Functional role of Forskolin and PD166285 in the development of denuded mouse oocytes.

OBJECTIVE: cAMP and mature promoting factor (MPF) play critical roles during the maturation of mammalian oocytes. The aim of this study was to produce the offspring from denuded oocytes (DOs) in mice by regulating cAMP and MPF. METHODS: In this study, we used DOs at the germinal vesicle (GV) stage in mice and regulated levels of cAMP and MPF in DOs by adding Forskolin and PD166285 during in vitro maturation without follicle stimulating hormone and luteinizing hormone, respectively. RESULTS: Combined use of 50 µM Forskolin for 3 h and 2.5 µM PD166285 for additional 21 h enhanced the developmental competence of DOs, maturation rate of DOs was 76.71%± 4.11%, blastocyst rate was 18.33%±4.44% after parthenogenetic activation (PA). The DOs could successfully be fertilized with sperm in vitro, cleavage rate was 17.02%±5.82% and blastocyst rate was 5.65%±3.10%. Besides, 2-cell in vitro fertilization embryos from DOs produced 4 normal live offspring (4/34). CONCLUSION: The results confirmed that the combination of Forskolin and PD166285 can induce DOs to complete meiosis process and produce normal offspring.

All-trans retinoic acid improves goat oocyte nuclear maturation and reduces apoptotic cumulus cells during in vitro maturation.

All-trans retinoic acid (t-RA) is a natural component and representative physiologically active metabolite of vitamin A, having multiple physiologic functions. The objective of this study was to evaluate the effect of t-RA on goat oocyte maturation and cumulus cell apoptosis during in vitro maturation (IVM). Immature goat cumulus-oocyte complexes (COCs) were matured in vitro in the absence or presence of t-RA at concentrations of 10 nmol/L, 100 nmol/L and 1000 nmol/L. Oocyte maturation and embryo development were assessed by polar body formation and parthenogenetic activation, respectively. Oocyte survival was checked by Trypan blue staining. Apoptosis of cumulus cells was analyzed by terminal deoxynucleotidyl transferase nick end labeling staining and quantitative real-time PCR. In comparison with the control group, 100 nmol/L and 10 nmol/L t-RA significantly improved goat nuclear oocyte maturation and survival (P < 0.05). Addition of 1000 nmol/L t-RA improved nuclear maturation (P < 0.05), but had no effect on survival of goat oocytes. t-RA had no positive effect on goat parthenogenetic embryonic cleavage, blastocyst formation or total cell numbers. However, t-RA inhibits the apoptosis of cumulus cells (P < 0.01). t-RA treatment up-regulated the expression of B-cell lymphoma 2 (BCL-2), catalase (CAT) (P < 0.05) and down-regulated the expression of Caspase-8 (P < 0.05). In conclusion, t-RA has positive effects on goat oocyte nuclear maturation and reduces apoptotic cumulus cells during IVM.

Effects of vitamin C on characteristics retaining of in vitro-cultured mouse adipose-derived stem cells.

Adipose-derived stem cells (ADSCs), a subset of mesenchymal stem cells, have promising potential for regenerative medicine applications. However, the efficient culture of mouse adipose-derived stem cells (mADSCs) is complicated or impracticable and many properties of mADSCs are still unknown. Here, we report that vitamin C (Vc) is available for the long-term culture of mADSCs in vitro. Compared with that cultured without Vc, mADSCs growing in Vc-added media proliferate faster. The occurrence of replicative senescence and transformation of Vc-treated mADSCs is also postponed. Vc also enhanced the secretory activity of collagen and adipogenic differentiation ability of mADSCs. Moreover, the expression of CD44, Sca-1, and CD105 is higher in Vc-treated mADSCs than nontreated ones. We also found that genes related to proliferation, secretion, and pluripotency are all promoted in Vc-treated mADSCs. However, the adipogenesis ability and expression of CD44, Sca-1, and CD105 decreased when passage increased from very low passages, in parallel to the downregulation of closed-related gene expression. Our results indicate that Vc is essential for the maintenance of original properties of mADSCs in vitro; additional insights into the function of Vc on mADSCs are provided. Furthermore, as the passage increased in six passages, the characteristics of mADSCs with Vc addition were also revealed.