(OR02-03-24) Impacts of Cottonseed and Extra Virgin Olive Oil Intake on Plasma Arachidonic Acid and Eicosanoids: A Randomized Controlled Trial

Objectives: Dietary linoleic (LA) acid, an n-6 polyunsaturated fatty acid, is an arachidonic acid (AA) and eicosanoid precursor. Cottonseed oil (CSO) is relatively high in LA ( >50% of fatty acids) and extra virgin olive oil (EVOO) is relatively low in LA ( < 10% of fatty acids). While it has long been posited that a high n-6 to n-3 fatty ratio in the diet favors production of pro-inflammatory eicosanoids, data demonstrating this phenomenon are sparse. The purpose of this investigation was to determine the response of plasma eicosanoids to diets rich in cottonseed versus olive oil.

Methods: We utilized a double-blind, four-armed, randomized, parallel research design to compare the impact of 30 and 60 g/day of CSO and EVOO for 28 days in metabolically healthy men and women (n=47). Participants consumed a diet that was low in fat and consumed two smoothies per day containing their daily dose of CSO or EVOO. Fasting and post-exercise (30 minutes at 75% of VO2max) plasma samples were collected. LCMS analysis used C18 reverse-phase with a water/methanol gradient. Identifications were made using retention time and high-resolution MS/MS against authentic standards. Quantification involved standard addition to serum for maximum accuracy. Habitual diet prior to and during the intervention were assessed using the Dietary History Questionnaire III. Type II ANOVA was performed with adjusted Tukey HSD for pairwise comparison.

Results: The dietary intervention increased (p < 0.05) the n-6: n-3 ratio in High CSO (Pre: 9.0±1.1 to Post: 72.5±32.1) and Low CSO (Pre: 9.8±1.4 to Post: 90.4±32.5) groups. There was a ~0.5-fold decrease (p < 0.05) in the AA intake in all groups. Lipidomic analyses are ongoing. Plasma AA concentration increased (p < 0.01) 1.2-fold in all groups and did not differ by treatment. No changes were measured at baseline from pre- to post-intervention for eicosanoids. Exercise induced a greater (p < 0.05) increase in 13-14 dihydro15ketoPGD2 in the 30 g/day CSO group and 13-14 dihydro15ketoPGE2 in the 60 g/day CSO group.

Conclusions: Consumption of both CSO and EVOO at both 30 and 60 g/day doses superimposed on a low-fat diet increased plasma AA concentrations similarly despite a five-fold difference in dietary LA between CSO and EVOO. However, enhanced exercise-induced increases in two prostaglandins were measured only with CSO supplementation.

Funding Sources: Cotton Incorporated 22-070