Efeito do laser de baixa potência em mecanismos de reparo de membrana e biogênese de corpúsculos lipídicos em células musculares: papel na infecção por Trypanosoma cruziin vitro

Abstract

Plasma membrane (PM) is a structure susceptible to damage and due to this presents an efficient membrane repair mechanism (MR), essential for cell survival.One of the repair mechanisms is endocytosis of damage and sealing of the PM mediated by calcium influx.By subverting the repair machinery by triggering PM injuries, protozoa such as Trypanosoma cruzi can more easily enter cells using endocytic vesicles formed during activation of these processes.T. cruzi is also capable of manipulating the biogenesis of lipid bodies (LBs), biologically active organelles present in the eukaryotic cell cytoplasm.Additionally, low level laser therapy (LLL) consists of the application of a coherent, collimated and monochromatic beam of light with low energy values as a method of enhancing the regeneration and regulation of functional disorders. Knowing the importance of MR and LBs for cellular responses and during infection, the objective of this study was to investigate the effect of LLL on the mechanism of MR and LBs biogenesis in theabsence or not of cellular infection by T. cruzi.Undifferentiated (myoblasts) and differentiated (myotubes) muscle cells of the C2C12 strain infected with the T. cruzi DM28c strain were irradiated with LLL, at 808 nm wavelength, 100 mW output power, 30 J / cm2 dose, for 8 seconds, continuous light-emitting mode, spot-time in a single session. Afterwards the cultures were infected with T. cruzi and sent for microscopy, Western Blot and ELISA analysis.Our results demonstrated that LLL irradiation induced increased calcium-dependent MR activation in myoblasts and myotubes. As expected, T. cruzi infection increased the formation of LBs. However, in previously irradiated myotubes there was a decrease in these organelles. LLL generated an increase in LBsbiogenesis in uninfected cells. The irradiation was also able to modulate inflammatory mediators by decreasing IL-6, IL-10 and TNF-α levels in infected muscle cells.Thus, our results demonstrated the capacity of LLL modulation in the MR mechanism, in the biogenesis of LBs and inflammatory mediators in a T. cruzi infection model, suggesting a role of LLL in PM permeabilization, cellular lipid metabolism and immune response.