Author + information
- Liu Fuqiang1,2,
- Chao Chu2,2,
- Junjian Mu2,
- Yong Zhang1,
- Junkui Wang1,
- Gongchang Guan1 and
- Fuqiang Liu1,2
The mechanisms of salt sensitivity as an important intermediate phenotype of essential hypertension remain elusive. Evidences show that salt could modulate adiponectin level in normal individuals. Therefore, we hypothesized that abnormalities of adiponectin and inflammation may be the potential mechanism of salt sensitivity.
Subjects (n = 334) from 124 families were selected from a rural community of Northern China. All of the people were sequentially maintained on 3 days baseline investigate, a low-salt diet for 7 days (3 g/day, NaCl), then a high-salt diet for 7 days (18 g/day). Salt-sensitivity was diagnosed in 10 subjects who exhibited a response of the increase in mean BP by ≥10% from low-salt period to high-salt period. The concentration of plasma adiponectin was measured by an immunoenzyme method (ELL SA). A total of seven single nucleotide polymorphisms (SNPs) in the were selected from adiponectin gene. Single marker and haplotype analyses were conducted using the Family Based Association Test program.
Plasma adiponectin higher significantly in high salt intake than low salt diet(6.1±1.3 vs 7.1±1.7μg/ml, P=0.047) in normotensive salt resistant subjects but not in normotensive salt sensitive subjects (6.4±2 vs 5.9±2.1μg/ml, P=0.481). After adjustment for multiple testing, the adiponectin SNP rs16861205 was significantly associated with the DBP response to low-salt intervention and the DBP and MAP responses to high-salt intervention (P = 0.028, 0.023, 0.027 respectively). SNP rs822394 was associated with the DBP and MAP responses to low-salt intervention and the DBP response to high-salt intervention (P = 0.023, 0.030, 0.033 respectively).
Our data indicates that the disturbance of adiponectin exists in normotensive salt sensitive subjects during high salt diet, which may be a novel underlying mechanism of salt sensitivity. Adiponectin gene variationmight be mechanistically involved in the salt sensitivity.