Circulatory Rejuvenated EPCs Derived from PAOD Patients Treated by CD34+ Cells and Hyperbaric Oxygen Therapy Salvaged the Nude Mouse Limb against Critical Ischemia.

This study tested whether circulatory endothelial progenitor cells (EPCs) derived from peripheral arterial occlusive disease (PAOD) patients after receiving combined autologous CD34+ cell and hyperbaric oxygen (HBO) therapy (defined as rejuvenated EPCs) would salvage nude mouse limbs against critical limb ischemia (CLI). Adult-male nude mice (n = 40) were equally categorized into group 1 (sham-operated control), group 2 (CLI), group 3 (CLI-EPCs (6 × 105) derived from PAOD patient's circulatory blood prior to CD34+ cell and HBO treatment (EPCPr-T) by intramuscular injection at 3 h after CLI induction) and group 4 (CLI-EPCs (6 × 105) derived from PAOD patient's circulatory blood after CD34+ cell and HBO treatment (EPCAf-T) by the identical injection method). By 2, 7 and 14 days after the CLI procedure, the ischemic to normal blood flow (INBF) ratio was highest in group 1, lowest in group 2 and significantly lower in group 4 than in group 3 (p < 0.0001). The protein levels of endothelial functional integrity (CD31/von Willebrand factor (vWF)/endothelial nitric-oxide synthase (eNOS)) expressed a similar pattern to that of INBF. In contrast, apoptotic/mitochondrial-damaged (mitochondrial-Bax/caspase-3/PARP/cytosolic-cytochrome-C) biomarkers and fibrosis (Smad3/TGF-ß) exhibited an opposite pattern, whereas the protein expressions of anti-fibrosis (Smad1/5 and BMP-2) and mitochondrial integrity (mitochondrial-cytochrome-C) showed an identical pattern of INBF (all p < 0.0001). The protein expressions of angiogenesis biomarkers (VEGF/SDF-1α/HIF-1α) were progressively increased from groups 1 to 3 (all p < 0.0010). The number of small vessels and endothelial cell surface markers (CD31+/vWF+) in the CLI area displayed an identical pattern of INBF (all p < 0.0001). CLI automatic amputation was higher in group 2 than in other groups (all p < 0.001). In conclusion, EPCs from HBO-C34+ cell therapy significantly restored the blood flow and salvaged the CLI in nude mice.

Hyperbaric oxygen facilitates the effect of endothelial progenitor cell therapy on improving outcome of rat critical limb ischemia.

We tested the hypothesis that hyperbaric oxygen (HBO) (100% oxygen/2.4 atmospheres) facilitated the effect of autologous endothelial progenitor cell (EPC) therapy on restoring the blood flow in rat critical-limb ischemia (CLI). Adult-male-SD rats (n = 8/each group) were categorized into group 1 [sham control (SC)], group 2 (CLI-treated with culture medium), group 3 [CLI-intermittent HBO (3 h/day for 5 consecutive days after CLI), group 4 (CLI-EPC/2.0 × 106 cells), and group 5 (CLI-HBO-EPC). By day 5 after CLI, flow cytometry showed that the circulating EPC (Sca-1/CD31+/C-kit/CD31+/CD34+) levels were highest in group 5 and lowest in group 2 (all P < 0.001). By day 14, laser Doppler demonstrated that the ratio of blood flow (i.e., CLI to normal hind-limb) was highest in group 1, lowest in group 2 and significantly higher in group 5 than in groups 3 and 4 (all P < 0.0001). The protein expressions of endothelial-cell biomarkers (CD31/vWF/eNOS), and numbers of endothelial-cell markers (CD31+/vWF+) and small vessels exhibited a similar pattern to blood-flow ratio among five groups, whereas the angiogenesis parameters in protein (CXCR4/SDF-1α/HIF-1α/VEGF) and cellular (HIF-1α/SDF-1α/CXCR4+) levels were progressively increased from groups 1 to 5 (all P < 0.0001). The protein expression of apoptotic (mitochondrial-Bax/cleaved-capspase-3/PARP), fibrotic (p-Smad3/TGF-ß) and mitochondrial-damaged (cytosolic-cytochrome C) exhibited an opposite pattern, whereas the protein expressions of anti-fibrotic (BMP-2/p-Smad1/5) and mitochondrial integrity (mitochondrial-cytochrome C) exhibited an identical pattern of ratio of blood flow among the five groups (all P < 0.0001). Combined HBO-EPC therapy is superior to either one alone in improving ischemia in rodent CLI.

Hyperbaric Oxygen Therapy Enhanced Circulating Levels of Endothelial Progenitor Cells and Angiogenesis Biomarkers, Blood Flow, in Ischemic Areas in Patients with Peripheral Arterial Occlusive Disease.

BACKGROUND: This study tested the hypothesis that hyperbaric oxygen (HBO) therapy enhanced the circulating levels of endothelial progenitor cells (EPCs), soluble angiogenesis factors, and blood flow in ischemic areas in patients with peripheral arterial occlusive disease (PAOD). METHODS: In total, 57 consecutive patients with PAOD undergoing the HBO therapy (3 atmospheres (atm) for 2 h each time) were prospectively enrolled into the present study. Venous blood sampling was performed to assess the circulating levels of EPCs and soluble angiogenesis factors prior to and during five sessions of HBO therapy. Additionally, skin perfusion pressure (SPP), an indicator of blood flow in ischemic areas, was measured by moorVMS-PRES. RESULTS: The results demonstrated that the circulating levels of EPCs (cluster of differentiation (CD)34⁺/CD133⁺/CD45dim, CD31⁺/CD133⁺/CD45dim, CD34⁺) and soluble angiogenesis factors-vascular endothelial growth factor/stromal cell-derived factor 1/hepatocyte growth factor/fibroblast growth factor (VEGF/SDF-1α/HGF/FGF) were significantly increased post-HBO therapy as compared to pre-HBO therapy (all p < 0.01). Additionally, Matrigel assay showed that the angiogenesis was significantly increased in post-HBO therapy as compared to prior to therapy (p < 0.001). Furthermore, SPP was significantly increased in the ischemic area (i.e., plantar foot and mean SPP of the ischemic foot) in post-HBO therapy as compared to pre-HBO therapy (all p < 0.01). Importantly, the HBO therapy did appear to result in complications, and all the patients were uneventfully discharged without amputation. CONCLUSIONS: HBO therapy augmented circulating levels of EPCs and angiogenesis factors, and improved the blood flow in the ischemic area.