Blood pressure, heart rate, and rate-pressure product in WT and D3KO.

<p><b>A.</b> Systolic blood pressure is stable in WT from 2 mo to 1 yr, but significantly increases from 1 yr to 2 yr (p<0.001, ANOVA). D3KO show similar values to 2 yr old WT. <b>B.</b> Diastolic blood pressure increases gradually with age in WT and reaches its peak at 2 years of age. D3KO show levels comparable to those of the 2 yr old WT and significantly higher than 2 mo or 1 yr old WT (p<0.001, ANOVA). <b>C.</b> Mean arterial pressure (MAP) increases gradually with age in WT and reaches its peak at 2 years of age. D3KO show levels comparable to those of the 2 yr old WT and significantly higher than 2 mo or 1 yr old WT (p<0.001, ANOVA). <b>D.</b> Heart rate reaches a peak in 1 yr old WT and drops significantly in the 2 yr old WT, and values are similar between 2 yr old WT and 2 mo old D3KO. <b>E.</b> The rate-pressure product increases with age in WT and is similar between 2 yr old WT and 2 mo old D3KO.</p

Changes in heart function with age.

<p><b>A.</b> In WT, ejection fraction decreases with age and is significantly reduced in 2 yr old WT compared to 2 mo. Ejection fraction in D3KO is significantly reduced from age-matched WT and is comparable to that of the 2 yr old WT. <b>B.</b> In WT, fractional shortening decreases with age and is significantly reduced in the 2 yr old WT versus 2 mo old WT. Note that D3KO fractional shortening is significantly reduced from age-matched WT but similar to that of the 2 yr old WT. <b>C.</b> Stroke volume peaks in WT at 1 yr before returning at 2 yrs to similar values as in 2 mo old WT. In D3KO stroke volume is significantly decreased over age-matched WT controls. <b>D.</b> Similar to stroke volume, cardiac output in WT significantly increases from 2 mo to 1 year before declining at 2 yrs of age. In D3KO cardiac output is significantly reduced compared to 1 yr old WT (p<0.001, ANOVA), or when solely compared to age-matched WT controls (p = 0.04, t-test).</p

Echocardiogram analysis.

<p>Average values ±S.E.</p><p>♯  =  significant difference between 2 mo WT and 1 yr WT.</p><p>§ =  significant difference between 2 mo WT and 2 yrs WT.</p><p>€  =  significant difference between 2 mo WT and 2 mo D3KO.</p><p>  =  significant difference between 1 yr WT and 2 mo D3KO.</p><p>  =  significant difference between 2 yr WT and 2 mo D3KO.</p

Kaplan-Meier curve of survival for WT and D3KO animals.

<p>Two cohorts of male animals kept were maintained and expressed a differential survival profile. D3KO started to die prematurely at 7 months of age, and at 15 months of age, only 67% (10/15) D3KO mice survived while 100% (14/14) of the WT animals survived to this time point.</p

Animal weights.

<p>Average values ±S.E.</p><p>♯  =  significant difference between 2 mo WT and 1 yr WT.</p

Quantification of matrix metalloproteinase activities.

<p><b>A.</b> MMP-2: In WT, MMP-2 activity increased with age and was similar between age-matched WT and D3KO. <b>B.</b> MMP-9: as with MMP-2, MMP-9 activity increased with age in WT, but was significantly higher in young D3KO compared to WT hearts at any age (ANOVA).</p

Myocyte interstitial fibrosis with age.

<p>Representative images of the left ventricle myocardium of 2 mo old WT (<b>A</b>), 1 yr old WT (<b>B</b>), 2 yr old WT (<b>C</b>), and 2 mo old D3KO mice (<b>D</b>). Images show increased content and thickness of fibrillar collagen with age (arrows) in WT hearts and in young D3KO hearts.</p

Quantification of myocyte interstitial fibrosis with age.

<p>Levels of fibrosis gradually rise with age in the WT hearts and are significantly increased in the 2 yr old WT hearts compared to the 2 mo old WT. Fibrosis is also significantly increased in 2 mo old D3KO hearts over age-matched WT and similar to levels observed in the 2 yr old WT.</p

Quantification of Western blot analyses for collagen types-I, type-III, and type-IV, normalized to α-tubulin.

<p><b>A.</b> Collagen-type I: expression levels of immature (pro) and mature forms of collagen type-I increase significantly with age in WT hearts and are similar between 2 yr old WT and 2 mo old D3KO. <b>B.</b> Collagen type-III: expression levels of collagen type III were similar in young and old WT hearts and were not significantly different in D3KO. <b>C.</b> Collagen type-IV: as with collagen type-III, expression levels of collagen type-IV were similar in the hearts of young and old WT and D3KO.</p