Cytogenetic studies on the effect of feeding mice with stored wheat grains treated with malathion

Malathion or diazinon exposure and male reproductive toxicity: a systematic review of studies performed with rodents

Malathion and diazinon are pesticides commonly used in agriculture to avoid insects that damage crops; however, they may cause impairment to the male genital system of exposed humans. The present work carried out a systematic review of the literature concerning the primary studies that assessed the reproductive effects resulting from male rats and mice exposed to malathion or diazinon. The search for articles was performed on the databases PubMed, LILACS, Scopus, and SciELO, using different combinations of the search terms "malathion," "diazinon," "mice," "rats," "male reproduction," "fertility," and "sperm," followed by the Boolean operators AND or OR. The results obtained indicate that both pesticides act as reproductive toxicants by reducing sperm quality, diminishing hormonal concentrations, inducing increased oxidative stress, and provoking histopathological damage in reproductive organs. Then, the exposure to malathion and diazinon may provoke diminished levels of testosterone by increasing acetylcholine stimulation in the testis through muscarinic receptors, thus, providing a reduction in steroidogenic activity in Leydig cells, whose effect is related to lower levels of testosterone in rodents, and consequently, it is associated with decreased fertility. Considering the toxic effects on the male genital system of rodents and the possible male reproductive toxicity in humans, it is recommended the decreased use of these pesticides and their replacement for others that show no or few toxic effects for non-target animals.

Evaluation of genoprotection against malathion induced toxicity by Orthosiphon thymiflorus Sleesen

BACKGROUND

Pesticide toxicity is considered to be one of the significant reason for increased incidence of cancer. Plants are treasure troves of active phytochemical compounds which are used as herbal medicine as well as nutraceuticals.

OBJECTIVE

To evaluate the genoprotective potential of Orthosiphon thymiflorus (Roth) Sleesen, (Lamiaceae) against the toxicity induced by malathion by a battery of four in vivo assays in Swiss albino mice.

MATERIALS AND METHODS

Micronucleus assay was performed for analyzing the micronuclei induction and ratio of polychromatic and normochromatic erythrocytes (PCE/NCE). Anticlastogenic and mito depressive effect of the methanol and hexane extracts of O.thymiflorus were evaluated by chromosome aberration assay. Alkali comet assay was performed to assess double strand DNA repair. DNA damage sensing ability of the bone marrow cells were assessed by γ-H2AX foci formation. Phytochemical screening of hexane and methanol extract was done by GC-MS analysis.

RESULT

O. thymiflorus extracts showed a dose dependant protective effect in all assays. It significantly decreased the frequency of micronuclei and improved PCE/NCE value in post treated groups of animals. Malathion induced clastogenic aberrations were effectively attenuated by methanol and hexane extracts. DNA comet assay showed that malathion induced damage can be protected by O. thymiflorus extracts. Multiple foci formation in γ-H2AX assay confirmed the activation of DNA repair proteins in post treated animals.

CONCLUSION

Genoprotective effect of O. thymiflorus against malathion induced toxicity was confirmed. This study would be helpful to initiate more research including clinical using O. thymiflorus extract against pesticide induced toxicity.

Morus alba Prevented the Cyclophosphamide Induced Somatic and Germinal Cell Damage in Male Rats by Ameliorating the Antioxidant Enzyme Levels

Cytogenetic analysis is essential to determine the effect of mutagens and antimutagens on genetic material. This study was done to evaluate the protective effect of root bark extract of Morus alba (M. alba) against cyclophosphamide induced somatic and germinal cell damage in male rats. The ethanolic extract of M. alba (0.25, 0.5 and 1 g/kg, 2 weeks) was evaluated against cyclophosphamide (75 mg/kg, single dose) induced nuclear damage. The sampling was done after 48 h of the clastogen treatment. The somatic and germinal nuclear damage was studied by bone marrow micronucleus and sperm analysis, respectively. Serum superoxide and catalase levels were estimated to determine the antioxidant status in each group. The results were analyzed statistically to find the significant variation. The administration of M. alba for 2 weeks suppressed dose-dependently the changes induced by cyclophosphamide. M. alba (0.5 g/kg) decreased the frequency of micronucleated erythrocyte, sperm shape abnormality and enhanced the sperm count, sperm motility and polychromatic-normochromatic erythrocytes ratio significantly (p < 0.05) in comparison with the cyclophosphamide treated group. The highest tested dose of M. alba (1 g/kg) produced more prominent suppression (p < 0.01) in the cyclophosphamide-induced somatic and germinal cell defects. The results also showed significant (p < 0.05) improvement in the serum antioxidant enzymes levels with M. alba when compared with the challenge group. The lower dose of M. alba extract (0.25 g/kg) prevented the CP-induced changes but was found to be statistically insignificant. Therefore, antimutagenic potential of the high dose of the extract of M. alba is possibly due to its antioxidant nature. The ability of the M. alba extract to prevent the nuclear damage could play an important role in overcoming several mutational defects that are associated with anticancer chemotherapy.

Amelioration of the cyclophosphamide induced genotoxic damage in mice by the ethanolic extract of Equisetum arvense

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Plants like E. arvense posess not only nutritional value but therapeutic value as well.

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CPA is an important chemotherapeutic agent but is associated with various mutagenic and other toxic side effects.

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Ethanolic extract of the plant has immense protective effect against the genotoxic damage induced by the cyclophosphamide.

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GC–MS analysis of the extract shows various important phyto components which may be associated with its antimutagenic property.

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Plant can be used in cancer as a chemopreventive agent or even as a coadjuvant to chemotherapy to reduce the side effects associated with it.

In the present study, we evaluated the potential of the plant E. arvense against the cytotoxic and mutagenic effects induced by cyclophosphamide (chemotherapeutic agent) in the bone marrow cells of mice using the Chromosome assay (CA) and Mitotic index (MI) in vivo as the biomarkers. The study was performed following 3 protocols: pre-treatment, simultaneous treatment and post-treatment with the ethanolic extract of the plant. The results demonstrated that the plant extract was not cytotoxic and mutagenic and has a protective effect against the mutagenicity induced by cyclophosphamide in pre, simultaneous and post treatments and against its cytotoxicity as well. Because of its ability to prevent chromosomal damage, E. arvense is likely to open an interesting field concerning its possible use in clinical applications, most importantly in cancer as a chemopreventive agent or even as a coadjuvant to chemotherapy to reduce the side effects associated with it.

Two-dimensional proteomic analysis of gonads of air-breathing catfish, Clarias batrachus after the exposure of endosulfan and malathion

Endocrine disrupting chemicals have raised public concern, since their effects have been found to interfere with the physiological systems of various organisms, especially during critical stage of development and reproduction. Endosulfan and malathion, pesticides widely used for agricultural purposes, have been known to disrupt physiological functions in aquatic organisms. The current work analyzes the effects of endosulfan (2.5 parts per billion [ppb]) and malathion (10 ppb) on the reproductive physiology of catfish (Clarias batrachus) by evaluating protein expression profiles after 21 days of exposure. The proteomic profile of testis and ovary after exposure to endosulfan showed downregulation of proteins such as ubiquitin and Esco2, and upregulation in melanocortin-receptor-2 respectively. Malathion exposed ovary showed upregulated prolactin levels. Identification of proteins differentially expressed in gonads due to the exposure to these pesticides may serve as crucial indications to denote their disruptive effects at the level of proteins.

Cytogenetic evaluation of malathion-induced toxicity in Sprague-Dawley rats

Malathion is a well known pesticide and is commonly used in many agricultural and non-agricultural settings. Its toxicity has been attributed primarily to the accumulation of acetylcholine (Ach) at nerve junctions, due to the inhibition of acetylcholinesterase (AChE), and consequently overstimulation of the nicotinic and muscarinic receptors. However, the genotoxicity of malathion has not been adequately studied; published studies suggest a weak interaction with the genetic material. In the present study, we investigated the genotoxic potential of malathion in bone marrow cells and peripheral blood obtained from Sprague-Dawley rats using chromosomal aberrations (CAs), mitotic index (MI), and DNA damage as toxicological endpoints. Four groups of four male rats, each weighing approximately 60 ± 2g, were injected intraperitoneally (i.p.) once a day for five days with doses of 2.5, 5, 10, and 20mg/kg body weight (BW) of malathion dissolved in 1% DMSO. The control group was made up of four animals injected with 1% DMSO. All the animals were sacrificed 24h after the fifth day treatment. Chromosome preparations were obtained from bone marrow cells following standard protocols. DNA damage in peripheral blood leukocytes was determined using alkaline single-cell gel electrophoresis (comet assay). Malathion exposure significantly increased the number of structural chromosomal aberrations (CAs) and the percentages of DNA damage, and decreased the mitotic index (MI) in treated groups when compared with the control group. Our results demonstrate that malathion has a clastogenic/genotoxic potential as measured by the bone marrow CA and comet assay in Sprague-Dawley rats.

Multi residue analysis of pesticides in wheat and khat collected from different regions of Ethiopia

The present study investigated the presence and level of pesticide residues in wheat and khat samples collected from various localities of Ethiopia. The khat samples from Galemso and Aseno had p,p'-DDT concentrations ranged from 141.2 to 973.0 μg/Kg and 194.3-999.0 μg/Kg, respectively. Diazinon was detected in all the khat samples from BadaBuna (173.9-686.9 μg/Kg) but not in any of the samples from Galemso and Aseno. Diazinon was detected in all the wheat samples obtained from both Arsi and Bale (125.8 and 125.6 μg/Kg, respectively) and aldrin levels in these samples were below the quantification limit. Khat may be a contributing factor in the pathological diseases found among khat users.

Effects of chronic dietary exposure to a low-dose of Malathion, Aroclor-1254 and 3-methylcholanthrene on three biomarkers in male mice

The aim of this research was to examine the applicability of some chronic toxicological tests in the determination of exposure to xenobiotics present in concentrations below No Observed Adverse Effect Level (NOAEL) and below the detection limit of analytical instruments. In the present experiment tested chemicals (Malathion, Aroclor-1254 and 3-methylcholanthrene (3-MC)) were mixed with wheat grains and given to male mice as feed over a period of 12 months. 7-ethoxyresorufin-O-deethylase (EROD) activity with the 3-MC and Aroclor-1254 treatments reached the peak at 9th month of exposure (26.7 and 42.4 pmol⁻¹ mg(prot)-⁻¹, respectively), while malathion did not have significant influence. Glutathione (GSH) level depletion was highest after three months of exposure. Unexpectedly, acetylcholinesterase (AChE) activity increased after treatment with malathion, an organophosphorous insecticide. In conclusion, low-level concentrations chronically administered exert certain effects on the levels of selected enzymes, e.g. biomarkers.

Effects of the insecticides malathion and diazinon on the early oogenesis in mice in vitro

Malathion and diazinon are two of the most commonly used organophosphorous (OP) agrochemicals. Several studies show that these pesticides exert several effects on mammalian spermatogenesis. Nevertheless, there are no studies concerning their effects on oogenesis. The objective of this study was to evaluate the effects of these insecticides on the viability of in vitro cultured mouse oocytes during the early oogenesis and to get a further understanding of the molecular mechanisms by which OP insecticides act and affect germinal cells. Oocytes were cultured from fetal ovaries for 10 days, when most oocytes had reached the diplotene stage (germinal vesicle stage). Cultures were exposed to different concentrations of malathion or diazinon for 24 h, and the effect on oocyte viability was assessed. Gene expression in oocytes exposed to the insecticides was analyzed by generating cDNA libraries and performing differential screenings. Results show a significant decrease in oocytes survival after 24-h exposure to 250 microM malathion or 900 nM diazinon, and the effect of these insecticides on the regulation of genes encoding proteins involved in transcription (BP75), translation (ribosomal protein S5), and mitochondrial function (cytochrome oxidase subunits I and III), providing evidence for OP insecticides as toxicants for mammals oocytes during the early oogenesis.

Effect of subchronic exposure to malathion on glycogen phosphorylase and hexokinase activities in rat liver using native PAGE

The aim of this study was the evaluation of the effects of a subchronic exposure to malathion, an organophosphorus (OP) insecticide, on plasma glucose and hepatic enzymes of glycogenolysis and glycolysis in rats in vivo. Malathion was administered intragastrically by stomach tube in the amount of 1 ml corn oil containing 100mg/kg body weight (BW) daily for 32 days. At the end of the experiment, the liver was removed. The activities of glycogen phosphorylase (GP) and hexokinase (HK) were analysed in the homogenate. The methodology employed was a non-denaturing electrophoresis followed by activity-staining (native PAGE). Malathion decrease GP activity by 50% and increase HK activity by 10%. In addition, an hepatomegaly was recorded with a rise in the hepatic glycogen rate in malathion-treated rats. Moreover, subchronic administration of malathion has no effect on blood glucose concentration. The storage of glycogen in liver may be due to a stimulation of insulin secretion after the inhibition of acethylcholinesterase activity in pancreatic beta cells by malathion. These findings were in favour of an activation of glycogen storage by malathion.