Abstract 9385: Percutaneous Carbon Dioxide Treatment Using a Gas Mist Generator Accelerates Angiogenesis in the Ischemic Hindlimb
Background: Although highly-concentrated carbon dioxide (CO2) is thought to be useful for ischemic diseases, devising an artificial CO2-rich bath is difficult. Hypothesis: We hypothesized that the treatment with a few micrometers of CO2 particles atomized by double-fluid nozzles (CO2 mist) would exert an angiogenic effect in the ischemic hindlimb.
Methods and Results: (1) Lower bodies of rats with unilateral hindlimb ischemia were wrapped in a polyethylene bag filled with CO2 gas alone or CO2 mist by a gas mist generator (Advance Biotron). Near-infrared spectroscopy revealed that CO2 mist-treatment increased oxygenated hemoglobin and decreased deoxygenated hemoglobin in the ischemic leg of rats. However, CO2 gas-treatment did not change these parameters. (2) Mice with unilateral hindlimb ischemia were divided into the untreated (UT) group and CO2 mist-treated (CM) group. CO2 mist was treated to mice in the same way as rats for 10 minutes a day. By a laser Doppler analysis, ischemic hindlimb blood flow in the CM group was higher persistently after 7th days of induction of ischemia than that in the UT group. Furthermore, capillary density by immunostaining with anti-CD31 was also significantly increased in the CM group at day 28, compared with the UT group. These effects were abolished by administration of Nω-Nitro-L-arginine, an inhibitor of nitric oxide synthase. Vascular endothelial growth factor mRNA expression at days 4 and 7 was increased in the CM group but not in the UT group. (3) At 4 days after ischemia, digested proteins of muscles from the nonischemic, UT or CM group were labeled with isobaric tag for relative and absolute quantitation (iTRAQ) reagents, and proteomic analysis was performed by liquid chromatography - tandem Mass spectrometry (LC/MS/MS). Sixty-eight and 62 of identified 195 proteins were increased and decreased by ischemia, respectively. The treatment of CO2 mist downregulated some of the 68 increased proteins, which were mainly signal transduction-related proteins. On the other hand, CO2 mist-treatment upregulated some of the 62 decreased proteins, which were mainly metabolic enzyme-related proteins.
Conclusion: Percutaneous CO2 mist therapy may be a potentially useful for ischemia-induced angiogenesis.
- © 2012 by American Heart Association, Inc.