Changes in S100 protein expression in the cerebellum of rats orally exposed to energy drinks

Abstract

The aim of our study was of assess the rate of S100 protein expression in the cerebellum of rats orally exposed to caffeinated energy drinks (CED) during 2 and 4 weeks. Twenty WAG rats were enrolled in the experiment. They were subdivided into three groups. The animals from group 1 and group 2 (n=7 in each) were orally exposed to a caffeinated energy beverage “Black” at a dose of 12 ml per kg of body weight during two and four weeks, respectively. The control group consisted of 6 intact rats obtained drinking water instead of a caffeine-containing energy drink. Cerebellar S100 expression was evaluated immunohistochemically. Against the background CED oral administration during two and four weeks, the density of granule cell layer becomes lower indicating neuronal loss. S100 protein was upregulated in group 1 in the entire cerebellar cortex. Thus, CED oral exposure resulted in the development of cerebellar astrogliosis. Four-week-long CED consumption resulted in S100 downregulation in the molecular and granular layers. Our findings demonstrate the damage to the cerebellum in rats exposed to CEDs with overexpression of S100, followed by a decrease in its expression.