Echocardiographic changes in rats with metabolic syndrome observedafter long-term cola beverage drinking

MILEI J.; OTERO-LOSADA, M.; GOMEZ-LLAMBI H.; GRANA D.; SUAREZ D.; AZZATO F; AMBROSIO G.

Lisboa

Congreso; 47th. Annual Meeting of the European Association for the Study of Diabetes (EASD); 2011

European Association for the Study of Diabetes (EASD)

Background and Aim: previously we reported metabolic syndrome-associated alterations in a cola-drinking rat model. Metabolic syndrome has been linked to increased risk of type II diabetes and cardiovascular disease. This work evaluates whether chronic drinking of cola beverages may affect cardiac geometry.Methods: 48 male Wistar rats drank regular cola beverage (C), light cola beverage (L) or tap water (W) ad libitum (n=16 per group). After 6 months (treatment) 50% of C6 , L6 and W6 rats were euthanized. Heart and thoracic and abdominal aorta were excised and harvested for light microscopy (histopathology) at the time of euthanasia. Echocardiograms (ATL 3000 HDI, Bethold, WA, USA) and systolic blood pressure (SBP) (tail cuff plethysmography, electro- sphygmomanometer PE-300. Physiograph MK-IIIS , Narco Bio-Systems, Austin, Texas) were recorded in awake rats at the beginning of the study (baseline) and after treatment (6 months). At the beginning of the study all three experimental groups were indistinguishable from each other according with variables of interest.Results: C6 and L6 groups were respectively different from W6 group based on: (I). Left ventricular diastolic dimension (LVDD, mm): 7.4±0.3 (+9%, mean diff.= 0.60, CI95%=1.10 to 0.10, t= 3.19, p<0.01) and 7.3±0.7 (+7%, mean diff.= 0.50, CI95%= 0.99 to 0.09, t= 2.71, p<0.05) vs. 6.8±0.4; (II). Left ventricular diastolic volume (LVDV, ml): 0.34±0.04 (+26%, mean diff.= +0.07, CI95%=0.13 to 0.01, t= 3.32, p<0.05) and 0.33±0.06 (+22%, mean diff.= +0.06, CI95%=0.12 to 0.01, t= 2.90, p<0.05) vs. 0.27±0.04; (III). Systolic volume (SV, ml): 0.31±0.04 (+24%, mean diff.= 0.60, CI95%= 0.12 to 0.01, t= 2.76, p<0.05) and 0.31±0.03 (+24%, mean diff.= 0.60, CI95%= 0.12 to 0.01, t= 2.80, p<0.05) vs. 0.25±0.04; (IV). Relative wall thickness (RWTh): 0.37±0.03 (-8%, mean diff.= 0.60, CI95%= 0.003 to 0.077, t= 2.90, p<0.05) and 0.36±0.05 (-10%, mean diff.= 0.60, CI95%= 0.004 to 0.076, t= 2.90, p<0.05)] vs. 0.40±0.03. C6 was different from W6 based on cardiac output (ml/min): 148±20 (+29%, mean diff.=+33, CI95%= 66.0 to 0.01, t= 3.06, p<0.05) vs. 115±21. Treatment had no effect on heart rate (bpm): 470±46 (C6), 457±44 (L6), 469±36 (W6). The necropsy findings were scarce and showed no relation to treatment.Conclusions: six months’ cola beverage drinking led to increases in diastolic and systolic volumes and left ventricle posterior wall thinning that resulted in larger cardiac output without affecting heart rate. Factors responsible for cardiac remodeling in long-term light cola drinking animals are to be identified.