Assessment of Mitochondrial Function and Developmental Potential of Mouse Oocytes after Mitoquinone Supplementation during Vitrification.

Vitrification negatively affects the mitochondrial membrane potential (ΔΨm) in oocytes while also leading to increased reactive oxygen species (ROS), ATP depletion and induction of apoptosis in oocytes. Mitoquinone (MitoQ) is an antioxidant that protects mitochondrial membrane integrity from ROS. This study examined the effect of adding MitoQ to vitrification medium on mitochondrial function and embryo development in vitrified oocytes. Metaphase II (MII) stage oocytes were collected from NMRI mouse ovaries and preincubated for 20 min in a medium containing 0.02 µM of MitoQ. Next, oocytes were vitrified in medium supplemented with 0.02µM of MitoQ (treatment group). The control group was processed in the same way but without exposure to MitoQ. After warming, oocyte survival rate, ΔΨm, cytoplasmic ROS and glutathione (GSH) levels and gene expression levels (Bcl2, BAX, and caspase3) were measured. In addition, the vitrified oocytes were fertilized in-vitro to assess developmental competence. The results showed that MitoQ improved survival and ΔΨm in treated vitrified oocytes. Treated oocytes showed lower ROS levels and higher GSH levels than did the control group. Furthermore, mRNA expression of the Bax/ Bcl2 ratio and caspase3 were significantly lower in treated oocytes. These findings indicate that medium supplementation with 0.02 µM of MitoQ during vitrification can improve oocyte survival and developmental competency in mouse oocytes.

Bones Morphogenic Protein-4 and retinoic acid combined treatment comparative analysis for in vitro differentiation potential of murine mesenchymal stem cells derived from bone marrow and adipose tissue into germ cells.

Nowadays, infertility is no longer considered as an unsolvable disorder due to progresses in germ cells derived from stem lineage with diverse origins. Technical and ethical challenges push researchers to investigate various tissue sources to approach more efficient gametes. The purpose of the current study is to investigate the efficacy of a combined medium, retinoic acid (RA) together with Bone Morphogenic Protein-4 (BMP4), on differentiation of Bone Marrow Mesenchymal Stem Cells (BMMSCs) and adipose-derived mesenchymal stem cells (ADMSCs) into germ cells. Murine MSCs were obtained from both Bone Marrow (BM) and Adipose Tissue (AT) samples and were analyzed for surface markers to get further verification of their nature. BMMSCs and ADMSCs were induced into osteogenic and adipogenic lineage cells respectively, to examine their multipotency. They were finally differentiated into germ cells using media enriched with BMP4 for 4 days followed by addition of RA for 7 days (11 days in total). Analyzing of differentiation potential of BMMSCs- and ADMSCs were performed via Immunofluorescence, Flowcytometry and Real time-PCR techniques for germ cell-specific markers (Mvh, Dazl, Stra8 and Scp3). Mesenchymal surface markers (CD90 and CD44) were expressed on both BMMSCs and ADMSCs, while endothelial and hematopoietic cell markers (CD31 and CD45) had no expression. Finally, all germ-specific markers were expressed in both BM and AT. Although germ cells differentiated from ADMSCs showed faster growth and proliferation as well as easy collection, they significantly expressed germ-specific markers lower than BMMSCs. This suggests stronger differentiation potential of murine BMMSCs than ADMSCs.