AUTHOR=Herz Corinna , Frei Linda , Tran Hoai T. T. , Claßen Sophie , Spöttel Jenny , Krell Mareike , Hanschen Franziska S. , Arvandi Marjan , Binder Nadine , Schreiner Monika , Rohn Sascha , Lamy Evelyn 

TITLE=A monocentric, randomized, double-blind, controlled crossover trial of nasturtium (Tropaeolum majus) on the lipid regulator prostaglandin E2

JOURNAL=Frontiers in Nutrition

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2023.1223158

DOI=10.3389/fnut.2023.1223158

ISSN=2296-861X

ABSTRACT=<sec><title>Scope</title><p>As prostaglandin E2 (PGE<sub>2</sub>) has important roles in physiological and inflammatory functions, a double-blind randomized controlled crossover study to investigate the potential of nasturtium (<italic>Tropaeolum majus</italic>) for modulating PGE<sub>2</sub> was conducted, aiming at clarifying the role of benzyl isothiocyanate (BITC). As secondary parameters leukotriene 4 (LTB<sub>4</sub>), and cytokine release (tumor necrosis factor alpha, TNF-α; interleukins IL-1β, IL-10, and IL-12) were quantified.</p></sec><sec><title>Methods and results</title><p>Thirty-four healthy female participants consumed 1.5 g nasturtium containing BITC, (<italic>verum</italic>) or no BITC (control) twice a day for 2 weeks each. Nasturtium intervention resulted in an increase in mean PGE<sub>2</sub> levels in serum samples (<italic>verum</italic>: 1.76-fold, <italic>p</italic> ≤ 0.05; control: 1.78-fold, <italic>p</italic> ≤ 0.01), and <italic>ex vivo</italic> stimulated peripheral blood mononuclear cells (PBMC) (<italic>verum</italic>: 1.71-fold, <italic>p</italic> ≤ 0.01; control: 1.43-fold). Using a pre-to-post responder analysis approach, 18 of 34 subjects showed <italic>a</italic> &gt; 25% PGE<sub>2</sub> increase in serum, while it was &gt;25% decreased for 9 subjects (stimulated PBMC: 14 and 8 of 28, respectively). Under the selected conditions, the BITC content of nasturtium did not affect the observed changes in PGE<sub>2</sub>. <italic>Verum</italic> intervention also increased mean LTB<sub>4</sub> serum level (1.24-fold, <italic>p</italic> ≤ 0.01), but not in LPS stimulated PBMC, and significantly increased TNF-<italic>α</italic> release in stimulated PBMC after 3 h (<italic>verum</italic>: 1.65-fold, <italic>p</italic> = 0.0032; control: 1.22-fold, <italic>p</italic> = 0.7818). No change was seen in the anti-inflammatory cytokine IL-10, or the pro-inflammatory cytokines IL-1β, and IL-12.</p></sec><sec><title>Conclusion</title><p>In contrast to the previously reported <italic>in vitro</italic> results, on average, LPS activated PBMC and serum from both groups showed increased PGE<sub>2</sub> levels. Further analyses suggest that PGE<sub>2</sub> release after intervention could possibly depend on the baseline PGE<sub>2</sub> level. Identification of phenotypes that respond differently to the nasturtium intervention could be useful to establish personalized approaches for dosing phytopharmaceuticals medicines.</p></sec>