Levels of polychlorinated biphenyls and organochlorine pesticides in donkey milk: Correlation with the infection level by intestinal strongyles.

AIM: The study aimed at evaluating the concentration levels of organochlorine pollutants in donkey milk and their modulation on the intestinal strongyle infection. Risk evaluation for consumer health was also investigated. METHODS: We analyzed milk of grazing donkeys living in areas of Southern of Italy affected by organochlorine compounds environmental pollution and parasite infection. The presence of pollutants was assessed through summary statistics; regression analysis of intestinal strongyle on pollutant concentration was performed to investigate the relationship between the two variables. RESULTS: PCB concentrations (mainly non-dioxin-like (ndl)-PCBs) were higher than OCP ones. Mean values of ndl-PCBs across areas ranged from 93.13 to 263.64 ng g-1. In all sample units we detected the six indicator PCBs with the prevalence of the PCB 153, followed by the PCB 28 and the PCB 101. Among the dioxin-like (dl)-PCBs, non-ortho PCB 169, 77 and 126 were assessed in some milk samples; in all areas we detected the mono-ortho PCB 118 and PCB 105. Positive correlation between infection level and six indicator PCBs as well as between the former and HCB, on WW and LW, were observed (at least statistically significant at 5 percent). In some cases, Dl-PCB concentrations emerged as dangerous given the EU maximum residue limit for PCDD/Fs and dl-PCBs. CONCLUSION: Evidence supports the hypothesis of an immunosuppressive role of organochlorine pollutants; risk evaluation reveals the potential health impact of dl-PCB intake, particularly for major donkey milk consumers such as infants, children with cow milk and multiple food intolerance, and elders.

Thyroxine modulation of immune toxicity induced by mixture pesticides mancozeb and fipronil in mice.

AIM: The cross regulation between neuroendocrine system, particularly Hypothalamus-Pituitary-Thyroid (HPT) axis and immune system during embryonic/early neonatal developmental stages shapes the functional attribute of immune response throughout the life. Thus, disruption of immune system was anticipated on exposure to thyroid disrupting pesticides (TDPs) mancozeb (MCZ) and fipronil (FPN) during critical windows of early postnatal days (PND) development. MAIN METHODS: Mice were exposed to MCZ and FPN as individual (0.5% LD 50 each) and as mixtures (0.25% and 0.5% LD 50 each) from PND 31 (initiation phase of immune response) till PND 60 (Maturation phase). Thyroxine (T4) supplementation was given from PND 51 to PND 60. Assessment was done at PND 61 as well as at PND 91 (adults). KEY FINDINGS: Plasma level of thyroid hormones (T3 and T4) was reduced but pituitary hormone (TSH) increased till adulthood on exposure to mixture pesticides but not on individual exposure. Mixture pesticides also increased body weight gain and reduced survival rate in adults. Exposure of individual pesticides exert immunotoxicity but more pronounced immune suppression was observed in mixture pesticides exposed group as reflected in reduced relative weight and cellularity in spleen and thymus, reduced in vitro mitogenic (Con A/LPS) response of splenocytes and thymocytes (reduced proliferative index and increased apoptotic/necrotic death). T4 supplementation ameliorated thyroid disruptive and immunotoxic effect of pesticides. SIGNIFICANCE: The additive/synergistic toxicity as well as hypothyroidism induced by mixture pesticides has produced pronounced immune suppression that reflected till adulthood. Supplementation of T4 prevented thyroid axis disruption mediated immunosuppression.

Desarrollo y capacidad de remoción de los pesticidas atrazina, clorpirifós y endosulfán por parte de cepas de Aspergillus sección Flavi no toxigénicas / Development and removal ability of non-toxigenic Aspergillus section Flavi in presence of atrazine, chlorpyrifos and endosulfan

This study evaluated the in vitro effect of three concentrations of atrazine, chlorpyrifos and endosulfan on the growth parameters of four non-toxigenic Aspergillus section Flavi strains. The ability of the strains to remove these pesticides in a synthetic medium was also determined. Growth parameters were measured on soil extract solid medium supplied with 5,10 and 20mg/l of each pesticide, and conditioned to -0.70, -2.78, -7.06 and -10.0 water potential (MPa). Removal assays were performed in Czapek Doc medium (CZD) supplied with 20mg/l of each pesticide under optimal environmental conditions (-2.78 of MPa and 25 °C). The residual levels of each pesticide were detected by the reversed-phase HPLC/fluorescence detection system. The lag phases of the strains significantly decreased in the presence of the pesticides with respect to the control media. This result indicates a fast adaptation to the conditions assayed. Similarly, the mycelial growth rates in the different treatments increased depending on pesticide concentrations. Aspergillus oryzae AM 1 and AM 2 strains showed high percentages of atrazine degradation (above 90%), followed by endosulfan (56 and 76%) and chlorpyrifos (50 and 73%) after 30 days of incubation. A significant (p <0.001) correlation (r = 0.974) between removal percentages and growth rate was found. This study shows that non-toxigenic Aspergillus section Flavi strains from agricultural soils are able to effectively grow in the presence of high concentrations of atrazine, chlorpyrifos and endosulfan under a wide range of MPa conditions. Moreover, these strains have the ability to remove high levels of these pesticides in vitro in a short time.

En este estudio se evaluó los efectos in vitro de 3 concentraciones de atrazina, clorpirifós y endosulfán sobre los parámetros de crecimiento de 4 cepas no toxigénicas de Aspergillus sección Flavi. También se evaluó la capacidad de las cepas de remover los pesticidas. Los parámetros de crecimiento se ensayaron en medio agar extracto de suelo suplementado con 5, 10 y 20mg/l de cada pesticida y acondicionado a -0.70, -2.78, -7.06 y -10.0 de potencial de agua (MPa). Los ensayos de remoción se realizaron en medio Czapek Dox con 20mg/l de cada pesticida bajo condiciones óptimas de crecimiento (-2.78 de MPa y 25 °C). Los niveles residuales de atrazina, clorpirifós y endosulfán se detectaron en un sistema HPLC con detección por fluorescencia. La fase de latencia de las cepas disminuyó significantemente en presencia de los pesticidas, indicando una rápida adaptación a dichas condiciones. La velocidad de crecimiento se incrementó considerablemente dependiendo de la concentración de pesticida. Las cepas Aspergillus oryzae AM1 y AM2 mostraron porcentajes elevados de degradación de atrazina (aproximadamente el 90%), seguidos por endosulfán (56 y 76%) y clorpirifós (50 y 73%). Se observó una correlación (r = 0.974) significante (p <0.001) entre el porcentaje de pesticida removido y la velocidad de crecimiento. Este estudio muestra que cepas no-toxigénicas de Aspergillus sección Flavi aisladas de suelos agrícolas desarrollan eficientemente en presencia de altas concentraciones de atrazina, clorpirifós y endosulfán en un amplio rango de MPa. Además, presentan capacidad de remover in vitro altos niveles de pesticidas en corto tiempo.

Protective effect of lycopene against chemical and natural toxins: A review.

People are exposed to a number of environmental, occupational, and therapeutic toxic agents which may be natural or man made. These hazardous substances may manifest as direct side effects on the function of organs or indirectly induced alteration of gene expression, cancer-associated metabolic pathways, and/or alter homeostasis. Lycopene, as a one of the most potent antioxidant, is found in fruits and vegetables. High-intake of lycopene has been shown to be effective in decreasing the risk of both natural toxins including mycotoxins, bacterial toxins, and chemical toxins including heavy metals, pesticides as well as herbicides. Recently, there is growing attention in understanding the mechanisms of the phytochemicals and carotenoids as antioxidative, antiapoptotic, radical scavenging, and chelating agents and their roles in the modulation of inflammatory pathways. This review summarizes available data from several recent studies about lycopene and its role against chemical and natural toxicants. © 2018 BioFactors, 45(1):5-23, 2019.

Degradation of pesticides with RSDL® (reactive skin decontamination lotion kit) lotion: LC-MS investigation.

This study examined the degradation of organophosphate (OP) and carbamate pesticides using RSDL® (Reactive Skin Decontamination Lotion Kit) lotion. Degradation occurs from a nucleophilic substitution (SN) reaction between an ingredient in the RSDL lotion, potassium 2,3-butanedione monoximate (KBDO), with susceptible sites in the pesticides. Evaluation at several molar ratios of KBDO:test articles using liquid chromatography-mass spectrometry (LC-MS) techniques was performed. The OP test articles, parathion, paraoxon, parathion-methyl, paraoxon-methyl and chlorpyrifos were effectively degraded at molar ratios of four and above in less than 6min contact time. Malathion and malaoxon were similarly converted to inactive by-products at molar ratios as low as two in less than 4min. A minimum molar ratio of nine was found to be effective against the carbamate pesticide carbofuran. In the case of aldicarb, complete destruction was achieved at a molar ratio of fifteen and a reaction time of one hour. It is important to note that these studies are based on a direct liquid phase RSDL lotion reaction with the toxic chemicals without the added physical removal decontamination efficacy component provided by the sponge component of the RSDL kit. The RSDL kit is intended to be used to remove or neutralize chemical warfare agents (CWA) and T-2 toxin from the skin. In actual use, the majority of the CWA decontamination occurs through the combined action of the sponge in both removing the chemical from the skin, and in rapidly mixing the chemicals at a high molar ratio of KBDO:CWA within the pores of the sponge to enhance rapid neutralization of the chemical.

SAR study to find optimal cholinesterase reactivator against organophosphorous nerve agents and pesticides.

Irreversible inhibition of acetylcholinesterase (AChE) by organophosphates leads to many failures in living organism and ultimately in death. Organophosphorus compounds developed as nerve agents such as tabun, sarin, soman, VX and others belong to the most toxic chemical warfare agents and are one of the biggest threats to the modern civilization. Moreover, misuse of nerve agents together with organophosphorus pesticides (e.g. malathion, paraoxon, chlorpyrifos, etc.) which are annually implicated in millions of intoxications and hundreds of thousand deaths reminds us of insufficient protection against these compounds. Basic treatments for these intoxications are based on immediate administration of atropine and acetylcholinesterase reactivators which are currently represented by mono- or bis-pyridinium aldoximes. However, these antidotes are not sufficient to ensure 100 % treatment efficacy even they are administered immediately after intoxication, and in general, they possess several drawbacks. Herein, we have reviewed new efforts leading to the development of novel reactivators and proposition of new promising strategies to design novel and effective antidotes. Structure-activity relationships and biological activities of recently proposed acetylcholinesterase reactivators are discussed and summarized. Among further modifications of known oximes, the main attention has been paid to dual binding site ligands of AChE as the current mainstream strategy. We have also discussed new chemical entities as potential replacement of oxime functional group.

Probiotic lactobacilli: a potential prophylactic treatment for reducing pesticide absorption in humans and wildlife.

Numerous pesticides are used in agriculture, gardening, and wildlife-control. Despite their intended toxicity to pests, these compounds can also cause harm to wildlife and humans due to their ability to potentially bioaccumulate, leach into soils, and persist in the environment. Humans and animals are commonly exposed to these compounds through agricultural practices and consumption of contaminated foods and water. Pesticides can cause a range of adverse effects in humans ranging from minor irritation, to endocrine or nervous system disruption, cancer, or even death. A convenient and cost-effective method to reduce unavoidable pesticide absorption in humans and wildlife could be the use of probiotic lactobacilli. Lactobacillus is a genus of Gram-positive gut commensal bacteria used in the production of functional foods, such as yoghurt, cheese, sauerkraut and pickles, as well as silage for animal feed. Preliminary in vitro experiments suggested that lactobacilli are able to degrade some pesticides. Probiotic Lactobacillus rhamnosus GR-1-supplemented yoghurt reduced the bioaccumulation of mercury and arsenic in pregnant women and children. A similar study is warranted to test if this approach can reduce pesticide absorption in vivo, given that the lactobacilli can also attenuate reactive oxygen production, enhance gastrointestinal barrier function, reduce inflammation, and modulate host xenobiotic metabolism.

A comprehensive evaluation of the efficacy of leading oxime therapies in guinea pigs exposed to organophosphorus chemical warfare agents or pesticides.

The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection at the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl2, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 h post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman's method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes.

Protective effects of N-acetylcysteine on aluminum phosphide-induced oxidative stress in acute human poisoning.

OBJECTIVE: Aluminum phosphide is used as a fumigant. It produces phosphine gas (PH3). PH3 is a mitochondrial poison which inhibits cytochrome c oxidase, it leads to generation of reactive oxygen species; so one of the most important suggested mechanisms for its toxicity is induction of oxidative stress. In this regard, it could be proposed that a drug like N-acetylcysteine (NAC) as an antioxidant would improve the tolerance of aluminum phosphide-intoxicated cases. The objective of this study was to evaluate the protective effects of NAC on acute aluminum phosphide poisoning. METHODS: This was a prospective, randomized, controlled open-label trial. All patients received the same supportive treatments. NAC treatment group also received NAC. The blood thiobarbituric acid reactive substances as a marker of lipid peroxidation and total antioxidant capacity of plasma were analyzed. RESULTS: Mean ingested dose of aluminum phosphide in NAC treatment and control groups was 4.8 ± 0.9 g vs. 5.4 ± 3.3 g, respectively (p = 0.41). Significant increase in plasma malonyldialdehyde level in control group was observed (139 ± 28.2 vs. 149.6 ± 35.2 µmol/L, p = 0.02). NAC infusion in NAC treatment group significantly decreased malondialdehyde level (195.7 ± 67.4 vs. 174.6 ± 48.9 µmol/L, p = 0.03), duration of hospitalization (2.7 ± 1.8 days vs. 8.5 ± 8.2 days, p = 0.02), rate of intubation and ventilation (45.4% vs. 73.3%, p = 0.04). Mortality rate in NAC treatment and control groups were 36% and 60%, respectively with odds ratio 2.6 (0.7-10.1, 95% CI). CONCLUSION: NAC may have a therapeutic effect in acute aluminum phosphide poisoning.

Rotenone-induced apoptosis and role of calcium: a study on Neuro-2a cells.

Rotenone causes cytotoxicity in astrocytic cell culture by glial activation, which is linked to free radical generation. The present study is an investigation to explore whether rotenone could also cause cellular toxicity in mouse neuroblastoma cells (Neuro-2a) under treatment similar to astroglial cells. The effect of rotenone (0.1, 1, and 10 µM) on mitochondrial dehydrogenase enzyme activity by MTT reduction assay, PI uptake, total reactive oxygen species (ROS)/superoxide levels, nitrite levels, extent of DNA damage (by comet assay), and nuclear morphological alteration by Hoechst staining was studied. Caspase-3 and Ca⁺²/calmodulin-dependent protein kinase II (CaMKIIα) gene expression was determined to evaluate the apoptotic cell death and calcium kinase, respectively. Calcium level was estimated fluorometrically using fura-2A stain. Rotenone decreased mitochondrial dehydrogenase enzyme activity and generated ROS, superoxide, and nitrite. Rotenone treatment impaired cell intactness and nuclear morphology as depicted by PI uptake and chromosomal condensation of Neuro-2a cells, respectively. In addition, rotenone resulted in increased intracellular Ca⁺² level, caspase-3, and CaMKIIα expression. Furthermore, co-exposure of melatonin (300 µM), an antioxidant to cell culture, significantly suppressed the rotenone-induced decreased mitochondrial dehydrogenase enzyme activity, elevated ROS and RNS. However, melatonin was found ineffective to counteract rotenone-induced increased PI uptake, altered morphological changes, DNA damage, elevated Ca⁺², and increased expression of caspase-3 and CaMKIIα. The study indicates that intracellular calcium rather than oxidative stress is a major factor for rotenone-induced apoptosis in neuronal cells.

Design, evaluation and structure-activity relationship studies of the AChE reactivators against organophosphorus pesticides.

Organophosphate pesticides (OPPs; e.g. chlorpyrifos, diazinon, paraoxon) are a wide and heterogeneous group of organophosphorus compounds. Their biological activity of inhibiting acetylcholinesterase (AChE) or butyrylcholinesterase (BChE) ranks them as life endangering agents. The necessary treatment after OPP exposure involves the use of parasympatolytics (e.g. atropine), oxime reactivators (e.g. obidoxime), and anticonvulsive drugs (e.g. diazepam). Therefore, the reactivators of AChE are essential compounds in the treatment of OPP intoxications. Commercial AChE reactivators (e.g. pralidoxime, HI-6, obidoxime, trimedoxime, methoxime) were originally developed for other members of the organophosphate family, such as nerve agents (e.g. sarin, soman, tabun, VX). Pralidoxime, HI-6, and methoxime were found to be weak reactivators of OPP-inhibited AChE. Obidoxime and trimedoxime showed satisfactory reactivation against various OPPs with minor toxicity issues. During the last two decades, the treatment of OPP exposure has become more widely discussed because of growing agricultural production, industrialization, and harmful social issues (e.g. suicides). In this review is the summarized design, evaluation, and structure-activity relationship studies of recently produced AChE reactivators. Since pralidoxime, over 300 oximes have been produced or tested against OPP poisoning, and several novel compounds show very promising abilities as comparable (or higher) to commercial oximes. Some of these are highlighted for their further testing of OPP exposure and, additionally, the main structure-activity relationship of AChE reactivators against OPP is discussed.

Melatonin treatment prevents modulation of cell-mediated immune response induced by propoxur in rats.

The effect of melatonin, a major secretory product of the pineal gland, in attenuation of propoxur (2-isopropoxy phenyl N-methyl carbamate)-induced modulation of cell-mediated immune (CMI) response was studied in rats. Male Wistar albino rats were exposed to propoxur (a widely used pesticide) orally (10 mg/kg) and/or melatonin (10 mg/kg) orally for 4 weeks. CMI was measured by delayed-type hypersensitivity (DTH), leucocyte and macrophage migration inhibition (LMI and MMI) responses and estimation of cytokines TNF-alpha and IFN-gamma levels. Rats exposed to propoxur for 4 weeks showed significant decrease in DTH, LMI and MMI responses. Propoxur also suppressed TNF-alpha and IFN-gamma production significantly. Administration of melatonin alone caused a significant increase in DTH response. Although there were no changes in the LMI and MMI response, the cytokine levels were significantly increased, as compared to control. Co-administration of melatonin along with propoxur significantly nullified the effect of the pesticide on the CMI response, except DTH and reversed levels of cytokines to near control/normal values. Thus, melatonin treatment considerably attenuated immunomodulation caused by sub-chronic treatment of propoxur in experimental animals.

PolicosanolPlus and Neuroprevin ameliorate pesticide-mediated inhibition of neurite outgrowth and neurite degeneration.

BACKGROUND: Pesticide exposure is a recognized risk factor for neurodegenerative diseases. Recently, bifenthrin, a pyrethroid pesticide, was shown to inhibit the formation of neurites and cause neurite retraction, raising concern that these newer and less toxic pesticides may also contribute to neurodegenerative diseases. PolicosanolPlus and Neuroprevin are nutraceutical supplements which promote the survival of neurites in neuronal cell cultures. Here we determine if PolicosanolPlus and Neuroprevin can ameliorate the neurodegenerative effects of bifenthrin. MATERIAL/METHODS: PC12 cells were treated with NGF, bifenthrin, PolicosanolPlus and Neuroprevin in various combinations and the formation of neurites was assessed microscopically at times ranging from 12 to 72 hours post treatment. Bifenthrin was also withheld at the time of NGF, PolicosanolPlus and Neuroprevin treatment and added after neurite formed to assess neurite retraction. RESULTS: Bifenthrin (1 x 10(-6) M) inhibits neurite outgrowth, in the absence of cell death, by more than 50% at 12 hours and by more than 80% at 72 hours. With addition of PolicosanolPlus and/or Neuroprevin at the time of cell seeding, bifenthrin does not inhibit neurite outgrowth. Addition of bifenthrin to differentiated cells results in a retraction of 90% of neurites, while those with PolicosanolPlus and Neuroprevin show no significant retraction of neurites. CONCLUSIONS: The pesticide, bifenthrin, inhibits neurite formation and causes neurite retraction. PolicosanolPlus and Neuroprevin are nutraceutical supplements which ameliorate the effects of bifenthrin on neurite outgrowth and retraction. Dietary supplementation with PolicosanolPlus and Neuroprevin may protect against developmental and long-term neurodegenerative events that result from exposure to pesticides.

Pesticide-induced alteration in mice hepato-oxidative status and protective effects of black tea extract.

BACKGROUND: This study investigates the role of black tea extract in protection against oxidative damage induced in mice by a subacute oral dose of a combination of pesticides. METHODS: Liver damage markers like amino-acid transferases and alkaline phosphatase, oxidative damage markers indicating extent of lipid peroxidation, host antioxidant reserve indicators like reduced glutathione (GSH) and total thiol levels, GSH-dependent enzyme activities viz., glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) superoxide dismutase (SOD) and catalase (CAT) were measured by spectrophotometric techniques in four different groups namely (1) control, (2) black tea extract, (3) pesticide alone and (4) pretreatment with black tea extract followed by pesticide treatment. RESULTS: Following exposure to pesticides lipid peroxidation was increased compared to that in the control [0.50+/-0.083 (mean+/-S.E.) vs. 0.21+/-0.02 micromol/mg protein, p<0.001]. Moreover, levels of antioxidants like GSH and total thiol were also significantly decreased in comparison to control, e.g., GSH [5.16+/-0.78 vs. 6.96+/-1.35 micromol/mg protein, p<0.001], total thiol [19.3+/-2.74 vs. 26.15+/-2.8 micromol/mg protein, p<0.001]. In addition, the activities of antioxidant enzymes like GPx, GST, GR, SOD and catalase were also likewise diminished by oxidant damage. Treatment with aqueous black tea extract significantly protects the liver tissue from the oxidative damage and shifts the trend towards amelioration and replenishment of the antioxidant status. CONCLUSIONS: The active components present in natural extracts like that of black tea can be very effective in perhaps reducing the extent of injury and in overcoming oxidant damage caused by exposure to environmental agents like pesticides.

Glutatión S-transferasas en no-vertebrados y en mamíferos: su importancia en la detoxificación de insecticidas / The Glutathione S-transferases (GST) of non-vertebrate organisms and mammals

Las Glutatión S-transferasas (GST) de organismos no-vertebrados no han sido estudiadas con la misma intensidad que las de mamíferos. El interés en las GST en no-vertebrados radica en su importancia como protección bioquímica de los organismos expuestos a compuestos químicos ambientales. En efecto, se ha observado que niveles elevados de GST podrían estar asociados con la tolerancia a pesticidas. La intención de esta actualización es revisar el nivel de conocimiento actual sobre estas enzimas en no-vertebrados, comparándolas con las de mamíferos. Evaluar la contribución de estos estudios al conocimiento del rol de las glutinatión transferasas en general, e intentar discernir la dirección de las futuras investigaciones en este campo