Migration of bone marrow-derived very small embryonic-like stem cells toward an injured spinal cord

Objective: Bone marrow [BM] is one of the major hematopoietic organs in postnatal life that consists of a heterogeneous population of stem cells which have been previously described. Recently, a rare population of stem cells that are called very small embryonic-like [VSEL] stem cells has been found in the BM. These cells express several developmental markers of pluripotent stem cells and can be mobilized into peripheral blood [PB] in response to tissue injury. In this study we have attempted to investigate the ability of these cells to migrate toward an injured spinal cord after transplantation through the tail vein in a rat model

Materials and Methods: In this experimental study, VSELs were isolated from total BM cells using a fluorescent activated cell sorting [FACS] system and sca1 and stage specific embryonic antigen [SSEA-1] antibodies. After isolation, VSELs were cultured for 7 days on C2C12 as the feeder layer. Then, VSELs were labeled with 1,1´-dioctadecyl-3,3,3´,3´- tetramethylindocarbocyanine perchlorate [DiI] and transplanted into the rat spinal cord injury [SCI] model via the tail vein. Finally, we sought to determine the presence of VSELs in the lesion site

Results: We isolated a high number of VSELs from the BM. After cultivation, the VSELs colonies were positive for SSEA-1, Oct4 and Sca1. At one month after transplantation, real-time polymerase chain reaction analysis confirmed a significantly increased expression level of Oct4 and SSEA-1 positive cells at the injury site

Conclusion: VSELs have the capability to migrate and localize in an injured spinal cord after transplantation

Evaluation of effect of oleuropein on skin wound healing in aged male balb/c mice

Olive oil and olive leaf extract are used for treatment of skin diseases and wounds in Iran. The main component of olive leaf extract is Oleuropein. This research is focused on the effects of Oleuropein on skin wound healing in aged male Balb/c mice. In this experimental study, Oleuropein was provided by Razi Herbal Medicine Institute, Lorestan, Iran. Twenty four male Balb/c mice, 16 months of age, were divided equally into control and experimental groups. Under ether anesthesia, the hairs on the back of neck of all groups were shaved and a 1 cm long full-thickness incision was made. The incision was then left un-sutured. The experimental group received intradermal injections with a daily single dose of 50 mg/kg Oleuropein for a total period of 7 days. The control group received only distilled water. On days 3 and 7 after making the incision and injections, mice were sacrificed, and the skin around incision area was dissected and stained by hematoxylin and eosin [H and E] and Van Gieson's methods for tissue analysis. In addition, western blot analysis was carried out to evaluate the level of vascular endothelial growth factor [VEGF] protein expression. The statistical analysis was performed using SPSS [SPSS Inc., Chicago, USA]. The t test was applied to assess the significance of changes between control and experimental groups. Oleuropein not only reduced cell infiltration in the wound site on days 3 and 7 post incision, but also a significant increase in collagen fiber deposition and more advanced re- epithelialization were observed [p<0.05] in the experimental group as compared to the control group. The difference of hair follicles was not significant between the two groups at the same period of time. Furthermore, western blot analysis showed an increased in VEGF protein level from samples collected on days 3 and 7 post-incision of experimental group as compared to the control group [p<0.05]. These results suggest that Oleuropein accelerates skin wound healing in aged male Balb/c mice. These findings can be useful for clinical application of Oleuropein in expediting wound healing after surgery

Antioxidant role of oleuropein on midbrain and dopaminergic neurons of substantia nigra in aged rats

Oleuropein is a phenolic compound which is present in the olive leaf extract. The purpose of the present study was to investigate the neuroprotective effect of oleuropein as an antioxidant agent on the substantia nigra in aged rats. Twenty 18-month-old Wistar rats [450-550 g] were randomly divided into control and experimental groups. The experimental group received a daily single dose of 50 mg/kg of oleuropein by oral gavage for 6 months. The control group received only distilled water. All rats were sacrificed two hours after the last gavage and the brains were removed and midbrains were cut. One part of the midbrains were homogenized and centrifuged. The tissue supernatant was assayed for lipid peroxidation [LPO] and antioxidant enzyme activities. The other part of midbrains fixed and embedded in paraffin, then processed for Nissl and immunohistochemistry [IHC] staining. Data was analyzed using SPSS by t-test. Differences were considered significant for P<0.05. The level of LPO in midbrain of the rats was decreased significantly in the experimental group, but superoxide dismutase, catalase and glutathione peroxidase activities were increased in experimental group compared to control group [P<0.05]. Morphometric analyses showed significantly that the experimental group had more neurons in substantia nigra pars compacta [SNc] either in Nissl or IHC staining when compared to control [P<0.05]. The results of the present study indicate that treatment of the old rats with oleuropein reduces the oxidative damage in SNc by increasing the antioxidant enzyme activities

Neuroprotective effect of exogenous melatonin on dopaminergic neurons of the substantia nigra in ovariectomized rats

Melatonin has receptors in substantia nigra pars compacta [SNc] and regulates development of dopaminergic [DA] neurons. This study was undertaken to determine ability of melatonin to protect SNc dopaminergic neuron loss induced by estrogen deficiency in ovariectomized rats. Female rats were randomized into four groups of seven each: control, ethanol sham, ovariectomy [ovx] and ovx with melatonin [ovx + m]. In ovx, ovaries were removed. Ovx + m group was intraperitoneally injected with melatonin for 10 days, while the ethanol sham group received only ethanol. All rats were perfused with 4% paraformaldehyde, midbrains removed, fixed and paraffin embedded, then processed for Nissl and tyrosine hydroxylase staining [IHC]. Ten sections of SNc in Nissl and IHC staining were analyzed in each animal, Nissl stained and tyrosine hydroxylase [TH] immunoreactive cells were counted in five experimental groups randomly. Data was analyzed using SPSS by ANOVA and /-test. Differences were considered significant for P<0.05. There was less cell number in ovx compared to control and ethanol sham groups significantly [P<0.001]. The ovx + m group had more cells than the ovx group in the SNc significantly [P<0.001]. Furthermore, there was significant decrease of TH positive cell number in the ovx group compared to control and ethanol sham groups [P<0.05]. The number of TH immunoreactive cells-was higher in ovx + m compared to the ovx group [P<0.05]. These findings can be compared with human and used in clinical application for prevention of DA neuron death of SNc after ovariectomy

Morphometric evaluation of seminiferous tubules in aged mice testes after melatonin administration

Melatonin, the pineal gland hormone as a direct or indirect antioxidant and free radical scavenger, is involved in the process of both aging and age-related diseases. This study investigates the effects of melatonin on the histology of testicular seminiferous tubules in aged mice. Twenty male, white mice, aged 16 months, that weighed 20-23 gr were equally divided into control and experimental groups. The experimental group was intraperitoneally injected with a daily single dose of 10 mg/kg melatonin for 14 days. The control group received only saline. Six days after the last injection, all mice were sacrificed and the testes were excised and processed for light microscope observation. In the morphometric study, we evaluated testicular seminiferous tubule parameters such as height of germinal epithelium, seminiferous tubule diameter, thickness of interstitial connective tissue and spermatogenesis index [SI]. SPSS software and student's t-test analyzed all parameters to assess the significance of changes between control and experimental groups. Melatonin-treated mice had seminiferous tubules with a wide lumen lined by low height germinal epithelium. The interstitial connective tissue thickened significantly in the experimental group [p<0.05], tubular diameter and germinal epithelium height decreased significantly [p<0.01], and the SI reduced compared to the control group [p<0.001]. The results of this study showed the disadvantages of melatonin on seminiferous tubules of aged mice testes

Amiodarone induced morphological changes in rabbit pneumocytes

Amiodarone as an iodinated benzofuran derivative is a potent antiarrhythmic agent currently used for the treatment of ventricular arrhythmias. Pulmonary toxicity is one of the complications of Amiodarone therapy. The aim of this study was to determine the toxicity of Amiodarone for pneumocytes. 14 male white New Zealand rabbits were divided in a control group and an experimental group. The experimental group was subjected to intra peritoneal injection with a single daily dose of 80 mg/kg Amiodarone for two weeks. The control group received only normal saline. At the end of the injection period, the two groups were anesthetized and perfused with Karnovsky fixative. The lung tissue was removed and fixed, then prepared for light and electron microscope studies. Morphometric studies were made on sections to find nucleus profile dimensions. Light microscope observation showed acute changes in the alveolus including congestion of alveolar capillaries and infiltration of red blood cells [RBCs] into the lumen of the alveoli. Electron microscope study of lung tissue revealed abnormal inclusion bodies within type II and I pneumocytes. The micrographs also showed the presence of vacuoles in 5% of the type II pneumocytes. Morphometric studies showed that the nucleus of the cells in the experimental group were smaller than in the control group [p < 0.01]. These results indicate that Amiodarone administration can cause damage to pnuemocytes and the alveolus of rabbit lung, so the effectiveness of Amiodarone in long term treatment of heart failure patients is limited because of the development of lung toxicity