Decreasing the Ratio of Dietary Linoleic to α-Linolenic Acid from 10 to 4 by Changing Only the Former Does Not Prevent Adiposity or Bone Deterioration in Obese Mice. Issue 6 (5th March 2020)

• Record Type: Journal Article
• Authors: Cao, Jay J; Gregoire, Brian R; Michelsen, Kim G; Picklo Sr, Matthew J
• Is Part Of: Journal of nutrition. Volume 150:Issue 6(2020)
• Page Start: 1370
• Page End: 1378
• Publication Date: 2020-03-05
• Subjects: linoleic acid -- α-linolenic acid -- ratio of LA to ALA -- bone structure -- obesity -- high-fat diet; Nutrition -- Periodicals; Diet -- Periodicals; 613.205
• DOI: 10.1093/jn/nxaa044
• Languages: English
• ISSNs: 0022-3166

Abstract

ABSTRACT: Background: Linoleic acid (LA; 18:2n–6) has been considered to promote low-grade chronic inflammation and adiposity. Studies show adiposity and inflammation are inversely associated with bone mass. Objectives: This study tested the hypothesis that decreasing the dietary ratio of LA to α-linolenic acid (ALA, 18:3n–3), while keeping ALA constant, mitigates high-fat diet (HF)-induced adiposity and bone loss. Methods: Male C57BL/6 mice at 6 wk old were assigned to 4 treatment groups and fed 1 of the following diets ad libitum for 6 mo: a normal-fat diet (NF; 3.85 kcal/g and 10% energy as fat) with the ratio of the PUFAs LA to ALA at 6; or HFs (4.73 kcal/g and 45% energy as fat) with the ratio of LA to ALA at 10:1, 7:1, or 4:1, respectively. ALA content in the diets was kept the same for all groups at 1% energy. Bone structure, body composition, bone-related cytokines in serum, and gene expression in bone were measured. Data were analyzed using 1-factor ANOVA. Results: Compared with those fed the NF, mice fed the HFs had 19.6% higher fat mass ( P < 0.01) and 13.5% higher concentration of serum tartrate-resistant acid phosphatase (TRAP) ( P < 0.05), a bone resorption cytokine. Mice fed the HFs had 19.5% and 12.2% lower tibial and second lumbar vertebral bone mass, respectively ( P < 0.01). Decreasing the dietary ratio of LA to ALA from 10 to 4 did not affect body mass, fat mass, serum TRAP and TNF-α, or any bone structural parameters. Conclusions: These data indicate that decreasing the dietary ratio of LA to ALA from 10 to 4 by simply reducing LA intake does not prevent adiposity or improve bone structure in obese mice.