Periodontal Ligament Fibroblast Cell Viability Following Treatment with Different Concentrations of Green Tea, Aloe Vera and a Mixture of their Extracts.

Objectives: Various studies have identified green tea and Aloe vera as a suitable medium for avulsed teeth. The aim of this study was to evaluate and compare the viability of periodontal ligament (PDL) fibroblasts following treatment with the extracts of these two plants and their mixture. Materials and Methods: Human PDL fibroblasts were purchased and treated with different concentrations of Aloe vera, green tea, and a combination of these two extracts. Hank's balanced salt solution and culture medium were employed as positive and negative controls, respectively. Viability was assessed using the MTT assay. Two-way ANOVA and post-hoc tests were used for statistical analysis (P<0.05). Results: There was a significant difference in PDL fibroblast viability between different concentrations of the extracts. Higher concentrations of green tea and the combination of the two extracts significantly increased cell viability. Higher concentrations of Aloe vera had the least positive effect on maintaining the viability of these cells. Conclusion: If confirmed by further studies, the combination of Aloe vera and green tea extracts might be considered as a suitable media for different purposes like storing avulsed teeth.

Long-Term Inhibition of Notch in A-375 Melanoma Cells Enhances Tumor Growth Through the Enhancement of AXIN1, CSNK2A3, and CEBPA2 as Intermediate Genes in Wnt and Notch Pathways.

Notch suppression by gamma-secretase inhibitors is a valid approach against melanoma. However, most of studies have evaluated the short-term effect of DAPT on tumor cells or even cancer stem cells. In the present study, we surveyed the short-term and long-term effects of DAPT on the stem cell properties of A375 and NA8 as melanoma cell lines. The effects of DAPT were tested both in vitro and in vivo using xenograft models. In A375 with B-raf mutation, DAPT decreased the level of NOTCH1, NOTH2, and HES1 as downstream genes of the Notch pathway. This was accompanied by enhanced apoptosis after 24 h treatment, arrest in the G2-M phase, and impaired ability of colony and melanosphere formation at the short term. Moreover, tumor growth also reduced during 13 days of treatment. However, long-term treatment of DAPT promoted tumor growth in the xenograft model and enhanced the number and size of colonies and spheroids in vitro. The gene expression studies confirmed the up-regulation of Wnt and Notch downstream genes as well as AXIN1, CSNK2A3, and CEBPA2 following the removal of Notch inhibitor in vitro and in the xenograft model. Moreover, the Gompertz-based mathematical model determined a new drug resistance term in the present study. Our data supported that the long-term and not short-term inhibition of Notch by DAPT may enhance tumor growth and motility through up-regulation of AXIN1, CSNK2A3, and CEBPA2 genes in B-raf mutated A375 cells.

Decellularized muscle-derived hydrogels support in vitro cardiac microtissue fabrication.

Cardiovascular research has considerably benefited from in vitro models of cardiac tissue. Two important elements of these constructs, cardiac cells and the extracellular matrix (ECM), play essential roles that mimic the structural and functional aspects of myocardium. Here, we compared decellularized ECM from cardiac muscle (D-CM), skeletal muscle (D-SM), aorta (D-Ao), liver (D-Liv), small intestine submucosa (D-SIS), and human umbilical cord (D-hUC) in terms of their biocompatibility and potential for differentiation of human embryonic stem cell-derived cardiac progenitor cells (hESC-derived CPCs) to cardiovascular lineage cells. The decellularization procedure successfully removed resident cells of the tissues but preserved ECM components such as laminin and fibronectin, which was identified by histological studies of decellularized tissue (D-tissues) and immunostaining. Encapsulation of hESC-derived CPCs and human umbilical vein endothelial cells within hydrogels that were obtained from all decellularized tissues did not induce cytotoxicity after 10 days of culture. Upregulation of cardiac specific genes, cTNT and αMHC, as well as the presence of cTNT+ cardiomyocytes were also observed in CPCs cultured on D-CM, D-SM, D-Liv, and D-SIS, which showed their support for cardiogenic differentiation. However, D-CM provided substantially higher expression of cardiac markers compared to the other D-tissues. The endothelial and smooth muscle specific genes, CD31 and PDGFRα, were upregulated in cells cultured on D-Ao and D-hUC, which reflected their support for vascular lineage cell differentiation. In conclusion, it might be imperative to use decellularized tissue of muscle origins in combination with naturally derived vascular tissues to generate in vitro vascularized human cardiac microtissues.

Generation of Transplantable Three-Dimensional Hepatic-Patch to Improve the Functionality of Hepatic Cells In Vitro and In Vivo.

Cell therapy and tissue engineering (TE) are considered alternative therapeutic approaches to organ transplantation. Since cell therapy approaches achieved little success for liver failure treatment, liver TE is considered a more promising alternative. In this study, we produced a liver tissue equivalent (called "liver-derived extracellular matrix scaffold [LEMS]-Patch") by co-culture of human bone marrow stromal cells, human umbilical vein endothelial cells, and a hepatoma cell line, Huh7, within an artificial three-dimensional liver-extracellular matrix scaffold. The results showed significant increase in the liver-specific gene expression and hepatic functions, in terms of albumin (ALB) and fibrinogen secretion, urea production, and cytochrome inducibility in the LEMS-Patch compared to controls. In addition, transplanted LEMS-Patch was successfully incorporated into the recipient liver of acute liver failure mice and produced human ALB. Consequently, our data demonstrated that the generated LEMS-Patch could be used as a good platform for functional improvement of hepatic cells in vitro and in vivo.