Polychromatic LED in oval full-thickness wound healing in non-diabetic and diabetic rats

Our goal was to determine the efficacy of polychromatic light-emitting diode (LED) in the enhancement of wound healing in non-diabetic and diabetic rats.

LEDs are increasingly used as an alternative light source for phototherapy.

A cluster of 25 LED photons at 510-543, 594-599, 626-639, 640-670, and 842-872 nm wavelengths with 272-mW output power was used. Male Sprague-Dawley rats (n = 61) were randomly assigned into non-diabetic and diabetic groups and into light treatment groups, that is, control, 5, 10, 20, and 30 J/cm(2). Streptozotocin was used for diabetes induction. Wounds were created using a scalpel after 1 week of wounding. Wounds were measured daily and plotted in time, and the trendline was fitted to obtain slope values. Relative wound healing percentage was computed as follows: RWH% = [(Slope treated - Slope control)/(Slope control)] x 100. The t-test (alpha = 0.05) was used for analysis.

The RWH% in the non-diabetic rats was insignificant (p > 0.05) at 5, 10, 20, and 30 J/cm(2) treatments, giving 4.3 +/- 1.97%, 5.4 +/- 1.94%, 4.5 +/- 1.96%, and 1.2 +/- 2.03%, respectively. The healing of diabetic rats was significantly impaired by -11.7 +/- 3.25% (p = 0.02), which was mitigated by 5 J/cm(2) treatment (2.4 +/- 3.02%, (p) = 0.40) and 10 J/cm(2) treatment (-5.5 +/- 3.28%, p = 0.11). Diabetic wound healing using 20 J/cm(2) (-8.7 +/- 3.39%, p = 0.03) and 30 J/cm(2) (-10.90 +/- 1.97%, p = 0.01) affected significant inhibition.

The effect of polychromatic LED therapy in oval full-thickness wound-healing in the diabetic model with the use of 5 and 10 J/cm(2) is promising. Further studies to determine optimum dosimetry and efficacy of LEDs are recommended.