Cell and Tissue Journal

Abstract

Abstract Aim: In this research morphological, cell culture, immunochemical and inductive properties of rat’s claw dermal cells were investigated. Material and Methods: First, the toes and fingers of rat were amputated at the point of the last joint and the amputated parts were processed for histological studies. Moreover, the dermal tissue located beneath the claw’s plate was dissected and cultured in vitro. Cultured cells at passage two or three were transferred on the slide and treated with α-smooth muscle actin (ASMA) antibody. Finally the cultured cells were stained with DiI and implanted into the vibrissae semi-follicles and ears. Results: The rat’s claw dermal cells in terms of morphological, cell culture and expression of ASMA demonstrated similarity with dermal papilla cells of hair follicles. These cells showed a bipolar spindle-shaped morphology having an extracellular matrix rich in glycosaminoglycans. Majority of the cells expressed ASMA in cytoplasm with a higher intensity in lamelopodia.  However, with respect to hair follicular dermal papilla cells, the claw dermal cells were not able to induce an ectopic epidermis to form the skin appendage.  Conclusion: The inductive capability which has been seen in hair follicle’s dermal papilla cells can not be generalized to dermal cells present in other skin appendages, including claw. Based on the results presented here, the inductive factors exist in hair follicle dermal papilla cells is not expressed in the claw dermal cells.

Abstract Plants produce a big group of secondary metabolites which are used as medicinal compounds. According to recent estimates, global market value of herbal medicines, including medicinal plants and their products, significantly has been increasing. Considering to the fact that most of the world market for medicinal plants, production and supply of secondary metabolites derived from these plants are concerned and the plant secondary metabolites are of high economic value. Chemical synthesis of these metabolites is an expensive process. So production of metabolites by different biotechnological methods such as cell culture is a useful alternative. Molecular recognition and elicitor-plant receptors interaction is a complex process requiring for signal transduction. Biotic elicitors induce secondary metabolites and hypersensitive responses by activation of defense mechanisms. Manipulation of cell culture media by elicitors is an important strategy for inducing secondary metabolism and production of valuable metabolites. Molecular recognition and elicitor-plant receptors interaction is a complex process requiring for signal transduction. Following perception of elicitor signals, rapid defense responses can be organized as follows: increase of ionic currents across the plasma membrane, reactive oxygen species (ROS) production, activation of defense gene expression, structural changes in the cell wall and phytoalexin production. In this study, different aspects of increasing the production of secondary metabolites in cell culture of plants by biotic elicitors is investigated.  

Abstract Aim: During embryonic development, both bird’s feather follicle and mammal’s hair follicle originate by a similar manner, the aim of this research was to access and compare histology, cell growth potential and inductive properties of papilla cells this organs for initiating dermal-epidermal interactions.
Material and Methods: Feather and hair follicles were provided from house pigeons and PVG rats, respectively. Some of the follicles were processed for histological examination whiles others were used to dissect out their dermal papilla. The dissected dermal papillae were cultured in vitro. The cultured cells were then implanted into papilla-depleted follicles. After 28 days the implanted follicles were histologically examined.
Results: Histological surveys revealed that despite some distinct differences, both follicles (feather and hair) share a similar histological structure. Hair’s dermal papilla cells showed a greater rate of growth as well as a higher and denser cell aggregation when compared to that of feather follicles. In contrast to hair papilla, the feather papilla cells were not able to grow a hair fiber in implanted follicles.
Conclusion: Despite similarities in embryonic development, histological structure and cell growth in vitro, it seems that the signals coming from cultured dermal cells of a mature bird are not able to be understood by hair follicle epidermal cells and can not initiate dermal-epidermal interactions

Abstract Aim: “The bulge activation hypothesis” has recently provided significant interest in the hair follicle cycle. One facet of this hypothesis suggests that the epithelial cells located at the base of the follicle are ‘transient amplifying, that limit the duration of the follicle’s growth phase. In this study, we investigate the pattern of cell division and proliferation of these cells and compared with those from upper part of follicle. Material and methods: To fulfill this task, epidermal cells from lower and upper vibrissa follicles were cultured after isolation and growth characteristics of these two cell types were measured and recorded over a period of weeks. Results: Data provided here demonstrated that epidermal cells from lower region of follicle normally attached to the substrate and started dividing more slowly than their counterparts from the upper part of the follicle. In addition, although the majority of the basal cells failed to grow for extended periods and underwent terminal differentiation, a small subset of these cells grew as large single colonies for more than 10 weeks and they were able to be passaged several times. Conclusion: Contrary to the current dogma, we here showed that, at least in culture medium, some of basal hair follicle cells have a proliferative capacity which is much further than duration of the growth phase of follicle. Therefore, the termination of growth phase can not be related to the replicative potential of these cells.