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AICAR Protects against High Palmitate/High Insulin-Induced Intramyocellular Lipid Accumulation and Insulin Resistance in HL-1 Cardiac Cells by Inducing PPAR-Target Gene Expression.

Rodríguez-Calvo R, Vázquez-Carrera M, Masana L, Neumann D - PPAR Res (2015)

Bottom Line: Treatment with AICAR induced gene expression of all three PPARs, but only the Ppara and Pparg regulation were dependent on AMPK.AICAR treatment induced the expression of Acadvl and Glut4, which correlated to prevention of the HP/HI-induced intramyocellular lipid build-up, and attenuation of the HP/HI-induced impairment of glucose uptake.These data support the hypothesis that AICAR contributes to cardiac metabolic adaptation via regulation of transcriptional mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Genetics, CARIM School for Cardiovascular Diseases, Faculty of Health, Medicine and Life Sciences, Maastricht University, 6200 MD Maastricht, Netherlands.

ABSTRACT
Here we studied the impact of 5-aminoimidazole-4-carboxamide riboside (AICAR), a well-known AMPK activator, on cardiac metabolic adaptation. AMPK activation by AICAR was confirmed by increased phospho-Thr(172)-AMPK and phospho-Ser(79)-ACC protein levels in HL-1 cardiomyocytes. Then, cells were exposed to AICAR stimulation for 24 h in the presence or absence of the AMPK inhibitor Compound C, and the mRNA levels of the three PPARs were analyzed by real-time RT-PCR. Treatment with AICAR induced gene expression of all three PPARs, but only the Ppara and Pparg regulation were dependent on AMPK. Next, we exposed HL-1 cells to high palmitate/high insulin (HP/HI) conditions either in presence or in absence of AICAR, and we evaluated the expression of selected PPAR-targets genes. HP/HI induced insulin resistance and lipid storage was accompanied by increased Cd36, Acot1, and Ucp3 mRNA levels. AICAR treatment induced the expression of Acadvl and Glut4, which correlated to prevention of the HP/HI-induced intramyocellular lipid build-up, and attenuation of the HP/HI-induced impairment of glucose uptake. These data support the hypothesis that AICAR contributes to cardiac metabolic adaptation via regulation of transcriptional mechanisms.

No MeSH data available.


Related in: MedlinePlus

AICAR prevents the HP/HI-induced intramyocellular lipid accumulation in HL-1. Lipid content was analyzed by Oil-Red-O staining in HL-1 challenged with HP/HI for 16 h in the presence or absence of AICAR (24 h). (a) Representative microphotography showing lipid droplets in cells counterstained with Haematoxylin (bar 20 μm). Squares indicate the areas shown at high magnification. (b) Quantification of stained areas relative to cell surface. Data are expressed as mean ± SD of 5 different pictures from 3 independent experiments (∗∗P < 0.01 versus control nonstimulated cells; #P < 0.05 versus HP/HI-stimulated cells).
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fig4: AICAR prevents the HP/HI-induced intramyocellular lipid accumulation in HL-1. Lipid content was analyzed by Oil-Red-O staining in HL-1 challenged with HP/HI for 16 h in the presence or absence of AICAR (24 h). (a) Representative microphotography showing lipid droplets in cells counterstained with Haematoxylin (bar 20 μm). Squares indicate the areas shown at high magnification. (b) Quantification of stained areas relative to cell surface. Data are expressed as mean ± SD of 5 different pictures from 3 independent experiments (∗∗P < 0.01 versus control nonstimulated cells; #P < 0.05 versus HP/HI-stimulated cells).

Mentions: In order to explore whether AICAR-induced Acadvl expression was related to changes in the intramyocellular lipid content, we performed Oil-Red-O staining in HL-1 cells challenged with HP/HI. HP/HI increased the lipid accumulation (~4.6-fold; P < 0.01 versus CT) compared to nonstimulated cells. However, AICAR treatment prevented the effect of HP/HI on intramyocellular lipid accumulation (Figures 4(a) and 4(b)).


AICAR Protects against High Palmitate/High Insulin-Induced Intramyocellular Lipid Accumulation and Insulin Resistance in HL-1 Cardiac Cells by Inducing PPAR-Target Gene Expression.

Rodríguez-Calvo R, Vázquez-Carrera M, Masana L, Neumann D - PPAR Res (2015)

AICAR prevents the HP/HI-induced intramyocellular lipid accumulation in HL-1. Lipid content was analyzed by Oil-Red-O staining in HL-1 challenged with HP/HI for 16 h in the presence or absence of AICAR (24 h). (a) Representative microphotography showing lipid droplets in cells counterstained with Haematoxylin (bar 20 μm). Squares indicate the areas shown at high magnification. (b) Quantification of stained areas relative to cell surface. Data are expressed as mean ± SD of 5 different pictures from 3 independent experiments (∗∗P < 0.01 versus control nonstimulated cells; #P < 0.05 versus HP/HI-stimulated cells).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4663352&req=5

fig4: AICAR prevents the HP/HI-induced intramyocellular lipid accumulation in HL-1. Lipid content was analyzed by Oil-Red-O staining in HL-1 challenged with HP/HI for 16 h in the presence or absence of AICAR (24 h). (a) Representative microphotography showing lipid droplets in cells counterstained with Haematoxylin (bar 20 μm). Squares indicate the areas shown at high magnification. (b) Quantification of stained areas relative to cell surface. Data are expressed as mean ± SD of 5 different pictures from 3 independent experiments (∗∗P < 0.01 versus control nonstimulated cells; #P < 0.05 versus HP/HI-stimulated cells).
Mentions: In order to explore whether AICAR-induced Acadvl expression was related to changes in the intramyocellular lipid content, we performed Oil-Red-O staining in HL-1 cells challenged with HP/HI. HP/HI increased the lipid accumulation (~4.6-fold; P < 0.01 versus CT) compared to nonstimulated cells. However, AICAR treatment prevented the effect of HP/HI on intramyocellular lipid accumulation (Figures 4(a) and 4(b)).

Bottom Line: Treatment with AICAR induced gene expression of all three PPARs, but only the Ppara and Pparg regulation were dependent on AMPK.AICAR treatment induced the expression of Acadvl and Glut4, which correlated to prevention of the HP/HI-induced intramyocellular lipid build-up, and attenuation of the HP/HI-induced impairment of glucose uptake.These data support the hypothesis that AICAR contributes to cardiac metabolic adaptation via regulation of transcriptional mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Genetics, CARIM School for Cardiovascular Diseases, Faculty of Health, Medicine and Life Sciences, Maastricht University, 6200 MD Maastricht, Netherlands.

ABSTRACT
Here we studied the impact of 5-aminoimidazole-4-carboxamide riboside (AICAR), a well-known AMPK activator, on cardiac metabolic adaptation. AMPK activation by AICAR was confirmed by increased phospho-Thr(172)-AMPK and phospho-Ser(79)-ACC protein levels in HL-1 cardiomyocytes. Then, cells were exposed to AICAR stimulation for 24 h in the presence or absence of the AMPK inhibitor Compound C, and the mRNA levels of the three PPARs were analyzed by real-time RT-PCR. Treatment with AICAR induced gene expression of all three PPARs, but only the Ppara and Pparg regulation were dependent on AMPK. Next, we exposed HL-1 cells to high palmitate/high insulin (HP/HI) conditions either in presence or in absence of AICAR, and we evaluated the expression of selected PPAR-targets genes. HP/HI induced insulin resistance and lipid storage was accompanied by increased Cd36, Acot1, and Ucp3 mRNA levels. AICAR treatment induced the expression of Acadvl and Glut4, which correlated to prevention of the HP/HI-induced intramyocellular lipid build-up, and attenuation of the HP/HI-induced impairment of glucose uptake. These data support the hypothesis that AICAR contributes to cardiac metabolic adaptation via regulation of transcriptional mechanisms.

No MeSH data available.


Related in: MedlinePlus