Mahmoud Abudayyak

Investigation on the toxic potential of Tribulus terrestris in vitro

Abstract Context: Tribulus terrestris L. (Zygophyllaceae) has been commonly used to energize, vitalize, and improve sexual function and physical performance in men. Objective: This study investigates the potential cytotoxic and genotoxic, and endocrine disrupting activities of T. terrestris in vitro. Materials and methods: The whole T. terrestris plant was extracted with water, methanol, and chloroform. The genotoxic potential of T. terrestris extracts at 3–2400 µg/mL was assessed by Comet assay in a rat kidney cell line (NRK-52E) and by Ames assay in Salmonella typhimurium TA98 and TA100 strains. Endocrine disrupting effects of the extracts at concentrations of 0.22–25 000 µg/mL were assessed by YES/YAS assay in Saccharomyces cerevisiae. Cytotoxic activity of the extracts was determined by the MTT test in NRK-52E cells. The different exposure times were used for four tests (3–48 h). Results: The methanol extract of T. terrestris IC50 value was 160 µg/mL. The other extracts did not show cytotoxic effects. In the Comet and Ames genotoxicity assays, none of the extracts possessed genotoxic activities at concentrations of 0–2400 µg/mL. Only the water extract of T. terrestris induced frame shift mutations after metabolic activation. The water extract also showed estrogenic activity by YES/YAS assay in S. cerevisiae at concentrations ≥27 µg/mL (≥2.6-fold), while the other T. terrestris extracts had anti-estrogenic properties. Conclusion: Tribulus terrestris had estrogenic and genotoxic activities. The study was useful in determining its toxicological effects and the precautions regarding consumption.

Nickel oxide nanoparticles are highly toxic to SH-SY5Y neuronal cells

&NA; Nickel oxide nanoparticles (NiO‐NPs) are used in many industrial sectors including printing inks, ceramics and catalysts, and electrical and electronics industry because of their magnetic and optical properties. However, there has been still a serious lack of information about their toxicity at the cellular and molecular levels on nervous system. For that, we aimed to investigate the in vitro toxic potentials of NiO‐NPs in neuronal (SH‐SY5Y) cells. The particle characterisation, cellular uptake and morphological changes were determined using Transmission Electron Microscopy, dynamic light scattering and Inductively Coupled Plasma‐Mass Spectrometry. Then, the cytotoxicity was evaluated by MTT and neutral red uptake assays, the genotoxicity by comet assay, the oxidative potentials by the determination of malondialdehyde, 8‐hydroxy deoxyguanosine, protein carbonyl, and glutathione levels with Enzyme‐Linked Immune Sorbent Assays, and the apoptotic potentials by Annexin V‐FITC apoptosis detection assay with propidium iodide. According to the results, it was observed that NiO‐NPs (15.0 nm ± 4.2–38.1 nm); (i) were taken up by the cells in concentration dependent manner, (ii) caused 50% inhibition in cell viability at ≥229.34 &mgr;g/mL, (iii) induced some morphological changes, (iv) induced dose‐dependent DNA damage (3.2–11.0 fold) and apoptosis (80–99%), (v) significantly induced oxidative damage. In conclusion, our results support the hypothesis that NiO‐NPs affect human health especially neuronal system negatively and should raise the concern about the safety associated with their applications in consumer products.

Effects of bentazone on lipid peroxidation and antioxidant systems in human erythrocytesin vitro

Abstract Bentazone, a benzothiadiazole herbicide, is widely used for a variety of crops including cereals, maize, peas, rice and soy beans. The concern for human health is stil very high because bentazone is continuously monitored in environment and several studies to evaluate its potential carcinogenic effects when chronic and high doses were administered to animals. We aimed to investigate the possible effects of bentazone on lipid peroxidation, levels of glutathione and activities of antioxidant enzymes in human erythrocytes in vitro. For that, erythrocyte were incubated with bentazone in different concentrations (0–50 nM) at 37 °C for 1 hr. Bentazone showed significant increase in the levels of malondialdehyde (MDA) at the highest concentration in erythrocytes as an index of lipid peroxidation. Besides, alterations in the levels of reduced glutathione (GSH) and activities of glutathione peroxidase (GSH-Px) were observed while the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GSH-Rd) were unchanged. In conclusion, findings from this study indicate that in vitro toxicity of bentazone may be associated with oxidative stress and this work warrants further in vivo investigations.

Effects of prochloraz on DNA damage, lipid peroxidation and antioxidant system in vitro.

Abstract Prochloraz is a broad-spectrum contact imidazol fungicide used against several diseases in wheat, barley and oleaginous plants but also for treatment of flower production. Although prochloraz has endocrine disrupting and hepatocarcinogenic effects, there is lack of data on toxic effects of prochloraz. Therefore, we aimed to investigate the DNA damage effects of prochloraz in NRK-52E cells by using Ames and Comet assay. By using a standard alkaline Comet assay procedure, there was no DNA damage observed after 24 h prochloraz exposure. It also showed that prochloraz caused neither base-pair substitution nor frame shift mutations by using TA98, TA100 strains, respectively, with/without metabolic activation in Ames assay. Both Comet and Ames assays, the exposure concentrations were 12.5, 25, 50 and 100 µM. IC50 value of prochloraz was determined as 110.76 µM in NRK-52E cells by MTT cytotoxicity test. Also, we evaluated possible effects of prochloraz on lipid peroxidation, reduced glutathione (GSH), oxidized glutathione (GSSG) and antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GSH-Rd) in NRK-52E cells at 1–50 µM concentrations. Prochloraz induced lipid peroxidation and altered glutathione contents and antioxidant enzyme activities in NRK-52E cells. Our results indicated that prochloraz showed no evidence of mutagenicity and DNA damage; however, some alterations were observed on lipid peroxidation and antioxidant systems in prochloraz treatment.

In vitro evaluation of cobalt oxide nanoparticle-induced toxicity:

Cobalt oxide (Co3O4) nanoparticles have applications in nanomedicine and nanotechnology; therefore, any possible adverse effects require thorough investigation. The present study investigated the effects of Co3O4 nanoparticles on four different cell lines: liver, HepG2 hepatocellular carcinoma cells; lung, A549 lung carcinoma cells; gastrointestinal, Caco-2 colorectal adenocarcinoma cells; and nervous system, SH-SY5Y neuroblastoma cells. A difference was observed in cell sensitivity toward Co3O4 nanoparticles. Co3O4 nanoparticles were taken up by all the cell types. However, no cell death was observed in HepG2, Caco-2, or SH-SY5Y cells; only A549 cells showed cytotoxicity at relatively high exposure concentrations. Co3O4 nanoparticles did not induce DNA damage or apoptosis in the cell lines tested except in A549. Interestingly, Co3O4 nanoparticles induced cellular oxidative damage in all cell types except Caco-2, resulting in increased malondialdehyde and 8-hydroxydeoxyguanosine levels and decreased glutathione levels. According to our results, it could be indicated that high concentrations of Co3O4 nanoparticles affected the pulmonary system but were unlikely to affect the liver, nervous system, or gastrointestinal system. Co3O4 nanoparticles might be safely used for industrial, commercial, and nanomedical applications if dose rates are adjusted depending on the route of exposure. However, further in vivo and in vitro studies are required to confirm the safety of Co3O4 nanoparticles.

In Vitro Evaluation of the Toxicity of Cobalt Ferrite Nanoparticles in Kidney Cell

Objectives: The remarkable properties of hard magnetic cobalt ferrite nanoparticles (CoFe2O4-NPs) and their physicochemical stability lead to various applications in different industrial and medical fields. Although CoFe2O4-NPs have been reported to cause toxic effects, there is a serious lack of information concerning their effects on the kidneys. In this study, it was aimed to investigate the toxic effects of CoFe2O4-NPs on NRK-52E kidney cells. Materials and Methods: The particle characterisation and cellular uptake were determined using transmission electron microscopy, dynamic light scattering and inductively coupled plasma-mass spectrometry. Then, the cytotoxicity was evaluated by MTT and neutral red uptake assays, the genotoxicity by comet assay, and the apoptotic potentials by Annexin V-FITC apoptosis detection assay with propidium iodide. Results: After 24 h exposure to CoFe2O4-NPs (39±17 nm), it was observed they did not affect the cell viability at concentration ranging from 100 to 1000 µg/mL, but significantly induced DNA damage at concentration ≤100 µg/mL. No apoptotic or necrotic effect was observed in the exposed cells. Conclusion: According to the results obtained, CoFe2O4-NPs are promising for safe use in various applications. However, further in vivo studies are needed to fully understand their mechanisms of action.

ASSESSMENT OF CELLULAR RESPONSES IN KIDNEY CELLS EXPOSED TO COBALT OXIDE NANOPARTICLES

Cobalt oxide (Co3O4) nanoparticles have been extensively used in various industrial and medical applications due to their special optical, magnetic, and electrical activity features. However, there is a lack of information about their toxicity and adverse effects on human health, especially concerning the kidney, which is considered to be a secondary target organ. We investigated the toxic potentials of Co3O4 nanoparticles on NRK-52E kidney epithelial cells by in vitro assays. Co3O4 nanoparticles were taken up by the kidney cells, and caused a decrease in cell viability, by significantly inducing apoptosis/ necrosis at 100 μg/mL. However, no significant DNA damage was observed. Co3O4 nanoparticles induced cellular toxicity in kidney cells. These results should raise concern about the safety of Co3O4 nanoparticles in their various applications. Further studies are needed to elucidate their toxic mechanism.