Muscle satellite cells (mSCs) isolated from wild-type (WT) or diabetic (db/db) mice and cultured in routine culture conditions (second and fourth day of cell culture, growth medium (GM)) and during differentiation (fourth day of differentiation, differentiation medium (DM)). (A) Morphology of mSCs cultured for 2 or 4 days in GM or for 4 days in DM; representative photos, magnification 100×. (B) Expression of Myf5, CXCR4, Pax7, Mef2, myoD and myogenin mRNAs in subconfluent mSCs isolated from WT and db/db mice and cultured in GM; quantitative RT-PCR (n = 5 to 13). (C) Expression of myoD and myogenin mRNAs in mSCs cultured for 5 days in GM or DM; quantitative RT-PCR (n = 2). EF2 served as an internal control. Each bar represents mean + SEM. *P < 0.05, **P < 0.01, versus WT; #
P < 0.05, versus cells cultured in GM. myoD, myogenic differentiation antigen.