sara asalgoo

 Post traumatic stress disorder (PTSD) is an anxiety reaction, which occurs as a result of encountering a seriously traumatic event during one’s lifetime. The aim of this study was to evaluate the effect of saffron aqueous extract and crocin on spatial memory and learning with the Barnes maze in a PTSD model on male Wistar rats (Weighting 200–250 gr).  Wistar rats (n=48) were randomly divided into two groups: PTSD and non-PTSD. The PTSD group first received intra-cerebero-ventricular (ICV) administration of 10 µg/rat aqueous saffron extract, crocin or saline and then an electric foot shock. After 21 days, both groups were returned to the electric shock box in order to remember stressors without receiving any shocks. Corticosterone levels were then measured in the samples. Concurrently, a digital camera was recording the animals’ behaviors. Upon this, spatial learning and memory was assessed for five consecutive days.  The saffron extract and crocin caused a significant increase (P<0.001) in corticosterone levels and a significant reduction (P<0.05) in freezing behavior, as well as a significant difference (P<0.001) in spatial learning of the two groups.  Our results indicate the potential role of saffron aqueous extract and its active derivative (crocin) in improving behavioral symptoms and spatial learning in PTSD models.

Alzheimer’s disease (AD) is characterized by progressive neuronal loss in hippocamp. Epidermal neural crest stem cells (EPI-NCSC) can differentiate into neurons, astrocytes and oligodendrocytes. The purpose of this study was to evaluate the effects of transplanting EPI-NCSC into AD rat model. Two weeks after induction of AD by injection of Amyloid-β 1-40 into CA1 area of rat hippocamp, Y-maze and single-trial passive avoidance tests were used to show deficit of learning and memory abilities. EPI-NCSC were obtained from the vibrissa hair follicle of rat, cultured and labeled with bromodeoxyuridine. When Alzheimer was proved by behavioral tests, EPI-NCSC was transplanted into CA3 area of hippocamp in AD rat model. The staining of EPI-NCSC markers (nestin and SOX10) was done in vitro. Double-labeling immunofluorescence was performed to study survival and differentiation of the grafted cells. We showed that transplanted EPI-NCSC survive and produce many neurons and a few glial cells, presenting glial fibrillary acidic protein. Total number of granule cells in hippocamp was estimated to be more in the AD rat model with transplanted cells as compared to AD control group. We observed that rats with hippocampal damage made more errors than control rats on the Y-maze, when reward locations were reversed. Transplanted cells were migrated to all areas of hippocamp and the total number of granule cell in treatment group was equal compared to control group. Transplantation of EPI-NCSC into hippocamp might differentiate into cholinergic neurons and could cure impairment of memory in AD rat model.

Throughout life, stem cells make new cells in various tissues. Bulge region of hair follicle indicated as sources of stem cells for along times but little studies done in vitro to characterize rat bulge hair follicle stem cells. In this study bulge cells of rat hair follicle were isolated and were cultured, then morphological features of differentiated cells were studied. Also, rat hair follicle cells were assessed one and three weeks after cultivation. The result showed that two days after cell attachment to floor of plates, the cells initiate to proliferation and migration. Growth curve showed that the rate of cell proliferation at day 8 reaches its maximum level. After a week of cell culture, they had good power but after detachment were limited reproduced. Most cells in high cell density conditions and NT- 3 treated media differentiated to neural and glial lineage. Results showed that cultivated rat bulge cells, have high proliferative potential, and also could change to neural and glial like cells.

Transplants of multipotent stem cells have been shown to have a neuroprotective effect after central nervous system injury. The bulge region of the hair follicle has been reported as a putative source of hair follicle stem cells (HFSC) for many years; however, few studies have documented the properties of bulge derived cells in vitro until now. This study was conducted to isolate and culture bulge cells from rat hair follicles and to determine the morphological and biological features of the cultured cells. The bulge region of the rat whisker was isolated and cultured in Dulbecco's modified eagle medium: nutrient mixture F-12 (DMEM/F12) supplemented with epidermal growth factor (EGF), cholera toxin. Dissociated bulge stem cells were differentiated on coated substrates together with NT-3. The morphological and biological features of cultured bulge cells were observed by light microscopy and immunocytochemistry methods. Our results showed that newly proliferated cells could be observed on the 4th day after explantation. The expression of a neural progenitor marker, nestin, was seen before differentiation of the bulge cells. The differentiated cells expressed βIII-Tubulin and RIP, which are the markers of neural and glial lineages. The results indicated that the bulge cells cultured from the rat hair follicle had the characteristics of stem cells and could differentiate into neural and glial lineages.