Effects of specific inhibitors and low irradiance visible light on the redox cycling of cytochrome c in isolated mitochondria using resonance Raman spectroscopy

摘要

Photobiomodulation (PBM), once known as low level laser therapy (LLLT), is a technique that uses light in the red andnear infrared (NIR) range (600-900 nm) to elicit a beneficial physiological change in tissue. These physiological changesare thought to originate in the mitochondria by altering the metabolic rate for the electron transport chain (ETC). ResonanceRaman spectroscopy at 532 nm was used to determine the reduction/oxidation (redox) state of cytochrome c in isolatedmitochondria after exposure to low irradiance visible light. Mitochondria from porcine heart tissue were isolated andplaced in a succinate buffer and then exposed to NIR (808 nm) light. Some enzymes involved in the ETC were selectivelyindividually blocked and the resonance Raman spectra of cytochrome c redox state was measured before and after beingilluminated by light representing photobiomodulation. By combining data on the cytochrome c redox state with the effectsof inhibiting important enzymes, we can see what the impact of each enzyme in the ETC has on the effects we see fromphotobiomodulation. This method provides a better understanding on the underlying effects of photobiomodulation on themitochondria, which can help direct efforts for targeted effects.