Shining light on nanotechnology to help repair and regeneration

Abstract

Phototherapy can be used in two completely different but complementary therapeutic applications. While low level laser (or light) therapy (LLLT) uses red or near-infrared light alone to reduce inflammation, pain and stimulate tissue repair and regeneration, photodynamic therapy (PDT) uses the combination of light plus non-toxic dyes (called photosensitizers) to produce reactive oxygen species that can kill infectious microorganisms and cancer cells or destroy unwanted tissue (neo-vascularization in the choroid, atherosclerotic plaques in the arteries). The recent development of nanotechnology applied to medicine (nanomedicine) has opened a new front of advancement in the field of phototherapy and has provided hope for the development of nanoscale drug delivery platforms for effective killing of pathological cells and to promote repair and regeneration. Despite the well-known beneficial effects of phototherapy and nanomaterials in producing the killing of unwanted cells and promoting repair and regeneration, there are few reports that combine all three elements i.e. phototherapy, nanotechnology and, tissue repair and regeneration. However, these areas in all possible binary combinations have been addressed by many workers. The present review aims at highlighting the combined multi-model applications of phototherapy, nanotechnology and, reparative and regeneration medicine and outlines current strategies, future applications and limitations of nanoscale-assisted phototherapy for the management of cancers, microbial infections and other diseases, and to promote tissue repair and regeneration.

Physical Modalities in the Management of Wound(s)

“…It amplifies tissue repair, enhances regeneration of different nerves and tissues, and prevents tissue injury in situations where it is likely to occur [12,13]. …”

“…LLLT is composed of two sources: coherent light and noncoherent light sources (lasers) consisting of filtered lamps or light-emitting diodes (LED) or, on occasion, a combination of both [13,14].…”

Photodynamic therapy of tumors with pyropheophorbide-<em>a</em>-loaded polyethylene glycol&ndash;poly(lactic-<em>co</em>-glycolic acid) nanoparticles

“…27 The liposomal NP formulation of the PS verteporfin, named Visudyne, is used in clinics for the treatment of patients with age-related macular degeneration or subfoveal choroidal neovascularization, 28,29 indicating the promising clinical potential of the NP-based strategy for PS delivery. Among various NP-based delivery systems, one based on the biodegradable copolymer poly(lactic-co-glycolic acid) (PLGA), a US Food and Drug Administration-approved material for human use, has received much attention for its high stability and high drug loading.…”

Light-emitting diode therapy (LEDT) before matches prevents increase in creatine kinase with a light dose response in volleyball players

“…The benefits of low-level laser (light) therapy (LLLT) to treat pain [1,2], tendinopathies [3] and to promote tissue healing [2,4] have been investigated for several years. The mechanism of the light-tissue interaction is thought to involve cytochrome c oxidase (Cox) as the main chromophore in the cells able to absorb specific wavelengths of light [5][6][7][8][9].…”