Effect of insulin-resistance on circulating and adipose tissue MMP-2 and MMP-9 activity in rats fed a sucrose-rich diet.

MIKSZTOWICZ V; MORALES C; ZAGO V; FRIEDMAN S; SCHREIER L; BERG G

NUTRITION METABOLISM AND CARDIOVASCULAR DISEASES

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2014 vol. 24 p. 294 - 300

0939-4753

Abstract Background and aim: Adipose tissue produces different metalloproteinases (MMPs),involved in adipogenesis and angiogenesis. Different studies have shown that in obesity thebehavior of different MMPs may be altered. However there are scarce data about the effect ofinsulin-resistance (IR) on MMP-2 and MMP-9 activity in adipose tissue. Our aim was to determinewhether sucrose induced IR modifies MMP-2 and MMP-9 behavior in expanded visceraladipose tissue and the contribution of this tissue to circulating activity of these gelatinases.Methods and results: Male Wistar rats were fed with standard diet (Control) or standard diet plus30% sucrose in the drinking water throughout 12 weeks (SRD). In epididymal adipose tissuevascular density, size and adipocyte density, PPARg expression and MMP-2 and -9 weremeasured. Adipose tissue from SRD presented higher adipocyte size (6.32 8.71 vs4.33 2.17 103 mm2, p Z 0.001) lower adipocyte density (164 (130e173) vs 190 (170e225)number/mm2, pZ0.046) and lower vascular density (16.2 (12.8e23.5) vs 28.1 (22.3e46.5) bloodvessels/mm2, p Z 0.002) than Control. MMP-2 and MMP-9 activity was decreased in SRD(1.93 0.7 vs 3.92 0.9 relative units, p Z 0.048 and 1.80 0.8 vs 5.13 1.7 relative units,p Z 0.004 respectively) in accordance with lower protein expression (0.35 0.20 vs2.71 0.48 relative units, p Z 0.004 and 1.12 0.21 vs 1.52 0.05 relative units, p Z 0.036respectively). There were no differences in PPARg expression between groups.Conclusion: Insulin resistance induced by SRD decreases MMP-2 and MMP-9 activity in adiposetissue which would not represent an important source for circulating MMP-2 and -9. In this stateof IR, PPARg would not be involved in the negative regulation of adipose tissue gelatinases.