Association of Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 With Endothelial Dysfunction, Cardiovascular Disease Risk Factors and thrombotic events in Children With End-stage Renal Disease

INTRODUCTION

Cardiovascular disease (CVD) is the main cause of death in children with end-stage renal disease (ESRD). Matrix metalloproteinases (MMP-2 and MMP-9) are members of endopeptidases which contribute to CVD. The aim of this study was to evaluate the association of MMP-2 and MMP-9 with markers of endothelial dysfunction, soluble E-selectin and brachial flow-mediated dilatation; several biochemical risk factors of CVD; and thrombotic incidents in children with ESRD.

MATERIALS AND METHODS

Thirty-one children with ESRD and 18 healthy age- and sex-adjusted controls underwent measurement of serum levels of MMP-2, MMP-9, soluble E-selectin, phosphorus, calcium, parathyroid hormone, lipid profile, thrombotic factors, and albumin. Flow-mediated dilatation was measured in both groups by Doppler ultrasonography. Thrombotic events were assessed in patients with ESRD.

RESULTS

Matrix metalloproteinase-2 positively correlated with systolic and diastolic blood pressure, soluble E-selectin, creatinine, cholesterol, triglyceride, low-density lipoprotein cholesterol, phosphorus, and parathyroid hormone and negatively correlated with body mass index, hemoglobin, high-density lipoprotein cholesterol, and flow-mediated dilatation, while MMP-9 correlated with soluble E-selectin, phosphorus, parathyroid hormone, and albumin and negatively correlated with body mass index and hemoglobin. Six patients (19.3%) had thrombotic incidents. There was no significant difference between the levels of MMP-2 and MMP-9 in the children with and without thrombotic events.

CONCLUSIONS

This study determined the associations of MMP-2 and MMP-9 with markers of endothelial dysfunction and several traditional and uremia related CVD risk factors in children with ESRD. No associations were found between these two MMPs and thrombotic events.

Effect of vitamin C on endothelial function of children with chronic renal failure: An experimental study

Background:

It is well established that improvement of endothelial dysfunction (ED) could prevent or delay the occurrence of cardiovascular disease (CVD) and its related morbidity and mortality in patients with chronic kidney disease (CKD). In this study we investigated whether administration of vitamin C could be effective by improving brachial artery flow-mediated dilation (FMD) and intima media thickness (IMT), two surrogate markers of ED, in children with CKD or chronic renal failure (CRF).

Materials and Methods:

In this analytic-experimental study children aged 3-18 years with a diagnosis of CRF and a group of healthy children were enrolled. Vitamin C (250 mg/day) administrated for the two studied groups for 1 month. Endothelial function was evaluated by FMD and IMT measurement using vascular Doppler ultrasonography, before and after trial.

Results:

In this study 18 patients with CRF and 19 normal children as the control group were studied. At baseline mean of IMT and FMD was not different in the two studied groups (P > 0.05). After vitamin C administration IMT decreased significantly in the two studied groups (P < 0.05). FMD increased in the two studied groups but the difference was significant in the control group (P < 0.05).

Conclusion:

The findings of this interventional trial have demonstrated that vitamin C could have protective effect on ED of patients with CRF possibly in those with severe form of the disease but for obtaining more conclusive results larger sample size is needed.

Does Vitamin C improve endothelial function in patients with Kawasaki disease?

BACKGROUND

Improvement of endothelial dysfunction could prevent or delay the occurrence of the atherosclerosis process in patients with Kawasaki disease (KD). It is suggested that Vitamin C could improve endothelial dysfunction. In this study, we investigated whether administration of Vitamin C as a water-soluble antioxidant could be effective in this regard among patients with KD.

MATERIALS AND METHODS

In this case control analytic-experimental study, children aged 3-18 years with KD, and a group of healthy children evaluated. Vitamin C (250 mg/daily) administrated for the two studied groups for 1 month. Endothelial function evaluated by flow-mediated dilatation (FMD) and intima-media thickness (IMT) measurement using vascular Doppler ultrasonography, before and after trial.

RESULTS

In this study, 16 patients with KD and 19 normal children were studied. At baseline mean of IMT and FMD was not different in the two studied groups (P > 0.05). After Vitamin C administration IMT decreased significantly in two studied groups (from 27.06 ± 6.27 to 21.56 ± 3.77 in KD group and from 27.66 ± 5.66 to 23.33 ± 3.66 in control group [P < 0.05]). FMD increased in two studied groups, but the difference was significant in the control group (from 6.84 ± 2.51 to 7.03 ± 2.87 in KD group and from 6.53 ± 2.36 to 7.82 ± 2.14 in the control group).

CONCLUSION

Vitamin C might improve the endothelial function of patients with KD.

The effect of vitamin C on endothelial function of children with type 1 diabetes: an experimental study

BACKGROUND

Considering the importance of improvement of endothelial function in patients with type 1 diabetes mellitus (DM) and to prevent its related micro- and macro-vascular complications; in this study, the effect of vitamin C administration on improving endothelial function of children with type 1 diabetes was investigated.

METHODS

In this analytic-experimental study, children with type 1 DM aged 6-18 years and a group of healthy children enrolled. Vitamin C (250 mg/daily) administrated for the two studied groups for 1-month. Endothelial function evaluated by flow-mediated dilatation (FMD) and intima-media thickness (IMT) measurement using vascular Doppler ultrasonography, before and after trial.

RESULTS

In this study, 18 patients with type 1 diabetes (DM) and 19 normal children as the control group were studied. After vitamin C administration IMT reduced in all studied groups (P < 0.05). FMD increased in all studied groups, but it was significant only in the control group (P = 0.02 in the control group and P = 0.07 in patients with DM). Mean differences of IMT 2 - IMT 1, FMD 2 - FMD 1 and left ventricular (LV) mass 2 - LV mass 1 and blood pressure (BP) were not significantly different in two studied groups (P > 0.05). Mean differences of IMT 2 - IMT 1, FMD 2 - FMD 1, LV mass 2 - LV mass 1 and BP were not significantly different in patients with HbA1c ≤ 7 g/dl and those with HbA1c >7 g/dl and control group (P > 0.05).

CONCLUSIONS

The findings of the current study indicated that vitamin C may have a protective effect on endothelial dysfunction, but regarding its effectiveness among the high-risk population such as diabetic patients with and without appropriate glycemic control the study was not sufficiently powered due to its small sample size.