Low-level Laser Therapy Promotes Vascular Endothelial Growth Factor Receptor-1 Expression in Endothelial and Nonendothelial Cells of Mice Gastrocnemius Exposed to Snake Venom

作者：Dourado Doroty M; Favero Silvio; Matias Rosemary; Carvalho Paulo de Tarso C; da Cruz Hoefling Maria Alice^*

来源：Photochemistry and Photobiology, 2011, 87(2): 418-426.

DOI：10.1111/j.1751-1097.2010.00878.x

Crotalinae snake venoms cause severe local myonecrosis and microvasculature failure at the bite site. We evaluated whether low-level laser therapy (LLLT) could accelerate angiogenesis and myoregeneration in male Swiss mice injected with Bothrops moojeni venom through immunohistochemistry of the vascular endothelial growth factor receptor-1 (VEGFR-1). Envenomed gastrocnemius was either unirradiated (V) or irradiated with HeNe (VHN, 632.8 nm) or GaAs (VGA, 904 nm, 10000 Hz). Animals sacrificed at 3 and 12 h were irradiated once (4 J cm-2), at 24 h (twice) and at 3, 7, 21 days (4, 8, 22 times, respectively). At 3 days, LLLT increased angiogenesis (80%:HeNe vs 40%:GaAs), decreased neutrophils and increased proliferation of regenerating cells. However, after 21 days, myoregeneration observed in the VHN group appeared delayed compared with the V group. As LLLT improved revascularization, the suggestive delay in myoregeneration could be a dose-response inhibitory effect caused by multiple irradiations in myogenesis. The immunodetection of VEGFR-1 in neutrophils, macrophages, satellite cells, fibroblasts, Schwann cells and skeletal and smooth muscle fibers (not seen in saline-controls) at only the acute stages of envenoming suggests a mediator role for VEGFR-1 in local alterations. This is the first time that VEGFR-1 expression, and its modulation by photostimulation, has been demonstrated in endothelial and nonendothelial cells of snake envenomed skeletal muscle.

• 出版日期2011-4