The Effects Of Bortezomib On C2C12 And Its Mechanism

Objective: The study was aimed to investigate bortezomib’s effects on the growth and differentiation of a mouse myoblast line C2C12 and explored the signaling pathways involved.Methods:(1) The C2C12 myoblasts were cultured in high glucose-containing DMEM complemented with 2% horse serum to induce differentiation,then stained using giemsa and observed under microscope;(2) Differentiation of bortezomib on C2C12 cell was stained by giemsa and observed under microscope;(3)Viability of bortezomib on C2C12 cell was determined by MTT assay;(4)Apoptosis and cell cycle of bortezomib on C2C12 cwere tested by flow cytometry;(5) The mechanism of bortezomib on C2C12 differentiation 、apoptosis and cell cycle were assessed by western blot and immunofluorescence.Results: Data showed that bortezomib inhibited formation of multinucleated myotubes. The inhibition of myotube formation was accompanied by decreased expression of Myogenin.C2C12 cells exhibited a dose-dependent decrease in cell viability in response to increasing concentrations of bortezomib.Annexin V/PI analysis showed a significant increase in apoptosis after exposing the cells to bortezomib for 24 h,the detection of cleaved caspase-3 further confirmed apoptosis. The apoptosis induced by bortezomib was associated with reduced expression of p-ERK. Cell cycle analysis revealed that C2C12 cells underwent G2/M cell cycle arrest when incubated with bortezomib for 24 h.Conclusion:Data suggest that bortezomib can inhibit differentiation of C2C12 cell,inhibit cell viability,induce cell death and undergo G2/M cell cycle arrest at clinically relevant doses.Research on the cellular level is not supported by clinical bortezomib on bortezomib for the treatment of skeletal muscle atrophy.