Dataset Information

Ectopic fat accumulation and distant organ-specific insulin resistance in Japanese people with nonalcoholic fatty liver disease.

ABSTRACT:

Objective

The aim of this study was to examine the association between ectopic fat and organ-specific insulin resistance (IR) in insulin-target organs in patients with nonalcoholic fatty liver disease (NAFLD).

Methods

Organ-specific IR in the liver (hepatic glucose production (HGP) × fasting plasma insulin (FPI) and suppression of HGP by insulin [%HGP]), skeletal muscle (insulin-stimulated glucose disposal [Rd]), and adipose tissue (suppression of FFA by insulin [%FFA]) was measured in 69 patients with NAFLD using a euglycemic hyperinsulinemic clamp with tracer infusion ([6,6-2H2]glucose). Liver fat, intramyocellular lipid (IMCL), and body composition were measured by liver biopsy, proton magnetic resonance spectroscopy, and bioelectrical impedance analysis, respectively.

Results

HGP × FPI was significantly correlated with Rd (r = ?-0.57, P<0.001), %HGP with %FFA (r = 0.38, P<0.01), and Rd with %FFA (r = 0.27, P<0.05). Liver steatosis score was negatively associated with Rd (r =? -0.47, P<0.001) as well as with HGP × FPI (r = 0.43, P<0.001). Similarly, intrahepatic lipid was negatively associated with Rd (r =? -0.32, P<0.05). IMCL was not associated with Rd (r =? -0.16, P = 0.26). Fat mass and its percentage were associated with HGP × FPI (r = 0.50, P<0.001; r = 0.48, P<0.001, respectively) and Rd (r =? -0.59, P<0.001; r =? -0.52, P<0.001, respectively), but not with %FFA (r = ?-0.21, P = 0.10; r = ?-0.001, P = 0.99, respectively).

Conclusion

Unexpectedly, fat accumulation in the skeletal muscle and adipose tissue was not associated with organ-specific IR. Instead, liver fat was associated not only with hepatic IR but also with skeletal muscle IR, suggesting a central role of fatty liver in systemic IR and that a network exists between liver and skeletal muscle.

SUBMITTER: Kato K

PROVIDER: S-EPMC3961287 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Publications

Ectopic fat accumulation and distant organ-specific insulin resistance in Japanese people with nonalcoholic fatty liver disease.

Kato Ken-ichiro K Takamura Toshinari T Takeshita Yumie Y Ryu Yasuji Y Misu Hirofumi H Ota Tsuguhito T Tokuyama Kumpei K Nagasaka Shoichiro S Matsuhisa Munehide M Matsui Osamu O Kaneko Shuichi S

PloS one 20140320 3

<h4>Objective</h4>The aim of this study was to examine the association between ectopic fat and organ-specific insulin resistance (IR) in insulin-target organs in patients with nonalcoholic fatty liver disease (NAFLD).<h4>Methods</h4>Organ-specific IR in the liver (hepatic glucose production (HGP) × fasting plasma insulin (FPI) and suppression of HGP by insulin [%HGP]), skeletal muscle (insulin-stimulated glucose disposal [Rd]), and adipose tissue (suppression of FFA by insulin [%FFA]) was measur ...[more]

PMID: 24651470

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Dataset Information

Ectopic fat accumulation and distant organ-specific insulin resistance in Japanese people with nonalcoholic fatty liver disease.

Objective

Methods

Results

Conclusion

Publications

Ectopic fat accumulation and distant organ-specific insulin resistance in Japanese people with nonalcoholic fatty liver disease.

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