Dietary Flavonoids from Modified Apple Reduce Inflammation Markers and Modulate Gut Microbiota in Mice

Abstract

Apples are rich in polyphenols, which provide antioxidant properties, mediation of cellular processes such as inflammation, and modulation of gut microbiota. In this study we compared genetically engineered apples with increased flavonoids [myeloblastis transcription factor 10 (MYB10)] with nontransformed apples from the same genotype, "Royal Gala" (RG), and a control diet with no apple. Compared with the RG diet, the MYB10 diet contained elevated concentrations of the flavonoid subclasses anthocyanins, flavanol monomers (epicatechin) and oligomers (procyanidin B2), and flavonols (quercetin glycosides), but other plant secondary metabolites were largely unaltered. We used these apples to investigate the effects of dietary flavonoids on inflammation and gut microbiota in 2 mouse feeding trials. In trial 1, male mice were fed a control diet or diets supplemented with 20% MYB10 apple flesh and peel (MYB-FP) or RG apple flesh and peel (RG-FP) for 7 d. In trial 2, male mice were fed MYB-FP or RG-FP diets or diets supplemented with 20% MYB10 apple flesh or RG apple flesh for 7 or 21 d. In trial 1, the transcription levels of inflammation-linked genes in mice showed decreases of >2-fold for interleukin-2 receptor (Il2rb), chemokine receptor 2 (Ccr2), chemokine ligand 10 (Cxcl10), and chemokine receptor 10 (Ccr10) at 7 d for the MYB-FP diet compared with the RG-FP diet (P < 0.05). In trial 2, the inflammation marker prostaglandin E(2) (PGE(2)) in the plasma of mice fed the MYB-FP diet at 21 d was reduced by 10-fold (P < 0.01) compared with the RG-FP diet. In colonic microbiota, the number of total bacteria for mice fed the MYB-FP diet was 6% higher than for mice fed the control diet at 21 d (P = 0.01). In summary, high-flavonoid apple was associated with decreases in some inflammation markers and changes in gut microbiota when fed to healthy mice.

Quercetin Inhibits Pacemaker Potentials via Nitric Oxide/cGMP-Dependent Activation and TRPM7/ANO1 Channels in Cultured Interstitial Cells of Cajal from Mouse Small Intestine

“…Furthermore, quercetin was found to be associated with decreases in some inflammation markers and changes in gut microbiota when administered to healthy mice [64]. In the present study, quercetin inhibited ICCs pacemaker activity and suppressed ITR in mice.…”

Biologically Active Triterpenoids and Their Cardioprotective and Anti- Inflammatory Effects

“…In the wax of the apple peels [9], ursolic acid ((3β)-3-hydroxyurs-12-en-28-oic acid) and oleanoic acid (3β-hydroxyolean-12-en-28-oic acid) derivatives with hydroxyl, oxo, and coumaroyloxy groups were found [16]. Through the measurement of differences between inflammation-related gene expression and markers and bacterial populations in mice and humans fed specific diets containing different apples, it was determined that apple peel extracts containing these triterpenoids could induce antioxidant concentrations in plasma and serum while reducing damage in DNA, inflammation, and oxidative stress levels [17].…”

“…By reducing the risk of atherosclerosis, cardiovascular disease risk may be reduced [99]. Apple peel triterpenoids also used antioxidant mechanism in plasma and serum to reduce the damage in DNA, inflammation, and oxidative stress levels [17]. Ursolic acid activated mechanism regulating Mcl-1 pro-apoptotic protein to reduce adverse consequences of heat stress in cardiomyocytes [4] and mediated anti-apoptotic and antioxidative activities against endoplasmic reticulum (ER) stress-associated myocardial damage.…”

Polyphenols-rich fruit in maternal diet modulates inflammatory markers and the gut microbiota and improves colonic expression of ZO-1 in offspring

“…Thus, the anti-inflammatory effect of polyphenols possibly involves underlying mechanisms related to their functions in the intestine and interactions with the gut microbiota (Espley et al, 2014;Neyrinck et al, 2013). Since these compounds are not metabolized and absorbed in the intestine, they reach the proximal colon and are degraded to phenolic acids by microbiota (Faria, Fernandes, Norberto, Mateus, & Calhau, 2014;Neyrinck et al, 2013;Talavéra et al, 2005).…”

“…Additionally, a reduction in inflammatory markers and an increase in Bifidobacterium spp. relative to the total bacteria in the colon of animals treated with flavonoid-rich fruit has been demonstrated (Espley et al, 2014).…”