The influence of low intensity laser irradiation on dermal fibroblasts and its role in diabetic wound healing

Fibroblasts are cells found in the connective tissue and are concerned with tissue maintenance where they sustain structural integrity. They form part of and synthesise the extracellular matrix (ECM) and play a key role in wound healing. Diabetes Mellitus (DM) is a group of metabolic diseases which is characterised by the increase of glucose in the blood. The cause may be due to the lack of production of insulin, the hormone responsible for cellular glucose uptake, or insulin resistance. DM puts patients at risk for a variety of long-term complications, including vascular disease, neuropathy and nephropathy. Together, neuropathy and vascular complications in the lower limbs put patients at jeopardy for developing foot ulcers, a condition which often becomes chronic and necessitates amputation. Low intensity laser irradiation (LILI), otherwise known as phototherapy or photobiostimulation, is a form of light therapy which makes use of low powered lasers or light emitting diodes (LEDs) to stimulate biological processes. Chromophores within the cells absorb the photon energy which leads to a series of chemical reactions which drive cellular metabolism. LILI has expressly been shown to accelerate wound healing, even in conditions such as diabetes. Laser irradiation has been shown to accelerate fibroblast function in a number of stressed conditions; it has been shown to hasten fibroblast migration, increases their proliferation, stimulates the release of nitric oxide (NO) and collagen production, and decreases the release of pro-inflammatory cytokines. This chapter will look at the effect of LILI on fibroblasts, particularly in diabetic wound heaing.