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1.
Front Pharmacol ; 15: 1390500, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104390

RESUMEN

Some tannin-rich plants such as Combretum mucronatum and Phyllanthus urinaria are widely used in Africa for the control of parasitic nematodes in both humans and livestock. Tannins have been recognized as an alternative source of anthelmintic therapies, and hence, recent studies have focused on both the hydrolyzable and condensed tannins. These groups of compounds, however, have poor oral bioavailability and are metabolized by gut microbiota into lower molecular weight compounds. The role of these metabolites in the anthelmintic activities of tannins has not been explored yet. This study investigated the effects of fecal metabolism on the anthelmintic potential of procyanidin C1 (PC1) and geraniin and the tannin-enriched extracts of C. mucronatum (CML) and P. urinaria (PUH), which contain these compounds, respectively. Metabolites were formed by anaerobic fermentation of the test compounds and extracts in a fresh human fecal suspension for 0 h, 4 h, and 24 h. Lyophilized samples were tested in vitro against hookworm larvae and whipworm (Trichuris trichiura) larvae obtained from naturally infected human populations in Pru West District, Bono East Region, Ghana, and against the wildtype strain of Caenorhabditis elegans (L4). Both extracts and compounds in the undegraded state exhibited concentration-dependent inhibition of the three nematodes. Their activity, however, significantly decreased upon fecal metabolism. Without fermentation, the proanthocyanidin-rich CML extract was lethal against hookworm L3 (LC50 = 343.5 µg/mL, 95% confidence interval (CI) = 267.5-445.4), T. trichiura L1 (LC50 = 230.1 µg/mL, CI = 198.9-271.2), and C. elegans (LC50 = 1468.1 µg/mL, CI = 990.3-1946.5). PUH, from which the ellagitannin geraniin was isolated, exhibited anthelmintic effects in the unfermented form with LC50 of 300.8 µg/mL (CI = 245.1-374.8) against hookworm L3 and LC50 of 331.6 µg/mL (CI = 290.3-382.5) against T. trichiura L1, but it showed no significant activity against C. elegans L4 larvae at the tested concentrations. Similarly, both compounds, procyanidin C1 and geraniin, lost their activity when metabolized in fecal matter. The activity of geraniin at a concentration of 170 µg/mL against C. elegans significantly declined from 30.4% ± 1.8% to 14.5% ± 1.5% when metabolized for 4 h, whereas that of PC1 decreased from 32.4% ± 2.3% to 8.9% ± 0.9% with similar treatment. There was no significant difference between the anthelmintic actions of metabolites from the structurally different tannin groups. The outcome of this study revealed that the intact bulky structure of tannins (hydrolyzable or condensed) may be required for their anthelmintic action. The fermented products from the gut may not directly contribute toward the inhibition of the larvae of soil-transmitted helminths.

2.
Vet Parasitol ; 331: 110288, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39178741

RESUMEN

Parasitic infections with gastrointestinal nematodes are a serious problem for the health and welfare of domestic animals and negatively affect the economics of animal production. Haemonchus contortus is a haematophagous nematode of small ruminants responsible for significant mortality and morbidity. In addition, the widespread resistance to synthetic anthelmintic drugs emphasizes the urgent need of alternative treatment options against haemonchosis. This work aims to investigate the anthelmintic activity of an hydroethanolic Combretum mucronatum leaf extract (CMLE) against Haemonchus contortus in goats. Goats were artificially infected with 3500 third-stage larvae of H. contortus, and 21 days later, treated with CMLE (1000, 500, 250 mg/kg) for 4 consecutive days. Different parameters such as faecal egg count reduction, weight and haematocrit were monitored during the experimental period. The number of eggs per gram of faeces (EPG) was concentration-depended lower and significantly reduced compared to the untreated control (p < 0.0001). The effect of the highest CMLE dose (4 ×1000 mg/kg body weight) was similar to the effect of albendazole (1 ×5 mg/kg of body weight). The ED50 and ED90 values calculated were 189.17 and 392.33 mg/kg body weight respectively. ED50 and ED90 values were time-dependent. Moreover, CMLE improved haematocrit and weight of goats in dose-dependent and time-dependent manner. These results showed that CMLE could be used for haemonchosis treatment in small ruminants.


Asunto(s)
Antihelmínticos , Combretum , Heces , Enfermedades de las Cabras , Cabras , Hemoncosis , Haemonchus , Recuento de Huevos de Parásitos , Extractos Vegetales , Hojas de la Planta , Animales , Haemonchus/efectos de los fármacos , Hemoncosis/veterinaria , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Enfermedades de las Cabras/tratamiento farmacológico , Enfermedades de las Cabras/parasitología , Extractos Vegetales/farmacología , Antihelmínticos/farmacología , Antihelmínticos/uso terapéutico , Hojas de la Planta/química , Recuento de Huevos de Parásitos/veterinaria , Combretum/química , Heces/parasitología , Hematócrito/veterinaria , Femenino , Masculino
3.
Fitoterapia ; 177: 106120, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992475

RESUMEN

Periodontitis is clinically characterized by destruction of the tooth support system and tooth loss. Porphyromonas gingivalis (Pg) plays a dominant role in periodontitis. Fractions and isolated compounds from an acetone-water extract of the roots of Limonium brasiliense (Lb) were tested in vitro for their anti-adhesive capacity against Pg on human KB buccal cells, influence on gingipains, the main virulence factors of Pg, and biofilm formation. Fractions EAF and FLB7 (50 µg/mL) reduced the bacterial adhesion of Pg to KB cells significantly (63 resp. 70%). The proanthocyanidin samarangenin A inhibited the adhesion (72%, 30 µM), samarangenin B (71%, 20 µM), and the flavan-3-ol epigallocatechin-3-O-gallate (79%, 30 µM). Fraction AQF, representing hydrophilic compounds, reduced the proteolytic activity of Arginin-specific gingipain (IC50 12.78 µg/mL). Fractions EAF and FLB7, characterized by lipohilic constituents, inhibited Arg-gingipain (IC50 3 µg/mL). On Lysine-specific gingipain, AQF has an IC50 15.89, EAF 14.15, and FLB7 6 µg/mL. The reduced bacterial adhesion is due to a strong interaction of proanthocyanidins with gingipains. AQF, EAF, and FLB7 significantly inhibited biofilm formation: IC50 11.34 (AQF), 11.66 (EAF), and 12.09 µg/mL (FLB7). In silico analysis indicated, that the polyphenols act against specific targets of Pg, not affecting mammalian cells. Therefore, Lb might be effective for prevention of periodontal disease by influencing virulence factors of Pg.


Asunto(s)
Adhesinas Bacterianas , Adhesión Bacteriana , Biopelículas , Cisteína Endopeptidasas , Cisteína-Endopeptidasas Gingipaínas , Extractos Vegetales , Plumbaginaceae , Porphyromonas gingivalis , Factores de Virulencia , Biopelículas/efectos de los fármacos , Porphyromonas gingivalis/efectos de los fármacos , Humanos , Adhesinas Bacterianas/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Plumbaginaceae/química , Raíces de Plantas/química , Proantocianidinas/farmacología , Proantocianidinas/aislamiento & purificación , Células KB , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación
4.
Planta Med ; 90(9): 717-725, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38885660

RESUMEN

The search for new active substances against SARS-CoV-2 is still a central challenge after the COVID-19 pandemic. Antiviral agents to complement vaccination are an important pillar in the clinical situation. Selected cannabinoids such as cannabigerol, cannabicyclol, cannabichromene, and cannabicitran from Cannabis sativa and synthetic homologues of cannabigerol and cannabicyclol were evaluated for effects on the cell viability of Vero cells (CC50 of cannabigerol and cannabicyclol 40 resp. 38 µM) and reduced virus entry of vesicular stomatitis pseudotyped viruses with surface-expressed SARS-CoV-2 spike protein at 20 µM. In addition to a reduction of pseudotyped virus entry, a titer reduction assay on Vero cells after preincubation of Wuhan SARS-CoV-2 significantly confirmed antiviral activity. Investigations on the molecular targets addressed by cannabigerol and cannabicyclol indicated that both compounds are inhibitors of SARS-CoV-2 spike protein-mediated membrane fusion, as could be shown by a virus-free reporter fusion inhibition assay (EC50 for cannabigerol 5.5 µM and for cannabicyclol 10.8 µM) and by monitoring syncytia formation in Vero reporter cells. Selectivity indices were calculated as 7.4 for cannabigerol and 3.5 for cannabicyclol. Systematic semisynthetic alterations of cannabigerol and cannabicyclol indicated that the side chains of both compounds do not contribute to the observed anti-membrane fusion activity.


Asunto(s)
Antivirales , Cannabinoides , SARS-CoV-2 , Internalización del Virus , Chlorocebus aethiops , Células Vero , Animales , SARS-CoV-2/efectos de los fármacos , Cannabinoides/farmacología , Antivirales/farmacología , Internalización del Virus/efectos de los fármacos , Glicoproteína de la Espiga del Coronavirus/metabolismo , Humanos , Supervivencia Celular/efectos de los fármacos , Tratamiento Farmacológico de COVID-19 , Cannabis/química
5.
Arch Toxicol ; 98(7): 2019-2045, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38704806

RESUMEN

For endocrine disrupting chemicals (EDC) the existence of "safe exposure levels", that is exposure levels that do not present an appreciable risk to human health is most controversially discussed, as is the existence of health-based reference values. Concerns have been especially raised that EDCs might not possess a threshold level such that no exposure level to EDCs can be considered safe. To explore whether or not threshold levels can be identified, we performed a screening exercise on 14 pesticidal and biocidal active substances previously identified as EDCs in the European Union. The respective substances are ideal subjects for case studies to review for endocrine activity and disruptive potential following well-defined regulatory assessment based on solid data to effectually establish adversity as consequence of endocrine disruption. Dimethomorph, metiram and propiconazole for which the weight of evidence demonstrating endocrine disruption was the strongest were used as subjects for further study. Epoxiconazole was additionally selected as its effects on the endocrine system are extensive. For all four substances, analysis of the toxicological data clearly indicated thresholds of adversity below which no adverse effects mediated through an endocrine mechanism were observed. Particular emphasis was placed on mechanistic considerations including homeostasis and the concept of adversity. As a proof of concept this study provides evidence that like other substances of toxicological concern EDCs have threshold levels for adversity. While for some EDCs the respective thresholds might indeed be very low this shows that, data allowing, for other EDCs sufficiently protective reference values can be derived.


Asunto(s)
Disruptores Endocrinos , Disruptores Endocrinos/toxicidad , Humanos , Medición de Riesgo , Animales , Plaguicidas/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Triazoles/toxicidad , Unión Europea , Nivel sin Efectos Adversos Observados , Sistema Endocrino/efectos de los fármacos , Compuestos Epoxi/toxicidad
6.
Planta Med ; 90(6): 416-425, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38527490

RESUMEN

"Children are not small adults with respect to the treatment with medicinal products." This statement of the WHO was the basis for the initiative of the European Commission for the establishment of a paediatric regulation in 2007 to improve the health of children by facilitating the development of medicines for children and adolescents. Seventeen years later, in the field of herbal medicinal products, results are still sobering. Therefore, the Foundation Plants for Health, Society for Medicinal Plants and Natural Products Research, and German Society for Phytotherapy organised a symposium to assess the status quo for the paediatric use of herbal medicinal products (HMPs), to analyse the causes of the current situation, and to discuss strategies for establishing the proof of safe and efficacious HMPs for children.The current situation for HMPs and their use in children is not fulfilling the requirements of legislation. HMPs in paediatrics are effective and safe, but considering the needs of children is necessary. In European countries, the use, registration, and marketing of HMPs are different, depending on the respective national regulations and specific traditions. EU herbal monographs are the best common denominator for such procedures. Emerging safety discussions must be considered. New approaches with real-world data might be a solution. The regulatory framework is to be adapted. Defining rationalised dosing for HMPs can be achieved by the extrapolation of data from adults, by using existing clinical data for children, and by using RWD. Therefore, a strong need for revising restrictions for the use of HMPs in children and rationalising defined dosage regimes is obvious.


Asunto(s)
Fitoterapia , Humanos , Niño , Plantas Medicinales/química , Adolescente , Preparaciones de Plantas/administración & dosificación , Preparaciones de Plantas/uso terapéutico
7.
Parasit Vectors ; 17(1): 99, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429804

RESUMEN

BACKGROUND: Soil-transmitted helminths (STH) infect more than a quarter of the world's human population. In the absence of vaccines for most animal and human gastrointestinal nematodes (GIN), treatment of infections primarily relies on anthelmintic drugs, while resistance is a growing threat. Therefore, there is a need to find alternatives to current anthelmintic drugs, especially those with novel modes of action. The present work aimed to study the composition and anthelmintic activity of Combretum mucronatum leaf extract (CMLE) by phytochemical analysis and larval migration inhibition assays, respectively. METHODS: Combretum mucronatum leaves were defatted with petroleum ether and the residue was extracted by ethanol/water (1/1) followed by freeze-drying. The proanthocyanidins and flavonoids were characterized by thin layer chromatography (TLC) and ultra-high performance liquid chromatography (UPLC). To evaluate the inhibitory activity of this extract, larval migration assays with STH and GIN were performed. For this purpose, infective larvae of the helminths were, if necessary, exsheathed (Ancylostoma caninum, GIN) and incubated with different concentrations of CMLE. RESULTS: CMLE was found to be rich in flavonoids and proanthocyanidins; catechin and epicatechin were therefore quantified for standardization of the extract. Data indicate that CMLE had a significant effect on larval migration. The effect was dose-dependent and higher concentrations (1000 µg/mL) exerted significantly higher larvicidal effect (P < 0.001) compared with the negative control (1% dimethyl sulfoxide, DMSO) and lower concentrations (≤ 100 µg/ml). Infective larvae of Ascaris suum [half-maximal inhibitory concentration (IC50) = 5.5 µg/mL], Trichuris suis (IC50 = 7.4 µg/mL), and A. caninum (IC50 = 18.9 µg/mL) were more sensitive to CMLE than that of Toxocara canis (IC50 = 310.0 µg/mL), while infective larvae of Toxocara cati were largely unaffected (IC50 > 1000 µg/mL). Likewise, CMLE was active against most infective larvae of soil-transmitted ruminant GIN, except for Cooperia punctata. Trichostrongylus colubriformis was most sensitive to CMLE (IC50 = 2.1 µg/mL) followed by Cooperia oncophora (IC50 = 27.6 µg/mL), Ostertagia ostertagi (IC50 = 48.5 µg/mL), Trichostrongylus axei (IC50 = 54.7 µg/mL), Haemonchus contortus (IC50 = 145.6 µg/mL), and Cooperia curticei (IC50 = 156.6 µg/mL). CONCLUSIONS: These results indicate that CMLE exhibits promising anthelmintic properties against infective larvae of a large variety of soil-transmitted nematodes.


Asunto(s)
Antihelmínticos , Combretum , Helmintos , Nematodos , Proantocianidinas , Trichostrongyloidea , Animales , Humanos , Combretum/química , Proantocianidinas/farmacología , Proantocianidinas/química , Larva , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antihelmínticos/farmacología , Rumiantes , Flavonoides/farmacología , Fitoquímicos/farmacología
8.
Appl Microbiol Biotechnol ; 108(1): 171, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38265503

RESUMEN

Infections caused by Campylobacter spp. are a major cause of severe enteritis worldwide. Multifactorial prevention strategies are necessary to reduce the prevalence of Campylobacter. In particular, antiadhesive strategies with specific inhibitors of early host-pathogen interaction are promising approaches to reduce the bacterial load. An in vitro flow cytometric adhesion assay was established to study the influence of carbohydrates on the adhesion of C. jejuni to Caco-2 cells. Chitosans with a high degree of polymerization and low degree of acetylation were identified as potent antiadhesive compounds, exerting significant reduction of C. jejuni adhesion to Caco-2 cells at non-toxic concentrations. Antiadhesive and also anti-invasive effects were verified by confocal laser scanning microscopy. For target identification, C. jejuni adhesins FlpA and JlpA were expressed in Escherichia coli ArcticExpress, and the influence of chitosan on binding to fibronectin and HSP90α, respectively, was investigated. While no effects on FlpA binding were found, a strong inhibition of JlpA-HSP90α binding was observed. To simulate real-life conditions, chicken meat was inoculated with C. jejuni, treated with antiadhesive chitosan, and the bacterial load was quantified. A strong reduction of C. jejuni load was observed. Atomic force microscopy revealed morphological changes of C. jejuni after 2 h of chitosan treatment, indicating disturbance of the cell wall and sacculi formation by electrostatic interaction of positively charged chitosan with the negatively charged cell surface. In conclusion, our data indicate promising antiadhesive and anti-invasive potential of high molecular weight, strongly de-acetylated chitosans for reducing C. jejuni load in livestock and food production. KEY POINTS: • Antiadhesive effects of chitosan with high DP/low DA against C. jejuni to host cells • Specific targeting of JlpA/Hsp90α interaction by chitosan • Meat treatment with chitosan reduces C. jejuni load.


Asunto(s)
Campylobacter jejuni , Quitosano , Humanos , Células CACO-2 , Acetilación , Adhesinas Bacterianas , Escherichia coli
10.
Sci Rep ; 13(1): 17815, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857738

RESUMEN

Tamm-Horsfall protein (THP) is a highly N-glycosylated protein from epithelial cells of the ascending limb of Henle loop. It is secreted into the urine as part of the innate immune response against uropathogenic pathogens. As women are more likely to suffer from urinary tract infections, biomedical studies were conducted to investigate sex-differences in THP excretion, as well as differences in the THP N-glycosylation pattern. A total of 238 volunteers (92 men, 146 women, 69 with hormonal contraceptives) participated in this study, providing urine samples. Women showed a clear tendency to have higher THP concentration and excretion rates than men (p < 0.16). Regular intake of hormonal contraceptives had no significant influence on urinary THP concentration compared to no regular intake. The individual N-glycosylation pattern of THP in urine samples from randomly selected individuals (10 female, 10 male) was investigated after enzymatic release and MS analysis of the oligosaccharides. Female subjects tended to have an increased proportion of oligomannose type N-glycans and non-fucosylated glycans, whereas men had an increased proportion of fucosylated complex-type glycans. The higher level of oligomannose-type glycans in THP from women might be explained by a self-defence mechanism to overcome the higher infections pressure by the female anatomical properties.


Asunto(s)
Asa de la Nefrona , Polisacáridos , Humanos , Masculino , Femenino , Uromodulina/metabolismo , Glicosilación , Asa de la Nefrona/metabolismo , Polisacáridos/metabolismo , Anticonceptivos
11.
PLoS One ; 18(10): e0289334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37874837

RESUMEN

New antibiotics are urgently needed due to the huge increase of multidrug-resistant bacteria. The underexplored gram-negative bacterium Enterobacter cloacae is known to cause severe urinary tract and lung infections (UTIs). The pathogenicity of E. cloacae in UTI has only been studied at the bioinformatic level, but until now not within systematic in vitro investigations. The present study assesses different human cell lines for monitoring the early steps of host-pathogen interaction regarding bacterial adhesion to and invasion into different host cells by flow cytometric adhesion assay, classical cell counting assay, gentamicin invasion assay, and confocal laser scanning microscopy. To our knowledge, this is the first report in which E. cloacae has been investigated for its interaction with human bladder, kidney, skin, and lung cell lines under in vitro conditions. Data indicate that E. cloacae exerts strong adhesion to urinary tract (bladder and kidney) and lung cells, a finding which correlates with the clinical relevance of the bacterium for induction of urinary tract and lung infections. Furthermore, E. cloacae ATCC 13047 barely adheres to skin cells (A-431) and shows no relevant interaction with intestinal cells (Caco-2, HT-29), even in the presence of mucin (HT29 MTX). In contrast, invasion assays and confocal laser scanning microscopy demonstrate that E. cloacae internalizes in all tested host cells, but to a different extent. Especially, bladder and kidney cells are being invaded to the highest extent. Defective mutants of fimH and fimA abolished the adhesion of E. cloacae to T24 cells, while csgA deletion had no influence on adhesion. These results indicate that E. cloacae has different pattern for adhesion and invasion depending on the target tissue, which again correlates with the clinical relevance of the pathogen. For detailed investigation of the early host-pathogen interaction T24 bladder cells comprise a suitable assay system for evaluation the bacterial adhesion and invasion.


Asunto(s)
Enterobacter cloacae , Infecciones Urinarias , Humanos , Células CACO-2 , Antibacterianos/farmacología , Células Epiteliales
12.
Planta Med ; 89(11): 1024-1025, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37657481
13.
Phytochemistry ; 215: 113854, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37716546

RESUMEN

Many people in developing countries rely on herbal remedies for their primary healthcare needs. The challenge however is that several of these products lack proper documentation of quality and safety. To ensure consistent quality, validated methods are needed to establish and control quality attributes associated with identity, purity, and levels of bioactive constituents of the respective herbal materials. The present study focused on Phyllanthus urinaria (PU), a widely used medicinal plant in Ghana and West Africa that lacks the necessary quality control standards. The study aimed to develop an HPTLC identification method, which together with UPLC-ESI-Q-TOF-MS/MS analysis established the identity of PU samples and differentiated PU from other closely related Phyllanthus species. Quantitative UPLC and HPTLC methods were developed to assess the contents of selected active markers in the PU samples, which invariably led to the proposal of acceptance criteria for the active markers. Prior to the content analyses, the sample extraction procedure was optimized through the use of Design of Experiment method. The effects of harvest time and geographic origin on the content of active compounds were demonstrated in the investigations. PU samples were also found to be contaminated with higher levels of pesticides like chlorpyrifos and folpet. Essentially, this study provides analytical protocols, insights into the quality status of PU samples in Ghana, and analytical specifications contained in a drafted monograph for future consideration in regional and subregional African pharmacopoeias.


Asunto(s)
Phyllanthus , Plantas Medicinales , Humanos , Plantas Medicinales/química , Phyllanthus/química , Espectrometría de Masas en Tándem , África Occidental , Extractos Vegetales/farmacología
14.
Planta Med ; 89(13): 1215-1228, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37459860

RESUMEN

The aerial parts of Phyllanthus urinaria are used in traditional medicine in West Africa against helminthiasis, but their anthelmintic potential has not been evaluated until now. Within the current study, a hydroacetonic extract (AWE) and fractions and isolated ellagitannins from P. urinaria were, therefore, tested in vitro against Caenorhabditis elegans and the larvae of the animal parasites Toxocara canis, Ascaris suum, Ancylostoma caninum, and Trichuris suis. Compounds 1:  - 13: , mainly representing ellagitannins, were isolated using different chromatographic methods, and their structures were elucidated by HR-MS and 1H/13C-NMR. AWE exerted concentration-dependent lethal effects (LC50 of 2.6 mg/mL) against C. elegans and inhibited larval migration of all animal parasites tested (T. suis L1 IC50 24.3 µg/mL, A. suum L3 IC50 35.7 µg/mL, A. caninum L3 IC50 112.8 µg/mL, T. canis L3 IC50 1513.2 µg/mL). The anthelmintic activity of AWE was mainly related to the polar, tannin-containing fractions. Geraniin 1: , the major ellagitannin in the extract, showed the strongest anthelmintic activity in general (IC50 between 0.6 and 804 µM, depending on parasite species) and was the only compound active against A. caninum (IC50 of 35.0 µM). Furosin 9: was least active despite structural similarities to 1: . Among the parasites tested, Trichuris suis L1 larvae turned out to be most sensitive with IC50 of 0.6, 6.4, 4.0, 4.8, and 2.6 µM for geraniin 1: , repandusinic acid A 3: , punicafolin 8: , furosin 9: , and phyllanthusiin A 10: , respectively.

16.
Appl Microbiol Biotechnol ; 107(9): 2725-2754, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36941439

RESUMEN

Campylobacter jejuni, causing strong enteritis, is an unusual bacterium with numerous peculiarities. Chemotactically controlled motility in viscous milieu allows targeted navigation to intestinal mucus and colonization. By phase variation, quorum sensing, extensive O-and N-glycosylation and use of the flagellum as type-3-secretion system C. jejuni adapts effectively to environmental conditions. C. jejuni utilizes proteases to open cell-cell junctions and subsequently transmigrates paracellularly. Fibronectin at the basolateral side of polarized epithelial cells serves as binding site for adhesins CadF and FlpA, leading to intracellular signaling, which again triggers membrane ruffling and reduced host cell migration by focal adhesion. Cell contacts of C. jejuni results in its secretion of invasion antigens, which induce membrane ruffling by paxillin-independent pathway. In addition to fibronectin-binding proteins, other adhesins with other target structures and lectins and their corresponding sugar structures are involved in host-pathogen interaction. Invasion into the intestinal epithelial cell depends on host cell structures. Fibronectin, clathrin, and dynein influence cytoskeletal restructuring, endocytosis, and vesicular transport, through different mechanisms. C. jejuni can persist over a 72-h period in the cell. Campylobacter-containing vacuoles, avoid fusion with lysosomes and enter the perinuclear space via dynein, inducing signaling pathways. Secretion of cytolethal distending toxin directs the cell into programmed cell death, including the pyroptotic release of proinflammatory substances from the destroyed cell compartments. The immune system reacts with an inflammatory cascade by participation of numerous immune cells. The development of autoantibodies, directed not only against lipooligosaccharides, but also against endogenous gangliosides, triggers autoimmune diseases. Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni. Together with the response of the immune system, this limits infection time. Based on the structural interactions between host cell and bacterium, the numerous virulence mechanisms, signaling, and effects that characterize the infection process of C. jejuni, a wide variety of targets for attenuation of the pathogen can be characterized. The review summarizes strategies of C. jejuni for host-pathogen interaction and should stimulate innovative research towards improved definition of targets for future drug development. KEY POINTS: • Bacterial adhesion of Campylobacter to host cells and invasion into host cells are strictly coordinated processes, which can serve as targets to prevent infection. • Reaction and signalling of host cell depend on the cell type. • Campylobacter virulence factors can be used as targets for development of antivirulence drug compounds.


Asunto(s)
Infecciones por Campylobacter , Campylobacter jejuni , Humanos , Proteínas Bacterianas/metabolismo , Campylobacter jejuni/metabolismo , Fibronectinas/metabolismo , Dineínas/metabolismo , Factores de Virulencia/metabolismo , Adhesinas Bacterianas/metabolismo , Células Epiteliales/microbiología , Adhesión Bacteriana
17.
Planta Med ; 89(8): 778-789, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34521130

RESUMEN

Orthosiphon stamineus leaves (Java tea) extract is traditionally used for the treatment of urinary tract infections. According to recent in vitro data, animal infection studies, and transcriptomic investigations, polymethoxylated flavones from Java tea exert antiadhesive activity against uropathogenic Escherichia coli (UPEC). This antiadhesive activity has been shown to reduce bladder and kidney lesion in a mice infection model. As no data on the antivirulent activity of Java tea intake on humans are available, a biomedical study was performed on 20 healthy volunteers who self-administered Orthosiphon infusion (4 × 3 g per day, orally) for 7 days. The herbal material used for the study conformed to the specification of the European Pharmacopoeia, and ultra high-performance liquid chromatography (UHPLC) of the infusion showed rosmarinic acid, caffeic acid, and cichoric acid to be the main compounds aside from polymethoxylated flavones. Rosmarinic acid was quantified in the tea preparations with 243 ± 22 µg/mL, indicating sufficient reproducibility of the preparation of the infusion. Urine samples were obtained during the biomedical study on day 1 (control urine, prior to Java tea intake), 3, 6 and 8. Antiadhesive activity of the urine samples was quantified by flowcytometric assay using pre-treated UPEC NU14 and human T24 bladder cells. Pooled urine samples indicated significant inhibition of bacterial adhesion on day 3, 6 and 8. The urine samples had no influence on the invasion of UPEC into host cells. Bacterial proliferation was slightly reduced after 24 h incubation with the urine samples. Gene expression analysis (qPCR) revealed strong induction of fitness and motility gene fliC and downregulation of hemin uptake system chuT. These data correlate with previously reported datasets from in vitro transcriptomic analysis. Increased bacterial motility was monitored using a motility assay in soft agar with UPEC UTI89. The intake of Java tea had no effect on the concentration of Tamm-Horsfall Protein in the urine samples. The present study explains the antiadhesive and anti-infective effect of the plant extract by triggering UPEC from a sessile lifestyle into a motile bacterial form, with reduced adhesive capacity.


Asunto(s)
Flavonas , Orthosiphon , Escherichia coli Uropatógena , Animales , Ratones , Humanos , Orthosiphon/química , Reproducibilidad de los Resultados , Antibacterianos/farmacología , Hojas de la Planta/química , Flavonas/farmacología , Modelos Animales de Enfermedad , Ácido Rosmarínico
18.
Planta Med ; 89(11): 1052-1062, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34953469

RESUMEN

Rumex acetosa significantly inhibits the adhesion of Porphyromonas gingivalis (P. g.) to eukaryotic host cells in vitro. The objective of this randomized placebo-controlled pilot-trial was to analyze effects of a mouth rinse containing 0.8% (w/w) of a quantified proanthocyanidin-enriched extract from Rumex acetosa (RA1) on microbiological, clinical, and cytological parameters in systemically healthy individuals without history of periodontitis, harboring P. g. intraorally. 35 subjects received a supragingival debridement (SD) followed by mouth rinsing (3 times daily) with either RA1 mouth rinse solution (test) or placebo (control) for 7 days as adjunct to routine oral hygiene. Supragingival biofilm samples were taken at screening visit, baseline (BL), 2, 4, 7 and 14 days after SD. P. g. and 11 other oral microorganisms were detected and quantified by rtPCR. Changes in the oral microbiota composition of one test and one control subject were assessed via high throughput 16S rRNS gene amplicon sequencing. Approximal Plaque Index (API) and the modified Sulcular Bleeding Index (SBI) were assessed at BL, 7- and 14-days following SD. Brush biopsies were taken at BL and 14 d following SD. Intergroup comparisons revealed no significant microbiological, cytological, and clinical differences at any timepoint. However, a significant reduction in SBI at day 14 (p = 0.003) and API at day 7 (p = 0.02) and day 14 (p = 0.009) was found in the test group by intragroup comparison. No severe adverse events were observed. The results indicate that RA1 mouth rinse is safe but does not seem to inhibit colonization of P. g. or improve periodontal health following SD.


Asunto(s)
Antisépticos Bucales , Proantocianidinas , Rumex , Antisépticos Bucales/farmacología , Antisépticos Bucales/uso terapéutico , Proyectos Piloto , Porphyromonas gingivalis , Proantocianidinas/farmacología
19.
Planta Med ; 89(11): 1074-1086, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35598603

RESUMEN

Periodontal diseases are a global oral health problem affecting almost 10% of the global population. Porphyromonas gingivalis is one of the main bacteria involved in the initiation and progression of inflammatory processes as a result of the action of the cysteine proteases lysin- and arginine-gingipain. Surelease/polycarbophil microparticles containing a lyophilized proanthocyanidin-enriched fraction from the rhizomes of Limonium brasiliense, traditionally named "baicuru" (ethyl acetate fraction), were manufactured. The ethyl acetate fraction was characterized by UHPLC by the presence of samarangenins A and B (12.10 ± 0.07 and 21.05 ± 0.44%, respectively) and epigallocatechin-3-O-gallate (13.44 ± 0.27%). Physiochemical aspects of Surelease/polycarbophil microparticles were characterized concerning particle size, zeta potential, entrapment efficiency, ethyl acetate fraction release, and mucoadhesion. Additionally, the presence of the ethyl acetate fraction-loaded microparticles was performed concerning potential influence on viability of human buccal KB cells, P. gingivalis adhesion to KB cells, gingipain activity, and P. gingivalis biofilm formation. In general, all Surelease/polycarbophil microparticles tested showed strong adhesion to porcine cheek mucosa (93.1 ± 4.2% in a 30-min test), associated with a prolonged release of the ethyl acetate fraction (up to 16.5 ± 0.8% in 24 h). Preincubation of KB cells with Surelease/polycarbophil microparticles (25 µg/mL) resulted in an up to 93 ± 2% reduced infection rate by P. gingivalis. Decreased activity of the P. gingivalis-specific virulence factors lysin- and arginine-gingipain proteases by Surelease/polycarbophil microparticles was confirmed. Surelease/polycarbophil microparticles decreased biofilm formation of P. gingivalis (97 ± 2% at 60 µg/mL). Results from this study prove the promising activity of Surelease/polycarbophil microparticles containing ethyl acetate fraction microparticles as a prophylaxis strategy to prevent the recurrence of P. gingivalis.


Asunto(s)
Plumbaginaceae , Proantocianidinas , Humanos , Animales , Porcinos , Cisteína-Endopeptidasas Gingipaínas , Porphyromonas gingivalis , Adhesinas Bacterianas , Proantocianidinas/farmacología , Cisteína Endopeptidasas , Plumbaginaceae/química
20.
Planta Med ; 89(9): 860-878, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36539209

RESUMEN

Herbal medicines are invaluable in African medicine, but quality and safety are not documented in many cases. Besides controlled farming, validated quality control methods are needed to ensure identity, purity, and content. Analytical specifications within modern monographs are needed for consistent batch quality. Combretum mucronatum leaves are widely used in West Africa, but state-of-the-art quality control methods and specifications are non-existent. The aim of the following study was the development of ICH-validated chromatographic protocols for identity, purity, content assay, and analytical specifications for consideration into pharmacopoeial monographs. UPLC-ESI-Q-TOF-MS/MS was used for untargeted phytochemical information on composition. Optimisation of extraction was based on phytochemical profiling. HPTLC was used for differentiation of C. mucronatum from other Combretum species and UPLC for simultaneous determination of 7 marker compounds. C. mucronatum batch analyses (n = 49) investigated the influence of harvest time and geographical origin. Pesticides screening from a 349-compound panel were carried out. 30 compounds, identified by LC-MS, were used for characterization of the plant material. Orietin, isoorientin, vitexin and isovitexin were used as specific marker compounds for qualitative and quantitative HPTLC purposes, while UPLC quantified additionally epicatechin, procyanidins B2 and C1. Influence of harvest time and geographic origin on the content of marker compounds was observed. Differences in the metabolite profiles of C. mucronatum compared to related Combretum species were established for quality control purposes. Contamination with high amoounts of chlorpyrifos, and folpet (sum of folpet and phtalimide, expressed as folpet) were also observed.The study provides analytical protocols, analytical specifications and a drafted monograph for consideration for African pharmacopoeias, and reveals potential challenges in the quality of C. mucronatum.


Asunto(s)
Combretum , Combretum/química , Espectrometría de Masas en Tándem , Flujo de Trabajo , Extractos Vegetales
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