Purpose: To prospectively test in a porcine model the hypothesis that bariatric embolization with commercially available calibrated microspheres can result in substantial suppression of systemic ghrelin levels and affect weight gain over an 8-week period.
Materials and methods: The institutional animal care and use committee approved this study. Twelve healthy growing swine (mean weight, 38.4 kg; weight range, 30.3-47.0 kg) were evaluated. Bariatric embolization was performed by infusion of 40-μm calibrated microspheres selectively into the gastric arteries that supply the fundus. Six swine underwent bariatric embolization, while six control animals underwent a sham procedure with saline. Weight and fasting plasma ghrelin and glucose levels were obtained in animals at baseline and at weeks 1-8. Statistical testing for differences in serum ghrelin levels and weight at each time point was performed with the Wilcoxon signed rank test for intragroup differences and the Wilcoxon rank sum test for intergroup differences.
Results: The pattern of change in ghrelin levels over time was significantly different between control and experimental animals. Weekly ghrelin levels were measured in control and experimental animals as a change from baseline ghrelin values. Average postprocedure ghrelin values increased by 328.9 pg/dL ± 129.0 (standard deviation) in control animals and decreased by 537.9 pg/dL ± 209.6 in experimental animals (P = .004). The pattern of change in weight over time was significantly different between control and experimental animals. The average postprocedure weight gain in experimental animals was significantly lower than that in control animals (3.6 kg ± 3.8 vs 9.4 kg ± 2.8, respectively; P = .025).
Conclusion: Bariatric embolization can significantly suppress ghrelin and significantly affect weight gain. Further study is warranted before this technique can be used routinely in humans.