title: FOXO4-knockdown suppresses oxidative stress-induced apoptosis of early pro-angiogenic cells and augments their neovascularization capacities in ischemic limbs.
abstract: The effects of therapeutic angiogenesis by intramuscular injection of early pro-angiogenic cells (EPCs) to ischemic limbs are unsatisfactory. Oxidative stress in the ischemic limbs may accelerate apoptosis of injected EPCs, leading to less neovascularization. Forkhead transcription factor 4 (FOXO4) was reported to play a pivotal role in apoptosis signaling of EPCs in response to oxidative stress. Accordingly, we assessed whether FOXO4-knockdown EPCs (FOXO4KD-EPCs) could suppress the oxidative stress-induced apoptosis and augment the neovascularization capacity in ischemic limbs. We transfected small interfering RNA targeted against FOXO4 of human EPCs to generate FOXO4KD-EPCs and confirmed a successful knockdown. FOXO4KD-EPCs gained resistance to apoptosis in response to hydrogen peroxide in vitro. Oxidative stress stained by dihydroethidium was stronger for the immunodeficient rat ischemic limb tissue than for the rat non-ischemic one. Although the number of apoptotic EPCs injected into the rat ischemic limb was greater than that of apoptotic EPCs injected into the rat non-ischemic limb, FOXO4KD-EPCs injected into the rat ischemic limb brought less apoptosis and more neovascularization than EPCs. Taken together, the use of FOXO4KD-EPCs with resistance to oxidative stress-induced apoptosis may be a new strategy to augment the effects of therapeutic angiogenesis by intramuscular injection of EPCs.
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Takaharu
authors.initials: T
authors.lastname: Nakayoshi
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan; The Cardiovascular Research Institute, Kurume University, Fukuoka, Japan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Sasaki
authors.affiliation: The Cardiovascular Research Institute, Kurume University, Fukuoka, Japan.
authors.forename: Hidemi
authors.initials: H
authors.lastname: Kajimoto
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koiwaya
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Ohtsuka
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Ueno
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Chibana
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Itaya
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Yokoyama
authors.affiliation: Division of Cardio-Vascular Medicine, Department of Internal Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fukumoto
authors.affiliation: International University of Health and Welfare, Fukuoka, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Imaizumi
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D017209:Apoptosis; D018797:Cell Cycle Proteins; D016207:Cytokines / Q000378:metabolism; D005260:Female; D051858:Forkhead Transcription Factors / Q000172:deficiency* / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics; D055785:Gene Knockdown Techniques; D006614:Hindlimb / Q000098:blood supply*; D006801:Humans; D007511:Ischemia / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D018919:Neovascularization, Physiologic; D018384:Oxidative Stress; D010641:Phenotype; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D014157:Transcription Factors / Q000172:deficiency* / Q000235:genetics
chemical_list: D018797:Cell Cycle Proteins; D016207:Cytokines; C108803:FOXO4 protein, human; C524737:FOXO4 protein, rat; D051858:Forkhead Transcription Factors; D017382:Reactive Oxygen Species; D014157:Transcription Factors