Plasma matrix metalloproteinase (MMP)-9 levels are reduced following low-calorie cranberry juice supplementation in men.
OBJECTIVE
Matrix metalloproteinase (MMP)-9, also known as gelatinase B, is implicated in the development of hypertension and atherosclerotic plaque vulnerability to rupture, an important step in the etiology of cardiovascular diseases. Studies have suggested that flavonoid consumption may be cardioprotective, and its favorable impact on circulating MMP-9 concentrations could partly explain this association. The aim of the present study was to determine the effect of consuming increasing daily doses of low-calorie cranberry juice cocktail (CJC) on plasma MMP-9 concentrations of abdominally obese men.


METHODS
Thirty men (mean age +/- SD: 51 +/- 10 years) consumed increasing doses of CJC during 3 successive periods of 4 weeks (weeks 1-4: 125 ml/day, weeks 5-8: 250 ml/day, and weeks 9-12: 500 ml/day). Before the study and after each phase, a series of physical and metabolic variables were measured, including MMP-9.


RESULTS
We found that CJC supplementation significantly decreased plasma MMP-9 concentrations (mean +/- SEM: -36% +/- 9%, p < 0.0005; week 12 vs. baseline) while baseline plasma MMP-9 concentrations strongly correlated with the changes noted over the entire intervention (r = -0.71, p < 0.0001). We also show that the reduction in plasma MMP-9 levels was associated with a change in plasma nitrites/nitrates (NOx) concentration over the entire intervention (r = -0.38, p < 0.05; week 12 vs. baseline). Significant correlations were also noted between changes in plasma MMP-9 levels and those of systolic (r = 0.39, p < 0.05) and diastolic (r = 0.60, p < 0.001) blood pressure during the course of the study (week 12 vs. baseline).


CONCLUSIONS
Our results show that daily CJC consumption is associated with a decrease in plasma MMP-9 concentrations in abdominally obese men. We hypothesize that polyphenolic compounds from cranberries may be responsible for this effect, supporting the notion that the consumption of flavonoid-rich foods can exert cardioprotective effects.
Institute of Nutraceuticals and Functional Foods, Laval University Research Center, Québec, CHUL Pavilion, Québec G1V 0A6, CANADA,
Guillaume
G
Ruel
Sonia
S
Pomerleau
Patrick
P
Couture
Simone
S
Lemieux
Benoît
B
Lamarche
Charles
C
Couillard
D000328:Adult; D001628:Beverages; D001794:Blood Pressure; D019587:Dietary Supplements; D002149:Energy Intake; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D016896:Treatment Outcome; D029799:Vaccinium macrocarpon
D020780:Matrix Metalloproteinase 9