Triflumuron induces cytotoxic effects on hepatic and renal human cell lines.

Insect growth regulator insecticides are a new class of pesticides, commonly used around the world to control insect damages. Among those compounds, we focused our interest on triflumuron (TFM), which is less toxic than other conventional insecticides. However, not much is known about its toxic effects on mammalian systems. Therefore, our study aimed toward evaluating the cytotoxic and genotoxic effects of TFM using two different cell lines, the human renal embryonic cells (HEK 293) and hepatocytes (Hep G2). We showed, according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, that TFM reduced significantly the cell viability and increased the reactive oxygen species generation, malondialdehyde levels, and mitochondrial membrane potential in both cell lines. The antioxidant system was disturbed as assessed by the increased activities in both catalase and superoxide dismutase. We demonstrated also, that TFM is an inductor of DNA damages quantified by the comet assay. Moreover, we showed an overexpression of proapoptotic Bax and a decrease in antiapoptotic Bcl-2 expression. As a conclusion, we demonstrate that the liver presents the major target organ to TFM, in which the cytotoxicity and the genotoxic effects were significantly higher in hepatic cells than in renal cells and by consequence its uses must be controlled.

Influence of bifentrin, a pyrethriod pesticide, on human colorectal HCT-116 cells attributed to alterations in oxidative stress involving mitochondrial apoptotic processes.

The widespread use of pesticides is beneficial for food production; however, there are numerous adverse consequences reported in the ecosystem and humans associated with exposure to these contaminants. The pyrethriod bifenthrin (BIF) is utilized for (1) maintenance, growth, and storage of agricultural products; (2) control of internal and external parasites of farm animals; and (3) eradication of insects threatening public health. Numerous data are available regarding environmental and ecological impact of pyrethriods on the central and peripheral nervous systems; however few studies focused on non-target tissues especially in humans. Therefore, the aim of this investigation was to determine the potential cytotoxic effects of BIF on a non-target tissue using human colorectal HCT-116 cells as a model. Data demonstrated that BIF reduced cell viability and disrupted mitochondrial functions which were accompanied by increased reactive oxygen species (ROS) levels indicating the presence of oxidative stress. BIF produced a significant elevation in levels of malondialdehyde (MDA) supporting the role of oxidative stress in pesticide-mediated toxicity. Concomitantly, a fall of mitochondrial transmembrane potential (Δψ), consequently producing perturbation of fluidity as well as excitability of cellular membranes was noted. Our results also indicated that BIF induced a rise in DNA damage as evidenced by the comet assay. An increase in mitogen-activated protein kinases (MAPKs), JNK (N-terminal Kinase), p38, and ERK (extracellular-signal-regulated kinase) suggested an apoptotic effect. Data thus indicated that BIF-induced cytotoxicity in human colorectal HCT-116 cells was associated with oxidative stress, mitochondrial dysfunction, and apoptosis.

Tebuconazole induces ROS-dependent cardiac cell toxicity by activating DNA damage and mitochondrial apoptotic pathway.

Tebuconazole (TEB) is a common triazole fungicide that is widely used throughout the world in agriculture applications. We previously reported that TEB induces cardiac toxicity in rats. The aim of this study was to investigate the underlying mechanism of the toxicity induced by TEB in cardiac cells. TEB induced dose-dependent cell death in H9c2 cardiomyoblasts and in adult rat ventricular myocytes (ARVM). The comet assay and western blot analysis showed a concentration-dependent increase in DNA damage and in p53 and p21 protein levels 24 h after TEB treatment. Our findings also showed that TEB triggered the mitochondrial pathway of apoptosis as evidenced by a loss of mitochondrial transmembrane potential (ΔΨm), an increase in Bax/Bcl-2 ratio, an activation of caspase-9 and caspase-3, a cleavage of poly (ADP-ribose) polymerase (PARP) and an increase in the proportion of cells in the sub-G1 phase. In addition, TEB promoted ROS production in cardiac cells and consequently increased the amounts of MDA, the end product of lipid peroxidation. Treatment of cardiomyocytes with the ROS scavenger N-acetylcysteine reduced TEB-induced DNA damage and activation of the mitochondrial pathway of apoptosis. These results indicate that the genotoxic and cytotoxic effects of TEB are mediated through a ROS-dependent pathway in cardiac cells.

Triflumuron induces genotoxicity in both mice bone marrow cells and human Colon cancer cell line.

Triflumuron (TFM) is an insect growth regulator (IGR), an insecticide commonly used over the world. It is known for its several toxic manifestations, such as reprotoxicity, immunotoxicity and hematotoxicity, which could affect public health. However, studies that reveal its toxic effects on mammalians are limited. To reach this purpose, our study aimed to elucidate the eventual genotoxic effects of TFM in mice bone marrow cells and in HCT 116 cells after a short term exposition. TFM was administered intraperitoneally to Balb/C male mice at doses of 250, 350 and 500 mg/kg bw for 24 h. Genotoxicity was monitored in bone marrow cells using the comet test, the micronucleus test and the chromosome aberration assay. Our results showed that TFM induced DNA damages in a dose-dependent manner. This genotoxicity was confirmed also in vitro on human intestinal cells HCT 116 using the comet test. It was then asked whether this genotoxicity induced by TFM could be due to an oxidative stress. Thus, we found that TFM significantly decreased HCT 116 cell viability. In addition, it induced the generation of reactive oxygen species (ROS) followed by lipid peroxidation as revealed by the increase in the malondialdehyde (MDA) levels. Similarly, the activation of the antioxidant enzymes (catalase and superoxide dismutase) was also observed. Our results indicated that, in our experimental conditions, TFM had a genotoxic effect on bone morrow cells and in HCT 116 cells. Moreover, we demonstrated that this genotoxicity passes through an oxidative stress.

Di (2-ethylhexyl) phthalate induces cytotoxicity in HEK-293 cell line, implication of the Nrf-2/HO-1 antioxidant pathway.

The di (2-ethylhexyl) phthalate (DEHP) is a plasticizer used in the polyvinyl chloride industry. Human exposure to this plasticizer is inevitable and contributes to several side effects. In this study, we examined whether DEHP induces apoptosis and oxidative stress in embryonic kidney cells (HEK-293) and whether the nuclear factor E2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) antioxidant pathway is involved in the pathogenesis of this process. We demonstrated that DEHP is cytotoxic to HEK-293 cells. It causes oxidative damage through the generation of free radicals, induces lipid peroxidation, and alters superoxide dismutase and catalase activities. Simultaneously, DEHP treatment decreases the expression and the protein level of Nrf-2 and HO-1. Inhibition of the Nrf-2/HO-1 pathway is related to the mitochondrial pathway of apoptosis. This apoptotic process is characterized by a loss of mitochondrial transmembrane potential (ΔΨm) and upregulation of the expression of caspase-3 mRNA as well as its protein level.

Acetamiprid, a neonicotinoid insecticide, induced cytotoxicity and genotoxicity in PC12 cells.

Neonicotinoids are a group of pesticides widely used in agriculture and at home. Among those pesticides, acetamiprid (ACM) is a broad-spectrum insecticide used for the protection of vegetables and fruits from pest. The extensive use of this pesticide had led to contamination of environment including soil, water, as well as food products. However, there are few informations regarding the molecular mechanism by which ACM exerts its cytotoxic and genotoxic effects. The aim of the present study was to investigate the toxic effects of ACM in PC12 cells. We demonstrated that ACM significantly decreased cell viability as assessed by the MTT assay. We also shown that ACM-induced reactive oxygen species (ROS) generation followed by lipid peroxidation as evidenced by an increase in the MDA levels. The increase in cell death was accompanied by a reduction in the mitochondrial membrane potential. Besides, pretreatment with Z-VAD-FMK, a general caspases inhibitor, significantly decreased the ACM-induced cell death. Our results also indicate that ACM induced a concentration-dependent increase in DNA damage as evident by the Comet assay. These data indicate that ACM produces cytotoxicity and DNA damage in mammalian cells. Highlights ACM is cytotoxic toward rat pheochromocytoma adrenal medulla cells (PC12). ACM induces ROS generation, lipid peroxidation, and DNA fragmentation. ACM induces caspase-dependent apoptosis in PC12 cells.

SIRT1 protects cardiac cells against apoptosis induced by zearalenone or its metabolites α- and ß-zearalenol through an autophagy-dependent pathway.

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by several species of Fusarium in cereals and agricultural products. The major ZEN metabolites are α-zearalenol (α-ZOL) and ß-zearalenol (ß-ZOL). In the present study, we investigated the underlying mechanism of the toxicity induced by ZEN, α-ZOL and ß-ZOL in cardiac cells (H9c2). We show that treatment with ZEN or its metabolites induces the activation of the mitochondrial pathway of apoptosis as characterized by an increase in ROS generation, a loss of mitochondrial transmembrane potential (ΔΨm) and an activation of caspases. Besides, we demonstrate that these mycotoxins promote the activation of autophagy before the onset of apoptosis. Indeed, we observed that a short-time (6h) treatment with ZEN, α-ZOL or ß-ZOL, increased the level of Beclin-1 and LC3-II and induced the accumulation of the CytoID® autophagy detection probe. Moreover, the inhibition of autophagy by Chloroquine significantly increased cell death induced by ZEN, α-ZOL or ß-ZOL, suggesting that the activation of autophagy serves as a cardioprotective mechanism against these mycotoxins. In addition, we found that the inhibition (EX527) or the knockdown of SIRT1 (siRNA) significantly increased apoptosis induced by ZEN or its derivatives, whereas SIRT1 activation with RSV greatly prevents the cytotoxic effects of these mycotoxins. By contrast, when autophagy was inhibited by CQ, the activation of SIRT1 by RSV had no protection against the cardiotoxicity of ZEN or its metabolites, suggesting that SIRT1 protects cardiac cells by an autophagy-dependent pathway.

The potential effect of patulin on mice bearing melanoma cells: an anti-tumour or carcinogenic effect?

Mycotoxins are bioactive compounds that are noxious to human. Their effects on oncogenesis have been satisfactorily elucidated, and some of mycotoxins have been classified as carcinogenic to humans. Nevertheless, patulin (PAT) is considered by the International Agency of Research on Cancer as 'not carcinogenic to humans'. The present study was designed to understand the effect of this mycotoxin on melanoma cells (B16F10) by measuring cell proliferation and assessing the anti-tumour effect in vivo in Balb/c mice. Our results revealed that intraperitoneally administration of PAT for 20 days significantly induces tumour regression in B16F10 cell-implanted mice. This effect was evidenced by the activation of apoptosis which is supported by the increase in p53 and Bax expressions, the downregulation of the protein levels of Bcl2, and the increase in caspase-3 activity. Moreover, systemic toxicity analysis demonstrated that there is no potential toxicity following PAT treatment unlike untreated melanoma mice which suffer from anaemia, inflammation and liver dysfunction. Remarkably, this is the first published report demonstrating the therapeutic efficacy of PAT in vivo models.

Crocin and quercetin prevent PAT-induced apoptosis in mammalian cells: Involvement of ROS-mediated ER stress pathway.

Patulin (PAT) is a secondary metabolite produced by several species of the genera of Penicillium, Aspergillus, and Byssochlamys that can be found in rotting fruits, especially in apples and apple-based products. Exposure to this mycotoxin has been reported to induce intestinal and kidney injuries. The mechanism underlying such toxicity has been linked to the induction of apoptosis which occurred with reactive oxygen species production and endoplasmic reticulum (ER) stress induction. This study aimed to evaluate the effect of the two common dietary compounds Quercetin (QUER), a natural flavonoid, and Crocin (CRO), a natural carotenoid, on PAT-induced toxicity in human colon carcinoma (HCT116) and embryonic kidney cells (HEK293). We showed that antioxidant properties of QUER and CRO help to prevent ER stress activation and lipid peroxidation as evidenced by the reduction in GRP78 and GADD34 expressions and the decrease in malondialdehyde production. Furthermore, we demonstrated their ability to re-establish the loss of the mitochondrial membrane potential to inhibit caspase 3 activation and DNA fragmentation. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1851-1858, 2016.

The evaluate and compare the effects of the Tacrolimus and Sirolimus on the intestinal system using an intestinal cell culture model.

Tacrolimus (TAC) and Sirolimus (SRL) are produced by Streptomyces sp and effective immunosuppressive drugs commonly used in organ transplantation. Therefore, strategies for minimizing the toxicity of immunosuppressant molecules are our interest. This study was conducted to evaluate the interactive effects and the possible underlying mechanism of TAC and SRL on HCT116 cells. It was found that TAC and SRL alone inhibited cell viability. Also, it induced reactive oxygen species (ROS) formation, loss of mitochondrial membrane potential (Δψm), and able to increase DNA fragmentation in a concentration-dependent manner. The use of combined SRL and TAC showed a reservation in all toxicity observed with the two immunosuppressive drugs separately. Our result demonstrated that the mechanisms of TAC and SRL at high concentration are closely connected with oxidative stress. Furthermore, SRL at low concentration plays a protective effect against TAC (IC50) which induced cytotoxicity and genotoxicity. However, using the combination of the SRL/TAC at high concentrations (IC30) appears as an antagonist response.

Crocin Prevents Patulin-Induced Acute Toxicity in Cardiac Tissues via the Regulation of Oxidative Damage and Apoptosis.

Patulin (PAT) is a mycotoxin produced by several species of the genera of Penicillium, Aspergillus, and Byssochlamys principally by Penicillium expansum. This mycotoxin is suspected to affect several organs including kidney and liver. However, its toxic effect on heart remains unknown. The present study investigated for the first time the cardiotoxic effect of PAT in mice. We demonstrated that PAT increased creatinin phosphokinase (CPK) level, induced lipoperoxydation and protein oxidation, and triggered the antioxidant enzymes such as superoxide dismutase and catalase activities. We also demonstrated that acute administration of PAT triggers apoptosis via P53 overexpression and caspase 3 activation. We further investigated the antioxidant efficiency of crocin (CRO), a carotenoid pigment, against PAT-induced cardiotoxicity. We found that pretreatment with CRO prevents cardiac impairment by reducing CPK levels, restoring the redox statute and suppressing apoptosis. Collectively, our data provide new preventive effect of CRO toward PAT-induced cardiotoxicity in mice.

Dichlorvos-induced toxicity in HCT116 cells: involvement of oxidative stress and apoptosis.

Organophosphorous (OP) pesticides are widely used in the agriculture and home. Among those pesticides, Dichlorvos (DDVP) is a worldwide used insecticide for pest control. DDVP is commonly used as an insecticide for maintenance and growth of agricultural products, to control the internal and external parasites of farm animals, and to eradicate insects threatening the household, public health, and stored products. Although substantial information is available regarding the environmental and ecological impact of DDVP, not much is known in regard to its toxicity in the mammalian system. Therefore a study was conducted for the assessment of cytotoxic and genotoxic effects of DDVP in human colon carcinoma (HCT116) cell line. We demonstrated that DDVP significantly decreased cell viability as assessed by the MTT assay. The increase in cell death was accompanied by a reduction in the mitochondrial membrane potential. Besides, pretreatment with Z-VAD-FMK, a general caspases inhibitor, decreased significantly the DDVP-induced cell death. We also shown that DDVP induced reactive oxygen species (ROS) generation followed by lipid peroxidation as evidenced by an increase in the MDA levels. Our results also indicate that DDVP induced a concentration-dependent increase in DNA damage as evident by the comet assay. These data indicate that DDVP produces cytotoxicity and DNA damage in mammalian cells and should be used with caution.

Effects of Dichlorvos on cardiac cells: Toxicity and molecular mechanism of action.

In this study we aimed to understand the underlying mechanism of Dichlorvos-induced toxicity in cardiac cells. For this end, cells were treated by 170 µM of Dichlorvos (DDVP) (corresponding to the IC50) and molecular events were monitored by flow cytometry and western blotting. We have first demonstrated that cell exposure to DDVP for 24 h induced cell death by necroptosis. In fact, cell treatment with DDVP upregulated RIP1 expression and we have shown that chemical inhibition of RIP1 kinase activity by necrostatin-1 (Nec-1) greatly prevented from the induced cell death. Besides, we have demonstrated that, while there was no observed cell death following short exposure to DDVP (6 h), autophagy was enhanced, as proven by the increase in the level of both Beclin-1 and LC3-II and the accumulation of the CytoID® autophagy detection probe. Besides, when autophagy was inhibited by chloroquine (CQ) the percentage of necroptosis was significantly increased, suggesting that autophagy acts to protect cardiac cells against the toxicity induced by this pesticide. Concurrently, we have shown that the inhibition of the deacetylase sirtuin 1 (SIRT1) by EX527 or its knockdown by siRNA significantly increased DDVP-induced necroptosis, whereas when SIRT1 was activated by resveratrol (RSV) a significant decrease in DDVP-induced cell death was observed. In addition, we revealed that when the autophagy was inhibited by CQ, we can't reveal the protective effect of RSV anymore. Altogether, these results suggest that activation of SIRT1 protects cardiac cells from the toxicity of DDVP through an autophagy-dependent pathway.

Triazole fungicide tebuconazole induces apoptosis through ROS-mediated endoplasmic reticulum stress pathway.

Tebuconazole (TEB) is a common triazole fungicide that has been widely applied in the treatment of fungal diseases. It is reported that TEB could exert harmful effects on mammals' health. However, the molecular mechanism involved in TEB toxicity remain undefined. Our study aimed to investigate the mechanisms of TEB-induced toxicity in intestinal cells. We found that TEB stimulates apoptosis through the mitochondrial pathway. Additionally, TEB triggers endoplasmic reticulum (ER) stress as demonstrated by the activation of the three arms of unfolded protein response (UPR). The incubation with the chemical chaperone 4-phenylbutyrate (4-PBA) alleviated ER stress and reduced TEB-induced apoptosis, suggesting that ER stress plays an important role in mediating TEB-induced toxicity. Furthermore, inhibition of ROS by N-acetylcysteine (NAC) inhibited TEB-induced ER stress and apoptosis. Taken together, these findings suggest that TEB exerts its toxic effects in HCT116 cells by inducing apoptosis through ROS-mediated ER stress and mitochondrial apoptotic pathway.

Rosemary Tea Consumption Alters Peripheral Anxiety and Depression Biomarkers: A Pilot Study in Limited Healthy Volunteers.

Background: Rosmarinus officinalis L.is traditionally used as an infusion in the treatment of several diseases and in particular against neuropsychiatric disorders, such as anxiety and depression. It was established that rosemary extracts show an antidepressant effect on animal models. However, to the best of our knowledge, there is no scientific data that highlights the therapeutic effects of rosemary intake on human mental health.Aim: This study investigated whether rosemary tea consumption affects the plasma levels of anxiety and depression biomarkers in healthy volunteers.Methods: Twenty-two healthy volunteers aged between 20 and 50 years old consumed rosemary tea prepared from 5 g of dried rosemary in 100 mL boiled water once a day for 10 days. Plasma concentrations of Brain-Derived Neurotrophic Factor (BDNF), Interleukine-6 (IL-6), Interleukine-4 (IL-4), Tumor Necrosis Factor- alpha (TNF-α), Interferon-gamma (IFNϒ), and cortisol were measured by enzyme-linked immunosorbent assay using commercial ELISA kits (R&D systems) before rosemary consumption and at the end of the experiment.Results: Rosemary tea consumption significantly increased the concentration of BDNF([BDNF]D0 = 22363.86 ± 12987.66 pg/mL, [BDNF]D10 = 41803.64 ± 28109.19, p = 0.006) and TNF-α([TNF-α] D0 = 39.49 ± 14.44 pg/mL, [TNF-α] D10 = 56.24 ± 39.01, p = 0.016). However, a slight variation that was statistically non-significant in INFϒ, cortisol, IL-4, IL-6 levels and in the ratio IL-4/INFϒ was observed (p > 0.05).Conclusion: Our findings highlight the promising anxiolytic and/or antidepressant effects of rosemary tea consumption in healthy volunteers since it increases the level of the most reliable depression biomarker BDNF. However, more powerful studies with larger sample size, carefully-chosen target population and, an extended intervention period are required.

Influence of orthodontic appliance type on salivary parameters during treatment.

OBJECTIVES: To evaluate the effect of orthodontic appliances on physicochemical, biochemical, and oxidative stress changes in salivary parameters during treatment. MATERIALS AND METHODS: A cohort study was conducted with 112 healthy patients. Salivary samples were taken at baseline, 1 month, and 9 months after placement of the orthodontic appliances used in treatment. RESULTS: A statistically significant difference was observed in certain examined salivary parameters, including enzymes, electrolytes, and oxidative stress markers. CONCLUSIONS: The use of aligners had a lower prevalence of disturbing salivary parameters. Orthodontist must consider these changes to prevent the occurrence of white spot lesions.

Tebuconazole induced cardiotoxicity in male adult rat.

Tebuconazole is an effective systemic fungicide that belongs to the triazoles family. It has been widely used in both agricultural and medical sectors for the control of fungal diseases. Although TEB poses serious threats to mammals health, studies regarding its cardiotoxicity are very limited. Thus, we aimed to evaluate the effects of TEB on some biochemical parameters, the induction of apoptosis and DNA damage in the heart tissue. Male Wistar rats were treated with TEB at varied oral doses for 28 consecutive days. This study demonstrates that TEB decreased cardiac acetylcholinesterase, increased serum marker enzymes such as creatinine phosphokinase (CPK) and lactate dehydrogenase (LDH), and altered the lipid profile by increasing serum levels of total cholesterol (T-CHOL), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and reduced high-density lipoprotein cholesterol (HDL-C) levels. Furthermore, TEB increased levels of p53 and Bax/Bcl2 ratio, released the cytochrome c into the cytosol and activated caspase-9 and caspase-3. Besides, our results showed that TEB induced genotoxic effects. TEB induced DNA fragmentation and increased the frequency of micronucleated bone marrow cells. Moreover, TEB treatment developed fibrosis in the myocardium. Our results suggest that TEB exposure may affect myocardial cells normal functioning and triggers apoptosis.

Tissue oxidative stress induced by patulin and protective effect of crocin.

Patulin (PAT) is a secondary toxic metabolite produced principally by Penicillium expansum. This mycotoxin is known to be teratogenic, mutagenic, immunotoxic and neurotoxic, and it has been shown to cause damage in several organs in laboratory animals. This study focuses on the prevention of experimental murine PAT-induced nephrotoxicity and hepatotoxicity. We investigate the ability of a natural product, crocin (CRO), to counteract the toxic effects of PAT. Pre-treatment of mice with CRO prevented PAT-induced oxidative damage in both liver and kidney. CRO reduced lipid peroxidation, protein oxidation and restored redox status by regulating the endogenous antioxidant enzymatic system. These data corroborate and extend findings in PAT-induced nephrotoxicity and hepatotoxicity, and further suggest that preventive effect of CRO towards other forms of PAT toxicity, including neurotoxicity, may be warranted.

Crocin, the main active saffron constituent, mitigates dichlorvos-induced oxidative stress and apoptosis in HCT-116 cells.

The protective effects of Crocin (CRO), a carotenoid with wide spectrum of pharmacological effects, against the cytotoxicity and the apoptosis produced by exposure to Dichlorvos (DDVP) in HCT116 cells were investigated in this work. The cytotoxicity was monitored by cell viability, ROS generation, antioxidant enzymes activities, malondialdehyde (MDA) production and DNA fragmentation. The apoptosis was assessed through the measurement of the mitochondrial transmembrane potential (ΔΨm) and caspases activation. The results indicated that pretreatment of HCT116 cells with CRO, 2h prior to DDVP exposure, significantly increased the survival of cells, inhibited the ROS generation, modulated the activities of catalase (CAT) and superoxide dismutase (SOD) and reduced the MDA level. The reduction in mitochondrial membrane potential, DNA fragmentation and caspases activation were also inhibited by CRO. These findings suggest that CRO can protect HCT116 cells from DDVP-induced oxidative stress and apoptosis.