Dietary Bioactive Components
Objectives : Metabolic 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.
Methods : At 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.
Results : No 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 ± 108.74μg/ml vs 4250 ± 1120.12μg/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 ± 1.41pg/ml vs 50.50 ± 3.66pg/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.
Conclusions : The results from the present study demonstrate that daily consumption of WRR improves the pro-inflammatory state associated with MetS.
Funding Sources : National Processed Raspberry Council
USDA National Institute of Food and Agriculture Hatch
FutureCeuticals (Momence, IL USA)