Limits...
The genetic architecture of NAFLD among inbred strains of mice.

Hui ST, Parks BW, Org E, Norheim F, Che N, Pan C, Castellani LW, Charugundla S, Dirks DL, Psychogios N, Neuhaus I, Gerszten RE, Kirchgessner T, Gargalovic PS, Lusis AJ - Elife (2015)

Bottom Line: Genome-wide association studies revealed three loci associated with hepatic TG accumulation.We hypothesize that Gde1 expression increases TG production by contributing to the production of glycerol-3-phosphate.Our multi-level data, including transcript levels, metabolite levels, and gut microbiota composition, provide a framework for understanding genetic and environmental interactions underlying hepatic steatosis.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.

ABSTRACT
To identify genetic and environmental factors contributing to the pathogenesis of non-alcoholic fatty liver disease, we examined liver steatosis and related clinical and molecular traits in more than 100 unique inbred mouse strains, which were fed a diet rich in fat and carbohydrates. A >30-fold variation in hepatic TG accumulation was observed among the strains. Genome-wide association studies revealed three loci associated with hepatic TG accumulation. Utilizing transcriptomic data from the liver and adipose tissue, we identified several high-confidence candidate genes for hepatic steatosis, including Gde1, a glycerophosphodiester phosphodiesterase not previously implicated in triglyceride metabolism. We confirmed the role of Gde1 by in vivo hepatic over-expression and shRNA knockdown studies. We hypothesize that Gde1 expression increases TG production by contributing to the production of glycerol-3-phosphate. Our multi-level data, including transcript levels, metabolite levels, and gut microbiota composition, provide a framework for understanding genetic and environmental interactions underlying hepatic steatosis.

No MeSH data available.


Related in: MedlinePlus

Correlation of hepatic TG content with plasma metabolites and HOMA-IR.(A–F) Correlation of hepatic TG with plasma TG (A), plasma cholesterol (B), plasma glycerol (C), plasma insulin (D), plasma glucose (E), and HOMA-IR (F). r, biweight midcorrelation; p, p-value.DOI:http://dx.doi.org/10.7554/eLife.05607.005
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493743&req=5

fig3: Correlation of hepatic TG content with plasma metabolites and HOMA-IR.(A–F) Correlation of hepatic TG with plasma TG (A), plasma cholesterol (B), plasma glycerol (C), plasma insulin (D), plasma glucose (E), and HOMA-IR (F). r, biweight midcorrelation; p, p-value.DOI:http://dx.doi.org/10.7554/eLife.05607.005

Mentions: A substantial amount of hepatic TG is derived from FAs of extrahepatic sources, in particular, the white adipose tissue. We measured lipid and metabolites in the plasma and compared them to the hepatic TG content. Hepatic TG content was poorly correlated with plasma TG levels (r = −0.13, p = 0.0115, Figure 3A), whereas it was positively correlated with plasma cholesterol levels (r = 0.41, p = 5.04 × 10−17, Figure 3B). The correlation between hepatic TG levels and plasma free FAs (FFAs) levels was not significant (r = 0.04, p = 0.44); however, hepatic TG levels were correlated with plasma glycerol levels (r = 0.20, p = 0.0001, Figure 3C), suggesting a link between liver steatosis and lipolysis in the adipose tissue. NAFLD is often associated with dyslipidemia (Diehl et al., 1988) and insulin resistance (Marchesini et al., 1999) in humans. Similar to the findings in humans, there was a robust association between hepatic steatosis and plasma insulin (r = 0.47, p = 4.51 × 10−21, Figure 3D), glucose (r = 0.23, p = 1.26 × 10−5, Figure 3E) as well as insulin resistance (HOMA-IR) (r = 0.45, p = 2.18 × 10−20, Figure 3F).10.7554/eLife.05607.005Figure 3.Correlation of hepatic TG content with plasma metabolites and HOMA-IR.


The genetic architecture of NAFLD among inbred strains of mice.

Hui ST, Parks BW, Org E, Norheim F, Che N, Pan C, Castellani LW, Charugundla S, Dirks DL, Psychogios N, Neuhaus I, Gerszten RE, Kirchgessner T, Gargalovic PS, Lusis AJ - Elife (2015)

Correlation of hepatic TG content with plasma metabolites and HOMA-IR.(A–F) Correlation of hepatic TG with plasma TG (A), plasma cholesterol (B), plasma glycerol (C), plasma insulin (D), plasma glucose (E), and HOMA-IR (F). r, biweight midcorrelation; p, p-value.DOI:http://dx.doi.org/10.7554/eLife.05607.005
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493743&req=5

fig3: Correlation of hepatic TG content with plasma metabolites and HOMA-IR.(A–F) Correlation of hepatic TG with plasma TG (A), plasma cholesterol (B), plasma glycerol (C), plasma insulin (D), plasma glucose (E), and HOMA-IR (F). r, biweight midcorrelation; p, p-value.DOI:http://dx.doi.org/10.7554/eLife.05607.005
Mentions: A substantial amount of hepatic TG is derived from FAs of extrahepatic sources, in particular, the white adipose tissue. We measured lipid and metabolites in the plasma and compared them to the hepatic TG content. Hepatic TG content was poorly correlated with plasma TG levels (r = −0.13, p = 0.0115, Figure 3A), whereas it was positively correlated with plasma cholesterol levels (r = 0.41, p = 5.04 × 10−17, Figure 3B). The correlation between hepatic TG levels and plasma free FAs (FFAs) levels was not significant (r = 0.04, p = 0.44); however, hepatic TG levels were correlated with plasma glycerol levels (r = 0.20, p = 0.0001, Figure 3C), suggesting a link between liver steatosis and lipolysis in the adipose tissue. NAFLD is often associated with dyslipidemia (Diehl et al., 1988) and insulin resistance (Marchesini et al., 1999) in humans. Similar to the findings in humans, there was a robust association between hepatic steatosis and plasma insulin (r = 0.47, p = 4.51 × 10−21, Figure 3D), glucose (r = 0.23, p = 1.26 × 10−5, Figure 3E) as well as insulin resistance (HOMA-IR) (r = 0.45, p = 2.18 × 10−20, Figure 3F).10.7554/eLife.05607.005Figure 3.Correlation of hepatic TG content with plasma metabolites and HOMA-IR.

Bottom Line: Genome-wide association studies revealed three loci associated with hepatic TG accumulation.We hypothesize that Gde1 expression increases TG production by contributing to the production of glycerol-3-phosphate.Our multi-level data, including transcript levels, metabolite levels, and gut microbiota composition, provide a framework for understanding genetic and environmental interactions underlying hepatic steatosis.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.

ABSTRACT
To identify genetic and environmental factors contributing to the pathogenesis of non-alcoholic fatty liver disease, we examined liver steatosis and related clinical and molecular traits in more than 100 unique inbred mouse strains, which were fed a diet rich in fat and carbohydrates. A >30-fold variation in hepatic TG accumulation was observed among the strains. Genome-wide association studies revealed three loci associated with hepatic TG accumulation. Utilizing transcriptomic data from the liver and adipose tissue, we identified several high-confidence candidate genes for hepatic steatosis, including Gde1, a glycerophosphodiester phosphodiesterase not previously implicated in triglyceride metabolism. We confirmed the role of Gde1 by in vivo hepatic over-expression and shRNA knockdown studies. We hypothesize that Gde1 expression increases TG production by contributing to the production of glycerol-3-phosphate. Our multi-level data, including transcript levels, metabolite levels, and gut microbiota composition, provide a framework for understanding genetic and environmental interactions underlying hepatic steatosis.

No MeSH data available.


Related in: MedlinePlus