Published online Apr 21, 2013. doi: 10.3748/wjg.v19.i15.2388
Revised: April 8, 2013
Accepted: April 9, 2013
Published online: April 21, 2013
AIM: To investigate changes in serum ghrelin and obestatin levels before and after Helicobacter pylori (H. pylori) eradication.
METHODS: A total of 92 patients presenting with symptoms of dyspepsia were enrolled in the study. Upper endoscopy was performed on all patients and used to diagnose H. pylori infection according to the presence of characteristic histopathological findings; seventy patients were diagnosed with H. pylori infection and the remaining 22 non-infected patients were classified as healthy controls. H. pylori eradication was accomplished by administering the classical triple therapy drug regimen, consisting of lansoprazole 30 mg bid, amoxicillin 1 g bid, and clarithromycin 500 mg tid for 14 d. The eradication of H. pylori was assessed with C14-urea breath test, which was performed at eight weeks after treatment. Levels of serum active ghrelin and obestatin were assessed at beginning of the study (prior to treatment) and after eight weeks. The levels were comparatively analyzed between the H. pylori negative control group, the H. pylori eradicated group, and the H. pylori non-eradicated group.
RESULTS: A total of 92 patients, 50 females and 42 males with a mean age of 38.2 ± 11.9 years (range: 19-64), were analyzed. H. pylori eradication success was achieved in 74.3% (52/70) of H. pylori positive patients. The initial levels of ghrelin in the H. pylori positive and control cases were 63.6 ± 19.8 pg/mL and 65.1 ± 19.2 pg/mL (P = 0.78), respectively, and initial obestatin levels were 771 ± 427 pg/mL and 830 ± 296 pg/mL (P = 0.19), respectively. The difference between the initial levels and the week 8 levels of ghrelin and obestatin in the control group was insignificant [4.5% (P = 0.30) and -0.9% (P = 0.65), respectively]. The difference between the initial and week 8 levels of ghrelin and obestatin in the H. pylori non-eradicated group were also insignificant [0.9% (P = 0.64) and 5.3% (P = 0.32), respectively]. The H. pylori eradicated group had a greater change in obestatin levels when compared to the control and the non-eradicated groups (148 ± 381 pg/mL vs -12 ± 138 pg/mL and -72.8 ± 203 pg/mL, respectively, P = 0.015), while decreases in ghrelin levels were insignificant (-7.2 pg/mL vs -1.4 pg/mL and -1.9 pg/mL, respectively, P = 0.52). The ghrelin/obestatin ratio for the initial and week 8 levels changed significantly in only the H. pylori eradicated group (0.11 vs 0.08, respectively, P = 0.015). For overweight patients (as designated by body mass index), we observed significant increases in obestatin levels in the eradicated group as compared to non-eradicated group (201 ± 458 pg/mL vs -5 ± 81 pg/mL, respectively, P = 0.02). In the H. pylori-eradicated group, the levels did not differ between the sexes for ghrelin (-6.3 ± 26.9 pg/mL vs -8.0 ± 24.0 pg/mL, respectively, P = 0.97) or obestatin (210 ± 390 pg/mL vs 96 ± 372 pg/mL, respectively, P = 0.23).
CONCLUSION: Serum levels of ghrelin decreased while obestatin levels increased in H. pylori eradicated subjects, especially in overweight and male patients.
Core tip: Ghrelin and obestatin are peptides that have opposing roles in the regulation of appetite and satiety. Helicobacter pylori (H. pylori), a common cause of gastric inflammation, may have important effects on these peptides and in turn be a potential target of anti-obesity strategies. While the interplay between H. pylori and these peptides are well studied, this study included two novel approaches. First, we collected serum samples at two separate time points for both the experimental and control groups, eliminating potential seasonal problems. Second, we focused on not only to H. pylori positive patients that responded to therapy, but also those who did not. This helped to distinguish the effects of antibiotherapy on ghrelin and obestatin regardless of the effectiveness of H. pylori treatment.