The environmental endocrine disruptor, bisphenol A, affects germination, elicits stress response and alters steroid hormone production in kiwifruit pollen

Futuristic advancements in phytoremediation of endocrine disruptor Bisphenol A: A step towards sustainable pollutant degradation for rehabilitated environment

Bisphenol A (BPA) accumulates in the environment at lethal concentrations because of its high production rate and utilization. BPA, originating from industrial effluent, plastic production, and consumer products, poses serious risks to both the environment and human health. The widespread aggregation of BPA leads to endocrine disruption, reactive oxygen species-mediated DNA damage, epigenetic modifications and carcinogenicity, which can disturb the normal homeostasis of the body. The living being in a population is subjected to BPA exposure via air, water and food. Globally, urinary analysis reports have shown higher BPA concentrations in all age groups, with children being particularly susceptible due to its occurrence in items such as milk bottles. The conventional methods are costly with a low removal rate. Since there is no proper eco-friendly and cost-effective degradation of BPA reported so far. The phytoremediation, green-biotechnology based method which is a cost-effective and renewable resource can be used to sequestrate BPA. Phytoremediation is observed in numerous plant species with different mechanisms to remove harmful contaminants. Plants normally undergo several improvements in genetic and molecular levels to withstand stress and lower levels of toxicants. But such natural adaptation requires more time and also higher concentration of contaminants may disrupt the normal growth, survival and yield of the plants. Therefore, natural or synthetic amendments and genetic modifications can improve the xenobiotics removal rate by the plants. Also, constructed wetlands technique utilizes the plant's phytoremediation mechanisms to remove industrial effluents and medical residues. In this review, we have discussed the limitations and futuristic advancement strategies for degrading BPA using phytoremediation-associated mechanisms.

The Role of Plant Progesterone in Regulating Growth, Development, and Biotic/Abiotic Stress Responses

Progesterone is a steroid hormone that performs important functions in mammals. However, studies on its physiological functions in plants have gradually increased in recent years. Therefore, this review summarizes the regulatory functions of progesterone on plant growth and development, as well as its response to stress. Moreover, the plant metabolic processes of progesterone are also discussed. Overall, progesterone is ubiquitous in plants and can regulate numerous plant physiological processes at low concentrations. Since progesterone shares similar characteristics with plant hormones, it is expected to become a candidate for plant hormone. However, most of the current research on progesterone in plants is limited to the physiological level, and more molecular level research is needed to clarify progesterone signaling pathways.

Ecotoxicity and Biodegradation of Sustainable Environment-Friendly Bone-Glue-Based Adhesive Suitable for Insulation Materials

Bone glue with sodium lignosulfonate is a protein-based adhesive. Their combination leads to strong binding necessary for the achievement of adhesive properties. However, biodegradation and ecotoxicity of materials composed of bone glue and sodium lignosulfonate has never been studied before. In this paper, the biodegradation potential of the mixture of bone glue, lignosulfonate and rape straw modified by water or NaOH on an agar test with aerial molds and in acute aquatic tests with mustard, yeasts, algae and crustaceans was analyzed. Epoxy resin as an ecologically unfriendly binder was used as a negative control and pure rape straw as a background. The results indicated that all samples were covered by molds, but the samples containing straw treated by NaOH showed lower biodegradability. The ecotoxicological effects varied among the applied model organisms. Artemia salina was not able to survive and S. alba could not prolong roots in the eluates of all samples (100% inhibition). Freshwater algae (D. subspicatus) were not significantly affected by the samples (max. 12% inhibition, max. 16% stimulation). The biomass of yeasts (S. cerevisae) was strongly stimulated in the presence of eluates in a comparison to control (max. 38% stimulation).

Estrogens and Androgens in Plants: The Last 20 Years of Studies

Although the only known steroid hormones in plants are brassinosteroids, interestingly, mammalian steroid hormones such as androgens or estrogens are also part of the plant metabolic profile. This presented review is focused on the progress that has been made in this matter during the last two decades. The presence of testosterone, 17β-estradiol, and other androgens/estrogens in plants (particularly those that can be measured using more advanced techniques) is described. The physiological activity of androgens and estrogens, especially in plants’ stress response, are discussed, together with some possible mechanisms of their action. The current knowledge indicates that although androgens and estrogens do not have the status of hormones in plants, they are physiologically active and can serve as regulators that support the activity of classic hormones in (1) regulating the various processes connected with plant growth and development and (2) the interaction of plants with their environment.

Melatonin promotes metabolism of bisphenol A by enhancing glutathione-dependent detoxification in Solanum lycopersicum L

Bisphenol A (BPA), a widely distributed organic compound, is toxic to animals and plants. Here we show the mechanism of BPA detoxification by melatonin (MEL) in tomato, which is otherwise poorly understood in plants. BPA treatment decreased the quantum yield of photosystem II (Fv/Fm) and increased the membrane lipid peroxidation and reactive oxygen species (ROS) accumulation dose-dependently, whereas exogenous MEL alleviated the BPA effects on Fv/Fm, lipid peroxidation, ROS accumulation and BPA uptake. Furthermore, BPA elevated the glutathione (GSH) content, activities of glutathione S-transferase (GST), and glutathione reductase (GR), and the transcript levels of GSH1, GR1, GST1 and MEL biosynthesis genes (COMT, T5H, and SNAT), whereas BPA + MEL showed even a more profound induction. Silencing GSH1, GR1 and GST1 genes compromised the BPA detoxification potential of tomato plants as revealed by an increased level of ROS, lipid peroxidation and BPA uptake, and a decreased Fv/Fm and GST activity; these changes were alleviated by MEL application. Under in vitro conditions, BPA was glutathionylated by GSH, which was further catalyzed by GST to cysteine and N-acetylcysteine conjugates. These findings suggest a crucial role for MEL in BPA detoxification via GSH and GST, and can be useful to reduce BPA residue for food safety.

Dopamine alleviates bisphenol A-induced phytotoxicity by enhancing antioxidant and detoxification potential in cucumber

Bisphenol A (BPA) is an emerging organic pollutant, widely distributed in environment. Plants can uptake and metabolize BPA, but BPA accumulation induces phytotoxicity. In this study, we administered dopamine, a kind of catecholamines with strong antioxidative potential, to unveil its role in cucumber tolerance to BPA stress. The results showed that exposure to BPA (20 mg L^-1) for 21 days significantly reduced growth and biomass accumulation in cucumber seedlings as revealed by decreased lengths and dry weights of shoots and roots. While BPA exposure decreased the chlorophyll content, cell viability and root activity, it remarkably increased reactive oxygen species (ROS) accumulation, electrolyte leakage and malondialdehyde (MDA) content, suggesting that BPA induced oxidative stress in cucumber. However, exogenous dopamine application significantly improved the photosynthetic pigment content, root cell viability, growth and biomass accumulation, and decreased the ROS and MDA levels by increasing the activity of antioxidant enzymes under BPA stress. Further analysis revealed that dopamine application significantly increased the glutathione content and the transcripts and activity of glutathione S-transferase under co-administration of dopamine and BPA compared with only BPA treatment. Moreover, dopamine decreased the BPA content in both leaves and roots, suggesting that dopamine promoted BPA metabolism by enhancing the glutathione-dependent detoxification. Our results show that dopamine has a positive role against BPA phytotoxicity and it may reduce the risks-associated with the dietary intake of BPA through consumption of vegetables.

Hazards of bisphenol A (BPA) exposure: A systematic review of plant toxicology studies

The widespread use of bisphenol A (BPA) has led to its ubiquity in the natural environment. Thus, BPA is considered as a contaminant of emerging concern. Due to its widespread use, BPA has been detected in a range of soils and surface waters. This is of concern because BPA has been shown to elicit slight to moderate toxicity to plants. Based on current research and our own work, this paper reviews the toxic effects of BPA on plant growth and development, including effects at the macroscopic (e.g. seed germination, root, stem, and leaf growth) and microscopic (photosynthesis, uptake of mineral nutrient, hormone secretion, antioxidant systems, and reproductive genetic behavior) levels. Furthermore, this paper will discuss effects of BPA exposure on metabolic reactions in exposed plant species, and explore the use of high-efficiency plants in BPA pollution control (e.g. phytoremediation). Finally, this paper proposes some ideas for the future of BPA phytotoxicity research.

Lifestyle and environmental contributions to ovulatory dysfunction in women of polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common reason of anovulatory infertility. Environmental factor is one of the main causes of PCOS, but its contribution to ovulatory dysfunction in PCOS remains unknown.

METHODS

A total of 2217 infertile women diagnosed as PCOS according to Rotterdam criteria were recruited, including 1979 women with oligo-anovulation (OA group) and 238 women with normal -anovulation (non OA group). Besides, 279 healthy control women of reproductive age were enrolled as controls.

RESULTS

Frequencies of snoring (PCOS-OA group, PCOS-non-OA group, control group: 29.30% vs 18.10% vs 11.50%, P < 0.01), smoking (37.70% vs 28.10% vs 12.20%, P < 0.01), plastic tableware usage (38.30% vs 28.10% vs 25.40%, P < 0.01) and indoor decoration (32.10% vs 24.80% vs 16.80%, P < 0.01) were highest in PCOS-OA group. After adjusted for multivariable, difference remained significant between PCOS-OA group and the other two groups. PCOS-OA women preferred a meat favorable diet compared to PCOS-non-OA group (54.60% vs 41.30%, P < 0.01). There was no difference between three groups in exercise, frequency of insomnia, and alcohol consumption.

CONCLUSIONS

Smoking, snoring, hyper-caloric diet, plastic tableware usage and indoor decoration were found to be associated with an increased risk for ovulatory dysfunction in women suffering from PCOS.

Plants are Capable of Synthesizing Animal Steroid Hormones

As a result of the findings of scientists working on the biosynthesis and metabolism of steroids in the plant and animal kingdoms over the past five decades, it has become apparent that those compounds that naturally occur in animals can also be found as natural constituents of plants and vice versa, i.e., they have essentially the same fate in the majority of living organisms. This review summarizes the current state of knowledge on the occurrence of animal steroid hormones in the plant kingdom, particularly focusing on progesterone, testosterone, androstadienedione (boldione), androstenedione, and estrogens.

Effects of bisphenol A in soil on growth, photosynthesis activity, and genistein levels in crop plants (Vigna radiata)

The compound bisphenol A (BPA), an endocrine-disrupting compound that can act as an estrogen, is widely used in the industrial manufacture of plastic products and epoxy resins. Because of the widespread use of the compound and its use in soil amendments, there is concern regarding its effects on crop plants, although comparatively little information is available on the ecotoxicity and potential risk of bisphenol. Here, we investigated the toxicity of BPA on mung bean (Vigna radiata) by evaluating growth, photosynthesis parameters, and phytoestrogen changes. Adverse effects on shoot growth were observed at a dose of 750 mg BPA/kg dry soil after acute (14 days) and chronic (21 days) exposure, and inhibition of root development was confirmed at a dose of 1000 mg BPA/kg dry soil. Chlorophyll content and stomatal size decreased at doses of 250 and 500 mg BPA/kg dry soil, respectively, and leaf spots due to leaf necrosis were observed in the groups that received 250 mg BPA/kg dry soil. Photosynthetic activity appeared to decrease in the groups that received the highest exposure, although it was not statistically significant. Meanwhile, exposure to bisphenol A increased the level of the phytoestrogen genistein. We propose that changes in genistein levels due to endocrine-disrupting compounds can be considered as a specific toxicity endpoint for endocrine-disrupting chemicals; further studies should explore this effect. This study confirmed the phytotoxicity of BPA at various endpoints and the results provide a basis for future ecological risk assessment for BPA.

Reactive oxygen species initiate a protective response in plant roots to stress induced by environmental bisphenol A

Bisphenol A (BPA), a contaminant of emerging concern, can affect plant growth and development at high concentrations. Reactive oxygen species (ROS) production is a general primary response in plants to stress. Here, the aim is to investigate whether ROS in plants play protective roles for stress induced by BPA exposure at environmental concentrations. In this study, soybean roots (seedling, flowering and podding stages) were exposed to 1.5 and 3.0 mg L-1 BPA, and ROS response was measured. The relationship between ROS levels and residual BPA content in soybean roots was evaluated. The results showed that exposure (9 h) to 1.5 mg L-1 BPA elicited changes in ROS production. ROS then gradually accumulated in soybean roots (seedling stage). Exposure to 3.0 mg L-1 BPA elicited a stronger and earlier ROS responses at the flowering and podding stage, but did not lead to membrane lipid peroxidation. Residual BPA content in soybean roots reached peak concentrations after 9 h of exposure, and then gradually decreased at the flowering and podding stage. These results indicate that ROS in soybean roots might be involved in the oxidative metabolism of BPA, which could prevent BPA from damaging exposed plants. In conclusion, the observed ROS metabolic effects may be self-protection responses of plants to stress induced by BPA exposure.

A preliminary analysis of the effects of bisphenol A on the plant root growth via changes in endogenous plant hormones

Bisphenol A (BPA) is ubiquitous in the environment worldwide, affecting plant growth and development. Endogenous plant hormones serve as switches that regulate plant growth and development. However, plants have different physiological requirements and environmental adaptive capacities during the different growth stages. Here, we investigated the effects of BPA on soybean (Glycine max L.) root growth at the three growth stages and analyzed the mechanisms underlying the effects of BPA on the root growth by assessing changes in endogenous hormone. The results showed that low concentration of BPA (1.5mgL-1) improved root growth (except at the seed-filling stage), increased indole-3-acetic acid (IAA) content at the first two growth stages, and increased zeatin (ZT) content and decreased gibberellic acid (GA3) content at the seedling stage. But low concentration of BPA caused decreased ethylene (ETH) contents and constant abscisic acid (ABA) content at all three stages. However, BPA at moderate and high concentrations (6.0 and 12.0mgL-1) inhibited root growth, causing the decreased IAA, GA3 and ETH contents and increased ABA content at all three growth stages. The change degrees of above indices were weakened with prolonging the growth stages. After BPA withdrawal, both the root growth and the hormone contents recovered (with the exception of ZT and ETH), and the recovery degrees had negative correlation with the BPA exposure concentration and had positive correlation with the growth stage. Changes in residual BPA content in the roots were also observed at different BPA concentrations and different growth stages. Our results demonstrated the effects of BPA on root growth were related to BPA-induced changes in hormone, which performed differently at various growth stages.

Disruption of actin filaments in Zea mays by bisphenol A depends on their crosstalk with microtubules

Bisphenol A (BPA) is a widespread environmental pollutant, reportedly harmful to living organisms. In plant cells, BPA was shown to disrupt microtubule (MT) arrays and perturb mitosis, but its effects on filamentous actin (F-actin) have not been explored. Here we studied the effects of BPA on actin filaments (AFs) in meristematic root tip and leaf cells of Zea mays, by fluorescent labeling and confocal microscopy. Considering the typical dynamic interaction between MTs and AFs, the effects on these two essential components of the plant cytoskeleton were correlated. It was found that BPA disorganized rapidly AFs in a concentration- and time-dependent manner. The fine filaments were first to be affected, followed by the subcortical bundles, resulting in rod- and ring-like conformations. The observed differences in sensitivity between protodermal and cortex cells were attributed to the deeper location of the latter. Depolymerization or stabilization of MTs by relevant drugs (oryzalin, taxol) revealed that AF susceptibility to BPA depends on MT integrity. Developing leaves required harder and longer treatment to be affected by BPA. Ontogenesis of stomatal complexes was highly disturbed, arrangement of AFs and MT arrays was disordered and accuracy of cell division sequence was deranged or completely arrested. The effect of BPA confirmed that subsidiary cell mother cell polarization is not mediated by F-actin patch neither of preprophase band organization. On the overall, it is concluded that AFs in plant cells constitute a subcellular target of BPA and their disruption depends on their crosstalk with MTs.

Stomatal and non-stomatal factors regulated the photosynthesis of soybean seedlings in the present of exogenous bisphenol A

Bisphenol A (BPA) is an emerging environmental endocrine disruptor that has toxic effects on plants growth. Photosynthesis supplies the substances and energy required for plant growth, and regulated by stomatal and non-stomatal factors. Therefore, in this study, to reveal how BPA affects photosynthesis in soybean seedlings (Glycine max L.) from the perspective of stomatal and non-stomatal factors, the stomatal factors (stomatal conductance and behaviours) and non-stomatal factors (Hill reaction, apparent quantum efficiency, Rubisco activity, carboxylation efficiency, the maximum Rubisco carboxylation velocity, ribulose-1,5-bisphospate regeneration capacities mediated by maximum electron transport rates, and triose phosphate utilization rate) were investigated using a portable photosynthesis system. Moreover, the pollution of BPA in the environment was simulated. The results indicate that low-dose BPA enhanced net photosynthetic rate (Pn) primarily by promoting stomatal factors, resulting in increased relative growth rates and accelerated soybean seedling growth. High-dose BPA decreases the Pn by simultaneously inhibiting stomatal and non-stomatal factors, and this inhibition decreases the relative growth rates further reducing soybean seedling growth. Following the withdrawal of BPA, all of the indices were restored to varying degrees. In conclusion, low-dose BPA increased the Pn by promoting stomatal factors while high-dose BPA decreased the Pn by simultaneously inhibiting stomatal and non-stomatal factors. These findings provide a model (or, hypothesis) for the effects of BPA on plant photosynthesis.

Biochemical responses and ultrastructural changes in ethylene insensitive mutants of Arabidopsis thialiana subjected to bisphenol A exposure

Bisphenol A (BPA), an important raw material in plastic industry, has become a serious environmental contaminant due to its wide spread use in different products and increasing release into the environment. BPA is known to cause adverse effects in living organisms including plants. Several studies reported that BPA affects growth and development in plants, mainly through oxidative stress. Plants are known to generally cope with stress mainly through hormonal regulation and adaptation, but little is known about the role of plant hormones in plants under BPA stress. The present study was conducted to investigate the role of ethylene in BPA induced oxidative stress in plants using Arabidopsis thaliana as a test plant. The response of ethylene insensitive mutants of Arabidopsis (ein2-1 and etr1-3) to BPA exposure was studied in comparison to the wild type Arabidopsis (WT). In all three genotypes, exposure to BPA adversely affected cellular structures, stomata and light-harvesting pigments. An increase in reactive oxygen species (ROS) lipid peroxidation and other oxidative stress markers indicated that BPA induced toxicity through oxidative stress. However, the overall results revealed that WT Arabidopsis had more pronounced BPA induced damages while ein2-1 and etr1-3 mutants withstood the BPA induced stress more efficiently. The activity of antioxidant enzymes and expression of antioxidants related genes revealed that the antioxidant defense system in both mutants was more efficiently activated than in WT against BPA induced oxidative stress, which further evidenced the involvement of ethylene in regulating BPA induced oxidative stress. It is concluded that ethylene perception and signaling may be involved in BPA induced oxidative stress responses in plants.

Bisphenol A effects on the chlorophyll contents in soybean at different growth stages

Bisphenol A (BPA), a suspected endocrine disruptor, can modify normal plant growth and development. Photosynthesis provides material and energy for the growth and development of plants, in which chlorophyll (Chl) plays a significant role. Many studies have shown that the growth and metabolism of plants vary at different growth stages. Thus the sensitivity of plant's responses to environmental pollution is correspondingly different. We studied the effects of BPA on the Chl contents of soybean (Glycine Max L.) at different growth stages (seedling, flowering and podding, seed-filling and maturation) by measuring the contents of essential intermediates (5-aminolevulinic acid, porphobilinogen, protoporphyrin IX, magnesium protoporphyrin and protochlorophyll) and the activities of key enzymes (5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, magnesium chelatase) in chlorophyll synthesis. Low-dose (1.5 mg/L) BPA exposure increased the activities of key enzymes in addition to the contents of intermediates in Chl synthesis at different growth stages, resulting in increases in Chl contents and net photosynthetic rate. In contrast, medium and high-dose (17.2, 50.0 mg/L) BPA exposure produced inhibitory effects on the indices. Following the withdrawal of BPA exposure, the indices recovered to a degree that was related to the plant growth stage. The effect level (high to low) of BPA on these indices at different growth stages was: seedling stage > maturation stage > flowering and podding stage > seed-filling stage. The reverse effect was observed following the withdrawal of BPA exposure. The responses of key enzymes in plant Chl synthesis to BPA illustrate how BPA affects Chl contents. The effects of BPA show clear differences at different plant growth stages.

A pathway of bisphenol A affecting mineral element contents in plant roots at different growth stages

Bisphenol A (BPA), an environmental endocrine disruptor, is an important industrial raw material. The wide use of BPA has increased the risk of BPA release into the environment, and it has become a new environmental pollutant. In this work, the ecological deleterious effects of this new pollutant on soybean roots at different growth stages were investigated by determining the contents of mineral elements (P, K, Ca, and Mg) and analyzing root activity and the activities of critical respiratory enzymes (hexokinase, phosphofructokinase, pyruvate kinase, and isocitrate dehydrogenase). Our results revealed that low dose (1.5mg/L) of BPA increased the levels of P, K, Mg, and Ca in soybean roots at different growth stages. Whereas, high doses (6.0 and 12.0mg/L) of BPA decreased the levels of P, K, and Mg contents in a dose-dependent manner. BPA had a promotive effect on the content of Ca in soybean roots. Synchronous observation showed that the aforementioned dual response to BPA were also observed in the root activity and respiratory enzyme activities. The effects of BPA on the mineral element contents, root activity and respiratory enzyme activities in soybean roots at different growth stages followed the order: flowering and podding stage>seed-filling stage>seedling stage (mineral element contents); seedling stage>flowering and podding stage>seed-filling stage (root activity and respiratory enzyme activities). In a word, the response of plant root activity and respiratory enzyme activities to BPA pollution is a pathway of BPA affecting mineral element contents in plant roots.

The Genomic and Morphological Effects of Bisphenol A on Arabidopsis thaliana

The environmental toxin bisphenol A (BPA) is a known mammalian hormone disrupter but its effects on plants have not been well established. The effect of BPA on gene expression in Arabidopsis thaliana was determined using microarray analysis and quantitative gene PCR. Many hormone responsive genes showed changes in expression after BPA treatment. BPA disrupted flowering by a mechanism that may involve disruption of auxin signaling. The results presented here indicate that BPA is a plant hormone disrupter.

Bisphenol A disrupts microtubules and induces multipolar spindles in dividing root tip cells of the gymnosperm Abies cephalonica

The effects of bisphenol A (BPA), an endocrine chemical disruptor extensively used in the plastic and epoxy resin industry, on dividing root tip cells of the gymnosperm Abies cephalonica Loudon were investigated by confocal laser scanning microscopy after tubulin and endoplasmic reticulum immunolocalization and DNA staining. Microtubule arrays of all mitotic stages were disrupted within a few hours of treatment: preprophase bands exhibited asymmetric width; prometaphase, metaphase and anaphase spindles appeared sharply pointed, sigmoid or multipolar; phragmoplast microtubules were elongated and occasionally bended toward the daughter nuclei. Depending on the mitotic stage, the chromosomes appeared condensed at prophase, as a compact mass at metaphase and anaphase, unsegregated or bridged at telophase. Endoplasmic reticulum patterns were also affected, reflecting those of the respective microtubule arrays. Recovery of the microtubules after oryzalin treatment was more effective in a BPA solution than in water. It is concluded that the plant mitotic apparatus microtubules are very sensitive to BPA, the effect of which depends on the specific cell cycle stage. The formation of multipolar spindles is reminiscent of animal cells and is ascribed to the induction of multiple microtubule nucleation sites, deriving from the centrosomal properties of gymnosperms.

Analysis of effects of a new environmental pollutant, bisphenol A, on antioxidant systems in soybean roots at different growth stages

Bisphenol A (BPA) is an important industrial raw material. Because of its widespread use and increasing release into environment, BPA has become a new environmental pollutant. Previous studies about BPA's effects in plants focus on a certain growth stage. However, the plant's response to pollutants varies at different growth stages. Therefore, in this work, BPA's effects in soybean roots at different growth stages were investigated by determining the reactive oxygen species levels, membrane lipid fatty acid composition, membrane lipid peroxidation, and antioxidant systems. The results showed that low-dose BPA exposure slightly caused membrane lipid peroxidation but didn't activate antioxidant systems at the seedling stage, and this exposure did not affect above process at other growth stages; high-dose BPA increased reactive oxygen species levels and then caused membrane lipid peroxidation at all growth stages although it activated antioxidant systems, and these effects were weaker with prolonging the growth stages. The recovery degree after withdrawal of BPA exposure was negatively related to BPA dose, but was positively related to growth stage. Taken together, the effects of BPA on antioxidant systems in soybean roots were associated with BPA exposure dose and soybean growth stage.

Effects of bisphenol A, an environmental endocrine disruptor, on the endogenous hormones of plants

Bisphenol A (BPA) is a ubiquitous endocrine-disrupting chemical in the environment that exerts potential harm to plants. Phytohormones play important roles both in regulating multiple aspects of plant growth and in plants' responses to environmental stresses. But how BPA affects plant growth by regulating endogenous hormones remains poorly understood. Here, we found that treatment with 1.5 mg L(-1) BPA improved the growth of soybean seedlings, companied by increases in the contents of indole-3-acetic acid (IAA) and zeatin (ZT), and decreases in the ratios of abscisic acid (ABA)/IAA, ABA/gibberellic acid (GA), ABA/ZT, ethylene (ETH)/GA, ETH/IAA, and ETH/ZT. Treatment with higher concentrations of BPA (from 3 to 96 mg L(-1)) inhibited the growth of soybean seedlings, meanwhile, decreased the contents of IAA, GA, ZT, and ETH, and increased the content of ABA and the ratios of ABA/IAA, ABA/GA, ABA/ZT, ETH/GA, ETH/IAA, and ETH/ZT. The increases in the ratios of growth and stress hormones were correlated with the increase in the BPA content of the roots. Thus, BPA could affect plant growth through changing the levels of single endogenous hormone and the ratios of growth and stress hormones in the roots because of BPA absorption by the roots.

Effects of bisphenol A on chlorophyll fluorescence in five plants

The aim of this study was to evaluate the effects of bisphenol A (BPA) on plant photosynthesis and determine whether the photosynthetic response to BPA exposure varies in different plants. Chlorophyll fluorescence techniques were used to investigate the effects of BPA on chlorophyll fluorescence parameters in tomato (Lycopersicum esculentum), lettuce (Lactuca sativa), soybean (Glycine max), maize (Zea mays), and rice (Oryza sativa) seedlings. Low-dose (1.5 or 3.0 mg L(-1)) BPA exposure improved photosystem II efficiency, increased the absorption and conversion efficiency of primary light energy, and accelerated photosynthetic electron transport in each plant, all of which increased photosynthesis. These effects weakened or disappeared after the withdrawal of BPA. High-dose (10.0 mg L(-1)) BPA exposure damaged the photosystem II reaction center, inhibited the photochemical reaction, and caused excess energy to be released as heat. These effects were more evident after the highest BPA dose (17.2 mg L(-1)), but they weakened after the withdrawal of BPA. The magnitude of BPA exposure effects on the chlorophyll fluorescence parameters in the five plants followed the order: lettuce > tomato > soybean > maize > rice. The opposite order was observed following the removal of BPA. In conclusion, the chlorophyll fluorescence response in plants exposed to BPA depended on BPA dose and plant species.

Effects of bisphenol A on key enzymes in cellular respiration of soybean seedling roots

The environmental endocrine disrupter bisphenol A (BPA) is ubiquitous in the environment, with potential toxic effects on plants. Previous studies have found a significant effect of BPA on levels of mineral nutrients in plant roots, but the underlying mechanism remains unknown. To determine how BPA influences root mineral nutrients, the effects of BPA (1.5 mg L(-1) , 3.0 mg L(-1) , 6.0 mg L(-1) , 12.0 mg L(-1) , 24.0 mg L(-1) , 48.0 mg L(-1) , and 96.0 mg L(-1) ) on activities of critical respiratory enzymes (hexokinase, phosphofructokinase, pyruvate kinase, isocitrate dehydrogenase, and cytochrome c oxidase) were investigated in soybean seedling roots. After BPA exposure for 7 d, the low concentrations of BPA increased the activities of critical respiratory enzymes in roots, whereas opposite effects were observed in roots exposed to high concentrations of BPA, and the inhibitory effect was greater for higher BPA concentrations. In addition, evident morphological anomalies and decreases in root lengths and volumes were induced by high concentrations of BPA. Following withdrawal of BPA exposure after 7 d, the activities of respiratory enzymes and visible signs of toxicity recovered, and the extent of recovery depended on the type of enzyme and the BPA concentration. Furthermore, correlation analysis showed that the disturbance by BPA to activities of respiratory enzymes, which led to interference in the energy metabolism in roots, might be an effect mechanism of BPA on mineral element accumulation in plant roots.

Bisphenol A affects germination and tube growth in Picea meyeri pollen through modulating Ca2+ flux and disturbing actin-dependent vesicular trafficking during cell wall construction

Bisphenol A (BPA), a widespread pollutant, is reportedly harmful to humans, animals and plants. However, the effect of BPA on plant pollen tube growth, as well as the mechanism involved, remains unclear. Here, we report that BPA significantly inhibited Picea meyeri pollen germination and tube elongation in a dose-dependent manner. Transmission electron microscopy showed that BPA was detrimental to organelles such as mitochondria and Golgi apparatus. Non-invasive detection revealed that BPA inhibited extracellular Ca(2+) influx and promoted intracellular Ca(2+) efflux at the pollen tube tip, thereby inducing a dissipated Ca(2+) gradient. Fluorescence labeling showed that BPA disorganized actin filaments (AFs), which subsequently led to abnormal vesicle trafficking. Furthermore, BPA reduced the activity of acid phosphatase, a typical exocytosis enzyme. Moreover, Fourier transform infrared (FTIR) analysis and subsequent fluorescence labeling revealed that BPA induced an abnormal deposition of cell wall components, including pectins and callose. Taken together, our results indicate that BPA, a ubiquitous environmental pollutant, disturbs Ca(2+) flux in P. meyeri pollen tubes, thus disrupting AF organization, resulting in abnormal actin-dependent vesicle trafficking and further affecting the deposition of cell wall components. These findings provide new insight into the mechanism of BPA toxicity in pollen tube tip growth.

Effects of bisphenol A on chlorophyll synthesis in soybean seedlings

Bisphenol A (BPA), as an emerging environmental pollutant, is potentially harmful to plant growth. Chlorophyll (Chl) is critical in photosynthesis that provides matter and energy for plant growth. How BPA affects the chlorophyll content remains largely unknown. Here, the effects of BPA on Chl synthesis in soybean seedlings were investigated. Exposure to 1.5 mg/L BPA decreased the 5-aminolevulinic acid (ALA) content and increased protoporphyrin IX (Proto IX), magnesium protoporphyrin, and protochlorophyll contents and 5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, uroporphyrinogen III decarboxylase, and protoporphyrinogen oxidase activities. Exposure to 17.2 and 50.0 mg/L BPA exerted the opposite effects on these four intermediates and five enzymes. Following the withdrawal of BPA exposure, the aforementioned parameters gradually recovered, except magnesium protoporphyrin content in exposure to 50.0 mg/L BPA. Our findings revealed that exposure to low-concentration BPA increased the Chl content in soybean seedlings through improving Chl synthesis, especially the conversion from ALA to Proto IX, whereas exposure to high-concentration BPA decreased the Chl content through inhibiting Chl synthesis, especially the conversion from ALA to Proto IX. The dual effects of BPA were largely reversed following the withdrawal of BPA exposure.

Effects of bisphenol A on mineral nutrition in soybean seedling roots

Bisphenol A (BPA) is a ubiquitous chemical in the environment and potentially harmful to plants. However, relevant studies of the effects of BPA on plants are relatively scarce. In the present work, the effects of BPA on the biomass (fresh wt and dry wt), absorptive function (activity and absorptive area), and mineral element levels in soybean (Glycine max L.) seedling roots treated with 1.5 mg L(-1) , 3.0 mg L(-1) , 6.0 mg L(-1) , 12.0 mg L(-1) , 24.0 mg L(-1) , 48.0 mg L(-1) , and 96.0 mg L(-1) BPA were investigated. Treatment with 1.5 mg L(-1) BPA increased the levels of nitrate and other mineral elements (P, K, Mg, Mn, Zn, and Mo) in the roots, whereas treatments with BPA at higher concentrations decreased the levels of these elements in the roots. All treatments with BPA caused increases in the levels of ammonium, Ca, Fe, and Cu in the roots. Moreover, treatment with 1.5 mg L(-1) BPA increased the fresh weight, dry weight, activity, and absorptive area of the roots, whereas treatments with BPA at higher concentrations decreased these indices in a dose-dependent manner. Furthermore, correlation analysis data showed that BPA affected the levels of mineral elements and absorptive function of soybean seedling roots, which may be the physiological basis of BPA action on plants.

Photosynthesis, chlorophyll fluorescence characteristics, and chlorophyll content of soybean seedlings under combined stress of bisphenol A and cadmium

Bisphenol A (BPA) is ubiquitous in the environment because of its continual application in plastics and the epoxy resin industry. Cadmium (Cd) is a highly toxic heavy metal element mainly used in smelting, electroplating, and plastic and dye manufacturing. Pollution as a result of BPA and Cd exists simultaneously in many agricultural regions. However, little information is available regarding the combined effects of BPA and Cd on plants. The combined effects of BPA and Cd on the photosynthesis, chlorophyll fluorescence, and chlorophyll content of soybean seedlings were investigated using noninvasive technology. Combined treatment with 1.5 mg/L BPA and 0.2 mg/L Cd synergistically improved the net photosynthetic rate (Pn ), initial fluorescence (F0 ), maximal photochemical efficiency (Fv /Fm ), effective quantum yield of photosystem II (ΦPSII ), photosynthetic electron transport rate (ETR), and chlorophyll content. Combined treatment with 1.5 mg/L BPA and 3.0 mg/L Cd increased the F0 and decreased the Pn , Fv /Fm , ΦPSII , and ETR, whereas BPA and Cd exhibited an antagonistic effect. Furthermore, combined treatment with 17.2/50.0 mg/L BPA and 3.0/10.0 mg/L Cd synergistically decreased the Pn , Fv /Fm , ΦPSII , ETR, and chlorophyll content, although it increased the F0 . Finally, the effects of BPA and Cd on photosynthesis, chlorophyll fluorescence, and chlorophyll content ceased when BPA stress was stopped.

Combined effects of bisphenol A and cadmium on growth and nitrate assimilation of soybean seedling roots

Bisphenol A (BPA) and cadmium (Cd) pollution exist simultaneously in many regions. However, little information is available regarding the combined effects of BPA and Cd pollution on plants. Plant roots are in direct contact with the soil, which is an important compartment of BPA and Cd. In the present study, the effects of combined BPA and Cd pollution on soybean seedling roots were evaluated in pot experiments. Combined treatment with BPA and Cd at low concentrations (1.5 mg/kg BPA and 0.2 mg/kg Cd) improved soybean seedling root growth. However, other combined BPA and Cd treatments, including combined treatment with BPA (Cd) at the low concentration and Cd (BPA) at the high concentration as well as combined treatment with BPA and Cd at the high concentration, inhibited soybean seedling root growth. The improvement or inhibition of soybean seedling root growth was greater in the combined BPA and Cd treatments than in single treatments. The effects of the combined BPA and Cd treatments on root growth resulted from changes in nitrate assimilation. In addition, the combined effects of BPA and Cd on the nitrate and ammonium contents in roots are discussed. The present research provides a basic understanding of the combined effects of BPA and Cd pollution on plant roots.

Effects of bisphenol A on the microtubule arrays in root meristematic cells of Pisum sativum L

Bisphenol A (BPA), a widely used chemical in the plastics industry that displays weak oestrogenic properties, is an emerging environmental pollutant, potentially harmful to living organisms. The presumed cytotoxicity of BPA to plant cells has been poorly studied. To understand how BPA might influence plant cell division and affect the underlying cytoskeleton, the effects of BPA on the microtubule (MT) arrays of meristematic root-tip cells of Pisum sativum L. were investigated. Root tips of young seedlings were exposed to 20, 50 and 100mg/L BPA for 1, 3, 6, 12 and 24h. The effects of each treatment were determined by means of confocal laser scanning microscopy after immunolabelling of tubulin and counterstaining of DNA, and by use of light and transmission electron microscopy. It was found that BPA affected normal chromosome segregation, hampered the completion of cytokinesis and deranged interphase and mitotic MT arrays. BPA effects were dependent on the stage of each cell at the time of BPA entrance. Moreover, BPA induced the formation of macrotubules with a mean diameter of 32 ± 0.14 nm, compared with 23 ± 0.70 nm for the MT arrays in untreated cells. Finally, all MT arrays and macrotubules were depolymerised upon longer treatment. Taken together, the data suggest that BPA exerts acute anti-mitotic effects on meristematic root-tip cells of P. sativum, MT arrays constitute a primary sub-cellular target of BPA toxicity, and the manifested chromosomal abnormalities could be attributed to the disruption of the MT cytoskeleton.

The presence and activity of progesterone in the plant kingdom

Steroids are present in living organisms as one of the most essential groups of compounds. Continuous research has led to new discoveries and the revision of existing information concerning the occurrence and the role of steroids, both in animals and plants. This article will focus on reviewing the literature studying progesterone in the plant kingdom, including its discovery, its occurrence in different plant species as well as its biological activity and molecular basis of action. This review will present and discuss the current data in addition to introducing potential directions for further research on the subject of progesterone in plants.

Reactive oxygen species are involved in pollen tube initiation in kiwifruit

The role of reactive oxygen species (ROS) during pollen tube growth has been well established, but its involvement in the early germination stage is poorly understood. ROS production has been reported in germinating tobacco pollen, but evidence for a clear correlation between ROS and germination success remains elusive. Here, we show that ROS are involved in germination and pollen tube formation in kiwifruit. Using labelling with dihydrofluorescein diacetate (H(2) FDA) and nitroblue tetrazolium (NBT), endogenous ROS were detected immediately following pollen rehydration and during the lag phase preceding pollen tube emergence. Furthermore, extracellular H(2) O(2) was found to accumulate, beginning a few minutes after pollen suspension in liquid medium. ROS production was essential for kiwifruit pollen performance, since in the presence of compounds acting as superoxide dismutase/catalase mimic (Mn-5,10,15,20-tetrakis(1-methyl-4-pyridyl)21H,23H-porphin, Mn-TMPP) or as NADPH oxidase inhibitor (diphenyleneiodonium chloride, DPI), ROS levels were reduced and pollen tube emergence was severely or completely inhibited. Moreover, ROS production was substantially decreased in the absence of calcium, and by chromium and bisphenol A, which inhibit germination in kiwifruit. Peroxidase activity was cytochemically revealed after rehydration and during germination. In parallel, superoxide dismutase enzymes, particularly the Cu/Zn-dependent subtype - which function as superoxide radical scavengers - were detected by immunoblotting and by an in-gel activity assay in kiwifruit pollen, suggesting that ROS levels may be tightly regulated. Timing of ROS appearance, early localisation at the germination aperture and strict requirement for germination clearly suggest an important role for ROS in pollen grain activation and pollen tube initiation.

Into the world of steroids: a biochemical "keep in touch" in plants and animals

Evolution of steroids such as sex hormones and ecdysteroids occurred independently in animal and plant kingdoms. Plants use phytoecdysteroids (PEs) to control defence interactions with some predators; furthermore, PEs can exert beneficial influence on many aspects of mammalian metabolism. Endocrine disrupting compounds such as the estrogen agonist bisphenol A (BPA) are widespread in the environment, posing a potential hormonal risk to animals and plants. Adverse BPA effects on reproductive development and function are coupled with other toxic effects. BPA bioremediation techniques could be developed by exploiting some tolerant plant species.