Article

Adiponectin receptors gene expression and insulin sensitivity in non-diabetic Mexican Americans with or without a family history of Type 2 diabetes.

Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
Diabetologia (impact factor: 6.81). 06/2004; 47(5):816-20. DOI:10.1007/s00125-004-1359-x pp.816-20
Source: PubMed

ABSTRACT The recent discovery of two adiponectin receptors (AdipoR1 and AdipoR2) will improve our understanding of the molecular mechanisms underlying the insulin-sensitising effect of adiponectin. The aim of this study was to determine for the first time whether skeletal muscle AdipoR1 and/or AdipoR2 gene expression levels are associated with insulin resistance.
Using RT-PCR and northern analysis we measured AdipoR1 and AdipoR2 gene expression in skeletal muscle from healthy Mexican Americans with normal glucose tolerance who had (n=8) or did not have (n=10) a family history of Type 2 diabetes.
Gene expression profiling indicated that the AdipoR1 and AdipoR2 isoforms are highly expressed in human skeletal muscle, unlike in mice where AdipoR2 expression was highest in the liver, and AdipoR1 was highest in skeletal muscle. In the study subjects, the expression levels of AdipoR1 (p=0.004) and AdipoR2 (p=0.04), as well as plasma adiponectin concentration (p=0.03) were lower in people with a family history of Type 2 diabetes than in those with no family history of the disease. Importantly, the expression levels of both receptors correlated positively with insulin sensitivity (r=0.64, p=0.004 and r=0.47, p=0.048 respectively).
Collectively, these data indicate that both isoforms of the adiponectin receptor play a role in the insulin-sensitising effect of adiponectin.

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Keywords

adiponectin receptor
 
adiponectin receptors
 
AdipoR2 expression
 
AdipoR2 gene expression
 
AdipoR2 gene expression levels
 
AdipoR2 isoforms
 
Gene expression profiling
 
healthy Mexican Americans
 
human skeletal muscle
 
insulin resistance
 
insulin sensitivity
 
insulin-sensitising effect
 
normal glucose tolerance
 
northern analysis
 
plasma adiponectin concentration
 
recent discovery
 
receptors correlated
 
skeletal muscle AdipoR1
 
study subjects
 
Type 2 diabetes