Cellular toxicity and DNA damage induced by Newbouldia laevis used for male infertility treatment in prokaryotic and eukaryotic models.

Leaves of Newbouldia laevis have been extensively used in solving problems associated with infertility and childbirth in many African countries. Yet, information is very limited on the DNA damaging potential of this plant. This study evaluated the cytogenotoxic effect of the aqueous extract of N. laevis leaf using prokaryotic models (Ames Salmonella fluctuation test using TA100 and TA98 strains of Salmonella typhimurium and SOS Chromotest with Escherichia coli PQ37) and eukaryotic model (Allium cepa root cells). Identification of the volatile organic compounds (VOCs) and phytochemical screening of the plant extract were also performed. Onion bulbs were grown on each concentration (1 to 50%; v/v, extract/tap water) of the extract for chromosomal aberrations and root growth analyses. Results of the Ames test indicated that the extract is mutagenic while the SOS Chromotest results showed good complementation to the Ames test results, although the E. coli PQ37 system showed slightly higher sensitivity in the detection of mutagenicity and genotoxicity of the extract. The plant extract was cytotoxic when compared to the control, inducing a significant (p < 0.05) concentration-dependent inhibition of root growth from 5 to 50% concentrations. At 50% concentration, the extract completely inhibited cell division in the A. cepa. Also, chromosomal aberration increased significantly (p < 0.05) in exposed onions from 5 to 20% concentrations. The mutagenicity and cytogenotoxicity recorded in this report were believed to be caused by the presence of VOCs such as 1,2,3-benzene-triol, 1,2-benzenediol, and 5-hydroxymethylfurfural, and alkaloids in the extract an indication of the cytogenotoxicity of the aqueous extract of N. laevis leaf even at low concentration.

Toxicological potential of Aloysia gratissima: Insights from chemical analysis and in vitro studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Aloysia gratissima leaves are popularly used to treat respiratory, digestive, and nervous system disorders. Several studies have been carried out to determine the biological activity of A. gratissima, such as its antibacterial and anti-edematogenic activities, but despite the beneficial uses of A. gratissima, few studies have examined the toxicological profile of this plant. AIM OF THE STUDY: This study aimed to determine the chemical composition, cytotoxic, genotoxic, mutagenic potential, and antioxidant activity of an aqueous extract of A. gratissima leaves (AG-AEL). MATERIAL AND METHODS: The phytochemical constitution of AG-AEL was assessed by colorimetric analyses and High-performance liquid chromatography (HPLC). The inorganic elements were detected by Particle-Induced X-ray Emission (PIXE). The antioxidant, cytotoxicity, genotoxic, and mutagenic activities were evaluated in vitro by Di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH), Sulforhodamine B (SRB) assay, comet assay, and Salmonella/microsome assays. RESULTS: AG-AEL indicated the presence of terpenoids, flavonoids, and phenolic acids. HPLC detected rutin at 2.41 ± 0.33 mg/100 mg. PIXE analysis indicated the presence of Mg, Si, P, S, K, Ca, Mn, and Zn. The 50% inhibitory concentration was 84.17 ± 3.17 µg/mL in the DPPH assay. Genotoxic effects were observed using the Comet assay in neuroblastoma (SH-SY5Y) cells and mutations were observed in TA102 and TA97a strains. The extract showed cytotoxic activities against ovarian (OVCAR-3), glioblastoma (U87MG), and colon (HT-29) cancer cell lines. CONCLUSIONS: In conclusion, AG-AEL increased DNA damage, induced frameshift, and oxidative mutations, and showed cytotoxic activities against different cancer cells. The in vitro toxicological effects observed suggest that this plant preparation should be used with caution, despite its pharmacological potential.

The mutagenic effect of tobacco smoke on male fertility.

Despite the association between tobacco use and the harmful effects on general health as well as male fertility parameters, smoking remains globally prevalent. The main content of tobacco smoke is nicotine and its metabolite cotinine. These compounds can pass the blood-testis barrier, which subsequently causes harm of diverse degree to the germ cells. Although controversial, smoking has been shown to cause not only a decrease in sperm motility, sperm concentration, and an increase in abnormal sperm morphology, but also genetic and epigenetic aberrations in spermatozoa. Both animal and human studies have highlighted the occurrence of sperm DNA-strand breaks (fragmentation), genome instability, genetic mutations, and the presence of aneuploids in the germline of animals and men exposed to tobacco smoke. The question to be asked at this point is, if smoking has the potential to cause all these genetic aberrations, what is the extent of damage? Hence, this review aimed to provide evidence that smoking has a mutagenic effect on sperm and how this subsequently affects male fertility. Additionally, the role of tobacco smoke as an aneugen will be explored. We furthermore aim to incorporate the epidemiological aspects of the aforementioned and provide a holistic approach to the topic.

Subacute oral toxicity and bacterial mutagenicity of a mixture of Puerariae radix and Hizikia fusiforme extracts.

The study aims to identify the safety profile of a mixed extract (KGC-02-PS) from two traditional medicinal herbs, Puerariae radix and Hizikia fusiforme. In a subacute oral toxicity study, KGC-02-PS was administered orally for 28 days by gavage to Sprague Dawley rats (both sexes) at a daily dose of 0, 500, 1000, and 2000 mg/kg body weight. Bodyweight, food consumption, and clinical signs were monitored during the experimental period. After administering the final dose, this study conducted hematology, serum biochemistry, and pathological evaluations. In addition, the study performed a bacterial reverse mutation test with varying concentrations of KGC-02-PS (312.5 µg - 5,000 µg/plate) following OECD guideline No. 471, before testing five bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2) in the presence or absence of metabolic activation. The preclinical evaluation of KGC-02-PS's subacute oral toxicity yielded no associated toxicological effects or any changes in clinical signs, body weight, and food consumption. Moreover, examining KGC-02-PS's hematological and serum biochemical characteristics and pathology yielded no toxicological changes in terms of organ weight measurements and gross or histopathological findings. KGC-02-PS neither increased the number of revertant colonies in all bacterial strains used in the bacterial reverse mutation test, nor did it induce genotoxicity related to bacterial reverse mutations under the study's conditions. Also, KGC-02-PS's no-observed-adverse-effect level was greater than 2000 mg/kg.

Synthesis of silver nanoparticles using Ziziphus nummularia leaf extract and evaluation of their antimicrobial, antioxidant, cytotoxic and genotoxic potential (4-in-1 system).

This study reports the synthesis of silver nanoparticles (AgNPs) from silver nitrate by leaf extract of a medicinal plant Ziziphus nummularia. The leaf extract acts as a reducing and stabilizing agent for the formation of nanoparticles. The green synthesized AgNPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared (FITR) spectroscopy, Thermogravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM) analysis and evaluated their antimicrobial, antioxidant, cytotoxic and genotoxic potential. The UV-Vis spectroscopy showed a characteristic absorption peak at 430 nm due to surface plasma resonance. TEM analysis showed that synthesized AgNPs were spherical and oval with an average size of 25.96 nm. AgNPs showed effective antimicrobial activity (lowest MIC-0.625 µg/mL against Escherichia coli), synergistic antimicrobial activity (lowest ΣFIC 0.09 with chlormaphenicol against Corynebacterium rubrum) and antibiofilm activity. AgNPs showed strong DPPH activity with IC50 - 520 µg/mL and ABTS activity IC50 - 55 µg/mL and reducing capacity assessment. In vitro cytotoxic effect was evaluated by MTT assay against HeLa cells, breast cells and fibroblast cells. Genotoxic effect was evaluated by comet assay. AgNPs displayed dose-dependent cytotoxic and genotoxic effect. Our findings indicated that synthesized AgNPs could be considered as multifunctional and have great potential for use in biomedical applications.HighlightsSilver nanoparticles were synthesized using leaf extract of Ziziphus nummulariaCharacterization was done by various spectral techniquesAntimicrobial efficacy was demonstrated against an array of bacteriaAgNPs exhibited significant cytotoxic effect against HeLa cell lineAgNPs showed cytotoxicity and genotoxicity in a dose-dependent manner.

Preventive activity of Copaifera langsdorffii Desf. leaves extract and its major compounds, afzelin and quercitrin, on DNA damage in in vitro and in vivo models.

Copaifera langsdorffii Desf. is a plant found in South America, especially in Brazil. Oleoresin and the leaves of this plant is used as a popular medicinal agent. However, few studies on the chemical composition of aerial parts and related biological activities are known. This study aimed to examine the cytotoxic, genotoxic, and antigenotoxic potential of C. langsdorffii aerial parts hydroalcoholic extract (CLE) and two of its major compounds afzelin and quercitrin. The cytotoxic and antigenotoxic potential of CLE was determined as follows: 1) against genotoxicity induced by doxorubicin (DXR) or methyl methanesulfonate (MMS) in V79 cells; 2) by direct and indirect-acting mutagens in Salmonella typhimurium strains; and 3) by MMS in male Swiss mice. The protective effects of afzelin and quercitrin against DXR or MMS were also evaluated in V79 and HepG2 cells. CLE was cytotoxic as evidenced by clonogenic efficiency assay. Further, CLE did not induce a significant change in frequencies of chromosomal aberrations and micronuclei; as well as number of revertants in the Ames test demonstrating absence of genotoxicity. In contrast, CLE was found to be antigenotoxic in mammalian cells. The results also showed that CLE exerted inhibitory effect against indirect-acting mutagens in the Ames test. Afzelin and quercitrin did not reduce genotoxicity induced by DXR or MMS in V79 cells. However, treatments using afzelin and quercitrin decreased MMS-induced genotoxicity in HepG2 cells. The antigenotoxic effect of CLE observed in this study may be partially attributed to the antioxidant activity of the combination of major components afzelin and quercitrin.

Evaluation of the cytotoxic and genotoxic effects of Sida planicaulis Cav extract using human neuroblastoma cell line SH-SY5Y.

Sida planicaulis is a weed thought to have originated in Brazil, where it is present in abundant quantities, but also this plant is also found in south-central Florida, Indian Ocean Islands, and the Pacific Islands. Sida planicaulis produces neurotoxicity that adversely affects livestock breeding with heavy animal losses and consequent negative impact on Brazil's economy. The aim of this study was to determine the chemical profile, cytotoxic and genotoxic effects of ethanolic extracts of S. planicaulis collected in winter (leaf extract) and summer (leaf extract and leaf + flower extract) using an in vitro model of human neuroblastoma cell line SH-SY5Y. Phytochemical screening demonstrated the presence of alkaloids, flavonoids, and apolar compounds. Rutin, quercetin, and swainsonine were detected by HPLC and GC/MS, respectively. Phosphorus, potassium, iron, and zinc were the inorganic elements found. Extracts produced cytotoxicity at all concentrations tested (7-4,000 µg/ml) as evidenced by the colorimetric assay [3-(4,5-dimethyl-thiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT)]. Based upon the alkaline comet assay extracts were found to induce genotoxicity at concentrations ranging from 0.437 to 7 µg/ml. DNA damage produced by extracts was affirmed using a modified comet assay with the enzymes Endo III and FPG in a concentration dependent manner. Further, enzyme-modified comet assay showed both oxidized purines and pyrimidines, and consequently oxidative stress was related to genomic instability and cell death. Data suggest that low concentrations of ethanolic extracts of S. planicaulis (different seasons) induced increased DNA damage related to oxidative stress and chemical composition.

Mutagenic and cytostatic activities of the Xylopia laevigata essential oil in human lymphocytes.

Hydro-distilled essential oil from leaves of Xylopia laevigata was characterized by GC-MS. Twenty-seven components were identified and the oil's major constituents comprised germacrene D, bicyclogermacrene, (E)-caryophyllene and germacrene B. The cytotoxicity of the essential oil of X. laevigata (EOXL), determined by MTT and mitotic index methods in cultured human lymphocytes was observed in all tested concentrations. Cultures treated with EOXL demonstrated significant increase in the frequencies of micronuclei in the cytokinesis-block micronucleus assay (CBMN) and reduction of the cytokinesis-block proliferation index (CBPI) rates. Results demonstrated the cytostatic and mutagenic effects of EOXL, the latter for the first time.

Mutagenic potential of medicinal plants evaluated by the Ames Salmonella/microsome assay: A systematic review.

The Ames test has become one of the most commonly used tests to assess the mutagenic potential of medicinal plants since they have several biological activities and thus have been used in traditional medicine and in the pharmaceutical industry as a source of raw materials. Accordingly, this review aims to report previous use of the Ames test to evaluate the mutagenic potential of medicinal plants. A database was constructed by curating literature identified by a search on the electronic databases Medline (via Pubmed), Science Direct, Scopus, and Web of Science from 1975 to April 2020, using the following terms: "genotoxicity tests" OR "mutagenicity tests" OR "Ames test" AND "medicinal plants." From the research, 239 articles were selected, including studies of 478 species distributed across 111 botanical families, with Fabaceae, Asteraceae and Lamiaceae being the most frequent. It was identified that 388 species were non-mutagenic. Of these, 21% (83/388) showed antimutagenic potential, most notable in the Lamiaceae family. The results also indicate that 18% (90/478) of the species were mutagenic, of which 54% were mutagenic in the presence and absence of S9. Strains TA98 and TA100 showed a sensitivity of 93% in detecting plant extracts with mutagenic potential. However, the reliability of many reviewed studies regarding the botanical extracts may be questioned due to technical issues, such as testing being performed only in the presence or absence of S9, use of maximum doses below 5 mg/plate and lack of information on the cytotoxicity of tested doses. These methodological aspects additionally demonstrated that a discussion about the doses used in research on mixtures, such as the ones assessed with botanical extracts and the most sensitive strains employed to detect the mutagenic potential, should be included in a possible update of the guidelines designed by the regulatory agencies.

Protective Role of Glutathione against Peroxynitrite-Mediated DNA Damage During Acute Inflammation.

Inflammation is an immune response to protect against various types of infections. When unchecked, acute inflammation can be life-threatening, as seen with the current coronavirus pandemic. Strong oxidants, such as peroxynitrite produced by immune cells, are major mediators of the inflammation-associated pathogenesis. Cellular thiols play important roles in mitigating inflammation-associated macromolecular damage including DNA. Herein, we have demonstrated a role of glutathione (GSH) and other thiols in neutralizing the effect of peroxynitrite-mediated DNA damage through stable GSH-DNA adduct formation. Our observation supports the use of thiol supplements as a potential therapeutic strategy against severe COVID-19 cases and a Phase II (NCT04374461) open-label clinical trial launched in early May 2020 by the Memorial Sloan Kettering Cancer Center.

Toward clinical understanding of aristolochic acid upper-tract urothelial carcinoma.

A cluster of patients poisoned by herbal medicine in the 1990s revealed that aristolochic acid (AA) causes kidney failure and upper tract urothelial carcinoma (UTUC). Recent research demonstrated that this was not an isolated incident; on the contrary, AA exposure is widespread in East Asia. This editorial highlights research by Lu and colleagues that investigates clinical characteristics of AA and non-AA UTUCs from 90 patients in Beijing based on the AA mutational signature. The study also detected AA mutations in non-tumor tissue of AA exposed patients and showed that AA mutations can be detected in urine, which might form the basis for non-invasive tests for AA exposure.

EMS Mutagenesis of Maize Pollen.

Effective mutagenesis is critical for connecting traits of interest to specific plant genes. The development of site-directed mutagenesis and sequenced-indexed genetics resources in maize allows for targeted analysis of individual genes. These reverse genetics approaches have the potential for confirmation bias by only studying candidate genes for association with traits of interest. Genetic screens of induced, random mutations are important for identifying novel loci as well as interacting factors for known mutant loci. Chemical mutagenesis provides very high mutation rates and can be used for a variety of screen designs. This chapter provides an updated protocol for ethyl methanesulfonate (EMS) mutagenesis of maize pollen using paraffin or mineral oil. Mutagenesis occurs in mature pollen causing nonconcordant endosperm and embryo genotypes as well as sectored M1 plants. Considerations for these factors in genetic screens are discussed.

Cytotoxic and genotoxic effects of an endemic plant of Turkey Salvia kronenburgii on breast cancer cell lines.

CONTEXT: The natural products derived from plants are the important sources that can be used for breast cancer treatment. Salvia species and their derived products were recommended as potential antitumor substances. AIM: The potential cytotoxic and genotoxic effects of Salvia kronenburgii have been investigated on breast cancer cell lines, MCF-7 and MDA-MB-231. MATERIALS AND METHODS: Determination of chemical compounds of S. kronenburgii was done using a gas chromatography coupled to time-of-flight mass spectrometry system and a dual-stage commercial thermal desorption injector. Growth inhibition of the S. kronenburgii was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and ATP viability assays. The cell death mode was detected by fluorescent dyes. Genotoxic effect of S. kronenburgii was measured by comet assay. RESULTS: S. kronenburgii showed antiproliferative effect in a dose-dependent manner on MCF-7 and MDA-MB-231 cell lines by inducing apoptosis-like cell death. The pyknotic cell nuclei were observed at the cell lines in response to S. kronenburgii. Furthermore, significant increase was shown in genetic damage index and frequencies in the damaged cells. CONCLUSION: S. kronenburgii might be a promising natural source for cancer therapy. Further experiments need to be done in vivo to understand of the anticancer effects of this plant.

Modulation of hepatic ABC transporters by Eruca vesicaria intake: Potential diet-drug interactions.

The aim of this work was to evaluate whether oral administration of Eruca vesicaria, a species of rocket cultivated in Argentina, could modify cyclophosphamide (CP)-induced genotoxicity through modulation of hepatic ABC transporters. Daily oral administration of E. vesicaria fresh leaves juice (1.0, 1.4 and 2.0  g/kg) for 14 days did not alter genotoxicity biomarkers -alkaline comet assay and micronucleus test -in neither male nor female mice. Instead, repeated intake of this cruciferous decreased CP-induced DNA damage dose-dependently and it caused hepatic overexpression of P-glycoprotein (P-gp; 1.4 and 2.0  g/kg) and multidrug resistance protein 2 (MRP2; 2.0  g/kg), but not breast cancer resistance protein (Bcrp). The antigenotoxic effect of E. vesicaria was prevented by 50 mg/kg verapamil (P-gp inhibitor) or 10 mg/kg indomethacin (MRP2 inhibitor). In turn, CP-induced cytotoxicity (10 mM, 24 h) on human hepatoma cells (HepG2/C3A) was significantly reduced by preincubation with E. vesicaria (1.4 mg/ml; 48 h); this effect was absent when CP was coincubated with 35 µM verapamil, 80 µM indomethacin or 10 µM KO-143 (BCRP inhibitor). Altogether, these results allow us to demonstrate that repeated intake of E. vesicaria exhibited antigenotoxicity, at least in part, by induction of hepatic ABC transporters in vivo in mice as well as in vitro in human liver cells. This could account for other diet-drug interactions.

Pectin/Chitosan/Tripolyphosphate Nanoparticles: Efficient Carriers for Reducing Soil Sorption, Cytotoxicity, and Mutagenicity of Paraquat and Enhancing Its Herbicide Activity.

As a potent herbicide capable of contaminating water and soil environments, paraquat, which is still widely used worldwide, is toxic to mammals, algae, aquatic animals, etc. Paraquat was loaded on novel nanoparticles composed of pectin, chitosan, and sodium tripolyphosphate (PEC/CS/TPP). The size, polydispersity index, and ζ potential of nanoparticles were characterized. Further assessments were carried out by SEM, AFM, FT-IR, and DSC. The encapsulation was highly efficient, and there was a delayed release pattern of paraquat. The encapsulated herbicide was less toxic to alveolar and mouth cell lines. Moreover, the mutagenicity of the formulation was significantly lower than those of pure or commercial forms of paraquat in a Salmonella typhimurium strain model. The soil sorption of paraquat and the deep soil penetration of the nanoparticle-associated herbicide were also decreased. The herbicidal activity of paraquat for maize or mustard was not only preserved but also enhanced after encapsulation. It was concluded that paraquat encapsulation with PEC/CS/TPP nanoparticles is highly efficient and the formulation has significant herbicide activity. It is less toxic to human environment and cells, as was evidenced by less soil sorption, cytotoxicity, and mutagenicity. Hence, paraquat-loaded PEC/CS/TPP nanoparticles have potential advantages for future use in agriculture.

Cytotoxic and Genotoxic Activities of Alkaloids from the Bulbs of Griffinia gardneriana and Habranthus itaobinus (Amaryllidaceae).

BACKGROUND: Amaryllidaceae plants are known to be a great source of alkaloids, which are considered an extensive group of compounds encompassing a wide range of biological activities. The remarkable cytotoxic activities observed in most of the Amaryllidaceae alkaloids derivatives have prompt the chemical and biological investigations in unexplored species from Brazil. OBJECTIVE: To evaluate the cytotoxic and genotoxic properties of alkaloids of Griffinia gardneriana and Habranthus itaobinus bulbs and study the role of caspase-3 as a molecular apoptosis mediator. METHODS: Methanolic crude extracts of Griffinia gardneriana and Habranthus itaobinus bulbs were submitted to acid-base extraction to obtain alkaloid-enriched fractions. The obtained fractions were fractionated using chromatographic techniques leading to isolation and identification of some alkaloids accomplished via HPLC and 1H-NMR, respectively. Molecular docking studies assessed the amount of free binding energy between the isolated alkaloids with the caspase-3 protein and also calculated the theoretical value of Ki. Studies have also been developed to evaluate in vitro cytotoxicity and genotoxicity in such alkaloids and apoptosis activation via the caspase pathway using both tumor and normal cell lines. RESULTS: Seven alkaloids were isolated and identified. Among these, 11-hydroxyvittatine and 2-α-7- dimethoxyhomolycorine were not cytotoxic, whereas tazettine, trisphaeridine, and sanguinine only showed activity against the fibroblast lineage. Lycorine and pretazettine were 10 to 30 folds more cytotoxic than the other alkaloids, including cancerous lines, and were genotoxic and capable of promoting apoptosis via the caspase-3 pathway. This result supports data obtained in docking studies wherein these two compounds exhibited the highest free energy values. CONCLUSION: The cytotoxicity assay revealed that, among the seven alkaloids isolated, only lycorine and pretazettine were active against different cell lines, exhibiting concentration- and time-dependent cytotoxic actions alongside genotoxic action and the ability to induce apoptosis by caspase-3, a result consistent with those obtained in docking studies.

Evaluation of genotoxic and modulatory effects of Nyctanthes arbor-tristis calyx extract and the isolated crocin in Ames' assay.

Flowers of the plant Nyctanthes arbor-tristis (NAT) are widely used in the traditional medicinal systems of several Asian countries. In the present study, potential genotoxicity and modulatory effects of ethanolic extract of NAT flower calyx (NAT FCE) and crocin, a carotenoid principle were evaluated employing standard Salmonella assay. Experiments evaluating the genotoxic potential of NAT FCE and crocin, with and without the S9-activation in TA 98, TA 100 and TA 102 showed a lack of increase in revertant mutants. Evaluation of modulatory effects of NAT FCE and crocin, without the S9, showed significant decrease in the number of 4-nitro-o-phenylenediamine-, sodium azide- and ethyl methanesulfonate-induced revertants. However, with S9, NAT FCE and crocin moderately increased the 2-aminoanthracene-induced revertants in TA 98; they moderately decreased revertants in TA 100 and TA 102. Both NAT FCE and crocin have been shown to be non-genotoxic and to be able to modulate responses of standard mutagens.

Mutagenicity of Ayahuasca and Their Constituents to the Salmonella/Microsome Assay.

Ayahuasca is a beverage used in religious rituals of indigenous and nonindigenous groups, and its therapeutic potential has been investigated. Ayahuasca is obtained by decoction of the Banisteriopsis caapi that contains ß-carbolines (harmine, harmaline, and tetrahydroharmine) plus Psychotria viridis that contains N,N-dimethyltryptamine. Although plants used in folk medicine are recognized as safe, many of them have genotoxic potential. The Salmonella/microsome assay is usually the first line of the mutagenicity evaluation of products intended for therapeutic use. Our objective was to evaluate the mutagenicity of ayahuasca beverage and their constituents using the Salmonella/microsome assay with TA98 and TA100. We analyzed two ayahuasca samples, and also beverage samples prepared each individual plant P. viridis and B. caapi. Harmine and harmaline were also tested. All beverage samples were chemically characterized and both ayahuasca samples could be considered representative of the beverages consumed in religious rituals. Both ayahuasca samples were mutagenic for TA98 and TA100 with and without S9, with similar potencies. The beverage obtained from P. viridis was not mutagenic, and beverage obtained from B. caapi was mutagenic for TA98 with and without S9. Harmine was nonmutagenic and harmaline was mutagenic only for TA98 without S9. Harmaline fully explain the mutagenicity observed with TA98 without S9 of both ayahuasca samples and the B. caapi beverage samples. We conclude that the ayahuasca samples are mutagenic and this effect is partially explained by harmaline, one of the ß-carbolines present in the beverage. Other mutagenic compounds seem to be present and need to be further investigated. Environ. Mol. Mutagen. 60:269-276, 2019. © 2018 Wiley Periodicals, Inc.

Attenuation of autophagy flux by 6-shogaol sensitizes human liver cancer cells to TRAIL-induced apoptosis via p53 and ROS.

Tumor necrosis factor (TNF)­related apoptosis­inducing ligand (TRAIL) is a member of the TNF superfamily and is an antitumor drug that induces apoptosis in tumor cells with minimal or no effects on normal cells. Here, it is demonstrated that 6­shogaol (6­sho), a bioactive component of ginger, exerted anti­inflammatory and anticancer properties, attenuated tumor cell propagation and induced TRAIL­mediated cell death in liver cancer cells. The current study identified a potential pathway by revealing that TRAIL and 6­sho or chloroquine acted together to trigger reactive oxygen species (ROS) production, to upregulate tumor­suppressor protein 53 (p53) expression and to change the mitochondrial transmembrane potential (MTP). Treatment with N­acetyl­L­cysteine reversed these effects, restoring the MTP and attenuated ROS production and p53 expression. Interestingly, treatment with 6­sho increased p62 and microtubule­associated proteins 1A/1B light chain 3B­II levels, indicating an inhibited autophagy flux. In conclusion, attenuation of 6­sho­induced autophagy flux sensitized cells to TRAIL­induced apoptosis via p53 and ROS, suggesting that the administration of TRAIL in combination with 6­sho may be a suitable therapeutic method for the treatment of TRAIL­resistant Huh7 liver cells.

In vitro and in vivo evaluation of enzymatic and antioxidant activity, cytotoxicity and genotoxicity of curcumin-loaded solid dispersions.

Curcumin, the main bioactive polyphenolic compound in Curcuma longa L. rhizomes has a wide range of bioactive properties. Curcumin presents low solubility in water and thus limited bioavailability, which decreases its applicability. In this study, cytotoxic effects of curcumin solid dispersions (CurSD) were evaluated against tumor (breast adenocarcinoma and lung, cervical and hepatocellular carcinoma) and non-tumor (PLP2) cells, while cytotoxic and genotoxic effects were evaluated in Allium cepa. The effect of the CurSD on the acetylcholinesterase (AChE), butyrylcholinesterase (BChE), glutathione S-transferase (GST), and monoamine oxidase (MAO A-B) enzymes was determined, as well as its capacity to inhibit the oxidative hemolysis (OxHLIA) and the formation of thiobarbituric acid reactive substances (TBARS). CurSD are constituted by nanoparticles that are readily dispersible in water, and inhibited 24% and 64% of the AChE and BChE activity at 100 µM, respectively. GST activity was inhibited at 30 µM while MAO-A and B activity were inhibited at 100 µM. CurSD showed cytotoxicity against all the tested tumor cell lines without toxic effects for non-tumor cells. No cytotoxic and genotoxic potential was detected with the Allium cepa test. CurSD maintained the characteristics of free curcumin on the in vitro modulation of important enzymes without appreciable toxicity.