The Impact of Chrysin on The Folliculogenesis and Ovarian Apoptosis in Ischemia-Reperfusion Injury in The Rat Model.

BACKGROUND: The ovarian Ischemia/reperfusion is one of the gynecological emergency concerns that may lead to the ovary damage and folliculogenesis. The present research aimed to evaluate the impact of the Chrysin (CH) on the ischemia-reperfusion (I/R) injury in the rat model. MATERIALS AND METHODS: In this experimental research, 48 adult female rats, 8 weeks age and 180-200 g weight, have been categorized into 6 equal groups (n=8) including one sham and 5 ovarian torsion groups (OT+CH groups) that received different treatments. Each group has been treated 30 min before detorsion with gavage of CH or normal saline for 1 week and pregnant mare serum gonadotropin (PMSG) has been injected on the day 5 for initiating folliculogenesis. Finally, bio-chemical, molecular, histopathological, apoptotic and hormonal evaluations were performed. RESULTS: The anti-oxidant enzyme, superoxide dismutase and glutathione peroxidase, ameliorated in the ovarian tissues of the OT+CH groups in comparison with the OT group (P<0.001). Moreover, the level of serum Luteinizing hormone considerably declined and estradiol level (P<0.001), partly enhanced in the rats treated with CH in comparison with the ones in the OT group (P<0.05). In addition, histopathological scores of the OT+CH groups ameliorated in comparison with the OT group scores (P<0.05). Furthermore, the expression Caspase-3 and Bax genes were significantly increased while the expression of Bcl-2 was notably decreased in the OT group in comparison with the sham group (P<0.05). CONCLUSION: Here, it seems that CH is possibly beneficial for the protection of ovaries against reperfusion injury and ischemia.

Effects of hypothermia and pentoxifylline on the adnexal torsion/detorsion injuries in a rat testis model.

This study was designed to investigate the effects of separate and combined administration of hypothermia and pentoxifylline to preserve the effects on the testicles in an experimental model of testicular torsion/ detorsion injuries in rats. Forty male adult Wistar rats were randomly divided into five groups, control, torsion/detorsion (TD), torsion/detorsion/hypothermia (TD+ICE), torsion/detorsion received of pentoxifylline (40mg/kg, ip) (TD+PTX) and torsion/detorsion/hypothermia/PTX (TD+ICE+PTX). Left testicular torsion (TT) was performed for 4 and half hours, and ice fragments have been used at the beginning of torsion. After the reperfusion period (a week), oxidative maker's serum levels, testosterone hormone, sperm parameters, and histopathological and gene expression evaluations have been performed. Significant adverse changes were observed in the TD group for histological variables, sperm count, oxidative marker, testosterone hormone, Bax, BCL2 and caspase-3 expression. The parameters studied in the group receiving PTX improved in comparison with the TD group, while macroscopical parameters of both the hypothermia and PTX+ICE groups were not different compared with the TD group. The results revealed that PTX, as an antioxidant component, was protective against testicular torsion, while hypothermia and hypothermia plus PTX did not exhibit this property, which may have been due to the duration of hypothermia (4 hr) or reperfusion period.

Telomerase activity and telomere on stem progeny senescence.

The end of linear chromosomes is formed of a special nucleoprotein heterochromatin structure with repetitive TTAGGG sequences called telomere. Telomere length is regulated by a special enzyme called telomerase, a specific DNA polymerase that adds new telomeric sequences to the chromosome ends. Telomerase consists of two parts; the central protein part and the accessory part which is a RNA component transported by the central part. Regulation of telomere length by this enzyme is a multi-stage process. Telomere length elongation is strongly influenced by the level of telomerase and has a strong correlation with the activity of telomerase enzyme. Human Telomerase Reverse Transcriptase (hTERT) gene expression plays an important role in maintaining telomere length and high proliferative property of cells. Except a low activity of telomerase enzyme in hematopoietic and few types of stem cells, most of somatic cells didn't showed telomerase activity. Moreover, cytokines are secretory proteins that control many aspects of hematopoiesis, especially immune responses and inflammation. Also, the induction of hTERT gene expression by cytokines is organized through the PI3K/AKT and NF/kB signaling pathways. In this review we have tried to talk about effects of immune cell cytokines on telomerase expression/telomere length and the induction of telomerase expression by cytokines.

Oryzatensin-stimulated PBMCs Increase Cancer Progression In-vitro.

Oryzatensin (ORZ) can reduce potentially IFN-γ secretion by natural killer (NK) cells. Therefore, current study was designed to evaluate the effects of ORZ treatment on peripheral blood mono-nuclear cells (PBMCs) cytokine secretion, proliferation and also to evaluate vascular endothelial growth factor (VEGF) and Matrix Metalloproteinase 9 (MMP-9) expression in HEP-G2 cell line after culture with ORZ-stimulated PBMCs. In this ex-vivo study, PBMCs from apparently healthy male volunteers (n=25) aged 20-30 were isolated by ficoll density gradient. Tetrazolium colorimetric test (MTT assay), ELISA test and real time PCR were performed to evaluate PBMCs proliferation, PBMCs cytokine secretion and the genes expression accordingly. The results of MTT assay showed that ORZ significantly stimulated proliferation of the isolated PBMCs. The results also indicated that ORZ treatment significantly decrease and increase IFN-γ and IL-4 secretion by isolated PBMCs, respectively. Also, VEGF and MMP-9 expression significantly increased in HEP-G2 cells after culture with ORZstimulated PBMCs. The previous studies have introduced ORZ-like peptide for pharmacological purpose and in this study we get to the conclusion that the administration of this peptide may change the immune system response and sensitize target populations to cancer.

Key Immune Cell Cytokines Affects the Telomere Activity of Cord Blood Cells In vitro.

PURPOSE: Telomere is a nucleoprotein complex at the end of eukaryotic chromosomes and its length is regulated by telomerase. The number of DNA repeat sequence (TTAGGG)n is reduced with each cell division in differentiated cells. The aim of this study was to evaluate the effect of SCF (Stem Cell Factor), Flt3 (Fms- Like tyrosine kinase-3), Interleukin-2, 7 and 15 on telomere length and hTERT gene expression in mononuclear and umbilical cord blood stem cells (CD34+ cells) during development to lymphoid cells. METHODS: The mononuclear cells were isolated from umbilical cord blood by Ficoll-Paque density gradient. Then cells were cultured for 21 days in the presence of different cytokines. Telomere length and hTERT gene expression were evaluated in freshly isolated cells, 7, 14 and 21 days of culture by real-time PCR. The same condition had been done for CD34+ cells but telomere length and hTERT gene expression were measured at initial and day 21 of the experiment. RESULTS: Highest hTERT gene expression and maximum telomere length were measured at day14 of MNCs in the presence of IL-7 and IL-15. Also, there was a significant correlation between telomere length and telomerase gene expression in MNCs at 14 days in a combination of IL-7 and IL-15 (r = 0.998, p =0.04). In contrast, IL-2 showed no distinct effect on telomere length and hTERT gene expression in cells. CONCLUSION: Taken together, IL-7 and IL-15 increased telomere length and hTERT gene expression at 14 day of the experiment. In conclusion, it seems likely that cells maintain naïve phenotype due to prolonged exposure of IL-7 and IL-15.

Key immune cell cytokines have a significant role in the expansion of CD26 population of cord blood mononuclear cells.

BACKGROUND: Umbilical cord blood expresses cluster of differentiation (CD) 26, a fraction of CD34 + cells, negatively regulating in vivo homing and engraftment of hematopoietic stem cells. CD26 is highly expressed in various cells such as HSCs, immune cells, fibroblasts, and epithelial cells. It has been shown that inhibition of the CD26 on CD34 + cells improve the efficiency of transplantation of hematopoietic stem and progenitor cells. This study aimed to investigate the effect of key immune cell cytokines on CD26 expansion. MATERIAL AND METHODS: Cord blood mononuclear cells were cultured for 21 days using the stem cell factor, fetal liver tyrosine kinase 3 (Flt3) ligand (FL), interleukin (IL) 2, IL7, and IL15. Harvested cells were analyzed by flow cytometry at distinct time points. RESULTS: Our results showed that utilization of IL7 significantly improved the expression of total CD26 + cells (8.6-fold higher). When either IL2 or IL15 were added to the culture, the expression also improved 2.5-fold. The IL2 and IL7 showed significant effect on the expansion of both the CD26 + and CD26 fractions of the CD34 + cells. However, the effects of IL15 on CD26 + and CD26 -expansion were similar. CONCLUSION: Taken together, our data suggested that using IL7 causes higher proliferation of CD26 cells in comparison to that seen under other culture conditions.

CD26+ Cord Blood Mononuclear Cells Significantly Produce B, T, and NK Cells.

BACKGROUND: Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cell transplantation (HSCT), used in Leukemia treatment. CD26+ cells, a fraction of CD34+cells, are a major population of UCB cells which negatively regulate the in vivo homing and engraftment of HSCs. CD26 is highly expressed in various cells such as HSCs, immune cells, fibroblasts, and epithelial cells. It has been shown that the inhibition of the CD26 on CD34+ cells improves the efficiency of Hematopoietic Stem and Progenitor Cell (HPC) transplantation. OBJECTIVE: To evaluate the relationship between the production of B, T, and NK cells from the CD26+ fraction of cord blood mononuclear cells. METHODS: Cord blood mononuclear cells were cultured for 21 days using different combinations of stem cell factors (SCF), Flt3 ligand (FL), IL-2, IL-7, and IL-15. The harvested cells were then analyzed by flowcytometry every week for 21 days. RESULTS: T cell differentiation from CD26 subset of cord blood mononuclear cells increased by using IL-2 and IL-7. Our data showed that IL-2 and IL-7 significantly affected the generation of B cells from CD26 positive cord blood mononuclear cells. On the other hand, NK (NKp46+) derived CD26+ cells increased by IL-15 and IL-2. CONCLUSION: Taking all into account, we conclude that B, T, and NK cells can differentiate from the CD26+ subset of mononuclear cord blood cells by using key regulatory cytokines.