Discovery And Pharmacological Studies Of NE-2001, A Novel Chemical Entity Directed Against Helicobacter Pylori

Helicobacter pylori is a kind of gram-negative bacterium which colonies themucous layer of human stomach and infects half the world's population. It is widelyaccepted that eradication of Helicobacter pylori plays an important role in treatinggastritis and gastric ulcer, and reducing incidences of stomach cancer.NE-2001 is a new chemical entity with independent intellectual property rightsdiscovered and developed in China. Major contents of this thesis include: (1) Tosystematically investigate the antimicrobial activities of NE-2001 directed againstHelicobacter pylori standard strains and clinical strains from different sources,especially drug-resistant strains common in clinics. (2) Developing a formulationusing inclusion technology based on 2-hydroxypropyl-β-cyclodextrin, in order toimprove the poor water solubility of NE-2001. The inclusion compound was testedin vivo for anti-Helicobacter pylori effect. (3) Establishing a high-throughputscreening assay targeting leucyl aminopeptidase from Helicobacter pylori. It wasapplied subsequently to large-scale screening of a compound library at the NationalCenter for Drug Screening.Conclusions: (1) According to two independent in vitro susceptibility testsconsisting of 24 clinical isolates of Helicobacter pylori randomly collected fromRenji Hospital and Jiangsu People's Hospital and 13 isolates resistant tometronidazole and/or clarithromycin selected from 50 clinical isolates respectively,NE-2001 showed significant inhibitory effects on the clinical isolates, implying thatNE-2001 is of value for further research. (2) A water soluable formulation techniquewas validated for NE-2001 using 2-hydroxypropyl-β-cyclodextrin. The inclusioneffect was confirmed by X-ray diffraction and differential scanning calorimetry.C57BL/6 mice were infected with Helicobacter pylori (SS1) and treated orally withNE-2001 along. A moderate eradication effect was observed thereafter. Tripletherapy regimen that combining NE-2001 with two other antimicrobial agents iscurrently under investigation. (3) A high-throughput screening assay based on leucylaminopeptidase was set up and applied to large-scale screening of 32000 compounds.As a result, several inhibitors were identified and one of which displayedantimicrobial property against Helicobacter pylori. Relevant structure-activityrelationship studies has been initiated.