Atrazine affects the morphophysiology, tissue homeostasis and aromatase expression in the efferent ductules of adult rats with mild alterations in the ventral prostate

Synergistic mechanism and environmental behavior of tank-mix adjuvants to topramezone and atrazine

An effective way to reduce herbicide quantity is to use adjuvants in order to optimize the amount of herbicide and improve its control efficiency. In order to screen for efficient herbicide tank-mix adjuvants, improve the control of weeds in maize fields, reduce the amount of effective ingredients, and improve the adsorption and digestion behavior of herbicides in soil, this study evaluated the synergistic effects and soil behavior of four types of tank-mix adjuvants combined with herbicides. Different types of adjuvants can enhance herbicide production. Surface tension was significantly reduced by 13% after the pesticide solution was applied with AgroSpred™ Prime. The contact angle with the foliar surface was significantly reduced and solution wettability improved using Atp Lus 245-LQ-(TH). The permeability of topramezone and atrazine in leaves of Amaranthus retroflexus L. and Digitaria sanguinalis (L.) Scop. was increased by 22-96% after adding either tank-mix adjuvant. The solution drying time and maximum retention on leaves were not affected by the tank-mix adjuvants. Ethyl and methylated vegetable oils can reduce the adsorption of topramezone in the soil, thus reducing its half-life in soil. The tank-mix adjuvants had no significant effect on soil dissipation or adsorption of atrazine. AgroSpred™ Prime and Atp Lus 245-LQ-(TH) have the best synergistic effect on topramezone and atrazine in the control of A. retroflexus L. and D. sanguinalis (L.) Scop. in maize fields.

Effect of atrazine on testicular toxicity involves accommodative disorder of xenobiotic metabolizing enzymes system and testosterone synthesis in European quail (Coturnix coturnix)

Due to the wide use of atrazine (ATR), the concern has increased regarding the negative impact of ATR on reproduction. Nevertheless, the reproductive effects caused by different exposure concentrations and the severity of toxic damage are poorly understood. In organisms, ATR is metabolized and degraded through phase II enzyme systems, and changes in cytochrome P450 (CYP) enzymes may have a regulatory role in the harm of ATR. However, less information is available on the induction of CYPs by ATR in avian organisms, and even less on its effects on the testis. Birds are exposed to ATR mainly through food residues and contaminated water, the purpose of this study was to examine reproductive toxicity by different exposure concentrations and elaborate metabolic disorders caused by ATR in European quail (Coturnix coturnix). In this study, the quail were given ATR at 50 mg/kg, 250 mg/kg and 500 mg/kg by oral gavage for 45 days, and the testicular weight coefficients, histopathology and ultrastructure of testes, primary biochemical functions, sex steroid hormones, critical protein levels in the testosterone synthesis pathway, the expression of genes involved CYPs, gonad axis and nuclear receptors expression were investigated. Altogether, testicular coefficient decreased significantly in the high-dose group (1.22%) compared with the control group (3.03%) after 45 days of ATR exposure, and ATR is a potent CYP disruptor that acts through the NXRs and steroid receptor subfamily (APND, CAR, ERND and ERα) without a dose-dependent manner. Notably, ATR interfered with the homeostasis of hormones by triggering the expression of hormones on the gonad axis (LH and E2). These results suggest that exposure to ATR can cause testicular toxicity involving accommodative disorder of phase II enzyme and testosterone synthesis in European quail.

Effects of endocrine active contaminating pesticides on RACK1 expression and immunological consequences in THP-1 cells

We have previously demonstrated that RACK1, which expression is under steroid hormone control, plays an important role in the activation of immune cells and its expression can be useful to evaluate the immunotoxic profile of endocrine disrupting chemicals (EDCs). Hence, we investigated the effects of three contaminating and persistent pesticides: the fungicide vinclozolin (VIN), the herbicide atrazine (ATR) and the insecticide cypermethrin (CYP) on RACK1 expression and on innate immune response. VIN resulted in modest alteration of RACK1 while ATR and CYP reduced in a dose dependent manner RACK1 expression, ultimately leading to the decrease in lipopolysaccharide-induced IL-8 and TNF-α release and CD86 and CD54 surface marker expression. Moreover, our data indicate that, after exposure to EDCs, alterations of RACK1 expression can also occur with mechanisms not directly mediated by an interaction with a nuclear or membrane steroid receptors. Therefore, RACK1 could represent a useful EDCs screening tool to evaluate their immunotoxic potential and to dissect their mechanisms of action.

Carryover effect of atrazine and its metabolite-from treated bovine spermatozoa to the embryo's transcriptome†

Atrazine (ATZ) is an extensively used herbicide and ubiquitous environmental contaminant. ATZ and its metabolite, diaminochlorotriazine (DACT), cause several cellular and functional alterations in spermatozoa. We aimed to examine the effect of ATZ/DACT on spermatozoon DNA integrity, fertilization competence, embryonic development, and transcriptome profile of in vitro-produced embryos derived from fertilization with pre-exposed sperm. Bovine spermatozoa exposed to ATZ (0.1 or 1 μM) or DACT (1 or 10 μM) during in vitro capacitation were used for in vitro fertilization of untreated oocytes. Cleavage and blastocyst-formation rates were evaluated 42 h and 7 days postfertilization, respectively. The association between DNA fragmentation and apoptosis (annexin V kit) was determined. Fertilization competence of annexin-positive (AV+) and annexin-negative (AV-) spermatozoa was examined. Microarray analysis was performed for 7-day blastocysts. Intracytoplasmic sperm injection was performed with control (AV+, AV-) and DACT (AV+, AV-) spermatozoa. Cleavage rates did not differ between groups and blastocyst formation tended to be higher for AV- vs. AV+ in both control and DACT groups, suggesting that acrosome reaction, rather than DNA fragmentation, underlies the reduced cleavage. Transcriptomic analysis revealed 139 and 230 differentially expressed genes in blastocysts derived from ATZ- and DACT-exposed spermatozoa, respectively, relative to controls. Proteomic analysis shown differential expression of proteins in ATZ- or DACT-treated spermatozoa, in particular proteins related to cellular processes and biological pathways. Therefore, we assume that factors delivered by the spermatozoa, regardless of DNA fragmentation, are also involved. Overall, the current study reveals a deleterious carryover effect of ATZ/DACT from the spermatozoa to the developing embryo.

Biotechnological Advances in the Design of Algae-Based Biosensors

In addition to their use in biomass production and bioremediation, algae have been extensively exploited in biosensing applications. Algae-based biosensors have demonstrated potential for sensitive, sustainable, and multiplexed detection of analytes of agroenvironmental and security interest. Their advantages include the availability of different algal bioreceptors including whole cells and their photosynthetic subcomponents, their potential to be integrated into dual transduction miniaturized devices, and the opportunity for continuous environmental monitoring. Despite obstacles including limited stability and selectivity, algae-based biosensing is a realistic prospect that has some recent effective applications. Strategic exploitation of cutting-edge technologies including materials science, nanotechnology, microfluidics, and genome editing will help to achieve the full potential of algae-based sensors.

Effect of the herbicide atrazine and its major metabolite, DACT, on bovine sperm cryotolerance

During freezing and thawing procedures, sperm are exposed to chemical and/or physical stressors that may cause adverse and harmful changes to sperm membranes. Accurate evaluation of the structural and functional integrity of fresh as well as cryopreserved sperm is highly important in predicting sperm fertilization capacity and success of artificial insemination (AI). The herbicide atrazine (ATZ) and its major metabolite, diaminochlorotriazine (DACT) are considered a ubiquitous environmental contaminants and endocrine disruptors, which deleteriously effect sperm function. Taking into consideration possible damage caused by environmental contaminants to sperm membranes, additive effects during cryopreservation cannot be ruled out. The aim of the current study was to evaluate the effect of ATZ (0.1 or 1 μM) and DACT (1 or 10 μM) exposure during or after cryopreservation on bovine sperm cryotolerance. Sperm membrane integrity and functionality were evaluated using fluorimetric probes: (1) double-stranded DNA was examined by 4',6-diamidino-2-phenylindole; (2) plasma membrane integrity was examined by propidium iodide; (3) acrosome reaction (AR) was examined by fluorescein isothiocyanate-conjugated Pisum sativum agglutinin; mitochondrial membrane potential (ΔΨm) was examined by 5,5',6,6'-tetra-chloro-1,1',3,3'-tetraethylbenzimidazolyl carbocyanine iodide fluorescent probe. The findings demonstrate, that exposure of sperm to ATZ (0.1 or 1 μM) or DACT (1 or 10 μM) during cryopreservation increased the proportion of dead sperm relative to the control (P < 0.09); exposure to DACT (1 or 10 μM) increased ΔΨm (P < 0.03). Neither ATZ nor DACT affected spontaneous AR. In contrast, the proportion of sperm with Ca⁺⁺ ionophore-induced AR was lower after exposure to 1 μM DACT (P < 0.05). Following freezing and thawing procedures, exposing sperm to 1 μM ATZ increased the proportion of dead sperm relative to the control (P < 0.05), but had no significant effect on sperm ΔΨm or AR. In conclusion, exposing sperm to endocrine-disrupting chemicals such as ATZ or DACT during cryopreservation reduces sperm cryotolerance and resistance post-thawing.

Seasonal variation of cell proliferation and apoptosis in the efferent ductules and epididymis of the Neotropical bat Artibeus lituratus (Chiroptera, Phyllostomidae)

The balance between cell proliferation and apoptosis is important for maintenance of male fertility, being influenced by a variety of stimuli including androgens and estrogens. However, studies concerning regulation of these processes along the male reproductive tract under physiological conditions are scarce. Therefore, in this study, we investigated the profile of cell proliferation and apoptosis in the efferent ductules and epididymis of the Neotropical bat Artibeus lituratus, a seasonal breeder that presents natural variation in components of the androgen and estrogen responsive systems along the circannual cycle. Low rates of cell proliferation and apoptosis were found in the efferent ductules and epididymis of A. lituratus during the reproductive period, as few epithelial cells were positive for MCM7 (proliferation marker) and cleaved caspase-3 or TUNEL (apoptosis markers). In contrast, during the regressive period, the rate of both proliferating and apoptotic cells was significantly higher in the epithelium lining the efferent ductules as well as throughout the epididymis. The increased proliferative activity at this phase was positively correlated with the expression of estrogen receptor alpha (ERα), whereas the variation in apoptosis appears to be unrelated to the local expression of androgen and estrogen receptors. Together, these data suggest that cell proliferation and apoptosis are differentially modulated in the efferent ductules and epididymis of A. lituratus during the annual reproductive cycle, and support the hypothesis that ERα may be important in preparing the male reproductive tract for sexual recrudescence.