Page 21 - Y. Vascular biology

Gut microbiota and Liver Transcriptome underlying
Sexual Dimorphism of Atherosclerosis
in a Hyperlipidemic Diversity Outbred F1 Mouse Population
2
2
2
Myungsuk Kim 1,2 , M. Nazmul Huda , Excel Que , Erik R. Gertz , Brian J. Bennett 1,2
1 Department of Nutrition, University of California, Davis 95616,
2 Western Human Nutrition Research Center, Davis, CA 95616
BACKGROUNDS & AIMS STUDY DESIGN & METHODS
BACKGROUNDS We collected offspring (238 female and
Atherosclerosis is a complex multifactorial disease that develops 234 male mice) from a cross between
through the interaction of various genetic and environmental transgenic male C57BL/6J mice, which
factors. Differences in atherosclerosis by sex have been well were made susceptible to
documented and altered gut microbiota and liver gene atherosclerosis by microinjection of
expressions have been associated with atherosclerosis. However, human apolipoprotein E-Leiden and
how sex influences the pathogenesis of atherosclerosis mediated cholesterol ester transfer protein genes,
by gut microbiota and liver transcripts is unclear. and ~200 female DO mice, a population
AIMS derived from 8 inbred strains. We fed
We hypothesized that the association between gut microbial the offspring a high fat/cholesterol diet
. profiles, liver transcriptome, and atherosclerosis demonstrates for 12 weeks. We then examined over
sexual dimorphism. In order to test this hypothesis, we studied 30 cardio-metabolic traits, fecal
sexual dimorphism in cardio-metabolic traits, gut microbiota, and microbiota compositions using 16S rRNA
liver gene expression using 470 hyperlipidemic Diversity Outbred gene sequencing, and global liver gene
(DO) mice. expression using RNA-sequencing.
RESULTS

Fig.1. Atherosclerosis-related physiological A Female mice B C
phenotypes in Diversity Outbred (DO)-F1 mice.
(A) Oil red O staining of representative females and
males at the 24 weeks. (B) Aortic lesion area in females
were significantly larger than males (mean ± SD). (C)
Plasma total cholesterol (TC), plasma VLDL/LDL-C, Male mice
HDL-C, hepatic TC, duodenum TC, and plasma
triglycerides (TG) levels are higher in females. P-value
for male vs. female.
Fig.2. Alpha/Beta-Diversity and association A B C D
between microbial diversity and phenotypes Shannon Diversity Observed ASVs Unweighted UniFrac Bray-Curtis
exhibit females are more susceptible to
atherosclerosis. (A) Shannon diversity and (B)
observed ASV indices by sex. (C) Unweighted UniFrac
(PERANOVA: <0.001) and (D) Bray-Curtis (PERANOVA:
<0.001) beta diversity principal coordinate plot by sex.

Fig.3. Sexually dimorphic gut microbial A Genera B ASVs C Correlation between genera and cardio-metabolic traits
abundance at each taxonomic rank in DO-F1
mice. Analysis of composition of microbiomes
(ANCOM) analysis in microbial (A) genera and (B)
amplicon sequence variants (ASVs) levels by sex. (C)
Spearman correlation between sexually dimorphic
genera and cardio-metabolic traits. The p-values were
adjusted using the Benjamini-Hochberg (BH) FDR
procedure. “***”P < 0.001, “**”P < 0.01, “*”P < 0.05,
“.”P < 0.10.
Fig.4. Sex differences in regulation of liver gene A Liver transcriptome B Top10 GO for C Top10 GO for
expression in DO-F1 mice. (A) PCA analysis in liver female-specific DEGs male-specific DEGs
gene expression in DO-F1 mice. Top10 Gen Ontology
(GO) of female (B) and male (C) differential expression
genes (DEGs) identified in enrichment analysis.
Pathways are ordered from top to bottom by
significance and colored by gene richness.

CONCLUSION REFERENCES ACKNOWLEDGEMENT

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males and females should be distinguished as Nat Commun 10, 2631. Contact Information
individual model organisms in biological Bennett, B.J., et al. (2015). Genetic Architecture
research, and why females are more susceptible of Atherosclerosis in Mice: A Systems Genetics Email: kmskim@ucdavis.edu
to atherosclerosis than males in the Analysis of Common Inbred Strains. PLOS
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