Effects of Helicobacter pylori on endothelial cell proliferation and chemotaxis.

BACKGROUND/AIM: Helicobacter pylori is associated with an increased risk of peptic ulcer disease development and recurrence. Ulcer healing is dependent upon angiogenesis, requiring endothelial cell (EC) proliferation and chemotaxis. This study determined whether extracts of H. pylori affected EC proliferation and/or chemotaxis in vitro.

METHODS

The effects of water and broth extracts of three genotypically different strains of H. pylori and of single strains of Campylobacter jejuni and Escherichia coli on human dermal microvascular EC (HuDMEC) and human umbilical vein EC (HUVEC) were assessed. Tetrazolium dye (MTT) proliferation, dual staining cell viability, flow cytometry, and microchemotaxis assays were performed.

RESULTS

H. pylori (all strains) and C. jejuni inhibited HuDMEC (p < 0.01) and HUVEC (p < 0.01) proliferation and decreased the proportion of HUVECs in the S phase of the cell cycle. E. coli had no effect on EC proliferation. The levels of vascular endothelial growth factor stimulated chemotaxis were significantly greater (p < 0.01) than the levels of basal migration for both control and extract-treated ECs. However, none of the bacterial extracts affected EC basal migration or chemotaxis.

CONCLUSION

H. pylori extracts inhibit HuDMEC and HUVEC proliferation in vitro by a cytostatic, strain-independent mechanism. A similar antiproliferative effect of C. jejuni was observed. Our findings suggest that both H. pylori and C. jejuni have the ability to inhibit one of the key stages of angiogenesis which may have implications in peptic ulcer disease.