(P03-016-23) Pharmacokinetics of Tomato Steroidal Alkaloids in Healthy Adults Following Consumption of Two Doses of Tomato Juice

Objectives: Tomato steroidal alkaloids (TSAs) are gaining traction for their potential health benefit, but little is known about their behavior once in the body. The objective of this study is to elucidate the pharmacokinetics, that is to define the bioavailability and metabolism, of TSAs following a single tomato juice containing meal. We hypothesize that TSAs will be absorbed and undergo extensive phase I and phase II metabolism.

Methods: Healthy subjects (n = 11, 6M/5F) participated in a randomized crossover trial where each person consumed 94 g juice (low dose) and 505 g juice (high dose) with a two-week washout period in between doses. Blood samples were collected at 11 time points over 12-hours following test meal consumption, and plasma was isolated to be analyzed using high-performance liquid chromatography mass spectrometry (HPLC-MS). Fragmentation patterns and comparison to authentic standards (where available) were used for compound identification and quantification. Baseline-corrected area under the absorption curve (AUC) was calculated using the trapezoidal rule to estimate the relative exposure of each metabolite in plasma. TSAs in juice were quantified using HPLC-MS/MS. Relative absorption of TSAs from diet were determined by taking the ratio of the aggregate TSAs in plasma to juice.

Results: A significant difference (p < 0.05) was observed in fractional absorption (mean ± SD) between the high (9% ± 5%) and low (5% ± 2%) dose of tomato juice. More than 90% of the quantified TSAs found in plasma have undergone either a phase I or phase II biotransformation in both interventions. It was found that dihydroxytomatidine, a phase I metabolite, was most abundant with an AUC value of 812.20 ± 157.44 nmol*h/L for the high dose and 60.97 ± 7.87 nmol*h/L for the low dose.

Conclusions: This study demonstrates moderate absorption and extensive metabolism of TSAs and reports the first pharmacokinetic data for these phytochemicals. These data provide context for future studies investigating the potential role that these compounds may play in human health.

Funding Sources: Research was funded by The Ohio Agricultural Research and Development Center, Foods for Health Initiative, and both the Graduate Enrichment Fellowship and Lisa and Dan Wampler Endowed Fellowship for Foods and Health Research.