Botanical seed
oils reduce the generation of
leukotrienes in patients with
asthma. Our objective was to determine the efficacy of a botanical seed oil combination against airflow obstruction in
asthma, and to determine the pharmacogenomic effect of the
leukotriene C4 synthase (LTC4S) polymorphism A-444C. We conducted a randomized, double-blind, placebo-controlled, cross-over clinical trial in mild to moderate asthmatics to determine the change in FEV1 after 6 weeks of
therapy with borage and echium seed
oils versus
corn oil placebo. We also examined the effect of the variant LTC4S -444C allele on the change in lung function. We did not identify a difference in FEV1 in the study cohort as a whole (n = 28), nor in the group of A homozygotes. In the C allele carriers (n = 9), FEV1 improved by 3%
after treatment with borage and echium seed
oils and declined by 4% after placebo
corn oil (p = 0.02). All 9 C allele carriers demonstrated an improvement in their FEV1 on active treatment compared to placebo as compared to only 7 out of 19 A allele homozygotes (p = 0.007). We observed transient differences in ex vivo
leukotriene generation from circulating basophils and granulocytes. We did not observe significant differences in urinary
LTE4 levels. We conclude that compared to
corn oil, a combination of borage and echium seed
oils improves airflow obstruction in mild to moderate asthmatics who carry the variant allele in the LTC4S gene (A-444C). Botanical oil supplementation may have therapeutic potential in
asthma if used in a personalized manner.
TRIAL REGISTRATION: This trial was registered at http://www.clinicaltrials.gov as NCT00806442.