Intracellular delivery of Neuroglobin using HIV-1 TAT protein transduction domain fails to protect against oxygen and glucose deprivation.
Neuroglobin (Ngb) is a heme protein that is primarily localised in the retina and the brain. Its physiological role is largely unknown. It has been reported that its overexpression protects neurons from hypoxia in vitro and in vivo, suggesting that the rapid modulation of the Ngb level in the nerve cells may be a promising stroke treatment strategy. In this study, we used a novel approach to overexpress Ngb and evaluate its ability to promote neuronal survival under hypoxic conditions. We constructed a human recombinant Ngb fused to the cell penetrating peptide (CPP) derived from HIV-1 TAT. Purified recombinant TAT-Ngb was able to efficiently transduce CHO and SHSY5Y cells, when added to the culture media. The potential neuroprotective action of Ngb was then examined by using an in vitro model of ischemia. The two neuronal cell lines RGC-5 and SH-SY5Y were subjected to oxygen glucose deprivation (OGD) after pre-treatment with TAT-Ngb. In both cell types, however, the treatment with the TAT-Ngb fusion protein did not show any effect on cell viability. This discrepancy to earlier reports might be due to the experimental model for oxygen glucose deprivation we employed. Alternatively, intracellular delivery of Ngb by the TAT/CPP might not have beneficial effects in the treatment of ischemic pathology.
Peroni
Daniele
D
CRIBI Biotechnology Centre, University of Padua, Ugo Bassi 58/B, 35131 Padua, Italy. daniele@anatomy.univr.it
Negro
Alessandro
A
Bähr
Mathias
M
Dietz
Gunnar P H
GP
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D015696:Gene Products, tat / Q000502:physiology*; D005914:Globins / Q000627:therapeutic use*; D005947:Glucose / Q000172:deficiency*; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000188:drug therapy*; D009419:Nerve Tissue Proteins / Q000627:therapeutic use*; D009447:Neuroblastoma; D000078787:Neuroglobin; D017434:Protein Structure, Tertiary / Q000502:physiology; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000627:therapeutic use; D014161:Transduction, Genetic / Q000379:methods*; D054322:tat Gene Products, Human Immunodeficiency Virus
D015696:Gene Products, tat; D009419:Nerve Tissue Proteins; D000078787:Neuroglobin; D011993:Recombinant Fusion Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus; D005914:Globins; D005947:Glucose