Possibly related (and clinical work in humans, to boot):

Francisco Gomez-Lima has done some work showing that, in the case of neurons with mitochondrial issues (downregulated cytochrome c oxidase - which means not enough electron donors for the electron transport chain, notably ECTIII) transcranial light through the forehead can help. The notion is that, like here, photons can stand in for electrons (major difference is that electrons have infinitesimal mass, photons have none - but both can carry charge). As I remember, he was using 1005nm, mostly picked to sidestep the absorption band of hemoglobin - apparently the bone of the forehead isn't a problem.

He's also done work using methylene blue as an electron donor stand-in for CCO.

Just did a quick search: study is here.