nd injected Tβ4 twice per week for six months. The current study adopted an acute ischemic model and daily injected Tβ4 for four weeks. The different pathophysiological condition of skeletal muscle may have a different response to Tβ4. A much higher dose of Tβ4 was used in Spurney’s study also. This may stimulate the fusion of skeletal muscle progenitor cells, which in turn contributes to the muscle regeneration.

In summary, the current study demonstrates that Tβ4 stimulates angiogenesis and increased skeletal muscle progenitor cell density, but failed to increase regenerating muscle fiber in ischemic limb muscle. Further study should be performed to investigate the underlying mechanism that the role of Tβ4 on homing and migrating of Pax3/7+ muscle progenitor cells has.

5. ACKNOWLEDGEMENTS

The project was funded by Singapore National Medical Research Council (NMRC) grant EDG09may058.

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