Low-intensity continuous ultrasound effect on proliferation and morphology of fibroblast cells

Abstract

Recently, the use of ultrasound (US) for triggering drug release to specific tissues was explored, but its direct effects on cells have not been thoroughly understood. For this reason, this study aimed to investigate the impact of US powers and US irradiation times on fibroblast cells (NIH-3T3). The results showed that the diverse US settings had varying effects on cell proliferation and distribution in the polystyrene culture dish. Interestingly, at 10 W, 43 kHz with changing exposed time up to 30 min either stimulated or inhibited fibroblast cell growth after 24 and 72 h of cultivation compared to the control sample in the absence of US, while longer US exposure time led to a moderate reduction in cell quantity. Moreover, higher US levels of 20 and 30 W could cause an aggregation of cells and sublethal damage to the cells. Importantly, the morphology of fibroblast was changed from stellate-shape to round-shape under greater US powers. Elevated US power also influenced interactions between proteins and lipids, affecting the atomic and molecular charges, leading to changes in both zeta potential and pH of the dispensed cell solution.