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bioRxiv · 10.1101/2023.01.31.526123

Metabolic impact of trans 10, cis 12-conjugated linoleic acid in pai transgenic mice

Rao, Y.·Li, S. L.·Li, M. J.·Wang, B. Z.·Wang, Y. Y.·Liang, L. W.·Yu, S.·Liu, Z. P.·Cui, S.·GOU, K. M.
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Abstract

Trans 10, cis 12-conjugated linoleic acid (t10c12-CLA) from ruminant-derived foodstuffs can induce body fat loss in mammals after oral administration, while its mechanism on fat reduction has yet to be clarified fully until now. In the current study, a transgenic mouse that produced t10c12-CLA had been generated by inserting the Propionibacterium acnes isomerase (Pai) expression cassette into the Rosa26 locus, and its male offspring were used to decipher an irreversible long-term impact of t10c12-CLA on health and its mechanism of action. Compared to their wild-type C57BL/6J littermates, comprehensive phenotype profiling of biallelic pai/pai mice indicated that white fat was decreased while brown fat was increased reversely; meanwhile, more heat was released and the central activities were reduced. Besides decreased plasma triglycerides in both pai genotypes and increased serum FGF21 in pai/wt mice, RNA and protein analysis revealed that the fatty acid oxidation and thermogenesis capacity of brown adipose tissues were elevated via CPT1B and UCP1/2 over-expression. The results indicate that the t10c12-CLA-induced fat loss might be caused by the excess FGF21 and the increased mass and extra thermogenesis of brown adipose tissue in transgenic mice.

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Rao, Y., Li, S. L., Li, M. J., Wang, B. Z., Wang, Y. Y., Liang, L. W., Yu, S., Liu, Z. P., Cui, S., GOU, K. M.. 2023-02-03. Metabolic impact of trans 10, cis 12-conjugated linoleic acid in pai transgenic mice. https://doi.org/10.1101/2023.01.31.526123

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