ABSTRACT
Low-level laser (or light) therapy (LLLT), also called phototherapy or
photobiomodulation, refers to the use of photons to alter biological
activity. Basically, lightwithin a certain range ofwavelengths (optical
window) is able to effectively excite tissue chromophores such as
cytochrome c oxidase (possessing high absorption bands in the red
and near-infrared spectral regions where light can penetrate deeply
into tissue), thus bringing about a myriad of cellular events (Ham-
blin and Demidova, 2006). The most widely accepted mechanism
of action of LLLT is through the activation of mitochondria, where
components of the electron transport chain (ETC) or respiratory
chain serve as chromophores and, thus, as targets for the action of
LLLT (Hamblin and Demidova, 2006). Mitochondrial activation, in
turn, stimulates ATP production, causes release of nitric oxide, and
induces reactive oxygen species, which together further result in the
stimulation of redox-sensitive transcription factors and expression
of gene products. Thus, LLLT results in processes such as tissue
repair, wound healing, prevention of cell death, and other long-
term effects (Hamblin and Demidova, 2006). Non-thermal, coherent
light sources (lasers) or non-coherent light sources consisting of
filtered lamps or light-emitting diodes (LEDs) are used in this type
of therapy for reducing pain and inflammation, augmenting tissue
repair and regeneration, deeper tissues and nerves, and preventing
tissue damage (Chung et al., 2012; Gupta et al., 2012). In the last few
decades, non-ablative laser therapies have been used increasingly in
dermatology for the aesthetic treatment of fine wrinkles, photoaged
skin and scars, a process known as photorejuvenation.More recently
they have also been used for treating inflammatory acne (Seaton
et al., 2006). Their potential use for other dermatological conditions
and cosmetic indications such as vitiligo, psoriasis, photoprotection,
hair regrowth, and fat reduction has been shown by several
studies. In this chapter, we will briefly discuss these cosmetic and
dermatological applications of LLLT, starting with its current and
potential use in cosmetic dermatology and various skin conditions,
hair loss treatment, and finally in fat reduction procedures and
cellulite treatment.
