RESUMO
Background: Bone marrow-derived mesenchymal stem cells [BMMSCs] transplantation has been considered as a promising milestone in liver fibrosis treatment. However, low amounts of homing are a major obstacle. We aimed to investigate the role of melatonin pretreatment in BMMSC homing into experimental liver fibrosis
Methods: BMMSCs were obtained, grown, propagated and preconditioned with 5 µM melatonin and analyzed for multipotency and immunophenotypic features at passage three. The cells were labelled with CM-Dil and infused into the rats received the i.p. injection of carbon tetrachloride [CCl4] for five weeks to induce liver fibrosis. Animals were divided into two groups: One group received BMMSCs, whereas the other group received melatonin-pretreated BMMSCs [MT-BMMSCs]. After cell injection at 72 h, animals were sacrificed, and the liver tissues were assessed for further evaluations: fibrosis using Masson's trichrome and hematoxylin and eosin staining and homing using fluorescent microscopy and flow cytometry
Results: BMMSCs and MT-BMMSCs expressed a high level of CD44 but low levels of CD11b, CD45 and CD34 [for all P
Conclusion: This study indicates the improved homing potential of BMMSCs in pretreatment with melatonin. Therefore, this strategy may represent an applied approach for improving the stem cell therapy of liver fibrosis
RESUMO
Background: Considering nitric oxide [NO] has an important role in many biologic processes of cells and tissues such as in the digestive system. In this system nitric oxide acts as a second messenger in pathological and physiological events in gastrointestinal region
We investigated the effects of L-NG-Nitro arginine Methyl Ester [L-NAME] as the NO formation inhibitor on parietal cells of stomach in pregnant rats
Methods: Twenty four female rats with eight weeks old and 200-250 g weight were prepared and used in this study
After matting of the female rats with the male rats, time of observing vaginal plaque considered as the zero day of pregnancy. Then the animals were divided into three groups of studying. Each group was containing eight rats. In this study, except the control group, the saline group received 2 ml/kg normal saline and experimental group received 20 ml/kg L-NAME interaperitoneally [IP], respectively on third, fourth, and fifth days of pregnancy for evaluation of its effects. On the 18th day of pregnancy, after anesthesia with ether, the animals were killed and dissected and the laparotomy was performed to separate the mother's stomach
Then, the stomach was fixed in 10% formalin and after tissue passage, the sections were stained with Hematoxylin-Eosin [HandE]
Then the changes of count and diameter in parietal cells were observed via light microscopy and Image Tools III
Results: This study after analysis showed the significant changes in parietal cells count [mean 61.3+/-4.32] and its diameters [mean 16.12+/-1.18 m] in L-NAME group in comparison to control and the sham groups in pregnant rats [P<0.05]
Conclusion: Results of this study showed L-NAME with effects on NO synthesis can reduce parietal cells count and increase its diameter in pregnant rats and has destructive effects on structure of stomach parietal cells in pregnancy rats