iridoids and Helicobacter-Infections

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.. 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.

Topics: Animals; Drugs, Chinese Herbal; Gardenia; Gastric Mucosa; Helicobacter Infections; Helicobacter pylori; Humans; Inflammation Mediators; Iridoids; Male; Mice; Mice, Inbred C57BL

Helicobacter pylori is a significant human pathogen that recognizes specific carbohydrate receptors, such as the fucose receptor, and produces the vacuolating cytotoxin, which induces inflammatory responses and modulates the cell-cell junction integrity of the gastric epithelium. The clinical applicability of topical antimicrobial agents was needed to complete the eradication of H. pylori in the infected fundal area. In the present study, we combined fucose-conjugated chitosan and genipin-cross-linking technologies in preparing multifunctional genipin-cross-linked fucose-chitosan/heparin nanoparticles to encapsulate amoxicillin of targeting and directly make contact with the region of microorganism on the gastric epithelium. The results show that the nanoparticles effectively reduced drug release at gastric acids and then released amoxicillin in an H. pylori survival situation to inhibit H. pylori growth and reduce disruption of the cell-cell junction protein in areas of H. pylori infection. Furthermore, with amoxicillin-loaded nanoparticles, a more complete H. pylori clearance effect was observed, and H. pylori-associated gastric inflammation in an infected animal model was effectively reduced.

Topics: Amoxicillin; Animals; Cell Line; Cell Survival; Chitosan; Coculture Techniques; Cross-Linking Reagents; Fluorescent Antibody Technique; Fucose; Helicobacter Infections; Helicobacter pylori; Heparin; Humans; Hydrogen-Ion Concentration; Iridoids; Male; Mice; Mice, Inbred C57BL; Microbial Sensitivity Tests; Nanoparticles; Particle Size; Spectroscopy, Fourier Transform Infrared; Static Electricity

Helicobacter pylori (H. pylori) colonizes the gastric mucosa of over 50% of the world population, causing several pathologies, such as gastric ulcers and gastric cancer. Since current antibiotic treatments are inefficient in 20% of cases alternative therapies are needed. This work reports the ability of chitosan microspheres to adhere to H. pylori and prevent/remove H. pylori colonization. Adhesion of H. pylori strains with different functional adhesins (BabA and/or SabA) to chitosan microspheres (diameter 167 ± 27 μm) occurs at both pH 2.6 and 6.0, but is higher at pH 6.0. Bacterial adhesion to a gastric cell line expressing sialylated carbohydrates (SabA receptors) was performed at the same pH values using H. pylori strains with and without SabA. At both pH values addition of microspheres to gastric cells before and after pre-incubation with H. pylori decreased bacterial adhesion to cells. Furthermore, the chitosan microspheres were non-cytotoxic. These findings reveal the potential of chitosan microspheres as an alternative or complementary treatment for H. pylori gastric eradication or prevention of H. pylori colonization.

Topics: Adhesins, Bacterial; Animals; Bacterial Adhesion; Cell Line, Tumor; Cell Survival; Chitosan; Cross-Linking Reagents; Fluorescein-5-isothiocyanate; Gastric Mucosa; Helicobacter Infections; Helicobacter pylori; Humans; Hydrogen-Ion Concentration; Iridoids; Microscopy, Electron, Scanning; Microspheres; Particle Size

In this study we investigated the effects of Gardenia jasminoides Ellis (GJE) extract and its constituents, such as ursolic acid and genipin, on gastritis in rats and the growth of human gastric cancer cells. The GJE extract, ursolic acid and genipin showed the acid-neutralizing capacities, the antioxidant activities, and the inhibitory effects on the growth of Helicobacter pylori (H. pylori), which are almost equivalent to positive control compounds. In addition, the GJE extract and ursolic acid had cytotoxic activity against AGS and SUN638 gastric cancer cells. The genipin and ursolic acid inhibited significant HCl/ethanol-induced gastric lesions. Taken together, GJE extract and its constituents might have antigastritic activities, associated with the antioxidant activities, acid-neutralizing capacities, and anti-H. pylori action. Also, we could suggest that genipin and ursolic acid may be useful for the treatment and/or protection of gastritis.

Topics: Animals; Anti-Ulcer Agents; Antineoplastic Agents, Phytogenic; Antioxidants; Cell Line, Tumor; Ethanol; Free Radical Scavengers; Gardenia; Gastritis; Helicobacter Infections; Helicobacter pylori; Indicators and Reagents; Iridoid Glycosides; Iridoids; Lipid Peroxidation; Male; Plant Extracts; Rats; Rats, Sprague-Dawley; Solvents; Stomach Neoplasms; Stomach Ulcer; Triterpenes; Ursolic Acid