Schwartz et al149 observed that core temperature minima were lower during the extended photoperiod of summer compared with winter in SAD patients, but not controls. In studying the oscillations of facial skin and core temperatures in relation to slowwave activity during sleep, Schwartz et al150 found that brain cooling activity, which oscillates

in an ultra dian manner during sleep, is reduced during winter depression, providing support for the hypothesis that brain temperatures are elevated during winter depression. Functional anatomic and retinal sensitivity factors Seggic et al151 observed that antidepressant medication (sinuequan) reversed the increased sensitivity Inhibitors,research,lifescience,medical to light in depression. Terman and Terman152 reported heightened retinal sensitivity Inhibitors,research,lifescience,medical with increased light exposure and supersensitivity of SAD patients relative to controls in winter. LJVA-spectrum light did not increase the antidepressant response153 and illumination applied in the upper visual field was most effective.154 An increase in cerebral blood flow is associated with recovery Inhibitors,research,lifescience,medical following light treatment for SAD.155 Other Patients with non-SAD major Apoptosis Compound Library depression show a more

pronounced light-associated increment of parasympathetically controlled cardiac functions compared with other depressed patients and controls.156 Light therapy normalizes transducin (G1 protein) levels observed to be reduced in winter depression.157 No effects of light therapy were noted on basal glucagon levels Inhibitors,research,lifescience,medical in SAD and comparison subjects.158 Immune-inflammatory markers are increased in SAD patients but are not altered by successful light therapy.159 In summary, the proposed mechanisms for light treatment primarily involve effects on the circadian timing system, melatonin, serotonin, and temperature regulation. Conclusions Light treatment is efficacious for SAD (winter-type) and an increasing

database suggests that it has beneficial effects in nonseasonal depression as Inhibitors,research,lifescience,medical well. In toto, bright light (>2500 lux) results in greater improvement than dim light; morning light of at least 3 to 4 days duration results in more responders than evening light in SAD; UV-spectrum wavelengths are not required for antidepressant effects; and dawn-stimulation is an effective alternative. Light visors, in contrast, are not efficacious. Carbohydrate craving is Oxalosuccinic acid a predictor of response and there are minimal side effects with the exception of the risk of inducing mania in bipolar patients. Further investigation is warranted with respect to light treatment’s mechanism of action.
Multiple neurochemical pathways are involved in the pathology of Alzheimer’s disease (AD). The following factors have been implicated in the development of AD: P-amyloid; tau proteins; apolipoprotein E (APOE); degeneration of cholinergic, serotonergic, and dopaminergic neurons; oxidative damage; inflammation; estrogen deficiency; and glutamatergic neurotransmission.