Nutr Res Pract.  2016 Dec;10(6):629-634. 10.4162/nrp.2016.10.6.629.

Korean solar salts reduce obesity and alter its related markers in diet-induced obese mice

• Ju J
• Song JL
• Park ES
• Do MS
• Park KY

• KMID: 2359620
• DOI: http://doi.org/10.4162/nrp.2016.10.6.629

Abstract

BACKGROUND/OBJECTIVES
The aim of this experiments was to show anti-obesity effects of Korean solar salt from different salt fields in diet-induced obese mice.
SUBJECTS/METHODS
Diet-induced obesity (DIO) was induced by a high-fat diet (HFD; 45% cal from fat) in C57BL/6J mice for eight weeks. The mice were fed with the designated diets (chow diet for Normal, HFD for Control, 0.47%-salt-mixed HFD for purified salt (PS), Guerande solar salt from France (SS-G), solar salt from Y salt field (SS-Y), solar salts from T salt field (SS-T) and S salt field (SS-S)) for another eight weeks. We checked body weight, food efficiency ratio (FER) and tissue weights (liver and epididymal adipose tissue (EAT)), and observed serum concentrations of triacylglycerol (TG), total cholesterol (TC), leptin and insulin. We also evaluated gene expressions of adipogenic / lipogenic mRNAs of C/EBPα, PPARγ and FAS and beta-oxidation-related factors (PPARα and CPT-1) in liver and EAT. The mineral composition of salt samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES).
RESULTS
SS-T and SS-S significantly reduced body weight gain, FER, and weight of EAT compared to control and other samples (P < 0.05). SS-T and SS-S also significantly decreased serum levels of TG, TC, leptin and insulin (P < 0.05). SS-T and SS-S suppressed expressions of adipogenic / lipogenic mRNAs in liver and EAT, while promoting expression of beta-oxidation-related factors. The lowest sodium concentration was observed in SS-T (30.30 ± 0.59%), and the lowest sodium-to-potassium (Na/K) ratio was found in SS-S (17.81).
CONCLUSIONS
Our study shows that well-processed Korean solar salt may have anti-obesity effects in vivo, probably owing to its differences in mineral composition and other components, presumably resulting from the manufacturing processes. Further research is needed into the mechanism and to explore optimal manufacturing processes.

Keyword

Salt; obesity; obese mouse

MeSH Terms

Adipose Tissue
Animals
Body Weight
Cholesterol
Diet
Diet, High-Fat
France
Gene Expression
Insulin
Leptin
Liver
Mice
Mice, Obese*
Miners
Obesity*
Plasma
RNA, Messenger
Salts*
Sodium
Spectrum Analysis
Triglycerides
Weights and Measures
Cholesterol
Insulin
Leptin
RNA, Messenger
Salts
Sodium
Triglycerides

Figure

• 

  Fig. 1 Changes in serum concentrations of (A) leptin and (B) insulin by administration of salt samples to diet-induced obese mice. * Results are presented as means ± SDs (n = 3). a-d Means with the different letters on the bars are significantly different (P < 0.05) by Duncan's multiple range test.

• 

  Fig. 2 Changes in mRNA expression of obesity-related factors in (A) liver and (B) EAT by administration of salt samples to diet-induced obese mice. * Results are presented as means ± SDs (n = 3). a-g Means with the different letters on the bars are significantly different (P < 0.05) by Duncan's multiple range test.

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