Local angioneogenetic effect of intramuscular interleukin-8 injection

Abstract

Objective: Angioneogenesis, which plays significant roles in a variety of physiological processes such as embryonic growth and wound healing, is strictly delimited and is finely tuned by a balance of proangiogenic and antiangiogenic factors. This study was conducted to investigate the angioneogenic effect of interleukin-8 (IL-8) administered intramuscularly. Material and Methods: Twelve New Zealand white rabbits were included in this study. A total daily dose of 4 micrograms (1 mcg/kg) of IL-8 was administered into the left (Group A) and saline solution into the right (Group B) gluteus maximus muscles of 6 rabbits for 6 days. The remaining 6 rabbits constituted the sham group (Group C). Gluteal muscle samples were obtained from injection sites in all groups and were stained with hematoxylin-eosin and immunohistochemically by using streptavidin biotin method with CD31 antibody. Avidin-biotin peroxidase method (LSAB) was used as secondary and binding antibody. Diaminobenzidine tetrahydrochloride (DAB) was used as chromogenic substance. In immunohistochemical staining with CD31, vascular channels covered with brown stained cells or cell clusters were considered and were counted as vascular network. Results: Three subjects in Group A and one subject in Group B displayed findings of large muscle necrosis and regeneration. Vascular channel score was significantly higher in Group A (p=0.032) (Group A; median=12.5, min=6, max=16. Group B; median=5, min=4, max=13. Group C; median=4.5, min=4, max=13.) than in the other groups. Conclusion: IL-8 chemokine family seems to stimulate angioneogenesis in rabbit skeletal muscles. This result is promising in terms of the possible therapeutic potential of IL-8. Daily administration at a dose of around 1 mcg/kg caused local tissue necrosis, hence use of alternative routes such as intraarterial administration must be investigated to avoid such complications. © 2012 by Türkiye Klinikleri.