670 nm photobiomodulation improves the mitochondrial redox state of diabetic wounds.

PubMed ID: 33392015

Author(s): Mehrvar S, Mostaghimi S, Foomani FH, Abroe B, Eells JT, Gopalakrishnan S, Ranji M. 670 nm photobiomodulation improves the mitochondrial redox state of diabetic wounds. Quant Imaging Med Surg. 2021 Jan;11(1):107-118. doi: 10.21037/qims-20-522. PMID 33392015

Journal: Quantitative Imaging In Medicine And Surgery, Volume 11, Issue 1, Jan 2021

BACKGROUND Photobiomodulation (PBM) by far-red (FR) to near-infrared (NIR) light has been demonstrated to accelerate diabetic wound healing in preclinical and clinical studies. Mitochondrial dysfunction and oxidative stress play key roles in impaired diabetic wound healing, and the effect of PBM on the metabolic state of diabetic wounds remains to be elucidated.

METHODS In this study, a custom-designed in vivo fluorescence imaging technique was used to quantitatively assess the effect of FR-PBM on the mitochondrial bioenergetics of diabetic wounds. The intrinsic fluorescence of two mitochondrial co-enzymes, nicotinamide adenine dinucleotide (NADH) and oxidized flavin adenine dinucleotide (FAD), was monitored to quantify the redox ratio (RR) (NADH/FAD) of wounds over time.

RESULTS Using an excisional model of wound healing, we demonstrated that 670 nm (FR) PBM improved mitochondrial bioenergetics and stimulated the rate of wound healing in diabetic db/db mice. Wound closure and the RR of diabetic wounds in response to 670 nm PBM (4.5 J/cm2, 60 mW/cm2 for 90 s per day, 5 days/week) were compared to the sham-treated group. At day 9 of post-wounding, we observed a 43% decrease in the wound area and a 75% increase in RR in FR-treated diabetic mice compared to sham-treated diabetic mice.

CONCLUSIONS We conclude that the increase in mitochondrial RR and the related decrease in oxidative stress may be an important factor in FR-PBM mediated acceleration of wound healing in diabetic mice.

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