Cytotoxicity and chromosomal aberrations induced by acrylamide in V79 cells: role of glutathione modulators

Morin protects against acrylamide-induced neurotoxicity in rats: an investigation into different signal pathways

The presented study investigates the effects of morin against toxicity induced by acrylamide (ACR) in the brains of Sprague Dawley rats. In this study, neurotoxicity was induced by orally administering 38.27 mg/kg/b.w ACR to rats through gastric gavage for 10 days. Morin was administered at the same time and at different doses (50 and 100 mg/kg/b.w) with ACR. Biochemical and Western blot analyses showed that ACR increased malondialdehyde (MDA), p38α mitogen-activated protein kinase (p38α MAPK), nuclear factor kappa-B (NF-κB), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), p53, caspase-3, bcl-2 associated X protein (Bax), Beclin-1, light chain 3A (LC3A), and light chain 3B (LC3B) levels and decreased those of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), b-cell lymphoma-2 (Bcl-2), mammalian target of rapamycin (mTOR), phosphoinositide 3-kinase (PI3K), and protein kinase B (Akt) in brain tissue and therefore induced neurotoxicity by causing oxidative stress, inflammation, apoptosis, and autophagy. On the other hand, it was determined that morin positively affected the levels of these markers by displaying antioxidant, anti-inflammatory, anti-apoptotic, and anti-autophagic properties and had a protective effect on ACR-induced neurotoxicity. As a result, morin is an effective substance against brain damage caused by ACR, yet further studies are needed to use it effectively.

Protective effect of seabuckthorn berry juice against acrylamide-induced oxidative damage in rats

Acrylamide (AA), classified as a probable carcinogen, can be neurotoxic, genotoxic, and can damage DNA. This study explored the ability of seabuckthorn berries juice (SBJ) to alleviate AA-induced toxic injury in rats. Twenty-four adult male Sprague-Dawley (SD) rats were randomly divided into four groups: control group, AA group (40 mg/kg), AA + SBJ (40 mg/kg AA and 5 mL/kg SBJ), and AA + vitamin C (VC) group (positive control group, 40 mg/kg AA and 100 mg/kg VC). At the end of the experiment, rats in AA group showed a marked decrease in the rate of weight gain, hind extremity abduction, and ataxia. Obvious anomalies were seen in plasma biochemical parameters (P < 0.05), and different degrees of injury were observed upon histological examination of five tissues (hippocampus, cerebellum, liver, small intestine, and kidney). Compared to the control group, levels of superoxide dismutase, catalase, and glutathione were significantly decreased, while malondialdehyde was elevated (P < 0.05). SBJ treatment reduced the abnormal of behavior, hematological index, antioxidant enzyme, and tissue damage caused by AA in rats. PRACTICAL APPLICATION: Seabuckthorn berries are wild berries rich in vitamin C and polyphenols, which have good antioxidant properties. In this experiment, SBJ has a significant alleviating effect on AA-induced oxidative damage in rats. Therefore, we speculate that SBJ may relieve the oxidative damage caused by diet or other forms of AA exposure in the general population. At the same time, this experiment also provides new ideas for alleviating AA-induced in vivo toxicity.

A multiple endpoint approach reveals potential in vitro anticancer properties of thymoquinone in human renal carcinoma cells

Thymoquinone (TQ) is a monoterpene isolated from the oil of Nigella sativa seeds. The aim of this work was to evaluate the cytotoxic effects induced by TQ and its impact on the migration and invasion potential of 786-O human renal cancer cells. These cells were exposed to TQ (1-100 μM) for 24 and 48 h and cell viability assessed using the Crystal Violet and MTS assays. TQ treatment clearly decreased cell viability in a concentration- and time-dependent manner. TQ exposure moderately increased intracellular ROS levels and co-incubation with reduced glutathione markedly increased cell viability. Moreover, the effect of TQ in the cell cycle distribution was evaluated using flow cytometry, and an increase in the sub-G1 population was observed, especially at 30 μM, along with an increase in the % of apoptotic cells. TQ did not show genotoxic effects at a non-cytotoxic concentration (1.0 μM). At this concentration level, TQ significantly decreased the collective migration of 786-O cells, whereas it had no effect in chemotactic migration. TQ also decreased the invasiveness potential of 786-O cells, as evaluated by the transwell invasion assay. Overall, these results suggest that TQ presents an anticancer potential in the context of renal cancer, warranting further investigation.

Effects of acrylamide on oxidant/antioxidant parameters and CYP2E1 expression in rat pancreatic endocrine cells

Oxidative stress is one of the principle mechanism of acrylamide-induced toxicity. Acrylamide is metabolized by cytochrome P450 2E1 (CYP2E1) to glycidamide or by direct conjugation with glutathione. Bearing in mind that up to now the effects of acrylamide on oxidative stress status and CYP2E1 level in endocrine pancreas have not been studied we performed qualitative and quantitative immunohistochemical evaluation of inducible nitric oxide synthase (iNOS), superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), catalase (CAT) and CYP2E1 expression in islets of Langerhans of rats subchronically treated with 25 or 50mg/kg bw of acrylamide. Since the majority of cells (>80%) in rodent islets are beta cells, in parallel studies, we employed the Rin-5F beta cell line to examine effects of acrylamide on redox status and the activity of CAT, SOD and glutathione-S-transferase (GST), their gene expression, and CYP2E1, NF-E2 p45-related factor 2 (Nrf2) and iNOS expression. Immunohistochemically stained pancreatic sections revealed that acrylamide induced increase of iNOS and decrease of CYP2E1 protein expression, while expression of antioxidant enzymes was not significantly affected by acrylamide in islets of Langerhans. Analysis of Mallory-Azan stained pancreatic sections revealed increased diameter of blood vessels lumen in pancreatic islets of acrylamide-treated rats. Increase in the GST activity, lipid peroxidation and nitrite level, and decrease in GSH content, CAT and SOD activities was observed in acrylamide-exposed Rin-5F cells. Level of mRNA was increased for iNOS, SOD1 and SOD2, and decreased for GSTP1, Nrf2 and CYP2E1 in acrylamide-treated Rin-5F cells. This is the first report of the effects of acrylamide on oxidant/antioxidant parameters and CYP2E1 expression in pancreatic endocrine cells.

Acrylamide-derived cytotoxic, anti-proliferative, and apoptotic effects on A549 cells

BACKGROUND

Acrylamide is a very common compound even reaching up to our daily foods. It has been studied in a wealth of cell lines on which it proved to have various toxic effects. Among these cell lines, human lung adenocarcinoma cell line (A549) is one of that on which acrylamide's toxicity has not been studied well yet.

AIM

We intended to determine the half maximal inhibitory concentration (IC₅₀) dose of acrylamide and to investigate its cytotoxic, anti-proliferative and apoptotic effects on A549 cells.

METHODS

We determined the IC₅₀ dose by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Then, the mode of cell death was evaluated by flow cytometry using Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Next, we performed transmission electron microscopy (TEM) and confocal microscopy analyses for morphological alterations and apoptotic indices.

RESULTS

According to the MTT assay results, A549 cell viability decreases proportionally with increasing acrylamide concentrations and IC₅₀ for A549 was 4.6 mM for 24 h. Annexin-V FITC/PI assay results indicated that acrylamide induces apoptosis in 64% of the A549 cells. TEM and confocal microscopy analyses showed nuclear condensations, fragmentations, cytoskeleton laceration, and membrane blebbing, which are morphological characteristics of apoptosis.

CONCLUSION

Our research suggests that acrylamide causes cytotoxic, anti-proliferative, and apoptotic effects on A549 cells at 4.6 mM IC₅₀ dose in 24 h.

The chemoprotection of a blueberry anthocyanin extract against the acrylamide-induced oxidative stress in mitochondria: unequivocal evidence in mice liver

The mitochondrial mechanism of Acrylamide-induced oxidative stress.

Protection of cyanidin-3-glucoside against oxidative stress induced by acrylamide in human MDA-MB-231 cells

Acrylamide (AA) occurs in many cooked starchy foods and has caused widespread concern as a possible carcinogen. In the present study, we investigate the intervention of AA toxicity in MDA-MB-231 cells pretreated with cyanidin-3-glucoside (Cy-3-glu). Compared to the cells treated with AA, Cy-3-glu significantly inhibited AA-induced cytotoxicity, reduced reactive oxygen species (ROS) generation, recovered glutathione (GSH) depletion and decreased the activities of glutathione peroxidase (GPx) and glutathione S-transferase (GST). Moreover, the expression of GPx1, GSTP1 and gamma-glutamyl cysteine synthase (γ-GCS) were enhanced, and cytochrome P450 2E1 (CYP2E1) expression was inhibited by the pretreatment of Cy-3-glu. Cy-3-glu presents the protective role against oxidative stress induced by AA in MDA-MB-231 cells.

Naturally contaminated shellfish samples: quantification of diarrhetic shellfish poisoning toxins in unhydrolysed and hydrolysed extracts and cytotoxicity assessment

Contamination of shellfish from the Portuguese coast with diarrhetic shellfish poisoning (DSP) toxins is a recurrent event, with most of the commercial bivalves contaminated with high percentages of esters of okadaic acid (OA) and dinophysistoxin-2 (DTX2). This report describes the quantification of DSP toxins in unhydrolysed and hydrolysed extracts of several cockle and mussel samples naturally contaminated and the evaluation of their cytotoxicity profiles in V79 cells. The quantification of the acyl esters in the shellfish samples involved the cleavage of the ester bond through alkaline hydrolysis and the release of the parent toxins OA and DTX2. Unhydrolysed and hydrolysed extracts were then analyzed by liquid chromatography (LC) coupled with mass spectrometry (MS) for the detection and quantification of DSP toxins. The cytotoxicity of the analysed extracts was evaluated using the MTT reduction assay and compared with the cytotoxicity presented by different concentrations of OA standard (1-100 nM). OA exhibited marked cytotoxic effects and decreased cell viability in a dose dependent mode, with an IC₅₀ of 27 nM. The cytotoxicity pattern of unhydrolysed extracts was clearly dependent on the concentration of free toxins. Moreover, the cytotoxicity of the esterified toxins present was revealed after their conversion into free toxins by alkaline hydrolysis. For the hydrolysed extracts of cockles and mussels, the cytotoxicity presented was mainly related to the concentration of OA and DTX2.

Protective effect of l-carnitine against acrylamide-induced DNA damage in somatic and germ cells of mice

Recent findings of acrylamide (AA) in many common foods have sparked renewed interest in assessing human health hazards. AA was evaluated by the International Agency for Research on Cancer as probably carcinogenic to humans. For this reason, the aim of this study is to evaluate the potential genotoxic effect of AA using chromosomal aberration analysis and micronucleus (MN) test in mouse bone-marrow cells and morphological sperm abnormalities. The result of the present work indicated that treatment with a single dose of 10, 20, or 30 mg/kg b.wt. of AA for 24 h and the repeated dose of 10 mg/kg b.wt. for 1and 2 weeks induced a statistically significant increase in the percentage of chromosomal aberrations and micronuclei in bone- marrow cells. These percentages reduced significantly in all groups treated with AA and the protective agent l-carnitine. Also the results indicated that the dose 10, 20 and 30 mg/kg b.wt. of AA induced a statistically significant percentage of morphological sperm abnormalities compared with the control group. Such effect reached its maximum (7.24 ± 0.61) with the highest tested dose which reduced to (4.02 ± 0.58) in the group treated with the same dose of AA and l-carnitine. In conclusion, the results confirm the protective role of LC against the mutagenicity of AA.

Protective role of ortho-substituted Mn(III) N-alkylpyridylporphyrins against the oxidative injury induced by tert-butylhydroperoxide

The present work addresses the role of two ortho-substituted Mn(III) N-alkylpyridylporphyrins, alkyl being ethyl in MnTE-2-PyP(5+) and n-hexyl in MnTnHex-2-PyP(5+), on the protection against the oxidant tert-butylhydroperoxide (TBHP). Their protective role was studied in V79 cells using endpoints of cell viability (MTT and crystal violet assays), intracellular O(2)*- generation (dihydroethidium assay) and glutathione status (DTNB and monochlorobimane assays). MnPs per se did not show cytotoxicity (up to 25 microM, 24 h). The exposure to TBHP resulted in a significant decrease in cell viability and in an increase in the intracellular O(2)(*-) levels. Also, TBHP depleted total and reduced glutathione and increased GSSG. The two MnPs counteracted remarkably the effects of TBHP. Even at low concentrations, both MnPs were protective in terms of cell viability and abrogated the intracellular O(2)(*-) increase in a significant way. Also, they augmented markedly the total and reduced glutathione contents in TBHP-treated cells, highlighting the multiple mechanisms of protection of these SOD mimics, which at least in part may be ascribed to their electron-donating ability.