Propolis polyphenolic compounds affect the viability and structure of Helicobacter pylori in vitro

ABSTRACT To evaluate the anti-Helicobacter pylori activity of the major polyphenol compounds of propolis and their cellular damage, both as single molecule or in combination. Honey bees propolis were fractionated by using CPC and preparative HPLC. Four major polyphenols (chrysin, pinocembrin, galangin and caffeic acid phenethyl ester) were identified by thin layer chromatography-mass spectroscopy and liquid chromatography-mass spectroscopy. These compounds inhibited both ATCC and clinical H. pylori strains, with caffeic acid phenethyl ester being the most active. The four compounds presented minimum inhibitory concentration in the range 256-1024 µg ml−1 and a fractional inhibitory concentration of 64-512 µg ml−1. In mixtures all compounds showed an indifference effect (FIC < 0.15) but chrysin + galangin which was synergistic (FIC = 2.0). Killing curves show a similar behavior as the antibiotic amoxycillin. On the other hand, analyses by transmission electron microscopy at sub inhibitory concentration show vesicle formation and cell lysis after exposition to both individual polyphenol compounds and in mixture. The major compounds of propolis show anti-H. pylori activity both as individual compounds and in mixture. When combined they present mainly indifference but exert a lytic activity upon H. pylori, suggesting a potential bactericidal activity of propolis.

Detection of intracellular Helicobacter pylori in Candida. SPP from neonate oral swabs

SUMMARY BACKGROUND: There is evidence of detection of Helicobacter pylori (H. pylori) in the stool of newborns and in the yeast that colonizes the oral cavity of this age group. However, there is a lack of research to confirm it. This study proposes to determine the existence of the bacteria at an early age, specifically in newborns. OBJECTIVE: To identify intracellular H. pylori in oral yeasts and to detect antigens of the bacteria in newborn stools. METHODOLOGY: Cross-sectional and descriptive study. Samples were obtained from infants (oral swab and meconium). Identification of yeast species was performed using the following techniques: CHROMagar Candida, Germinal Tube Test and API Candida Identification System, then the yeasts were observed by light microscopy and fluorescence. Detection of H. pylori antigen in meconium and PCR were performed to amplify specific genes of the bacterium (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 and dupA). RESULTS: Intracellular H. pylori was detected in yeast of the species Candida glabrata (C. glabrata) isolated from an oral swab of a newborn. CONCLUSION: The results of this study evidenced the existence of intracellular H. pylori in newborns.

RESUMO ANTECEDENTES: Há evidências de detecçâo de Helicobacter pylori (H. pylori) em fezes de recém-nascidos, como também dentro de leveduras que colonizam a cavidade oral dessa faixa etária. No entanto, faltam investigações que confirmem esses achados. OBJETIVO: Identificar H. pylori intracelular em leveduras de origem oral e detectar antígenos dessa bactéria em fezes neonatais. METODOLOGIA: Estudo transversal e descritivo. As amostras foram obtidas de bebês (zaragatoa oral e mecônio). As identificações das espécies de leveduras foram realizadas utilizando as seguintes técnicas: CHROMagar Candida, teste de tubo germinativo e sistema de identificação API Cândida. As leveduras foram observadas por microscopía óptica e fluorescência. Realizou-se a detecçâo de antígeno de H. pylori em mecônio e PCR para a amplificação de genes específicos desta bactéria (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 e dupA). RESULTADOS: Foi detectado H. pylori intracelular em leveduras da espécie Candida glabrata (C. glabrata) isoladas a partir de zaragatoas oral de um recém-nascido. CONCLUSÃO: Os resultados deste estudo evidenciaram a existência interna de levedura de H. pylori em recém-nascidos.

Characterization of Lactobacillus fermentum UCO-979C, a probiotic strain with a potent anti-Helicobacter pylori activity

Background: Helicobacter pylori is considered as the main risk factor in the development of gastric cancer. In the present study, we performed a detailed characterization of the probiotic properties and the anti-H. pylori activity of a previously isolated lactobacillus strain ­ Lactobacillus fermentum UCO-979C ­ obtained from human gut. Results: The strain tolerated pH 3.0; grew in the presence of 2% bile salts; produced lactic acid and hydrogen peroxide; aggregated in saline solution; showed high hydrophobicity; showed high adherence to glass; Caco-2 and gastric adenocarcinoma human cells (AGS) cells; showed an efficient colonization in Mongolian Gerbils; and potently inhibited the growth and urease activity of H. pylori strains. L. fermentum UCO-979C significantly inhibited H. pylori-induced IL-8 production in AGS cells and reduced the viability of H. pylori. With regard to innocuousness, the strain UCO-979C was susceptible to several antibiotics and did not produce histamine or beta-haemolysis in blood agar containing red blood cells from various origins. Conclusion: The results demonstrated that L. fermentum UCO-979C is a very good candidate as a probiotic for the protection of humans against H. pylori infections.

Effect of pH in the survival of Lactobacillus salivarius strain UCO_979C wild type and the pH acid acclimated variant

Background Bacterial acclimation involves cellular changes permitting the survival of a microorganism to prolonged acid pH exposure. The general aim of this work is to support this idea by determining the effect of pH in the survival of the human gastric derived probiotic strain Lactobacillus salivarius UCO_979C-1 (wild type) and L. salivarius UCO_979C-2 (acclimation to pH 2.6), which possesses anti-Helicobacter pylori properties. Results To assess this aim, the exopolysaccharide production through the phenol-sulfuric acid method was evaluated. Moreover, morphological and structural changes by transmission and scanning electron microscopy were observed. The bacterial survival was measured by viable count. The results showed that the acclimated variant strain synthesized higher levels of exopolysaccharide (690 ± 0.03 mg/L) more than the wild type (450 ± 0.12 mg/L). In addition, the acclimated variant preserved the viable count at pH 2.6 for 48 h, whereas the wild type strain decreases after 6 h and was non-viable at 24 h. Conclusion The results suggest that the acid stress acclimation of the strain L. salivarius UCO_979C-1 modified some cellular properties making this strain potentially useful as a gastric probiotic.

Comparación de Helicobacter pylori en cavidad oral y mucosa gástrica de acuerdo a genotipo de virulencia (cagA y vacAm 1) / Comparison of Helicobacter pylori in oral cavity and gastric mucosa according to virulence genotype (cagA and vacA m 1)

Objective: To compare the virulence genotype (cagA and vacA ml genes) of Helicobacter pylori obtained simultaneously from gastric mucosa and oral cavity. Material and Methods: Gastric samples of 18 patients were obtained by endoscopic biopsies. Oral samples of these patients were obtained from dental plaque and saliva swabs from the floor of the mouth and the base of the tongue. All samples were studied by conventional PCR and real-time PCR (RT-PCR). Virulence genes cagA and vacA ml were studied by RT- PCR. Results: According to presence and/or absence of cagA and vacAm1 genes, seven different combinations were observed. Conclusion: These results suggest that there is a variety of genetic profiles of Helicobacter pylori in the stomach and oral cavity, with a predominance of less virulent genotypes in the patients included in this study (cagA-, vacA m1-).

Objetivo: Comparar el genotipo de virulencia (genes cagA y vacA m1) de Helicobacter pylori, obtenido simultáneamente de mucosa gástrica y cavidad oral. Material y Métodos: Para esto se incluyeron muestras de biopsias gástricas de 18 pacientes. Las muestras orales de estos pacientes fueron obtenidas de placa bacteriana y saliva del piso de boca y base de la lengua. Las muestras fueron estudiadas con RPC convencional y RPC en tiempo real (RPC-TR). Los genes de virulencia cagA y vacA m1 fueron estudiados con RPC-TR. Resultados: De acuerdo a la presencia o ausencia de los genes de virulencia cagA y vacA m1 detectados en las muestras gástricas y orales, se pudieron diferenciar siete combinaciones diferentes. Conclusión: Estos resultados sugieren que existe una variedad de genotipos de virulencia en Helicobacter pylori en el estómago y la cavidad oral, predominando en los pacientes incluidos en este estudio las cepas con genotipos asociados a menor virulencia (cagA-, vacA m1-).

Los polifenoles antioxidantes extraídos del epicarpio de Palta (Persea americana var. Hass) inhiben la ureasa de Helicobacter pylori / Antioxidant polyphenols extracted from Avocado epicarp (Persea americana var. Hass) inhibit Helicobacter pylori urease

Chronic infection by Helicobacter pylori produce chronic gastritis leading to other more severe pathologies as peptic ulcer and gastric adenocarcinoma. New anti-H. pylori agents has been found in natural products, particularly polyphenols. The inhibition of enzymes such us urease appears to be an interesting strategy by which polyphenols could limit the colonization by H. pylori. From the exocarp of Persea americana (avocado fruit), we obtain a procyanidin-rich extract with a 77 percent of gallic acid equivalents (GAE). Such procyanidins derived from epicatechin. with a mean degree of polymerization DPm = 6.10. The antioxidant capacity was assessed by different methods as TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocin. The extract shown inhibitory activity against H. pylori urease with an IC50 = 1.02 ug GAE/mL. In order to obtain clusters of procyanidins with different molecular weights, avocado peel extract was fractioned. A clear relation between the molecular size of procyanidins and their urease inhibitory activity was observed.

La infección crónica por Helicobacter pylori produce gastritis crónica o patologías más severas como la úlcera péptica y adenocarcinoma gástrico. Nuevos agentes anti-H. pylori se han encontrado en los productos naturales, donde destacan los polifenoles. La inhibición de enzimas como la ureasa, resulta ser una estrategia interesante mediante la cual los polifenoles pueden limitar la colonización por H. pylori. A partir del epicarpio del fruto de Persea americana (palto) se obtuvo un extracto polifenólico (77 por ciento de EAG), rico en procianidinas derivadas de epicatequina, con un grado de polimerización DPm = 6.10. La capacidad antioxidante fue evaluada mediante TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocina. El extracto mostró una actividad inhibitoria de la ureasa de H. pylori con un IC50 = 1.02 ug EAG/mL. El fraccionamiento de las procianidinas permitió agruparlas según su peso molecular, observándose una clara relación entre su tamaño y la capacidad de inhibir la ureasa.