Abstract

Plants used in popular diet were studied for anti-Helicobacter pylori activity and their effect on the expression of interleukin-8 (IL-8) from H. pylori infected gastric epithelial cells. Extracts were prepared of Allium sativum (A. sativum), Cuminum cyminum (C. cyminum),Piper nigrum (P. nigrum) and their mix in two different dilutions. AGS cell line and H. pyloristrains were used for co-culture experiments. Extracts bactericidal activity was determined by a viable colony count. ELISA (Enzyme linked immunosorbent assay) was used to determine IL-8 expression. DNA extracted from bacterial cells was used for polymerase chain reaction (PCR) of cytotoxin-associated gene (cagA) and E (cagE). Results revealedH. pylori strains sensitivity to A. sativum (5.5 mg/ml) was 57% (39/69) (p=0.06), and to 11 mg/ml was 65% (45/69) (p=0.02) compared to amoxicillin, respectively. CagE positive H. pylori, 37% (11/30) (p=0.02) were sensitive to plant mixture (23.5 mg/ml), 60% (18/30) (p<0.001) to plant mix (47 mg/ml), respectively. The expression of IL-8 by AGS cells treated with plant mix, (P=0.0037), C. cyminum (P<0.0001), P. nigrum (P=0.0046) and A. sativum(P=0.0021), respectively compared to positive and negative controls. Thus, dietary plants demonstrated an anti-H. pylori effect. They reduced IL-8 expression from the H. pyloriinfected AGS cells.

Key words: Helicobacter pylori; Allium sativum, Cuminum cyminum, Piper nigrum, gastric epithelial cells, interleukin-8, ELISA, cagA, cagE.