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bioRxiv · 10.1101/2021.08.05.455257

Knockout of murine Lyplal1 confers sex-specific protection against diet-induced obesity

Abstract

Human genome-wide association studies found SNPs near LYPLAL1 that have sex-specific effects on fat distribution and metabolic traits. To determine whether altering LYPLAL1 affects obesity and metabolic disease we created and characterized a mouse knockout of Lyplal1. Here we show that CRISPR-Cas9 whole-body Lyplal1 knockout (KO) mice fed a high fat, high sucrose (HFHS) diet showed sex-specific differences in weight gain and fat accumulation. Female, not male, KO mice weighed less than WT mice, had reduced body fat percentage, white fat mass, and adipocyte diameter not accounted for by changes in metabolic rate. Female, but not male, KO mice had increased serum triglycerides, decreased aspartate, and alanine aminotransferase. Lyplal1 KO mice of both sexes have reduced liver triglycerides and steatosis. These diet-specific effects resemble the effects of SNPs near LYPLAL1 in humans, suggesting that LYPLAL1 has an evolutionary conserved sex-specific effect on adiposity. This murine model can be used to study this novel gene-by-sex-by-diet interaction to elucidate the metabolic effects of LYPLAL1 on human obesity.

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BibTeXRIS

Vohnoutka, R. B., Kuppa, A., Hegde, Y., Chen, Y., Pant, A., Choi, E.-Y. K., McCarty, S. M., Bagchi, D., Du, X., Chen, V. L., Bielak, L. F., Maguire, L. H., Handelman, S. K., Sexton, J. Z., Saunders, T., Halligan, B. D., Speliotes, E. K.. 2021-08-05. Knockout of murine Lyplal1 confers sex-specific protection against diet-induced obesity. https://doi.org/10.1101/2021.08.05.455257

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