Endothelial progenitor cells as a new agent contributing to vascular repair

Abstract

A special type of stem cells, defined as endothelial progenitor cells (EPCs), has been found in the bone marrow and peripheral blood. These EPCs are incorporated into injured vessels and become mature endothelial cells during re-endothelialization and neovascularization processes. Though a complete phenotypic description of EPCs remains unclear, these cells express several surface markers, the most relevant including CD34 and CD133 antigens. Furthermore, EPCs derived from other sources could also give rise to mature endothelial cells, which makes this group of cells more diverse. The recruitment of EPCs from the bone marrow to homing sites of vasculogenesis is subject to regulation by many factors, including chemokines and growth factors. The precise mechanism of EPC mobilization and differentiation is not entirely elucidated and is still under investigation. Recent studies have suggested that EPCs may promote local angiogenesis by secreting angiogenic growth factors in a paracrine manner. The number and function of EPCs can be affected during pathological conditions, including diabetes mellitus, cardiovascular risk factors for ischemic disease, and graft vasculopathy. Additionally, EPC number and migration capacity could be improved by such factors as drugs, physical exercise, and growth factors. Transplantation of EPCs into ischemic tissues may emerge as a promising approach in the therapy of diseases associated with blood vessel disorders.

Osteoporosis in diabetes mellitus: Possible cellular and molecular mechanisms

“…In vivo investigation in swimming rats showed higher bone capillary vascularity compared with sedentary controls [69] . Such higher vas culogenesis following exercise has been postulated to result from an increase in circulating EPCs [70,71] . Adams and colleagues demonstrated the elevation of EPC levels after singleexercise stress in patients with coronary artery disease [70] .…”

“…Adams and colleagues demonstrated the elevation of EPC levels after singleexercise stress in patients with coronary artery disease [70] . An increase in EPC level was accompanied by an elevation of plasma VEGF [70,71] , a crucial growth factor for EPC proliferation, differentiation and migration [70,71] . Thus, certain physical activities/interventions, such as appropriate endurance exercise, should improve perfusion in bone and alleviate bone loss in DM patients.…”

Urinary Vascular Endothelial Growth Factor (VEGF) as a Novel Marker for Early Prediction of Esophageal Varices in Patients with Chronic Liver Disease

“…These circulating EPOs target injured endothelial surfaces. Homing of EPOs into the sites of endothelial injury occurs where they play a role in repair and regeneration of the endothelium [30]. Thus, low VEGF levels will weaken this healing power and may lead to a higher risk of bleeding.…”

Identyfikacja i znaczenie krążących endotelialnych komórek progenitorowych u chorych na raka wątrobowokomórkowego

“…W rezultacie w krążeniu obwodowym chorych na marskość wątroby i chorych na raka wątrobowokomórkowego wzrasta odsetek endotelialnych komórek progenitorowych w subpopulacji hematopoetycznych komórek macierzystych (%EPCS/HScs), lecz jednocześnie maleje ogólnoustrojowy "potencjał angiogenezy", wyrażony odsetkiem macierzystych komórek hematopoetycznych w populacji białych krwinek (%HSCs/WBC). Przedstawione wyniki znajdują potwierdzenie w wielu innych obserwacjach, a zarazem dostarczają kolejnego dowodu wskazującego na marskość wątroby jako na stan przedrakowy [10,22,[43][44][45][46][47][48].…”

“…Właściwość ta wyraża się w obrazie klinicznym choroby poprzez zwięk-szenie krążących we krwi obwodowej komórek progenitorowych raka (CSCs), także komórek endotelialnych (EPCs). Wykrycie i oznaczenie ich populacji umożliwia rozpoznanie, ocenę stopnia zaawansowania choroby i rokowania, a także monitorowanie przebiegu i wyników leczenia [7,14,24,43,47,49,50,52]. Wyniki wielu innych badań sugestii tych nie potwierdzają [8,20,26,40,45,51].…”