Effect of products secreted by laser irradiated macrophages on myoblasts

Abstract

Low-level laser therapy (LLLT) has been widely used in clinical practice to accelerate the repair of muscle tissue, but little is known regarding its effect on macrophages. Macrophages play a major role in inflammation and repair processes. The aim of the present study is to analyze the effects of products secreted by activated and irradiated macrophages on the viability and proliferation of myoblast cells. A further aim is to determine the macrophage production of nitric oxide. Macrophages of the J774 line will be activated to simulate an inflammatory situation and will receive two different laser irradiation parameters (780 nm, 70 mW, 3 J/cm2 and 660 nm, 15 mW, 7.5 J/cm2). The methodology will consist of viability and proliferation assays (MTT) of myoblast C2C12 cultures treated with macrophage culture supernatants and the determination of nitric oxide content in these supernatants. In each experimental situation, non-irradiated cells will serve as controls. Three independent experiments will be performed under each condition and the results will be statistically analyzed.(AU)