Effect of di(2-ethylhexyl) phthalate on Nrf2-regulated glutathione homeostasis in mouse kidney

Di (2-ethylhexyl) phthalate and polystyrene microplastics co-exposure caused oxidative stress to activate NF-κB/NLRP3 pathway aggravated pyroptosis and inflammation in mouse kidney

Polystyrene microplastic (PS-MPs) contamination has become a worldwide hotspot of concern, and its entry into organisms can cause oxidative stress resulting in multi-organ damage. The plasticizer di (2-ethylhexyl) phthalate (DEHP) is a common endocrine disruptor, these two environmental toxins often occur together, but their combined toxicity to the kidney and its mechanism of toxicity are unknown. Therefore, in this study, we established PS-MPS and/or DEHP-exposed mouse models. The results showed that alone exposure to both PS-MPs and DEHP caused inflammatory cell infiltration, cell membrane rupture, and content spillage in kidney tissues. There were also down-regulation of antioxidant enzyme levels, increased ROS content, activated of the NF-κB pathway, stimulated the levels of heat shock proteins (HSPs), pyroptosis, and inflammatory associated factors. Notably, the co-exposure group showed greater toxicity to kidney tissues, the cellular assay further validated these results. The introduction of the antioxidant n-acetylcysteine (NAC) and the NLRP3 inhibitor (MCC950) could mitigate the changes in the above measures. In summary, co-exposure of PS-MPs and DEHP induced oxidative stress that activated the NF-κB/NLRP3 pathway and aggravated kidney pyroptosis and inflammation, as well as that HSPs are also involved in this pathologic injury process. This study not only enriched the nephrotoxicity of plasticizers and microplastics, but also provided new insights into the toxicity mechanisms of multicomponent co-pollution in environmental.

Environmental toxicants and nephrotoxicity: Implications on mechanisms and therapeutic strategies

Kidneys are one of the most important organs in the human body. In addition to filtering 200 liters of fluid every 24 hours, the kidney also regulates acid-base balance, maintains electrolyte balance, and removes waste and toxicants from the body. Nephrotoxicity is the term used to describe the deterioration of kidney function caused by the harmful effects of medications and various types of environmental toxicants. Exposure to environmental toxicants is an inevitable side effect in the world's increasing industrialization and even more prevalent in underdeveloped nations. Growing data over the past few years has illuminated the probable connection between environmental toxicants and nephrotoxicity. Phthalates, microplastics, acrylamide and bisphenol A are environmental toxicants of particular concern, which are known to have nephrotoxic effects. Such toxicants may accumulate in the kidneys of humans after being consumed, inhaled, or come into contact with the skin. They can enter cells through endocytosis and accumulate in the cytoplasm. Small-sized nephrotoxicants can cause a variety of ailments including inflammation with increased production of pro-inflammatory cytokines, oxidative stress, mitochondrial dysfunction, autophagy, and apoptosis. This study uncovers the potential for new insights concerning the relationship between various environmental toxicants and kidney health. The objectives of this review is to establish information gaps, assess and identify the toxicity mechanisms of different nephrotoxicants, identify innovative pharmacological therapies that demonstrate promising therapeutic benefits/ relevance, and discuss the predictions for the future based on the analysis of the literature.

Recent advances in toxicological research of di-(2-ethylhexyl)-phthalate: Focus on endoplasmic reticulum stress pathway

The plasticizer di-(2-ethylhexyl)-phthalate (DEHP) is the most significant phthalate in production, usage, and environmental occurrence. DEHP is found in products such as personal care products, furniture materials, cosmetics, and medical devices. DEHP is noncovalently bind with plastic therefore, repeated uses lead to leaching out of it. Exposure to DEHP plasticizers leads to toxicity in essential organs of the body through various mechanisms. The main objective of this review article is to focus on the DEHP-induced endoplasmic reticulum (ER) stress pathway implicated in the testis, brain, lungs, kidney, heart, liver, and other organs. Not only ER stress, PPAR-related pathways, oxidative stress and inflammation, Ca2+ homeostasis disturbances in mitochondria are also identified as the relative mechanisms. ER is involved in various critical functions of the cell such as Protein synthesis, protein folding, calcium homeostasis, and lipid peroxidation but, DEHP exposure leads to augmentation of misfolded/unfolded protein. This review complies with various recently reported DEHP-induced toxicity studies and some pharmacological interventions that have been shown to be effective through ER stress pathway. DEHP exposure does assess health risks and vulnerability to populations across the globe. This study offers possible targets and approaches for addressing various DEHP-induced toxicity.

Hormetic Nutrition and Redox Regulation in Gut-Brain Axis Disorders

The antioxidant and anti-inflammatory effects of hormetic nutrition for enhancing stress resilience and overall human health have received much attention. Recently, the gut-brain axis has attracted prominent interest for preventing and therapeutically impacting neuropathologies and gastrointestinal diseases. Polyphenols and polyphenol-combined nanoparticles in synergy with probiotics have shown to improve gut bioavailability and blood-brain barrier (BBB) permeability, thus inhibiting the oxidative stress, metabolic dysfunction and inflammation linked to gut dysbiosis and ultimately the onset and progression of central nervous system (CNS) disorders. In accordance with hormesis, polyphenols display biphasic dose-response effects by activating at a low dose the Nrf2 pathway resulting in the upregulation of antioxidant vitagenes, as in the case of heme oxygenase-1 upregulated by hidrox® or curcumin and sirtuin-1 activated by resveratrol to inhibit reactive oxygen species (ROS) overproduction, microbiota dysfunction and neurotoxic damage. Importantly, modulation of the composition and function of the gut microbiota through polyphenols and/or probiotics enhances the abundance of beneficial bacteria and can prevent and treat Alzheimer's disease and other neurological disorders. Interestingly, dysregulation of the Nrf2 pathway in the gut and the brain can exacerbate selective susceptibility under neuroinflammatory conditions to CNS disorders due to the high vulnerability of vagal sensory neurons to oxidative stress. Herein, we aimed to discuss hormetic nutrients, including polyphenols and/or probiotics, targeting the Nrf2 pathway and vitagenes for the development of promising neuroprotective and therapeutic strategies to suppress oxidative stress, inflammation and microbiota deregulation, and consequently improve cognitive performance and brain health. In this review, we also explore interactions of the gut-brain axis based on sophisticated and cutting-edge technologies for novel anti-neuroinflammatory approaches and personalized nutritional therapies.

Sulforaphane protects from kidney damage during the release of unilateral ureteral obstruction (RUUO) by activating nuclear factor erythroid 2-related factor 2 (Nrf2): Role of antioxidant, anti-inflammatory, and antiapoptotic mechanisms

Releasing unilateral ureteral obstruction (RUUO) is the gold standard for decreasing renal damage induced during unilateral ureteral obstruction (UUO); however, the complete recovery after RUUO depends on factors such as the time and severity of obstruction and kidney contralateral compensatory mechanisms. Interestingly, previous studies have shown that kidney damage markers such as oxidative stress, inflammation, and apoptosis are present and even increase after removal obstruction. To date, previous therapeutic strategies have been used to potentiate the recovery of renal function after RUUO; however, the mechanisms involving renal damage reduction are poorly described and sometimes focus on the recovery of renal functionality. Furthermore, using natural antioxidants has not been completely studied in the RUUO model. In this study, we selected sulforaphane (SFN) because it activates the nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor that induces an antioxidant response, decreasing oxidative stress and inflammation, preventing apoptosis. Thus, we pre-administrated SFN on the second day after UUO until day five, where we released the obstruction on the three days after UUO. Then, we assessed oxidative stress, inflammation, and apoptosis markers. Interestingly, we found that SFN administration in the RUUO model activated Nrf2, inducing its translocation to the nucleus to activate its target proteins. Thus, the Nrf2 activation upregulated glutathione (GSH) content and the antioxidant enzymes catalase, glutathione peroxidase (GPx), and glutathione reductase (GR), which reduced the oxidative stress markers. Moreover, the improvement of antioxidant response by SFN restored S-glutathionylation in the mitochondrial fraction. Activated Nrf2 also reduced inflammation by lessening the nucleotide-binding domain-like receptor family pyrin domain containing 3 and interleukin 1β (IL-1β) production. Reducing oxidative stress and inflammation prevented apoptosis by avoiding caspase 3 cleavage and increasing B-cell lymphoma 2 (Bcl2) levels. Taken together, the obtained results in our study showed that the upregulation of Nrf2 by SFN decreases oxidative stress, preventing inflammation and apoptosis cell death during the release of UUO.

Evaluation of Bis(2-ethylhexyl) phthalate toxicity on the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9

Bis(2-ethylhexyl) phthalate, generally known as DEHP is a synthetic compound mainly used as a plasticizer to make polyvinyl chloride products flexible and soft. The present work aimed to study the toxicity of Bis(2-ethylhexyl) phthalate on the third instar larvae of transgenic Drosophila melanogaster(hsp70-lacZ) Bg9. The hsp70 gene is associated with the β-galactosidase in our present transgenic strain therefore, the more activity of β-galactosidase will indirectly correspond to hsp70 expression. The third instar larvae were allowed to feed on the diet for 24 h having 0.001, 0.005, 0.01, and 0.02 M of Bis(2-ethylhexyl) phthalate at the final concentration. After the exposure of 24hrs, the larvae were subjected to ONPG assay, X-gal staining, trypan blue exclusion test, oxidative stress markers assays, and comet assay. A dose-dependent increase in hsp70 expression, tissue damage, Glutathione-S-transferase (GST) activity, lipid peroxidation, monoamine oxidase, caspase-9 & 3, protein carbonyl content (PCC), DNA damage and decrease in the glutathione (GSH) content, delta-aminolevulinic acid dehydrogenase (ẟ-ALD-D) and acetylcholinesterase activity were observed in the larvae exposed to 0.005, 0.01, 0.02 M of Bis-(2-ethylhexyl) phthalate. The dose of 0.001 M of Bis(2-ethylhexyl) phthalate did not showed any toxic effects and hence can be considered as No Observed Adverse Effect Level (NOAEL) for Bis(2-ethylhexyl) phthalate. The study supports the use of Drosophila for the evaluation of possible toxic effects associated with synthetic compounds.

Sex-specific interactive effect of melamine and DEHP on a marker of early kidney damage in Taiwanese adults: A national population-based study from the Taiwan Biobank

Taiwan had the high incidence of chronic kidney disease (CKD) worldwide. Our objective was to examine associations between daily exposure of phthalates and melamine, two common nephrotoxins, and kidney damage risk in a well-established nationwide cohort. Study subjects were from Taiwan Biobank (TWB) with existing data of questionnaire and biochemical examinations. Average daily intake (ADI) levels of melamine and seven parental phthalates, including DEHP (di-2-ethylhexylphthalate), DiBP (Dibutyl phthalate), DnBP (Di-n-butyl phthalate), BBzP (Butyl benzyl phthalate), DEP (Diethyl phthalate), and DMP (Dimethyl phthalate) were estimated using a creatinine excretion-based model from urine melamine and 10 phthalate metabolites. Urine microalbumin to creatinine ratio (ACR) was used to represent for the outcome of kidney damage. Two statistical strategies were used: First, a weighted quantile sum (WQS) regression model to select the most important exposure variables of ADI levels of phthalates and melamine associated with ACR; Second, to examine effects of those most important exposure variables on ACR in multivariable linear regression models. In total, 1153 eligible adults were left for analyses. Of them, 591 (51.3%) and 562 (48.7%) were men and women, respectively, with a median age of 49 years old. By WQS, a significant and positive association was found between ADI of melamine and phthalates and ACR (β = 0.14, p = 0.002). ADI levels of melamine had the highest weight (0.57), followed by DEHP (0.13). Next, examining the two most important exposures in association with ACR, we found that the higher the melamine and DEHP intakes, the higher the ACR levels were found. An interaction effect was also found between melamine and DEHP intakes on urine ACR (p = 0.015). This result was more prominent in men (p = 0.008) than in women (p = 0.651). Environmental co-exposure of melamine and DEHP can potentially affect ACR in the community-dwelling Taiwanese adult population.

Effects of the in-utero dicyclohexyl phthalate and di-n-hexyl phthalate administration on the oxidative stress-induced histopathological changes in the rat liver tissue correlated with serum biochemistry and hematological parameters

Phthalates are widely used as plasticizers in the industry and are found in cosmetics, food and drink packaging, drugs, toys, households, medical devices, pesticides, personal care products, and paints. Phthalates exert endocrine disrupting and peroxisome proliferator effects in humans and wildlife associated with the pathogenesis of various diseases, including diabetes, obesity, infertility, cardiovascular diseases, metabolic syndrome, and cancer. Since phthalates are metabolized in the liver, which regulates the body's energy metabolism, long or short-term exposure to the phthalates is associated with impaired glucose, lipid, and oxidative stress metabolisms contributing to liver toxicity. However, the impact of in-utero exposure to DHP and DCHP on liver metabolism has not been studied previously. Thus, in this study, we evaluated serum biochemistry parameters, hematological markers, histopathological changes, and oxidative and pentose phosphate pathway (PPP) metabolisms in the liver following in-utero DHP and DCHP administration, respectively, in male and female rats. We found increased relative and absolute liver weights and impaired triglyceride, alanine transaminase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) levels upon dicyclohexyl phthalate (DCHP) and di-n-hexyl phthalate (DHP). Histopathological changes, including congestion, sinusoidal dilatation, inflammatory cell infiltration, cells with a pyknotic nucleus, lysis of hepatocytes, and degeneration of hepatic parenchyma have been observed in the liver samples of DHP and DCHP dose groups. Moreover, increased glutathione s-transferase (GST), glucose 6-phosphate dehydrogenase (G6PD), and glutathione reductase (GR) activities have been found in the liver samples of DHP and DCHP-treated rats associated with impaired pentose phosphate pathway (PPP) and oxidative stress metabolism. First time in the literature, we showed that in-utero exposure to DHP and DCHP causes liver damage associated with impaired oxidative stress metabolism in male and female rats. Our data may guide researchers and governments to regulate and restrict phthalates in industrial products.

The Relationship between Typical Environmental Endocrine Disruptors and Kidney Disease

Endocrine disrupting chemicals (EDCs) are exogenous substances that alter the endocrine function of an organism, to result in adverse effects on growth and development, metabolism, and reproductive function. The kidney is one of the most important organs in the urinary system and an accumulation point. Studies have shown that EDCs can cause proteinuria, affect glomeruli and renal tubules, and even lead to diabetes and renal fibrosis in animal and human studies. In this review, we discuss renal accumulation of select EDCs such as dioxins, per- and polyfluoroalkyl substances (PFAS), bisphenol A (BPA), and phthalates, and delineate how exposures to such EDCs cause renal lesions and diseases, including cancer. The regulation of typical EDCs with specific target genes and the activation of related pathways are summarized.

Exploring Nrf2 as a therapeutic target in testicular dysfunction

Testicular dysfunction, a major contributory factor to infertility, has received a lot of attention over the recent years. Several studies have linked abnormal sperm function and morphology with an enhanced generation of reactive oxygen species (ROS) and oxidative stress. The nuclear factor erythroid-derived 2 (Nrf2) is a transcriptional response to cellular stresses (intrinsic or extrinsic) that regulates the oxidative status, mitochondrial dysfunction, inflammation, and proteostasis. In this review, the therapeutic role of Nrf2 was explored. To do so, scientific data were retrieved from databases such as Elsevier, Wiley, Web of Science, Springer, PubMed, Taylor and Francis, and Google Scholar using search terms such as "Nrf2" and "testis," "sperm," "testicular function," and "testosterone." It has been noted that Nrf2 influences the physiology and pathology of testicular dysfunction, especially in the spermatogenic process, by regulating cellular resistance to oxidative stress, inflammation, and environmental toxicants. However, numerous compounds serve as activators and inhibitors of testicular Nrf2. Nrf2 activators might play a therapeutic role in the prevention and treatment of testicular dysfunction, while molecules that inhibit Nrf2 might induce dysfunction in testis components. Nrf2 activators protect cells against oxidative damage and activate Nrf2/KEAP1 signaling which promotes its movement to the nucleus, and increased Nrf2 function and expression, along with their downstream antioxidant gene. Nrf2 inhibitors facilitate oxidative stress via interfering with the Nrf2 signal pathway. The Nrf2 activation could serve as a promising therapeutic target for testicular dysfunction. This review explored the effect of Nrf2 on testicular function while highlighting potential activators and inhibitors of Nrf2.

Maternal Serum and Placental Metabolomes in Association with Prenatal Phthalate Exposure and Neurodevelopmental Outcomes in the MARBLES Cohort

Prenatal exposure to phthalates, a family of endocrine-disrupting plasticizers, is associated with disruption of maternal metabolism and impaired neurodevelopment. We investigated associations between prenatal phthalate exposure and alterations of both the maternal third trimester serum metabolome and the placental metabolome at birth, and associations of these with child neurodevelopmental outcomes using data and samples from the Markers of Autism Risk in Babies Learning Early Signs (MARBLES) cohort. The third trimester serum (n = 106) and placental (n = 132) metabolomes were investigated using 1H nuclear magnetic resonance spectroscopy. Children were assessed clinically for autism spectrum disorder (ASD) and cognitive development. Although none of the urinary phthalate metabolite concentrations were associated with maternal serum metabolites after adjustment for covariates, mixture analysis using quantile g-computation revealed alterations in placental metabolites with increasing concentrations of phthalate metabolites that included reduced concentrations of 2-hydoxybutyrate, carnitine, O-acetylcarnitine, glucitol, and N-acetylneuraminate. Child neurodevelopmental outcome was not associated with the third trimester serum metabolome, but it was correlated with the placental metabolome in male children only. Maternal phthalate exposure during pregnancy is associated with differences in the placental metabolome at delivery, and the placental metabolome is associated with neurodevelopmental outcomes in males in a cohort with high familial ASD risk.

Association of urinary phthalate metabolites with renal function among 9989 US adults

PURPOSE

This study aimed to investigate the relationship between phthalate metabolites and renal function.

METHODS

We analyzed data from 9989 participants who took part in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Renal function was reflected by estimated glomerular filtration rate (eGFR), urinary albumin-to-creatinine ratio (UACR), and hypertension. We used generalized linear regression to estimate the correlation between covariate-adjusted creatinine-normalized phthalate metabolites and renal function. In addition, subgroup analysis was used to further compare the effect differences between various populations.

RESULTS

In the adjusted model, we found differential associations between phthalates and plasticizers metabolites and renal function. We found that Mono-benzyl phthalate, Mono-(3-carboxypropyl) phthalate, and Mono-(2-ethyl-5-oxohexyl) phthalate were positively associated with lower eGFR with odds ratios (95% confidence intervals) of 1.38 (1.14, 1.67), 1.30 (1.09, 1.57), and 1.27 (1.04, 1.53). While Mono-ethyl phthalate, Mono-(2-ethyl)-hexyl phthalate, Mono-isononyl phthalate and Mono-isobutyl phthalate were negatively associated with lower eGFR with OR values of 0.79 (0.69, 0.90), 0.64 (0.52, 0.78), 0.65 (0.51, 0.82) and 0.80 (0.63, 1.00), respectively. In addition, we found that Mono(carboxyoctyl) phthalate and Mono-isobutyl phthalate were negatively associated with hypertension with ORs of 0.86 (0.78, 0.96) and 0.84 (0.72, 0.98). But phthalates and plasticizers metabolites were not associated with UACR.

CONCLUSION

This study found differences in the effects of phthalates and plasticizers metabolites on kidney function, which may raise concerns about possible changes in kidney function resulting from exposure to current levels of plasticizers.

Lycopene alleviates di(2-ethylhexyl) phthalate-induced splenic injury by activating P62-Keap1-NRF2 signaling

Di(2-ethylhexyl) phthalate (DEHP) is an omnipresent environmental pollutant. It has been determined that DEHP is involved in multiple health disorders. Lycopene (Lyc) is a natural carotenoid pigment, with anti-inflammatory and antioxidant properties. However, it is not clear whether Lyc can protect the spleen from DEHP-induced oxidative damage. A total of 140 mice were randomly divided into seven groups (n = 20) and continuously gavaged with corn oil, distilled water, DEHP (500 or 1000 mg/kg BW/day) and/or Lyc (5 mg/kg BW/day) for 28 days. Histopathological and ultrastructural results showed a DEHP-induced inflammatory response and mitochondrial injuries. Moreover, DEHP exposure induced redox imbalance, which resulted in the up-regulation of ROS activity and MDA content, and the down-regulation of T-AOC, T-SOD and CAT in the DEHP groups. Simultaneously, our results also demonstrated that DEHP-induced kelch-like ECH-associated protein 1 (Keap1) expression was downregulated, and the expression levels of P62, nuclear factor erythroid 2-related factor (NRF2) and their downstream target genes were up-regulated. However, the supplementary Lyc reverted these changes to normal levels. Together, Lyc prevented DEHP-induced splenic injuries by regulating the P62-Keap1-NRF2 signaling pathway. Hence, the protective effects of Lyc might be a therapeutic strategy to ameliorate DEHP-induced splenic damage.

Di-(2-ethylhexyl) phthalate exacerbated the toxicity of polystyrene nanoplastics through histological damage and intestinal microbiota dysbiosis in freshwater Micropterus salmoides

Organic pollutants such as di-(2-ethylhexyl) phthalate (DEHP) interact with nanoplastics (NPs) and change their bioavailability and toxicity to aquatic organisms. This study aims to assess the ecotoxicological impacts of NPs in the presence and absence of DEHP on juvenile largemouth bass (LMB) Micropterus salmoides. Therefore, LMB was fed with diets containing various concentrations (0, 2, 10, and 40 mg/g) of polystyrene nanoplastics (PSNPs) by the weight of diets. After a 21-day of PSNPs dietary exposure, LMB was treated with DEHP at 450 μg/L through waterborne exposure for three days. Our results showed that PSNPs were accumulated in the intestinal tissues, which significantly decreased the feeding and growth rates in LMB. The histopathological analysis showed the intestine and liver of LMB were subjected to various degrees of structural damage caused by PSNPs, and DEHP-PSNP co-exposure enhanced those histopathological damages in both tissues. Additionally, the co-exposure induced oxidative stress in terms of increased activities of glutathione S-transferase, catalase, and superoxide dismutase enzymes in the liver, intestine, spleen, and serum. Furthermore, the co-exposure significantly changed the intestinal microbial composition, i.e., the decrease in the abundance of probiotics (Bacteroidetes and Proteobacteria) and the increase in pathogenic bacteria (Firmicutes) posed a great threat to fish metabolism and health. Therefore, this study highlights that the presence of DEHP enhances the toxicity of NPs on LMB in freshwater and suggests the regulated use of plastic and its additives for improving the health status of aquaculture fish for food safety in humans.

Effects of Lycium barbarum glycopeptide on renal and testicular injury induced by di(2-ethylhexyl) phthalate

Di(2-ethylhexyl) phthalate (DEHP) is a common environmental pollutant with renal and reproductive toxicity. Lycium barbarum glycopeptide (LbGp) is the main active component of Lycium barbarum, which can protect the kidney and promote reproduction. Autophagy and apoptosis are the regulatory mechanisms of cell adaptation to external stress. This study investigated whether DEHP and LbGp affect kidney and testis by regulating autophagy and apoptosis. DEHP induced apoptosis in human embryonic kidney-293 (HEK-293) cells and human kidney-2 (HK-2) cells, as well as glomerular enlargement, enhanced renal autophagy and inflammation, decreased testicular germ cells, and enhanced testicular autophagy. LbGp reduced apoptosis in HEK-293 cells and HK-2 cells, reduced glomerular enlargement and renal inflammation, enhanced renal autophagy, increased testicular germ cells, and alleviated testicular autophagy. These results suggested that DEHP induced inflammation to cause kidney injury, mildly enhanced renal autophagy, and also induced excessive autophagy, leading to testicular injury. LbGp reduced inflammation and appropriately enhanced autophagy to alleviate renal injury and also reduced excessive autophagy to alleviate testicular injury. Silent information regulator 1 (SIRT1)/forkhead box O3a (FoxO3a)-mediated autophagy and p38 mitogen-activated protein kinase (p38 MAPK)-mediated inflammation played important roles.

Apigenin ameliorates di(2-ethylhexyl) phthalate-induced ferroptosis: The activation of glutathione peroxidase 4 and suppression of iron intake

Di(2-ethylhexyl) phthalate (DEHP) is a widely artificial persistent organic pollutant, the contamination of which infiltrates daily human life from many aspects, imperceptibly causing damage to multiple organs in the body, including the liver. Apigenin (APG) is widely distributed in vegetables and fruits and can relieve or prevent the injuries caused by exogenous chemicals through various pharmacological effects, such as antioxidant effects. To investigate the mechanism of DEHP-induced liver injury and the antagonistic effects of APG, we treated AML12 cells with 1 mM DEHP and/or APG. Ultrastructural morphology analysis indicated that DEHP induced typical ferroptosis-like damage. In addition, we found that DEHP exposure induced ferroptosis by enhancing reactive oxygen species (ROS) levels, disrupting iron homeostasis and lipid peroxidation, and regulating the expression of ferroptosis-related genes. Notably, supplementation with APG significantly inhibited these abnormal changes, and molecular docking further showed evidence of the activating effects of APG ligand on glutathione peroxidase 4 (GPX4). These results demonstrated that the protective effects of APG on DEHP-induced ferroptosis were achieved by activating GPX4 and suppressing intracellular iron accumulation. This information not only adds to DEHP toxicological data but also provides a basis for the practical application of APG.

Dysregulated Nrf2 signaling in response to di(2-ethylhexyl) phthalate in neutrophils of children with autism

Autism spectrum disorder (ASD) is characterized by constellation of impaired behaviors that include deficits in social interaction/communication and the presence of restricted/repetitive behavioral patterns. Both genetic component and environmental factors are thought to play a key role in the initiation and progression of ASD. Several environmental factors such as heavy metals and plasticizers are known to affect the progression of ASD. One of the most common pollutants in the environment today is di-2-ethylhexyl phthalate (DEHP). DEHP is utilized as a plasticizer in several household and office materials which range from medical devices to plastic toys. Children usually get exposed to DEHP at an early age through use of plastic toys and other plastic materials. Nuclear factor erythroid 2 (NFE2)-relatedfactor-2 (Nrf2) is a master redox regulator as it controls transcription of several antioxidant genes. DEHP has been reported to cause dysregulation in Nrf2 signaling in vitro/in vivo and ASD subjects also exhibit oxidant-antioxidant imbalance.Therefore, this study attempted to delineate the effect of DEHP on Nrf2 signaling in neutrophils of ASD and typically developing healthy children (TDC) in vitro. Our data display that neutrophils of ASD subjects have dysregulated Nrf2 and hemeoxygenase-1 (HO-1) expression as compared to TDC subjects. DEHP treatment leads to elevation of oxidant stress in neutrophils of both ASD and TDC subjects, however TDC neutrophils have better antioxidant response to mitigate oxidative stress. This is depicted by enhancement of Nrf2/HO-1 signaling in TDC neutrophils in response to DEHP whereas ASD neutrophils fail to do so. These results suggest that plasticizer, DEHP may cause further dysregulation in Nrf2 signaling which may promote progression of ASD.

Longitudinal changes in oxidative stress and early renal injury in children exposed to DEHP and melamine in the 2011 Taiwan food scandal

In 2011, phthalates, mainly di-(2-ethylhexyl) phthalate (DEHP), were found to have been added to a variety of foods in Taiwan, increasing the risk of microalbuminuria in children. Exposure to melamine perhaps modifies that risk. This prospective cohort study investigates whether renal injury resulting from exposure to DEHP-tainted foods from the 2011 Taiwan Food Scandal is reversed over time. The temporal and interactive effects of past daily DEHP intake, current daily DEHP intake, and urinary melamine levels on oxidative stress and renal injury were also examined. Two hundred possibly DEHP-affected children (aged < 18 years) were enrolled in the first survey wave (August 2012-January 2013), with 170 and 159 children in the second (July 2014-February 2015) and third waves (May 2016-October 2016), respectively. The first wave comprised questionnaires that were used to collect information about possible past daily DEHP intake from DEHP-tainted foods. One-spot first morning urine samples were collected to measure melamine levels, phthalate metabolites, and markers indicating oxidative stress (malondialdehyde and 8-oxo-2'-deoxyguanosine), and renal injury (albumin/creatinine ratio (ACR) and N-acetyl-beta-D-glucosaminidase) in all three waves. Generalized estimating equation (GEE) modeling revealed that both past daily DEHP intake and time might affect urinary ACR. However, most interactions were negative and significant correlation was observed only during the second wave (P for interaction = 0.014) in the group with the highest past daily DEHP intake (>50 μg/kg/day). Urinary melamine levels were found to correlate significantly with both urinary ACR and oxidative stress markers. The highest impact associated with exposure to DEHP-tainted foods in increasing urinary ACR of children was observed during the first wave, and the effect may partially diminish over time. These results suggest that continuous monitoring of renal health and other long-term health consequences is required in individuals who were affected by the scandal in 2011.

Lycopene prevents DEHP-induced hepatic oxidative stress damage by crosstalk between AHR-Nrf2 pathway

Di (2-ethylhexyl) phthalate (DEHP) is a widespread plasticizer that persists in the environment and can significantly contribute to serious health hazards of liver especially oxidative stress injury. Lycopene (LYC) as a carotenoid has recently gained widespread attention because of antioxidant activity. However, the potential mechanism of DEHP-induced hepatotoxicity and antagonism effect of LYC on it are still unclear. To explore the underlying mechanisms of this hypothesis, the mice were given by gavage with LYC (5 mg/kg) and DEHP (500 or 1000 mg/kg). The data suggested that DEHP caused liver enlargement, reduction of antioxidant activity markers, increase of oxidative stress indicators and disorder of cytochrome P450 enzymes system (CYP450s) homeostasis. DEHP-induced reactive oxygen species (ROS) activated the NF-E2-relatedfactor2 (Nrf2) and nuclear xenobiotic receptors (NXRs) system including Aryl hydrocarbon receptor (AHR), Pregnane X receptor (PXR) and Constitutive androstane receptor (CAR). Interestingly, these disorders and injuries were prevented after LYC treatment. Taken together, DEHP administration resulted in hepatotoxicity including oxidative stress injury and disordered CYP450 system, but these alterations might be ameliorated by LYC via crosstalk between AHR-Nrf2 pathway.

Redox modulation of vitagenes via plant polyphenols and vitamin D: Novel insights for chemoprevention and therapeutic interventions based on organoid technology

Polyphenols are chemopreventive through the induction of nuclear factor erythroid 2 related factor 2 (Nrf2)-mediated proteins and anti-inflammatory pathways. These pathways, encoding cytoprotective vitagenes, include heat shock proteins, such as heat shock protein 70 (Hsp70) and heme oxygenase-1 (HO-1), as well as glutathione redox system to protect against cancer initiation and progression. Phytochemicals exhibit biphasic dose responses on cancer cells, activating at low dose, signaling pathways resulting in upregulation of vitagenes, as in the case of the Nrf2 pathway upregulated by hydroxytyrosol (HT) or curcumin and NAD/NADH-sirtuin-1 activated by resveratrol. Here, the importance of vitagenes in redox stress response and autophagy mechanisms, as well as the potential use of dietary antioxidants in the prevention and treatment of multiple types of cancer are discussed. We also discuss the possible relationship between SARS-CoV-2, inflammation and cancer, exploiting innovative therapeutic approaches with HT-rich aqueous olive pulp extract (Hidrox®), a natural polyphenolic formulation, as well as the rationale of Vitamin D supplementation. Finally, we describe innovative approaches with organoids technology to study human carcinogenesis in preclinical models from basic cancer research to clinical practice, suggesting patient-derived organoids as an innovative tool to test drug toxicity and drive personalized therapy.

Mechanistic insight into toxicity of phthalates, the involved receptors, and the role of Nrf2, NF-κB, and PI3K/AKT signaling pathways

The wide use of phthalates, as phthalates are used in the manufacturing of not only plastics but also many others goods, has become a main concern in the current century because of their potency to induce deleterious effects on organism health. The toxic effects of phthalates such as reproductive toxicity, cardiotoxicity, hepatotoxicity, nephrotoxicity, teratogenicity, and tumor development have been widely indicated by previous experimental studies. Some of the important mechanisms of toxicity by phthalates are the induction and promotion of inflammation, oxidative stress, and apoptosis. Awareness of the involved molecular pathways of these mechanisms will permit the detection of exact molecular targets of phthalates to protect or treat their toxicity. Up to now, various transcription factors and signaling pathways have been associated with phthalate-induced toxicity which by influencing on nuclear surface and the expression of different genes can alter cell hemostasis. In different studies, the role of nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear factor-κB (NF-κB), and phosphatidylinositol-3-kinase (PI3K)/AKT signaling pathways in processes of oxidative stress, inflammation, apoptosis, and cancer has been shown following exposure to phthalates. In the present review, we aim to survey experimental studies (in vitro and in vivo) in order to show firstly the most involved receptors and also the importance and the role of the mentioned signaling pathways in phthalate-induced toxicity, and with considering this point, the future studies can focus on these molecular targets as a strategic method to reduce environmental chemicals-induced toxicity especially phthalates toxic effects.

Hydrogen Sulfide and Carnosine: Modulation of Oxidative Stress and Inflammation in Kidney and Brain Axis

Emerging evidence indicates that the dysregulation of cellular redox homeostasis and chronic inflammatory processes are implicated in the pathogenesis of kidney and brain disorders. In this light, endogenous dipeptide carnosine (β-alanyl-L-histidine) and hydrogen sulfide (H₂S) exert cytoprotective actions through the modulation of redox-dependent resilience pathways during oxidative stress and inflammation. Several recent studies have elucidated a functional crosstalk occurring between kidney and the brain. The pathophysiological link of this crosstalk is represented by oxidative stress and inflammatory processes which contribute to the high prevalence of neuropsychiatric disorders, cognitive impairment, and dementia during the natural history of chronic kidney disease. Herein, we provide an overview of the main pathophysiological mechanisms related to high levels of pro-inflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and neurotoxins, which play a critical role in the kidney–brain crosstalk. The present paper also explores the respective role of H₂S and carnosine in the modulation of oxidative stress and inflammation in the kidney–brain axis. It suggests that these activities are likely mediated, at least in part, via hormetic processes, involving Nrf2 (Nuclear factor-like 2), Hsp 70 (heat shock protein 70), SIRT-1 (Sirtuin-1), Trx (Thioredoxin), and the glutathione system. Metabolic interactions at the kidney and brain axis level operate in controlling and reducing oxidant-induced inflammatory damage and therefore, can be a promising potential therapeutic target to reduce the severity of renal and brain injuries in humans.