Page 11 - X. Stem cell biology
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Ablation of Sirt1 in the Non-Hematopoietic Bone Marrow Microenvironment
Is Not Required for Hematopoietic Stem Cell Function in the Adult Mice
Suyeon Woo , Jayoung Kim , Hee Seon Choi , Dongjun Lee 1*
1
1
1
1 Department of Convergence Medicine, Pusan National University, Korea
Introduction
SIRT1 is known as a histone deacetylase, performs a wide variety of function in biological systems.
It has been reported that SIRT1 is relevant to stem cell homeostasis including cell proliferation, differentiation, apoptosis, and
inflammatory responses.
Also this SIRT1 plays a important role in delay aging, extending life span and prevent aging-related in response to mitochondrial
metabolic.
METHODS
Animals
- Ocn-Cre transgenic mice and floxed Sirt1 mice
qRT-PCR
Resveratrol treatments
- BM cells treated 50μM Resveratrol for 24h prior to flow cytometry
Flow cytometric analysis
- BM cells were collected from femurs and tibias by flushing with FACS buffer. Peripheral blood cells were collected from the tail vein.
White blood cell preparation were obtained after lysing red blood cells with an ACK lysis buffer.
RESULTS
1. Resveratrol modulates the pools of HSPCs. Figure 1.
The frequencies of Lin-Sca1+ckit+ cells(LSK), LT-HSCs (Lin - 0.3 ** 0.04 ** 0.06 ** 0.20 **
Sca1 cKit CD150 Cd48 ), ST-HSCs (Lin Sca1 cKit CD150 - 0.03 0.15
-
+
+
+
+
+
-
CD48 ), MPP (Lin Sca1 cKit CD48 ) cells after Resveratrol % LSK in BM 0.2 % LT-HSC in BM 0.02 % ST-HSC in BM 0.04 % MPP in BM 0.10
-
+
+
+
-
treatment (n=5) are significantly decreased (Figure 1). 0.1 0.01 0.02 0.05
2. No changes in white blood cells, hemoglobin, and 0.0 Ct Res Vehicle: Ct Res 0.00 0.00
0.00
platelets counts of Sirt1 △/△ mice. Vehicle: Vehicle: Ct Res Vehicle: Ct Res
Figure 2.
Sirt1 deletion in the BM niche demonstrated no 15 20
differences in WBCs, lymphocytes, and platelets (Figure 2). n.s. 15 n.s. 2000 n.s.
1500
3. Sirt1 deletion is dispensable for maintaining 10 6 /ml 10 n.s. n.s. HGB (g/dl) 10 PLT (10 6 /ml) 1000
mature hematopoietic lineage cells, hematopoietic 5 n.s. +/+ 5 +/+ 500 +/+
stem and progenitor cells. 0 Δ/Δ 0 Δ/Δ 0 Δ/Δ
WBC LY NEU MO
The Sirt1 △/ △ mice did not showed differences compared Figure 3.
to wild-type mice in their ability to mature cell output in
the peripheral blood and bone marrow. 80 n.s. 80 n.s. 1.0 +/+ n.s.
0.8
No differences in hematopoietic stem and progenitor cells, 60 n.s. 60 0.6 Δ/Δ n.s. n.s.
LSK cells, CMP, GMP, MEP and CLPs were observed in the Percent PB 40 n.s. Percent BM 40 n.s. n.s. Percent BM 0.4
Sirt1 △/△ mice compared to control mice (Figure 3). 20 +/+ 20 +/+ 0.2 n.s. n.s. n.s.
0 Δ/Δ 0 Δ/Δ 0.0
Myelo B 220 CD3 M yelo B 220 C D3 HSC LSK C MP G MP MEP CLP
CONCLUSION REFERENCES
Sirt1 deletion in the hematopoietic stem and progenitor system promotes 1) A. Masumi, "Hematopoietic stem cells and response to interferon," Stem Cell Biology in
Normal Life and Diseases (K. Alimoghaddan, ed.), pp. 65-77, 2013.
hematopoietic stem and progenitor cells expansion under stress conditions. 2) E. Fuchs, T. Tumbar, and G. Guasch, "Socializing with the neighbors: stem cells and their
niche," Cell, vol. 116, no. 6, pp. 769-778, 2004.
3) F. M. Watt and W. T. Huck, "Role of the extracellular matrix in regulating stem cell fate,"
Sirt1 deletion in BM niche does not alter HSC function under stress. 4) Nature reviews Molecular cell biology, vol. 14, no. 8, pp. 467-473, 2013.
G. M. Crane, E. Jeffery, and S. J. Morrison, "Adult haematopoietic stem cell niches," Nature
Reviews Immunology, vol. 17, no. 9, p. 573, 2017.
Therefore, Sirt1 functions autonomously in stem cells but not in niche. 5) L. Dong, H. Hao, W. Han, and X. Fu, "The role of the microenvironment on the fate of adult
stem cells," Science China Life Sciences, vol. 58, no. 7, pp. 639-648, 2015.
6) S. J. Mitchell et al., "The SIRT1 activator SRT1720 extends lifespan and improves health of
mice fed a standard diet," Cell reports, vol. 6, no. 5, pp. 836-843, 2014.
To investigate the role of SIRT1 for hematopoietic stem cell function in perivascular 7) S. Özbek, P. G. Balasubramanian, R. Chiquet-Ehrismann, R. P. Tucker, and J. C. Adams, "The
evolution of extracellular matrix," Molecular biology of the cell, vol. 21, no. 24, pp. 4300-4305,
population, we will observe the HSC function with conditional deletion of Sirt1 in 2010.
pericyte by utilizing LeptinR-Cre.
