A Citrus and Pomegranate Complex Reduces Methylglyoxal in Healthy Elderly Subjects: Secondary Analysis of a Double-Blind Randomized Cross-Over Clinical Trial.

Katarzyna Bednarska, Izabela Fecka, Jean L J M Scheijen, Sanne Ahles, Philippe Vangrieken, Casper G Schalkwijk

Journal: International journal of molecular sciences 2023;24(17):13168

PMID: 37685975

Plain Language Summary

Vascular complications are prevalent in people with diabetes which plays a role in diabetes-related mortality. α-dicarbonyl compounds are highly reactive compounds which are involved in the pathogenesis of Type 2 diabetes, vascular complications and other age-related health complications. Endogenous α-dicarbonyl compounds (α-DCs) such as methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG) can react with amino acids and produce advanced glycation end-products (AGEs). AGEs are harmful compounds that are active in increasing oxidative stress and inflammation involved in vascular complications, and cardiometabolic and neurodegenerative diseases. Reducing the systemic levels of methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG) can significantly impede the formation of advanced glycation end products (AGEs). This holds particular significance for patients suffering from pathophysiological increases in α-dicarbonyl compounds (α-DCs) due to diabetes. Previous research has shown that citrus and pomegranate polyphenols can prevent the formation of AGEs by scavenging α-DCs. This secondary analysis of a double-blind, randomised, cross-over clinical trial in thirty-six healthy elderly participants investigated the impact of 700 mg citrus extract and pomegranate concentrate (CPC) supplementation for four weeks on α-DCs levels. The results of this study showed a significant reduction in MGO followed by CPC supplementation in elderly people. Healthcare professionals can use the results of the study to understand the beneficial effects of CPC in impeding α-DCs levels and AGEs and ameliorating inflammation and oxidative stress in elderly people. Further robust studies are required to evaluate the long-term effects of CPC supplementation in elderly people with serious diseases.

Abstract

["Reactive \u03b1-dicarbonyls (\u03b1-DCs), such as methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG), are potent precursors in the formation of advanced glycation end products (AGEs). In particular, MGO and MGO-derived AGEs are thought to be involved in the development of vascular complications in diabetes. Experimental studies showed that citrus and pomegranate polyphenols can scavenge \u03b1-DCs. Therefore, the aim of this study was to evaluate the effect of a citrus and pomegranate complex (CPC) on the \u03b1-DCs plasma levels in a double-blind, placebo-controlled cross-over trial, where thirty-six elderly subjects were enrolled. They received either 500 mg of peel extract and 200 mg of concentrate in CPC capsules or placebo capsules for 4 weeks, with a 4-week washout period in between. For the determination of \u03b1-DCs concentrations, liquid chromatography tandem mass spectrometry was used. Following four weeks of CPC supplementation, plasma levels of MGO decreased by 9.8% (-18.7 nmol\/L; 95% CI: -36.7, -0.7 nmol\/L; = 0.042). Our findings suggest that CPC supplementation may represent a promising strategy for mitigating the conditions associated with MGO involvement. This study was registered on clinicaltrials.gov as NCT03781999."]

Address: Department of Pharmacognosy, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211, 50-556 Wroclaw, Poland.; The Committee on Therapeutics and Pharmaceutical Sciences, The Polish Academy of Sciences, Pl. Defilad 1, 00-901 Warsaw, Poland.; Department of Internal Medicine, Maastricht University Medical Center+, 6229 ER Maastricht, The Netherlands.; CARIM School for Cardiovascular Diseases, Faculty of Health, Medicine and Life Sciences, Maastricht University, 6229 ER Maastricht, The Netherlands.; Department of Nutrition and Movement Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, 6229 ER Maastricht, The Netherlands.; BioActor BV, 6229 GS Maastricht, The Netherlands.

DOI: 10.3390/ijms241713168