指導老師 ：鄭伯智老師、林宏榮老師 學生：張維真 報告日期： 100.05.08

1. Myocardial Injection With GSK-3β–Overexpressing Bone Marrow–Derived Mesenchymal Stem Cells Attenuates Cardiac Dysfunction After Myocardial InfarctionCirc Res. 2011 Feb 18;108(4):478-89. 指導老師：鄭伯智老師、林宏榮老師 學生：張維真 報告日期：100.05.08

2. Outline Introduction Methods & Results Conclusion

3. Introduction • The myocardium has been regarded as a terminally differentiated organ lacking regenerative potential. Kajstura J, et al. Circ Res. 2010; 107:305–15. • Cardiac progenitor cells localized in niches have the ability to differentiate intocardiomyocytes (CMs), thereby replenishing the CMs lost because of basal turnover. Beltrami AP, et al. Cell. 2003;114:763–76； Bradfute SB, et al. Proc Natl Acad Sci U S A. 2003;100:12313–8

4. The capacity for cardiac regeneration is insufficient to maintain cardiac function when a massive loss of CMs occurs in response to myocardial infarction (MI) and heart failure.

5. Various adult stem cells,including bone marrow– derived cells, endothelial progenitorcells and mesenchymal stem cells (MSCs), have been shown to be capable of differentiation into CMs, supportsurvival of residential CMs, induce angiogenesis, or promoteinfarct healing when introduced into the heart after MI,clearly establishing the proof of concept that cell-based therapy (CBT) has the potential to improve cardiac functionin the post-MI heart.

6. Macshave the ability todifferentiate into various cell types in the heart, and secreteparacrine factorsstimulating the survival of residential CMs, the tissue repair process, and angiogenesis, making MSCs an ideal source for cardiac CBT. Zimmet JM & Hare JM. Basic Res Cardiol. 2005;100:471–81.; Shujia J et al. Cardiovasc Res. 2008;77:525–33.; Zeng L et al. Circulation. 2007;115:1866 –75.

7. CBT with MSCs in post-MI animal models caused only modest or transient functional improvement, possibly because of the rare survival and the very inefficient CM differentiation of MSCs in vivo. Hill JM et al. Circulation. 2003;108:1009 –14. • For example, ex vivo introduction of Akt increased the survival of MSCs and improved cardiac functionof the post-MI heart in mice subjected to CBT. Mangi AA et al. Nat Med. 2003;9:1195–1201

8. Glycogen synthase kinase-3β • Glycogen synthase kinase (GSK)-3βis a serine/threonine kinase that phosphorylates many intracellular substrates, including β-catenin, glycogen synthase, eIF2B, GATA4, myocardin, c-Jun, cyclin D1, and N-Myc, thereby regulating various intracellular functions. Hirotani S et al. 2007;101:1164 –1174.

9. Haq S et al. Proc Natl Acad Sci U S A. 2003;100:4610–4615.

10. Adam Young D et al. Wiley Interdiscip Rev Syst Biol Med. 2010 Dec 31.

11. Aim • To evaluate whether myocardial injection of GSK-3β– overexpressing MSCs (GSK-3β– MSCs) improves survival of the animals and left ventricular (LV) function and attenuates cardiac remodeling in the post-MI heart compared with injection of control MSCs. • To investigate the underlying mechanism through which injection of GSK-3β–MSCs improves the efficiency of CBT.

12. Study Design Lac-Z、GSK-3β transduced 2-3-week-old C57BL/6 mice MSCs were isolated from bone marrow LacZ-overexpressing MSCs GSK-3β-overexpressing MSCs

13. MI Surgery

14. Three-month-old C57BL/6 mice MI Sham Saline 30μL LacZ-MSCs 1.5×105 cells/ 30μL GSK-3β-MSCs 1.5×105 cells/ 30μL after 2、6 and 12 weeks Survival、LVEDD、LVESD、FS％、 （-）dp/dt（mmHg）、EDP（mmHg）

16. Injection of GSK-3β-Overexpressing MSCs prevents cardiac dysfunction after MI

18. Summary Ι • Injection of untreated MSCs alone does not have long-term therapeutic effects, but ex vivo introduction of GSK-3βsignificantly improves the therapeutic effect of CBT with MSCs after MI.

19. GSK-3βOverexpressing MSCs prevents cardiac hypertrophy Remodeling

21. Summary ІІ Injection with GSK-3β–MSCs promotes repair of MI and/or suppresses MI progression, thereby alleviating the cardiac remodeling seen with injection with saline or LacZ-MSCs.

22. The Tet-Off Tetracycline-regulated expression system

23. Stable Expression of GSK-3β in MSCs Improves the Efficiency of CBT for Chronic Myocardial Infarction

25. Summary ІІІ Stable overexpression of GSK-3β in MSCs is beneficial and inhibits cardiac remodeling after MI.

26. GSK-3β Overexpression in MSCs Enhances Survival and CM Differentiation of MSCs In Vivo

28. Injection of GSK-3β-MSCs increases c-Kit and Ki67-positive cells

30. Summary Ⅳ • Injection of GSK-3β–MSC into the MI • mice induces CM differentiation more • efficiently than that of control MSCs.

31. The Therapeutic Benefits of GSK-3β-Overexpressing MSCs Is, in Part, Mediated by Angiogenesis Through Vegfa Production in MSCs

32. Injection of GSK-3 β-MSCs enhances Vegfa expression, which partially mediates their therapeutic benefits

35. Summary Ⅴ • Upregulation of Vefga is partially involved in the improvement of LV function in the GSK-3β– MSC injected MI mice, and that the therapeutic benefit of GSK-3β–MSCs injection is mediated by both Vegfa-dependent and -independent mechanisms.

36. Conclusion Ex vivo genetic reprogramming of MSCs with GSK-3β improves the therapeutic efficiency of MSCs in thepost-MI heart. GSK-3β overexpression in MSCs achieves several therapeutic benefits, most likely by predirectingMSCs to CM differentiation and inducing secretion of paracrinefactors, including Vegfa.

37. Thanks !!

38. Masson’s trichrome stain Introduction • Masson's Trichrome is most useful todifferentiate collagen from other fibres,particularly smooth muscle and elastin. Results • Nuclei- Black • Cytoplasm, muscle and erythrocytes- Red • Collagen- Green

39. Masson Trichrome&H.E.(10x40)