ABSTRACT
BACKGROUND: Gamete cryopreservation is an inseparable part of assisted reproductive technology, and vitrification is an effective approach to the cryopreservation of oocytes. The aim of this study was to investigate vitrification effects on the expression levels of mitochondrial transcription factor A (Tfam) and mitochondrial-encoded cytochrome c oxidase subunit 1 (Cox1) in mouse metaphase II oocytes. METHODS: Oocytes were selected by simple random sampling and distributed amongst five experimental groups (control [n=126], docetaxel [n=132], docetaxel+cryoprotectant agent [CPA] [n=134], docetaxel+vitrification [n=132], and vitrification [n=123]). After the warming process, the oocytes were fertilized and cultured into a 2-cell stage. Then, the effects of vitrification on the expression of the Tfam and Cox1 genes were determined via real-time reverse transcriptase polymerase chain reaction. Each group was compared with the control group. The data were analyzed with ANOVA using GraphPad and SPSS, version 21. RESULTS: A significant decrease was observed in the fertilization rate of each group in comparison with the control group (P=0.001). The rate of 2-cell formation after in vitro fertilization was significantly lower in both vitrification groups (docetaxel+vitrification and vitrification) than in the non-vitrification groups (fresh control and docetaxel) and control group (P=0.001 and P=0.004). The expression level of Cox1 was significantly higher in the vitrification group than in the control group (P=0.01), while it was lower in the docetaxel group than that in the control group (P=0.04). The expression level of the Tfam gene was significantly high in the vitrification group (vitrification+docetaxel) and the non-vitrified group (docetaxel+CPA) in comparison with the control group (P=0.01). CONCLUSION: This study indicated that the vitrification of mouse MII oocytes increased the expression of the Tfam and Cox1 genes.
ABSTRACT
The function of fibroblast cells in wounded areas results in reconstruction of the extra cellular matrix and consequently resolution of granulation tissue. It is suggested that the use of platelet-rich plasma can accelerate the healing process in nonhealing or slow-healing wounds. In this study, a simple and novel method has been used to fabricate an electrospun three-layered scaffold containing plasma rich in growth factor with the aim of increasing the proliferation and migration of fibroblast cells in vitro. First, plasma rich in growth factor was derived from platelet rich plasma, and then a three-layered scaffold was fabricated using PLLA nanofibers as the outer layers and plasma rich in growth factor-containing gelatin fibers as the internal layer. The growth morphology of cells seeded on this scaffold was compared to those seeded on one layered PLLA scaffold. The study of the cell growth rate on different substrates and the migration of cells in response to the drug release of multilayered scaffold was investigated by the cell quantification assay and a modified under agarose assay. Scanning electron microscopy and fluorescence images showed that cells seeded on multilayered scaffold were completely oriented 72 hours after seeding compared to those seeded on PLLA scaffold. The cell quantification assay also indicated significant increase in proliferation rate of cells seeded on three-layered scaffold compared to those seeded on PLLA scaffold and finally, monitoring cell migration proved that cells migrate significantly toward the three-layered scaffold up to 48 to 72 hours and afterwards start to show a diminished migration rate toward this scaffold.
