Melatonin effect during different maturation stages of oocyte and subsequent embryo development in mice

Background: it is important to protect oocytes and embryos from oxidative stress in the culture medium. Melatonin has been shown to be a direct free radical scavenger

Objective: Effect of melatonin during in vitro oocyte maturation, fertilization and embryo development of mouse oocytes was evaluated

Materials and Methods: oocytes from supper-ovulated mouse were divided to two groups: cumulus oocyte complexes [COCs, group I] and denuded COC [d-COCs, group II]. The oocytes were cultured in maturation medium with different doses of melatonin [1×10[1]-10[5] nM] The cumulus expansion and nuclear status were evaluated after 24 h of in-vitro maturation. The oocytes were used for in-vitro fertilization. The fertilized oocytes were cultured in medium supplemented with different doses of melatonin

Results: the expansion [86.79%] and maturation [80.55%] rate of COCs increased in supplemented medium with 10 nM of melatonin vs. control group [73.33%], p=0.006 and p=0.026 respectively], but oocytes without cumulus cells indicated higher maturation rate at higher melatonin doses [10 and 100 ?M, 84.34% and 79.5% respectively[ vs. 69.33% in control group [p=0.002]. Fertilization rate was higher in treated medium with 1 [micro]M of melatonin [93.75%, p=0.007]

The rate of cleavage and blastocyst formation was promoted in medium supplemented with 10 and 100 nM of melatonin [92.37% and 89.36% vs. 81.25% in control group, p=0.002] We observed a dose dependent response to melatonin treatment in this experiment

Conclusion: exogenous melatonin can promote cumulus cell expansion, in vitro oocyte maturation, and embryo development. However we investigated a dose-dependent response in different stages of maturation and development. It may reflect sensitive rate of oocytes and embryos to culture conditions

Neuroprotective effect of total and sequential extract of Scrophularia striata boiss. in rat cerebellar granule neurons following glutamate-induced neurotoxicity: an in-vitro study

Neuroprotective effect of the extract from aerial parts of Scrophularia striata Boiss [Scrophulariaceae] was investigated against glutamate-induced neurotoxicity on cultured rat pups Cerebellar Granule Neurons [CGNs]. CGNs from 8 days old Sprague-Dawley rat were prepared and cultured. The experiments were performed after 8 days in culture. The plant was collected from the northeastern part [Ruin region] of Iran and air-dried at room temperature. The total extract was prepared with maceration of prepared powder in ethanol 80% for three times. Sequential extracts were obtained using dried and powdered aerial parts with increasingly polar solvents: petroleum ether, chloroform, ethyl acetate and methanol 80% solution. Cultured cells were exposed to 125 micro M of glutamate for 12 h following a 24 h of incubation with test fractions at concentration of 10 mcg/mL. Morphological assay was performed using invert light microscope after fixation and staining with haematoxylin. Neuronal viability was measured using MTT assay. Statistical analysis was done using SPSS software. One way analysis of variance [ANOVA] was performed by Tukey post-hoc test. Values were considered statistically significant when p-value < = 0.05. Results of this study showed a significant neuroprotective activity of high polarity methanolic fraction of aerial parts of Scrophularia striata against glutamate-induced neurotoxicity in a dosedependent manner. Treatment with 10 mcg/mL of the fractions showed the best result

effect of melatonin on the developmental potential and implantation rate of mouse embryos

Melatonin is a scavenger agent that has been used to promote in vitro embryo development. This study was designed to show the effects of melatonin on the quality and quantity rate of preimplantation mouse embryo development and pregnancy. In this experimental study, super ovulated, mated mice were killed by cervical dislocation to collect two-cell zygotes from the oviduct of pregnant 1 day NMRI mice. Zygotes were cultured to the hatching blastocyst stage and the numbers of embryos at different stages were recorded under an inverted microscope. The cleavage rates of two-cell zygotes were assayed until the blastocyst and hatching blastocyst stage in drops of T6 medium that contained either melatonin [1, 10, and 100×10[6], 10 and 100×10[9] M] or no melatonin. The cell numbers of blastocysts were determined by differential staining, implantation outcomes were studied, and development and pregnancy rate were compared by the Chi-square [development] and Fisher's exact [pregnancy rate] tests. The addition of 10 and 100 nM melatonin to the embryo culture media promoted the development of the two-cell stage embryos to blastocyst and hatching blastocysts [p<0.01] and caused a significant increase in total cell number [TCN], trophoectoderm [TE], and inner cell mass [ICM] of the blastocysts [p<0.01]. A difference was observed in the percentage of transferred embryos that were successfully implanted between the control and treatment groups [p<0.05]. The data indicate that 10 and 100 nM of melatonin positively impact mouse embryo cleavage rates, blastocyst TCN, and their implantation. Therefore, melatonin at low concentrations promotes an embryonic culture system in mice

[Comparison of the differentiation potential of human mesenchymal stem cells and several animal species]

Considering the increasing use of mesenchymal stem cells isolated from various sources in the clinic, the basic studies needed to evaluate proliferation, differentiation and other biological characteristics of them done. In the present study, efficiency and power differentiation in five different categories mesenchymal stem cells are compared with each other. Bone marrow mesenchymal stem cells from rabbits, rats, C57 mice, chicken and mesenchymal stem cells derived from human knee synovium tissue were cultured with a density of 5000 cells/ cm2 in 12-chamber dishes. After the cells reached the appropriate level of growth, specific differentiation inducers were added. 21 days, differentiation of all stem cells to adipocyte, osteocyte and chondrocyte were evaluated and compared using specific staining methods. Our results indicated that all five mesenchymal stem cells were able to differentiate into osteocyte, adipocyte and chondrocyte. Moreover, the highest potentials for differentiation to adipocyte and osteocyte and chondrocyte were seen in mesenchymal stem cells derived from chicken bone marrow and human synovium, respectively. In this study, differences in the differentiation potential of mesenchymal stem cells isolated from different tissues and species were observed that could be caused by small differences in their environment in vivo. Understanding these differences can lead to more effective use of these cells in the clinic