TY - JOUR
T1 - Total body irradiation selectively induces murine hematopoietic stem cell senescence
AU - Wang, Yong
AU - Schulte, Bradley A.
AU - LaRue, Amanda C.
AU - Ogawa, Makio
AU - Zhou, Daohong
PY - 2006/1/1
Y1 - 2006/1/1
N2 - Exposure to ionizing radiation (IR) and certain chemotherapeutic agents not only causes acute bone marrow (BM) suppression but also leads to long-term residual hematopoietic injury. This latter effect has been attributed to damage to hematopoietic stem cell (HSC) self-renewal. Using a mouse model, we investigated whether IR induces senescence in HSCs, as induction of HSC senescence can lead to the defect in HSC self-renewal. It was found that exposure of C57BL/6 mice to a sublethal dose (6.5 Gy) of total body irradiation (TBI) resulted in a sustained quantitative and qualitative reduction of LKS + HSCs. In addition, LKS+ HSCs from irradiated mice exhibited an increased expression of the 2 commonly used biomarkers of cellular senescence, p16Ink4a and SA-β-gal. In contrast, no such changes were observed in irradiated LKS- hematopoietic progenitor cells. These results provide the first direct evidence demonstrating that IR exposure can selectively induce HSC senescence. Of interest, the induction of HSC senescence was associated with a prolonged elevation of p21Cip1/Waf1, p19Arf, and p16Ink4a mRNA expression, while the expression of p27Kip1 and p18Ink4c mRNA was not increased following TBI. This suggests that p21Cip1/Waf1, p19Arf, and p16Ink4a may play an important role in IR-induced senescence in HSCs.
AB - Exposure to ionizing radiation (IR) and certain chemotherapeutic agents not only causes acute bone marrow (BM) suppression but also leads to long-term residual hematopoietic injury. This latter effect has been attributed to damage to hematopoietic stem cell (HSC) self-renewal. Using a mouse model, we investigated whether IR induces senescence in HSCs, as induction of HSC senescence can lead to the defect in HSC self-renewal. It was found that exposure of C57BL/6 mice to a sublethal dose (6.5 Gy) of total body irradiation (TBI) resulted in a sustained quantitative and qualitative reduction of LKS + HSCs. In addition, LKS+ HSCs from irradiated mice exhibited an increased expression of the 2 commonly used biomarkers of cellular senescence, p16Ink4a and SA-β-gal. In contrast, no such changes were observed in irradiated LKS- hematopoietic progenitor cells. These results provide the first direct evidence demonstrating that IR exposure can selectively induce HSC senescence. Of interest, the induction of HSC senescence was associated with a prolonged elevation of p21Cip1/Waf1, p19Arf, and p16Ink4a mRNA expression, while the expression of p27Kip1 and p18Ink4c mRNA was not increased following TBI. This suggests that p21Cip1/Waf1, p19Arf, and p16Ink4a may play an important role in IR-induced senescence in HSCs.
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U2 - 10.1182/blood-2005-04-1418
DO - 10.1182/blood-2005-04-1418
M3 - Article
C2 - 16150936
AN - SCOPUS:30144439380
SN - 0006-4971
VL - 107
SP - 358
EP - 366
JO - Blood
JF - Blood
IS - 1
ER -