Endothelial Progenitor Cells May Be Related to Major Amputation after Angioplasty in Patients with Critical Limb Ischemia

BACKGROUND

Critical limb ischemia represents an advanced stage of peripheral arterial disease. Angioplasty improves blood flow to the limb; however, some patients progress irreversibly to lower limb amputation. Few studies have explored the predictive potential of biomarkers during postangioplasty outcomes.

AIM

To evaluate the behavior of endothelial progenitor cells in patients with critical limb ischemia, in relation to their postangioplasty outcome.

METHODS

Twenty patients with critical limb ischemia, candidates for angioplasty, were enrolled. Flow-mediated dilation, as well as endothelial progenitor cells (subpopulations CD45+/CD34+/CD133+/CD184+ and CD45+/CD/34+/KDR[VEGFR-2]+ estimated by flow cytometry) from blood flow close to vascular damage, were evaluated before and after angioplasty. Association with lower limb amputation during a 30-day follow-up was analyzed.

RESULTS

Endothelial progenitor cells were related with flow-mediated dilation. A higher number of baseline EPCs CD45⁺CD34⁺KDR⁺, as well as an impaired reactivity of endothelial progenitor cells CD45⁺CD34⁺CD133⁺CD184⁺ after angioplasty, were observed in cases further undergoing major limb amputation, with a significant discrimination ability and risk (0.75, specificity 0.83 and RR 4.5 p < 0.05).

CONCLUSIONS

Endothelial progenitor cells were related with endothelial dysfunction, whereas a higher baseline number of the subpopulation CD45⁺CD34⁺KDR⁺, as well as an impaired reactivity of subpopulation CD45⁺CD34⁺CD133⁺CD184⁺ after angioplasty, showed a predictive ability for major limb amputation in patients with critical limb ischemia.

Enlarged adipocytes from subcutaneous vs. visceral adipose tissue differentially contribute to metabolic dysfunction and atherogenic risk of patients with obesity

Morphological characteristics and source of adipose tissue as well as adipokines may increase cardiometabolic risk. This study aimed to explore whether adipose tissue characteristics may impact metabolic and atherogenic risks. Subcutaneous Adipose Tissue (SAT), Visceral Adipose Tissue (VAT) and peripheral blood were obtained from obese patients submitted to bariatric surgery. Adipose tissue (morphometry), plasma adiponectin, TNF-α, resistin (multiplexing) and biochemical chemistry were analyzed; as well as endothelial dysfunction (Flow Mediated Dilation, FMD) and atherogenesis (Carotid Intima Media Thickness, CIMT). Subgroups divided by adipocyte size and source were compared; as well as correlation and multivariate analysis. Sixty patients 36.6% males, aged 44 years-old, BMI 46.7 kg/m² were included. SAT's adipocytes showed a lower range of size expandability than VAT's adipocytes. Independent from their source, larger adipocytes were associated with higher glucose, lower adiponectin and higher CIMT. Particularly, larger adipocytes from SAT were associated with higher blood pressure, lower insulin and HDL-cholesterol; and showed positive correlation with glucose, Hb_A1c, systolic/diastolic values, and negatively correlated with insulin and adiponectin. VAT's larger adipocytes particularly associated with lower resistin and lower FMD values. Gender and Diabetes Mellitus significantly impacted the relation of adipocyte size/source with the metabolic and atherogenic risk. Multivariable analysis suggested hypertension-resistin-Hb_A1c interactions associated with SAT's larger adipocytes; whereas potential insulin-adiponectin associations were observed for VAT's larger adipocytes. Adipocyte morphology and source are differentially related with cardiometabolic and atherogenic risk in population with obesity, which are potentially affected by gender and Diabetes Mellitus.

Predicting Amputation using Local Circulating Mononuclear Progenitor Cells in Angioplasty-treated Patients with Critical Limb Ischemia

Critical limb ischemia (CLI) represents an advanced stage of the peripheral arterial disease. Angioplasty improves the blood flow to the lower limb; however, some patients irreversibly progress to limb amputation. The extent of vascular damage and the mechanisms of vascular repair are factors affecting post-angioplasty outcome. Mononuclear Progenitor Cells (MPCs) are reactive to vascular damage and repair, with the ability to reflect vascular diseases. The present protocol describes quantification of MPCs obtained from blood circulation from vessel close to the angioplasty site, as well as its relationship with endothelial dysfunction and its predictive ability for limb amputation in the next 30 days after angioplasty in patients with CLI.