Monovalerin and trivalerin increase brain acetic acid, decrease liver succinic acid, and alter gut microbiota in rats fed high-fat diets

• Published in: European journal of nutrition Vol. 58; no. 4; pp. 1545 - 1560
• Main Authors: Nguyen, Thao Duy, Prykhodko, Olena, Fåk Hållenius, Frida, Nyman, Margareta
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-06-2019; Springer Nature B.V
• Subjects: Acetic acid; Acetic Acid - metabolism; Animals; Annan teknik; Anti-inflammatory agents; Bacteroidetes; Biomarkers; Blood; Brain - drug effects; Brain - metabolism; Chemistry; Chemistry and Materials Science; Diet; Diet, High-Fat; Dietary supplements; Engineering and Technology; Esters; Fatty acids; Food Engineering; Gastrointestinal Microbiome - drug effects; High density lipoprotein; High fat diet; Inflammation; Intestinal microflora; Lipopolysaccharide-binding protein; Liver; Liver - drug effects; Liver - metabolism; Livsmedelsteknik; Low density lipoprotein; Low fat diet; Male; Metabolites; Microbiota; Models, Animal; Nutrient deficiency; Nutrition; Original Contribution; Other Engineering and Technologies; Pentanoic Acids - pharmacology; Rats; Rats, Wistar; Rodents; Succinic acid; Succinic Acid - metabolism; Teknik; Valeric acid; Valeric acid; Succinic acid; Acetic acid; Caecal microbiota; SCFA
• ISSN: 1436-6207; 1436-6215; 1436-6215
• DOI: 10.1007/s00394-018-1688-z

Purpose
Short-chain fatty acids (SCFA) are known for their anti-inflammatory properties and may also prevent against the development of metabolic diseases. This study investigated possible effects of two valeric acid esters, monovalerin (MV) and trivalerin (TV) in rats fed high-fat diets.
Methods
Four groups of rats were given a low-fat diet (LF) or a high-fat control diet (HFC) with or without supplementation of MV or TV (5 g/kg) for 3 weeks (
n
 = 7/group). SCFA (caecum, blood, liver and brain), succinic acid (liver), microbiota (caecum), lipid profile (liver and blood) and the inflammatory biomarker, lipopolysaccharide-binding protein (blood) were analysed at the end of the experiment.
Results
Supplementation of MV and TV to a high-fat diet increased 1.5-fold the amounts of acetic acid in the brain and 1.7-fold serum concentration of valeric acid, whereas liver succinic acid was reduced by 1.5-fold. Although liver triglyceride levels were higher in both MV and TV groups compared with the LF group, liver LDL/HDL ratio was lower in the MV group (
P
 < 0.05). The caecal microbiota composition was altered, with threefold higher abundance of Bacteroidetes and higher ratio of Bacteroidetes/Firmicutes in the MV group compared with the HFC and LF groups. Acetic acid in the brain was negatively correlated with TM7, family S24-7 and
rc4-4
, and positively associated to Tenericutes and
Anaeroplasma
.
Conclusions
The present study shows that MV and TV in the specified dose can affect caecal microbiota composition and, therefore, bacterial metabolites in the liver, serum and brain as well as the lipid profile in the liver.