Polystyrene micro- and nano-particle coexposure injures fetal thalamus by inducing ROS-mediated cell apoptosis

Monitoring nanoplastic aging in situ by moth-eye mimic plasmonic substrates

Micro-nano plastics aging is crucial as it determines the environmental fate of each plastic particle, yet few studies involved in situ aging of nanoplastics. Herein, we utilized nanosphere lithography combined with goldnanorod assembly to prepare a moth-eye mimic plasmonic substrate featuring excellent SERS performance. The substrate was applied to in situ characterize the degradation process of PS nanoplastics during UV aging. Raman spectra evidence that the substrate is sensitive to superficial chemical changes of PS nanoplastics at initial stage during 24 h of continuous UV aging. The disruption of the benzene ring skeleton, the oxidation of the side chains of PS nanoplastics during UV aging, and the presence of oxidized methylene straight chains were identified. Practical applications in environmental sample revealed the chemical changes of PP, PS, and PE, which confirm the great potential of this SERS substrate for aging studies of nanoplastics.

Unveiling the effects of micro and nano plastics in embryonic development

The improper disposal and degradation of plastics causes the formation and spread of micro and nano-sized plastic particles in the ecosystem. The widespread presence of these micro and nanoplastics leads to their accumulation in the biotic and abiotic components of the environment, thereby affecting the cellular and metabolic functions of organisms. Despite being classified as xenobiotic agents, information about their sources and exposure related to reproductive health is limited. Micro and nano plastic exposure during early developmental stages can cause abnormal embryonic development. It can trigger neurotoxicity and inflammatory responses as well in the developing embryo. In embryonic development, a comprehensive study of their role in pluripotency, gastrulation, and multi-differentiation potential is scarce. Due to ethical concerns associated with the direct use of human embryos, pluripotent cells and its 3D in vitro models (with cell lines) are an alternative source for effective research. Thus, the 3D Embryoid body (EB) model provides a platform for conducting embryotoxicity and multi-differentiation potential research. Pluripotent stem cells such as embryonic and induced pluripotent stem cells derived embryoid bodies (EBs) serve as a robust 3D in vitro model that mimics characteristics similar to that of human embryos. Thus, the 3D EB model provides a platform for conducting embryotoxicity and multi-differentiation potential research. Accordingly, this review discusses the significance of 3D in vitro models in conducting effective embryotoxicity research. Further, we also evaluated the possible sources/routes of microplastic generation and analyzed their surface chemistry and cytotoxic effects reported till date.

Trehalose Acts as a Mediator: Imbalance in Brain Proteostasis Induced by Polystyrene Nanoplastics via Gut Microbiota Dysbiosis during Early Life

As an emerging contaminant, nanoplastics have evolved into a global ecological issue. Studies have shown that nanoplastics induce neurotoxicity across species, however, the causal mechanism remains unknown. This study aimed to explore the mechanism underlying the neurotoxicity caused by polystyrene nanoplastics (PS-NPs) via microbiota-gut-brain axis in immature mice, which serve as a model of infants and young children who are at higher exposure risk to NPs. The results indicated that while only a minority of PS-NPs reached the brain after exposure, they still had significant neurotoxic effects, as reflected by abnormalities in behavior, biochemical marker levels and histopathology. Proteomics and quantification analyses revealed that a proteostasis imbalance mediated by lysosomal and proteasome dysfunction in the brain is the key reason for the induced neurotoxicity. Further, we confirmed the indirect role of gut microbiota in the neurotoxicity induced by PS-NPs through 16S rDNA analyses and fecal microbiota transplantation. Crucial bacterial species such as Eubacterium coprostanoligenes potentially act as indicators for gut dysbiosis after PS-NPs exposure. Notably, we first estimated the indirect effect of gut microbiota on neurotoxicity attributed to PS-NPs in immature mice as 39.20% by high-dimensional mediation analysis. Trehalose was identified as a mediator connecting the gut microbiota and the brain, and the crucial role of trehalose supplementation was highlighted in remodeling the brain proteostasis to alleviate the neurotoxicity in immature mice. These findings are expected to contribute to a deeper understanding of the risk assessment and health protection of the nervous system from exposure to PS-NPs early in life.

Gestational exposure to micro- and nanoplastics leads to poor pregnancy outcomes by impairing placental trophoblast syncytialization

The omnipresent micro- and nanoplastics (MNPs), emerging environmental contaminants, have caused a widespread concern because of their potential threats to public health. Increasing evidence has indicated that MNPs were deeply involved in poor pregnancy outcomes, but the detailed mechanism remains obscure. In this research, we firstly identified that maternal exposure to MNPs during gestation increased both the number and rate of embryo resorption, while reducing embryonic weight, placental diameter and placental weight. This was accompanied by disrupted progesterone and estradiol synthesis in MNPs-treated mouse placentas. In addition, our data suggested that MNPs exposure disturbed placental development, as evidenced by the reduction of the total area of placenta, area of spongiotrophoblast layer and area of labyrinth layer. Subsequently, in vivo and in vitro experiments further indicated that MNPs compromised syncytialization process and decreased the expression of syncytialization markers in mouse placentas and human placental trophoblasts. Further investigation indicated that PERK/eIF2α/ATF4 signaling was activated in MNPs-treated mouse placentas and human placental trophoblasts. More importantly,inhibition of PERK partially restored syncytialization insufficiency caused by MNPs administration. On the whole, our results suggested that gestational exposure to MNPs disturbed placental trophoblasts syncytialization possibly through activating PERK/eIF2α/ATF4 pathway, resulting in aberrant placentation and poor pregnancy outcomes.

Mechanistic insight on nanomaterial-induced reactive oxygen species formation

Reactive oxygen species (ROS) are closely related to cell death, proliferation and inflammation. However, excessive ROS levels may exceed the cellular oxidative capacity and cause irreversible damage. Organisms are often inadvertently exposed to nanomaterials (NMs). Therefore, elucidating the specific routes of ROS generation induced by NMs is crucial for comprehending the toxicity mechanisms of NMs and regulating their potential applications. This paper provides a comprehensive review of the toxicity mechanisms and applications of NMs from three perspectives: (1) Organelle perspective. Investigating the impact of NM-mediated ROS on mitochondria, unraveling mechanisms at the organelle level. (2) NMs' perspective. Exploring the broad applications and biosafety considerations of Nanozymes, a unique class of NMs. (3) Cellular system. Examining the toxic effects and mechanisms of NMs in cells at a holistic cellular level. Expanding on these perspectives, the paper scrutinizes the regulation of Fenton reactions by NMs in organisms. Furthermore, it introduces diseases resulting from NM-mediated ROS at the organism level. This comprehensive review aims to provide valuable insights for studying NM-mediated mechanisms at both cellular and organism levels, offering considerations for the safe design of nanomaterials.

Gender-specific effects of prenatal polystyrene nanoparticle exposure on offspring lung development

Nanoplastics are widely present in the environment. Exposure to environmental pollutants during pregnancy can have adverse effects on fetal development and health. Establishing a link between nanoplastics and Bronchopulmonary Dysplasia (BPD) requires further investigation. In this study, we examined the impact of prenatal exposure to 80 nm polystyrene nanoparticles (PS-NPs) on offspring lung development, taking into account potential gender-specific effects. Pregnant female mice were exposed to PS-NPs through oropharyngeal aspiration, and critical data on lung development were collected at postnatal days 1, 7, and 21. We found that exposure to PS-NPs reduced birth weight in female offspring and significantly increased lung weight in both male and female offspring by PND 21. Maternal exposure led to a reduction in alveolar numbers across offspring, with distinct underlying mechanisms observed between sexes. In female offspring, the reduction in alveolar numbers was linked to disrupted surfactant protein expression, significant inflammation, and increased apoptosis and fibrosis. In male offspring, impaired angiogenesis was the primary factor contributing to the increased risk of BPD. The impact on alveolar development was substantial in both genders. This study underscores the gender-specific impacts of prenatal nanoplastic exposure on lung development and offers new evidence and direction for future research on the cross-generational respiratory toxicity of PS-NPs.

Co-exposure to ozone and polystyrene nanoplastic exacerbates cognitive impairment and anxiety-like behavior by regulating neuronal pyroptosis in mice

Ozone (O3) and nanoplastics (NPs) are pervasive environmental pollutants that frequently co-occur in our heavily industrialized era. While it has been documented that exposure to O3 or NPs individually has neurotoxic effects, studies investigating their combined impact and the hazardous mechanisms resulting from co-exposure are limited. In this study, we established a mouse model co-exposure to polystyrene nanoparticles (PS-NPs) and O3, focusing on the prefrontal cortex (PFC), a brain region crucial for cognition and emotion. We examined the effects of O3 and PS-NPs on behavioral changes related to learning, memory, and anxiety, employing transcriptome sequencing alongside molecular and histopathological methods. Our findings indicate that combined exposure to O3 and PS-NPs disrupts the integrity of the blood-brain barrier, reducing Claudin 5 expression and leading to increased accumulation of PS-NPs in the PFC. Transcriptome sequencing demonstrated the involvement of the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway and oxidative stress in the pathological changes observed in the PFC. Through immunohistochemical and immunofluorescence analysis, we observed enhanced microglial activation, which correlates with increased production of inflammatory factors. Additionally, western blot and immunofluorescence co-labeling analyses revealed elevated expression levels of GSDMD-N, caspase-1, IL-1β, and IL-18 proteins, which are associated with neuronal pyroptosis. Finally, immunofluorescence co-labeling confirmed that the activation of the p38 MAPK pathway in neurons is involved in co-exposure-induced pyroptosis. Meanwhile, N-Acetylcysteine (NAC), a common antioxidant, can alleviate neuroinflammation and neuronal pyroptosis in the PFC, and it rescued the cognitive deficits and anxiety-like behaviors observed in the co-exposed mice. Our study illustrates that co-exposure to O3 and NPs can aggravate damage to the blood-brain barrier and elevate oxidative stress levels in the PFC, thereby increasing the occurrence of neuroinflammation and may mediate neuronal pyroptosis through activation of the p38 MAPK pathway, ultimately contributing to neurobehavioral toxicity.

Subchronic Exposure to Polystyrene Nanoplastics Disrupts Placental Development and Calcium Homeostasis: Insights from In Vivo and In Vitro Models

Nanoplastics have recently emerged as persistent pollutants of global concern that pose substantial risks to human health. However, the long-term adverse effects of nanoplastics on the female reproductive system remain unclear. Polystyrene nanoplastics (PS-NPs; 50 nm diameter) were selected as representative nanosized plastic particles to investigate the potential effects of subchronic prenatal and gestational exposure via drinking water on placental development in ICR (CD-1) mice. Maternal exposure to 10 mg/L PS-NPs induced an increase in fetal resorption rate and significantly increased fetal weight. Further observation of the placental morphology showed that PS-NPs exposure led to an aberrant placental structure and damaged the trophoblast cells. At the cellular level, PS-NPs exposure promoted the proliferation, migration, and invasion of HTR-8/SVneo cells. Mechanistically, transcriptomic and proteomic analyses revealed that PS-NPs triggered placental calcium disturbances and upregulated the Stam2 expression in mice. STAM2 induced by PS-NPs mediates the disruption of trophoblastic calcium homeostasis and regulates cell functions by disturbing the lysosomal degradation of the calcium channel protein IP3R3 and promoting intracellular calcium inflow by increasing the level of TRPV6 in HTR-8/SVneo cells. Therefore, our results indicated that trophoblastic calcium dyshomeostasis is the main mechanism by which subchronic PS-NPs exposure induces abnormal placental development. These findings reveal a link between subchronic PS-NPs exposure and placental damage and elucidate the underlying molecular mechanism, providing evidence for environmental triggers of adverse pregnancy and highlighting the risk of plastic products to pregnant women.

Perinatal exposure to polystyrene nanoplastics alters socioemotional behaviors via the microbiota-gut-brain axis in adult offspring mice

Polystyrene nanoplastics (PS-NPs), ubiquitous environmental contaminants, have been detected in various tissues of humans and animals, raising significant concerns regarding their potential health hazards. The long-term consequences of PS-NPs exposure during early developmental stages remain inadequately characterized. In this study, we established a murine model to investigate the chronic oral administration of PS-NPs via drinking water during the perinatal period, with a focus on elucidating the impact of PS-NPs ingestion on the social behaviors of adult offspring and the underlying mechanisms, particularly those involving the gut-brain axis. Our findings revealed that perinatal PS-NPs exposure elicited depression-like behaviors, diminished social dominance, and reduced social interactions in adult offspring. Additionally, we observed a decrease in dendritic spine density within hippocampal neurons, along with ultrastructural damage to hippocampal neurons and synapses in the adult offspring. PS-NPs exposure also led to a reduction in the richness and evenness of gut microbiota species composition in both male and female mice, with gut dysbiosis being particularly pronounced in adult males. Furthermore, alterations in metabolite abundance and metabolic pathways were detected in the hippocampus of both male and female adult offspring. Notably, a significant correlation was identified between the relative abundance of intestinal microorganisms and hippocampal metabolites. These results offer new insights into the association between early-life PS-NPs exposure and adult social behaviors, mediated through the microbiota-gut-brain axis.

In vivo and In vitro assessment of the retinal toxicity of polystyrene nanoplastics

Plastic pollution has emerged as a critical global environmental challenge, yet the effects of the ingested plastic particles on ocular health remain largely unexplored. In this study, we investigated the impact of orally ingested polystyrene nanoplastics (PS-NPs) on the mouse retina. The in vivo experimental results showed that PS-NPs could penetrate the mouse retina within 2 h after gavage. Their levels increased at 4 h and remained detectable up to 24 h post-gavage. Prolonged exposure (28 days) to PS-NPs might disrupt the tight junctions of the inner blood-retinal barrier (iBRB). Moreover, PS-NPs induced oxidative stress in the retina by downregulating the expression of Nrf2 and HO-1, and potentially promoted apoptosis via the upregulation of Cleaved caspase 3. Additionally, we used human retinal microvascular endothelial cells (HRMECs) to model the iBRB and employed a human retinal pigment epithelial cell line (ARPE-19) to assess the potential toxicity of PS-NPs on the human retina. Our results indicated that PS-NPs penetrated and disrupted the simulated iBRB, inducing oxidative stress and promoting apoptosis in ARPE-19 cells. This study provides critical insights into the potential risks of ingested PS-NPs to retinal health and offers novel perspectives on the broader implications of plastic pollution for humans.

Gestational exposure to polystyrene microplastics incurred placental damage in mice: Insights into metabolic and gene expression disorders

As an emerging environmental pollutant, microplastics have attracted increasing attention to their potential health hazards. However, the current understanding about the toxicity and health implications, especially about developmental toxicity with exposure to microplastics is quite limited. In the current study, we aimed to scrutinize the deleterious effects of polystyrene microplastics (PSMPs) with different sizes (0.1 and 5 μm) on the placenta that plays crucial role in fetal development, following oral exposure during gestational stages. The results showed that two sizes of PSMPs could distribute in mouse placental tissues, and nanosized PSMPs (0.1 μm) exhibited greater capability to penetrate the placenta and deposit in the liver and brain of fetuses than microsized PSMPs (5 μm). Importantly, only 0.1 μm PSMPs induced a decrease in the junctional area, a reduction in the labyrinthine vascularization and an increase in cell apoptosis in the placenta, accompanied by fetal developmental impairments. The results of metabolome and transcriptome uncovered that 0.1 μm PSMP exposure caused changes in metabolic and gene profiles of placental tissues, across multiple pathways such as vascular supply, nutrient absorption and transportation and amino acid metabolism. Overall, our results confirmed that maternal PSMP exposure led to placental damages associated with metabolic and gene expression disorders. This study would provide new insights into the developmental impacts of microplastic consumption during gestation.

Developmental Toxicity of Micro(Nano)Plastics (MNPs) Exposure in Mammals: A Mini-Review

Micro(nano)plastics (MNPs) pose a significant threat to both ecological environments and human health. This review systematically examines the developmental toxicity of MNPs in mammals, with a particular focus on the impact of maternal and paternal exposure on offspring. Evidence indicates that MNPs can cross placental barriers, inducing abnormal development of embryos, fetuses, and placentas. This disruption leads to a range of adverse outcomes, including neurodevelopmental abnormalities, behavioral disorders, reproductive system damage, etc., in offspring. Through a comprehensive analysis of the existing literature, this review aims to provide a foundation for future research on the developmental toxicity of MNPs and highlight the urgent need for action to mitigate the detrimental effects of MNPs on human health and ecosystem integrity.

Microplastics induce human kidney development retardation through ATP-mediated glucose metabolism rewiring

Recent research has revealed an accumulation of microplastics (MPs) in the environment and human tissues, giving rise to concerns about their potential toxicity. The kidney is a vital organ responsible for various physiological functions. Early kidney development is crucial for ensuring proper structure and function. Nevertheless, the impact of MPs on renal development is unclear. In the current study, we examined the effect of MPs on nephrogenesis using human kidney organoids. The environmentally relevant concentrations of MPs were applied. Following MP exposure, the kidney organoids exhibited reduced size and abnormal tubular structures. MPs caused an increased level of mitochondrial reactive oxygen species and DNA damage. Transcriptomic and central carbon metabolism analysis data revealed significant alterations in metabolic pathways after MP exposure, with a decrease in glycolysis and an increase in tricarboxylic acid cycle activity. Moreover, glycolysis inhibition was identified as a contributing factor to the reduced size and abnormal tubular structure of the kidney organoids. These results emphasize the negative effects of MPs on renal development through metabolic reprogramming. Our study provides a novel perspective of MP-induced nephron toxicity mechanisms. The affected pathways and metabolites identified here may act as early biomarkers and therapeutic targets for PS-MP-induced renal toxicity.

Intranasal Zinc Oxide Nanoparticles Induce Neuronal PANoptosis via Microglial Pathway

Recent data have revealed an increased risk of respiratory exposure during the manufacturing process and application of nanomaterials, resulting in an increased incidence of neurodegenerative diseases in the general population. Zinc oxide nanoparticles (ZNPs) are among the most used nanomaterials in biomedical and manufactured consumer products. In this study, neurological dysfunction after intranasal administration of ZNPs is observed, in which the ZNPs enter the brain via the nose-to-brain pathway and accumulate in microglia but not in astrocytes or neurons. By using a coculture system of microglia and neurons, the ZNPs are found that induce microglia-derived oxidative stress injury and lead to neuronal cell PANoptosis. In this context, ZNPs induced the generation of reactive oxygen species (ROS) originating from microglial NADPH oxidase 2 (NOX2), which further induced neuronal membrane lipid peroxidation and increased Ca2+ influx and mitochondrial DNA release. The leaked mitochondrial DNA subsequently initiates PANoptosis of neurons. Importantly, inhibition of microglial NOX2 activation can significantly alleviate brain oxidative injury and rescue neuronal PANoptosis. This study can advance the understanding of the mode of neuronal cell death while underscoring the importance of the interconnections among glial cells and neurons, which is beneficial for informing effective interventions for respiratory exposure to nanoparticles.

Investigation of potential toxic effects of nano- and microplastics on human endometrial stromal cells

Nanoplastics (NPs) and microplastics (MPs) have become a global concern in recent years. Most current research on the impact of plastics on obstetrics has focused on their accumulation in specific tissues in animal models and the disease-causing potential of MPs. However, there is a relative lack of research on the cellular changes caused by the accumulation of MPs. In this study, we aimed to establish a proper in vitro exposure protocol for polystyrene (PS)-NPs and MPs and to investigate possible cytotoxic effects of PS-NPs and MPs on human endometrial stromal cells (ESCs) using different plastic sizes and concentrations. The results showed that smaller plastics, specifically 100 nm PS-NPs and 1 μm PS-MPs, had a higher cellular uptake propensity than larger particles, such as 5 μm PS-MPs, with significant morphological changes and cell death observed at concentrations above 100 μg/mL a 24-h period. In addition, confocal microscopy and real-time imaging confirmed the accumulation of these particles in the nucleus and cytoplasm, with internalization rates correlating with particle size. Also, 100 nm PS-NPs reduced cell proliferation and induced apoptosis. In conclusion, this study demonstrates that exposure to 100 nm PS-NPs and 1 μm PS-MPs leads to dynamic accumulation in ESCs, resulting in cell death or decreased proliferation at specific concentrations, which highlights the potential cellular toxicity of NPs or MPs.

Exposure to polystyrene nanoplastics causes anxiety and depressive-like behavior and down-regulates EAAT2 expression in mice

Microplastics exposure can induce brain dysfunction like cognitive impairment, Parkinson's disease, and autism spectrum disorders. In this study, we aimed to investigate the effects of Polystyrene nanoplastics (NPS) on anxiety and depression in mice. First, Polystyrene nanoplastics (NPS) (10 mg/kg) were administered orally daily for two months starting at PND 21. Subsequently, behavioral tests about anxiety and depression were conducted, including the open field test, the elevated plus maze, the forced swimming test, and the tail suspension test. The results showed that NPS induced anxiety and depression-like behaviors in mice. The mPFC played a pivotal role in the etiology of anxiety and depression, in which nanoplastics led to impaired synaptic transmission and reduced neuronal activity in vivo in mPFC. Furthermore, the astrocyte marker GFAP was abnormally increased as observed in mPFC. The abnormal activation of astrocytes results in impaired glutamate recycling through decreasing the expression of the glutamate transporter protein EAAT2 after NPS exposure. In order to ascertain the function of EAAT2, the EAAT2 activator (LDN-212320) was employed to stimulate the expression of EAAT2. Following the activation of EAAT2, synaptic transmission, and anxiety and depressive behavior were rescued in the mice. Polystyrene nanoplastics induce anxiety and depressive-like behavior in mice possibly inhibiting astrocyte EAAT2 expression. Specific activation EAAT2 of astrocytes rescue anxiety and depressive behavior in nanoplastics exposed mice.

HIF-1α/HO-1-Mediated Ferroptosis Participates in Polystyrene Nanoplastics-Induced Intergenerational Cardiotoxicity

To explore the intergenerational cardiotoxicity of nanoplastics, maternal mice were exposed to 60 nm polystyrene nanoplastics (PS-NP) during pregnancy and lactation. The results showed that PS-NP can enter the hearts of offspring and induce myocardial fiber arrangement disorder, acidophilic degeneration of cardiomyocytes, and elevated creatine kinase isoenzymes (CK-MB) and lactate dehydrogenase (LDH) levels after maternal exposure to PS-NP at 100 mg/kg during pregnancy and lactation. Mechanistically, KEGG analysis of RNA sequencing showed the participation of hypoxia-inducible factor-1 (HIF-1) and ferroptosis in PS-NP-induced cardiotoxicity. Key features of ferroptosis, including Fe2+ accumulation, mitochondrial injury, oxidative stress, GPX4 downregulation, and FTH1, ACSL4, and SLC7A11 upregulation, were detected. Furthermore, PS-NP treatment upregulated the expressions of HIF-1α and HO-1, and PS-NP-induced ferroptosis can be alleviated by inhibition of HIF-1α using si-HIF-1α. This study provided an insightful reference for the intergenerational cardiotoxicity assessment of PS-NP.

Teratological, neurochemical and histomorphic changes in the limbic areas of F1 mice progeny due to co-parental polystyrene nanoplastic exposure

In the present study, co-parental exposure to polystyrene nanoplastics (PS-NPs) elicits profound teratological impacts, including skeletal and visceral malformations, post-natal effects on neonatal growth and neurobehavioral development in F1 progeny. A comprehensive investigation was conducted on Swiss albino mice fetuses, neonates (PND 1-21) and adult mice offsprings (PND 60) following parental exposure during spermatogenesis and oogenesis period, as well as continued maternal exposure during gestation and weaning. The parental mice were administered PS-NPs via oral gavage at low dose (0.2 mg/kg/day) and high dose (1 mg/kg/day). Both male and female parental mice were exposed to PS-NPs for 60 days and 14 days, respectively before mating. After the mating, the pregnant female mice continued to receive PS-NPs treatment during the gestation, till the subsequent weaning period. Our findings revealed that PS-NPs led to significant reductions in growth, and heightened skeletal and visceral anomalies in developing fetuses. Exposure further impaired reflexes in neonatal mice such as grasping, surface righting and negative geotaxis. Moreover, the adult progeny also exhibited learning impairments. Neurodevelopmental assessment unveiled alterations in neurotransmitter levels, antioxidant enzyme activities, and structural changes in key limbic areas such as the cortex, hippocampus, and hypothalamus of adult mice offspring. These alterations included increased vacuolization, vascular dilation, and reduced pyramidal neurons in the hippocampus. Thus, this transgenerational study underscores the detrimental effects of PS-NPs on both prenatal and postnatal development, emphasizing teratological and enduring neurological consequences in the limbic regions of F1 progeny mice brains.

Impact of microplastics on female reproductive health: insights from animal and human experimental studies: a systematic review

OBJECTIVE

This systematic review aims to evaluate the impact of microplastics on female reproductive health by analyzing experimental studies.

METHOD

A comprehensive search was conducted in PubMed, Web of Science, and Scopus databases to identify experimental studies published between 2021 and 2023. Studies investigating the effects of microplastics on reproductive organs, hormone levels, fertility rates, and offspring development in female subjects were included. The quality of the studies was assessed using the Cochrane risk of bias tool.

RESULTS

A total of 15 studies met the inclusion criteria. The results indicate that exposure to microplastics significantly affects ovarian function, decreases fertility rates, and disrupts hormone levels in female subjects. Several studies also reported negative effects on embryo development and offsprings health. The quality of the studies varied, with some showing a high risk of bias.

CONCLUSION

The evidence from experimental studies suggests that microplastics have a detrimental effect on female reproductive health. However, the variation in study quality highlights the need for more rigorous research to confirm these results and better understand the underlying mechanisms.

Gestational exposure to carbon black nanoparticles triggered fetal growth restriction in mice: The mediation of inactivating autophagy-lysosomal degradation system in placental ferroptosis

Carbon black nanoparticles (CBNPs) are ubiquitous in our daily ambient environment, either resulting from tobacco combustion or constituting the core of PM2.5. Despite the potential risk of trafficking CBNPs to the fetus, the underlying toxicity of nano-sized carbon black particles in the placenta remains unambiguous. Pregnant C57BL/6 mice received intratracheal instillation of 30 nm or 120 nm CBNPs. CBNPs deposited in the lungs could infiltrate the red blood cells, further cross into the placenta, and cause fetal growth restriction. Mechanistically, we proposed a two-hit hypothesis in placenta response to CBNPs. The first hit was that CBNPs caused mitochondrial damage, reflected in the reduced mitochondrial matrix, the excessive mitochondrial fission, and the decreased mitochondrial membrane potential and mtDNA copy number. The second hit was that CBNPs disrupted the autophagy-lysosomal degradation system, impeding the removal of dysfunctional mitochondria and resulting in ferroptosis. Ferrestatin-1, a ferroptosis inhibitor, and rapamycin, an autophagy promotor, reversed ferroptosis and further confirm our suspicion. The findings suggested that CBNPs-triggered double-hit evoked placental ferroptosis, leading to fetal growth restriction. The study raised concerns about the potential placental toxicity of CBNPs and its impact on the fetal adverse outcome, which may propose potential targets for interventions in placental damage.

Intestinal Barrier Damage and Growth Retardation Caused by Exposure to Polystyrene Nanoplastics Through Lactation Milk in Developing Mice

Microplastics, defined as plastic fragments smaller than 5 mm, degrade from larger pollutants, with nanoscale microplastic particles presenting significant biological interactions. This study investigates the toxic effects of polystyrene nanoplastics (PS-NPs) on juvenile mice, which were exposed through lactation milk and drinking water at concentrations of 0.01 mg/mL, 0.1 mg/mL, and 1 mg/mL. The results show that PS-NP exposure during lactation and juvenile periods caused delayed weight gain and impaired organ development, particularly in the liver and kidneys, without causing functional abnormalities or toxic injuries. The primary toxicity of PS-NPs was observed in the intestinal tract, including shortened villi, disrupted tight junctions, inhibited epithelial cell proliferation, and oxidative stress responses. These findings highlight the importance of evaluating the developmental toxicity of nanoplastics at environmentally relevant doses.

S32, a Novel 3-Acetylaminocoumarin Compound, Exerts Neuroprotective Effects through the Inhibition of Neuroinflammation and Oxidative Stress In Vitro and In Vivo

Neuroinflammation and oxidative stress are key factors leading to neuronal injury. In this study, we investigated the role of S32, a novel 3-acetylaminocoumarin compound, in ameliorating neuronal injury induced by neuroinflammation and oxidative stress in vitro and in vivo. First, we found that S32 reduced the expression levels of p-P65 and p-P38, inhibited the nuclear translocation of P65, and lowered the levels of pro-inflammatory factors in LPS-induced BV2 cells, which indicated that S32 had an antineuroinflammatory effect. Second, BV2 cell culture medium was used as the conditioned medium to establish a model of oxidative damage in PC12 cells. It was found that S32 reduced the level of ROS and increased mitochondrial membrane potential of PC12 cells, which indicated that S32 can protect PC12 cells against conditioned medium-induced injury. Next, we found that S32 inhibited the decrease of cell viability of PC12 cells caused by H2O2, inhibited nuclear damage, decreased the level of ROS, increased MMP, activated the AKT and ERK pathways, increased Bcl-2 levels, and decreased Bax and Cleaved-Caspase3 expression levels, indicating that S32 ameliorated the damaging effects of H2O2-induced PC12 cells. Finally, we found that S32 exerted the antineuroinflammatory and apoptosis-inhibiting effects in LPS-induced mice. In conclusion, this study first demonstrated that S32, a novel 3-acetylaminocoumarin compound, can reduce neuroinflammation and neuroinflammation-induced neuronal injury, exerting an indirect protective effect on neurons, and also exert a direct protective effect on neurons by reducing oxidative stress.

Oxidative stress and its role in recurrent pregnancy loss: mechanisms and implications

Recurrent pregnancy loss (RPL) is the occurrence of two or more consecutive miscarriages before 20 weeks of gestation. Recent research has increasingly focused on the role of oxidative stress in RPL, providing insights into its underlying mechanisms and potential therapeutic targets. Oxidative stress arises from an imbalance between reactive oxygen species (ROS) production and antioxidant defenses, leading to cellular damage and inflammation. Oxidative stress has been implicated in disrupting placental blood flow, inducing apoptosis in fetal and placental cells, and exacerbating inflammatory responses, all of which can contribute to pregnancy loss. Elevated levels of ROS have been associated with compromised placental function, impaired fetal development, and increased risk of RPL. Additionally, oxidative stress can modulate maternal immune responses, potentially leading to immune-related pregnancy complications. This review synthesizes current evidence on the mechanisms by which oxidative stress contributes to RPL and highlights emerging research on potential interventions, including antioxidant therapies and lifestyle modifications. Understanding these mechanisms is crucial for developing effective preventive and therapeutic strategies to reduce the risk of RPL and improve pregnancy outcomes. Future research should focus on elucidating the specific pathways involved and exploring novel treatments aimed at mitigating oxidative damage during pregnancy.

Manifestation of polystyrene microplastic accumulation in brain with emphasis on morphometric and histopathological changes in limbic areas of Swiss albino mice

The widespread problem of microplastic (MP) contamination is becoming a major threat to the globe. Although most of the research to date has concentrated on the physiological impacts of MPs exposure, a relatively new field of study is beginning to examine its effects on the behaviour and limbic regions of the brain. In this study, exposure to polystyrene MPs (PS-MPs) for acute and sub-chronic durations negatively affected cognition and induced anxiety-like behaviour in mice. PS-MPs were detected in vital organs of mice, including the brain, which induced neurobehavioural and pathological changes in the limbic system. Furthermore, morphometric analysis revealed a significant decrease in the total cell count in the Dentate Gyrus (DG) and Cornu Ammonis (CA) regions of the hippocampus. Signs of neuronal injury and dystrophic changes were observed in the cortex, amygdala, and hypothalamus, potentially affecting anxiety and fear responses. Our study thus provides insight into the effect of PS-MPs on the neurobiology of the brain's limbic system and related behavioural alterations.

Transcriptomics and metabolomics analyses of graphene oxide toxicity on porcine alveolar macrophages

Graphene oxide (GO) is a type of nanomaterial widely used in tissue engineering, photocatalysis, and biomedicine. GO has been found to produce adverse effects on a broad range of cells and tissues. However, the molecular mechanisms underlying GO toxicity still remain to be explored. In this study, using porcine alveolar macrophages as a study model, we explored the toxic effects of GO and performed genome-wide detection of genes and metabolites associated with GO exposure using RNA-seq and liquid chromatograph mass spectrometer techniques. GO exposure significantly inhibited cell viability and induced apoptosis and oxidative stress in porcine alveolar macrophages. Further, GO exposure promoted cellular inflammation by upregulating the expression of pro-inflammatory cytokines (IL-6, IL-8, and IL-12). Transcriptomic analysis of GO-exposed cells revealed 424 differentially expressed genes. Functional enrichment analysis showed that the differentially expressed genes were significantly enriched in the pathways of Ribosome and oxidative phosphorylation (OXPHOS). In addition, metabolic analysis identified 203 differential metabolites, and these metabolites were significantly enriched in biosynthesis of cofactors, purine metabolism, and nucleotide metabolism. Integrative analyses of transcriptome and metabolome showed that OXPHOS was the most significantly enriched pathway and the involved genes were downregulated. This study revealed the toxic effects of GO on porcine alveolar macrophages and provided global insights to the metabolomic and transcriptomic alterations related to GO exposure. The results contributed to our understanding of the molecular mechanism of GO, and may further promote the detection of biomarkers for the prediction and control of GO toxicity.

Pulmonary Flora-Derived Lipopolysaccharide Mediates Lung-Brain Axis through Activating Microglia Involved in Polystyrene Microplastic-Induced Cognitive Dysfunction

Microplastics (MPs) have been detected in the atmospheric and the human respiratory system, indicating that the respiratory tract is a significant exposure route for MPs. However, the effect of inhaled MPs on cognitive function has not been adequately studied. Here, a C57BL/6 J mouse model of inhalation exposure to polystyrene MPs (PS-MPs, 5 µm, 60 d) is established by intratracheal instillation. Interestingly, in vivo fluorescence imaging and transmission electron microscopy reveal that PS-MPs do not accumulate in the brain. However, behavioral experiments shows that cognitive function of mice is impaired, accompanied by histopathological damage of lung and brain tissue. Transcriptomic studies in hippocampal and lung tissue have demonstrated key neuroplasticity factors as well as cognitive deficits linked to lung injury, respectively. Mechanistically, the lung-brain axis plays a central role in PS-MPs-induced neurological damage, as demonstrated by pulmonary flora transplantation, lipopolysaccharide (LPS) intervention, and cell co-culture experiments. Together, inhalation of PS-MPs reduces cognitive function by altering the composition of pulmonary flora to produce more LPS and promoting M1 polarization of microglia, which provides new insights into the mechanism of nerve damage caused by inhaled MPs and also sheds new light on the prevention of neurotoxicity of environmental pollutants.

Investigation of cell-to-cell transfer of polystyrene microplastics through extracellular vesicle-mediated communication

Plastics are an essential part of human life and their production is increasing every year. Plastics degrade into small particles (<5 mm, microplastics, MPs) in the environment due to various factors. MPs are widely distributed in the environment, and all living organisms are exposed to the effects of MPs. Extracellular vesicles (EVs) are small membrane particles surrounded by a lipid bilayer that are released into the environment by various cell types and are highly involved in inter- and intra-cellular communication through the exchange of proteins, nucleic acids, and lipids between cells. There have been numerous reports of adverse effects associated with the accumulation of MPs in human and animal cells, with recent studies showing that plastic treatment increases the number of EVs released from cells, but the mechanisms by which MPs accumulate and move between cells remain unclear. In this study, we investigated whether polystyrene (PS)-MPs are transferred cell-to-cell via EVs. This study showed that cell-derived EVs can transport plastic particles. Furthermore, we confirmed the accumulation of PS-MPs transported by EVs within cells using a real-time imaging device. This study provides an understanding of potential EVs-mediated effects of PS-MPs on organisms and suggests directions for further research.

Hazardous effects of plastic microfibres from facial masks to aquatic animal health: Insights from zebrafish model

Facial masks are a source of plastic microfibres (PMFs) in the aquatic environment, an emerging risk factor for aquatic organisms. However, little is known concerning its impact during the early developmental stages of fish. Thus, the current study aimed to evaluate the potential interaction and developmental toxicity of PMFs derived from leachate of surgical masks (SC-Msk) and N-95 facial masks (N95-Msk) using a multi-biomarker approach in developing zebrafish (Danio rerio). PMFs from both facial masks were obtained and characterized by multiple techniques. Zebrafish embryos were exposed to environmentally relevant concentrations of PMFs from both facial masks (1000, 10,000, and 100,000 particle L-1), and the toxicity was analysed in terms of mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological changes, reactive oxygen species (ROS) levels, cell viability, and behavioural impairments. The results showed that both facial masks can release PMFs, but the N95-Msk produced a higher concentration of PMFs than SC-Msk. Both PMFs can interact with zebrafish chorion and don't cause effects on embryo mortality and hatching; however, zebrafish embryos showed cardiotoxic effects, and larvae showed increased agitation, average speed, and distance travelled, indicating the behavioural impairments induced by PMFs derived from facial masks. Overall, results showed the risk of PMFs to the health of freshwater fish, indicating the need for greater attention to the disposal and ecotoxicological effects of facial masks on aquatic organisms.

Cobalt nanoparticles attenuate microplastic-induced vascular endothelial injury via Nrf2 pathway activation

The widespread utilization of plastic and cobalt alloy products in industries and medicine has led to the increased presence of their degradation byproducts, microplastics (MPs), and cobalt nanoparticles (Co NPs), in the environment and organisms. While these particles can circulate throughout the body via the circulatory system, their specific adverse effects and mechanisms on the vascular system remain unclear. Employing scanning electron microscope (SEM) analysis and other methodologies, we demonstrate the potential adsorption and aggregation phenomena between MPs and Co NPs. In vitro experiments illustrate that ingestion of either MPs or Co NPs compromises vascular endothelial cell function and induces the generation of reactive oxygen species (ROS). Notably, this effect is markedly attenuated when a combination of MPs and Co NPs is administered compared to MPs alone. Additionally, zebrafish experiments validate our in vitro findings. Mechanistic studies have demonstrated that both MPs and Co NPs induce aberrant Nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. Intriguingly, a weaker activation level is observed when these agents are administered in combination compared to when they are administered individually. Our study provides novel insights into the interaction between MPs and Co NPs and their detrimental effects on vascular endothelial cells.

Concerning influences of micro/nano plastics on female reproductive health: focusing on cellular and molecular pathways from animal models to human studies

The female reproductive system can face serious disorders and show reproductive abnormalities under the influence of environmental pollutants. Microplastics (MPs) and nanoplastics (NPs) as emerging pollutants, by affecting different components of this system, may make female fertility a serious challenge. Animal studies have demonstrated that exposure to these substances weakens the function of ovaries and causes a decrease in ovarian reserve capacity. Also, continuous exposure to micro/nano plastics (MNPs) leads to increased levels of reactive oxygen species, induction of oxidative stress, inflammatory responses, apoptosis of granulosa cells, and reduction of the number of ovarian follicles. Furthermore, by interfering with the hypothalamic-pituitary-ovarian axis, these particles disturb the normal levels of ovarian androgens and endocrine balance and delay the growth of gonads. Exposure to MNPs can accelerate carcinogenesis in the female reproductive system in humans and animal models. Animal studies have determined that these particles can accumulate in the placenta, causing metabolic changes, disrupting the development of the fetus, and endangering the health of future generations. In humans, the presence of micro/nanoplastics in placenta tissue, infant feces, and breast milk has been reported. These particles can directly affect the health of the mother and fetus, increasing the risk of premature birth and other pregnancy complications. This review aims to outline the hazardous effects of micro/nano plastics on female reproductive health and fetal growth and discuss the results of animal experiments and human research focusing on cellular and molecular pathways.

Heat Stress Impairs Endometrial Function During Implantation by Regulating Autophagy in Hainan Black Goat

Heat stress (HS) is a significant factor that adversely affects the health, welfare, and productivity of domestic animals, particularly impacting embryo implantation rates. However, the effects of HS on endometrial function during the peri-implantation period in Hainan black goats remain unclear. This study explores the influence of HS on the endometrium of these goats. We collected uterine tissue samples from both control and heat-stressed goats and performed in vitro experiments using a 2 × 2 factorial design. This design included two temperature conditions (37 °C as the control and 42 °C to simulate heat stress) and two pharmacological treatments: chloroquine (CQ), an autophagy inhibitor, and rapamycin (RAPA), an autophagy activator. Our results showed that heat stress initially suppresses autophagy activity, which is subsequently enhanced with prolonged exposure. The pharmacologic modulation of autophagy, through activation or inhibition, resulted in corresponding upregulation or downregulation of the endometrial epithelial cells' (EECs) receptivity markers. The overexpression of ATG7 partially reversed the HS-induced downregulation of these markers. Additionally, TJP1, a tight-junction marker, was degraded under the pharmacologic and genetic activation of autophagy in HS conditions but accumulated more in the EECs pre-treated with CQ. These findings suggest that autophagy plays a protective role in maintaining endometrial function under HS conditions in Hainan black goats. This study offers valuable insights into the role of autophagy in endometrial receptivity and proposes a potential strategy to mitigate the adverse effects of HS on goat reproduction.

Microplastics exposure disrupts nephrogenesis and induces renal toxicity in human iPSC-derived kidney organoids

Microplastics (MPs) have emerged as a pervasive environmental pollutant of global concern. Their detection within the human placenta and fetal organs has prompted apprehension regarding the potential hazards of MPs during early organogenesis. The kidney, a vital multifunctional organ, is susceptible to damage from MPs in adulthood. However, the precise adverse effects of MP exposure on human nephrogenesis remain ambiguous due to the absence of a suitable model. Here, we explore the potential impact of MPs on early kidney development utilizing human kidney organoids in vitro. Human kidney organoids were subjected to polystyrene-MPs (PS-MPs, 1 μm) during the nephron progenitor cell (NPC) stage, a critical phase in early kidney development and patterning. We delineate the effects of PS-MPs on various stages of nephrogenesis, including NPC, renal vesicle, and comma-shaped body, through sequential examination of kidney organoids. PS-MPs were observed to adhere to the surface of cells during the NPC stage and accumulate within glomerulus-like structures within kidney organoids. Moreover, both short- and long-term exposure to PS-MPs resulted in diminished organoid size and aberrant nephron structure. PS-MP exposure heightened reactive oxygen species (ROS) production, leading to NPC apoptosis during early kidney development. Increased apoptosis, diminished cell viability, and NPC reduction likely contribute to the observed organoid size reduction under PS-MP treatment. Transcriptomic analysis at both NPC and endpoint stages revealed downregulation of Notch signaling, resulting in compromised proximal and distal tubular structures, thereby disrupting normal nephron patterning following PS-MP exposure. Our findings highlight the significant disruptive impact of PS-MPs on human kidney development, offering new insights into the mechanisms underlying PS-MP-induced nephron toxicity.

Maternal exposure to polystyrene nanoplastics induces sex-specific cardiotoxicity in offspring mice

Globally, plastic pollution threatens human health, particularly affecting the hearts of offspring exposed to maternal environmental factors early in development. Few studies have specifically addressed sex-specific cardiac injury in offspring resulting from maternal exposure to polystyrene nanoplastics (PS-NPs). This study investigates the potential cardiac injury in offspring following maternal exposure to 1 mg/L PS-NPs. Pregnant C57BL/6J mice were exposed to PS-NPs until 3 weeks postpartum to establish a maternal exposure model. Heart tissues were collected and weighed, and the transcriptomes of the offspring hearts were sequenced and analyzed using high-throughput RNA sequencing. Immunohistochemical staining was performed to assess the effects of PS-NPs on cardiac immune infiltration, fibrosis, and apoptosis in the offspring. PS-NPs caused a significant reduction in heart and body weight in female offspring compared to males. Additionally, PS-NPs induced sex-specific transcriptional reprogramming and metabolic disruptions in the offspring. PS-NPs also induced significant fibrosis, apoptosis, and increased CD68+ macrophage infiltration in offspring hearts. Notably, PS-NPs induced distinct cardiovascular diseases in the offspring. Fluid shear stress and atherosclerosis were significantly enriched in PS-NP-treated male offspring, while viral myocarditis was predominantly enriched in PS-NP-treated females. Our findings suggest that PS-NPs induce cardiotoxicity in offspring by disrupting metabolism, impairing immunity, and triggering fibrosis and apoptosis, with sex-specific differences. This study provides novel insights and a foundation for understanding sex-specific pharmacological differences and interventions in PS-NP-induced cardiovascular disease in offspring.

Nervous system exposure of different classes of nanoparticles: A review on potential toxicity and mechanistic studies

Nanoparticles (NPs) are generally defined as very small particles in the size range of 1-100 nm. Due to the rapid development of modern society, many new materials have been developed. The widespread use of NPs in medical applications, the food industry and the textile industry has led to an increase in NPs in the environment and the possibility of human contact, which poses a serious threat to human health. The nervous system plays a leading role in maintaining the integrity and unity of the body and maintaining a harmonious balance with the external environment. Therefore, based on two categories of organic and inorganic NPs, this paper systematically summarizes the toxic effects and mechanisms of NPs released into the nervous system. The results showed that exposure to NPs may damage the nervous system, decrease learning and cognitive ability, and affect embryonic development. Finally, a remediation scheme for NPs entering the body via the environment is also introduced. This scheme aims to reduce the neurotoxicity caused by NPs by supplementing NPs with a combination of antioxidant and anti-inflammatory compounds. The results provide a valuable reference for future research in this field.

Intergenerational neurotoxicity of polystyrene nanoplastics in offspring mice is mediated by dysfunctional microbe-gut-brain axis

Nanoplastics (NPs) are ubiquitous in daily life, posing potential risks to the environment and human. While their negative effects on parental organisms have been extensively studied, intergenerational effects are still in the early stages of investigation. Here, we aimed to investigate the impact of maternal exposure to an environmentally relevant level of polystyrene NPs (PSNPs, 100 nm) during gestation and lactation (∼32 days, 50 μg/mouse/day) on neurotoxicity mediated by the microbe-gut-brain axis in offspring mice. Maternal PSNPs exposure significantly increased brain TNF-α level and microglia by 1.43 and 1.48 folds respectively, compared to control, accompanied by nuclear pyknosis and cell vacuolization in cortex and hippocampus. Targeted neurotransmitter metabolomics analysis revealed dysregulation in dopamine and serotonin metabolism. Specifically, dopamine levels increased significantly from 0.007 ng/L to 0.015 ng/L, while N-acetylseroton and 3,4-dihydroxyphenylacetic acid decreased significantly from 0.002 and 0.929 ng/L to 0.001 and 0.680 ng/L, respectively. Through a combination of 16S rRNA sequencing and biochemical analysis, we discovered that maternal PSNPs exposure led to a depletion of anti-inflammatory bacteria and an enrichment of pro-inflammatory bacteria resulting in intestinal barrier damage, elevated levels of lipopolysaccharide in blood, and subsequent activation of neuroinflammation. Meanwhile, gut bacteria dysbiosis interfered with communication between gut and brain by dysregulating neurotransmitter synthesis, as evidenced by significant associations between neurotransmitter-related bacteria (Akkermansia, Family_XIII_AD3011_group, Lachnoclostridium) and dopamine/serotonin related metabolites. Furthermore, transcriptional alterations in dopamine and serotonin related pathways were observed in the enteric nervous system, suggesting abnormal signal transduction from gut to brain contributes to neurotoxicity. This study provides new insights into NPs-induced neurotoxicity within the context of microbe-gut-brain axis and highlights the risk of cerebral dysfunction in offspring with maternal NPs exposure.

Microplastics caused embryonic growth retardation and placental dysfunction in pregnant mice by activating GRP78/IRE1α/JNK axis induced apoptosis and endoplasmic reticulum stress

Microplastics (MPs), a brand-new class of worldwide environmental pollutant, have received a lot of attention. MPs are consumed by both humans and animals through water, food chain and other ways, which may cause potential health risks. However, the effects of MPs on embryonic development, especially placental function, and its related mechanisms still need to be further studied. We investigated the impact on fetal development and placental physiological function of pregnant mice by consecutive gavages of MPs at 0, 25, 50, 100 mg/kg body weight during gestational days (GDs 0-14). The results showed that continuous exposure to high concentrations of MP significantly reduced daily weight gain and impaired reproductive performance of pregnant mice. In addition, MPs could significantly induce oxidative stress and placental dysfunction in pregnant mice. On the other hand, MPs exposure significantly decreased placental barrier function and induced placental inflammation. Specifically, MPs treatment significantly reduced the expression of tight junction proteins in placentas, accompanied by inflammatory cell infiltration and increased mRNA levels of pro-inflammatory cytokines and chemokines in placentas. Finally, we found that MPs induced placental apoptosis and endoplasmic reticulum (ER) stress through the GRP78/IRE1α/JNK axis, leading to placental dysfunction and decreased reproductive performance in pregnant mice. We revealed for the first time that the effects of MPs on placental dysfunction in pregnant animals. Blocking the targets of MPs mediated ER stress will provide potential therapeutic ideas for the toxic effects of MPs on maternal pregnancy.

Micro/nano-plastics impacts in cardiovascular systems across species

The widespread presence of microplastics and nanoplastics (MPs/NPs) in the environment has become a critical public health issue due to their potential to infiltrate and affect various biological systems. Our review is crucial as it consolidates current data and provides a comprehensive analysis of the cardiovascular impacts of MPs/NPs across species, highlighting significant implications for human health. By synthesizing findings from studies on aquatic and terrestrial organisms, including humans, this review offers insights into the ubiquity of MPs/NPs and their pathophysiological roles in cardiovascular systems. We demonstrated that exposure to MPs/NPs is linked to various cardiovascular ailments such as thrombogenesis, vascular damage, and cardiac impairments in model organisms, which likely extrapolate to humans. Our review critically evaluated methods for detecting MPs/NPs in biological tissues, assessing their toxicity, and understanding their behaviour within the vasculature. These findings emphasise the urgent need for targeted public health strategies and enhanced regulatory measures to mitigate the impacts of MP/NP pollution. Furthermore, the review underlined the necessity of advancing research methodologies to explore long-term effects and potential intergenerational consequences of MP/NP exposure. By mapping out the intricate links between environmental exposure and cardiovascular risks, our work served as a pivotal reference for future research and policymaking aimed at curbing the burgeoning threat of plastic pollution.

Polystyrene nanoplastic exposure actives ferroptosis by oxidative stress-induced lipid peroxidation in porcine oocytes during maturation

BACKGROUND

Polystyrene nanoplastics (PS-NPs) are becoming increasingly prevalent in the environment with great advancements in plastic products, and their potential health hazard to animals has received much attention. Several studies have reported the toxicity of PS-NPs to various tissues and cells; however, there is a paucity of information about whether PS-NPs exposure can have toxic effects on mammalian oocytes, especially livestock. Herein, porcine oocytes were used as the model to investigate the potential effects of PS-NPs on mammalian oocytes.

RESULTS

The findings showed that different concentrations of PS-NPs (0, 25, 50 and 100 μg/mL) entering into porcine oocytes could induce mitochondrial stress, including a significant decrease in mitochondrial membrane potential (MMP), and the destruction of the balance of mitochondrial dynamic and micromorphology. Furthermore, there was a marked increase in reactive oxygen species (ROS), which led to oocyte lipid peroxidation (LPO). PS-NPs exposure induced abnormal intracellular iron overload, and subsequently increased the expression of transferrin receptor (TfRC), solute carrier family 7 member 11 (SLC7a11), and acyl-CoA synthetase long-chain family member 4 (ACSL4), which resulted in ferroptosis in oocytes. PS-NPs also induced oocyte maturation failure, cytoskeletal dysfunction and DNA damage. Cotreatment with 5 μmol/L ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) alleviated the cellular toxicity associated with PS-NPs exposure during porcine oocyte maturation.

CONCLUSIONS

In conclusion, PS-NPs caused ferroptosis in porcine oocytes by increasing oxidative stress and altering lipid metabolism, leading to the failure of oocyte maturation.

Maslinic acid supplementation prevents di(2-ethylhexyl) phthalate-induced apoptosis via PRDX6 in peritubular myoid cells of Chinese forest musk deer

Chinese forest musk deer (FMD), an endangered species, have exhibited low reproductive rates even in captivity due to stress conditions. Investigation revealed the presence of di(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, in the serum and skin of captive FMDs. Feeding FMDs with maslinic acid (MA) has been observed to alleviate the stress response and improve reproductive rates, although the precise molecular mechanisms remain unclear. Therefore, this study aims to investigate the molecular mechanisms underlying the alleviation of DEHP-induced oxidative stress and cell apoptosis in primary peritubular myoid cells (PMCs) through MA intake. Primary PMCs were isolated and exposed to DEHP in vitro. The results demonstrated that DEHP significantly suppressed antioxidant levels and promoted cell apoptosis in primary PMCs. Moreover, interfering with the expression of PRDX6 was found to induce excessive reactive oxygen species (ROS) production and cell apoptosis in primary PMCs. Supplementation with MA significantly upregulated the expression of PRDX6, thereby attenuating DEHP-induced oxidative stress and cell apoptosis in primary PMCs. These findings provide a theoretical foundation for mitigating stress levels and enhancing reproductive capacity of in captive FMDs.

Inflammatory response of nanoparticles: Mechanisms, consequences, and strategies for mitigation

Numerous nano-dimensioned materials have been generated as a result of several advancements in nanoscale science such as metallic nanoparticles (mNPs) which have aided in the advancement of related research. As a result, several significant nanoscale materials are being produced commercially. It is expected that in the future, products that are nanoscale, like mNPs, will be useful in daily life. Despite certain benefits, widespread use of metallic nanoparticles and nanotechnology has negative effects and puts human health at risk because of their continual accumulation in closed biological systems, along with their complex and diverse migratory and transformation pathways. Once within the human body, nanoparticles (NPs) disrupt the body's natural biological processes and trigger inflammatory responses. These NPs can also affect the immune system by activating separate pathways that either function independently or interact with one another. Cytotoxic effects, inflammatory response, genetic material damage, and mitochondrial dysfunction are among the consequences of mNPs. Oxidative stress and reactive oxygen species (ROS) generation caused by mNPs depend upon a multitude of factors that allow NPs to get inside cells and interact with biological macromolecules and cell organelles. This review focuses on how mNPs cause inflammation and oxidative stress, as well as disrupt cellular signaling pathways that support these effects. In addition, possibilities and problems to be reduced are addressed to improve future research on the creation of safer and more environmentally friendly metal-based nanoparticles for commercial acceptance and sustainable use in medicine and drug delivery.

The Impact of Maternal Nanoplastic and Microplastic Particle Exposure on Mammal's Offspring

The issue of environmental nanoplastic (NPl) particle and microplastic (MPl) particle pollution is becoming increasingly severe, significantly impacting ecosystems and biological health. Research shows that NPl/MPl can penetrate the placental barrier and enter the fetus, leading to transgenerational effects. This review integrates the existing literature on the effects of prenatal NPl/MPl exposure on mammalian offspring, focusing particularly on its negative impacts on the central nervous system, liver, intestinal health, reproductive function, and skeletal muscles. The vast majority of previous studies on prenatal NPl/MPl in mammals have used polystyrene material. Future research should explore the effects of other prenatal NPl/MPl materials on offspring to better reflect the realities of the human environment. It is also essential to investigate the potential harm and underlying mechanisms associated with prenatal NPl/MPl exposure to offspring in greater depth. This will aid in developing appropriate prevention and treatment strategies in the future.

Effects of nanoplastic exposure during pregnancy and lactation on neurodevelopment of rat offspring

Microplastics have emerged as a prominent global environmental contaminant, and they have been found in both human placenta and breast milk. However, the potential effects and mechanisms of maternal exposure to microplastics at various gestational stages on offspring neurodevelopment remain poorly understood. This investigation delves into the potential neurodevelopmental ramifications of maternal exposure to polystyrene nanoplastics (PS-NPs) during distinct phases of pregnancy and lactation. Targeted metabolomics shows that co-exposure during both pregnancy and lactation primarily engendered alterations in monoamine neurotransmitters within the cortex and amino acid neurotransmitters within the hippocampus. After prenatal exposure to PS-NPs, fetal rats showed appreciably diminished cortical thickness and heightened cortical cell proliferation. However, this exposure did not affect the neurodifferentiation of radial glial cells and intermediate progenitor cells. In addition, offspring are accompanied by disordered neocortical migration, typified by escalated superficial layer neurons proliferation and reduced deep layer neurons populations. Moreover, the hippocampal synapses showed significantly widened synaptic clefts and diminished postsynaptic density. Consequently, PS-NPs culminated in deficits in anxiolytic-like behaviors and spatial memory in adolescent offspring, aligning with concurrent neurotransmitter and synaptic alterations. In conclusion, this study elucidates the sensitive windows of early-life nanoplastic exposure and the consequential impact on offspring neurodevelopment.

Combined exposure of PS-MPs with NaF induces Sertoli cell death and dysfunction via ferroptosis and apoptosis

The individual toxicity of sodium fluoride (NaF) and microplastics (MPs) has been extensively documented. Owing to their high specific surface area, widespread presence and durability, MPs can adsorb a broad spectrum of environmental contaminants into the organism. However, the combined toxicity of NaF and MPs has not been investigated. This study aimed to assess the effects of combined exposure to NaF and MPs on the function of testicular Sertoli cells (SCs) in male mice, and to investigate the underlying molecular mechanisms. The study revealed that combined exposure to NaF and MPs resulted in a decrease in the negative surface charge of MPs, along with an increase in the number of MPs entering the SCs. Through in vivo observation of the testicular pathological structure, spermatogenesis, and cell apoptosis in 180-day-old male mice, we discovered that combined exposure to NaF (80 mg/L) and MPs (10 mg/L) heightened reproductive toxicity compared to the individual exposure groups. This was evidenced by testicular structural defects, impaired spermatogenesis, and increased testicular cell apoptosis. Our in vitro studies showed that NaF (21 μg/mL) and MPs (100 μg/mL) synergistically induced SCs apoptosis and ferroptosis, leading to a reduction in SCs number and dysfunction. This ultimately resulted in structural and functional damage to the testes. Our findings demonstrate, for the first time, the synergistic effects of NaF and MPs on reproductive toxicity in mammals. These insights may provide valuable contributions to co-toxicity studies involving MPs and other environmental pollutants.

Effects of polystyrene nanoplastic size on zebrafish embryo development

Polystyrene nanoplastics (PS) require a comprehensive evaluation of their toxicity and potential risks to humans and the environment. The zebrafish model, a well-established animal model increasingly utilized for nanotoxicity assessments, was employed in this study. Our research aimed to explore the toxic effects of PS with sizes of 30, 100, 200, and 450 nm on zebrafish embryos. Exposure experiments were conducted on embryos at 4 h post-fertilization (hpf) using various concentrations of nanoparticles (20, 40, 60, 80, and 100 mg/L) until 96 hpf. Notably, PS ranging from 100 to 450 nm did not adversely affect zebrafish embryo development. However, PS with a size of 30 nm at a concentration of 100 mg/L resulted in embryo mortality but not embryonic malformations. Furthermore, our investigation confirmed the uptake of these nanoparticles by zebrafish larvae following the opening of their mouths, with the particles being found predominantly in the digestive system of the larvae. Additionally, 30 nm PS were found to significantly modulate the expression levels of genes associated with oxidative stress and apoptosis. These findings highlight the developmental impacts of 30 nm PS on zebrafish embryos, raising concerns about potential similar consequences in humans. Considering our findings, it is essential to encourage further research into the management and regulation of PS to mitigate their potential environmental and health impacts.

A review on micro- and nanoplastics in humans: Implication for their translocation of barriers and potential health effects

As emerging contaminants, micro- and nanoplastics (MNPs) can absorb and leach various toxic chemicals and ultimately endanger the health of the ecological environment and humans. With extensive research on MNPs, knowledge about MNPs in humans, especially their translocation of barriers and potential health effects, is of utmost importance. In this review, we collected literature published from 2000 to 2023, focusing on MNPs on their occurrence in humans, penetrating characteristics in the placental, blood-brain, and blood-testis barriers, and exposure effects on mammalian health. The characteristics and distributions of MNPs in human samples were analyzed, and the results demonstrated that MNPs were ubiquitous in most human samples, except for kidneys and cerebrospinal fluid. In addition, the phenomenon of MNPs crossing barriers and their underlying mechanisms were discussed. We also summarized the potential factors that may affect the barrier crossing and health effects of MNPs, including characteristics of MNPs, exposure doses, administration routes, exposure durations, co-exposure to other pollutants, and genetic predisposition. Exposure to MNPs may cause cytotoxicity, neurotoxicity, and developmental and reproductive toxicity in mammals. People are encouraged to reduce their exposure to MNPs to prevent these adverse health effects. Finally, we discussed the shortcomings of current research on MNPs in humans, providing a valuable reference for understanding and evaluating the potential health risks from MNP exposure in mammals, including humans.

Micro/Nanoplastic Exposure on Placental Health and Adverse Pregnancy Risks: Novel Assessment System Based upon Targeted Risk Assessment Environmental Chemicals Strategy

Micro/nanoplastics (MNPs), as emerging pollutants, have been detected in both the maternal and fetal sides of the placenta in pregnant women, and their reproductive toxicity has been demonstrated in in vivo and in vitro experimental models. The Targeted Risk Assessment of Environmental Chemicals (TRAEC) strategy has been innovatively devised to facilitate valid risk assessment, encompassing a comprehensive evaluation of reliability, correlation, outcome fitness, and integrity across four dimensions based on the included published evidence and our own findings. This study serves as an application case of TRAEC, with 40 items of research evidence on the toxicity of MNPs to the placenta, which were rigorously screened and incorporated into the final scoring system. The final score for this TRAEC case study is 5.63, suggesting a moderate-to-low risk of reproductive toxicity associated with MNPs in the placenta, which may potentially increase with decreasing particle size. It is essential to emphasize that the findings also report original data from assays indicating that exposure to high-dose groups (100 μg/mL, 200 μg/mL) of 50 nm and 200 nm polystyrene nanoplastics (PS-NPs) induces HTR8/SVneo cell cycle arrest and cell apoptosis, which lead to reproductive toxicity in the placenta by disrupting mitochondrial function. Overall, this study employed the TRAEC strategy to provide comprehensive insight into the potential reproductive health effects of ubiquitous MNPs.

Polystyrene Nanoplastics Induce Lipid Metabolism Disorder by Activating the PERK-ATF4 Signaling Pathway in Mice

In recent years, the study of microplastics (MPs) and nanoplastics (NPs) and their effects on human health has gained significant attention. The impacts of NPs on lipid metabolism and the specific mechanisms involved remain poorly understood. To address this, we utilized high-throughput sequencing and molecular biology techniques to investigate how endoplasmic reticulum (ER) stress might affect hepatic lipid metabolism in the presence of polystyrene nanoplastics (PS-NPs). Our findings suggest that PS-NPs activate the PERK-ATF4 signaling pathway, which in turn upregulates the expression of genes related to lipid synthesis via the ATF4-PPARγ/SREBP-1 pathway. This activation leads to an abnormal accumulation of lipid droplets in the liver. 4-PBA, a known ER stress inhibitor, was found to mitigate the PS-NPs-induced lipid metabolism disorder. These results demonstrate the hepatotoxic effects of PS-NPs and clarify the mechanisms of abnormal lipid metabolism induced by PS-NPs.

Research Progress on Micro(nano)plastic-Induced Programmed Cell Death Associated with Disease Risks

Due to their robust migration capabilities, slow degradation, and propensity for adsorbing environmental pollutants, micro(nano)plastics (MNPs) are pervasive across diverse ecosystems. They infiltrate various organisms within different food chains through multiple pathways including inhalation and dermal contact, and pose a significant environmental challenge in the 21st century. Research indicates that MNPs pose health threats to a broad range of organisms, including humans. Currently, extensive detection data and studies using experimental animals and in vitro cell culture indicate that MNPs can trigger various forms of programmed cell death (PCD) and can induce various diseases. This review provides a comprehensive and systematic analysis of different MNP-induced PCD processes, including pyroptosis, ferroptosis, autophagy, necroptosis, and apoptosis, based on recent research findings and focuses on elucidating the links between PCD and diseases. Additionally, targeted therapeutic interventions for these diseases are described. This review provides original insights into the opportunities and challenges posed by current research findings. This review evaluates ways to mitigate various diseases resulting from cell death patterns. Moreover, this paper enhances the understanding of the biohazards associated with MNPs by providing a systematic reference for subsequent toxicological research and health risk mitigation efforts.

Selective bioaccumulation of polystyrene nanoplastics in fetal rat brain and damage to myelin development

Micro(nano)plastic, as a new type of environmental pollutant, have become a potential threat to the life and health of various stages of biology. However, it is not yet clear whether they will affect brain development in the fetal stage. Therefore, this study aims to explore the potential effects of nanoplastics on the development of fetal rat brains. To assess the allocation of NPs (25 nm and 50 nm) in various regions of the fetal brain, pregnant rats were exposed to concentrations (50, 10, 2.5, and 0.5 mg/kg) of PS-NPs. Our results provided evidence of the transplacental transfer of PS-NPs to the fetal brain, with a prominent presence observed in several cerebral regions, notably the cerebellum, hippocampus, striatum, and prefrontal cortex. This distribution bias might be linked to the developmental sequence of each brain region. Additionally, we explored the influence of prenatal exposure on the myelin development of the cerebellum, given its the highest PS-NP accumulation in offspring. Compared with control rats, PS-NPs exposure caused a significant reduction in myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) expression, a decrease in myelin thickness, an increase in cell apoptosis, and a decline in the oligodendrocyte population. These effects gave rise to motor deficits. In conclusion, our results identified the specific distribution of NPs in the fetal brain following prenatal exposure and revealed that prenatal exposure to PS-NPs can suppress myelin formation in the cerebellum of the fetus.

Reactive Oxygen Species-Mediated Mitophagy and Cell Apoptosis are Involved in the Toxicity of Aluminum Chloride Exposure in GC-2spd

Aluminum chloride is an inorganic polymeric coagulant commonly found in daily life and various materials. Although male reproductive toxicity has been associated with AlCl3 exposure, the underlying mechanism remains unclear. This study aimed to examine the impact of AlCl3 exposure on mitophagy and mitochondrial apoptosis in testicular tissue and mouse spermatocytes. Reactive oxygen species (ROS) and ATP levels were measured in GC-2spd after AlCl3 exposure using a multifunctional enzyme labeler. The changes in mitochondrial membrane potential (MMP) and TUNEL were observed through confocal laser microscopy, and the expression of proteins associated with mitophagy and apoptosis was analyzed using Western blot. Our results demonstrated that AlCl3 exposure disrupted mitophagy and increased apoptosis-related protein expression in testicular tissues. In the in vitro experiments, AlCl3 exposure induced ROS production, suppressed cell viability and ATP production, and caused a decrease in MMP, leading to mitophagy and cell apoptosis in GC-2spd cells. Intervention with N-acetylcysteine (NAC) reduced ROS production and partially restored mitochondrial function, thereby reversing the resulting mitophagy and cell apoptosis. Our findings provide evidence that ROS-mediated mitophagy and cell apoptosis play a crucial role in the toxicity of AlCl3 exposure in GC-2spd. These results contribute to the understanding of male reproductive toxicity caused by AlCl3 exposure and offer a foundation for future research in this area.