Blockade of kinin B(1)  receptor reverses plasma fatty acids composition changes and body and tissue fat gain in a rat model of insulin resistance.
OBJECTIVE
Kinin B(1) receptor (B(1) R) contributes to insulin resistance through a mechanism involving oxidative stress. This study examined the effect of B(1) R blockade on the changes in plasma fatty acids composition, body and tissue fat mass and adipose tissue inflammation that influence insulin resistance.


METHODS
Sprague-Dawley rats were fed with 10% D-glucose or tap water (Control) for 13 weeks and during the last week, rats were administered the B(1) R antagonist SSR240612 (10 mg/kg/day, gavage) or vehicle. The following parameters were assessed: plasma fatty acids (by gas chromatography), body composition (by EchoMRI), metabolic hormone levels (by radioimmunoassay), expression of B(1) R and inflammatory markers in adipose tissue (by Western blot and qRT-PCR).


RESULTS
Glucose feeding significantly increased plasma levels of glucose, insulin, leptin, palmitoleic acid (16:1n-7), oleic acid (18:1n-9), Δ6 and Δ9 desaturases while linoleic acid (18:2n-6), arachidonic acid (20:4n-6) and Δ5 desaturase were decreased. SSR240612 reduced plasma levels of insulin, glucose, the homeostasis model assessment index of insulin resistance, palmitoleic acid and n-7 family. Alterations of Δ5, Δ6 and Δ9 desaturases were normalized by SSR240612. The B(1) R antagonist also reversed the enhancing effect of glucose feeding on whole body and epididymal fat mass and on the expression of macrophage CD68, interleukin-1β, tumour necrosis factor-α and inducible nitric oxide synthase in retroperitoneal adipose tissue. B(1) R protein and mRNA were not detected in retroperitoneal adipose tissue.


CONCLUSIONS
Insulin resistance in glucose-fed rats is associated with low state inflammation in adipose tissue and plasma fatty acids changes which are reversed by B(1) R blockade. These beneficial effects may contribute to insulin sensitivity improvement and the prevention of obesity.
Department of Physiology, Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada.
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Dias
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Couture
D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D065169:Bradykinin B1 Receptor Antagonists; D004149:Dioxoles / Q000008:administration & dosage / Q000494:pharmacology*; D004195:Disease Models, Animal; D005227:Fatty Acids / Q000097:blood*; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology*; D007249:Inflammation / Q000378:metabolism; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D043783:Receptor, Bradykinin B1 / Q000378:metabolism; D013449:Sulfonamides / Q000008:administration & dosage / Q000494:pharmacology*
C487113:2-((3-(1,3-benzodioxol-5-yl)-3-(((6-methoxy-2-naphthyl)sulfonyl)amino)propanoyl)amino)-3-(4-((2,6-dimethylpiperidinyl)methyl)phenyl)-N-isopropyl-N-methylpropanamide; D001786:Blood Glucose; D065169:Bradykinin B1 Receptor Antagonists; D004149:Dioxoles; D005227:Fatty Acids; D043783:Receptor, Bradykinin B1; D013449:Sulfonamides; D005947:Glucose