Consumption of tart cherries modulates cholinergic pathway in high fat diet fed rats

Cognitive injury is associated with obesity. We investigated the controversial involvement of cerebral cholinergic markers in diet-induced obesity rats (DIO) after exposure to a high-fat diet (HFD) compared to the rats fed with a standard diet (CHOW). The effects of tart cherries seeds powder (DS) and seeds powder plus tart cherries juice (DJS) were also explored. Immunochemical and immunohistochemical results showed an upregulation of choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) in obese rats, except for VAChT in the frontal cortex. The acetylcholinesterase (AChE) enzyme and alpha 7 nicotinic acetylcholine receptor (α7nAChR) were downregulated after HFD in the frontal cortex and hippocampus. Tart cherries supplementations enhanced ChAT and VAChT expressions in the brainstem in both DS and DJS groups. Unlike AChE was reduced in the frontal cortex and hippocampus. The juice intake led to increased α7nAChR in the brain areas compared to DIO rats. Based on the positive modulation of acetylcholine synthesizing enzyme and negative regulation of its hydrolyzing enzyme, it is possible to hypothesize that there is an attempt of recovery to increase the acetylcholine content, and the anthocyaninrich tart cherries enhance this mechanism in specific brain areas. These data suggest how the cholinergic markers analyzed can be targeted by this nutritional supplementation. Since the activation of α7nAChR induces neuroprotection resulting from anti-inflammatory effects, tart cherries juice should be proposed within the diet to benefit the brain.