No abstract

The medicinal plant Spathodea campanulata P. Beauv. (Bignoniaceae) has been traditionally applied for the prevention and treatment of diseases of the kidney and urinary system, the skin, the gastrointestinal tract, and inflammation in general. The present work shows for the first time how chemical components from this plant inhibit Helicobacter pylori growth by urease inhibition and modulation of virulence factors. The crude extract and the main fractions of S. campanulata bark were tested on H. pylori isolated strains and the active ones were further fractionated. Fractions and sub-fractions of the plant crude extract were characterized by ultra-high-performance liquid chromatographic tandem high resolution-mass spectrometry detection (UHPLC-HRMS). Several phenolics and triterpenoids were identified. Among the sub-fractions obtained, SB2 showed the capacity to inhibit H. pylori urease in a heterologous bacterial model. One additional sub-fraction (SE3) was able to simultaneously modulate the expression of two adhesins (HopZ and BabA) and one cytotoxin (CagA). The flavonol kaempferol was identified as the most interesting compound that deserves further investigation as a new hit for its capacity to modulate H. pylori virulence factors.

ObjectivesAlthough global epidemiology of Helicobacter pylori (HP) infection is well characterized, country-specific figure is more accurate for context-specific tailored interventions. The aim was to determine the prevalence, factors associated with infection, antibiotic resistance profile, and genotypes of HP in Cameroon.DesignA systematic review with meta-analysis.ParticipantsPeople living in Cameroon regardless of their clinical profile.Data sources and synthesisObservational studies published in PubMed, EMBASE, African Index Medicus, African Journals Online, and Health Sciences and Diseases up to October 12th, 2020. Study selection, data extraction, and methodological quality assessment were done by two independent authors. Random-effect meta-analysis served to pool prevalence data.ResultsFifteen studies were included. None investigated the genotypes of HP. Among symptomatic patients, the most common used test, urea breath test on gastric biopsy, yielded a prevalence 57.8% (95% confidence interval (CI): 34.3-79.5) of HP infection. This prevalence significantly varied between 47.0% (95%CI: 43.0-51.0) for antigen test in stool samples and 71.2% (95%CI: 59.1-81.9) for Giemsa on gastric biopsy; p = 0.0006. One study in asymptomatic children reported the prevalence of 52.3% (95%CI: 44.9-59.6) using antigen test for stool samples. Among the six studies investigating factors associated with HP infection, one performed a multivariable model and identified being student as protective factor compared to being employed (Odds ratio: 0.09; 95%CI: 0.02–0.49). For antibiotics used for first line treatment, HP was resistant to amoxicillin (85.6-97.1%), metronidazole (93.2-97.9%), and clarithromycin (13.6-44.7%) as reported in two studies.LimitationData were from six of the ten regions of Cameroon, hindering the generalizability of the findings to the country.ConclusionThis study depicted a high prevalence of HP infection and a worrying resistance profile to first-line antibiotics. When waiting for well-conducted studies, updated guidelines are needed for clinical practice for first-line antibiotic treatment.RegistrationPROSPERO, CRD42020220084.Strengths and limitations of this studyNot all the 10 regions of the country were represented in this study, hindering the generalizability of the findings.We were not able to substantially investigate sources of heterogeneity in the prevalence of Helicobacter pylori infection due to scarcity of data.Evidence investigating factors associated with Helicobacter pylori infection are weak and there was scarcity on data exploring antibiotic resistance profile of Helicobacter pylori.This study is the first to provide an estimate of the epidemiology and resistance profile of Helicobacter pylori in Cameroon.