Low-level laser irradiation protects the chick embryo chorioallantoic membrane from UV cytotoxicity

• Published in: Archives of biological sciences Vol. 70; no. 1; pp. 119 - 127
• Main Authors: Hammami, Amira, Amri, Mohamed, Mokni, Meherzia
• Format: Journal Article
• Language: English
• Published: University of Belgrade, University of Novi Sad 2018
• Subjects: chorioallantoic membrane; cytotoxicity; low level laser irradiation; UV irradiation; vascular protection
• ISSN: 0354-4664; 1821-4339
• DOI: 10.2298/ABS170706031H

Low-level laser therapy or photobiomodulation is the medical use of a very low intensity light in the red to near infrared (wavelengths in the range of 630-940 nm). The present work was conducted to explore the effects of both UV and low-level laser irradiation (LLLI) on microcirculation using the in vivo model of the chick embryo chorioallantoic membrane (CAM). The effects were assessed by measuring lipid peroxidation and antioxidant enzyme activity. Cell cytotoxicity, survival and intracellular reactive oxygen species (ROS) of the CAM were also evaluated. We found that UV irradiation induced alterations of the vessels, leading to bleeding and extravasation. This effect was intensified after 60 min of exposure to UV irradiation, leading to marked edema. UVA irradiation increased cell cytotoxicity as assessed by lactate dehydrogenase (LDH) release (56.23% of control) and reduced cell viability as assessed by decreased fluorescein diacetate (FDA) fluorescence (56.23% of control). Pretreatment with LLLI prior to UV exposure protected the CAM tissue from UV-mediated cell death. This protective effect was supported by the observation of significantly inhibited lipid peroxidation (from 0.3±0.004 for UV, to 0.177±0.012 after LLLI pretreatment), ROS and O2 -production, as indicated by respective dihydrorhodamine (DHR) and dihydroethidium (DHE) intensities (from 132.78% of control for UVA, to 95.90% of control for L-UV (DHR), and from 127.34% of control for UVA, to 82.03% of control for L-UV (DHE)), and by preventing the increase in oxidative activities. LLLI efficiently protected CAM cells from UV-induced oxidative stress and appeared as a safe protective pretreatment against UV irradiation.