Consumption of dairy yogurt with the polysaccharide rhamnogalacturonan from the peel of the Korean citrus hallabong enhances immune function and attenuates the inflammatory response

Abstract

The aim of this study was to investigate the impact of consuming dairy yogurt supplemented with rhamnogalacturonan (RG), a polysaccharide from the peel of the Korean citrus hallabong, on natural killer (NK) cell activity and circulating cytokine levels. A randomized, double-blind, placebo-controlled study was conducted on 120 nondiabetic and nonobese subjects. Over an eight-week period, the test group consumed one pack (150 mL) of dairy yogurt containing 50 mg of probiotics and 100 mg of hallabong peel polysaccharide (60% RG) each day, whereas the placebo group consumed the same product without the hallabong peel supplement. NK cell activity (%) was measured based on the ratios of the effector cells (E; peripheral blood mononuclear cells, PBMCs) from each participant relative to the target cells (T; K562 cells) at E : T ratios of 10 : 1, 5 : 1, 2.5 : 1, or 1.25 : 1. NK cell activities under all assay conditions and interleukin (IL)-12 and interferon (IFN)-γ levels were significantly increased in the test group at eight weeks compared to the baseline values, whereas the placebo group showed a significant increase only in NK cell activity at E : T = 1.25 : 1. The test group had significantly greater increases in the changes in serum NK cell activity at the E : T ratios of 10 : 1, 5 : 1, and 2.5 : 1 and in the increases in IL-12 and IFN-γ levels than were observed in the placebo group, after adjusting for baseline values. After eight weeks of treatment, significant reductions were found in IL-6 and IL-1β levels in both the placebo and test groups. The daily consumption of dairy yogurt supplemented with RG, a polysaccharide from the peel of the Korean citrus hallabong, enhanced NK cell function and attenuated pro-inflammatory cytokine levels (ClinicalTrials.gov: NCT02535663).

Science and Healthy Meals in the World: Nutritional Epigenomics and Nutrigenetics of the Mediterranean Diet

“…Curcuma down-regulates the TNF, CXCL8, NFKB1, and PTGS2 genes, corroborating the anti-inflammatory action in dogs [79]. A polysaccharide from the peel of the Korean citrus hallabong enhances the NK cell function and attenuates the pro-inflammatory cytokine IL-12 and IFN-γ levels in a placebo-controlled study [80]. Moreover, a significant anticancer effect of clove buds in a mammary carcinoma model in vivo and in vitro has been documented as being capable of modulating histone modification [81] and DNA methylation [82].…”

Natural Killer Cell Activity and Interleukin-12 in Metabolically Healthy versus Metabolically Unhealthy Overweight Individuals

“…Detailed descriptions are provided in previous published study ( 17 ) and described in Data S3 in Presentation S3 in Supplementary Material. Whole blood was mixed with RPMI 1640 medium (ratio of 1:1) and Histopaque-1077 gradient was used for separation.…”

“…Detailed descriptions are provided in previous published study ( 17 ) described in Data S4 in Presentation S4 in Supplementary Material. To assay NK cell cytotoxic activity, isolated PBMCs (effector cells, E), which firstly incubated with K-562 cells, were seeded with 2 × 10 4 K-562 cells (target cells, T) with the four serial dilutions (E:T ratios of 10:1, 5:1, 2.5:1, and 1.25:1).…”

The Extraction, Functionalities and Applications of Plant Polysaccharides in Fermented Foods: A Review

“…After 8 weeks of therapy, the testing group showed considerable decreases in IL-6 and IL-1 levels compared to the placebo group. These results highlight the possible use of RG yogurt in nutritional supplements as a route to improve immune efficiency and decrease chronic inflammation [ 134 ]. As a result, adding prebiotic polysaccharides to fermented materials would boost the products’ anti-hypertensive and anti-diabetic characteristics studied in vitro.…”