Red raspberry (Rubus idaeus) consumption attenuates inflammation in the obese Zucker rat, a model of the Metabolic Syndrome (OR24-01-19)

Abstract

ObjectivesMetabolic syndrome (MetS) is a major public health problem that is escalating quickly globally. MetS is defined as a combination of obesity, high blood pressure, high blood glucose, low high-density lipoprotein and high cholesterol resulting in a pro-thrombotic and pro-inflammatory state. This study investigated the effect of whole red raspberry (WRR) consumption on inflammation in the obese Zucker rat (OZR), a model of the MetS. MethodsAt 8 weeks of age, male OZR (n = 16) and their lean littermates (LZR) (n = 16) were placed on a control (C) or an 8% w/w WRR-enriched diet for 8 weeks. Body weight and daily food consumption was measured. Circulating levels of inflammatory cytokines and their gene expression in the liver and adipose tissue (AT) were evaluated. ResultsNo significant differences were observed in body weight or food consumption between diet groups. Consumption of WRR significantly reduced the plasma level of pro-inflammatory molecule, C-reactive protein (CRP) in the OZR compared to OZR-C (1024 ± 108.74 μg/ml vs 4250 ± 1120.12 μg/ml, p < 0.05) respectively. Plasma levels of interleukin-6 (IL-6), a pro-inflammatory cytokine decreased in the OZR consuming a WRR diet compared to the OZR-C (20.69 ± 1.41 pg/ml vs 50.50 ± 3.66 pg/ml, p < 0.0001) respectively. Following the consumption of WRR, the expression of pro-inflammatory molecules IL-6 and tumor necrosis factor-alpha (TNF-α) in the OZR significantly down-regulated (p < 0.01 and p < 0.05) respectively, in the AT. The expression of pro-inflammatory markers IL-6, TNF-α, and nuclear factor kappa-B (NF-ΚB) also significantly down-regulated (p < 0.01, p < 0.0001 and p < 0.05) respectively, following the consumption of WRR in the OZR compared to the OZR-C. ConclusionsThe results from the present study demonstrate that daily consumption of WRR improves the pro-inflammatory state associated with MetS. Funding SourcesNational Processed Raspberry Council USDA National Institute of Food and Agriculture Hatch FutureCeuticals (Momence, IL USA)