70S6K), S6 ribosomal protein (S6RP), eukaryotic initiation factor (eIF) 4B and eIF4E was induced stepwise in ADSCs. Furthermore, apple extract significantly induced the production of vascular endothelial growth factor and interleukin-6 in both ADSCs and CB-MSCs. Similarly, apple extract-induced phosphorylation of the mTOR/p70S6K/S6RP/eIF4B/eIF4E pathway was blocked by pretreatment with PD98059, a specific ERK inhibitor. These results indicate that apple extract-induced proliferation of ADSCs under serum-free conditions is mediated by ERK-dependent cytokine production. Moreover, the beneficial effect of apple extract on proliferation of ASCs may overcome the limitation in therapeutic use of stem cells in tissue regeneration and maintenance of stem cell homeostasis.

Topics: Adipose Tissue; Adult; Adult Stem Cells; Cell Differentiation; Cell Proliferation; Deoxyuridine; Eukaryotic Initiation Factors; Fetal Blood; Humans; Interleukin-6; Malus; Mesenchymal Stem Cells; Mitogen-Activated Protein Kinase 3; Phosphorylation; Plant Extracts; Regeneration; Ribosomal Protein S6 Kinases, 70-kDa; Tetrazolium Salts; Thiazoles; TOR Serine-Threonine Kinases; Vascular Endothelial Growth Factor A

It has been reported that integrin-α5 (ITGA5) activity is related to cell proliferation, differentiation, migration, and organ development. However, the involvement of ITGA5 in the biological functions of human dental pulp stem cells (hDPSCs) has not been explored. The aim of this study was to investigate the role of ITGA5 in the proliferation and odontogenic differentiation of hDPSCs.. We knocked down ITGA5 in hDPSCs using lentivirus-mediated ITGA5 short hairpin RNA (shRNA). Changes in the proliferation in hDPSCs infected with lentiviruses expressing ITGA5-specific shRNA or negative control shRNA were examined using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 5-ethynyl-2'-deoxyuridine labeling. Both ITGA5 knockdown cells and shMock cells were cultured in mineralization medium for 3 weeks, and the differentiation of cells was detected with alizarin red S staining. The expression of odontogenic differentiation-related molecular markers was assessed using real-time polymerase chain reaction and Western blot assays.. The knockdown of ITGA5 decreased the proliferation capacity of hDPSCs. ITGA5 shRNA promoted odontogenic differentiation of hDPSCs with the enhanced formation of mineralized nodules. It also up-regulated the messenger RNA expression of multiple markers of odontogenesis and the expression of dentin sialophosphoprotein protein.. These findings suggest that ITGA5 plays an important role in maintaining hDPSCs in a proliferative state. The inhibition of ITGA5 signaling promotes the odontogenic differentiation of hDPSCs.

Topics: Anthraquinones; Calcification, Physiologic; Cell Differentiation; Cell Proliferation; Cells, Cultured; Coloring Agents; Dental Pulp; Deoxyuridine; Extracellular Matrix Proteins; Gene Knockdown Techniques; Genetic Vectors; Humans; Integrin alpha5; Lentivirus; Odontogenesis; Phosphoproteins; Real-Time Polymerase Chain Reaction; RNA, Small Interfering; Sialoglycoproteins; Stem Cells; Tetrazolium Salts; Thiazoles

This study was conducted to investigate the proliferative effect of vegetable soy peptides on adult stem cells (ASCs) in the absence of serum and their possible mechanisms of action. The proliferation of human adipose tissue-derived mesenchymal stem cells (ADSCs) and cord blood-derived mesenchymal stem cells (CB-MSCs) treated with soy peptides was found to increase significantly upon 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assay. In addition, soy peptides led to stepwise phosphorylation of the p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase, S6 ribosomal protein (S6RP) and eukaryotic initiation factor 4E (eIF4E) in ADSCs. Furthermore, quantitative analysis of the cytokines revealed that the production of transforming growth factor-beta1 (TGF-β1), vascular endothelial growth factor and interleukin-6 increased significantly in response to treatment with soy peptides in both ADSCs and CB-MSCs. Similarly, soy peptide-induced phosphorylation of the ERK/mTOR/S6RP/eIF4E pathway was blocked in response to pretreatment with PD98059, a specific ERK inhibitor. Moreover, inhibition of TGF-β1 through PD98059 pretreatment and a consecutive decrease in ADSC proliferation revealed that TGF-β1 induces the phosphorylation of mTOR/S6RP/eIF4E. Collectively, the results of this study indicate that ERK-dependent production of TGF-β1 plays a crucial role in the soy peptide-induced proliferation of ADSCs under serum-free conditions.

Topics: Cell Line; Cell Proliferation; Deoxyuridine; Eukaryotic Initiation Factor-4E; Gene Expression Regulation; Humans; Interleukin-6; MAP Kinase Signaling System; Mesenchymal Stem Cells; Mitogen-Activated Protein Kinase 3; Phosphorylation; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Soybean Proteins; Tetrazolium Salts; Thiazoles; TOR Serine-Threonine Kinases; Transforming Growth Factor beta1; Vascular Endothelial Growth Factor A