Effects of salt intake serum and urinary uromodulin levels in Chinese adults / 西安交通大学学报(医学版)

ABSTRACT

【Objective】 To explore the effects of dietary salt intake on serum and urinary levels through the chronic salt loading intervention. 【Methods】 Eighty adults （18 to 65 years old） were screened from two villages in Liquan and Lantian counties to participate in a 2-week chronic salt intervention， including a 3-day baseline survey， a 7-day low-salt diet， and a 7-day high-salt diet. Uromodulin levels in serum and urine were determined by enzyme-linked immunosorbent assay （ELISA） kits. According to the baseline blood pressure levels， all subjects were divided into normotensive and hypertensive groups. Pearson or Spearman correlation analyzed the associations of 24 h urinary sodium excretions with serum and urinary levels of uromodulin. 【Results】 At the baseline， serum uromodulin in hypertensive subjects was significantly lower than that in normotensive subjects （26.7±9.9 vs. 57.9±9.7 ng/mL， P=0.033）. Serum uromodulin levels were significantly lower on a high-salt diet than on a baseline diet ［（54.9±8.8 vs. 28.3±4.5） ng/mL， P=0.007］. In addition， daily urinary excretions of uromodulin were lower on a high-salt diet ［（28.4±6.6） ng/mL］ than on a baseline diet ［（282.1±70.0） ng/mL］ and on a low-salt diet ［（154.1±21.3） ng/mL］. The 24 h urinary sodium excretions were inversely correlated with urinary uromodulin excretions （r=-0.40， P<0.001） on both low-salt and high-salt diets， but not correlated with serum uromodulin levels. 【Conclusion】 Variations in dietary salt intake significantly affect plasma and urine uromodulin levels.