Document Type : Original Article
Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran;Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
Department of Hematology, Faculty of Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
4Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
The peroxisome proliferator-activated receptors (PPARs) are a group of nu- clear receptor proteins whose functions as transcription factors regulate gene expres- sions. PPARs play essential roles in the regulation of cellular differentiation, development, and metabolism (carbohydrate, lipid, protein), and tumorigenesis of higher organisms. This study attempts to determine the effect of baicalin, a PPARγ activator, on erythroid differentiation of cluster of differentiation 133+(CD133+) cord blood hematopoietic stem cells (HSCs).
Materials and Methods
In this experimental study, in order to investigate the effects of the PPARγ agonists baicalin and troglitazone on erythropoiesis, we isolated CD133+ cells from human umbilical cord blood using the MACS method. Isolated cells were cultured in erythroid-inducing medium with or without various amounts of the two PPARγ activa- tors (baicalin and troglitazone). Erythroid differentiation of CD133+cord blood HSCs were assessed using microscopic morphology analysis, flow cytometric analysis of erythroid surface markers transferrin receptor (TfR) and glycophorin A (GPA) and bycolony forming assay.
Microscopic and flow cytometric analysis revealed the erythroid differentiation of CD133+cord blood HSCs under applied erythroid inducing conditions. Our flow cytometric data showed that the TfR and GPA positive cell population diminished significantly in the presence of either troglitazone or baicalin. The suppression of erythroid differentiation in response to PPARγ agonists was dose-dependent. Erythroid colony-forming ability of HSC decreased significantly after treatment with both PPARγ agonists but troglitazone had a markedly greater effect.
Our results have demonstrated that PPARγ agonists modulate erythroid dif- ferentiation of CD133+HSCs, and therefore play an important role in regulation of normal erythropoiesis under physiologic conditions. Thus, considering the availability and applica- tion of this herbal remedy for treatment of a wide range of diseases, the inhibitory effect of baicalin on erythropoiesis should be noted.