title: Soy protein supports cardiovascular health by downregulating hydroxymethylglutaryl-coenzyme A reductase and sterol regulatory element-binding protein-2 and increasing antioxidant enzyme activity in rats with dextran sodium sulfate-induced mild systemic inflammation.
abstract: Animal and human studies have indicated that the presence of soy in the diet improves cardiovascular health. Inflammation plays a pivotal role in the progression of cardiovascular disease (CVD). However, little is known about how dextran sodium sulfate (DSS)-induced systemic inflammation impacts overall heart health and, correspondingly, how soy protein modulates risk of CVD development in DSS-induced systemic inflammation. We hypothesized that soy protein-fed rats would have a lower risk of CVD by beneficial alteration of gene expression involving lipid metabolism and antioxidant capacity in DSS-induced systemic inflammation. Forty Sprague-Dawley rats were divided into 4 groups: casein, casein + DSS, soy protein, and soy protein + DSS. After 26 days, inflammation was induced in one group from each diet by incorporating 3% DSS in drinking water for 48 hours. Soy protein-fed rats had lower final body weights (P = .010), epididymal fat weights (P = .049), total cholesterol (P < .001), and low-density lipoprotein cholesterol (P < .001). In regard to gene expression, soy protein-fed rats had lower sterol regulatory element-binding protein-2 (P = .032) and hydroxymethylglutaryl-coenzyme A reductase (P = .028) levels and higher low-density lipoprotein receptor levels (P = .036). Antioxidant enzyme activity of superoxide dismutase and catalase was higher among the soy protein groups (P = .037 and P = .002, respectively). These results suggest that soy protein positively influences cardiovascular health by regulating serum lipids through modified expression of sterol regulatory element-binding protein-2 and its downstream genes (ie, hydroxymethylglutaryl-coenzyme A reductase and low-density lipoprotein receptor) and by promoting the antioxidant enzyme activity of superoxide dismutase and catalase.
authors.affiliation: School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA.
authors.forename: Tanya G
authors.initials: TG
authors.lastname: Marsh
authors.forename: Rachel K
authors.initials: RK
authors.lastname: Straub
authors.forename: Fatima
authors.initials: F
authors.lastname: Villalobos
authors.forename: Mee Young
authors.initials: MY
authors.lastname: Hong
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001835:Body Weight / Q000187:drug effects; D002318:Cardiovascular Diseases / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D002374:Catalase / Q000378:metabolism; D016264:Dextran Sulfate; D015536:Down-Regulation; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D015870:Gene Expression / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism*; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D050356:Lipid Metabolism / Q000187:drug effects*; D008055:Lipids / Q000097:blood; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D030262:Soybean Proteins / Q000494:pharmacology* / Q000627:therapeutic use; D013025:Glycine max / Q000737:chemistry; D051782:Sterol Regulatory Element Binding Protein 2 / Q000235:genetics / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004791:Enzyme Inhibitors; D008055:Lipids; D030262:Soybean Proteins; D051782:Sterol Regulatory Element Binding Protein 2; D016264:Dextran Sulfate; D006903:Hydroxymethylglutaryl CoA Reductases; D002374:Catalase; D013482:Superoxide Dismutase