Near-infrared light (NIL) promotes a wide range of biological effects including enhancement of energy production, gene expression and prevention of cell death. This is the first report of the in vivo neuroprotective effects of NIL against optic neuropathy induced by mitochondrial complex I inhibition. Subjects were pigmented rats that received single bilateral intravitreal doses of rotenone, a mitochondrial complex I inhibitor, or rotenone plus one of three different doses of NIL. Treatment effects were evaluated at behavioral, structural and neurochemical levels. Rotenone induced a decrease in visual function, as determined by changes in the dark-adapted illuminance sensitivity threshold, escape latency and rate of successful trials in a two-choice visual task, compared with vehicle-treated controls. Behavioral impairment correlated with a decrease in retinal and visual pathway metabolic activity, retinal nerve fiber layer thickness and ganglion cell layer cell density. These changes were prevented by NIL treatments in a dose-dependent manner. Whole-brain cytochrome oxidase and superoxide dismutase activities were also increased in NIL-treated subjects in a dose-dependent manner, suggesting an in vivo transcranial effect of NIL. In whole-brain membrane isolates, NIL prevented the rotenone-induced decrease in cell respiration. The results show that NIL treatment can effectively prevent the neurotoxic effects of rotenone and that it might be used in the treatment of neurodegenerative disorders associated with mitochondrial dysfunction.

Wii-based IVG may be offered as an effective supplement to conventional therapy in the rehabilitation of children with CP.

Methylene blue (MB) is a diaminophenothiazine with potent antioxidant and unique redox properties that prevent morphologic degenerative changes in the mouse retina induced by rotenone, a specific mitochondrial complex I inhibitor. This study evaluated pigmented rats to determine whether MB's neuroprotective effects against rotenone-mediated retinal neurotoxicity have functional relevance and whether these effects are mediated by an improvement in neuronal energy metabolism in vivo. Visual function was behaviorally assessed by determining differences in the illuminance sensitivity threshold pre- and post-bilateral intravitreal injection of rotenone (200 microg/kg) or rotenone plus MB (70 microg/kg). Retinal degeneration was morphologically studied using unbiased stereological tools. Changes in histochemically determined cytochrome oxidase activity in the visual pathway were used to evaluate the impact of treatments on neuronal energy metabolism. Rotenone induced a 1.4 log unit increase in the illumination threshold compared to baseline, as well as a 32% decrease in ganglion cell layer cell (GCL) density, and a 56% decrease in GCL layer + nerve fiber layer thickness. Co-administration of MB prevented the changes in visual function and the retinal histopathology. Furthermore, rotenone induced a functional deafferentation of the visual system, as revealed by decreases in the metabolic activity of the retina, superior colliculus, and visual cortex. These metabolic changes were also prevented by MB. The results provided the first demonstration of MB's behavioral and metabolic neuroprotection against optic neuropathy, and implicate MB as a candidate neuroprotective agent with metabolic-enhancing properties that may be used in the treatment of neurodegenerative diseases associated with mitochondrial dysfunction.

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