Dietary fruit and vegetable supplementation suppresses diet-induced atherosclerosis in LDL receptor knockout mice

Authors: GUO, WEIMIN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; KIM, SHARON - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; WU, DAYONG - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; LI, LIJUN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; THOMAS, MICHAEL - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; MEYDANI, SIMIN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; MEYDANI, MOHSEN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University

Submitted to: American Society for Nutrition
Publication Type: Abstract Only
Publication Acceptance Date: 4/23/2019
Publication Date: 6/13/2019
Citation: Guo, W., Kim, S., Wu, D., Li, L., Thomas, M., Meydani, S.N., Meydani, M. 2019. Dietary fruit and vegetable supplementation suppresses diet-induced atherosclerosis in LDL receptor knockout mice [abstract]. American Society for Nutrition. Abstract No. OR24-07-19.

Interpretive Summary:

Technical Abstract: Objectives: Epidemiological studies have shown that consumption of fruits and vegetables (F and V) is inversely associated with incidence of cardiovascular disease (CVD). However, the evidence for causality and underlying mechanisms is lacking. Our objective was to determine if increased consumption of F and V could prevent atherosclerosis and its underlying mechanisms. Methods: A unique blend of the most commonly consumed 24 F andV was freeze-dried into a powder and mixed into diets. Thirty six 4-week old male LDL receptor knockout mice were randomly assigned to one of 3 diet groups (12 per group): low fat (LF, 10 kcal percent fat), high-fat (27 kcal percent fat) with 0 percent F and V (HF), and HF plus 15 percent F&V diet (HF plus FV, equivalent to 8-9 servings for humans). After 20 weeks, mice were euthanized and blood, aorta, and liver tissue were collected. Aortic atherosclerotic lesion, hepatic steatosis, plasma lipid profile and pro-inflammatory cytokine levels were measured. Results: No significant differences were found in body weight among the 3 groups. Mice fed HF diet had larger aortic atherosclerotic lesion and hepatic steatosis area than mice fed LF diet by 6.5 and 1.9 fold, respectively (p is less than 0.001). HF+FV group had 80 percent less aortic lesion and hepatic steatosis than HF group (p is less than 0.001). Mice fed HF diet had significantly higher plasma TG and LDL and lower HDL levels than mice fed LF diet, and this dyslipidemia was prevented by F&V supplementation. Further, HF plus FV group had lower plasma TNF alpha levels compared to HF0 group (p is less than 0.05). Spearman correlation analysis showed that aortic atherosclerotic lesion and hepatic steatosis area were negatively correlated with plasma HDL (p is less than 0.001) and significantly and positively correlated with TNF alpha, and the ratios of LDL/HDL, TG/HDL, and non HDL/HDL. Conclusions: Our results demonstrate a causal role of high intake of F&V in preventing HF-induced atherosclerosis and hepatic steatosis, which may be mediated through improved dyslipidemia and reduced inflammation.