The Suppressive Effects of Geniposide and Genipin on Helicobacter pylori Infections In Vitro and In Vivo

Geniposide and genipin have been found in Gardenia jasminoides Ellis, a traditional Chinese medicine that exhibits multiple biological functions. However, no report showing the effects of geniposide and genipin on gastric protection in Helicobacter pylori infections in vitro and in vivo has been done. In this study, we clarified how geniposide and genipin suppress H. pylori‐mediated inflammation in gastric AGS cells and C57BL/6 mice. Our results demonstrated that genipin shows a strong ability to inhibit H. pylori growth and is able to reduce vacA and cagA gene expression of H. pylori in infected AGS cells. Genipin also attenuates the abilities of adhesion and invasion of H. pylori to AGS cells. An attenuation of interleukin (IL)‐8 and IFN‐γ production caused by genipin was observed to inhibit cell inflammatory responses. In the in vivo experiments, geniposide and genipin both showed suppressive effects on the vacA gene expression in mice after H. pylori infection. The serum levels of IFN‐γ, IL‐1β, immunoglobulin A, and Immunoglobulin M were decreased by geniposide and genipin in infected mice. The inflammatory maker COX2 was downregulated in H. pylori‐infected mice after exposure to geniposide and genipin. Together, geniposide and genipin effectively exert a healthy promotion to reduce H. pylori infections in vivo by interfering with the growth and virulence of H. pylori as well as attenuating the gastric inflammation caused by an H. pylori infection. Practical Application Geniposide and genipin have a healthy promotion to eradicate H. pylori infections by interfering with the growth and virulence of H. pylori and to attenuate the gastric inflammation caused by an H. pylori infection.