Alzheimer's disease (AD) is a devastating neurodegenerative condition associated with severe cognitive and behavioral impairments. Circadian rhythms are recurring cycles that display periods of approximately 24 hours and are driven by an endogenous circadian timekeeping system centered on the suprachiasmatic nucleus of the hypothalamus. We review the compelling evidence that circadian rhythms are significantly disturbed in AD and that such disturbance is of significant clinical importance in terms of behavioral symptoms. We also detail findings from neuropathological studies of brain areas associated with the circadian system in postmortem studies, the use of animal models of AD in the investigation of circadian processes, and the evidence that chronotherapeutic approaches aimed at bolstering weakened circadian rhythms in AD produce beneficial outcomes. We argue that further investigation in such areas is warranted and highlight areas for future research that might prove fruitful in ultimately providing new treatment options for this most serious and intractable of conditions.

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The hallmarks of acute lung injury (ALI) are the compromised alveolar-capillary barrier and the extravasation of leukocytes into the alveolar space. Given the fact that the peroxisome proliferator-activated receptor-γ agonist rosiglitazone holds significant anti-inflammatory properties, we aimed to evaluate whether rosiglitazone could dampen these hallmarks of local pulmonary inflammation in a porcine model of lung injury. For this purpose, we used a model of lipopolysaccharide (LPS, 50 μg/kg)-induced ALI. One hundred twenty minutes following the infusion of LPS, we started the exposure to rosiglitazone through inhalation or infusion. We found that intravenous rosiglitazone significantly controlled local pulmonary inflammation as determined through the expression of cytokines within the alveolar compartment. Furthermore, we found a significant reduction of the protein concentration and neutrophil activity within the alveolar space. In summary, we therefore conclude that the treatment with rosiglitazone might dampen local pulmonary inflammation during the initial stages of ALI.