Immunohistochemical analysis and role of secreted frizzled-related protein-4 in polycystic ovary-induced rat

The role of Wnt signaling and its antagonist; secreted Frizzled Related Protein type 4 [sFPR4] was reported in rodent ovarian follicular development. This study examines immunolocalization of sFRP4 in ovaries of polycystic ovary [PCO] rat model and evaluates its role in follicular growth arrest and its premature differentiation. PCO was induced with daily administration of testosterone propionate [TP] for 1 to 4 weeks while normal control rats were injected only with vehicle. The ovaries underwent histological examination, immunohistochemical analysis of sFRP4 and steroidogenic acute regulatory protein [StAR] and apoptosis analysis. Four-week TP treatment significantly increased the primordial follicles, and significantly decreased the preantral and antral follicles compared to one week TP treatment. TP-treated animals had concomittantly, significant increase of sFPR4 immunoexpression in primordial, primary and preantral follicles as compared to one week TP-treated animals and control groups. Furthermore, sFRP4 immunostaining strongly co-localized in apoptotic granulosa cells. Interestingly, increased sFRP4 immunostaining was associated with increased StAR immunoexpression in follicular theca layer and stroma in four weeks TP-treated rats compared to one week TP-treated rats and control groups. Our data showed a highly significant association between sFRP4 expression and apoptosis in ovaries of four week TP-treated animals. Moreover, co-localization of StAR and sFRP4 could suggest that sFRP4 may play a role in premature differentiation of follicles

[Effects of lithium chloride on in vitro proliferation rate of rat marrow-derived mesenchymal stem cells]

To evaluate the effects of lithium chloride on MSCs in vitro expansion rate. In this experimental study, bone marrow from 8 rats was plated at 5x105-cells/cm2 in the presence of 1,2,5,7 and 10 mM Lithium chloride and expanded through 3 passages. Twelve days after initiatial culture, the cells of different groups were stained with crystal violet in order to compare the number and diameter of the colonies. Also the cells from different groups were compared in terms of the population doubling [PD] during the 1-3 passages. Different groups of growth curves were plotted for the third passage cells. At the end of cultivation period, the cells were examined wheatear they could differentiate into bone and adipose cells. The Number and diameter of the colonies in primary cultures treated with 5mM lithium chloride were significantly higher than those of control and other groups [P<0.001]. The cell population in the culture with 5 mM lithium chloride was doubled in average 12.02 +/- 0.04 times during 1-3 passages that was significantly higher than other groups. Compared to other groups, the cells from 5 mM group were reached platue in a short time [4.9 days] [P<0.001]. Alizarin red staining for bone and oil red for adipose cells indicated that the cells in different studied groups preserved their differentiation potential. Finally, it seems that the presence of 5 mM litium chloride in the cultures of rat bone marrow cells enhances the MSC in vitro expansion rate while maintaining their bone and adipose differentiation potential