Astragalus Polysaccharide Attenuated Iron Overload-Induced Dysfunction of Mesenchymal Stem Cells via Suppressing Mitochondrial ROS.
OBJECTIVE
Bone marrow-derived mesenchymal stem cells (BMSCs) have the ability to differentiate into multilineage cells such as osteoblasts, chondrocytes, and cardiomyocytes. Dysfunction of BMSCs in response to pathological stimuli participates in the development of diseases such as osteoporosis. Astragalus polysaccharide (APS) is a major active ingredient of Astragalus membranaceus, a commonly used anti-aging herb in traditional Chinese medicine. The aim of this study was to investigate whether APS protects against iron overload-induced dysfunction of BMSCs and its underlying mechanisms.


METHODS
BMSCs were exposed to ferric ammonium citrate (FAC) with or without different concentrations of APS. The viability and proliferation of BMSCs were assessed by CCK-8 assay and EdU staining. Cell apoptosis, senescence and pluripotency were examined utilizing TUNEL staining, β-galactosidase staining and qRT-PCR respectively. The reactive oxygen species (ROS) level was assessed in BMSCs with a DCFH-DA probe and MitoSOX Red staining.


RESULTS
Firstly, we found that iron overload induced by FAC markedly reduced the viability and proliferation of BMSCs, but treatment with APS at 10, 30 and 100 μg/mL was able to counter the reduction of cell proliferation. Furthermore, exposure to FAC led to apoptosis and senescence in BMSCs, which were partially attenuated by APS. The pluripotent genes Nanog, Sox2 and Oct4 were shown to be downregulated in BMSCs after FAC treatment, however APS inhibited the reduction of Nanog, Sox2 and Oct4 expression. Further study uncovered that APS treatment abrogated the increase of intracellular and mitochondrial ROS level in FAC-treated BMSCs.


CONCLUSIONS
Treatment of BMSCs with APS to impede mitochondrial ROS accumulation can remarkably inhibit apoptosis, senescence, and the reduction of proliferation and pluripotency of BMSCs caused by FAC-induced iron overload.
Department of Orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, China.
Fan
F
Yang
Gege
G
Yan
Yuan
Y
Li
Zhenbo
Z
Han
Lai
L
Zhang
Simon
S
Chen
Chao
C
Feng
Qi
Q
Huang
Fengzhi
F
Ding
Ying
Y
Yu
Chongwei
C
Bi
Benzhi
B
Cai
Lei
L
Yang
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D027883:Astragalus Plant / Q000737:chemistry*; D001854:Bone Marrow Cells / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation; D002470:Cell Survival / Q000187:drug effects; D016922:Cellular Senescence / Q000187:drug effects; D005290:Ferric Compounds / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D005786:Gene Expression Regulation; D008297:Male; D059630:Mesenchymal Stem Cells / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D000071317:Nanog Homeobox Protein / Q000235:genetics / Q000378:metabolism; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D061251:Primary Cell Culture; D000644:Quaternary Ammonium Compounds / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors* / Q000378:metabolism; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
D005290:Ferric Compounds; D000071317:Nanog Homeobox Protein; C475540:Nanog protein, mouse; D050814:Octamer Transcription Factor-3; D011134:Polysaccharides; C494174:Pou5f1 protein, mouse; D000644:Quaternary Ammonium Compounds; D017382:Reactive Oxygen Species; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse; C013531:ferric ammonium citrate