Effects of Chronic Salt Loading on Plasma Inflammatory Factors in Normotensive Adults / 中国循环杂志

ABSTRACT

Objectives: To observe the effects of dietary sodium intake on plasma inflammatory factors including tumor necrosis factor alpha (TNF-α), high-sensitivity C-reactive protein (CRP) and monocyte chemoattractant protein -1 (MCP-1) in normotensive adults. Methods: Thirty normotensive volunteers, aged 18 to 60 years old, were selected to undergo baseline survey, low-sodium diet (51.3 mmol per day) for 7 days, followed by high-sodium diet (307.8 mmol per day) for 7days. Subjects were classified as salt sensitive (SS, 10 subjects) or non-salt sensitive (NSS, 20 subjects) based on their mean arterial blood pressure (MAP) increase (SS more than 10 percent increase at the end of the high-sodium phase compared with the end of low-sodium phase). Fasting blood samples were taken on the first day of baseline and on the sixth day of the two intervention phases. Plasma TNF-α and MCP-1 concentration was measured using an enzyme-linked immunosorbent assay system, plasma hs-CRP concentration was measured by immune nephelometry. Results: The prevalence of SS is 33%. After salt loading, no significant change was found in the plasma hs-CRP concentrations; Whereas plasma TNF-α level increased significantly in both of the SS and NSS groups(pg/ml, [168.4±67.8 vs 42.1±26.7], P<0.01 and [129.8±24.1 vs 37.7±15.8], P<0.01, respectively) ; Plasma MCP-1 was also significantly higher during the high-sodium than the low-sodium phase in both SS and NSS groups(pg/ml, [205.2±64.2 vs 166.3±48.5], P<0.01and [212.3±52.2 vs 143.6±55.9], P<0.01). Conclusions: High-sodium diet can induce an inflammatory state independent of the salt sensitivity in normotensive subjects.