(P03-087-23) Green Tea Extract Confection Alleviates Endotoxemia Without Affecting Systemic Inflammation in Healthy Adults and Those With Metabolic Syndrome

Objectives: Catechin-rich green tea extract (GTE) decreased intestinal and systemic inflammation in obese rodents, and reduced small intestinal permeability in persons with metabolic syndrome (MetS) and healthy persons. Based on these findings, we hypothesized that GTE would decrease metabolic endotoxemia and endotoxin-associated inflammation.

Methods: In a randomized, double-blind, placebo-controlled crossover study, persons with MetS and healthy persons completed two 28-d interventions with GTE confections (890 mg/d total catechins) or matched-placebo confections while following a low-polyphenol diet. On days 0 (PRE), 14 (MID), and 28 (POST), anthropometrics, 3-d food records, and fasting blood samples were obtained. Plasma catechins and valerolactones were quantified by LC/MS. Endotoxin was measured using a recombinant factor-C (rFC)-based fluorometric assay. Expression of pro-inflammatory genes at POST was assessed by RT-qPCR. Data were analyzed by repeated measures ANOVA.

Results: MetS (n = 21; 40 ± 3 y) and healthy (n = 19; 34 ± 2 y) adults completed the study with high compliance ( >95% of confections consumed) without affecting body mass and blood hematocrit and no adverse events were observed. Aminotransferases were higher in MetS, but unaffected by GTE regardless of health status. Dietary polyphenol intakes were lower (P < 0.0001) at MID and POST regardless of health status and treatment. Plasma catechins and valerolactones were marginally detectable at PRE, but increased (P ≤ 0.0001) at MID and POST in the GTE arm regardless of health status as expected. Although serum endotoxin was lower at POST in GTE regardless of health status, whole blood mRNA expression of CD14, MCP1, MD2, MyD88, MPO, IL6, IL8, TNFα, TLR4, p65 were unaffected.

Conclusions: Findings of this 1-mo intervention support that catechin-rich GTE confection alleviates metabolic endotoxemia while safely increasing circulating catechins and their microbial metabolites. That these benefits occurred regardless of MetS status suggests preventative and therapeutic bioactivities of green tea.

Funding Sources: USDA-NIFA, USDA-HATCH, and the Ohio Agricultural Research and Development Center at The Ohio State University.