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Gian Paolo Fadini

Publications and source records attributed to Gian Paolo Fadini.

15 recordsLinked to original sources
PubMed2006

Circulating CD34+ cells, metabolic syndrome, and cardiovascular risk.

AIMS: Circulating progenitor cells are believed to participate in cardiovascular (CV) homeostasis and their exhaustion has been linked to CV damage. As general agreement on their characterization is lacking, this work was carried out to assess the relationships between different antigenic profiles of progenitor cells and CV risk, with special regard to metabolic syndrome (MetSyn). METHODS AND RESULTS: CD34, CD133, and KDR were used to quantify circulating progenitors in 214 subjects at different levels of CV risk. In a cross-analysis of six different cell subtypes (CD34(+), CD133(+), CD34(+)CD133(+), CD34(+)KDR(+), CD133(+)KDR(+), and CD34(+)CD133(+)KDR(+)), CD34(+) progenitors showed the best correlation with CV parameters and risk estimates. Components of the MetSyn were all characterized by reduction of CD34(+) cells and acted synergistically in decreasing CD34(+) cell count. Moreover, CD34(+) cell count demonstrated a high performance in detecting high CV risk. CONCLUSION: These data demonstrate that CD34 identifies progenitor cells linked to CV risk, showing a close negative correlation between CD34(+) cells and CV risk, as well as a synergic detrimental effect of clustered metabolic components. Progenitor cell count may be used as a surrogate marker of CV risk, whereas extensive antigenic characterization may not be useful for this purpose.

Antigens, CD34↗
PubMed2006

Peripheral blood CD34+KDR+ endothelial progenitor cells are determinants of subclinical atherosclerosis in a middle-aged general population.

BACKGROUND AND PURPOSE: Disruption of the endothelial layer is the first step in the atherogenic process. Experimental studies have shown that endothelial progenitor cells (EPCs) are involved in endothelial homeostasis and repair. Conversely, EPC depletion has been demonstrated in the setting of established atherosclerotic diseases. With this background, we evaluated whether variations in the number of EPCs are associated with subclinical atherosclerosis in healthy subjects. METHODS: Carotid intima-media thickness (IMT), high-sensitive C-reactive protein (hsCRP), levels of circulating EPCs, and cardiovascular risk were compared in 137 healthy subjects. Six subpopulations of progenitor cells were determined by flow cytometry on the basis of the surface expression of CD34, CD133, and KDR antigens: CD34(+), CD133(+), CD34(+)CD133(+), CD34(+)KDR(+), CD133(+)KDR(+), and CD34(+)CD133(+)KDR(+). RESULTS: Among different antigenic profiles of EPCs, only CD34(+)KDR(+) cells were significantly reduced in subjects with increased IMT. Specifically, CD34(+)KDR(+) cells were inversely correlated with IMT, even after adjustment for hsCRP and 10-year Framingham risk and independently of other cardiovascular parameters. CONCLUSIONS: Depletion of CD34(+)KDR(+) EPCs is an independent predictor of early subclinical atherosclerosis in healthy subjects and may provide additional information beyond classic risk factors and inflammatory markers.

Adult↗
PubMed2006

Number and function of endothelial progenitor cells as a marker of severity for diabetic vasculopathy.

OBJECTIVE: Peripheral arterial disease (PAD) is a threatening complication of diabetes. As endothelial progenitor cells (EPCs) are involved in neovasculogenesis and maintenance of vascular homeostasis, their impairment may have a role in the pathogenesis of diabetic vasculopathy. This study aimed to establish whether number and function of EPCs correlate with PAD severity in type 2 diabetic patients. METHODS AND RESULTS: EPCs were defined by the expression of CD34, CD133 and KDR, and quantified by flow cytometry in 127 diabetic patients with and without PAD. PAD severity has been assessed as carotid atherosclerosis and clinical stage of leg atherosclerosis obliterans. Diabetic patients with PAD displayed a significant 53% reduction in circulating EPCs versus non-PAD patients, and EPC levels were negatively correlated with the degree of carotid stenosis and the stage of leg claudication. Moreover, the clonogenic and adhesion capacity of cultured EPCs were significantly lower in diabetic patients with PAD versus patients without. CONCLUSIONS: This study demonstrates that EPC decrease is related to PAD severity and that EPC function is altered in diabetic subjects with PAD, strengthening the pathogenetic role of EPC dysregulation in diabetic vasculopathy. EPC count may be considered a novel biological marker of peripheral atherosclerosis in diabetes.

Aged↗
PubMed2006

Circulating progenitor cells are reduced in patients with severe lung disease.

Patients with chronic severe lung disease are prone to develop pulmonary vascular remodeling, possibly through pulmonary endothelial dysfunction. Circulating endothelial progenitor cells (EPCs) are involved in maintenance of endothelial homeostasis. The aim of this study was to assess whether obstructive and restrictive lung diseases are associated with modification of EPC number in peripheral blood. The study was cross-sectional and involved patients with obstructive (n = 15) and restrictive (n = 15) lung disease on oxygen therapy and 15 control subjects. Circulating EPCs were defined by the surface expression of CD34, CD133, and kinase-insert domain receptor. Results from spirometric tests, blood gas analyses, and blood cell counts have been related to EPC numbers. Patients with chronic hypoxia and severe lung disease showed lower levels of all progenitors than do control subjects. A consensual further reduction of EPC was found in restrictive patients in comparison with obstructive patients. Among restrictive patients, EPC reduction was related to reduced lung volumes and impaired alveolo-arterial diffusion, whereas progenitor cell levels were directly related to erythrocyte number. Considering obstructive patients, significant correlations were found between progenitor cell levels and bronchial obstruction and between progenitor cell levels and arterial oxygen tension. These findings demonstrate a reduction of EPCs in patients with chronic lung disease and long-lasting hypoxia. This alteration was more evident in restrictive patients and correlated to disease severity. Depletion of circulating EPCs may be involved in altered endothelial homeostasis of pulmonary circulation in these disorders.

Aged↗
PubMed2006

Endothelial dysfunction in type 2 diabetes mellitus.

AIMS: Vascular endothelial cells play a major role in maintaining cardiovascular homeostasis in health. Diabetes mellitus (DM) substantially impairs the vasodilating properties of the endothelium and leads to endothelial dysfunction, which can thus be considered the first step in the progression of cardiovascular disease. The aim of the present study is to illustrate possible mechanisms responsible for endothelial dysfunction in DM. DATA SYNTHESIS: We have shown that NADPH oxidase gene expression is increased in circulating lymphomonocytes from patients with DM, and that this increased gene expression is dependent upon metabolic control. Hyperglycemia can mediate its adverse effects through the activation of protein kinase C. We have shown an increase in membrane-associated PKC beta 2 activity in monocytes from patients with DM. This activity was reduced by 40% in the euglycemic condition. Finally, we show a reduction of the circulating endothelial progenitor cells, a subset of bone marrow-derived endothelial-oriented stem cells, which can give rise to mature endothelial cells. CONCLUSION: Endothelial dysfunction, the initial step of the atherosclerotic process, is reversible. Thus, major efforts should be made to control not only hyperglycemia but also the other risk factors for cardiovascular disease, in order to prevent the onset of all these processes that eventually leads the diabetic patient to premature death.

Diabetes Complications↗
PubMed2005

Circulating endothelial progenitor cells are reduced in peripheral vascular complications of type 2 diabetes mellitus.

OBJECTIVES: We sought to establish whether a reduction in endothelial progenitor cells (EPCs) has a putative role in peripheral vascular disease (PVD) of type 2 diabetic patients. BACKGROUND: Peripheral vascular disease is a common and severe complication of diabetes mellitus. Impaired collateralization of diabetic vasculopathy has been extensively shown, but causes leading to its pathogenesis are not fully understood. Recently, EPCs have been found to contribute to vascular repair and angiogenesis. Diabetes has been associated with low levels of circulating EPCs, but no data are available in the literature on the relationship between EPCs and PVD in diabetes. METHODS: Flow cytometric analysis was used to quantify circulating progenitor cells (CPCs, CD34+) and EPCs (CD34+KDR+) in 51 patients and 17 control subjects. RESULTS: The CPCs and EPCs from diabetic patients were reduced by 33% and 40%, respectively, compared with healthy subjects (p < 0.001). An inverse correlation was found between the number of EPCs and the values of fasting glucose (r = -0.49, p = 0.006). Peripheral vascular disease was associated with a 47% reduction in EPCs (p < 0.0001) and EPC levels directly correlated with the ankle-brachial index (r = 0.70, p = 0.01). The subgroup of diabetic patients with PVD also had reduced CPCs by 32% (p = 0.037), whereas patients with ischemic foot lesions had the lowest levels of both EPCs and CPCs (p = 0.02). CONCLUSIONS: Our data demonstrate decreased EPC levels in diabetic patients and, for the first time, show that PVD is associated with an extensively low number of EPCs. Depletion of circulating EPCs in diabetic patients may be involved in the pathogenesis of peripheral vascular complications.

Aged↗
PubMed2005

Arterio-venous gradient of endothelial progenitor cells across renal artery stenosis.

A role for circulating progenitor cells have been recently demonstrated in many pathological conditions. Endothelial progenitor cells (EPCs) localize at sites of ischemia and stimulate neovasculogenesis. This small study was carried out to assess whether selective blood sampling during renal angiography could demonstrate an arterio-venous gradient of EPCs in 5 patients with renal artery stenosis. Surprisingly, we found that EPCs were more abundant in venous than in arterial blood, suggesting that the kidney subjected to chronic ischemia may become a source rather than a target of EPCs.

Endothelium, Vascular↗