Cystic adventitial disease of the popliteal artery presenting with features of entrapment syndrome

Cystic adventitial disease is an uncommon cause of lower extremity claudication resulting from accumulation of mucinous fluid in an arterial subadventitial layer, typically of the popliteal artery. A popliteal bruit and/or reduced distal pulses with knee flexion may be seen on examination. Alternatively, popliteal artery entrapment syndrome triggers claudication via an aberrant arterial pathway or muscular hypertrophy. Decreased distal pressures with plantar or dorsiflexion is a key finding. This report details the case of a middle-aged male with cystic adventitial disease whose diagnosis was complicated by concurrent features of popliteal artery entrapment syndrome. Treatment consisted of venous interposition grafting, which yielded excellent results.

Targeted gene deletion of prolyl hydroxylase domain protein 3 triggers angiogenesis and preserves cardiac function by stabilizing hypoxia inducible factor 1 alpha following myocardial infarction

The key oxygen sensing molecules, Prolyl-hydroxylase domain 1-3 enzymes (PHD1-3), regulate hypoxia-inducible factor (HIF) under hypoxia. In the settings of cardiomyopathy and ischemia-reperfusion injury, PHD3 expression is elevated, resulting in decreased HIF activation. The role of PHD3 in myocardial injury is poorly understood. Hence, we aimed to determine the effects of PHD3 deletion in mice on HIF-1α and other related pathways following myocardial infarction (MI). Left coronary artery (LAD) in both wild type and prolyl hydroxylase 3 knock out (PHD3⁻/⁻) mice was ligated to induce myocardial infarction. Electrophoretic mobility shift analysis showed significant increase in DNA-binding activity of HIF-1α in PHD3⁻/⁻ mice as compared to wild type (WT) mice post MI. The PHD3⁻/⁻MI group also showed decreased fibrosis. Seven days after MI, enhanced capillary/arteriolar density was observed compared to WTMI group. PHD3⁻/⁻ mice subjected to MI also showed improved cardiac functions (Ejection fraction and Fractional shortening), as assessed by echocardiogram, compared to WT. Western blot analysis showed increased VEGF, Ang-1 & Bcl-2 expression in PHD3⁻/⁻MI group. In conclusion, ablation of the PHD3 gene resulted in increased angiogenesis and cardiac function after infarction thereby offering a potential target for pharmacological management of ischemic myocardial disease.

Disruption of hypoxia-inducible transcription factor-prolyl hydroxylase domain-1 (PHD-1-/-) attenuates ex vivo myocardial ischemia/reperfusion injury through hypoxia-inducible factor-1α transcription factor and its target genes in mice

Hypoxia-inducible transcription factor (HIF)-prolyl hydroxylases domain (PHD-1-3) are oxygen sensors that regulate the stability of the HIFs in an oxygen-dependent manner. Suppression of PHD enzymes leads to stabilization of HIFs and offers a potential treatment option for many ischemic disorders, such as peripheral artery occlusive disease, myocardial infarction, and stroke. Here, we show that homozygous disruption of PHD-1 (PHD-1(-/-)) could facilitate HIF-1α-mediated cardioprotection in ischemia/reperfused (I/R) myocardium. Wild-type (WT) and PHD-1(-/-) mice were randomized into WT time-matched control (TMC), PHD-1(-/-) TMC (PHD1TMC), WT I/R, and PHD-1(-/-) I/R (PHD1IR). Isolated hearts from each group were subjected to 30 min of global ischemia followed by 2 h of reperfusion. TMC hearts were perfused for 2 h 30 min without ischemia. Decreased infarct size (35%±0.6% vs. 49%±0.4%) and apoptotic cardiomyocytes (106±13 vs. 233±21 counts/100 high-power field) were observed in PHD1IR compared to wild-type ischemia/reperfusion (WTIR). Protein expression of HIF-1α was significantly increased in PHD1IR compared to WTIR. mRNA expression of β-catenin (1.9-fold), endothelial nitric oxide synthase (1.9-fold), p65 (1.9-fold), and Bcl-2 (2.7-fold) were upregulated in the PHD1IR compared with WTIR, which was studied by real-time quantitative polymerase chain reaction. Further, gel-shift analysis showed increased DNA binding activity of HIF-1α and nuclear factor-kappaB in PHD1IR compared to WTIR. In addition, nuclear translocation of β-catenin was increased in PHD1IR compared with WTIR. These findings indicated that silencing of PHD-1 attenuates myocardial I/R injury probably by enhancing HIF-1α/β-catenin/endothelial nitric oxide synthase/nuclear factor-kappaB and Bcl-2 signaling pathway.