Treatment Study of Carnosine Versus Placebo in Gulf War Illness (GWI)

Background: Homocarnosine (beta-alanine - gamma-aminobutyric acid) is one of the most abundant dipeptides in the brain. It has important antioxidant properties. Both beta-alanine and GABA are neurotransmitters, suggesting that cleavage of this dipeptide by carnosine dipeptidase 1 (CNDP1) may have important regulatory functions in vivo. Drug: Homocarnosine is not available. Carnosine (beta-alanine - histidine) is an over-the-counter dietary supplement that shares the antioxidant properties. We proposed that oral carnosine would be absorbed from the gut, cross the blood brain barrier, reduce presumed brain oxidant stress that participated in illness pathology, and improve subject health. Hypothesis: Carnosine supplementation for 12 weeks by mouth in Gulf War Illness subjects would improve cognitive and other outcomes compared to placebo treatment. Subjects: Gulf War Illness subjects met 1996 Fukuda criteria for Chronic Multisymptom Illness. Design: Pilot study. Double blind randomized placebo controlled with comparisons between Week 0 (Baseline, pre-randomization) and Week 12 (end of study) Outcomes: This pilot study included included cognitive testing, magnetic resonance imaging during the 2-back working memory task, self-report of psychometric and other subjective symptoms, tenderness testing by dolormetry, and pain threshold to assess reproducibility in the placebo-treated subjects, and potential treatment effects in the active study drug subjects. The study and each of the outcomes at weeks 0 and 12 are described in detail in the final published paper and in its extensive supplementary on-line materials (Baraniuk JN et al. Glob J Health Sci. 2013 5:69-81. PMID:23618477 PMCID:PMC4209301). An improvement on accuracy on the 2-back working memory task between 0 and 12 weeks was the primary outcome. Other evaluations were secondary outcomes.