ION CHANNEL EXPRESSION IN THE BRAIN AREAS OF HIGH-FAT DIET FED RATS

Obesity is associated with the development of cerebrovasculardiseases promoting cognitive decline. High Body Mass Index hasbeen suggested as a risk factor for Alzheimer’s disease and vas-cular dementia and has been associated with poorer cognitiveperformance in population-based studies. Evidence suggests thattransient receptor potential (TRP) ion channels dysfunction sig-nificantly contributes to the physiopathology of metabolic andneurological disorders. Mutations in genes encoding TRP chan-nels are the cause of several inherited diseases in humans (the so-called ‘TRP channelopathies’) that affect the cardiovascular,renal, skeletal, and nervous systems. This study aimed to evaluatethe effects of a high-fat diet on ion channel expression in thebrain of diet-induced obesity (DIO) rats. DIO rats were studiedafter 17 weeks under a hypercaloric diet. Moreover, groups ofDIO rats were supplemented with tart cherries seeds powder(DS) or seeds powder plus tart cherries juice (DES) to evaluatethe possible protective effects. DIO rats were compared to thecontrol rats with a standard diet (CHOW). To determine the sys-temic effects of high-calorie diet exposure, we examined foodconsumption, fat mass content and fasting glycemia, insulin lev-els, cholesterol, and triglycerides. qRT-PCR, Western blot, andmorphological analysis were performed in the frontal cortex andhippocampus. After 17 weeks of fat diet, rats increased signifi-cantly their body weight in comparison to the CHOW rats. Nodifferences in body weight were observed in DS and DES ratscompared to age-matched DIO rats. In DIO rats TRPC1 andTRPC6 were up-regulated in the hippocampus, while they weredown regulated in the frontal cortex. In the case of TRPM2expression instead, was increased both in the hippocampus and inthe frontal cortex. All these data are confirmed by immunohisto-chemical and Western blot analysis. Supplemented DIO ratsshowing a different modulation on TRPC1, TRPC6, TRPM2, andTRPV1 ion channel expression in the hippocampus and thefrontal cortex, possibly related to the positive effects of antho-cyanins on reactive gliosis. The identification of neurodegenera-tive changes in DIO rats involving the ion channels expressionmay represent the first insight to better characterize the neu-ronal changes occurring in obesity. Further studies are needed toclarify the benefits of tart cherry supplementation on the preven-tion of cerebrovascular alterations