Akt regulates proliferation induced by low-power laser irradiation in COS-7 cells

Low-power laser irradiation (LPLI) has been regarded as playing a significant role in triggering cellular survival and proliferation. However, the mechanism has not been fully understood. In this study, using real-time single-cell analysis, we investigated the activity of Akt and its effects on cell proliferation induced by LPLI in african green monkey SV40-transformed kidney fibroblast cells (COS-7). We utilized a recombinant fluorescence resonance energy transfer (FRET) Akt probe (BKAR) to dynamically detect the activation of Akt after LPLI treatment. Our results show that LPLI induced a gradual and continuous activation of Akt. Moreover, the activation of Akt can be completely abolished by wortmannin, a specific inhibitor of PI3K, suggesting that the activation of Akt caused by LPLI is a PI3K-dependent event. LPLI promotes cell proliferation through Akt activation since the cell viability was significantly inhibited by PI3K inhibitor. We thus conclude that, Akt activation is well involved in LPLI triggered cell proliferation that acts as a time and dose-dependent manner.