Low-level lasers affect uncoupling protein gene expression in skin and skeletal muscle tissues

Abstract

Wavelength, frequency, power, fluence, and emission mode determine the photophysical, photochemical, and photobiological responses of biological tissues to low-level lasers. Free radicals are involved in these responses acting as second messengers in intracellular signaling processes. Irradiated cells present defenses against these chemical species to avoid unwanted effects, such as uncoupling proteins (UCPs), which are part of protective mechanisms and minimize the effects of free radical generation in mitochondria. In this work UCP2 and UCP3 mRNA gene relative expression in the skin and skeletal muscle tissues of Wistar rats exposed to low-level red and infrared lasers was evaluated. Samples of the skin and skeletal muscle tissue of Wistar rats exposed to low-level red and infrared lasers were withdrawn for total RNA extraction, cDNA synthesis, and the evaluation of gene expression by quantitative polymerase chain reaction. UCP2 and UCP3 mRNA expression was differently altered in skin and skeletal muscle tissues exposed to lasers in a wavelength-dependent effect, with the UCP3 mRNA expression dose-dependent. Alteration on UCP gene expression could be part of the biostimulation effect and is necessary to make cells exposed to red and infrared low-level lasers more resistant or capable of adapting in damaged tissues or diseases.

Low-level lasers on microRNA and uncoupling protein 2 mRNA levels in human breast cancer cells

“…UCP2 mRNA plays a key role as a sensor of mitochondrial oxidative stress [29], protecting cells against overproduction of mitochondrial reactive oxygen species [30]. In this aspect, our findings agree that reactive oxygen species are involved in laser-induced effects [31] and reinforce that low-level lasers increase the UCP2 mRNA levels to protect cells against oxidative damage [26].…”

“…On the other hand, studies have demonstrated that increased mir-15a levels decrease UCP2 mRNA levels [20]. Previous results demonstrated that exposure to low-level lasers increases UCP2 mRNA levels in skin and skeletal muscle tissue from Wistar rats [26]. However, despite no alteration of mir-15a levels, our findings show that MDA-MB-231 cells exposed to a lowlevel red laser (figure 3) present increased UCP2 mRNA levels at the lower fluence (25 J cm −2 ) and low-level infrared laser exposure increases UCP2 mRNA levels in these cells at the higher fluence (50 J cm −2 ) (figure 6).…”

Low-level lasers alter mRNA levels from traditional reference genes used in breast cancer cells

“…Low-level red and infrared lasers, into the so-called therapeutic window (600 up to 1100 nm), are able to induce molecular effects, which are used in clinical protocols for the treatment of a number of diseases in phototherapy [25,26] and photodynamic therapy [27][28][29]. As these molecular effects are not yet understood, mainly gene expression, RT-qPCR has been used to evaluate laser-induced effects on mRNA levels [30,31]. However, an adequate reference gene is necessary when taking into account the biostimulation (or biomodulation) effect induced by exposure to low-level lasers [12].…”

Introducing theLaser PhysicsandLaser Physics Lettershighlights of 2016

“…tissues-UCP2 and UCP3 (uncoupling protein) mRNA gene relative expression in the skin and skeletal muscle tissues of Wistar rats exposed to low-level red and infrared lasers is evaluated [37]. • Biospeckle technique for the non-destructive differentiation of bruised and fresh regions of an Indian apple using intensity-based algorithms-in a rigorous comparison, a number of algorithms are applied to differentiate the bruised and fresh regions of an Indian apple through biospeckle technique during its 9 day shelf life [38].…”