Subchronic exposure to fenpyroximate causes multiorgan toxicity in Wistar rats by disrupting lipid profile, inducing oxidative stress and DNA damage.

BACKGROUND: Fenpyroximate (FEN) is an acaricide that inhibits the complex I of the mitochondrial respiratory chain in mites. Data concerning mammalian toxicity of this acaricide are limited; thus the aim of this work was to explore FEN toxicity on Wistar rats, particularly on cardiac, pulmonary, and splenic tissues and in bone marrow cells. METHODS: rats were treated orally with FEN at 1, 2, 4, and 8 mg/Kg bw for 28 days. After treatment, we analyzed lipid profile, oxidative stress and DNA damage in rat tissues. RESULTS: FEN exposure increased creatinine phosphokinase (CPK) and lactate dehydrogenase (LDH) activities, elevated total cholesterol (T-CHOL), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) concentrations, while decreasing high-density lipoprotein cholesterol (HDL-C). It inhibited acetylcholinesterase (AChE) activity, enhanced lipid peroxidation, protein oxidation, and modulated antioxidant enzymes activities (superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase). Comet assay indicated that FEN induced a dose-dependent DNA damage, contrasting with the micronucleus test showing no micronuclei formation. Nonetheless, FEN exhibited cytotoxicity to bone marrow cells, as evidenced by a reduction in the number of immature erythrocytes among total cells. CONCLUSION: FEN appears to carry out its genotoxic and cytotoxic activities most likely through an indirect pathway that involves oxidative stress.

Genotoxic damage and apoptosis in rat glioma (F98) cell line following exposure to bromuconazole.

Bromuconazole, a fungicide from the triazole family, is widely used to protect the crop from various fungal contaminations to increase product quality and productivity. Although the massive use of bromuconazole poses a serious risk to human health, the exact mechanism of bromuconazole toxicity, especially on brain support cells, called glia cells, remains unclear so far. This study aimed to determine the mechanism of cytotoxicity and genotoxicity of bromuconazole via inspection of apoptotic death in rat glioma (F98) cells. We observed that bromuconazole treatment caused concentration-dependent cell death with an IC50 of 60 µM, and disruption of the cytoskeleton was observed via immunocytochemical analysis. Further, bromuconazole inhibits cell proliferation, it arrests the cell cycle in the G0/G1 phase and so inhibits DNA synthesis. Genotoxic analysis showed that bromuconazole exposition causes DNA fragmentation (comet assay) and nuclear condensation (DAPI staining). Apoptotic cell death was confirmed through: positive Annexin-V/FITC-PI dyes, p53 and Bax overexpression, Bcl2 repression, an increase in Bax/BCL-2 ratios of the mRNA, mitochondrial membrane depolarization, and an increase of caspase-3 activity. All these results demonstrate that bromuconazole exerts its cytotoxic and genotoxic effects through apoptotic cell death, which could implicate mitochondria.

Low grade intravascular hemolysis associates with peripheral nerve injury in type 2 diabetes.

Type 2 diabetes (T2D) induces hyperglycemia, alters hemoglobin (Hb), red blood cell (RBC) deformability and impairs hemorheology. The question remains whether RBC breakdown and intravascular hemolysis (IVH) occur in T2D patients. We characterized RBC-degradation products and vesiculation in a case-control study of 109 T2D patients and 65 control subjects. We quantified heme-related absorbance by spectrophotometry and circulating extracellular vesicles (EV) by flow cytometry and electron microscopy. Heme-related absorbance was increased in T2D vs. control plasma (+57%) and further elevated in obese T2D plasma (+27%). However, large CD235a+ EV were not increased in T2D plasma. EV from T2D plasma, or shed by isolated T2D RBC, were notably smaller in diameter (-27%) and carried heme-related absorbance. In T2D plasma, higher heme-related absorbance (+30%) was associated to peripheral sensory neuropathy, and no other vascular complication. In vitro, T2D RBC-derived EV triggered endothelial stress and thrombin activation in a phosphatidylserine- and heme-dependent fashion. We concluded that T2D was associated with low-grade IVH. Plasma absorbance may constitute a novel biomarker of peripheral neuropathy in T2D, while flow cytometry focusing on large EV may be maladapted to characterize RBC EV in T2D. Moreover, therapeutics limiting IVH or neutralizing RBC breakdown products might bolster vasculoprotection in T2D.

Bromuconazole fungicide induces cell cycle arrest and apoptotic cell death in cultured human colon carcinoma cells (HCT116) via oxidative stress process.

BACKGROUND: Bromuconazole, a fungicide belonging to the triazole family, is a plant protection product used to control, repel or destroy fungi that may develop on crops. We investigated the pro-apoptotic effect of bromuconazole and the role of oxidative stress in the death mechanism induced by this fungicide in this study. METHODS: The human colon HCT116 cell line was treated with Bromuconazole (IC50/4, IC50/2, and IC50) for 24 h. Cells were collected and analysed for biomarkers of apoptotic cell death and oxidative stress as well as for the assessment of genotoxic damage. RESULTS: Our study showed that bromuconazole caused a concentration-dependent increase in cell mortality with an IC50 of 180 µM. Bromuconazole induced cell cycle arrest in the G0/G1 phase and DNA synthesis inhibition. The Comet assay showed that bromuconazole caused DNA damage in a concentration-dependent manner. Bromuconazole-induced apoptosis was observed by, Annexin-V/FITC-PI and BET/AO staining, by mitochondrial membrane depolarisation, and by increased caspase-3 activity. In addition, bromuconazole induced a significant increase in ROS and lipid peroxidation levels and a disruption in SOD and CAT activities. N-acetylcysteine (NAC) strongly prevents cytotoxic and genotoxic damage caused by bromuconazole. CONCLUSION: Bromuconazole toxicity was through the oxidative stress process, which causes DNA damage and mitochondrial dysfunction, leading to cell cycle arrest and apoptotic death of HCT116 cells.

Bromuconazole exposure induced cell cycle arrest in the G0/G1 in HCT116 cells.Bromuconazole caused DNA synthesis inhibition and degradation.Bromuconazole-induced Annexin-V/FITC-PI and BET/AO positive staining, increased caspase-3 activity and MMP.Bromuconazole enhances ROS, MDA levels and disruption of CAT and SOD activities.

Evaluation of hepatotoxicity and nephrotoxicity induced by fenpyroximate in subchronic-orally exposed Wistar rats.

BACKGROUNDS: Fenpyroximate (FEN) is an acaricide that inhibits the complex I of the mitochondrial respiratory chain. The aim of this work was to explore the hepatotoxic and nephrotoxic effects of FEN on Wistar rats. METHODS: The study involved five groups: a control group and four groups treated with FEN at 1, 2, 4, and 8 mg/Kg bw for 28 consecutive days. Histological examination and biochemical analysis of hepatic and renal biomarkers were performed. The malondialdehyde (MDA), protein carbonyl levels, and antioxidant enzymes activities were measured. Comet assay was conducted to explore FEN genotoxicity. RESULTS: FEN induced a disturbance of the hepatic and renal functions as evidenced by an increase in AST, ALT, ALP, creatinine, and uric acid levels and histopathological modifications in the two examined tissues. FEN increased hepatic and renal lipid peroxidation and protein oxidation. The activities of liver and kidney SOD, CAT, GPX, and GST are increased significantly in FEN-treated rats at doses of 2 and 4 mg/kg bw. However, with the dose of 8 mg/kg bw of FEN, these activities are decreased. Moreover, FEN increased DNA damage in a dose-dependent manner. CONCLUSION: FEN was hepatotoxic and nephrotoxic very likely through induction of oxidative stress.

Brain injury, genotoxic damage and oxidative stress induced by Bromuconazole in male Wistar rats and in SH-SY5Y cell line.

BACKGROUND: Bromuconazole is a widely used triazole against various fungi disease. It's employment provokes harmful effects on the environment and human health. In the present study, we explored bromuconazole toxic effects in both rat brain tissue and SH-SY5Y cell line. METHODS: Male Wistar rats were administrated orally with Bromuconazole (NOEL/4, NOEL o and NOEL ×2) daily for consecutive 28 days. In addition, neuronal SH-SY5Y cell line was used. The rat brains and SH-SY5Y cells were collected and analysed for AChE activity, oxidative stress biomarkers, genotoxicity and histopathological alterations. RESULTS: Our results showed that rat exposure to bromuconazole at doses corresponding to NOEL/4, NOEL and NOEL ×2 caused brain histopathological alteration and decrease in acetylcholine esterase (AChE) activity. In SH-SY5Y cell line, bromuconazole strongly induced cell mortality with an IC50 about 250 µM. Bromuconazole induced also DNA damage as assessed by comet assay in both rat brain tissue and SH-SY5Y cell. Moreover, bromuconazole increased ROS production, malondialdehyde (MDA) and protein carbonyl (PC) levels and enhanced the enzymatic activities of catalase (CAT), superoxide dismutase (SOD), Glutathione-S-transferase (GST) and peroxidase (GPx) in the two studied systems. CONCLUSION: Therefore, we can deduce that bromuconazole-caused neurotoxicity may be related to oxidative statue disturbance.HIGHLIGHTSBromuconzole causes oxidative stress in the brain tissue of male Wistar rats.Bromuconazole enhances MDA, PC levels and induces DNA damage in rat brain.Bromuconazole provokes disturbance of the neuronal antioxidant system.Bromuconazole induces histopathological alterations in rat brain.Bromuconazole exposure induced cytotoxic effects and DNA damage in SH-SY5Y cells.Bromuconazole exposure induced oxidative stress in SH-SY5Ycells.

Fenpyroximate induced cytotoxicity and genotoxicity in Wistar rat brain and in human neuroblastoma (SH-SY5Y) cells: Involvement of oxidative stress and apoptosis.

Fenpyroximate (FEN) is an acaricide used in agriculture / horticulture to control spider mites and leafhoppers. It inhibits the transport of mitochondrial electrons at the level of NADH-coenzyme Q oxidoreductase (complex I). Despite the implication of inhibition of mitochondrial complex I in neurotoxicity, especially in neurodegenerative diseases, data concerning FEN neurotoxicity remain limited. Thus, the present study was designed to investigate the toxic effect of FEN on rat brain tissue and on human neuroblastoma cells (SH-SY5Y). Rat exposure to FEN at three different doses (4.8, 9.6 and 48 mg / Kg bw) for 28 consecutive days resulted in histopathological modifications in brain tissue and a significant decrease in acetylcholinesterase activity. Further, FEN significantly enhanced lipid peroxidation and protein oxidation in rat brain and disturbed activities of antioxidant enzymes (SOD, CAT, GPx, and GST). Besides, FEN was found to induce DNA damage in a significant and dose-dependent manner in rat brain as assessed by the comet assay. To better understand FEN neurotoxic effect, we monitored our study on SH-SY5Y cells. We confirm our data found in rat brain tissue. In fact, FEN induced cell mortality in a concentration dependent manner. It over-produced intracellular ROS and lipid peroxidation and enhanced SOD and CAT activities. FEN was also found to induce DNA damage in SH-SY5Y cells. Moreover, FEN induced a loss of mitochondrial membrane potential, which confirms FEN mitochondrial impairing activity. Acridine Orange-Bromure Etidium (AO-BE) cell staining indicated that FEN enhanced the percentage of apoptotic cells in a concentration dependent manner. Further, pretreatment with a general caspases inhibitor (ZVAD-FMK), reduced significantly the FEN induced cell mortality. We also shown that FEN increased caspase 3 activity. These findings suggested, for the first time, the possibility of the involvement of mitochondrial pathway in FEN-induced cell apoptosis.

Bromuconazole caused genotoxicity and hepatic and renal damage via oxidative stress process in Wistar rats.

Bromuconazole is a triazole pesticide used to protect vegetables and fruits against diverse fungi pathologies. However, its utilization may be accompanied by diverse tissue injuries. In this study, we evaluated the biochemical and histopathological modifications, and we analyzed genotoxic and oxidative stress, in the aim to examine bromuconazole effects in the liver and kidney. We subdivided animals into four groups, each one contains six adult male Wistar rats. Untreated rats received daily a corn oil (vehicle) orally. Three oral bromuconazole doses were tested (1, 5, and 10 % of LD50) daily for 28 days. Bromuconazole increased the plasma activities of alkaline phosphatase, lactate dehydrogenase, and transaminases. It also increased the plasma levels of creatinine and uric acid. Histopathological check showed that bromuconazole caused organ damage. This study makes known that bromuconazole caused conspicuous DNA damage either in hepatic or kidney tissues, with a significant increase in the levels of malondialdehyde and protein carbonyl followed by an enhancement in catalase and superoxide dismutase enzymatic activities, and these increases are in a dose-dependent manner. In other side, we found that Glutathione-S-transferase and peroxidase activities raised. Our outcomes highlight that bromuconazole exposure induced genotoxic damage and organ damage which may be caused by the disturbances of oxidative stress statue in the liver and kidney.

New familial cases of karyomegalic interstitial nephritis with mutations in the FAN1 gene.

BACKGROUND: Karyomegalic interstitial nephritis (KIN) is a rare disease entity first described by Burry in 1974. The term KIN was introduced by Mihatsch et al. in 1979. KIN is characterized by chronic tubulointerstitial nephritis associated with enlarged tubular epithelial cell nuclei, which leads to a progressive decline of renal function. The prevalence of this disease is less than 1% of all biopsies, and its pathogenesis is unclear. KIN results from mutations in FAN1 (FANCD2/FANCI-Associated Nuclease 1), a gene involved in the DNA damage response pathway, particularly in the kidney. In this study, we report two Tunisian consanguineous families with KIN caused by mutations in the FAN1 gene. METHODS: Direct sequencing of the coding regions and flanking intronic sequences of the FAN1 gene was performed in three affected members. Three prediction programs (Polyphen-2 software, SIFT, and MutationTaster) were used to predict the functional effect of the detected variations. RESULTS: Two causative frameshift variants in the FAN1 gene were identified in each family: The previously described frameshift mutation c.2616delA (p.Asp873ThrfsTer17) and a novel mutation c.2603delT (p.Leu868ArgfsTer22) classified as "pathogenic" according to the American College of Medical Genetics and Genomics (ACMG) guidelines. CONCLUSION: To our best knowledge, this is the first Tunisian study involving familial cases of KIN with mutations in the FAN1 gene. We hypothesize that these findings can expand the mutational spectrum of KIN and provide valuable information on the genetic cause of KIN.

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.

Effects of Gamma Irradiation on Ochratoxin A Stability and Cytotoxicity in Methanolic Solutions and Potential Application in Tunisian Millet Samples.

Gamma irradiation is a useful technology for degrading mycotoxins. The purpose of this study was to investigate the effect of irradiation on ochratoxin A (OTA) stability under different conditions. OTA was irradiated in methanolic solution and on millet flour at doses of 2 and 4 kGy. Residual OTA concentrations and possible degradation products in irradiated samples were analyzed by high-performance liquid chromatography with fluorescence detection and liquid chromatography coupled to mass spectrometry. The extent of in vitro cytotoxicity of OTA to HepG2 cells, with and without irradiation treatment, was assessed with an MTT assay. OTA was more sensitive to gamma radiation on Tunisian millet flour than in methanolic solutions. After irradiation of naturally contaminated millet flour, the OTA concentration was significantly reduced by 48 and 62% at a dose of 2 and 4 kGy, respectively. However, in the methanolic solution, OTA at concentrations of 1 and 5 µg mL-1 was relatively stable even at a dose of 4 kGy, with no degradation products detected in the chemical analysis. Analytical results were confirmed by cell culture assays. The remaining cytotoxicity (MTT assay) of OTA following irradiation was not significantly affected compared with the controls. These findings indicate that gamma irradiation could offer a solution for OTA decontamination in the postharvest processing chain of millet flour. However, the associated toxicological hazard of decontaminated food matrices needs more investigation.

The novel cationic cell-penetrating peptide PEP-NJSM is highly active against Staphylococcus epidermidis biofilm.

A cationic cell-penetrating peptide PEP-NJSM was identified in human virus proteomes by a screening of charge clusters in protein sequences generating Cell-Penetrating Peptides (CPP). PEP-NJSM was selectively active against Gram-positive Staphylococcus epidermidis as antibacterial agent with MIC value of 128 µM compared to the Gram-negative Pseudomonas aeruginosa strain with MIC value exceeded 512 µM. The selected peptide exhibited an important anti-biofilm activity even at sub-MIC levels. PEP-NJSM could prevent biofilm formation and increase the mortality of cells inside mature S. epidermidis biofilm. The results demonstrated that PEP-NJSM presented an important anti-adherent activity. It showed a S. epidermidis inhibition of biofilm formation >84% at a concentration of 256 µM (2 X MIC) and remained active even at a concentration of 4 µM with 32% of inhibition. The eradication of the established biofilm was observed at a concentration of 256 µM with 55.7% of biofilm eradication. The peptide was active against mature biofilm even at low concentration of 0.5 µM with approximately 22.9% of eradication. PEP-NJSM exhibited low hemolytic activity and cytotoxicity against mammalian cells. Our results demonstrate that PEP-NJSM could have a potential role in the treatment of diseases related to Staphylococcus epidermidis infection.

Beneficial effects of mycophenolate mofetil on cardiotoxicity induced by tacrolimus in wistar rats.

The immunosuppressive drug tacrolimus (TAC) is used clinically to reduce the rejection rate in transplant patients. TAC has contributed to an increased prevalence of cardiovascular disease in patients receiving solid organ transplantation. Mycophenolate mofetil (MMF), a potent inhibitor of de novo purine synthesis, is known to prevent ongoing rejection in combination with TAC. In the present study, we investigated the antioxidant and antigenotoxic effect of MMF on TAC-induced cardiotoxicity in rats. Oral administration of TAC at 2.4, 24, and 60 mg/kg b.w. corresponding, respectively, to 1, 10, and 25% of LD50 for 24 h caused cardiac toxicity in a dose-dependant manner. TAC increased significantly DNA damage level in hearts of treated rats. Furthermore, it increased malondialdehyde (MDA) and protein carbonyl (PC) levels and decreased catalase (CAT) and superoxide dismutase (SOD) activities. The oral administration of MMF at 50 mg/kg b.w. simultaneously with TAC at 60 mg/kg b.w. proved a significant cardiac protection by decreasing DNA damage, MDA, and PC levels, and by increasing the antioxidant activities of CAT and SOD. Thus, our study showed, for the first time, the protective effect of MMF against cardiac toxicity induced by TAC. This protective effect was mediated via an antioxidant process.

Combination of tacrolimus and mycophenolate mofetil induces oxidative stress and genotoxicity in spleen and bone marrow of Wistar rats.

Tacrolimus (TAC) and mycophenolate mofetil (MMF) are common immunosuppressive drugs used to avoid immunological rejection of transplanted organs. The risk of developing cancer is the most critical complication in organ transplant recipients undergoing immunosuppressive therapy. This study aims to explore the cytotoxic and genotoxic effects of TAC and MMF alone or combined orally administrated on spleen and bone marrow of Wistar rats. Our results showed that TAC (2.4; 24 and 60mg/kg) and MMF (5; 50 and 125mg/kg) induced a genotoxic effect on rat bone marrow. Moreover, the co-treatment with the TAC/MMF (2.4/5mg/kg b.w.; 2.4/50mg/kg b.w. and 60/50mg/kg b.w.) produce a genotoxicity as measured by micronuclei (MN) frequencies, chromosomal aberrations (CA) rates and DNA damage levels. Furthermore, the TAC and MMF-treated animals developed oxidative stress in spleen, indicated by a significant increase of malondialdehyde (MDA), protein oxidation and decrease of anti-oxidant enzymes levels such as catalase (CAT) and superoxide dismutase (SOD). This damage was associated with an increase of DNA fragmentation. Co-treatment with TAC/MMF synergistically induced markers of oxidative stress in rat splenic tissue. In conclusion, TAC/MMF associated induction in oxidative stress plays a role in the splenic and bone marrow toxicity and enhances the different endpoints of genotoxicity, suggesting its mutagenic action in vivo.

Protective effect of mycophenolate mofetil against nephrotoxicity and hepatotoxicity induced by tacrolimus in Wistar rats

Tacrolimus (TAC), a calcineurin inhibitor (CNI), is clinically used as an immunosuppressive agent in the transplant recipient; however, the use of TAC is greatly limited by its nephrotoxicity and hepatotoxicity. Mycophenolate mofetil (MMF), an inhibitor of the purine synthesis, has been used in combination with many immunosuppressive drugs such as TAC. The association TAC/MMF was used in organ transplantation to increase the efficiency and reduce acute rejection rates, but the effects of MMF on TAC-induced kidney and liver injuries are still not well investigated. The aims of this study are to explore whether MMF co-administration with TAC has a renoprotective and hepatoprotective effect against TAC-induced renal and hepatic injuries and to check the implication of oxidative stress in the MMF’s possible protective effect. Our results showed that MMF (at 50 mg kg−1 body weight (b.w.)) restored creatinine, in addition to increased AST and ALT levels by TAC (at 60 mg kg−1 b.w.). Furthermore, MMF decreased DNA damage induced by TAC in the kidney and liver of rats as assessed by comet assay. This renoprotective and hepatoprotective effect of MMF was associated with an antioxidant effect. In fact, MMF co-treatment with TAC decreased oxidative damage induced by TAC. It reduced malondialdehyde (MDA) and protein carbonyl (PC) levels as well as catalase and superoxide dismutase (SOD) activities. We conclude that the co-administration MMF with TAC protect liver and kidney against TAC toxicity via an antioxidant process (AU)

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The mycotoxin zearalenone enhances cell proliferation, colony formation and promotes cell migration in the human colon carcinoma cell line HCT116.

Zearalenone (ZEN) and Aflatoxin B1 (AFB1) are fungal secondary metabolites produced by Fusarium and Aspergillus genera, respectively. These mycotoxins are found world-wide as corn and wheat contaminants. AFB1 is probably the most toxic and carcinogenic mycotoxin. It has been demonstrated to be mutagenic, genotoxic, and hepatocarcinogenic. ZEN is a non-steroidal estrogenic mycotoxin that displays hepatotoxicity, immunotoxicity and genotoxicity. Its mutagenic and carcinogenic properties have so far remained controversial and questionable. Using the colon carcinoma cell line HCT116, we will show here that ZEN, at low concentrations, enhances cell proliferation, increases colony formation and fastens cell migration after wound healing. The highest effect of ZEN was observed at a concentration 10 times lower as compared to AFB1. Our findings suggest thus that this mycotoxin exhibits carcinogenesis-like properties in HCT116 cells.

Ochratoxin A and T-2 Toxin Induce Clonogenicity and Cell Migration in Human Colon Carcinoma and Fetal Lung Fibroblast Cell Lines.

T-2 toxin and Ochratoxin A (OTA) are toxic secondary metabolites produced by various fungi, and together they contaminate feedstuffs worldwide. T-2 toxin and OTA may exert carcinogenic action in rodent. Despite the various in vivo experiments, carcinogenicity of these two mycotoxins has not yet been proven for human. In this current study, we proposed to investigate, in Human colon carcinoma cells and fetal lung fibroblast-like cells transfected with MYC, the effect of T-2 toxin and OTA on cell clonogenicity and cell migration. Results of the present investigation showed that T2-toxin as well as OTA has an important clonogenic effect in all cell lines, suggesting that these mycotoxins could promote the transcription of c-myc gene. Furthermore, T-2 toxin and OTA enhanced the migration effect of HCT116 cells at very low concentrations, proposing that these mycotoxins may exhibit carcinogenesis-like properties in the studied cells.

Protective effect of mycophenolate mofetil against nephrotoxicity and hepatotoxicity induced by tacrolimus in Wistar rats.

Tacrolimus (TAC), a calcineurin inhibitor (CNI), is clinically used as an immunosuppressive agent in the transplant recipient; however, the use of TAC is greatly limited by its nephrotoxicity and hepatotoxicity. Mycophenolate mofetil (MMF), an inhibitor of the purine synthesis, has been used in combination with many immunosuppressive drugs such as TAC. The association TAC/MMF was used in organ transplantation to increase the efficiency and reduce acute rejection rates, but the effects of MMF on TAC-induced kidney and liver injuries are still not well investigated. The aims of this study are to explore whether MMF co-administration with TAC has a renoprotective and hepatoprotective effect against TAC-induced renal and hepatic injuries and to check the implication of oxidative stress in the MMF's possible protective effect. Our results showed that MMF (at 50 mg kg(-1) body weight (b.w.)) restored creatinine, in addition to increased AST and ALT levels by TAC (at 60 mg kg(-1) b.w.). Furthermore, MMF decreased DNA damage induced by TAC in the kidney and liver of rats as assessed by comet assay. This renoprotective and hepatoprotective effect of MMF was associated with an antioxidant effect. In fact, MMF co-treatment with TAC decreased oxidative damage induced by TAC. It reduced malondialdehyde (MDA) and protein carbonyl (PC) levels as well as catalase and superoxide dismutase (SOD) activities. We conclude that the co-administration MMF with TAC protect liver and kidney against TAC toxicity via an antioxidant process.

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.

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.