Body Mass Index as a Determinant of Systemic Exposure to Gallotannin Metabolites during 6-Week Consumption of Mango (Mangifera indica L.) and Modulation of Intestinal Microbiota in Lean and Obese Individuals

Abstract

Scope: This human clinical pilot trial investigated pharmacokinetics of gallotannin-metabolites and modulation of intestinal microbiota in healthy lean and obese individuals after 6 weeks of daily mango consumption.

Methods and results: Participants are divided into three groups: Lean Mango (LM: n = 12; BMI = 22.9 kg m^-2 ), Obese Mango (OM: n = 9; BMI = 34.6 kg m^-2 ), and Lean Control (LC: n = 11; BMI = 22.1 kg m^-2 ). LM and OM consumed 400 g of mango per day for 6 weeks. LC consumed mango only on Days 0 and 42. After 6 weeks, LM experienced increased systemic exposure (AUC_0-8h ) to gallotannin-metabolites, 1.4-fold (p = 0.043). The greatest increase is 4-O-methyl-gallic acid, 3.3-fold (p = 0.0026). Cumulative urinary excretion of gallotannin-metabolites significantly increased in LM and OM, but not LC. For OM, qPCR data show increased levels of tannase-producing Lactococcus lactis and decreased levels of Clostridium leptum and Bacteroides thetaiotaomicron, bacteria associated with obesity. LM experienced an increased trend of fecal levels of butyric (1.3-fold; p = 0.09) and valeric acids (1.5-fold; p = 0.056). Plasma endotoxins showed a decreased trend in LM and OM.

Conclusion: Continuous mango intake significantly increased systemic exposure to gallotannin- metabolites and induced an increased trend for fecal short-chain fatty acids in lean but not obese individuals. This pharmacokinetic discrepancy may result in BMI-associated reduced gallotannin-derived health benefits.

Keywords: bioavailability; gallotannins; human clinical intervention; intestinal microbiota; mango.