Matrix metalloproteinase-1 and -2 levels are differently regulated in acute exacerbation of heart failure in patients with and without left ventricular systolic dysfunction

Matrix metalloproteinases (MMPs) play important roles in progression of chronic heart failure (HF) by regulating cardiac extracellular matrix metabolism. However, there is no report to investigate the difference of circulating MMP-1 and MMP-2 levels between systolic HF (SHF) and diastolic HF (DHF), particularly in light of acute exacerbation of HF. We assessed 110 HF patients who were admitted because of an acute exacerbation. They were divided into two groups: SHF [n = 68, left ventricular ejection fraction (LVEF) <45%] or DHF (n = 42, LVEF ≥45%). Ten patients without HF served as controls. Serum MMP-1 and MMP-2, and plasma brain natriuretic peptide (BNP) levels were examined on admission and at discharge. Serum MMP-1 level was higher on admission in both SHF and DHF than in controls. It was higher in SHF than in DHF and did not change at discharge in both groups. Serum MMP-2 level was equally higher on admission in SHF and DHF than in controls. It decreased in both groups at discharge. Treatment-induced changes in LVEF and BNP level correlated with those in MMP-2 level in SHF but not in DHF. Circulating MMP-1 and MMP-2 levels showed different dynamics between SHF and DHF in acute exacerbation and after treatment. These differences in circulating MMP-1 and MMP-2 levels may be related to the phenotype of HF.     

Plasma tissue inhibitor of metalloproteinase-1 levels are elevated in essential hypertension and related to left ventricular hypertrophy

BACKGROUND: Essential hypertensive patients have an increased heart and arterial collagen concentration. Increased collagen synthesis can be assessed using procollagen III N peptide (PIIINP) and reduced collagen degradation measured using tissue inhibitor of metalloproteinase-1 (TIMP-1). METHODS: Plasma TIMP-1 and PIIINP levels were measured in 31 patients with essential hypertension and in 17 normotensive control subjects. The hypertensive patients were either treatment naive (n = 18) or had been without treatment for 1 month (n = 13). Both groups of patients were screened to exclude other fibrotic diseases. RESULTS: In the hypertensive patients, TIMP-1 levels were significantly (P < .0002) elevated (median 380 ng/ mL, range 160 to 1,560 ng/mL) compared with those of the normotensive control subjects (median 178 ng/mL, range 99 to 330 ng/mL). In hypertensive subjects who had never received antihypertensive therapy there were significant correlations between TIMP-1 and left ventricular posterior wall thickness in diastole (LVPWd) (r = 0.58) (P < .02) and left ventricular mass index (r = 0.58) (P < .02). There was no difference in PIIINP levels (mean +/- 2 SD) between the hypertensive (0.56 U/mL +/- 0.3) and normotensive groups (0.52 U/mL +/- 0.2). CONCLUSIONS: The increased tissue collagen III levels found in the heart and vessels of hypertensive patients is due to a reduction in collagen degradation because of high TIMP-1 levels, rather than an increase in synthesis of collagen type III. The tissue source of this TIMP-1 is unclear.     

MMP/TIMP expression in spontaneously hypertensive heart failure rats: the effect of ACE- and MMP-inhibition

OBJECTIVE: Determine the effect of a matrix metalloproteinase inhibitor (MMPi) and angiotensin converting enzyme inhibitor (ACEi) on collagen, MMP, tissue inhibitors of MMPs (TIMPs) expression in the spontaneously hypertensive heart failure (SHHF) rat. METHODS: Six groups were tested: normotensive 9- and 13-month-old Wistar-Furth (WF) rats, 9-month-old SHHFs (compensatory hypertrophy), 13-month-old SHHFs with HF, and 13-month-old SHHFs orally administered with either an MMPi (PD166793, 5 mgkg(-1)day(-1)) or ACEi (quinapril, 10 mgkg(-1)day(-1)) for 4 months. Collagen volume fraction was assessed histomorphometrically. Left ventricular (LV) mRNA [MMP-1,-2,-3,-7,-9,-11,-13,-14; TIMP-1,-2,-3,-4; and collagen alpha1(I) and alpha1(III)] and protein (MMP-2 and MMP-9 zymographic activity; Western blot analysis of MMP-13, and TIMP-1,-2,-4) levels could be quantified. RESULTS: Collagen mRNA levels were elevated in SHHFs compared to age-matched controls, but collagen volume fraction was elevated only in 13-month-old SHHFs (approximately 2x). Only MMP-2 mRNA levels increased significantly with HF. However, MMP-2 and MMP-9 zymographic activity, and MMP-13 protein levels increased. TIMP-1 and TIMP-2 mRNA and protein levels increased, and TIMP-4 protein levels decreased in SHHFs vs. controls. Both drug treatments reduced LV dilation; preserved systolic function; and normalized MMP/TIMP expression. Both drug treatments also reduced collagen volume fraction, but only quinapril reduced collagen mRNA levels and LV hypertrophy. CONCLUSIONS: The divergent effect of MMPi and ACEi on collagen mRNA levels and hypertrophy indicate that drug efficacy is mediated by different pathways in the SHHF rat.     

Autonomic function in elderly patients with chronic heart failure

AIMS: Autonomic function (AF) is attenuated by heart failure (HF). Reports have been based on studies of young patients with systolic heart failure (SHF). However, HF is a disease of older patients who are more likely to have diastolic heart failure (DHF). We investigated whether age alters AF in elderly HF patients and whether the haemodynamic type of HF influences AF. METHOD AND RESULTS: Thirty-six elderly HF (Framingham criteria) patients (11 with SHF, 25 with DHF) and 21 matched healthy subjects underwent simple bedside AF tests. Compared with the reference values for healthy adults, the mean E:I ratios and the median 30:15 ratios standing were all essentially normal. The median 30:15 ratios tilt and the mean Valsalva ratios were all significantly below the reference value (P for all cases <0.050). Comparing three groups, there were no significant differences for mean E:I ratio (P=0.111), 30:15 tilt (P=0.619) and 30:15 standing (P=0.167), whereas there were significant differences for the mean Valsalva ratios (P=0.001). The mean Valsalva ratio of the SHF patients was significantly lower than that for the DHF patients (P<0.001) which in turn was significantly lower than the result of the healthy subjects (P<0.001). CONCLUSION: There is an age-related impairment in AF with further impairment occurring in patients with HF. However, the severity of autonomic dysfunction is less in patients with DHF compared with patients with SHF.     

B-type natriuretic peptide strongly reflects diastolic wall stress in patients with chronic heart failure: comparison between systolic and diastolic heart failure.

OBJECTIVES: We explored the stimulus for B-type natriuretic peptide (BNP) secretion in the clinical setting of heart failure (HF). BACKGROUND: Increasingly, plasma BNP levels are being incorporated into the clinical assessment and management of systolic heart failure (SHF) as well as diastolic heart failure (DHF). However, heterogeneity in BNP levels among individuals with HF can cause some confusion in interpreting results. METHODS: In 160 consecutive patients presenting with HF, we measured plasma BNP levels and performed echocardiography and cardiac catheterization. Systolic and diastolic meridional wall stress was calculated from echocardiographic and hemodynamic data. RESULTS: Although plasma BNP had a significant correlation (r2 = 0.296 [p < 0.001]) with left ventricular end-diastolic pressure (EDP) as previously reported, the correlation between plasma BNP and end-diastolic wall stress (EDWS) (r2 = 0.887 [p < 0.001]) was more robust. In a subanalysis of 62 patients with DHF, a similar result was obtained (r2 = 0.143 for EDP and r2 = 0.704 for EDWS). In a comparison between SHF and DHF, the BNP level was significantly higher in SHF (p < 0.001). Although EDP did not show any difference, EDWS was significantly higher in SHF than in DHF (p < 0.001). CONCLUSIONS: The present study shows that plasma BNP levels reflect left ventricular EDWS more than any other parameter previously reported, not only in patients with SHF, but also in patients with DHF. The relationship of left ventricular EDWS to plasma BNP may provide a better fundamental understanding of the interindividual heterogeneity in BNP levels and their clinical utility in the diagnosis and management of HF.     

Hypoalbuminemia in elderly patients with acute diastolic heart failure

OBJECTIVES: This study evaluated the relative contribution of serum colloid osmotic pressure (COP) lowering and pulmonary artery wedge pressure (PAWP) elevation in the pathogenesis of pulmonary edema in patients with systolic or isolated diastolic heart failure (DHF). BACKGROUND: The role of hypoalbuminemia and the resulting low COP have been shown in some patients with acute systolic heart failure (SHF).Colloid osmotic pressure and PAWP were determined in 100 patients with acute heart failure (HF) (56 with DHF and 44 with SHF; mean age, 78 +/- 12 years), in 35 patients with acute dyspnea from pulmonary origin, and in 15 normal controls. Pulmonary artery wedge pressure was estimated using transthoracic Doppler echocardiography. RESULTS: Colloid osmotic pressure was significantly lower in the DHF group (20.5 +/- 5 mm Hg) than in the SHF group (24.2 +/- 3.7 mm Hg, p < 0.001), pulmonary disease group (25.1 +/- 4.2 mm Hg, p < 0.001), or normal control group (24.7 +/- 3 mm Hg). Low COP resulted from hypoalbuminemia due to age, malnutrition, and sepsis. Pulmonary artery wedge pressure was significantly higher in patients with SHF (26 +/- 6.3 mm Hg) than in the patients with DHF (20.3 +/- 7 mm Hg, p < 0.001) and was significantly higher in the patients with DHF than in the patients with pulmonary disease (13 +/- 4.2 mm Hg, p < 0.001). The COP-PAWP gradient was similar in patients with SHF (-1.6 +/- 7.1 mm Hg) and patients with DHF (0.7 +/- 6 mm Hg). CONCLUSIONS: Frequent hypoalbuminemia resulting in low COP facilitates the onset of pulmonary edema in patients with DHF who usually have lower PAWP than patients with SHF.     

Differential activation of matrix metalloproteinases in heart failure with and without ventricular dilatation

OBJECTIVE: Remodeling of extracellular matrix (ECM) is considered to contribute to progression of left ventricular (LV) remodeling and matrix metalloproteinases (MMPs) play crucial roles in regulation of ECM. Activation of MMPs is observed in systolic heart failure (SHF) and is suggested to be responsible for LV dilatation in SHF. Diastolic heart failure (DHF) that is not associated with LV dilatation is also accompanied with collagen accumulation; however, differences in ECM regulatory system, especially activation of MMPs, between SHF and DHF remain to be clarified. This study was conducted to clarify whether MMPs are activated even in DHF, and if so, to characterize the difference in activation of MMPs between SHF and DHF for identification of a target for the prevention of LV remodeling in SHF. METHODS: To exclude effects of differences in underling cardiovascular diseases and genetic background on the comparison between DHF and SHF, we used Dahl salt-sensitive rats fed on high salt diet starting at 7 weeks of age as DHF model and at 8 weeks as SHF model, both of which our laboratory recently developed. RESULTS: LV fibrosis progressed in the DHF and SHF model rats. MMP-2 was activated to the same degree in both rats. Activation of MMP-9 was enhanced in the DHF model rats, but the activity was more enhanced in the SHF rats. Film in situ zymography showed that enhanced gelatinolytic activity appeared only in the mid layer of the LV wall in the DHF rats and throughout the wall in the SHF rats. The distribution of gelatinolytic activity was consistent with that of expression of MMP-9 as assessed in immunohistochemical study. CONCLUSIONS: MMP-9 rather than MMP-2 may be involved in LV dilatation in SHF and be a specific target for the prevention of LV remodeling.     

Long-term effects of benidipine hydrochloride on severe left ventricular hypertrophy and collagen metabolism in patients with essential hypertension

OBJECTIVES: The long-term effects of benidipine on left ventricular hypertrophy (LVH) and collagen metabolism were examined in patients with essential hypertension. METHODS: Forty patients with untreated essential hypertension were given benidipine at a dose of 6 mg a day. Routine echocardiographic parameters, serum concentrations of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were analyzed before and 12 months after treatment with benidipine. Patients were classified according to left ventricular mass index (LVMI) into three groups: severe LVH (LVMI > or = 159), mild LVH (159 > LVMI > or = 125) and no LVH (LVMI < 125). RESULTS: Serum levels of free TIMP-1 to MMP-1 ratio were significantly higher in patients with severe LVH than in the other two groups before treatment. There was a significant positive correlation between the free TIMP-1 to MMP-1 ratio and LVMI in all study subjects (r = 0.51, p < 0.01). Twelve months after treatment, percentage changes of the LVMI and free TIMP-1 to MMP-1 ratio were significantly larger in the patients with severe LVH (-27% and -54%) than with mild LVH (-12% and -23%) or no LVH (-4% and -11%), respectively. Changes in the systolic blood pressure but not changes in the free TIMP-1 to MMP-1 ratio correlated with changes in the LVMI in patients with mild LVH (r = 0.78, p < 0.01). Changes in the free TIMP-1 to MMP-1 ratio but not changes in the systolic blood pressure correlated with changes in the LVMI in patients with severe LVH (r = 0.69, p < 0.01). CONCLUSIONS: Long-term administration of benidipine reduced left ventricular mass and normalized systemic collagen type I degradation abnormalities in essential hypertensive patients with severe but not mild LVH.     

Collagen type-I degradation is related to arterial stiffness in hypertensive and normotensive subjects

Although arterial stiffness is an independent cardiovascular risk factor associated with both aging and hypertension, relatively little is known regarding the structural changes in the vessel wall that occur with vessel stiffening. We determined if collagen type-I metabolism is related to arterial stiffening in both hypertensive and normotensive subjects. Arterial stiffness was assessed by aortic pulse wave velocity (PWV) and augmentation index (AIx) in 46 subjects (48.7 +/- 2 years, 32 hypertensives) and related to circulating markers of collagen type-I turnover. Collagen synthesis was assessed by the measurement of carboxy-terminal peptide of procollagen type-I (PIP) and collagen degradation by the measurement of carboxy-terminal telopeptide of collagen type-I (ICTP), by quantitative immunoassay. Matrix metalloproteinase-1 (MMP-1) and the tissue inhibitor of metalloproteinase-1 (TIMP-1) were also quantified by immunoassay. The ratio of collagen type-I synthesis to degradation was negatively correlated with both PWV (P<0.05) and AIx (P<0.05), whereas plasma MMP-1 levels displayed a positive correlation with both PWV (P<0.01) and AIx (P<0.01), after adjustment for age and mean arterial pressure. The relationship between collagen type-I turnover and arterial stiffness was similar in both the normotensive and hypertensive subjects. Although circulating markers of collagen synthesis were increased in the hypertensive subjects, this was not related to arterial stiffness. Collagen type-I degradation is increased in relation to collagen type-I synthesis in subjects with stiffer arteries. Matrix metalloproteinase-1, the enzyme responsible for collagen type-I degradation, is positively related to both large elastic and muscular artery stiffness in normotensive and hypertensive subjects.     

Matrix metalloproteinase-9 and tissue inhibitor metalloproteinase-1 levels in essential hypertension. Relationship to left ventricular mass and anti-hypertensive therapy

To test the hypothesis that the activity of enzymes degrading the extracellular matrix in hypertensive patients are abnormal, and that the treatment of hypertension will normalise these abnormalities, we measured the serum levels of metalloproteinase MMP-9, and its inhibitor, tissue metalloproteinase inhibitor (TIMP-1). Thirty-two patients with untreated hypertension (BP 168/96) had significantly lower levels of both MMP-9 and TIMP-1 when compared to 24 matched normotensive controls (BP 123/80) (P<0.001). There was no significant correlation between MMP-9 and TIMP-1 levels (P>0.2). In the patients, there were no significant correlations observed between left ventricular mass, Doppler V(E)/V(A) ratio (an index of diastolic function), blood pressure, left ventricular mass index and either MMP-9 or TIMP-1 levels (all P=NS). Levels of MMP-9 and TIMP-1 were not significantly altered after 2 months of antihypertensive treatment of 29 patients despite mean blood pressure falling from 170/96 to 143/85 mmHg (P<0.001). Correspondingly, there were also no significant alterations in indices of diastolic function and left ventricular mass. Our study suggests that the proteolytic activities of MMP-9 and TIMP-l are depressed in hypertensive patients and were not significantly affected by short-term antihypertensive treatment. The relationship between collagen metabolism in hypertensive subjects, especially in those with cardiac hypertrophy, and the effects of treatment needs to be further explored in larger trials over a longer period of time.     

Serum levels of MMP-9 and TIMP-1 in primary hypertension and effect of antihypertensive treatment

BackgroundMatrix metalloproteinases, a family of proteolytic enzymes are thought to be involved in extracellular matrix accumulation during development of hypertensive target organ disease. The present study was designed to compare hypertensive patients with normotensive individuals with respect to serum levels of matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 and to search for the effect of antihypertensive treatment on the serum enzyme levels.MethodsThirty-three patients with stage 1 primary hypertension and sixteen age- and sexmatched control subjects were enrolled into the study. Serum MMP-9 and TIMP-1 levels were assessed in the hypertensive group before and after a 3-month-antihypertensive treatment (candesartan 8 mg/day to 17 patients and lisinopril 10 mg/day to 16 patients).ResultsPre-treatment serum MMP-9 levels were higher in the hypertensive group (p = 0.309) while serum TIMP-1 levels were lower (p = 0.296). Serum MMP-9 levels were decreased (p < 0.001) and TIMP-1 levels were increased (p = 0.022) after the antihypertensive treatment.ConclusionsIn hypertensive patients, increased MMP-9 activity could result in increased degradation of elastin relative to collagen and non-elasticity, while decreased TIMP-1 activity could lead to accumulation of poorly cross-linked, immature and unstable fibril degradation products, which result in misdirected deposition of collagen. Our study is important for revealing the role of the MMP enzyme system in the pathogenesis of hypertensive target organ disease.     

基质金属蛋白酶在心肌肥厚大鼠中的作用及强力霉素的干预效果

目的:观察心肌肥厚大鼠模型中基质金属蛋白酶(MMP)-2,MMP-9及其抑制剂(TIMP-1)的表达及强力霉素干预后对其影响。方法:24只大鼠随机分为对照组(A组,只给予0.9%氯化钠溶液腹腔注射);造模组(B组)和药物干预组(C组)均用去甲肾上腺素1.06mg/kg腹腔注射,bid,注射15d,建立大鼠心肌肥厚模型,C组造模同时给予强力霉素10mg/kg腹腔注射,qd,给药15d。全部动物于给药后16d处死测定全心质量指数、左室质量指数、心肌胶原含量、心肌组织MMP-2,MMP-9,TIMP-1、心肌胶原容积分数(CVF)。结果:与A组比较,B组全心质量指数、左室质量指数、MMP-2、MMP-9阳性表达率、心肌胶原含量及CVF均明显增加(P<0.05),TIMP-1阳性表达率明显降低(P<0.05)。与B组比较,C组全心质量指数、左室质量指数、MMP-2、MMP-9阳性表达率、心肌胶原含量及CVF均明显降低(P<0.05),TIMP-1阳性表达率增加(P<0.05)。结论:去甲肾上腺素诱导的心肌肥厚大鼠MMPs/TIMPs系统平衡破坏,使基质胶原降解与合成平衡破坏,从而导致心室重构。强力霉素可通过抑制MMP来逆转心室重构。     

Collagen metabolism in extracellular matrix may be involved in arterial stiffness in older hypertensive patients with left ventricular hypertrophy.

Collagen metabolism in the extracellular matrix (ECM) is related to the pathogenesis of cardiovascular stiffness and remodeling in hypertension. We evaluated the association between collagen metabolism markers and the newly developed parameter, brachial-ankle pulse wave velocity (baPWV), in older hypertensive patients with left ventricular hypertrophy (LVH). We performed echocardiography and baPWV measurement using a new device, form PWV/ABI (Colin Medical Technology, Komaki, Japan), and measured plasma levels of markers of collagen metabolism such as procollagen type I C-terminal propeptide (PICP: a marker of collagen synthesis), collagen type I pyridinoline cross-linked C-terminal telopeptide (ICTP: a marker of collagen type I degradation), matrix metalloproteinase-1 (MMP-1: a marker of collagen degradation) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in 46 hypertensive patients with LVH. BaPWV was correlated with the plasma level of PICP (r=0.33, p=0.03) and ICTP (r=0.29, p=0.05) and the total TIMP-1/MMP-1 ratio (an index of collagen turnover; r=0.30, p=0.04). BaPWV was negatively correlated with the E/A ratio of left ventricular inflow (r=-0.36, p<0.05), while baPWV was not correlated with left ventricular mass index (LVMI; r=-0.175, p=0.25) or deceleration time of the mitral E wave (DCT; r=0.15, p=0.31). The measures of hypertensive heart disease, such as the E/A ratio, DCT or LVMI were not correlated with any collagen markers in this study. In multiple regression analysis adjusted for confounding factors such as age, sex, pulse pressure, mean blood pressure, pulse rate, LVMI, E/A ratio and DCT, the positive correlation between baPWV and total TIMP-1/MMP-1 ratio remained significant (p<0.05). In conclusion, arterial stiffness in high-risk older hypertensive patients may involve ECM collagen metabolism.     

Diastolic and systolic asynchrony in patients with diastolic heart failure: a common but ignored condition.

OBJECTIVES: The present study aimed to examine whether diastolic and systolic asynchrony exist in diastolic heart failure (DHF) and their prevalence and relationship to systolic heart failure (SHF) patients. BACKGROUND: Few data exist on mechanical asynchrony in DHF. METHODS: Tissue Doppler echocardiography was performed in 373 heart failure patients (281 with SHF and 92 with DHF) and 100 normal subjects. Diastolic and systolic asynchrony was determined by measuring the standard deviation of time to peak myocardial systolic (Ts-SD) and peak early diastolic (Te-SD) velocity using a 6-basal, 6-mid-segmental model, respectively. RESULTS: Both heart failure groups had prolonged Te-SD (DHF vs. SHF vs. controls subjects: 32.2 +/- 18.0 ms vs. 38.0 +/- 25.2 ms vs. 19.5 +/- 7.1 ms) and Ts-SD (31.8 +/- 17.0 ms vs. 36.7 +/- 15.2 ms vs. 17.6 +/- 7.9 ms) compared with the control group (all p < 0.001 vs. control subjects). Based on normal values, the DHF group had comparable diastolic (35.9% vs. 43.1%; chi-square = 1.48, p = NS), but less systolic asynchrony than the SHF group (39.1% vs. 56.9%; chi-square = 8.82, p = 0.003). Normal synchrony, isolated systolic, isolated diastolic, and combined asynchrony were observed in 39.1%, 25.0%, 21.7%, and 14.1% of DHF patients, respectively, and these were 25.6%, 31.3%, 17.4%, and 25.6%, correspondingly, in SHF (chi-square = 10.01, p = 0.019). The correlation between systolic and diastolic asynchrony, and between the myocardial velocities and corresponding mechanical asynchrony appeared weak. A wide QRS duration (>120 ms) was rare in DHF (10.9% vs. 37.7% in SHF) (chi-square = 16.69, p < 0.001). CONCLUSIONS: Diastolic and/or systolic asynchrony was common in 61% of DHF patients despite narrow QRS complex. The presence of asynchrony was not related to myocardial systolic or diastolic function. Systolic and diastolic asynchrony were not tightly coupled, implying distinct mechanisms.     

Downregulation of vascular matrix metalloproteinase inducer and activator proteins in hypertensive patients

BACKGROUND: Peripheral vasculature undergoes extensive vascular remodeling in the hypertensive state. Regulation of extracellular matrix turnover by the matrix metalloproteinase (MMP) system is an important step in the vascular remodeling process. However, the expression pattern of the vascular MMP system in human hypertension remained unknown. METHODS AND RESULTS: Internal mammary artery specimens were obtained from normotensive (n = 13) and hypertensive (n = 19) patients undergoing coronary artery bypass grafting surgery. Zymographic analysis indicated a threefold decrease in total gelatinolytic activity of MMP-2 and MMP-9 in hypertension. MMP-1 activity was also decreased by fourfold without a significant change in protein levels. Tissue levels of extracellular matrix inducer protein (EMMPRIN), MMP activator protein (MT1-MMP), MMP-1, MMP-2, and MMP-9, as well as tissue inhibitors of MMPs (TIMP-1 and TIMP-2) were assessed by immunoblotting and yielded a significant decrease in MMP-9, EMMPRIN, and MT1-MMP levels in hypertension. In addition, measurement of plasma markers of collagen synthesis (procollagen type I amino-terminal propeptide [PINP]) and collagen degradation (carboxy-terminal telopeptide of collagen type I [ICTP]) indicated no difference in PINP levels but suppressed degradation of collagen in hypertension. Evaluation of profibrotic growth factors demonstrated higher levels of fibroblast growth factor (FGF)-2 in tissue preparations from hypertensive patients but no difference in transforming growth factor-beta1 levels. CONCLUSIONS: These findings demonstrate that not only MMP-1 and MMP-9, but MMP inducer and activator proteins are also downregulated in the hypertensive state. Augmented FGF-2 levels may contribute to parallel decreases in MMP activity and MMP induction system resulting in enhanced collagen deposition in hypertension.     

Impact of the metalloproteinase-9/tissue inhibitor of metalloproteinase-1 system on large arterial stiffness in patients with essential hypertension.

The extracellular matrix is vital for maintaining tissue integrity, and the matrix metalloproteinases/tissue inhibitors of metalloproteinases (MMPs/TIMPs) system is involved in the regulation of extracellular matrix metabolism. Extracellular matrix turnover plays an important role in the change of large arterial mechanical properties in hypertension. However, the association of the metalloproteinase-9/tissue inhibitor of metalloproteinase-1 (MMP-9/TIMP-1) system and arterial stiffness is not straightforward and existing data are rather limited. Our objective is to explore the impact of the MMP-9/TIMP-1 system on large arterial stiffness in patients with essential hypertension. An automatic pulse wave velocity (PWV) measuring system was used to examine carotid-femoral PWV (CFPWV) and carotid-radial PWV (CRPWV) as the parameters reflecting central elastic large arterial and peripheral muscular medium-sized arterial elasticity, respectively; and serum MMP-9 and TIMP-1 levels, along with a number of other established biomarkers, were measured by enzyme-linked immunosorbent assay (ELISA) in 202 essential hypertensive patients and 54 age and gender-matched control subjects. Compared with the control subjects, hypertensive patients exhibited higher levels of MMP-9 (p=0.001) and TIMP-1 (p=0.002). Spearman's correlation analysis showed that serum levels of MMP-9 (p=0.014) and TIMP-1 (p=0.005) were significantly and positively correlated with CFPWV in hypertensive patients. A stepwise multiple regressive analysis demonstrated that age, systolic blood pressure, heart rate and TIMP-1 were independent predictors of CFPWV in patients with essential hypertension (adjusted r2=0.458). In conclusion, our results imply that the MMP-9/TIMP-1 system may play an important role in the determination of arterial function, and these findings may have implications for the involvement of MMP-9/TIMP-1 system in the pathophysiology of cardiovascular disease.     

Systolic and diastolic dyssynchrony in patients with diastolic heart failure and the effect of medical therapy.

OBJECTIVES: The purpose of this study was to determine the prevalence of systolic and diastolic dyssynchrony in diastolic heart failure (DHF) patients and identify the effects of medical therapy. BACKGROUND: The prevalence of systolic and diastolic dyssynchrony in DHF patients is unknown with no data on the effects of medical therapy on dyssynchrony. METHODS: Patients presenting with DHF (n = 60; 61 +/- 9 years old, 35 women) underwent echocardiographic imaging simultaneous with invasive measurements. An age-matched control group of 35 subjects and 60 patients with systolic heart failure (SHF) were included for comparison. Systolic and diastolic dyssynchrony were assessed by tissue Doppler and defined using mean and SD values in the control group. RESULTS: Systolic dyssynchrony was present in 20 patients (33%) with DHF and 24 patients (40%) with SHF and was associated in both groups with significantly worse left ventricular (LV) systolic and diastolic properties (p < 0.05 vs. control group and patients without systolic dyssynchrony). Diastolic dyssynchrony was present in 35 patients (58%) with DHF and 36 patients (60%) with SHF and had significant inverse correlations with mean wedge pressure and time constant of LV relaxation. In DHF patients, medical therapy resulted in significant shortening of diastolic time delay (39 +/- 23 ms to 28 +/- 20 ms; p = 0.02) but no significant change in systolic interval (p = 0.15). Shortening of diastolic time delay correlated well with tau shortening after therapy (r = 0.85; p < 0.001). CONCLUSIONS: Systolic dyssynchrony occurs in 33% of DHF patients, and diastolic dyssynchrony occurs in 58%. Medical therapy results in significant shortening of the diastolic intraventricular time delay which is closely related to improvement in LV relaxation.     

Comprehensive Evaluation of the Effects of Enalapril on Matrix Metalloproteinases Levels in Hypertension

Purpose

Angiotensin-converting enzyme inhibitors (ACEi) may downregulate matrix metalloproteinases (MMPs). We examined whether enalapril affects MMP-2, MMP-8, and MMP-9 levels and activity, and their endogenous inhibitors (tissue inhibitors of MMPs, TIMP-1 and TIMP-2) levels in hypertensive patients. Moreover, we assessed the effects of enalaprilat on MMP-9 and TIMP-1 secretion by human endothelial cells (HUVECs).

Methods

Thirty-eight hypertensive patients received enalapril for 8 weeks and were compared with thirty-eight normotensive controls. Blood samples were collected at baseline and after treatment. Plasma ACE activity was determined by a fluorimetric assay. Plasma MMP-2, MMP-8, MMP-9, TIMP-1, and TIMP-2 were measured by ELISA and gelatin zymography. A fluorogenic peptide cleavage assay was used to measure MMP activity. HUVECs cells were stimulated by phorbol-12-myristate-13-acetate (PMA) and the effects of enalaprilat (10^?10 to 10^?6?M) on MMP-9 and TIMP-1 levels were determined.

Results

Enalapril decreased blood pressure and ACE activity in hypertensive patients (P?<?0.05), but had no effects on plasma MMP-2, MMP-8, MMP-9, TIMP-1, and TIMP-2 levels, or MMP activity. Enalaprilat had no effects on PMA-induced increases in MMP-9 and TIMP-1 secretion by HUVECs or on MMP activity.

Conclusions

We show consistent evidence, both in vivo and in vitro, that enalapril does not affect MMPs and TIMPs levels in hypertensive patients.

     

老年高血压患者颈动脉内膜中层厚度与基质金属蛋白酶9及其组织型抑制剂1水平的关系

目的 探讨老年高血压患者颈动脉内膜中层厚度(IMT)与血清基质金属蛋白酶9(MMP-9)及基质金属蛋白酶组织型抑制剂1(TIMP-1)的相关性.方法 选择老年高血压患者135例作为高血压组,并按24 h动态脉压分为4个亚组,脉压≤40 mm Hg(1 mm Hg=0.133 kPa)为A组14例、41～60 mm Hg...     

Increased levels and activity of matrix metalloproteinase-9 in obstructive sleep apnea syndrome

Matrix metalloproteinases (MMPs) are involved in the pathogenesis of cardiovascular diseases. We examined serum levels of MMP-9 and its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), activity of MMP-9, and the effect of nasal continuous positive airway pressure (nCPAP) in patients with obstructive sleep apnea syndrome (OSAS). After polysomnography, venous blood was collected at 5:00 A.M. from 44 patients with OSAS and 18 control subjects who were obese, and serum levels of MMP-9, TIMP-1, and enzymatic activity of MMP-9 were measured. In addition, the effects of 1 month of treatment with nCPAP were studied in patients with moderate to severe OSAS. Although serum levels of MMP-9 (p < 0.03) and MMP-9 activity (p < 0.01) were higher in patients with OSAS than in control subjects who were obese, TIMP-1 levels did not differ significantly. In patients with OSAS, the severity of OSAS was the primary factor influencing levels (p < 0.01) and activity (p < 0.01) of MMP-9. nCPAP significantly decreased serum levels (p < 0.01) and activity (p < 0.001) of MMP-9 but did not affect TIMP-1 levels. Therefore, OSAS may increase risks of cardiovascular morbidity, and nCPAP might be useful for decreasing these risks.