The effects of probiotic supplementation and eating a high fat diet on sensitivity of rats to the behavioral effects of methamphetamine

Abstract

Eating a high fat diet can lead to obesity, insulin resistance, and can cause dysfunction to dopamine systems. For example, rats eating high fat laboratory chow are more sensitive than rats eating standard chow to the behavioral effects of drugs that act on dopamine systems (i.e., methamphetamine). Dietary supplementation with probiotics (including a combination of lactobacillus and bifidobacterium) has been shown to aid in digestion and decrease depressive‐like behavior among rats eating high fat chow. It is not known if probiotic supplementation can similarly decrease the effects of eating high fat chow on sensitivity of rats to the behavioral effects of dopaminergic drugs. To test the hypothesis that dietary supplementation with probiotics prevents high fat diet‐induced enhanced sensitivity to methamphetamine, rats eating standard chow (17% kcal from fat), high fat chow (60% kcal from fat), or eating standard or high fat chow with daily probiotic (1 billion CFU) supplementation were tested once weekly using cumulative doses of methamphetamine (0.1–3.2 mg/kg; i.p.) Dose‐response curves were analyzed using two‐way repeated measures ANOVAs using Tukey’s multiple post‐hoc comparisons tests where appropriate. After 5 weeks of testing, there were no significant differences in drug sensitivity to methamphetamine among rats eating different diets. Although the experiment is ongoing, previous literature suggests that sensitivity to methamphetamine will increase with continued testing (e.g., sensitization) and that rats eating high fat chow will be more sensitive to this effect than rats eating standard chow to drugs that act on dopamine systems.Support or Funding InformationO.S. is supported by the National Institute of General Medical Sciences of the National Institutes of Health (NIH) under R25GM069621. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.