A comprehensive evaluation of the testicular toxicity of dichlorvos in Wistar rats

De novo synthesis of a novel hapten and development of a monoclonal antibody-based immunoassay for the detection of dichlorvos and trichlorfon

The absence of high-affinity antibodies has hindered the development of satisfactory immunoassays for dichlorvos (DDVP) and trichlorfon (TCP), two highly toxic organophosphorus pesticides. Herein, the de novo synthesis of a novel anti-DDVP hapten was introduced. Subsequently, a specific anti-DDVP monoclonal antibody (Mab) was produced with satisfying affinity to DDVP (IC50: 12.4 ng mL-1). This Mab was highly specific to DDVP, and TCP could readily convert into DDVP under mild alkaline conditions. Leveraging this insight, an indirect competitive ELISA was successfully developed for simultaneous detection of DDVP and TCP. The limit of detection in rice, cabbage and apple for DDVP /TCP was found to be 12.1/14.6 μg kg-1, 7.3/8.8 μg kg-1 and 6.9/8.3 μg kg-1, respectively. This study not only provides an effective strategy for producing a high-quality anti-DDVP Mab but also affords a reliable and cost-effective tool suitable for high-throughput detection of DDVP and TCP in food samples.

L-arginine attenuates dichlorvos-induced testicular toxicity in male Wistar rats by suppressing oxidative stress-dependent activation of caspase 3-mediated apoptosis

BACKGROUND

The continuous use of pesticides, such as dichlorvos, is a common agricultural and domestic practice. However, it is associated with shortfalls like testicular toxicity through the induction of oxidative stress-mediated signaling. On the other hand, L-arginine, a precursor of nitric oxide, has been reported to exert antioxidant activities and thus may attenuate dichlorvos-induced testicular toxicity.

AIM

Hence, this study was designed to evaluate the effect of L-arginine treatment on dichlorvos-induced testicular toxicity.

MATERIALS AND METHODS

Forty male Wistar rats were randomly assigned into four equal groups. The control rats were administered 0.5 mL of distilled water, dichlorvos- (DDVP-) treated rats were exposed to DDVP via inhalation for 15 min, DDVP + L-arginine-treated rats were exposed to DDVP and also received 100 mg/kg b.w/day, while L-arginine-treated rats received 100 mg/kg b.w/day.

RESULTS

DDVP exposure significantly reduced testicular nitric oxide, relative testicular weight, lowered sperm count, viability, and motility, and suppressed serum FSH, LH, and testosterone levels. These findings were associated with a rise in testicular malondialdehyde, TNF-α, IL-6, and 8OHdG levels and caspase 3 activities, and a reduction in GSH and superoxide dismutase. Additionally, on histopathological examination, DDVP was observed to reduce mature sperm cells in the seminiferous tubular lumen and induce focal vascular congestion in the interstitial space. Nonetheless, L-arginine treatment significantly attenuated DDVP-induced biochemical and histological alterations.

CONCLUSION

This study showed that L-arginine attenuated testicular toxicity by improving epididymal sperm variables and male sex hormones by suppressing oxidative stress, inflammation, and apoptosis in DDVP-exposed rats.

Rats' testicular toxicity induced by bisphenol A is lessened by crocin via an antiapoptotic mechanism and bumped P-glycoprotein expression

Bisphenol A (BPA) engenders testicular toxicity via hydroxyl free radical genesis in rat striatum and depletion of the endogenous antioxidants in the epididymal sperms. The multi-drug resistance efflux carrier; P-glycoprotein (P-gp) expel the BPA from the testis and is responsible for the testicular protection through the deactivation of numerous xenobiotics. In our study, we investigated whether the BPA-induced testicular toxicity could be circumvented through administration of an antioxidant; crocin (Cr). Implication of P-gp expression was also investigated. Rats administered BPA (10 mg/kg b.w. orally for 14 days), dropped the body weight, testes/body weight ratio, total protein content, testosterone, follicle stimulating hormone, luteinizing hormone, and sperm motility & count, total antioxidant status, glutathione content and antioxidant enzymes (superoxide dismutase and catalase), concomitant with the elevation of the percentage abnormal sperm morphology, as well as testicular lipid peroxides and nitrite/nitrate levels. Histopathological examination showed spermatogenesis disorders after the BPA rats exposure. The immunohistochemical study showed up-regulation of the P-gp as evident by increasing immunoreactivity in interstitial cells, with positive localization in some spermatogonia cells. The BPA-treated rats showed positive immunoreactivity against caspase-3. The co-intake of Cr (200 mg/kg b.w./day, i.p. 14 days) along with the BPA, significantly ameliorated all the mentioned parameters, boosted histopathological image, fell the caspase-3 up-regulation, and perched the P-gp expression. We showed that, Cr promotes P-gp as an approach to nurture the testicles against the BPA toxicity. In conclusion; Cr lessens the oxidative stress conditions to safeguard rats from the BPA-induced testicular toxicity and sex hormones abnormalities, reducing apoptosis and up-regulating P-gp.

Cellular metabolism and health impacts of dichlorvos: Occurrence, detection, prevention, and remedial strategies-A review

Dichlorvos (2,2-Dichlorovinyl dimethyl phosphate, [DDVP]) belongs to the class of organophosphates and is widely used as an insecticide in agriculture farming and post-harvest storage units. Extensive research has been conducted to assess the factors responsible for the presence of DDVP in terrestrial and aquatic ecosystems, as well as the entire food chain. Numerous studies have demonstrated the presence of DDVP metabolites in the food chain and their toxicity to mammals. These studies emphasize that both immediate and chronic exposure to DDVP can disrupt the host's homeostasis, leading to multi-organ damage. Furthermore, as a potent carcinogen, DDVP can harm aquatic systems. Therefore, understanding the contamination of DDVP and its toxicological effects on both plants and mammals is vital for minimizing potential risks and enhancing safety in the future. This review aimed to comprehensively consolidate information about the distribution, ecological effects, and health impacts of DDVP, as well as its metabolism, detection, prevention, and remediation strategies. In summary, this study observes the distribution of DDVP contaminations in vegetables and fruits, resulting in significant toxicity to humans. Although several detection and bioremediation strategies are emerging, the improper application of DDVP and the alarming level of DDVP contamination in foods lead to human toxicity that requires attention.

Salvia officinalis restores semen quality and testicular functionality in cadmium-intoxicated male rats

The present study investigated the potential ability of Salvia officinalis, one of the oldest medicinal plants, to protect male rats against cadmium reproductive toxicity. Twenty-eight healthy male rats were randomly allocated into four groups (n = 7); control, Salvia-extract treated group, cadmium treated group and a group treated with both Cd and Salvia. Administration of cadmium reduced the relative testis to body weight and significantly affected sperm parameters by decreasing motility, viability, count and increasing morphological aberrations. Comet assay was used to detect DNA fragmentation in sperms of the rats exposed to Cd. Serum levels of testosterone T, follicle stimulating hormone FSH, and luteinizing hormone LH were significantly decreased. The biochemical analysis of testicular tissue showed a significant rise in Malondialdehyde MDA level coupled with a decrease in the activity of antioxidant enzymes (superoxide dismutase SOD, glutathione peroxidase GPx and catalase CAT). The histological examination of testis sections after Cd administration revealed severe degeneration of spermatogenic cells. Seminiferous tubules were filled with homogenous eosinophilic fluid associated with atrophy of other seminiferous tubules. Co-treatment with the Salvia officinalis extract restored the oxidative enzymes activities and decreased the formation of lipid peroxidation byproduct, which in turn ameliorated the effect of Cd on sperm parameters, DNA damage and testis histopathology. Taken together, it can be concluded that the synergistic antioxidant and radical savaging activities of Salvia officinalis prevented the effect of Cd on semen quality, sperm DNA damage, along with the oxidative stress and histological abnormalities in the testis tissues.

Impact of organophosphate pesticides exposure on human semen parameters and testosterone: a systematic review and meta-analysis

Background

Organophosphate (OP) pesticides have been associated with a decline in semen quality, although there are still considerable arguments about the magnitude of the association.

Objective

This study provides a systematic review and meta-analysis of the impacts of OP pesticides on semen quality and male reproductive hormones.

Methods

This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocols. Strategic search was conducted using combined text words as search terms. The eligibility criteria were developed based on Population, Exposure, Comparator, Outcome, and Study designs (PECOS) framework. Relevant data were extracted, risk of bias was evaluated by The Office of Health Assessment and Translation (OHAT) tool, and certainty of evidence was assessed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group guidelines. Quantitative meta-analysis was performed by using Review Manager.

Results

A total of 766 male subjects (349 exposed to OP pesticides and 417 unexposed controls) were included in the meta-analysis. There was no significant difference in the ejaculate volume, seminal fluid volume, sperm multiple anomaly index, sperm, and leukocytes levels of the OP-exposed subjects compared to the control. In addition, OP pesticides exposure did not significantly affect serum concentrations of FSH, LH, and testosterone in subjects who were exposed to OP pesticides compared to their unexposed counterparts. However, we found a significant reduction in the sperm count, sperm concentration, progressive sperm motility, total sperm motility, and normal sperm morphology of OP pesticides-exposed subjects compared to the unexposed subjects. However, after subtype and sensitivity analyses, exposure to OP pesticides did not reduce sperm count. Also, after sensitivity analysis, OP pesticides exposure did not alter progressive sperm motility.

Conclusion

This study demonstrates that OP pesticides exposure reduced sperm count, concentration, total and progressive motility, and normal sperm morphology, possibly via a testosterone-independent mechanism.

Effects of Dichlorvos on cardiac cells: Toxicity and molecular mechanism of action

In this study we aimed to understand the underlying mechanism of Dichlorvos-induced toxicity in cardiac cells. For this end, cells were treated by 170 μM of Dichlorvos (DDVP) (corresponding to the IC50) and molecular events were monitored by flow cytometry and western blotting. We have first demonstrated that cell exposure to DDVP for 24 h induced cell death by necroptosis. In fact, cell treatment with DDVP upregulated RIP1 expression and we have shown that chemical inhibition of RIP1 kinase activity by necrostatin-1 (Nec-1) greatly prevented from the induced cell death. Besides, we have demonstrated that, while there was no observed cell death following short exposure to DDVP (6 h), autophagy was enhanced, as proven by the increase in the level of both Beclin-1 and LC3-II and the accumulation of the CytoID® autophagy detection probe. Besides, when autophagy was inhibited by chloroquine (CQ) the percentage of necroptosis was significantly increased, suggesting that autophagy acts to protect cardiac cells against the toxicity induced by this pesticide. Concurrently, we have shown that the inhibition of the deacetylase sirtuin 1 (SIRT1) by EX527 or its knockdown by siRNA significantly increased DDVP-induced necroptosis, whereas when SIRT1 was activated by resveratrol (RSV) a significant decrease in DDVP-induced cell death was observed. In addition, we revealed that when the autophagy was inhibited by CQ, we can't reveal the protective effect of RSV anymore. Altogether, these results suggest that activation of SIRT1 protects cardiac cells from the toxicity of DDVP through an autophagy-dependent pathway.

Dichlorvos and Paraquat induced avoidance responses in tadpoles (Amietophrynus regularis reuss, 1833) and their contribution to population decline

Pesticides notwithstanding their benefits in agriculture pose threats to non-target fauna such as amphibians. This study examined the avoidance responses of tadpoles of the African common toad, <i>Amietophrynus regularis</i>, exposed to Dichlorvos and Paraquat under a non-forced multi-compartmented exposure system (NFS) and estimated the Population Immediate Decline (PID) by integrating avoidance and lethal responses. The NFS was designed to allow the free movement of tadpoles across six compartments in order to elucidate the ability of aquatic organisms to detect and potentially avoid contaminated environments at will. The tadpoles (n=3 per compartment/concentration; 18 per system) were exposed to gradients of Dichlorvos (0, 0.3, 0.5, 0.7, 1.0 and 2.0 mg/L) and Paraquat (0, 1.0, 5.0, 10.0, 15.0, and 20.0 mg/L) in quadruplicates with their distribution recorded every 20 mins for 3 h. 48 h acute toxicity tests under forced exposure system (FS) was performed using the same range of concentrations. Acute toxicity (48 h) response in the FS tests was dose dependent with LC₅₀ values of 0.79 mg/L and 6.46 mg/L recorded for Dichlorvos and Paraquat, respectively. The mean percentage distribution of tadpoles recorded for Dichlorvos and Paraquat was about 11% and 0% in the highest concentrations (2.0 and 20.0 mg/L) to 58% and 69% in compartments with no contaminants (control), respectively. PID was primarily driven by avoidance responses rather than mortality. These findings are of conservation interest as it elucidates the potential of both pesticides to impair local distribution of amphibians and cause biodiversity loss.

Adverse effect of rheumatoid arthritis on male Wistar rat's fertility: protective role of Costus extract

Rheumatoid arthritis (RA) is a systemic autoimmune complaint. Advanced treatments resort to the traditional herbal therapy. The aim of this study is to assess the protective effect of Costus extract on the fertility of male rats with Freund's adjuvant-induced rheumatoid arthritis. Thirty male adult Wistar rats (190-200 g) were divided into six groups. They were subdivided into three groups; group I was the control group that received distilled water, and groups II and III received two various doses of Costus extract (200 and 400 mg/kg, respectively) for 60 days. Another three groups were subjected to RA induction via Freund's adjuvant. Rats were injected a dose of 0.1 ml of Freund's complete adjuvant (FCA) in the planter area of the left hind paw and then subdivided into 3 groups. Group I of RA-induced rats were given distilled water. The other two groups were given orally (200 and 400 mg/kg dosage of extract, respectively) from the 2nd day of RA induction for 60 days. Sex organ relative weight, sperm concentration assay, testicular histopathology and immunohistochemistry of androgen receptors, TNF α, and BAX protein were determined. The results showed that RA caused a significant decrease in the relative weight of sex organs and sperm count, which were relatively improved by doses of Costus (200, 400 mg/kg). RA induction caused testicular degeneration which markedly enhanced with Costus treatment as shown in histopathological sections. RA caused a reduction in %IHC of androgen receptors and increased expression level of both TNF α and BAX protein. Using IHC, it was revealed that RA caused a reduction in the expression level of androgen receptors and an increase in the expression of both TNF α and BAX protein. We can conclude that Costus speciosus had a potentially valuable role in improving fertility disorders caused by RA.

Testicular deficiency associated with exposure to cypermethrin, imidacloprid, and chlorpyrifos in adult rats

The testicular deficiency associated with exposure to three widely used insecticides in Egyptian agriculture was evaluated. Animals were orally treated with sub-lethal dose (1/50 of the oral LD₅₀) of cypermethrin (CYP), imidacloprid (IMC), and chlorpyrifos (CPF) at 5, 9 and 1.9 mg/kg/day, respectively, five times a week for one month. The CYP, IMC, and CPF exposure resulted in a significant decline in animal body weight, sperm count, motility, normality, and viability with increased head and tail deformities. Significant reduction in serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), testis superoxide dismutase (SOD), and reduced glutathione (GSH) levels. In contrast, catalase (CAT), lipid peroxidation (LPO), and protein carbonyl content (PCC) levels were significantly stimulated. Jointly, obtained results were confirmed by microscopic examination of testis sections. The present data concluded that the CYP, IMC, and CPF have a public health impact and violently interferes with male rat reproductive system.

Chlorella vulgaris or Spirulina platensis mitigate lead acetate-induced testicular oxidative stress and apoptosis with regard to androgen receptor expression in rats

The current research was constructed to throw the light on the protective possibility of Chlorella vulgaris (C. vulgaris) and Spirulina platensis (S. platensis) against lead acetate-promoted testicular dysfunction in male rats. Forty rats were classified into four groups: (i) control, (ii) rats received lead acetate (30 mg/kg bw), (iii) rats concomitantly received lead acetate and C. vulgaris (300 mg/kg bw), (vi) rats were simultaneously treated with lead acetate and S. platensis (300 mg/kg bw) via oral gavage for 8 weeks. Lead acetate promoted testicular injury as expressed with fall in reproductive organ weights and gonadosomatic index (GSI). Lead acetate disrupted spermatogenesis as indicated by sperm cell count reduction and increased sperm malformation percentage. Lead acetate-deteriorated steroidogenesis is evoked by minimized serum testosterone along with maximized follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels. Testicular oxidative, inflammatory, and apoptotic cascades are revealed by elevated acid phosphatase (ACP) and sorbitol dehydrogenase (SDH) serum leakage, declined testicular total antioxidative capacity (TAC) with elevated total oxidative capacity (TOC), tumor necrosis factor alpha (TNF-α), caspase-3 levels, lessened androgen receptor (AR) expression, and histopathological lesions against control. Our research highlights that C. vulgaris or S. platensis therapy can modulate lead acetate-promoted testicular dysfunction via their antioxidant activity as expressed by elevated TAC and reduced TOC, immunomodulatory effect as indicated by lessened TNF-α level, and anti-apoptotic potential that was revealed by minimized caspase-3 levels. As well as restoration of testicular histoarchitecture, androgen receptor, steroidogenesis, and spermatogenesis were detected with better impacts to S. platensis comparing with C. vulgaris. Therefore, further clinical trials are needed to test S. platensis and C. vulgaris as a promising candidate in treating male infertility.

Emerging Technologies for Degradation of Dichlorvos: A Review

Dichlorvos (O,O-dimethyl O-(2,2-dichlorovinyl)phosphate, DDVP) is a widely acknowledged broad-spectrum organophosphorus insecticide and acaracide. This pesticide has been used for more than four decades and is still in strong demand in many developing countries. Extensive application of DDVP in agriculture has caused severe hazardous impacts on living systems. The International Agency for Research on Cancer of the World Health Organization considered DDVP among the list of 2B carcinogens, which means a certain extent of cancer risk. Hence, removing DDVP from the environment has attracted worldwide attention. Many studies have tested the removal of DDVP using different kinds of physicochemical methods including gas phase surface discharge plasma, physical adsorption, hydrodynamic cavitation, and nanoparticles. Compared to physicochemical methods, microbial degradation is regarded as an environmentally friendly approach to solve several environmental issues caused by pesticides. Till now, several DDVP-degrading microbes have been isolated and reported, including but not limited to Cunninghamella, Fusarium, Talaromyces, Aspergillus, Penicillium, Ochrobium, Pseudomonas, Bacillus, and Trichoderma. Moreover, the possible degradation pathways of DDVP and the transformation of several metabolites have been fully explored. In addition, there are a few studies on DDVP-degrading enzymes and the corresponding genes in microorganisms. However, further research relevant to molecular biology and genetics are still needed to explore the bioremediation of DDVP. This review summarizes the latest development in DDVP degradation and provides reasonable and scientific advice for pesticide removal in contaminated environments.

Zingiber officinale ethanolic extract attenuates oxidative stress, steroidogenic gene expression alterations, and testicular histopathology induced by sodium arsenite in male rats

Arsenic (As) indelibly exists in the environment and may reach to a food chain. Flavors and herbs are recognized sources of natural antioxidants that play imperative against harmful chemical pollutants. Ginger is utilized around the world as a zesty condiment. This study assessed the ability of ginger extract (GE) as a protector to improve regenerative disabilities initiated by sodium arsenate in reproductive functions in male rats. Thirty-two Sprague-Dawley male rats weighted 240 ± 10 g were arbitrarily relegated into four experimental groups (n = 8): the control group; the GE-treated group received at 100 mg/kg BW; the As-treated group received sodium arsenite at 10 mg/kg BW; the fourth group received sodium arsenite additionally GE at mentioned doses for 4 weeks. Phytochemical results of GE revealed that GE had good antioxidative characteristics and high content of total flavonoid, tannins, alkaloids, and total phenolic components. Simultaneously, treatment of GE showed protection against oxidative stress induced by As and restoration of the serum cholesterol, testosterone, LH, and sperm parameter to normal levels. GE significantly improved the antioxidant activities (GSH, SOD, and CAT) as well as H2O2 and MDA in rats received concurrently the GE and As compared with control group. Moreover, the expression of genes controlling the cholesterol transportation and testosterone synthesis (SR-B1, StAR, CYP11A1, 3b-HSD, 17b-HSD, and CYP17a) as well as LHR showed a meaningful improvement in rats treated by GE plus As compared with their expression in the As-treated group. Besides, GE treatment exhibited significant recovered testis histopathological alterations, reduced the arsenic content in testes, and improved the sperm parameters.

Non-linear model analysis of the relationship between cholinesterase activity in rats exposed to 2, 2-dichlorovinyl dimethylphosphate (dichlorvos) and its metabolite concentrations in urine

Urinary dialkylphosphates (DAPs) are measured to assess exposure to organophosphorus pesticides (OPs), but they are common metabolites of OPs and not specific indices for individual agents. Biomonitoring (BM) of urinary DAPs has been widely adopted as an assessment of individual exposure in general environments, however, guidance values for DAPs based on health effects have yet to be established. The present study aimed to clarify the relationship between the amount of urinary dimethylphosphate (DMP), a metabolite of dichlorvos (DDVP), and the inhibition of cholinesterase (ChE) activity in rats exposed to DDVP. The relationship was analyzed using a nonlinear model analysis, and the excretion level of urinary DMP equivalent to ChE 20 % inhibition (EL20) and the lower limit of the 95 % confidence interval of EL20 (ELL20) were estimated. EL20 and ELL20 (mg/24 h urine) of brain, erythrocyte, and plasma ChE activities after 10-day administration of DDVP were 0.21 and 0.15, 0.11 and 0.06, and 0.23 and 0.09, respectively. Extrapolating ELL20 of the brain ChE to humans, the range of 24 h urinary DMP concentration according to the 20 % inhibition of cholinesterase activity was estimated to be 20.5-30.8 mg/l. In conclusion, the amount of urinary DMP as ELL20 for DDVP exposure was identified and could probably be used as a novel index for the assessment of risk from OP exposure. Further studies are needed to clarify the ELL20 s derived from OPs other than DDVP, for informing efforts to establish guidance values of urinary OP metabolites that should prevent neurotoxicity.

Moringa oleifera seed oil partially abrogates 2,3-dichlorovinyl dimethyl phosphate (Dichlorvos)-induced cardiac injury in rats: evidence for the role of oxidative stress

OBJECTIVES

Cardiovascular diseases are major causes of non-infectious diseases globally. The use of pesticides has been linked with the high global burden of non-communicable diseases. Despite the indiscriminate exposure to dichlorvos (DDVP) by inhalation, no report exists on its possible cardiotoxic effect. This study investigated the cardiotoxicity of DDVP exposure by inhalation and the possible role of Moringa oleifera seed oil.

METHODS

Twenty-one male rats were randomly assigned into 3 groups. Group A (control) received only standard rat diet and water ad' libitum, group B (DDVP) was exposed to DDVP via inhalation for 15 min daily in addition to rat diet and water, and group C (DDVP + M. oleifera seed oil) received treatment as group B as well as 300 mg/kg of M. oleifera seed oil p.o for 28 days.

RESULTS

Significant reductions in body weight gain and cardiac weight were observed in DDVP-exposed animals (p<0.05). Similarly, 28 days of exposure to DDVP led to a significant increase in lactate dehydrogenase, creatinine kinase and troponin (p<0.05). DDVP-exposed rats also showed a significant increase in malondialdehyde, and a significant decline in superoxide dismutase and glutathione peroxidase (p<0.05). However, catalase was comparable in DDVP-exposed and control rats. Histopathological observations of the cardiac tissue revealed that DDVP caused marked fat degeneration and necrosis of the myocardial layer. The changes in DDVP-exposed rats were significantly, though not completely, restored by M. oleifera seed oil administration.

CONCLUSIONS

This study provides novel mechanistic information on the cardiotoxicity of DDVP inhalation, and the antioxidant potential of M. oleifera seed oil.

Effects of phosalone plant pesticide on sperm parameters and sexual hormone levels in Wistar rats: An experimental study

Background

Phosalone is an organophosphate insecticide, applied to control of plant pests. This compound has various side effects because it acts as an acetyl cholinesterase enzyme inhibitor.

Objective

To investigate the effects of phosalone on the sperm parameters of and levels of sex hormones in adult male rats.

Materials and Methods

In this experimental study, 16 adult (8-12 wk) male Wister rates (weighing 220-280 gr) were randomly assigned into 4 groups (n = 4/each). Group 1 (control) received only routine adequate water and food; Group 2, 3, and 4 received different low doses of phosalone (60, 90, and 120 mg/kg respectively). The rats were weighed and anesthetized after 48 days. Sperm parameters including number, motility, and viability as well as sex hormones (such as Luteinizing Hormone, Follicle Stimulating Hormone, and testosterone) were evaluated and compared after removing the epididymis tail.

Results

Our results showed that phosalone decreased sperm motility, viability, and number in a dose-dependent manner. The level of FSH and LH was increased, and testosterone was decreased. Also, depending on the dose, phosalone decrease sperm motility and viability (p ≤ 0.001), while the level of FSH and LH was increased and testosterone was decreased (p = 0.861).

Conclusion

Phosalone has negative effects on reproductive indices in male rats and can cause serious damage and decrease the number and sperms motility. It can also cause infertility due to changing the concentration of hormones.

Targeting gap junctional intercellular communication by hepatocarcinogenic compounds

Gap junctions in liver, as in other organs, play a critical role in tissue homeostasis. Inherently, these cellular constituents are major targets for systemic toxicity and diseases, including cancer. This review provides an overview of chemicals that compromise liver gap junctions, in particular biological toxins, organic solvents, pesticides, pharmaceuticals, peroxides, metals and phthalates. The focus in this review is placed upon the mechanistic scenarios that underlie these adverse effects. Further, the potential use of gap junctional activity as an in vitro biomarker to identify non-genotoxic hepatocarcinogenic chemicals is discussed.

Biochemical and histopathological effects of sub-acute exposure of albino rats to fumigants - dichlorvos and cypermethrin

Cypermethrin (CYP) is one of the most common active ingredients in most insecticides, mosquito coils and powder used in Nigeria. dichlorvos (DDVP) is the most indiscriminately used fumigant in most rural and sub-urban areas in Nigeria. These fumigants can easily be accessed without proper method of usage thus exposing the population to their toxic effects. As a result, this study was initiated to determine the effects of sub-acute exposure of CYP and DDVP on some biochemical and histopathological parameters of albino rats. In this study, forty (40) albino rats of 10 groups of 4 rats per group, with one group serving as control, were exposed to these fumigants in a poorly ventilated area for 4hours per day over 2, 4 and 6 weeks. The results showed observable changes in liver enzyme activities (p<0.05) in groups exposed to DDVP for 2, 4 and 6 weeks. The groups exposed to CYP showed mild changes in liver enzyme activities when compared with the DDVP groups. Increase in activity of the liver enzymes was also observed in the groups exposed to a mixture of DDVP+CYP for 2, 4 and 6 weeks. The urea, creatinine and electrolytes levels in all the groups exposed to DDVP, CYP and DDVP+CYP for 2, 4 and 6weeks were significantly (p<0.05) increased. Also WBC and platelets in all the groups exposed to DDVP and CYP recorded significant changes. The histology report of the lungs and liver showed moderate lymphocytic infiltration and hepatocytic steatosis which progressed with duration of exposure to the fumigants, while the kidneys showed no remarkable changes. The results of this study suggest that DDVP and CYP have relative toxic effects in the exposed animals and should be used with caution to avoid human exposure to their visible toxicities.

Thymoquinone attenuates testicular and spermotoxicity following subchronic lead exposure in male rats: Possible mechanisms are involved

AIMS

The testis is one of the main target organs for lead (Pb) toxicity. The current study was investigated the mechanism (s) of the therapeutic potential of thymoquinone (TQ), the active principle of Nigella sativa seed, against testicular toxicity following subchronic Pb exposure in the light of cytopathic effects, apoptotic signaling pathways, oxidative stress, serum sex hormones levels and testicular aromatase gene expression.

MATERIALS AND METHODS

Thirty-two male albino rats were randomly allocated into control, PbAc (20 mg PbAc/kg bwt, orally), TQ (5 mg TQ/kg bwt dissolved in corn oil, orally), and PbAc + TQ groups for 56 successive days.

KEY FINDINGS

PbAc-treated rats showed significant decrease of testes and epididymes weights, sperm count, motility and viability, spermatogenesis score and serum FSH, LH, testosterone and estradiol levels, as well as a significant decreased testicular antioxidant molecules (Superoxide dismutase enzyme and reduced glutathione), and a significant elevation of sperm abnormalities, oxidative biomarkers (Malondialdehyde and Nitric oxide) compared to a control group. In addition, Pb induced significant downregulation of aromatase gene expression, activation of Bax and Caspase-3 apoptotic pathways. Moreover, Pb caused complete seminiferous tubules hyalinization (38%), germinal epithelium sloughing (15%) and hypocellularity (8%). However, administration of TQ with PbAc improved sperm quality, testicular histology and oxidative/antioxidative status, and serum levels of LH, testosterone and E2 with respect to PbAc group. Additionally, TQ with PbAc significantly lessen the staining intensity and the area of Bax and Caspase-3 immunoexpression.

SIGNIFICANCE

TQ might exert its acceptable therapeutic potential against Pb-induced testicular and spermotoxicity via anti-oxidative, endocrine and anti-apoptotic pathways.

[Reproductive Toxicological Research as Countermeasures to Declining Birth Rate]

Research into reproductive toxicology may lead to one of the countermeasures to the declining birth rate observed in industrialized countries. Some chemicals can pose risks to human reproduction that is a multistage process starting from the development of male and female germ cells to childbirth and the subsequent growth and development of the child. In Japan, the government has amended law enforcement, i.e., the Regulations on Labor Standards for Women, recently to improve protection for pregnant women against reproductive chemical hazards in workplaces. Male workers may also be protected against such hazards if appropriate risk assessment and the following management are performed as required by the Industrial Safety and Health Law. However, it remains a concern that an unexpected adverse outcome due to an unknown reproduction hazard may occur owing to the use of chemicals not listed in the regulations. This is because the toxicity of a large number of chemicals has not been entirely revealed. Moreover, it is often difficult to determine from a Safety Data Sheet for a product of interest whether the chemicals contained in the product do not have reproductive toxicity or the toxicity data are just not available because of lack of pertinent studies. Thus, researchers in the field of occupational and environmental health need to make effort to fill in such data gaps and to raise the awareness among the public the importance of experimental and epidemiological studies. Study designs for investigating subclinical effects, mechanisms of reproductive toxicity, exposure levels, and dose-response relationships to determine environmental standards are also required.

Curcumin and Quercetin Ameliorated Cypermethrin and Deltamethrin-Induced Reproductive System Impairment in Male Wistar Rats by Upregulating The Activity of Pituitary-Gonadal Hormones and Steroidogenic Enzymes

Background

Dietary antioxidants protect tissues and organs against insecticides/xenobiotic-induced damage. In the present study, we evaluated the results of exposure to synthetic pyrethroid insecticides, cypermethrin (Cyp) and deltamethrin (Del) and possible protective effects of curcumin and quercetin on reproductive system in male Wistar rats.

Materials and Methods

In this controlled experimental study, 42 male Wistar rats were randomly divided into 7 groups of 6 animals. Group A served as control, group B was exposed to Cyp (2 mg/kg.bw), group C was exposed to Del (2 mg/kg.bw), group D was exposed to Cyp+Del (2 mg/kg.bw each), group E was exposed to Cyp+Del and treated with curcumin (100 mg/kg.bw), group F was exposed to Cyp+Del and treated with quercetin (100 mg/kg.bw) and group G was exposed to Cyp+Del and treated with quercetin+curcumin for 45 days.

Results

Exposure to Cyp and Del caused decreases in reproductive organs weight, sperm count, sperm motility, level of sex hormones viz. testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH), steroidogenic enzymes viz. 3β-hydroxyl steroid dehydrogenase (3β-HSD) and 17β-HSD, non-enzymatic antioxi- dant glutathione (GSH) and enzymatic antioxidants viz. superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) activity and increases in sperm abnormalities and lipid peroxidation (LPO). The exposure also adversely affected the histo-achitecture of testes. Single and combined treatment with curcumin and quercetin significantly ameliorated Cyp and Del-induced damage in reproductive system.

Conclusion

Curcumin and quercetin protected against Cyp and Del-induced reproductive system toxicity and oxidative damage in rats. The increases in activities of 3β-HSD and 17β-HSD with concomitant increases in testosterone were mainly responsible for ameliorating effects of curcumin and quercetin. Curcumin showed slightly better activity as compared to quercetin. The combination of both antioxidants offered more protection compared to each one alone.

Betanin reduces organophosphate induced cytotoxicity in primary hepatocyte via an anti-oxidative and mitochondrial dependent pathway

Organophosphates (OP) are potent pesticide commonly utilized in agricultural and domestic use. However, plentitude of data represent their side effects in different body tissues. We attempted to study whether betanin (a natural pigment) is able to mitigate some OPs-induced hepatotoxicity in primary rat hepatocytes. Cell viability, lactate dehydrogenase (LDH) leakage, reactive oxygen species (ROS) formation, lipid peroxidation (LPO), glutathione (GSH) depletion and mitochondrial depolarization were tested as toxicity markers. The outcomes revealed that betanin (25μM) significantly increased cell viability, plummeted ROS formation and LPO, restored cellular GSH reservoirs and protected mitochondria after chlorpyrifos (CPF) (300μM), diazinon (DZN) (600μM) and dichlrovos (DDVP) (400μM) treatment. Taken together, all data suggests the potential protective role of betanin in OPs-induced hepatotoxicity in which the mechanism appears to be inhibition of ROS formation and mitochondrial protection.

Fluoride Exposure Aggravates the Testicular Damage and Sperm Quality in Diabetic Mice: Protective Role of Ginseng and Banaba

Fluoride toxicity is known to pose infertility in fluoride-intoxicated animals as well as in people residing in fluoride endemic zones. The present study addresses the degree of impairments caused due to co-exposure of high fluoride toxicity in diabetic mice. Swiss mice, Mus musculus, were subjected to fluoride toxicity by providing fluoride-supplemented drinking water (600 ppm NaF) for a period of 30 days after the confirmation of streptozotocin-induced diabetes(STZ, 50 mg/kgbw). Consequently, aggravated hyperglycemia and tissue fluoride accumulation were witnessed in fluoride-intoxicated diabetic mice; later, these toxicated mice were treated with ginseng extract (GE) and banaba leaf extract, (BLE) at dose of 150 mg/kgbw/day alone and in combination for 15 and 30-day duration to check the efficacy of phytoextracts in reversing the toxicity. The spermatological indices studied, such as sperm density, motility, viability and morphology as well as the testicular biochemical parameters showed enhanced impairment in reproductive status of fluoride-intoxicated diabetic mice. Further, 15-days administration of GE and BLE in combination at a dose of 150 mg/kgbw/day was found to be beneficial in normalizing the alterations observed upon fluoride intoxication to diabetic mice. However, the correlates showed moderate association between blood glucose levels and the spermatological as well as biochemical indices wherein the tissue fluoride levels correlate least.

Quercetin protects HCT116 cells from Dichlorvos-induced oxidative stress and apoptosis

The present study was designed to assess the possible protective effects of Quercetin (QUER), a flavonoid with well-known pharmacological effects, against Dichlorvos (DDVP)-induced toxicity in vitro using HCT116 cells. The cytotoxicity was monitored by cell viability, reactive oxygen species (ROS) generation, anti-oxidant enzyme activities, malondialdehyde (MDA) production, and DNA fragmentation. The apoptosis was assessed through the measurement of the mitochondrial transmembrane potential (ΔΨm) and caspase activation. The results indicated that pretreatment of HCT116 cells with QUER, 2 h prior to DDVP exposure, significantly decreased the DDVP-induced cell death, inhibited the ROS generation, modulated the activities of catalase (CAT) and superoxide dismutase (SOD), and reduced the MDA level. The reductions in mitochondrial membrane potential, DNA fragmentation, and caspase activation were also attenuated by QUER. These findings suggest that dietary QUER can protect HCT116 cells against DDVP-induced oxidative stress and apoptosis.

Quercetin mitigates fenitrothion-induced testicular toxicity in rats

Fenitrothion (FNT) is a widely used organophosphorus pesticide in agriculture. Quercetin (QR), a plant-derived flavonoid, has a free radical scavenging property. This study investigated the protective effect of QR on FNT-induced testicular toxicity in rats. Twenty-four male rats were divided into four groups. Group I (control) received normal saline. Group II was administered QR at the dose of 50 mg kg(-1) b.wt. Group III was orally administered FNT (20 mg kg(-1) b.wt). Group IV was gavaged FNT and QR together at the same doses. All administrations were performed daily by gavage and maintained for 70 days. Sperm parameters and histopathological changes in testes were investigated. Serum testosterone and luteinising hormone were estimated using radioimmunoassay kits. In testes, expressions of steroidogenic genes (3β-hydroxysteroid dehydrogenase type 6, 17 β-hydroxysteroid dehydrogenase type 3 and steroidogenic factor-1) and oxidative stress genes (catalase and superoxide dismutase) were determined using real-time PCR. FNT administration caused significant decreases in sperm count, motility and hormonal levels, a significant increase in abnormal sperm morphology and a significant down-regulation of steroidogenic and antioxidant genes in the testis. However, QR administration ameliorated FNT-induced toxic effects. Our results concluded that QR effectively mitigated testicular damage induced by FNT in rats.

Lycopene attenuates dichlorvos-induced oxidative damage and hepatotoxicity in rats

Because of the widespread use of dichlorvos (DDVP) for domestic applications, evaluation of their toxic effects is of major concern to public health. Lycopene may lower oxidative stress by a mechanism that is not fully elucidated. The present study was undertaken to evaluate the protective efficacy of lycopene in terms of normalization of altered biochemical parameters following DDVP treatment in rats. Animals were divided into four groups. The first group was used as control, while groups 2, 3, and 4 were orally treated with lycopene (10 mg kg−1 body weight (b.w.)), DDVP (1.6 mg kg−1 b.w.), and DDVP plus lycopene, respectively. Results showed that oral administration of DDVP for 30 days increased the levels of lipid peroxidation markers such as malondialdehyde, 4-hydroxynonanal, and protein carbonyl content in liver. Also, a decrease in levels of vitamin C, vitamin E, and reduced glutathione was detected due to DDVP administration. These were accompanied by a decrease in the activities of antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and glutathione- S-transferase in the liver tissue. Moreover, DDVP increased the activities of serum transaminases, alkaline phosphatase, lactate dehydrogenase, and lipoxygenase, and the levels of bilirubin, total cholesterol, low-density lipoprotein cholesterol, triglyceride and DNA–protein crosslinks, and 8-hydroxy-2-deoxyguanosine, while decreased the level of high-density lipoprotein cholesterol. Our results provide new insights into the biochemical studies of relation between DDVP hepatotoxicity and lycopene treatment. Administration of lycopene to DDVP-treated rats reverted the status of hepatic markers to near-normal levels. These data suggest that lycopene can protect against the liver damage induced by DDVP.

Surfactant-modified montmorillonite as a nanosized adsorbent for removal of an insecticide: kinetic and isotherm studies

Surfactant-modified montmorillonites (MMT) were prepared using trimethyloctylammonium bromide (TMOAB) and employed as a nanosized adsorbent to remove diazinon from aqueous solutions. The prepared adsorbent was characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). The dependence of removal efficiency on initial diazinon concentration, amount of adsorbent, pH of the solution and ionic strength was investigated. The affinity sequence for ion adsorption on TMOAB/MMT was in the order: without anion> sodium carbonate> sodium bicarbonate> sodium sulphate> sodium chloride. The adsorption kinetic and isotherm were best fit by a pseudo-second-order kinetic and Langmuir isotherm models, respectively.

Lutein alleviates arsenic-induced reproductive toxicity in male mice via Nrf2 signaling

This study aims to investigate the mechanisms involved in the action of lutein (LU) alleviating arsenic-induced reproductive toxicity using mice model. Forty male Kunming mice were received following treatments by gavage: normal saline solution (control), arsenic trioxide (ATO; 5 mg/kg/day), LU (40 mg/kg/day), and ATO + LU (5 mg/kg/day + 40 mg/kg/day). At the end, the mice were killed by cervical dislocation and weighed. Pathological examination was done on the testis. The biomedical parameters including superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed. The messenger RNA (mRNA) and protein expression of Nrf2, heme oxygenase 1 (HO-1), glutathione S-transferase (GST), nicotinamide adenine dinucleotide phosphate dehydrogenase, quinone 1 (NQO1) in testis were detected by real-time polymerase chain reaction and Western blot. We found that there was a decrease in sperm count; testis somatic index; the activities of SOD, GSH, total antioxidative capacity ( p < 0.01, respectively) in ATO-treated mice, while there was an increase in the levels of sperm abnormalities, MDA, and 8-OHdG than control ( p < 0.01, respectively). The groups treated with ATO + LU showed recovery of the measured parameters between those of ATO or saline-treated group. The antagonized interaction between ATO and LU was statistically significant ( p < 0.01). Mice treated with ATO + LU also showed greater mRNA expression of Nrf2, HO-1, NQO1, and GST than ATO or saline-treated groups. These findings suggest that LU alleviates reproductive toxicity induced by arsenic in male mice via Nrf2 signaling, which implicates a possible mechanism of LU in preventing the reproductive injury, and elucidates that consuming the rich plant sources of LU will alleviate the reproductive toxicity induced by chemicals.

Changes in glucose metabolism and reversion of genes expression in the liver of insulin-resistant rats exposed to malathion. The protective effects of N-acetylcysteine

Organophosphorus pesticides are known to disturb glucose homeostasis and increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on insulin signaling pathways and the protective effects of N-acetylcysteine (NAC). Malathion (200 mg/kg) and NAC (2 g/l) were administered orally to rats, during 28 consecutive days. Malathion increases plasma glucose, plasma insulin and glycated hemoglobin levels. Further, we observed an increase of insulin resistance biomarkers and a decrease of insulin sensitivity indices. The GP, GSK3β and PEPCK mRNA expressions were amplified by malathion while, the expression of glucokinase gene is down-regulated. On the basis of biochemical and molecular findings, it is concluded that malathion impairs glucose homeostasis through insulin resistance and insulin signaling pathways disruptions in a way to result in a reduced function of insulin into hepatocytes. Otherwise, when malathion-treated rats were compared to NAC supplemented rats, fasting glucose and insulin levels, as well as insulin resistance indices were reduced. Furthermore, NAC restored liver GP and PEPCK expression. N-acetylcysteine showed therapeutic effects against malathion-induced insulin signaling pathways disruption in liver. These data support the concept that antioxidant therapies attenuate insulin resistance and ameliorate insulin sensitivity.

Protective Effects of Intralipid and Caffeic Acid Phenethyl Ester on Nephrotoxicity Caused by Dichlorvos in Rats

The protective effects of Caffeic Acid Phenethyl Ester (CAPE) and intralipid (IL) on nephrotoxicity caused by acute Dichlorvos (D) toxicity were investigated in this study. Forty-eight Wistar Albino rats were divided into 7 groups as follows: Control, D, CAPE, intralipid, D + CAPE, D + IL, and D + CAPE + IL. When compared to D group, the oxidative stress index (OSI) values were significantly lower in Control, CAPE, and D + IL + CAPE groups. When compared to D + IL + CAPE group, the TOS and OSI values were significantly higher in D group (P < 0.05). When mitotic cell counts were assessed in the renal tissues, it was found that mitotic cell count was significantly higher in the D group while it was lower in the D + CAPE, D + IL, and D + IL + CAPE groups when compared to the control group (P < 0.05). Also, immune reactivity showed increased apoptosis in D group and low profile of apoptosis in the D + CAPE group when compared to the Control group. The apoptosis level was significantly lower in D + IL + CAPE compared to D group (P < 0.05) in the kidneys. As a result, we concluded that Dichlorvos can be used either alone or in combination with CAPE and IL as supportive therapy or as facilitator for the therapeutic effect of the routine treatment in the patients presenting with pesticide poisoning.

Nanoparticle Delivery Systems Reduce the Reproductive Toxicity of Docetaxel in Rodents

Various docetaxel (DTX)-loaded nanoparticle delivery systems have been designed to enhance the solubility and pharmacological effects of DTX. However, the toxicity changes of these nano-modified DTX (nano-DTX) are not yet clear enough. Herein, to compare the reproductive toxicity between conventional DTX and nano-DTX, we performed sperm toxicity test in mice, and fertility and early embryo-fetal developmental toxicity test in rats. It was found that DTX severely repressed spermatogenesis and sperm motility, and dramatically increased sperm abnormality in mice and rats. Moreover, DTX significantly decreased copulation, conception and fertility indexes in rats, and no positive pregnant female rat was obtained after treatment with DTX. However, nano-DTX significantly reduced DTX-induced toxicity to sperm. Most importantly, nano-DTX obviously converted DTX-induced fertility and early embryo-fetal developmental toxicity. Furthermore, organ weights and histopathology examination revealed DTX, but not nano-DTX, significantly decreased testis and epididymis weights, and induced obvious histopathological atrophy of testes and epididymides in rats. Further studies indicated that changed activity of lactate dehydrogenase C4 (LDH-C4) in rodents testes was mainly responsible for the above observations. These results strongly support the idea that DTX-loaded nanoformulations have the potential to overcome the reproductive toxicity of DTX.

Effects of lead acetate on testicular function and caspase-3 expression with respect to the protective effect of cinnamon in albino rats

The aim of this study was to investigate the protective effects of cinnamon on lead acetate induced reproductive toxicities in rats. Thirty-two male rats were randomly divided into 4 groups, 8 rats in each. Control rats received distilled water, while treated rats received lead acetate (30 mg/kg), cinnamon (250 mg/kg) and lead acetate and cinnamon (30 mg/kg and 250 mg/kg) for 60 days by gavage tube. In cinnamon treated rats, the relative weights of testes, epididymis, seminal and prostate glands were significantly (P < 0.05) increased compared with that in lead acetate treated rats. Sperm cell concentration and viability were significantly (P < 0.05) reduced, while sperm abnormalities were significantly (P < 0.05) increased in lead treated rats. The superoxide dismutase (SOD) and catalase activities were significantly reduced (P < 0.001) in lead acetate treated rats compared to the other groups, while the addition of cinnamon to lead acetate improved the level of SOD compared to the lead treated group. There was a marked reduction (P < 0.001) in the expression of androgen receptor and significant (P < 0.001) increase in the level of caspase-3 protein expression in the testis of lead treated rats. In conclusion, cinnamon exhibited protective effect on reproductive system by inhibiting lead acetate induced oxidative stress and excessive cell apoptosis.

Fenitrothion alters sperm characteristics in rats: ameliorating effects of palm oil tocotrienol-rich fraction

Exposure to organophosphate insecticides such as fenitrothion (FNT) in agriculture and public health has been reported to affect sperm quality. Antioxidants may have a potential to reduce spermatotoxic effects induced by organophosphate. The present study was carried out to evaluate the effects of palm oil tocotrienol-rich fraction (TRF) in reducing the detrimental effects occurring in spermatozoa of FNT-treated rats. Adult male Sprague-Dawley rats were divided into four equal groups: a control group and groups of rats treated orally with palm oil TRF (200 mg/kg), FNT (20 mg/kg) and palm oil TRF (200 mg/kg) combined with FNT (20 mg/kg). The sperm characteristics, DNA damage, superoxide dismutase (SOD) activity, and levels of reduced glutathione (GSH), malondialdehyde (MDA), and protein carbonyl (PC) were evaluated. Supplementation with TRF attenuated the detrimental effects of FNT by significantly increasing the sperm counts, motility, and viability and decreased the abnormal sperm morphology. The SOD activity and GSH level were significantly increased, whereas the MDA and PC levels were significantly decreased in the TRF+FNT group compared with the rats receiving FNT alone. TRF significantly decreased the DNA damage in the sperm of FNT-treated rats. A significant correlation between abnormal sperm morphology and DNA damage was found in all groups. TRF showed the potential to reduce the detrimental effects occurring in spermatozoa of FNT-treated rats.

Fenitrothion action at the endocannabinoid system leading to spermatotoxicity in Wistar rats

Organophosphate (OP) compounds as anticholinesterase agents may secondarily act on diverse serine hydrolase targets, revealing unfavorable physiological effects including male reproductive toxicity. The present investigation proposes that fenitrothion (FNT, a major OP compound) acts on the endocannabinoid signaling system in male reproductive organs, thereby leading to spermatotoxicity (sperm deformity, underdevelopment, and reduced motility) in rats. FNT oxon (bioactive metabolite of FNT) preferentially inhibited the fatty acid amide hydrolase (FAAH), an endocannabinoid anandamide (AEA) hydrolase, in the rat cellular membrane preparation from the testis in vitro. Subsequently, male Wistar rats were treated orally with 5 or 10mg/kg FNT for 9 weeks and the subchronic exposure unambiguously deteriorated sperm motility and morphology. The activity-based protein profiling analysis with a phosphonofluoridate fluorescent probe revealed that FAAH was selectively inhibited among the FNT-treated cellular membrane proteome in testis. Intriguingly, testicular AEA (endogenous substrate of FAAH) levels were elevated along with the FAAH inhibition caused by the subchronic exposure. More importantly, linear regression analyses for the FNT-elicited spermatotoxicity reveal a good correlation between the testicular FAAH activity and morphological indices or sperm motility. Accordingly, the present study proposes that the FNT-elicited spermatotoxicity appears to be related to inhibition of FAAH leading to overstimulation of the endocannabinoid signaling system, which plays crucial roles in spermatogenesis and sperm motility acquirement.

A potential target for organophosphate insecticides leading to spermatotoxicity

Organophosphate (OP) insecticides as an anticholinesterase also act on the diverse serine hydrolase targets, thereby revealing secondary or unexpected toxic effects including male reproductive toxicity. The present investigation detects a possible target molecule(s) for OP-induced spermatotoxicity (sperm deformity, underdevelopment, and reduced motility) from a chemical standpoint. The activity-based protein profiling (ABPP) approach with a phosphonofluoridate fluorescent probe pinpointed the molecular target for fenitrothion (FNT, a major OP insecticide) oxon (bioactive metabolite of FNT) in the mouse testicular membrane proteome, i.e., FNT oxon phosphorylates the fatty acid amide hydrolase (FAAH), which plays pivotal roles in spermatogenesis and sperm motility acquirement. Subsequently, mice were treated orally with vehicle or FNT for 10 days, and FAAH activity in testis or epididymis cauda was markedly reduced by the subacute exposure. ABPP analysis revealed that FAAH was selectively inhibited among the FNT-treated testicular membrane proteome. Accordingly, FAAH is a potential target for OP-elicited spermatotoxicity.