Perioperative treatment with human growth hormone down-regulates apoptosis and increases superoxide production in PMN from patients undergoing infrarenal abdominal aortic aneurysm repair

Abstract

Background Recombinant human growth hormone (hGH) therapy has a beneficial effect on catabolism and wound healing after major surgery. Polymorphonuclear neutrophils (PMN) play an important role in this context. In a prospective, double-blind, randomized, placebo-controlled trial we studied the effect of perioperative hGH treatment on postoperative wound healing and on changes in superoxide generation and susceptibility to apoptosis of PMN in elderly patients undergoing elective abdominal aortic aneurysm repair. Methods Seven patients were treated with high-dose hGH (16 U/d) for nine days, seven patients with a placebo. IGF-I, neutrophil count, O 2-production induced by opsonized zymosan and apoptosis of PMN were measured and correlated with clinical outcome. Results Perioperative hGH treatment more than doubled the O 2 - production in PMN before and 24 h after surgery ( p < 0.01). The long-term capacity of PMN to generate O 2 in vitro was prolonged ( p < 0.001) in the hGH group. Spontaneous and Fas-inducible apoptosis was strongly down-regulated in PMN after surgery in all patients ( p < 0.01). hGH-treatment distinctly reduced apoptosis in PMN before and after surgery ( p < 0.01). Clinical outcome was similar in both groups. Conclusion Perioperative hGH treatment results in an enhanced O 2 - production in PMN and in a prolongation of the functional life span of these cells. This may improve immune function and help to overcome the postoperative anergic state of the immune system especially in elderly individuals.