Paraquat exposure delays stem/progenitor Leydig cell regeneration in the adult rat testis

Altered Expression of Thyroid- and Calcium Ion Channels-Related Genes in Rat Testes by Short-Term Exposure to Commercial Herbicides Paraquat or 2,4-D

Exposure to pesticides such as paraquat and 2,4-dichlorophenoxyacetic acid (2,4-D) has been linked to harmful health effects, including alterations in male reproduction. Both herbicides are widely used in developing countries and have been associated with reproductive alterations, such as disruption of spermatogenesis and steroidogenesis. The thyroid axis and Ca2+-permeable ion channels play a key role in these processes, and their disruption can lead to reproductive issues and even infertility. This study evaluated the short-term effects of exposure to commercial herbicides based on paraquat and 2,4-D on gene expression in rat testes. At the molecular level, exposure to paraquat increased the expression of the thyroid hormone transporters monocarboxylate transporter 8 (Mct8) and organic anion-transporting polypeptide 1C1 (Oatp1c1) and the thyroid receptor alpha (TRα), suggesting a possible endocrine disruption. However, it did not alter the expression of the sperm-associated cation channels (CatSper1-2) or vanilloid receptor-related osmotically activated channel (Trpv4) related to sperm motility. In contrast, exposure to 2,4-D reduced the expression of the Mct10 transporter, Dio2 deiodinase, and CatSper1, which could affect both the availability of T3 in testicular cells and sperm quality, consistent with previous studies. However, 2,4-D did not affect the expression of CatSper2 or Trpv4. Deregulation of gene expression could explain the alterations in male reproductive processes reported by exposure to paraquat and 2,4-D. These thyroid hormone-related genes can serve as molecular biomarkers to assess endocrine disruption due to exposure to these herbicides, aiding in evaluating the health risks of pesticides.

Herbicide paraquat dichloride augments the expression of the c-abl-noxa-apoptotic pathway, instigating ovarian atresia in edible fish, Channa punctatus

Ovarian cells of animals undergo atresia to regulate egg numbers and their release. However, unrestrained atretic activity decreases the chances of oocyte maturity and further process, ultimately resulting in a reduced population. Edible fishes are a critical source of nutrition and it is required to regulate their population. The application of herbicides at fish production sites is a threat to their population by altering female reproductive activity. In concern to this, here, this 60-day study investigates herbicide paraquat dichloride (PD)-induced atresia in ovarian cells of Channa punctatus (C. punctatus). Further, 96-h LC50 of PD for C. punctatus was calculated as 58.40 mg/L. At the end of each exposure period, an increase in intracellular ROS in blood cells and activities of SOD and CAT in ovary tissue were observed in PD-treated fish with increasing concentration. The frequency of micronuclei in blood cells subsequently increased with the highest PD concentration. A significant (p < 0.05) increase in the relative expression of target genes was observed at the 30th and 60th day of the sampling periods in the fish treated with the highest concentration of PD. The histological study confirmed the occurrence of atretic ovary cells in PD-exposed fish. From the results it can be concluded that PD enhances the uncontrolled death of ovarian cells and has consequences of impairing the ovary health and reproductive potential of fish, hence reducing the fish population.

Effective attenuation of Paraquat induced oxidative stress and Genotoxicity in testicular germ cells by vitamin E in Caprines

Toxicological empirical research suggests that excessive utilization of paraquat, an herbicide, shows detrimental consequences on mammalian reproductive toxicity. The current study aims to study it as a reproductive toxin on the caprine testicular cells at 4- and 6-hour exposure duration. Paraquat treatment decreased the cell viability percentage and induced histological architectural alterations such as disruption of germinal epithelium, vacuolization, and pyknotic nuclei in the testis. The differential EB/AO staining also revealed an increased incidence of apoptosis after paraquat treatment at both dosages, i.e. 10 mM and 100 mM. Paraquat also induces oxidative stress, as evident via increased Malondialdehyde levels (a byproduct of lipid peroxidation) and a decline in the antioxidant capacity (FRAP). However, co-administration of Vitamin E significantly reduced the paraquat-mediated decline in cell viability percentage, histological alterations, and apoptosis incidences and generated oxidative stress, indicating its antioxidative properties against paraquat exposure. This research concludes that Vitamin E co-administration considerably reduced the toxicity of paraquat elicited in testicles, suggesting that Vitamin E may have advantageous potential in preventing the male gonadotoxicity caused by paraquat use in agriculture.

Curative effects of tectochrysin on paraquat-instigated testicular toxicity in rats: A biochemical and histopathological based study

Background

Paraquat (PQ) is a herbicide that is used globally in the agriculture sector to eradicate unwanted weeds, however it also induces significant damages in various organs of the body such as testes. Tectochrysin (TEC) is an important flavonoid that shows versatile therapeutic potentials. Currently, there is no established antidote to cure PQ-induced testicular toxicity.

Objective

The present study was conducted to evaluate the ameliorative effects of TEC against PQ prompted testicular damage.

Methods

Sprague-Dawley rats (n = 48) were used to conduct the trial. Rats were allocated in to 4 groups i.e., Control, PQ administrated group (5 mgkg-1), PQ + TEC co-administrated group (5 mgkg-1 + 2.5 mgkg-1) and TEC only administrated group (2.5 mgkg-1). The trial was conducted for 8 weeks. The activity of anti-oxidants and the levels of MDA and ROS were determined by spectrophotometric method. Steroidogenic enzymes as well as apoptotic markers expressions were evaluated by qRT-PCR. The level of hormones and inflammatory indices was quantified by enzyme-linked immunosorbent assay.

Results

PQ exposure markedly (P < 0.05) disturbed the biochemical, spermatogenic and histological profile in the rats. Nevertheless, TEC treatment considerably (P < 0.05) increased CAT, GPx GSR and SOD activity, besides decreasing MDA and ROS contents. TEC administration also increased sperm viability, count and motility. 17β-HSD, 3β-HSD, StAR and Bcl-2 expressions were also increased following TEC administration. The supplementation of TEC substantially (P < 0.05) decreased Bax, Caspase-3 expression and the levels of inflammatory markers i.e., interleukin-1β (IL-1β), interleukin-6 (IL-6), nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) activity. Additionally, the levels of plasma testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were increased following TEC supplementation. Furthermore, TEC supplementation considerably decreased sperm structural abnormalities and histomorphological damages of the testes. The mitigative role of TEC might be due to its anti-inflammatory, anti-apoptotic, androgenic and anti-oxidant potentials.

Conclusion

Taken together, it is concluded that TEC can be used as a potential candidate to treat testicular toxicity.

Ethylene dimethanesulfonate effects on gene promoter activities related to the endocrine function of immortalized Leydig cell lines R2C and MA-10

Ethylene dimethanesulfonate (EDS) is a molecule with known selective cytotoxicity on adult Leydig cells. A single intraperitoneal injection in rats but not mice, leads to male androgen deprivation and infertility. In vitro studies using rat and mouse immortalized Leydig cell lines, showed similar effects of cell death promoted by EDS in rat cells as seen in vivo, and suggest that EDS affects gene transcription, which could firstly compromise steroidogenesis before the apoptosis process. Using gene reporter assay, this study aimed to investigate EDS effects on the promoter activity of genes important for endocrine function (Star, Insl3) and response to toxic agents (Gsta3) in immortalized Leydig cell lines (rat R2C and mouse MA-10 cells), as well as identify possible EDS-responsive elements in the Star gene promoter. EDS exposure of R2C and MA-10 Leydig cells increased Gsta3 promoter activity after 4 h of treatment and decreased Insl3 promoter activity only in R2C cells after 24 h of treatment. EDS also decreased Star promoter activity in both Leydig cell lines. Using R2C cells, the EDS-responsive region in the Star promoter was located between -400 and -195 bp. This suggests that this region and the associated transcription factors, which include MEF2, might be targeted by EDS. Additional somatic gonadal cell lines expressing Star were used and EDS did not affect Star promoter activity in DC3 granulosa cells while Star promoter activity was increased in MSC-1 Sertoli cells after 24 h of treatment. This study contributes to the knowledge regarding the mechanism of EDS action in Leydig cells, and in other gonadal cell lineages, and brings new light regarding the rats and mice differential susceptibility to EDS effects, in addition to providing new avenues for experimental approaches to better understand Leydig cell function and dynamics in different rodent species.

Melatonin Ameliorates Diquat-Induced Testicular Toxicity via Reducing Oxidative Stress, Inhibiting Apoptosis, and Maintaining the Integrity of Blood-Testis Barrier in Mice

Diquat is a fast, potent, and widely used bipyridine herbicide in agriculture and it induces oxidative stress in several animal models. However, its genotoxic effects on the male reproductive system remain unclear. Melatonin is an effective free-radical scavenger, which has antioxidant and anti-apoptotic properties and can protect the testes against oxidative damage. This study aimed to investigate the therapeutic effects of melatonin on diquat-induced testicular injury in mice. The results showed melatonin treatment alleviated diquat-induced testicular injury, including inhibited spermatogenesis, increased sperm malformations, declined testosterone level and decreased fertility. Specifically, melatonin therapy countered diquat-induced oxidative stress by increasing production of the antioxidant enzymes GPX1 and SOD1. Melatonin treatment also attenuated diquat-induced spermatogonia apoptosis in vivo and in vitro by modulating the expression of apoptosis-related proteins, including P53, Cleaved-Caspase3, and Bax/Bcl2. Moreover, melatonin restored the blood-testicular barrier by promoting the expression of Sertoli cell junction proteins and maintaining the ordered distribution of ZO-1. These findings indicate that melatonin protects the testes against diquat-induced damage by reducing oxidative stress, inhibiting apoptosis, and maintaining the integrity of the blood-testis barrier in mice. This study provides a theoretical basis for further research to protect male reproductive health from agricultural pesticides.

The effects and molecular mechanism of heat stress on spermatogenesis and the mitigation measures

Under normal conditions, to achieve optimal spermatogenesis, the temperature of the testes should be 2-6 °C lower than body temperature. Cryptorchidism is one of the common pathogenic factors of male infertility. The increase of testicular temperature in male cryptorchidism patients leads to the disorder of body regulation and balance, induces the oxidative stress response of germ cells, destroys the integrity of sperm DNA, yields morphologically abnormal sperm, and leads to excessive apoptosis of germ cells. These physiological changes in the body can reduce sperm fertility and lead to male infertility. This paper describes the factors causing testicular heat stress, including lifestyle and behavioral factors, occupational and environmental factors (external factors), and clinical factors caused by pathological conditions (internal factors). Studies have shown that wearing tight pants or an inappropriate posture when sitting for a long time in daily life, and an increase in ambient temperature caused by different seasons or in different areas, can cause an increase in testicular temperature, induces testicular oxidative stress response, and reduce male fertility. The occurrence of cryptorchidism causes pathological changes within the testis and sperm, such as increased germ cell apoptosis, DNA damage in sperm cells, changes in gene expression, increase in chromosome aneuploidy, and changes in Na⁺/K⁺-ATPase activity, etc. At the end of the article, we list some substances that can relieve oxidative stress in tissues, such as trigonelline, melatonin, R. apetalus, and angelica powder. These substances can protect testicular tissue and relieve the damage caused by excessive oxidative stress.

Understanding paraquat resistance mechanisms in Arabidopsis thaliana to facilitate the development of paraquat-resistant crops

Paraquat (PQ) is the third most used broad-spectrum nonselective herbicide around the globe after glyphosate and glufosinate. Repeated usage and overreliance on this herbicide have resulted in the emergence of PQ-resistant weeds that are a potential hazard to agriculture. It is generally believed that PQ resistance in weeds is due to increased sequestration of the herbicide and its decreased translocation to the target site, as well as an enhanced ability to scavenge reactive oxygen species. However, little is known about the genetic bases and molecular mechanisms of PQ resistance in weeds, and hence no PQ-resistant crops have been developed to date. Forward genetics of the model plant Arabidopsis thaliana has advanced our understanding of the molecular mechanisms of PQ resistance. This review focuses on PQ resistance loci and resistance mechanisms revealed in Arabidopsis and examines the possibility of developing PQ-resistant crops using the elucidated mechanisms.

Flurochloridone Induced Cell Apoptosis via ER Stress and eIF2α-ATF4/ATF6-CHOP-Bim/Bax Signaling Pathways in Mouse TM4 Sertoli Cells

Flurochloridone (FLC), as a novel herbicide, has been widely used in many countries since 1980s. Current studies have shown that FLC has toxic effects on male reproduction and its target organ is testis, while the underlying mechanism is still unknown. Mouse testis Sertoli cell line TM4 cells were used as an in vitro model and treated with FLC at different doses (40, 80, 160 μM) for different times (6, 12, 24 h). Cell viability, cytotoxicity and apoptotic cells were detected by CCK-8 assay, LDH leakage assay and flow cytometry. The protein levels of GRP78, phosphorylated-eIF2α, ATF4, ATF6, CHOP, Bim and Bax were observed by Western Blot and Immunofluorescence staining. FLC inhibited cell viability and induced cytotoxicity in dose-dependent way in TM4 cells. The percentage of apoptotic cells were 6.2% ± 0.6%, 7.3% ± 0.3%, 9.8% ± 0.4%, 13.2% ± 0.2%, respectively. The expression levels of ER stress and UPR related proteins were activated over dose. Meanwhile, the pro-apoptotic proteins (Bim and Bax) were also up-regulated in dose-dependent. After pretreated with ISRIB, the inhibitor of eIF2α phosphorylation, the elevated expression of GRP78, phosphorylated-eIF2α, ATF4, ATF6, CHOP and Bim was down to normal level accordingly. In conclusion, FLC induced apoptosis in TM4 cells mediated by UPR signaling pathways.

Use of Lens culinaris Med test as environmental bioindicator to identify the cytogenotoxic effect of paraquat pesticide

Paraquat is the most widely used herbicide and the third most sold pesticide in the world, applied in more than 120 countries despite being banned in the European Union. It is a risk to ecosystems. The genotoxic effect of paraquat was evaluated using the Lens culinaris test. L. culinaris seeds were subjected to 6 concentrations of paraquat (0.1, 0.5, 1, 1.5, 1.5, 2, and 3 ppm) plus a control (distilled water). During 72 h, root development was measured every 24 h. After 3 days, root apices were analyzed to obtain the inhibition of the mitotic index, as well as the type and rate of chromosomal abnormalities present. A decrease in root growth of more than 50% (72 h of exposure) and an inhibition of the mitotic index of 2.9 times in the treatment with 3 ppm compared to the control were observed. The 2 ppm concentration presented all the anomalies found with a frequency of 84 ± 2.5 of micronuclei, 106 ± 3.5 of nuclear lesions, 14 ± 4.7 of nucleus absence, 8 ± 2.7 of telophase bridges, 7 ± 2.7 of binucleated cells, among others. It is also recommended to establish comparisons of L. culinaris with multiple biomarkers since it is presented as a practical and economic alternative.

Protective Role of 4-(4-Hydroxy-3-methoxyphenyl)-2-Butanone on Prostatic Cells Hyperplasia of Rats and Human, 5α-reductase Inhibition Pathway

BACKGROUND

Prostate gland is an exocrine gland that could be affected by various pathological conditions. Benign prostatic hyperplasia (BPH) is an age-dependent medical condition caused by increased activity of 5α-reductase enzyme (5α-R). Medical treatment by finasteride is considered during treatment, but it has unavoidable side effects. Hence, there is an increasing need to use natural ingredients for BPH treatment. Gingerol oil (ginger extract) is transferred by heating into zingerone. Recent studies reported the effect of zingerone on prostate cancer cells.

AIMS AND OBJECTIVES

The aim of the present research is to investigate the protective effect of zingerone against BPH.

MATERIALS AND METHODS

Sixty male Albino Wistar rats were divided into three groups: control group, prostatic hyperplasia group treated with saline, and prostatic hyperplasia group treated with zingerone (PH-Z-G). At day 28, all rats were sacrificed, epididymis and prostate samples were collected for histopathological examination and Western blotting for androgen receptors (ARs) proteins and steroid 5 alpha-reductase 1 (SRD5A1). Human RWPE-1 prostatic cell line was assessed for viability and cycle after treated with zingerone 500 μg/day for 10 days.

RESULTS

PH-S group showed significant (P < 0.05) thickening of connective tissue septa associated with narrowing of acinar lumen. PH-Z group showed regain of the normal histological feature. SRD5A1 and AR expression was significantly (P < 0.05) reduced in PH-Z group in comparison with PH-S group. Cell line proliferation was significantly reduced after application of zingerone with G2/M cell cycle arrest.

CONCLUSION

Our results showed that natural herbal zingerone decreased the prostatic tissue levels of (5α reductase and AR) in rat BPH model, which could be a promising herbal medicine for BPH treatment. Further human clinical trials are required.

Effect of paraquat on cytotoxicity involved in oxidative stress and inflammatory reaction: A review of mechanisms and ecological implications

Paraquat (PQ) is a cheap and an effective herbicide, which is widely being used worldwide to remove weeds in cultivated crop fields. However, it can cause soil and water pollution, and pose serious harm to the environment and organisms. Several countries have started to limit or prohibit the use of PQ because of the increasing number of human deaths. Its toxicity can damage the organisms with a multi-target mechanism, which has not been fully understood yet. That is why it is hard to treat as well. The current research on PQ focuses on its targeted organ, the lungs, in which PQ mostly trigger pulmonary fibrosis. While there is a lack of systematic research, there are few studies published discussing its toxic effects at systematic level. This review summarizes the major damages caused by PQ in different organisms and partial mechanisms by which it causes these damages. For this purpose, we consulted several research articles that studied the toxicity of PQ in various tissues. We also listed some drugs that can be used to alleviate the toxicity of PQ. However, at present, the effectiveness of these drugs is still being explored in animal experiments and the study of their mechanism will also help in understanding the poisoning mechanism of PQ, which will ultimately lead to effective treatment in future.

Mechanisms of deleterious effects of some pesticide exposure on pigs

The increase in the size of the global population increases the food and energy demand, making the use of pesticides in agricultural and livestock industries unavoidable. Exposure to pesticides can be toxic to the non-target species, such as humans, wildlife, and livestock, in addition to the target organisms. Various chemicals are used in the livestock industry to control harmful organisms, such as insects, weeds, and parasites. Pigs are one of the most important food sources for humans. In addition, pigs can be used as promising models for assessing the risk of absorption of environmental pollutants through the skin and oral exposure since they are physiologically similar to humans. Exposure to numerous environmental pollutants, such as mycotoxins, persistent organic pollutants, and heavy metals, has been reported to adversely affect growth, fertility, and endocrine homeostasis in pigs. Various pesticides have been observed in porcine tissues, blood, urine, and processed foods; however, there is a lack of comprehensive understanding of their effects on porcine health. This review provides a comprehensive description of the characteristics of pesticides that pigs can be exposed to and how their exposure affects porcine reproductive function, intestinal health, and endocrine homeostasis in vivo and in vitro.

Paraquat Reduces the Female Fertility by Impairing the Oocyte Maturation in Mice

Paraquat (PQ) is a widely used non-selective and oxidizing herbicide in farmland, orchards, flower nursery, and grassland. Overuse of PQ will accumulate in the body and affect the reproduction in mammals. In this study, we found that PQ could reduce the female fertility by oral administration for 21 days in mice. PQ exposure could impair the nuclear maturation by perturbing the spindle assembly and kinetochore–microtubule attachment to cause the misaligned chromosomes during meiosis. In the meantime, PQ exposure disturbed the mitochondrial distribution and enhanced the level of reactive oxygen species and early apoptosis, which thereby deteriorated the early embryo development. Also, PQ administration could cause some changes in epigenetic modifications such as the level of H3K9me2 and H3K27me3. Therefore, PQ administration reduces the female fertility by impairing the nuclear and cytoplasmic maturation of oocytes in mice.

Cisatracurium stimulates testosterone synthesis in rat and mouse Leydig cells via nicotinic acetylcholine receptor

As a cis-acting non-depolarizing neuromuscular blocker through a nicotinic acetylcholine receptor (nAChR), cisatracurium (CAC) is widely used in anaesthesia and intensive care units. nAChR may be present on Leydig cells to mediate the action of CAC. Here, by Western blotting, immunohistochemistry and immunofluorescence, we identified that CHRNA4 (a subunit of nAChR) exists only on rat adult Leydig cells. We studied the effect of CAC on the synthesis of testosterone in rat adult Leydig cells and mouse MLTC-1 tumour cells. Rat Leydig cells and MLTC-1 cells were treated with CAC (5, 10 and 50 μmol/L) or nAChR agonists (50 μmol/L nicotine or 50 μmol/L lobeline) for 12 hours, respectively. We found that CAC significantly increased testosterone output in rat Leydig cells and mouse MLTC-1 cells at 5 μmol/L and higher concentrations. However, nicotine and lobeline inhibited testosterone synthesis. CAC increased intracellular cAMP levels, and nicotine and lobeline reversed this change in rat Leydig cells. CAC may increase testosterone synthesis in rat Leydig cells and mouse MLTC-1 cells by up-regulating the expression of Lhcgr and Star. Up-regulation of Scarb1 and Hsd3b1 expression by CAC was also observed in rat Leydig cells. In addition to cAMP signal transduction, CAC can induce ERK1/2 phosphorylation in rat Leydig cells. In conclusion, CAC binds to nAChR on Leydig cells, and activates cAMP and ERK1/2 phosphorylation, thereby up-regulating the expression of key genes and proteins in the steroidogenic cascade, resulting in increased testosterone synthesis in Leydig cells.

Cellulose Nanocrystals/Graphene Hybrids-A Promising New Class of Materials for Advanced Applications

With the growth of global fossil-based resource consumption and the environmental concern, there is an urgent need to develop sustainable and environmentally friendly materials, which exhibit promising properties and could maintain an acceptable level of performance to substitute the petroleum-based ones. As elite nanomaterials, cellulose nanocrystals (CNC) derived from natural renewable resources, exhibit excellent physicochemical properties, biodegradability and biocompatibility and have attracted tremendous interest nowadays. Their combination with other nanomaterials such as graphene-based materials (GNM) has been revealed to be useful and generated new hybrid materials with fascinating physicochemical characteristics and performances. In this context, the review presented herein describes the quickly growing field of a new emerging generation of CNC/GNM hybrids, with a focus on strategies for their preparation and most relevant achievements. These hybrids showed great promise in a wide range of applications such as separation, energy storage, electronic, optic, biomedical, catalysis and food packaging. Some basic concepts and general background on the preparation of CNC and GNM as well as their key features are provided ahead.

Paraquat exposure delays late-stage Leydig cell differentiation in rats during puberty

Paraquat is a fast and non-selective herbicide that is widely used in crop cultivation and conservation tillage systems. Animal experiments have shown that paraquat decreases sperm quality and testicular organ coefficient, but its effects on the development of Leydig cells remain unclear. The objective of the current study was to investigate the effects of paraquat exposure on the Leydig cell development in rats during puberty. Twenty-eight male 35-day-old Sprague-Dawley rats were divided into 4 groups: 0, 0.5, 2.0, and 8 mg kg^-1 d^-1 paraquat. Paraquat was gavaged for 10 d. Adult Leydig cells were isolated and treated with paraquat for 24 h. Paraquat in vivo significantly decreased body and testis weights at 8 mg kg^-1 and lowered serum testosterone levels at 2 and 8 mg kg^-1 without affecting the levels of serum luteinizing hormone and follicle-stimulating hormone. Paraquat did not alter Leydig cell number and PCNA labeling index. Real-time PCR showed that paraquat down-regulated the expression of Lhcgr, Scarb1, Cyp11a1, Cyp17a1, and Hsd17b3 genes and their proteins at 2 or 8 mg kg^-1, while it up-regulated the expression of Srd5a1 at 8 mg kg^-1. Paraquat increased ROS and decreased testosterone production by Leydig cells at 1 and 10 μM after in vitro 24-h exposure. Vitamin E (40 μg/ml) reversed paraquat-induced ROS and suppression of testosterone synthesis in vitro. In conclusion, paraquat directly delays Leydig cell differentiation to block testosterone synthesis via down-regulating the expression of critical testosterone synthesis-related genes and up-regulating the expression of testosterone metabolic enzyme (Srd5a1) gene and possibly via increasing ROS production.