Glucosinolate-Enriched Fractions from Maca (Lepidium meyenii) Exert Myrosinase-Dependent Cytotoxic Effects against HepG2/C3A and HT29 Tumor Cell Lines.

The consumption of glucosinolate (GL)-rich foods, including Brassica vegetables, such as mustard, broccoli, and maca, is associated with decreased risk of developing cancer. The GL content in maca, which is recognized as a "superfood", is approximately 100-times higher than that in other brassicas. Although maca is a potential dietary source of GLs, limited studies have examined the bioactivity of maca GLs using the combination of chemical characterization and bioassays. In this study, the fractions (Lm-II and Lm-III) rich in intact GLs (glucotropaeolin and glucolimnanthin) were isolated and characterized from maca ethanolic extracts using chromatography and mass spectrometry. Additionally, the growth-inhibitory effects of Lm-II and Lm-II fractions against hepatocellular carcinoma (HepG2/C3A) and colon adenocarcinoma (HT29) cell lines were examined in the absence or presence of myrosinase (MYR). Fractions lacking low molecular weight sugars dose-dependently exerted cytotoxic effects in the presence of MYR. The half-maximal inhibitory concentration values of Lm-II and Lm-III against HepG2/C3A were 118.8 and 69.9 µg/mL, respectively, while those against HT29 were 102.6 and 71.5 µg/mL, respectively. These results suggest that the anticancer properties of maca can be attributed to GLs and corroborate the categorization of maca as a "superfood."Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.1952444.

Genistein Affects Expression of Cytochrome P450 (CYP450) Genes in Hepatocellular Carcinoma (HEPG2/C3A) Cell Line.

BACKGROUND: Genistein (5,7-Dihydroxy-3-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) is the most abundant isoflavone in soybean, which has been associated with a lower risk of development of cancer and cardiovascular diseases. Of particular interest regarding cancer preventive properties of flavonoids is their interaction with cytochrome P450 enzymes (CYPs). However, contradictory data report the effect of genistein on expression of СYPs enzymes. OBJECTIVE: The aim of this study was to investigate the effects of genistein on cytochrome P450 (CYP) gene expression levels in human hepatocellular carcinoma (HepG2/C3A) and colon adenocarcinoma (HT29) cells. METHODS: Real-time RT-PCR was used to examine the expression of genes families involved in xenobiotic metabolism, such as CYP1 (CYP1A1, CYP1B1), CYP2 (CYP2E1, CYP2D6), CYP3 (CYP3A4); and of a family involved in the catabolism of the all-trans-retinoic acid (ATRA), CYP26 (CYP26A1, CYP26B1). RESULTS: RT-qPCR data analysis showed that after 12 h of exposure of HepG2/C3A cells to genistein (5 and 50 µM) there was an upregulation of CYP1A1 and CYP1B1 and downregulation of CYP2D6, CYP26A1 and CYP26B1 mRNA levels. There was no change in the mRNA levels of CYP P450 genes in HT29 cells. CONCLUSION: Our results suggest that treatment with genistein in non-toxic concentrations may impact the expression level of CYPs involved in the biotransformation of xenobiotics and drug metabolizing enzymes. Moreover, the downregulation of ATRA metabolism-related genes opens a new research path for the study of genistein as retinoic acid metabolism blocking agent for treating cancer and other pathologies.

Genistein at maximal physiologic serum levels induces G0/G1 arrest in MCF-7 and HB4a cells, but not apoptosis.

Several studies have demonstrated that a balanced diet can contribute to better human health. For this reason, soy-based food and pure isoflavones (pills) are one of the most consumed. The association of this consumption and lower risks of chronic diseases and cancer is well established for the Asian population and has been attracting the attention of people worldwide, especially women at menopause who seek to alleviate the symptoms associated with the lack of estrogen. Despite positive epidemiological data, concerns still exist because of conflicting results found in scientific literature with relation to the role of isoflavones in breast and hormone-related cancers. The aim of our study was to investigate the cytotoxicity, induction of apoptosis, and changes in apoptosis-related genes of maximal physiological serum levels of the isoflavone genistein (Gen) in MCF-7 tumoral cells and in HB4a non-tumoral cells. In addition, induction of cell cycle arrest was also investigated. Only supraphysiological levels of Gen (50 and 100 µM) were cytotoxic to these cell lines. Concentrations of 10 and 25 µM did not induce apoptosis and significant changes in expression of the studied genes. Positive results were found only in cell cycle analysis: G0/G1 delay of MCF-7 cells in both concentrations of Gen and at 25 µM in HB4a cells. It is the first study investigating effects of Gen in the HB4a cell line. Thus, despite the lack of apoptosis induction (generally found with high concentrations), Gen at physiologically relevant serum levels still exerts chemopreventive effects through the modulation of cell cycle.

In vitro evaluation of the genotoxic activity and apoptosis induction of the extracts of roots and leaves from the medicinal plant Coccoloba mollis (Polygonaceae).

Coccoloba mollis (Family Polygonaceae) is a medicinal plant popularly used in cases of memory loss, stress, insomnia, anemia, impaired vision, and sexual impotence, but the scientific literature, to date, lacks studies on the biological effects of this species, particularly with regard to cytotoxicity and induction of DNA damage. The aim of the present study was to assess in vitro (in hepatic HTC cells) ethanolic extracts of the roots and leaves of C. mollis for cytotoxicity, genotoxicity, and induction of apoptosis. For these evaluations the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay, comet assay, micronucleus test with cytokinesis block, and an in situ test for detection of apoptotic cells with acridine orange staining were used. The results showed that the extract obtained from the roots of C. mollis is more cytotoxic than that obtained from the leaves and that the reduction in cell viability observed in the MTT assay was a result, at least in part, from the induction of apoptosis. Both extracts induced DNA damage at a concentration of 20 microg/mL in the comet assay, but no genotoxicity was detected with any of the treatments carried out in the micronucleus test.

Protective effects of beta-glucan extracted from barley against benzo[a]pyrene-induced DNA damage in hepatic cell HepG2.

The aim of the present study was to assess the genotoxic and antigenotoxic effect of beta-glucan (BG) extracted from barley. The genotoxicity of BG was tested in the single-cell gel electrophoresis assays (SCGE)/HepG2 test system. Moreover, the protective effects of BG against the genotoxicity of B[a]P were studied to delineate its mechanism of antigenotoxicity using four different treatment protocols - pre-treatment, simultaneous simple, simultaneous with pre-incubation, and post-treatment. The results showed that the compound itself was devoid of mutagenic activity at the three lower concentrations studied (1, 5, and 25microg/mL); however, genotoxic and cytotoxic effects were seen at 100 and 200microg/mL, respectively. In combination experiments with B[a]P, pronounced inhibition of DNA migration in the SCGE assay was observed in the two simultaneous treatments, and a smaller reduction was observed in the two other treatments. Thus, the data suggest that BG acts through binding to the genotoxic compound or capturing free radicals produced during its activation. However, the protective effects observed with pre-treatment and post-treatment suggest that the BG may be modulating cell metabolism.

beta-Glucans in promoting health: prevention against mutation and cancer.

The polysaccharides beta-glucans occur as a principal component of the cellular walls. Some microorganisms, such as yeast and mushrooms, and also cereals such as oats and barley, are of economic interest because they contain large amounts of beta-glucans. These substances stimulate the immune system, modulating humoral and cellular immunity, and thereby have beneficial effect in fighting infections (bacterial, viral, fungal and parasitic). beta-Glucans also exhibit hypocholesterolemic and anticoagulant properties. Recently, they have been demonstrated to be anti-cytotoxic, antimutagenic and anti-tumorogenic, making them promising candidate as pharmacological promoters of health.

First genotoxicity study of Paraná river water from Argentina using cells from the clam Corbicula fluminea (Veneroida Corbiculidae) and Chinese hamster (Cricetulus griseus Rodentia, Cricetidae) K1 cells in the comet assay

High concentrations of xenobiotics from urban and industrial wastes have contributed to the contamination of many aquatic environments. We used the comet assay to evaluate the genotoxic potential of water collected from the River Paraná, which receives a great deal of waste, at three points (Puerto Piray, Eldorado and Montecarlo) in the Misiones Province of Argentina. The in vivo comet assay used 40 freshwater clams (Corbicula fluminea) while the in vitro comet assay used Chinese hamster (Cricetulus griseus) K1 cell (CHO-K1) cultures with the mutagen ethyl methanesulfonate (EMS) as the positive control and phosphate buffered saline (PBS) as the negative control. Both assays showed statistically significant differences between the three sampling sites in relation to the negative control, the results of this preliminary study indicating that at these three sites water from the Paraná River presents genotoxic potential.

Respuesta hepática en ratas tratadas con hexaclorobenceno utilizando diferentes fuentes de carbohidratos en la dieta / Hepatic response in rats treated with hexachlorobenzene fed differing in the carbohydrate source

Ratas Wistar machos de peso 280 g, recibieron dosis total de dos gramos de hexaclorobenceno (HCB), administrado en lña dieta semipurificada normoproteica isocalórica (18 por ciento de caseína, 68,5 por ciento de hidrato de carbono, que contenía almidón o sacarosa), durante 8 semanas. La capacidad del HCB de estimular la actividad del sistemamicrosómico hepático fue evaluada in vivo mediante el test de parálisis de las patas traseras utilizando zoxazolamina (i.p.). Fueron evaluados el peso del hñígado y su composición bioquímica en proteínas, lípidos, ADN y ARN. Las muestras de hígado fueron estudiadas histologicamente. El tratamiento con HCB no modificó el patrón de ingestión de alimentos en ambos grups tratados con sacarosa o almidón. Los animales con sacarosa mostraronb menor ingestión de alimento. Sin embargo, el desarrollo y el peso corporal fueron semejantes en ambos grupos al final del experimento. Los animales tratados con HCB presentaron, independientemente de la fuente de carbohidratos de la dieta, reducción del tiempo de parálisis de las patas traseras por la zoxazolamina, aumento de peso del hígado y de los contenidos de proteínas y lípidos, junto a una menor concentración hepática de ADN, Histológicamente se observó hipertrofia de hepatocitos centrolobulillares y cúmulo graso en hepatocitos de la zona periportal. los resultados de este estudio mostraron que, bajo los parámetros estudiados, las ratas expuestas al HCB presentaron inducción del sistema microsómico hepático. Esta inducción fue acompañada por un agrandamiento de hepatocitos centrolobulillares y aumento de peso del hígado y de su contenido en proteínas.

Respuesta hepática en ratas tratadas con hexaclorobenceno utilizando diferentes fuentes de carbohidratos en la dieta / Hepatic response in rats treated with hexachlorobenzene fed differing in the carbohydrate source

Ratas Wistar machos de peso 280 g, recibieron dosis total de dos gramos de hexaclorobenceno (HCB), administrado en lña dieta semipurificada normoproteica isocalórica (18 por ciento de caseína, 68,5 por ciento de hidrato de carbono, que contenía almidón o sacarosa), durante 8 semanas. La capacidad del HCB de estimular la actividad del sistemamicrosómico hepático fue evaluada in vivo mediante el test de parálisis de las patas traseras utilizando zoxazolamina (i.p.). Fueron evaluados el peso del hñígado y su composición bioquímica en proteínas, lípidos, ADN y ARN. Las muestras de hígado fueron estudiadas histologicamente. El tratamiento con HCB no modificó el patrón de ingestión de alimentos en ambos grups tratados con sacarosa o almidón. Los animales con sacarosa mostraronb menor ingestión de alimento. Sin embargo, el desarrollo y el peso corporal fueron semejantes en ambos grupos al final del experimento. Los animales tratados con HCB presentaron, independientemente de la fuente de carbohidratos de la dieta, reducción del tiempo de parálisis de las patas traseras por la zoxazolamina, aumento de peso del hígado y de los contenidos de proteínas y lípidos, junto a una menor concentración hepática de ADN, Histológicamente se observó hipertrofia de hepatocitos centrolobulillares y cúmulo graso en hepatocitos de la zona periportal. los resultados de este estudio mostraron que, bajo los parámetros estudiados, las ratas expuestas al HCB presentaron inducción del sistema microsómico hepático. Esta inducción fue acompañada por un agrandamiento de hepatocitos centrolobulillares y aumento de peso del hígado y de su contenido en proteínas. (AU)