The online version of this article (doi:10.1186/1475-2840-11-100) contains supplementary material, which is available to authorized users.
The authors declare that they have no competing interests.
NMM was involved in conception and design of the study, data collection, data analysis and interpretation, as well as drafting and editing the final document for publication. AML was involved in data analysis and interpretation, as well as drafting and editing the final document for publication. UFM was involved in conception and design of the study, data analysis and interpretation, as well as reviewing all parts of the final document for publication. GHP was involved in data collection, data analysis and interpretation. OMM and MMM were involved in data collection (molecular analysis), data analysis and interpretation. BDS was involved in conception and design of the study, data analysis and interpretation, as well as writing, drafting and editing the final document for publication. All authors read and approved the final manuscript.
Metabolic syndrome is characterized by insulin resistance, which is closely related to GLUT4 content in insulin-sensitive tissues. Thus, we evaluated the GLUT4 expression, insulin resistance and inflammation, characteristics of the metabolic syndrome, in an experimental model.
Spontaneously hypertensive neonate rats (18/group) were treated with monosodium glutamate (MetS) during 9 days, and compared with Wistar-Kyoto (C) and saline-treated SHR (H). Blood pressure (BP) and lipid levels, C-reactive protein (CRP), interleukin 6 (IL-6), TNF-α and adiponectin were evaluated. GLUT4 protein was analysed in the heart, white adipose tissue and gastrocnemius. Studies were performed at 3 (3-mo), 6 (6-mo) and 9 (9-mo) months of age.
MetS rats were more insulin resistant (p<0.001, all ages) and had higher BP (3-mo: p<0.001, 6-mo: p = 0.001, 9-mo: p = 0.015) as compared to C. At 6 months, CRP, IL-6 and TNF-α were higher (p<0.001, all comparisons) in MetS rats vs H, but adiponectin was lower in MetS at 9 months (MetS: 32 ± 2, H: 42 ± 2, C: 45 ± 2 pg/mL; p<0.001). GLUT4 protein was reduced in MetS as compared to C rats at 3, 6 and 9-mo, respectively (Heart: 54%, 50% and 57%; Gastrocnemius: 37%, 56% and 50%; Adipose tissue: 69%, 61% and 69%).
MSG-treated SHR presented all metabolic syndrome characteristics, as well as reduced GLUT4 content, which must play a key role in the impaired glycemic homeostasis of the metabolic syndrome.
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- GLUT4 content decreases along with insulin resistance and high levels of inflammatory markers in rats with metabolic syndrome
Natalia M Leguisamo
Alexandre M Lehnen
Ubiratan F Machado
Maristela M Okamoto
Melissa M Markoski
Graziela H Pinto
Beatriz D Schaan
- BioMed Central
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