Rapamycin Treatment of Tendon Stem/Progenitor Cells Reduces Cellular Senescence by Upregulating Autophagy

<div>Bleomycin induces PTSC senescence in a dose-dependent manner. (a) Rat PTSCs were treated without or with bleomycin (Bleo) for 5 days. (b) PTSCs were stained for senescence-associated <i>β</i>-galactosidase (<i>β</i>-gal) activity. As seen, at 10 and 50 <i>μ</i>g/ml, the senescent cells look flattened and enlarged (a, yellow arrows) compared to control cells, which are elongated (a, red arrows). <span class="nowrap"><svg height="12.7373pt" id="M16" style="vertical-align:-3.429399pt" version="1.1" viewbox="-0.0498162 -9.3079 99.8059 12.7373" width="99.8059pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M409 504C401 567 396 607 392 642C354 654 312 665 266 665C137 665 60 583 60 487C60 374 161 325 225 290C300 250 355 215 355 141C355 68 311 21 235 21C131 21 86 122 71 183L41 176C48 128 61 42 68 21C78 16 93 8 118 0C142 -7 175 -15 216 -15C349 -15 438 69 438 174C438 287 344 333 265 374C186 414 138 449 138 522C138 576 172 631 249 631C336 631 363 562 380 499L409 504Z"></path></g><g transform="matrix(.013,0,0,-0.013,6.345,0)"><path d="M390 111C344 68 312 56 269 56C212 56 118 102 118 241C118 346 175 401 241 401C277 401 312 388 342 360C350 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(d) Tendon tissues obtained from 2.5 month-old and 18 month-old rats were stained for the <i>β</i>-gal activity. It is evident that the young tendon is well organized without staining of <i>β</i>-gal; in contrast, aged tendon is disorganized and stained with <i>β</i>-gal.</div>

Stem Cells International

fig1

Figure 1

Figure 1: Rapamycin Treatment of Tendon Stem/Progenitor Cells Reduces Cellular Senescence by Upregulating Autophagy 