Caffeine, Exercise Stimulate Death of Sun-Damaged Cells
Mouse study shows caffeine plus exercise stimulates apoptosis more than either alone
TUESDAY, July 31 (HealthDay News) -- Caffeine plus exercise synergistically stimulates the death of epithelial cells in mice that have sunburn-like damage due to ultraviolet light, according to a report published July 30 in the Proceedings of the National Academy of Sciences. More study is needed to determine if the combination has an effect on human actinic keratoses or squamous cell carcinomas, the authors said.
Allan Conney, Ph.D., of Rutgers, the State University of New Jersey, and colleagues treated SKH-1 mice with caffeine in the drinking water (either 0.1 or 0.4 mg/ml), voluntary running wheel exercise, or caffeine plus exercise, for two weeks.
Mice treated with low-dose caffeine, exercise, or both exhibited no variation in body weight or food intake but did have a reduction in parametrial fat pads and the dermal fat layer. There was also an increase in the number of UVB-induced apoptotic sunburn cells by 96 percent, 120 percent, and 376 percent, respectively, and the number of UVB-induced activated caspase 3-positive cells by 92 percent, 120 percent, and 389 percent. The high dose of caffeine plus exercise was less effective than was the low dose of caffeine.
"These results suggest a need for further studies to determine the effects of combinations of voluntary exercise and orally administered low-dose levels of caffeine on UVB-induced carcinogenesis in animal models as well as studies to determine the effects of caffeine or caffeine-containing beverages in combination with exercise on the formation of sunlight-induced actinic keratoses and squamous cell carcinomas in humans," the authors wrote.