[Progesterone induction keeps a balanced mitochondrial activity and a low ROS productivity in human sperm].

OBJECTIVE: To observe the relative activity of sperm mitochondria and the proportion of ROS-positive sperm before and after capacitation and progesterone (Pg)-induced hyperactivation, and investigate the functional characteristics of sperm mitochondria. METHODS: We collected 20 samples of normal human spermatozoa that met the criteria of WHO Laboratory Manual for the Examination and Processing of Human Semen (5th ed) and cultured them with the swim-up method in a CO2 incubator at 37 degrees C for 1 hour. We divided the sperm into a pre-capacitation and a capacitated group, and further incubated the capacitated sperm in an upright tube with (Pg-induced group) or without (control group) slow-releasing Pg at 37 degrees C for another hour. Then we determined the relative activity of mitochondria and the percentage of ROS-positive cells in the sperm samples using JC-1 and DCF staining. RESULTS: The relative activities of mitochondria were significantly increased in the capacitated, control and Pg-induced groups (6.23, 14.36 and 12.33) as compared with the pre-capacitation group (1.42) (P < 0.05), while the percentages of balanced mitochondria (mitochondria with equal amount of high and low electric potentials) remarkably reduced (4.27%, 5.03% and 8.57% vs 21.64%, P < 0.05). The percentages of ROS-positive sperm in the pre-capacitation, capacitated, control and Pg-induced groups were 2.89%, 0.70%, 4.25% and 1.90%, respectively, significantly lower in the capacitated than in the pre-capacitation group (P < 0.01), but dramatically increased in the control group after another hour of swim-up incubation and markedly higher than in the Pg-induced group (P < 0.01). CONCLUSION: Progesterone induction can hyperactive human sperm motility, inhibit the relative activity of mitochondria, keep mitochondria potential at a more balanced level, and reduce the production of ROS, which may help to raise the rate of in vitro fertilization and improve the quality of embryos.

Developmental and hormonal regulation of cumulus expansion and secretion of cumulus expansion-enabling factor (CEEF) in goat follicles.

The objective of this article was to study the developmental and hormonal regulation of cumulus expansion and secretion of cumulus expansion-enabling factor (CEEF) in goat follicles. M-199 medium was conditioned for 24 hr with cumulus-denuded oocytes (DOs), oocytectomized complexes (OOXs), or mural granulosa cells (MGCs) from goat follicles of different sizes. Mouse OOXs and eCG were added to culture drops of the conditioned medium and cumulus expansion was scored at 18 hr of culture to assess CEEF production. While mouse OOXs did not expand, goat OOXs underwent full cumulus expansion when cultured in nonconditioned eCG-supplemented M-199 medium. When cultured in nonconditioned medium containing 10% follicular fluid (FF) from goat medium (2-4 mm) and small (0.8-1.5 mm) follicles, 71-83% mouse OOXs expanded; but expansion rates decreased (P < 0.05) at either lower or higher FF concentrations. FF from large (5-6 mm) follicles did not support mouse OOX expansion at any concentrations. While medium conditioned with DOs from follicles of all the three sizes supported expansion of 80-90% mouse OOXs, medium conditioned with mature DOs had no effect. While cumulus cells from follicles of all the three sizes secreted CEEF in the absence of gonadotropins, MGCs from large follicles became gonadotropin dependent for CEEF production. Both FSH and LH stimulated CEEF production by large follicle MGCs, but FSH had a shorter half-life than LH to expand mouse OOXs. Few meiosis-incompetent goat oocytes from small follicles underwent cumulus expansion when cultured in medium conditioned with goat DOs or cocultured with goat COCs from medium follicles. It is concluded that (1) goat cumulus expansion is independent of the oocyte; (2) the limited CEEF activity in FF from large follicles was due mainly to the inability of MGCs in these follicles to secret the factor in absence or short supply of gonadotropins; (3) the cumulus expansion inability of the meiosis incompetent goat oocytes was due to the inability of their cumulus cells to respond to rather than to produce CEEF.

Reprogrammed peripheral blood mononuclear cells are able to survive longer in irradiated female mice.

Induced multipotent stem (iMS) cells are originated from somatic cells and become multipotent by genetic and/or epigenetic modifications. Previous studies have shown that the fish oocytes extracts (FOE) can induce skin fibroblast cells into iMS cells. In this study, we aim to determine whether FOE can similarly induce mouse peripheral blood mononuclear cells (PBMCs) into the iMS state and if so, whether they can survive longer when they are transplanted into the irradiation female mice. PBMCs of GFP-transgenic male mice were cultured and transiently reprogrammed by FOE. They were deemed reaching the iMS state after detection of expression of stem cell markers. The iMS-like PBMCs were transplanted into female C57BL mice by tail vein injection. The spleen wet weights as well as numbers of colonies of the recipient mice were examined. The results showed the spleen wet weights and numbers of spleen colonies of FOE-induced group were all significantly higher than those of the non-induced group and negative control group. On day 90 after transplantation, FISH analysis detected the presence of Y chromosome in the induced group, but not of the other groups. The current findings demonstrate that FOE-induced PBMCs are able to survive longer in irradiated female mice.

Comparative study among three different methods of bone marrow mesenchymal stem cell transplantation following cerebral infarction in rats.

The objective of this study was to investigate the effects of transplanted bone marrow mesenchymal stem cells (BMSCs) administered via internal jugular vein injection, carotid artery injection, or intraventricular transplantation for the treatment of cerebral infarction, which was modeled in rats. The neurological scores of the treated rats and the distribution of the transplanted cells (GFP-labeled) in the infarction area were evaluated. The cerebral infarction model was produced by inserting a modified Zea-longa suture, which generated middle cerebral artery occlusion (MCAO). The GFP-labeled BMSCs were transplanted through the jugular vein or the carotid artery or by stereotactic intraventricular delivery to the infarction models 1 week after the cerebral infarction was established. The 'Nerve Function Score' of the model rats was recorded before and after BMSC transplantation. Brain tissue sections were examined under a fluorescence microscope. We determined that the transplanted BMSCs rescued brain function, which was indicated by a decrease in the neurological scores (P<0·05) following BMSC transplantation. The effect of BMSC transplantation was reflected in decreases in the neurological score in the intraventricular transplantation group, the carotid artery transplantation group, and the jugular vein graft group*. The transplanted BMSCs were able to migrate to the brain injury area and the cortex and survived the infarction; thus, BMSCs may promote the recovery of nerve function.

[Pluripotential of human adult stem cells and its application in reparative and reconstructive surgery].

OBJECTIVE: To explore the pluripotential and possible clinical application of adult stem cells. METHODS: The original articles on adult stem cells were extensively reviewed and the recent advances were summed up. RESULTS: Adult stem cells were located at different tissues of human beings and had the pluripotentiality of self-renewal and differentiation. Some adult stem cells, such as in marrow, nerve, muscle, fat, skin, liver, tissues, had the ability to differentiate into the unrelated cell type. CONCLUSION: The pluripotential, ubiquitous distribution and plasticity of adult stem cells offered a new way in regeneration medicine, such as cell therapy and tissue engineering.