Effect of serum containing kidney-tonifying and blood-activating Chinese herbs on the in vitro proliferation of rat bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: Bone marrow mesenchymal stem cells (MSCs) have been widely accepted by medical investigators due to their advantages including easy obtaining, minimal invasion, with infinite proliferation and multi-differential potential, and without immunological rejection in the autologous transplantation. OBJECTIVE: The goal of this study is to isolate and purify rat bone marrow MSCs in vitro, so as to observe the effects of different concentrations of serum containing kidney-tonifying and blood-activating Chinese herbs on the in vitro proliferation of rat bone marrow MSCs.DESIGN: A randomized controlled animal experiment.SETTING: Hip Center, First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine.MATERIALS Forty healthy male SD rats of SPF grade, weighing 170 to 180 g, were provided by the Laboratory Animal Center, Guangzhou University of Traditional Chinese Medicine. The protocol was performed in accordance with ethics guidelines for the use and care of animals. The involved rats were divided into 4 groups by random digit table with 10 rats in each normal control group, high-, middle-, and low-concentration groups. METHODS: This study was performed at the Laboratory Animal Center, Guangzhou University of Traditional Chinese Medicine between January and March 2005. Rat bone marrow MSCs were isolated and purified by Percoll density gradient centrifugation, and cultured in vitro to establish rat bone marrow MSCs culture system. Rats in the high-, middle-, and low-concentration groups were intragastrically administrated with 4.4, 2.2 and 1.1 g/kg serum containing kidney-tonifying and blood-activating Chinese herbs, which equaled to 20, 10 and 5 times of adult dosage, respectively. Rats in the normal control group were intragastrically administrated with purified water for 1 week. One hour after the last administration, 6 mL blood was taken from abdominal aorta of each rat under the aseptic condition. Then, it was centrifuged at 2 000 r/min for 15 minutes, and meanwhile serum was collected. 10% rat serum containing kidney-tonifying and blood-activating Chinese herbs was added to the medium in the high-, middle-, and low-concentration groups, while 10% fetal bovine serum was added in the normal control group. MAIN OUTCOME MEASURES: ① MSCs growth status; ② MSCs morphology was observed by HE staining and Giemsa's staining; ③ MSCs antigen expression was detected by an immunocytochemical method; ④ Effects of different concentrations of serum containing kidney-tonifying and blood-activating Chinese herbs on MSCs growth.RESULTS: ①The primarily cultured bone marrow MSCs began to adhere to the wall 24 hours later and 80% of them reached the confluence 7 days later. ② MSCs took appearance in long shuttle shape or polygon. These cells were little. Nuclei were located in the middle part of cells or a little deviation. The ratio of nucleus to cytoplasm was a little high. ③CD44 expression was found in the cytoplasm of mononuclear cells, and colored blue. Partial MSCs expressed c-Kit. Their cytomorphology and phenotypic expression have the characteristics of MSCs. ④Three days after serum containing kidney-tonifying and blood-activating Chinese herbal medicine being added to high-, middle-, and low-concentration groups, the number of bone marrow MSCs was dose-dependently increased as compared with that in the normal control group. CONCLUSION: Serum containing kidney-tonifying and blood-activating Chinese herbs promotes the in vitro proliferation of bone marrow MSCs.