Development of a cell-based reporter assay for detection of Human alphaherpesviruses.

Immunosuppressed patients can suffer from Human alphaherpesvirus (HSV) infection with fast evolution, severe atypical symptomatology, and often-fatal outcome. Thus, the development and validation of new methods in vitro and in vivo to promote an early diagnosis and effective treatment of these patients are crucial. Therefore, this work aimed to develop a cell-based reporter assay for the detection of HSV through the transfection of Vero cells with the ICP10 promoter from HSV-2 linked to the pZsGreen1-1 plasmid. The assay was evaluated on Vero cells infected with HSV-1 or HSV-2 and followed by treating them with anti-HSV agents (acyclovir, gallic acid, convallatoxin, and Uncaria sp. extract) or with no anti-HSV activity agents (Passiflora edulis extract and cardenolide derivatives). The GFP expression was increased by both HSV cellular infection, which was detected by flow cytometry and fluorescence microscopy. F2R Zsgreen1-1 cells infection with 200 and 600 PFU/mL of HSV-2 increased the fluorescence intensity, when compared to the controls, by approximately 30% and 60%, respectively. Infection with 100 and 600 PFU/mL of HSV-1 also increased the fluorescence intensity by approximately 20% and 35%, when compared to the controls, respectively. The F2R ZsGreen1-1 system revealed to be an efficient assay, which can be used for clinical diagnosis, antiviral resistance evaluation, HSV cycle studies, and new antiviral drug research.

Effects of Standardized Medicinal Plant Extracts on Drug Metabolism Mediated by CYP3A4 and CYP2D6 Enzymes.

The use of medicinal plants concomitantly with conventional drugs can result in herb-drug interactions that cause fluctuations in drug bioavailability and consequent therapeutic failure and/or toxic effects. The CYP superfamily of enzymes plays an important role in herb-drug interactions. Among CYP enzymes, CYP3A4 and CYP2D6 are the most relevant since they metabolize about 50% and 30% of the drugs on the market, respectively. Thus, the main goal of this study was to evaluate the occurrence of in vitro interactions between medicinal plant extracts and drug substrates of CYP3A4 and CYP2D6 enzymes. Standardized extracts from nine medicinal plants (Bauhinia forficata, Cecropia glaziovii, Cimicifuga racemosa, Cynara scolymus, Echinacea sp., Ginkgo biloba, Glycine max, Ilex paraguariensis, and Matricaria recutita) were evaluated for their potential interactions mediated by CYP3A4 and CYP2D6 enzymes. Among the extracts tested, C. glaziovii (red embaúba) showed the most relevant inhibitory effects of CYP3A4 and CYP2D6 activity, while I. paraguariensis (yerba mate) inhibited CYP3A4 activity. Both extracts were chemically analyzed by UPLC-MS/MS, and these inhibitory effects could lead to clinically potential and relevant interactions with the drug substrates of these isoenzymes.

Development of nanoparticles coated with cassava bagasse pectin (Manihot esculenta Crantz) containing ß-carotene for mucoadhesive applications.

Pectin (PC) extracted from a solid residue from cassava roots (Manihot esculenta Crantz) was used to coat nanoparticles (NP) containing ß-carotene (BC) aiming at the gastrointestinal administration of this lipophilic nutraceutical. The NP were prepared by spontaneous emulsification method using food grade components. Pectin-coated NP have been successfully prepared as confirmed by the increased particle size and negative surface charges due to the pectin's anionic nature. NP showed spherical shape and monodisperse distribution, with a mean size of 21.3 nm (polydispersity index (PDI) 0.29) for BC PC T80-NP (nanoparticle with ß-carotene, pectin and Tween 80) and 261.4 nm (PDI 0.1) for BC PC T20-NP (nanoparticle with ß-carotene, pectin and Tween 20). BC was encapsulated at amounts of 530 and 324 µg/ml for BC PC T80-NP and BC PC T20-NP, respectively, with high encapsulation efficiency (> 95%), increasing its antioxidant capacity in vitro, besides no cytotoxic effect. However, only BC PC T20-NP was stable over a 90 days storage period (4°C) and revealed a strong interaction between pectin and mucin. These results suggest that pectin-coated BC PC T20-NP is a promising strategy to improve the bioavailability and permeation of BC for administration through mucosal surfaces.

Different Swine Production Systems Can Shape Slurry Resistome at Mechanism and Class Levels Based on Swine Manure Evaluation.

Antimicrobial resistance is a major threat to public health. Antimicrobial use in animal husbandry is a major concern since it can favor an increase in antimicrobial resistance among farms. Herein, we aim to better understand and characterize the main resistome profiles in microbial communities found in pig farms. Sampling of swine manure was performed in two different timepoints (October 2019 and January 2020) in each of the 14 different swine farms, located in the mesoregion of Western Santa Catarina state in Brazil, a pole of swine product production of worldwide importance. Samples were divided into three groups: farms with the opened regimen and no usage of antimicrobials (F1; n = 10), farms with the closed regimen and usage of antimicrobials (F2; n = 16), and farms with the closed regimen and no usage of antimicrobials (F3; n = 2). The metagenomic evaluation was performed to obtain and identify genetic elements related to antimicrobial resistance using nanopore sequencing. We used ResistoXplorer software to perform composition, alpha and beta diversity, and clustering analysis. In addition, PCR reactions were performed to confirm the presence or absence of seven different beta-lactamase family genes and five phosphoethanolamine transferase gene variants clinically relevant. Our findings based on the identification of resistance genes at the mechanism level showed a prevalence of alteration of the drug target (72.3%) profile, followed by drug inactivation (17.5%) and drug efflux (10.1%). We identified predominantly aminoglycosides (45.3%), tetracyclines (15.9%), and multiclass (11,2%) resistance genes. PCoA analysis indicates differences between F1 and F2 profiles. F2 samples showed increased diversity when compared to the F1 group. In addition, herein we first report the identification of mcr-4 in a slurry sample (C1F1.1) in Santa Catarina State. In general, our findings reinforce that many factors on the practices of animal husbandry are involved in the resistome profile at the mechanism and class levels. Further studies to better understand microbiome and mobilome aspects of these elements are necessary to elucidate transmission pathways between different bacteria and environments.

In Vitro Anti-Trypanosoma cruzi Activity of Halophytes from Southern Portugal Reloaded: A Special Focus on Sea Fennel (Crithmum maritimum L.).

Marine halophytes are an outstanding reservoir of natural products and several species have anti-infectious traditional uses. However, reports about their potential use against neglected tropical ailments, such as Chagas disease, are scarce. This work evaluated for the first time the in vitro anti-Trypanosoma cruzi activity of extracts from the aromatic and medicinal species Helichrysum italicum subsp. picardii (Boiss. & Reut.) Franco (Asteraceae, everlasting) and Crithmum maritimum L. (Apiaceae, sea fennel). For that purpose, decoctions, tinctures, and essential oils from everlasting's flowers and sea fennel's stems, leaves, and flowers were tested against intracellular amastigotes of two T. cruzi strains. The extract from the sea fennel flower decoction displayed significant anti-trypanosomal activity and no toxicity towards the host cell (EC50 = 17.7 µg/mL, selectivity index > 5.65). Subsequent fractionation of this extract afforded 5 fractions that were re-tested in the same model of anti-parasitic activity. Fraction 1 was the most active and selective (EC50 = 0.47 µg/mL, selectivity index = 59.6) and was submitted to preparative thin-layer chromatography. One major compound was identified, falcarindiol, which was likely the one responsible for the observed anti-trypanosomal activity. This was confirmed using a commercially sourced molecule. Target-fishing studies showed falcarindiol as a ligand of T. cruzi spermidine synthase, pointing to a potential enzyme-inhibiting anti-trypanosomal mechanism of action. Overall, this work shows that sea fennel can provide effective anti-parasitic molecule(s) with potential pharmacological applications in the treatment of CD.

Determination of l-(+)-bornesitol, the hypotensive constituent of Hancornia speciosa, in rat plasma by LC-MS/MS and its application on a pharmacokinetic study.

Hancornia speciosa is a medicinal plant with proven antihypertensive activity. The cyclitol l-(+)-bornesitol is the main constituent of its leaves and is a potent inhibitor of the angiotensin-converting enzyme. We herein investigated the pharmacokinetic properties of bornesitol administered orally to Wistar rats, as well as bornesitol permeation in Caco-2 cells. Bornesitol was isolated and purified from an ethanol extract of H. speciosa leaves. An ultra-high performance liquid chromatography coupled with electrospray ionization mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated to quantify bornesitol in rat plasma based on Multiple Reaction Monitoring, using pentaerythritol as an internal standard. Pharmacokinetics was evaluated by the administration of single doses via intravenous in bolus (3 mg/kg) and gavage (3, 15 and 25 mg/kg). Bornesitol permeation was assayed in a transwell Caco-2 cells model, tested alone, or combined with rutin, or as a constituent of H. speciosa extract, using a developed and validated UPLC-ESI-MS/MS method. All assayed validation parameters (selectivity, residual effect, matrix effect, linearity, precision, accuracy and stability of analyte in plasma and solution) for the bioanalytical method met the acceptance criteria established by regulatory guidelines. Bornestiol reached peak plasma concentration within approximately 60 min after oral administration with a half-life ranging from 72.15 min to 123.69 min. The peak concentration and area under the concentration-time curve of bornesitol did not rise proportionally with the increasing doses, suggesting a non-linear pharmacokinetics in rats and the oral bioavailability ranged from 28.5%-59.3%. Bornesitol showed low permeability in Caco-2 cells, but the permeability apparently increased when it was administered either combined with rutin or as a constituent of H. speciosa extract. In conclusion, bornesitol was rapidly absorbed after a single oral administration to rats and followed a non-linear pharmacokinetics. The obtained data will be useful to guide further pre-clinical development of bornesitol-containing herbal preparations of H. speciosa as an antihypertensive agent.

Matrix effects of the hydroethanolic extract and the butanol fraction of calyces from Physalis peruviana L. on the biopharmaceutics classification of rutin.

OBJECTIVES: The Biopharmaceutics Classification System (BCS) categorizes active pharmaceutical ingredients according to their solubility and permeability properties, which are susceptible to matrix or formulation effects. The aim of this research was to evaluate the matrix effects of a hydroethanolic extract of calyces from Physalis peruviana L. (HEE) and its butanol fraction (BF), on the biopharmaceutics classification of their major compound, quercetin-3-O-rutinoside (rutin, RU). METHODS: Rutin was quantified by HPLC-UV, and Caco-2 cell monolayer transport studies were performed to obtain the apparent permeability values (Papp ). Aqueous solubility was determined at pH 6.8 and 7.4. KEY FINDINGS: The Papp values followed this order: BF > HEE > RU (1.77 ± 0.02 > 1.53 ± 0.07 > 0.90 ± 0.03 × 10-5  cm/s). The lowest solubility values followed this order: HEE > RU > BF (2.988 ± 0.07 > 0.205 ± 0.002 > 0.189 ± 0.005 mg/ml). CONCLUSIONS: According to these results, rutin could be classified as BCS classes III (high solubility/low permeability) and IV (low solubility/low permeability), depending on the plant matrix. Further work needs to be done in order to establish how apply the BCS for research and development of new botanical drugs or for bioequivalence purposes.

Reviewing the mechanisms of natural product-drug interactions involving efflux transporters and metabolic enzymes.

The World Health Organization (WHO) and other worldwide health agencies have recently taken initiatives to encourage the use of traditional medicine and/or complementary/alternative medicine in order to promote well-being and public health. In this way, one of the WHO's concerns is the safe use of these therapies. Phytotherapy is a strategy consisting of the use of medicinal plants (MP) and/or herbal medicinal products (HMP) for medicinal purposes. The use of phytotherapy concomitantly with drugs may cause interactions compromising the expected pharmacological action or generating toxic effects. These interactions are complex processes that may occur with multiple medications targeting different metabolic pathways, and involving different compounds present in MP and HMP. Thus, the aim of this review was to summarize the main MP- and HMP-drug interactions that involve specific transporters (P-glycoprotein and BCRP) and CYP450 enzymes (CYP3A4 and CYP2D6), which play relevant roles in the mechanisms of interactions. Firstly, multiple databases were used to search studies describing in vitro or in vivo MP and HMP-drug interactions and, after that, a systematic note-taking and appraisal of the literature was conducted. It was observed that several MP and HMP, metabolic pathways and transcription factors are involved in the transporters and enzymes expression or in the modulation of their activity having the potential to provide such interactions. Thus, the knowledge of MP- and HMP-drug interaction mechanisms could contribute to prevent harmful interactions and can ensure the safe use of these products to help the establishment of the therapeutic planning in order to certify the best treatment strategy to be used.

Development of Caco-2 cells-based gene reporter assays and evaluation of herb-drug interactions involving CYP3A4 and CYP2D6 gene expression.

The indiscriminate use of medicinal plants and herbal medicinal products concomitantly with conventional drugs may result in herb-drug interactions that may lead to fluctuations in drug bioavailability, therapeutic failure, and/or toxic effects. CYP450 enzymes play an important role in drug biotransformation and herb-drug interactions. Thus, the aim of this study was to develop and apply Caco-2 cells-based gene reporter assays to study in vitro the potential occurrence of CYP3A4 and CYP2D6 gene expression modulation by standardized extracts of selected medicinal plants. Reporter cell lines developed showed a significant increase in CYP3A4 and CYP2D6 reporter fluorescent emission, 4 and 16-fold respectively, when compared to the controls. The standardized extracts of Cecropia glaziovii, Bauhinia forficata and Echinacea sp. significantly increased CYP3A4 reporter fluorescence, and those of Ilex paraguariensis, Bauhinia forficata and Echinacea sp. significantly decreased CYP2D6 reporter fluorescence in Caco-2 cells-based gene reporter assays. The data obtained suggest that CYP3A4 and CYP2D6 gene expression seem to be modulated by the extracts tested. In addition, the reporter cell lines developed are functional assays that could be used to study drug-drug and herb-drug interactions during the research and development of new drugs.

Antimutagenic and antiherpetic activities of different preparations from Uncaria tomentosa (cat's claw).

Uncaria tomentosa have been used to treat viral diseases such as herpes due to multiple pharmacological effects, but its therapeutic efficacy against this virus have not been reported yet. Thus, in vitro antiherpetic activity of hydroethanolic extract from barks, purified fractions of quinovic acid glycosides and oxindole alkaloids was evaluated by plaque reduction assay, including mechanistic studies (virucidal, attachment and penetration action). Once exposure to physical agents might lead to reactivation of the herpetic infection, antimutagenic effect (pre-, simultaneous and post-treatment protocols) was also evaluated by Comet assay. The antiherpetic activity from the samples under investigation seemed to be associated with the presence of polyphenols or their synergistic effect with oxindole alkaloids or quinovic acid glycosides, once both purified fractions did not present activity when evaluated alone. Inhibition of viral attachment in the host cells was the main mechanism of antiviral activity. Although both purified fractions displayed the lowest antimutagenic activity in pre and simultaneous treatment, they provided a similar effect to that of cat's claw hydroethanolic extract in post-treatment. Given that purified fractions may result in a reduced antiherpetic activity, the use of cat's claw hydroethanolic extract from barks should be prioritized in order to obtain a synergistic effect.