title: Elevation of Fasting Ghrelin in Healthy Human Subjects Consuming a High-Salt Diet: A Novel Mechanism of Obesity?
abstract: Overweight/obesity is a chronic disease that carries an increased risk of hypertension, diabetes mellitus, and premature death. Several epidemiological studies have demonstrated a clear relationship between salt intake and obesity, but the pathophysiologic mechanisms remain unknown. We hypothesized that ghrelin, which regulates appetite, food intake, and fat deposition, becomes elevated when one consumes a high-salt diet, contributing to the progression of obesity. We, therefore, investigated fasting ghrelin concentrations during a high-salt diet. Thirty-eight non-obese and normotensive subjects (aged 25 to 50 years) were selected from a rural community in Northern China. They were sequentially maintained on a normal diet for three days at baseline, a low-salt diet for seven days (3 g/day, NaCl), then a high-salt diet for seven days (18 g/day). The concentration of plasma ghrelin was measured using an immunoenzyme method (ELISA). High-salt intake significantly increased fasting ghrelin levels, which were higher during the high-salt diet (320.7 ± 30.6 pg/mL) than during the low-salt diet (172.9 ± 8.9 pg/mL). The comparison of ghrelin levels between the different salt diets was statistically-significantly different (p < 0.01). A positive correlation between 24-h urinary sodium excretion and fasting ghrelin levels was demonstrated. Our data indicate that a high-salt diet elevates fasting ghrelin in healthy human subjects, which may be a novel underlying mechanism of obesity.
authors.affiliation: Cardiovascular Department, Shaanxi Provincial People's Hospital, Xi'an 710068, China. zhangyong971292@163.com.|Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. zhangyong971292@163.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Cardiovascular Department, Second Affiliated Hospital, Xi'an Medical University, Xi'an 710038, China. lfenxia@sina.com.
authors.forename: Fenxia
authors.initials: F
authors.lastname: Li
authors.affiliation: Cardiovascular Department, Shaanxi Provincial People's Hospital, Xi'an 710068, China. liufuqiang0909@163.com.|Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. liufuqiang0909@163.com.
authors.forename: Fu-Qiang
authors.initials: FQ
authors.lastname: Liu
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. iaacd@163.com.
authors.forename: Chao
authors.initials: C
authors.lastname: Chu
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. wangyangxxk@126.com.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. m15991631129@163.com.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. 215guotongshuai@163.com.
authors.forename: Tong-Shuai
authors.initials: TS
authors.lastname: Guo
authors.affiliation: Cardiovascular Department, Shaanxi Provincial People's Hospital, Xi'an 710068, China. cardiowang@163.com.
authors.forename: Jun-Kui
authors.initials: JK
authors.lastname: Wang
authors.affiliation: Cardiovascular Department, Shaanxi Provincial People's Hospital, Xi'an 710068, China. ntxhx2005@stu.xjtu.edu.cn.|Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. ntxhx2005@stu.xjtu.edu.cn.
authors.forename: Gong-Chang
authors.initials: GC
authors.lastname: Guan
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. peizirong@yeah.net.
authors.forename: Ke-Yu
authors.initials: KY
authors.lastname: Ren
authors.affiliation: Cardiovascular Department, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061, China. mu_jjun@163.com.
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Mu
mesh_terms: D000328:Adult; D001069:Appetite Regulation; D015415:Biomarkers / Q000097:blood / Q000652:urine; D015992:Body Mass Index; D002681:China / Q000453:epidemiology; D018592:Cross-Over Studies; D004032:Diet / Q000009:adverse effects* / Q000208:ethnology; D004039:Diet, Sodium-Restricted / Q000208:ethnology; D005260:Female; D054439:Ghrelin / Q000097:blood*; D006801:Humans; D006963:Hyperphagia / Q000208:ethnology / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology* / Q000517:prevention & control; D058246:Prehypertension / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology / Q000517:prevention & control; D012307:Risk Factors; D012423:Rural Health / Q000208:ethnology; D012964:Sodium / Q000652:urine; D017673:Sodium Chloride, Dietary / Q000009:adverse effects*; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; C515349:GHRL protein, human; D054439:Ghrelin; D017673:Sodium Chloride, Dietary; D012964:Sodium
keywords: diet intervention; ghrelin; high salt; obesity