Neurochemical alterations following the exposure to di-n-butyl phthalate in rats

Neuroprotective role of chlorogenic acid against hippocampal neuroinflammation, oxidative stress, and apoptosis following acute seizures induced by pentylenetetrazole

This study investigated the neuroprotective effect of chlorogenic acid (CGA) on pentylenetetrazole (PTZ)-induced acute epileptic seizures in mice. Epileptic animals received CGA (200 mg/kg) or sodium valproate (standard antiepileptic agent, 200 mg/kg) for four weeks. Results revealed that pre-administration of CGA significantly reversed the behavioral changes following pentylenetetrazole (PTZ) injection. Further, CGA pre-treatment caused significant increases in acetylcholinesterase (AChE) activity and brain-derived neurotrophic factor (BDNF) levels, along with marked increases in dopamine, norepinephrine, and serotonin levels. Additionally, the increased antioxidant enzymes activities, along with higher glutathione (GSH) contents and upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) gene expression, were indicative of a notable improvement in the cellular antioxidant defense in mice treated with CGA. These results were associated with lowered malondialdehyde (MDA) and nitric oxide (NO) levels. Moreover, epileptic mice that received CGA showed significant declines in the content of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and nuclear factor kappa-B (NF-κB), besides downregulating inducible nitric oxide synthase (iNOS) expression. Remarkably, CGA counteracted hippocampal apoptosis by lessening the levels of pro-apoptotic biomarkers [Bcl-2-associated X protein (Bax) and caspase-3] and increasing the anti-apoptogenic marker level of B-cell lymphoma 2 (Bcl-2). The hippocampal histopathological findings corroborated the abovementioned changes. In sum, these findings suggest that CGA could mediate the neuroprotective effect against PTZ-induced epilepsy via modulation of neurotransmitters, oxidative damage, neuroinflammation, and apoptosis. CGA, therefore, could be considered a valuable antiepileptic therapeutic supplement.

Thyroid and neurobehavioral effects of DiNP on GH3 cells and larval zebrafish (Danio rerio)

Diisononyl phthalate (DiNP) has been used to replace bis(2-ethylhexyl) phthalate (DEHP) and is frequently found in the environment and humans. DiNP is reported for its anti-androgenic activity; however, little is known about its effects on thyroid function and neurodevelopment. In the present study, the thyroid disruption and neurobehavioral alteration potential of DiNP and its major metabolites were assessed in a rat pituitary carcinoma cell line (GH3) and embryo-larval zebrafish (Danio rerio). In GH3 cells, exposure to DiNP and its metabolites not only increased proliferation but also induced transcriptional changes in several target genes, which were different from those observed with DEHP exposure. In larval fish, a 5-day exposure to DiNP caused significant increases in thyroid hormone levels, following a similar pattern to that reported for DEHP exposure. Following exposure to DiNP, the activity of the larval fish decreased, and neurodevelopment-related genes, such as c-fos, elavl3, and mbp, were down-regulated. These changes are generally similar to those observed for DEHP. Up-regulation of gap43 and down-regulation of elavl3 gene, which are important for both thyroid hormone production and neurodevelopment, respectively, support the potential for both thyroid and behavioral disruption of DiNP. Overall, these results emphasize the need to consider the adverse thyroid and neurodevelopmental effects in developing regulations for DEHP-replacing phthalates.

Innovative Microbial Immobilization Strategy for Di-n-Butyl Phthalate Biodegradation Using Biochar-Calcium Alginate-Waterborne Polyurethane Composites

Di-n-butyl phthalate (DBP) is a prevalent phthalate ester widely used as a plasticizer, leading to its widespread presence in various environmental matrices. This study presents an innovative microbial immobilization strategy utilizing biochar, calcium alginate (alginate-Ca, (C12H14CaO12)n), and waterborne polyurethane (WPU) composites to enhance the biodegradation efficiency of DBP. The results revealed that rice husk biochar, pyrolyzed at 300 °C, exhibits relatively safer and more stable physical and chemical properties, making it an effective immobilization matrix. Additionally, the optimal cultural conditions for Bacillus aquimaris in DBP biodegradation were identified as incubation at 30 °C and pH 7, with the supplementation of 0.15 g of yeast extract, 0.0625 g of glucose, and 1 CMC of Triton X-100. Algal biotoxicity results indicated a significant decrease in biotoxicity, as evidenced by an increase in chlorophyll a content in Chlorella vulgaris following DBP removal from the culture medium. Finally, microbial community analysis demonstrated that encapsulating B. aquimaris within alginate-Ca and WPU layers not only enhanced DBP degradation, but also prevented ecological competition from indigenous microorganisms. This novel approach showcases the potential of agricultural waste utilization and microbial immobilization techniques for the remediation of DBP-contaminated environments.

Neurotoxicity of dibutyl phthalate in zebrafish larvae: Decreased energy acquisition by neurons

This work was designed to investigate the neurotoxic effects of the typical plasticizer dibutyl phthalate (DBP) using zebrafish larvae as a model. The results of exhibited that zebrafish larvae exposed to DBP at concentrations of 5 μg/L and 10 μg/L exhibited brain malformations (24 h) and behavioral abnormalities (72 h). After 72 h of exposure to DBP, microglia in the brain were over-activated, reactive oxygen species (ROS) formation was increased, and apoptosis was observed. Meanwhile, it was found that neurons exhibited impaired mitochondrial structure, absent mitochondrial membrane potential and up-regulated autophagy. Further comprehensive biochemical analyses and RNA-Seq, validated by RT-qPCR, glutamate metabolism and PPAR signaling pathway were significantly enriched in the DBP stress group, this may be the main reason for the disruption of glycolysis/gluconeogenesis processes and the reduction of energy substrates for the astrocyte-neuron lactate shuttle (ANLS). In addition, the DBP-exposed group showed aberrant activation of endoplasmic reticulum (ER) stress signaling pathway, which may be related to ROS as well as neuronal apoptosis and autophagy. In conclusion, DBP-induced neurotoxicity may be the combined result of insufficient neuronal energy acquisition, damage to mitochondrial structure, apoptosis and autophagy. These results provide a theoretical basis for understanding the neurotoxic effects of DBP.

Brain targeted lactoferrin coated lipid nanocapsules for the combined effects of apocynin and lavender essential oil in PTZ induced seizures

Apocynin (APO) is a plant derived antioxidant exerting specific NADPH oxidase inhibitory action substantiating its neuroprotective effects in various CNS disorders, including epilepsy. Due to rapid elimination and poor bioavailability, treatment with APO is challenging. Correspondingly, novel APO-loaded lipid nanocapsules (APO-LNC) were formulated and coated with lactoferrin (LF-APO-LNC) to improve br ain targetability and prolong residence time. Lavender oil (LAV) was incorporated into LNC as a bioactive ingredient to act synergistically with APO in alleviating pentylenetetrazol (PTZ)-induced seizures. The optimized LF-APO-LAV/LNC showed a particle size 59.7 ± 4.5 nm with narrow distribution and 6.07 ± 1.6mV zeta potential) with high entrapment efficiency 92 ± 2.4% and sustained release (35% in 72 h). Following subcutaneous administration, LF-APO-LAV/LNC brought about ⁓twofold increase in plasma AUC and MRT compared to APO. A Log BB value of 0.2 ± 0.14 at 90 min reflects increased brain accumulation. In a PTZ-induced seizures rat model, LF-APO-LAV/LNC showed a Modified Racine score of 0.67 ± 0.47 with a significant increase in seizures latency and decrease in duration. Moreover, oxidant/antioxidant capacity and inflammatory markers levels in brain tissue were significantly improved. Histopathological and immunohistochemical assessment of brain tissue sections further supported these findings. The results suggest APO/LAV combination in LF-coated LNC as a promising approach to counteract seizures.

Assessment of wound healing activity in diabetic mice treated with a novel therapeutic combination of selenium nanoparticles and platelets rich plasma

Diabetic wound healing is sluggish, often ending in amputations. This study tested a novel, two-punch therapy in mice-Selenium nanoparticles (Se NPs) and platelet-rich plasma (PRP)-to boost healing. First, a mouse model of diabetes was created. Then, Se NPs were crafted for their impressive antioxidant and antimicrobial powers. PRP, packed with growth factors, was extracted from the mice's blood. Wound healing was tracked for 28 days through photos, scoring tools, and tissue analysis. Se NPs alone spurred healing, and PRP added extra fuel. Furthermore, when used in combination with PRP, the healing process was accelerated due to the higher concentration of growth factors in PRP. Notably, the combination of Se NPs and PRP exhibited a synergistic effect, significantly enhancing wound healing in diabetic mice. These findings hold promise for the treatment of diabetic wounds and have the potential to reduce the need for lower limb amputations associated with diabetic foot ulcers. The innovative combination therapy using Se NPs and PRP shows great potential in expediting the healing process and addressing the challenges of impaired wound healing in individuals with diabetes. This exciting finding suggests this therapy could change diabetic wound management, potentially saving limbs and improving lives.

Maternal exposure to di-(2-ethylhexyl) phthalate impaired the social interaction via activating microglia in male pups

Di-(2-ethylhexyl) phthalate (DEHP), a common endocrine-disrupting chemical (EDC), is widely used in daily articles, early exposure to DEHP is associated with many behavioral changes in pups. This study aimed to investigate the effects and underlying mechanisms of maternal exposure to DEHP on the impaired social interaction in pups. Pregnant rats were administered 0, 30, 300, or 750 mg/kg/d DEHP daily by oral gavage. Highly aggressive proliferating immortalized (HAPI) cells were treated with mono-(2-ethylhexyl) phthalate (MEHP) and tyrosine phosphorylation inhibitor (AG490). Our results showed that DEHP exposure induced the activation of microglias (MGs) via activating the janus kinase 2 / signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway, and increased the level of pro-inflammatory factors, then impaired the social behavior in male pups, but not female pups. Moreover, MEHP exposure could also activate HAPI via activating this signaling pathway, and AG490 could inhibit the activation of this signaling pathway caused by MEHP. Therefore, we indicated that maternal exposure to DEHP could cause the gender-specific impaired social interaction in pups that might be related to the activation of MGs.

Prenatal exposures to phthalates and bisphenols in relation to oxidative stress: single pollutant and mixtures analyses

Prenatal exposures to phthalates and bisphenols have been shown to be linked with adverse birth outcomes. Oxidative stress (OS) is considered a potential mechanism. The objective of this study was to explore the individual and mixtures of prenatal exposures to phthalates and bisphenols in associations with OS biomarkers. We measured eight phthalate metabolites and three bisphenols in the urine samples from 105 pregnant women in Wuhan, China. Urinary 8-hydroxydeoxyguanosine (8-OHdG), 8-isoprostaglandin F2α (8-isoPGF2α), and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) were determined as OS biomarkers. The OS biomarkers in associations with the individual chemicals were estimated by linear regression models and restricted cubic spline (RCS) models, and their associations with the chemical mixtures were explored by quantile g-computation (qg-comp) models. In single-pollutant analyses, five phthalate metabolites including monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-(2-ethylhexyl) phthalate (MEHP), (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) were positively associated with urinary 8-OHdG levels (all FDR-adjusted P = 0.06). These associations were further confirmed by the RCS models and were linear (P for overall association ≤ 0.05 and P for non-linear association > 0.05). In mixture analyses, qg-comp models showed that a one-quartile increase in the chemical mixtures of phthalate metabolites and bisphenols was positively associated with urinary levels of 8-OHdG and 8-isoPGF2α, and bisphenol A (BPA) and bisphenol F (BPF) were the most contributing chemicals, respectively. Prenatal exposures to individual phthalates and mixtures of phthalates and bisphenols were associated with higher OS levels.

Integrated transcriptomic and biochemical characterization of the mechanisms governing stress responses in soil-dwelling invertebrate (Folsomia candida) upon exposure to dibutyl phthalate

Dibutyl phthalate (DBP) is one of the most commonly utilized plasticizers and a frequently detected phthalic acid ester (PAE) compound in soil samples. However, the toxicological effects of DBP on soil-dwelling organisms remain poorly understood. This study employed a multi-biomarker approach to investigate the impact of DBP exposure on Folsomia candida's survival, reproduction, enzyme activity levels, and transcriptional profiles. Analyses of antioxidant biomarkers, including catalase (CAT) and glutathione S-transferase (GST), as well as detoxifying enzymes such as acetylcholinesterase (AChE), Cytochrome P450 (CYP450), and lipid peroxidation (LPO), revealed significant increases in CAT activity, GST levels, and CYP450 expression following treatment with various doses of DBP for 2, 4, 7, or 14 days. Additionally, LPO induction was observed along with significant AChE inhibition. In total, 3175 differentially expressed genes (DEGs) were identified following DBP treatment that were enriched in six Gene Ontology (GO) terms and 144 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including 85 upregulated and 59 downregulated primarily associated with lipid metabolism, signal transduction, DNA repair, and cell growth and death. Overall these results provide foundational insights for further research into the molecular mechanisms underlying responses of soil invertebrates to DBP exposure.

Effects of Dibutylphthalate and Steroid Hormone Mixture on Human Prostate Cells

Phthalates are a family of aromatic chemical compounds mainly used as plasticizers. Among phthalates, di-n-butyl phthalate (DBP) is a low-molecular-weight phthalate used as a component of many cosmetic products, such as nail polish, and other perfumed personal care products. DBP has toxic effects on reproductive health, inducing testicular damage and developmental malformations. Inside the male reproductive system, the prostate gland reacts to both male and female sex steroids. For this reason, it represents an important target of endocrine-disrupting chemicals (EDCs), compounds that are able to affect the estrogen and androgen signaling pathways, thus interfering with prostate homeostasis and inducing several prostate pathologies. The aim of this project was to investigate the effects of DBP, alone and in combination with testosterone (T), 17β-estradiol (E2), and both, on the normal PNT1A human prostate cell-derived cell line, to mimic environmental contamination. We showed that DBP and all of the tested mixtures increase cell viability through activation of both estrogen receptor α (ERα) and androgen receptor (AR). DBP modulated steroid receptor levels in a nonmonotonic way, and differently to endogenous hormones. In addition, DBP translocated ERα to the nucleus over different durations and for a more prolonged time than E2, altering the normal responsiveness of prostate cells. However, DBP alone seemed not to influence AR localization, but AR was continuously and persistently activated when DBP was used in combination. Our results show that DBP alone, and in mixture, alters redox homeostasis in prostate cells, leading to a greater increase in cell oxidative susceptibility. In addition, we also demonstrate that DBP increases the migratory potential of PNT1A cells. In conclusion, our findings demonstrate that DBP, alone and in mixtures with endogenous steroid hormones, acts as an EDC, resulting in an altered prostate cell physiology and making these cells more prone to cancer transformation.

Maternal exposure to dibutyl phthalate regulates MSH6 crotonylation to impair homologous recombination in fetal oocytes

Homologous recombination (HR) during early oogenesis repairs programmed double-strand breaks (DSBs) to ensure female fertility and offspring health. The exposure of fetal ovaries to endocrine disrupting chemicals (EDCs) can cause reproductive disorders in the adulthood. The EDC dibutyl phthalate (DBP) is widely distributed in flexible plastic products, leading to ubiquitous human exposure. Here, we report that maternal exposure to DBP caused gross aberrations in meiotic prophase I of fetal oocytes, including delayed progression, impaired DNA damage response, uncoupled localization of DMC1 and RAD51, and decreased HR. However, programmed DSBs were efficiently repaired. DBP exposure negatively regulated lysine crotonylation (Kcr) of MSH6. Similar meiotic defects were observed in fetal ovaries with targeted disruption of Msh6, and mutation of K544cr of MSH6 impaired its association with Ku70, thereby promoting non-homologous end joining (NHEJ) and inhibiting HR. Unlike mature F1 females, F2 female mice exhibited premature follicular activation, precocious puberty, and anxiety-like behaviors. Therefore, DBP can influence early meiotic events, and Kcr of MSH6 may regulate preferential induction of HR or NHEJ for DNA repair during meiosis.

Transcriptional analysis in peripheral blood cells of individuals with elevated phthalate exposure - Results of the EuroMix study

Exposure to phthalates is widespread in Europe. Phthalates are considered endocrine disrupting compounds and are classified as toxic for reproduction. However how phthalates affect the transcriptome in humans remains largely unknown. To investigate the effects of phthalate exposure on the transcriptomic profile we conducted RNA sequencing on peripheral blood samples from the Norwegian EuroMix cohort. We compared gene expression changes between participants with high, medium, and low exposure of six phthalates and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH). Comparing high and low exposure groups, DINCH was the compound that showed the highest number of differentially expressed genes (126 genes) followed by mono-n-butyl phthalate (MnBP; 89 genes) and mono-iso-nonyl phthalate (MiBP; 70 genes). Distributions between up- or down-regulated genes were similar across the different phthalates and DINCH. All phthalates including DINCH shared common differentially expressed genes ranging from 3 to 37 overlaps. Enriched Gene Ontology (GO) and biological pathway analysis revealed that most of the differentially expressed genes were associated with general cellular metabolism GO terms. MnBP and DINCH, particularly, showed a marked enrichment in various immunological function pathways including neutrophil degranulation, adaptive immune system and signaling by interleukins. Furthermore, the association between genes involved in the peroxisome proliferator activated receptor (PPAR) signaling pathway and phthalates, including DINCH, was evaluated. In total, 15 genes showed positive or negative associations across 5 phthalates and DINCH. MnBP and MiBP were the phthalate metabolites with the highest number of associations: 8 and 4 PPAR signaling pathway genes, respectively. Overall, we have performed an association study between phthalate exposure levels and modulation of transcriptomic profiles in human peripheral blood cells. DINCH, which is often mentioned as a substitute for phthalates, had comparable effects on differential gene expression in peripheral blood cells as phthalates.

Neuro-protective potentials of N-acetylcysteine and zinc against di(2-ethylhexyl)-phthalate-induced neuro-histopathology and dys-regulations of Dopamine and Glutamate in rat brain

This study examined neuro-protective potentials of N-acetyl-cysteine (NAC) and Zinc on expression levels of Dopamine and Glutamate in the Cerebrum, Hypothalami and Pituitary Glands in Di(2-ethylhexyl)-phthalate (DEHP)-induced neurotoxicity in rats. Thirty-six adult male Wistar rats were randomly divided into 6 groups (n = 6). Group 1 was control. Groups 2-6 received oral administrations of 100 mg/kg NAC, 0.5 mg/kg Zinc, 750 mg/kg DEHP, DEHP + NAC doses and DEHP + Zinc doses respectively for 21 days. Brain histology (Heamatoxyline and Eosine technique), histochemical and enzyme-linked-immunosorbent assays of Dopamine and Glutamate in homogenates of Cerebrum, Hypothalami and Pituitary Glands were evaluated. Data were statistically analyzed using One-way-ANOVA with Tukey-post-hoc test at p ≤ 0.05. Histo-pathological evaluations of Cerebrum, Hypothalami and Pituitary Glands showed gross histo-alterations and neurodegenerative changes (Group 4), mild histo- and neuro-degenerative changes (Groups 5 and 6) and normal histology (Group 1). Histochemical analyses showed higher Dopamine levels in Hypothalami (Group 5) and Pituitary Glands (Groups 5 and 6), compared with Group 4. Furthermore, results showed lower Glutamate levels in Cerebrum, Hypothalami and Pituitary Glands of Groups 5 and 6, compared with Group 4. Overall, NAC and Zinc conferred neuro-protection and histo-protection against DEHP-induced neuro-toxicity, neuro-histopathology, decreased Dopamine levels and increased Glutamate levels.

Toxicity of dibutyl phthalate to pakchoi (Brassica campestris L.): Evaluation through different levels of biological organization

Dibutyl phthalate (DBP) is a typical persistent organic pollutant with a high load in the agricultural soils of vegetable crops. Currently, studies on the toxicity of DBP in vegetable crops are limited. Therefore, in this study, pakchoi (Brassica campestris L.), a typical vegetable crop, was used to evaluate the toxic effects of DBP. Pakchoi was exposed to DBP for 24 d at three doses (2, 20, and 200 mg/kg), and the phenotypic, biochemical, and molecular indicators were determined. The results revealed that DBP could reduce the emergence of pakchoi and inhibit plant height, root length, fresh weight, and leaf area. At the biochemical level, DBP exposure could reduce the content of three typical photosynthetic pigments (chlorophyll a and b and carotenoids). The effects of DBP exposure on the quality of pakchoi were primarily through reduced soluble sugar and increased proline contents. In addition, O₂·^- and H₂O₂ levels increased after DBP stress, and the corresponding antioxidant enzymes (SOD, POD, and CAT) were activated to resist oxidative damage. The dose- and time-dependent toxicities of DBP to pakchoi were demonstrated using an integrated biological response index. Finally, the molecular-level results on Day 24 showed that the three antioxidant enzyme genes (sod, pod, and cat) were significantly downregulated, and the antioxidant enzyme genes were more sensitive biomarkers than the enzyme activities. However, the expression level of enzyme genes was opposite to that of enzyme activity (SOD and POD); thus, DBP might directly interact with these enzymes. Molecular docking showed that DBP could stably bind near the SOD/POD active center through intermolecular interaction forces. This study provides essential information on the risk of DBP toxicity to vegetable crops.

Single-cell atlas of keratoconus corneas revealed aberrant transcriptional signatures and implicated mechanical stretch as a trigger for keratoconus pathogenesis

Keratoconus is a common ectatic corneal disorder in adolescents and young adults that can lead to progressive visual impairment or even legal blindness. Despite the high prevalence, its etiology is not fully understood. In this study, we performed single-cell RNA sequencing (scRNA-Seq) analysis on 39,214 cells from central corneas of patients with keratoconus and healthy individuals, to define the involvement of each cell type during disease progression. We confirmed the central role of corneal stromal cells in this disease, where dysregulation of collagen and extracellular matrix (ECM) occurred. Differential gene expression and histological analyses revealed two potential novel markers for keratoconus stromal cells, namely CTSD and CTSK. Intriguingly, we detected elevated levels of YAP1 and TEAD1, the master regulators of biomechanical homeostasis, in keratoconus stromal cells. Cyclical mechanical experiments implicated the mechanical stretch in prompting protease production in corneal stromal cells during keratoconus progression. In the epithelial cells of keratoconus corneas, we observed reduced basal cells and abnormally differentiated superficial cells, unraveling the corneal epithelial lesions that were usually neglected in clinical diagnosis. In addition, several elevated cytokines in immune cells of keratoconus samples supported the involvement of inflammatory response in the progression of keratoconus. Finally, we revealed the dysregulated cell-cell communications in keratoconus, and found that only few ligand-receptor interactions were gained but a large fraction of interactional pairs was erased in keratoconus, especially for those related to protease inhibition and anti-inflammatory process. Taken together, this study facilitates the understanding of molecular mechanisms underlying keratoconus pathogenesis, providing insights into keratoconus diagnosis and potential interventions.

Maternal DBP exposure promotes synaptic formation in offspring by activating astrocytes via the AKT/NF-κB/IL-6/JAK2/STAT3 signaling pathway

It has been demonstrated that activated astrocytes in the hypothalamus could disrupt GnRH secretion in offspring after maternal di-n-butyl phthalate (DBP) exposure, indicating that the effect of DBP on astrocyte activation and crosstalk between astrocytes and neurons is still worthy of further investigation. In this study, pregnant mice were intragastrically administered DBP dissolved in corn oil from gestational days (GD) 12.5-21.5. Maternal DBP exposure resulted in hippocampal astrocyte activation, abnormal synaptic formation, and reduced autonomic and exploratory behavior in offspring on postnatal day (PND) 22. Further studies identified that mono-n-butyl phthalate (MBP) induced astrocyte activation and proliferation by activating the AKT/NF-κB/IL-6/JAK2/STAT3 signaling pathway. Moreover, upregulated thrombospondin 1 (TSP1) in activated astrocytes regulated synaptic-related protein expression. This study highlights the neurotoxicity of maternal DBP exposure to offspring, which provides new insights into identifying potential molecular targets for the treatment of diseases related to neurological development disorders in children.

Disruption of the blood-brain barrier and its close environment following adult exposure to low doses of di(2-ethylhexyl)phthalate alone or in an environmental phthalate mixture in male mice

We have previously shown that adult male mice exposure to low doses of di(2-ethylhexyl)phthalate (DEHP) alters neural function and behaviour. Whether such exposure also affects the integrity and function of the blood-brain barrier (BBB) remained to be explored. The impact of adult exposure to low doses of DEHP alone or in an environmental phthalate mixture on the BBB integrity and surrounding parenchyma was studied in male mice. Two-month-old C57BL/6J males were orally exposed for 6 weeks to DEHP alone (5, and 50 μg/kg/day) or to DEHP (5 μg/kg/day) in an environmental phthalate mixture. BBB permeability, glial activation and neuroinflammation were investigated in the hypothalamic medial preoptic area (mPOA) and hippocampus involved, respectively on the reproductive and cognitive functions. Exposure to DEHP alone or in a phthalate mixture increased BBB permeability and affected the endothelial accessory tight junction protein zona occludens-1 and caveolae protein Cav-1 in the mPOA and the hippocampal CA1 and CA3 areas. This was associated with an inflammatory profile including astrocyte activation accompanied by enhanced expression of inducible nitric oxide synthase in the mPOA, and a microglial activation in the mPOA and the hippocampal CA1 and CA3 areas. The protein levels of the inflammatory molecule cyclooxygenase-2 were increased in activated microglial cells of the exposed mPOA. None of the major effects induced by DEHP alone or in a mixture was detected in the hippocampal dendate gyrus. The data highlight that environmental exposure to endocrine disruptors such as phthalates, could represent a risk factor for the cerebrovascular function.

Possible Role of Kaempferol in Reversing Oxidative Damage, Inflammation, and Apoptosis-Mediated Cortical Injury Following Cadmium Exposure

Cadmium (Cd) is a heavy metal of considerable toxicity, inducing a number of hazardous effects to humans and animals including neurotoxicity. This experiment was aimed to investigate the potential effect of kaempferol (KPF) against Cd-induced cortical injury. Thirty-two adult Sprague-Dawley rats were divided equally into four groups. The control rats intraperitoneally (i.p.) injected with physiological saline (0.9% NaCl), the cadmium chloride (CdCl2)-treated rats were i.p. injected with 4.5 mg/kg of CdCl2, the KPF-treated rats were orally gavaged with 50 mg/kg of KPF, and the KPF + CdCl2-treated rats were administered orally 50 mg/kg of KPF 120 min before receiving i.p. injection of 4.5 mg/kg CdCl2. CdCl2 exposure for 30 days led to the accumulation of Cd in the cortical tissue, accompanied by a reduction in the content of monoamines and acetylcholinesterase activity. Additionally, CdCl2 induced a state of oxidative stress as evidenced by the elevation of lipid peroxidation and nitrate/nitrite levels, while glutathione content and the activities of glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase were decreased. Moreover, CdCl2 mediated inflammatory events in the cortical tissue through increasing tumor necrosis factor-alpha and interleukin-1 beta levels and upregulating the expression of inducible nitric oxide synthase. Furthermore, pro-apoptotic proteins (Bax and caspase-3) were elevated, while Bcl-2, the anti-apoptotic protein, was decreased. Also, histological alterations were observed obviously following CdCl2. However, KPF pretreatment restored significantly the examined markers to be near the normal values. Hence, the obtained data provide evidences that KPF pretreatment has the protective effect to preserve the cortical tissues in CdCl2-exposed rats by restraining oxidative stress, inflammatory response, apoptosis, neurochemical modulation, and improving the histological changes.

Effects of Di-Isononyl Phthalate (DiNP) on Follicular Atresia in Zebrafish Ovary

Di-isononyl phthalate (DiNP) is a plasticizer reported to elicit hormone-like activity and disrupt metabolism and reproduction in fish and other vertebrates. In general, phthalates have been used at high concentrations beyond reported environmental levels to assess their adverse effects on fish gonadal physiology. The present study exposed adult female zebrafish to a wide range of DiNP concentrations [0.42 µg L^-1 (10^-9 M), 4.2 µg L^-1 (10^-8 M), and 42 µg L^-1 (10^-7 M)] for 21 days. We evaluated gene expression profiles related to apoptosis, autophagy, and oxidative stress; DNA fragmentation (TUNEL assay: terminal deoxynucleotidyl transferase dUTP nick end labeling) and caspase activity (CAS3) were also examined. Exposure to 0.42 and 4.2 µg L^-1 upregulated the genes coding for tnfa and baxa, sod1, prkaa1, respectively. CAS3 immunohistochemistry revealed a higher number of positive vitellogenic oocytes in ovaries exposed to 0.42 µg L^-1. Subsequently, we examined the relationship between CAS3 signaling and DNA fragmentation. Accordingly, DNA fragmentation was observed in vitellogenic follicles of fish exposed to 0.42 and 4.2 μg L^-1. Our results demonstrate that follicular atresia can occur after exposure to environmental levels of DiNP for 21 days, which may adversely affect the reproductive performance of female zebrafish in a non-monotonic manner.

Selenium Nanoparticles Pre-Treatment Reverse Behavioral, Oxidative Damage, Neuronal Loss and Neurochemical Alterations in Pentylenetetrazole-Induced Epileptic Seizures in Mice

Introduction

Epilepsy is a chronic neurological condition characterized by behavioral, molecular, and neurochemical alterations. Current antiepileptic drugs are associated with various adverse impacts. The main goal of the current study is to investigate the possible anticonvulsant effect of selenium nanoparticles (SeNPs) against pentylenetetrazole (PTZ)-mediated epileptic seizures in mice hippocampus. Sodium valproate (VPA) was used as a standard anti-epileptic drug.

Methods

Mice were assigned into five groups (n=15): control, SeNPs (5 mg/kg, orally), PTZ (60 mg/kg, intraperitoneally), SeNPs+PTZ and VPA (200 mg/kg)+PTZ. All groups were treated for 10 days.

Results

PTZ injection triggered a state of oxidative stress in the hippocampal tissue as represented by the elevated lipoperoxidation, heat shock protein 70 level, and nitric oxide formation while decreased glutathione level and antioxidant enzymes activity. Additionally, the blotting analysis showed downregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in the epileptic mice. A state of neuroinflammation was recorded following the developed seizures represented by the increased pro-inflammatory cytokines. Moreover, neuronal apoptosis was recorded following the development of epileptic convulsions. At the neurochemical level, acetylcholinesterase activity and monoamines content were decreased in the epileptic mice, accompanied by high glutamate and low GABA levels in the hippocampal tissue. However, SeNP supplementation was found to delay the onset and decreased the duration of tonic, myoclonic, and generalized seizures following PTZ injection. Moreover, SeNPs were found to provide neuroprotection through preventing the development of oxidative challenge via the upregulation of Nrf2 and HO-1, inhibiting the inflammatory response and apoptotic cascade. Additionally, SeNPs reversed the changes in the activity and levels of neuromodulators following the development of epileptic seizures.

Conclusion

The obtained results suggest that SeNPs could be used as a promising anticonvulsant drug due to its potent antioxidant, anti-inflammatory, and neuromodulatory activities.

Berberine mitigates oxidative damage associated with testicular impairment following mercury chloride intoxication

In this study, we assessed the protective effect of berberine (BBR) against mercuric chloride (HgCl₂)-induced reproductive impairment. Twenty-eight adult male Wistar albino rats were placed into four equal groups: control, BBR, HgCl₂, and BBR + HgCl₂. All the treatments were orally administered for seven consecutive days. The rats exposed to HgCl₂ showed a marked decrease in testosterone accompanied by an increase in lipid peroxidation (LPO) and nitric oxide (NO). Additionally, HgCl₂ decreased glutathione (GSH) content, deactivated catalase (CAT) and glutathione reductase (GR), and suppressed the activities and mRNA expression of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the testicular tissue. In addition, histological deformations and testicular cell loss were recorded, as evidenced by the upregulation of caspase-3 following HgCl₂ intoxication. Notably, BBR administration reversed the testicular impairments associated with HgCl₂ exposure. These findings suggest that BBR protected the testicular tissue following HgCl₂ exposure through inhibiting the disturbance in the testosterone level and enhanced the antioxidant capacity. PRACTICAL APPLICATIONS: Heavy metals are naturally existing metallic elements in the earth's crust. These trace metals have the potential to cause multiple adverse reactions to the living systems, even at low exposure doses. Human exposure may also result from industrial, agricultural, and domestic activities. Berberine (BBR, a naturally occurring quaternary benzylisoquinoline alkaloid) is a protoberberine and is the representative main active ingredient in all parts of Berberis species. BBR has been used widely in folk medicine worldwide for its multiple pharmacological and therapeutic activities; for example, in the treatment of digestive and reproductive system disorders, microorganism infections, hemorrhage and wound healing, and cardiovascular and ophthalmic diseases. We found that BBR administration was able to abrogate significantly the reproductive toxicity associated with Hg intoxication. This protective effect comes from its strong antioxidant, anti-inflammatory, and antiapoptotic activities; suggesting that BBR may be applied to alleviate reproductive toxicity associated with Hg intoxication.

Biopesticide emamectin benzoate in the liver of male mice: evaluation of oxidative toxicity with stress protein, DNA oxidation, and apoptosis biomarkers

Emamectin benzoate (EMB), which is used as a pesticide in agriculture, household, and veterinary medicine, can cause tissue damage with oxidative toxicity and can be considered as inducing apoptosis. In the present study, male mice were conducted by oral administration in EMB doses 25, 50, and 100 (mg/kg/day) for 14 days. Glutathione (GSH) and thiobarbituric acid reactive substance (TBARS) levels using spectrophotometric methods were measured. 8-hydroxy-2'-deoxyguanosine (8-OHdG) which is DNA oxidation biomarker and, stress protein (HSP70) levels, caspase 3 enzyme activities were measured by ELISA techniques. This study shows that in vivo administration of EMB caused a marked induction of oxidative damage in liver tissue as demonstrated by an increased level of TBARS and reduced GSH level. The increase in HSP70 level did not prevent the apoptosis caused by the increase of caspase 3 enzyme activity. Toxicity caused by EMB also showed the formation of genotoxicity with an increase in DNA oxidation biomarker 8-OHdG levels. As a result of the study, the effects of toxicity caused by EMB on lipid; protein; and DNA, structural macromolecules in cells, and the importance of enzymatic and non-enzymatic bonds of the cell's protective systems were determined. Consequently, under experimental conditions, EMB exposure caused toxicity in the liver of male mice, and significant adverse effects were determined with biomarkers.

Nephroprotective Role of Selenium Nanoparticles Against Glycerol-Induced Acute Kidney Injury in Rats

Acute kidney injury (AKI) is a clinical syndrome associated with the incidence of rhabdomyolysis (RM). The current study was carried out to evaluate whether selenium nanoparticles (SeNPs) can protect against the glycerol-induced AKI model. Rats were distributed into four equal groups (n = 7): the control group (G1), SeNPs group (G2), AKI group (G3), and SeNPs+AKI group (G4). Rats in G1 were intramuscularly injected with physiological saline (0.9% NaCl). Rats in G2 were gavaged with SeNPs (0.1 mg/kg) for 14 days. Rats in G3 were intramuscularly injected with 50% glycerol (10 ml/kg). Rats in G4 were administered with SeNPs for 14 days and then injected with glycerol, as in G3. Glycerol-injected rats showed a significant increase in the kidney relative weight, as well as in the serum urea, creatinine, Kim-1, and renal malondialdehyde, nitric oxide, TNF-α, IL-1β, cytochrome c, Bax, and caspase-3 levels. In addition, a significant decrease in glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase was recorded in the renal tissue. Selenium nanoparticles reduced the biochemical, molecular, and histological changes produced by glycerol. Overall, our results suggest that selenium nanoparticles could be used to protect against AKI development via antioxidant, anti-inflammatory, and anti-apoptotic activities.

Use of Bacillus-siamensis-inoculated biochar to decrease uptake of dibutyl phthalate in leafy vegetables

Dibutyl phthalate (DBP) is a frequently detected farmland contaminant that is harmful to the environment and human health. In this study, a DBP-degrading endophytic Bacillus siamensis strain T7 was immobilized in rice husk-derived biochar for bioremediation of DBP-polluted agricultural soils. The effects of this microbe-biochar composite on the soil prokaryotic community and the mechanism by which it regulates DBP degradation, were also investigated. A supplement of T7-biochar composite not only significantly boosted DBP biodegradation in soil by raising the DBP degradation rate constant and half-life from 0.1979 d^-1 and 2.3131 d to 0.2434 d^-1 and 2.1062 d, respectively, but also impeded DBP uptake by leafy vegetables. The general bioremediation effect of T7-biochar alliance excelled pure T7 suspensions and biochar, by trapping more DBP and boosting its complete degradation in soil. Besides, the combination of strain T7 and biochar can increase the proportion of some beneficial bacteria and boost the functional diversity of soil prokaryotic community, then to a certain extent may reverse the negative effect of DBP pollution on the agricultural soils. These results indicate that the rice-husk-derived biochar is a proper media when utilizing functional microbes into environmental treatment. Overall, T7-biochar composite is a promising soil modifier for soil bioremediation and the production of DBP-free crops.

Nephroprotective Role of Beta vulgaris L. Root Extract against Chlorpyrifos-Induced Renal Injury in Rats

Organophosphorus pesticides (OPs) are widely used for agricultural and housekeeping purposes. Exposure to OPs is associated with the progression of several health issues. Antioxidant agents may be powerful candidates to minimise adverse reactions caused by OPs. The aim of the present study was to evaluate the nephroprotective effects of red beetroot extract (RBR) against chlorpyrifos- (CPF-) induced renal impairments. CPF induced kidney dysfunction, as demonstrated by changes in serum creatinine and urea levels. Moreover, CPF exposure induced oxidative stress in the kidneys as determined by increased malondialdehyde and nitric oxide levels, decreased glutathione content, decreased catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase activities, and decreased nuclear factor (erythroid-derived 2)-like-2 factor expression. In addition, CPF induced inflammation in renal tissue as evidenced by increased release of tumor necrosis factor-alpha and interleukin-1β and upregulation of inducible nitric oxide synthase. Furthermore, CPF promoted cell death as demonstrated by decreased Bcl-2 and increased Bax and caspase-3 levels. Treatment with RBR one hour prior to CPF treatment blocked the effects observed in response to CPF alone. Our results suggest that RBR could be used to alleviate CPF-induced nephrotoxicity through antioxidant, anti-inflammatory, and antiapoptotic activities.

Dibutyl phthalate-mediated oxidative stress induces splenic injury in mice and the attenuating effects of vitamin E and curcumin

Dibutyl phthalate (DBP) is a ubiquitous environmental contaminant that at certain levels can be harmful to human health. Although DBP has been widely linked to immunotoxicity, any association between DBP exposure and splenic injury remains unknown. The purpose of this study was to investigate whether DBP exposure can induce splenic injury and the antagonistic effects of two antioxidants, vitamin E (VitE) and curcumin (Cur), on DBP-induced splenic injury. The levels of ROS, GSH, T-AOC, IL-1β, TNF-α, cytochrome C, caspase-8, caspase-9 and caspase-3 in the spleen homogenate of mice were measured. Any histopathological changes in the spleen were observed using H&E and toluidine blue staining. And the morphology of mitochondria was observed using Janus Green B staining. The results indicate that exposure to 50 mg/kg DBP could cause histopathological changes of the spleen and result in inflammation and apoptosis associated with oxidative stress, which may lead to splenic injury in mice. Moreover, both VitE and Cur could antagonize the oxidative stress induced by DBP to reduce splenic injury. These findings help to expand our understanding of DBP-mediated immunotoxicity, and to show that VitE and Cur can alleviate DBP-induced splenic injury and the possible DBP-associated decline in immune function.

The Neuroprotective Role of Coenzyme Q10 Against Lead Acetate-Induced Neurotoxicity Is Mediated by Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities

Heavy metal exposure, in lead (Pb) particularly, is associated with severe neuronal impairment though oxidative stress mediated by reactive oxygen species, and antioxidants may be used to abolish these adverse effects. This study investigated the potential neuroprotective role of coenzyme Q10 (CoQ₁₀) against lead acetate (PbAc)-induced neurotoxicity. Twenty-eight male Wistar albino rats were divided into four equal groups (n = 7) and treated as follows: the control group was injected with physiological saline (0.9% NaCl); the CoQ₁₀ group was injected with CoQ₁₀ (10 mg/kg); PbAc group was injected with PbAc (20 mg/kg); PbAc + CoQ₁₀ group was injected first with PbAc, and after 1 h with CoQ₁₀. All groups were injected intraperitoneally for seven days. PbAc significantly increased cortical lipid peroxidation, nitrate/nitrite levels, and inducible nitric oxide synthase expression, and decreased glutathione content, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activity and mRNA expression, as well as nuclear factor erythroid 2–related factor 2 (Nrf2) and homoxygenase-1 (HO-1) expression. PbAc also promoted the secretion of interleukin-1ß and tumor necrosis factor-α, inhibited interleukin-10 production, triggered the activation of pro-apoptotic proteins, and suppressed anti-apoptotic proteins. Additionally, PbAc increased the cortical levels of serotonin, dopamine, norepinephrine, GABA, and glutamate, and decreased the level of ATP. However, treatment with CoQ₁₀ rescued cortical neurons from PbAc-induced neurotoxicity by restoring the balance between oxidants and antioxidants, activating the Nrf2/HO-1 pathway, suppressing inflammation, inhibiting the apoptotic cascade, and modulating cortical neurotransmission and energy metabolism. Altogether, our findings indicate that CoQ₁₀ has beneficial effects against PbAc-induced neuronal damage through its antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory activities.