Splicing factor-modulated generation of mechano growth factor regulates physiological processes in osteoblasts under mechanical stimuli

ABSTRACT Mechanical stimuli influence various physiological processes in osteoblasts. We previously showed that mechano-growth factor (MGF), a splicing variant of insulin-like growth factor 1, is highly expressed in osteoblasts in response to mechanical stimuli. This study aims to explore the systemic functions of MGF in osteoblasts, and the mechanisms by which mechanical stress regulates the alternative splicing of Igf1 to generate MGF. We found that MGF promoted the proliferation and migration of osteoblasts, while it inhibited their differentiation via Erk1/2 pathway. Furthermore, cyclic stretching upregulated the expression of ASF/SF2, which in turn regulated the expression of MGF. Our findings indicate that mechanical stimuli influence the physiological responses of osteoblasts by increasing the expression of MGF, which is regulated by splicing factors.