Effects of Salt Loading on Plasma Osteoprotegerin Levels and Protective Role of Potassium Supplement in Normotensive Subjects.

BACKGROUND: Excess dietary salt is strongly correlated with cardiovascular disease, morbidity, and mortality. Conversely, potassium likely elicits favorable effects on cardiovascular disorders. In epidemiological studies, increased plasma osteoprotegerin (OPG) concentrations are associated with atherosclerosis and vascular deaths. Our study was designed to examine the effects of salt intake and potassium supplementation on plasma OPG levels in normotensive subjects.Methods and Results:The 18 normotensive subjects were selected from a rural community in China. They were sequentially maintained on low-salt diet for 7 days (3 g/day, NaCl), high-salt diet for 7 days (18 g/day), and high-salt diet with potassium supplementation for 7 days (18 g/day of NaCl+4.5 g/day of KCl). High-salt intake enhanced plasma OPG levels (252.7±13.9 vs. 293.4±16.1 pg/mL). This phenomenon was abolished through potassium supplementation (293.4±16.1 vs. 235.1±11.3 pg/mL). Further analyses revealed that the OPG concentration positively correlated with 24-h urinary sodium excretion (r=0.497, P<0.01). By contrast, OPG concentration negatively correlated with 24-h urinary potassium excretion (r=0.594, P<0.01). CONCLUSIONS: Salt loading can enhance the production of circulating OPG. Potassium supplementation can reverse the effects of excessive OPG. Our study results may improve our understanding of the roles of salt and potassium in the risk of cardiovascular disorders.

[Effect of xuezhikang on blood lipids, serum oxidized low density lipoprotein, C-reactive protein and fibrinogen in patients with unstable angina pectoris].

OBJECTIVE: To study the lipid regulatory effect of Xuezhikang (XZK) and its effects on serum oxidized low density lipoprotein (OX-LDL), C-reactive protein (CRP) and fibrinogen (FIB) in patients with unstable angina pectoris (UAP). METHODS: UAP patients with hyperlipidemia were treated with XZK 0.6 g, orally taken, twice a day for 2 successive months followed by half dosage for 2 months. To UAP patients with normal blood lipids, Vit E was given orally for 4 months. Levels of blood lipids, OX-LDL, CRP, FIB at the time of entry, 1st and 2nd month of the therapeutic course were observed and end-point events in the two groups was compared. RESULTS: XZK can reduce the serum level of total cholesterol, low density lipoprotein after being administered for 1 month, and the effect further elevated after 2 months. Its effect in lowering triglycerides and increasing high density lipoprotein initiated after 2 months administration. Compared with effect of Vit E, XZK can significantly lower the serum OX-LDL, CRP and FIB after 2 months administration, and reduce the end-point events in 4 months. CONCLUSION: XZK has good regulatory effect on blood lipids, it also can inhibit the development of inflammation in coronary plaque, therefore, is beneficial to the prognosis of UAP patients.