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Journal of Hazardous Materials Feb 2022Plastics have caused serious environmental pollution. In recent years, microplastics (MPs) have caused widespread concern about their potential toxicity on animals and...
Plastics have caused serious environmental pollution. In recent years, microplastics (MPs) have caused widespread concern about their potential toxicity on animals and humans, especially on organ and tissue deposition. However, there is little known about the reproductive toxic effects of MPs in female mammals. In this study, the reproductive toxicity of polystyrene MPs (PS-MPs) in female mice was evaluated after continued exposure for 35 days. Results showed that PS-MPs could accumulate in heart, liver, spleen, lung, kidney, brain, large intestine, small intestine, uterus, ovary and blood of exposed mice. Moreover, PS-MPs exposure increased the IL-6 level and decreased malondialdehyde (MDA) level in mouse ovaries. The results also showed that PS-MPs exposure decreased the first polar body extrusion rate and the survival rate of superovulated oocytes. Meanwhile, PS-MPs reduced the level of glutathione (GSH), mitochondrial membrane potential (MMP), endoplasmic reticulum calcium ([Ca]) and increased reactive oxygen species (ROS) in oocytes. In conclusion, our study illustrated that PS-MPs exposure induced the inflammation of ovaries and reduced the quality of oocytes in mice, which provided a basis for studying the reproductive toxic mechanism of PS-MPs in female mammals.
Topics: Animals; Female; Mice; Microplastics; Plastics; Polystyrenes; Reactive Oxygen Species; Reproduction; Water Pollutants, Chemical
PubMed: 34740508
DOI: 10.1016/j.jhazmat.2021.127629 -
Environment International May 2022Plastic particles are ubiquitous pollutants in the living environment and food chain but no study to date has reported on the internal exposure of plastic particles in...
Plastic particles are ubiquitous pollutants in the living environment and food chain but no study to date has reported on the internal exposure of plastic particles in human blood. This study's goal was to develop a robust and sensitive sampling and analytical method with double shot pyrolysis - gas chromatography/mass spectrometry and apply it to measure plastic particles ≥700 nm in human whole blood from 22 healthy volunteers. Four high production volume polymers applied in plastic were identified and quantified for the first time in blood. Polyethylene terephthalate, polyethylene and polymers of styrene (a sum parameter of polystyrene, expanded polystyrene, acetonitrile butadiene styrene etc.) were the most widely encountered, followed by poly(methyl methacrylate). Polypropylene was analysed but values were under the limits of quantification. In this study of a small set of donors, the mean of the sum quantifiable concentration of plastic particles in blood was 1.6 µg/ml, showing a first measurement of the mass concentration of the polymeric component of plastic in human blood. This pioneering human biomonitoring study demonstrated that plastic particles are bioavailable for uptake into the human bloodstream. An understanding of the exposure of these substances in humans and the associated hazard of such exposure is needed to determine whether or not plastic particle exposure is a public health risk.
Topics: Environmental Monitoring; Humans; Plastics; Polymers; Polystyrenes; Pyrolysis; Water Pollutants, Chemical
PubMed: 35367073
DOI: 10.1016/j.envint.2022.107199 -
The American Journal of Emergency... Feb 2022Hyperkalemia represents a widespread and potentially lethal condition that affects millions of people across their lives. Despite the prevalence and severity of the... (Review)
Review
Hyperkalemia represents a widespread and potentially lethal condition that affects millions of people across their lives. Despite the prevalence and severity of the condition, there are no consensus guidelines on the treatment of hyperkalemia or even a standard definition. Herein, we provide a succinct review of what we believe to be the most significant misconceptions encountered in the emergency care of hyperkalemia, examine current available literature, and discuss practical points on several modalities of hyperkalemia treatment. Additionally, we review the pathophysiology of the electrocardiographic effects of hyperkalemia and how intravenous calcium preparations can antagonize these effects. We conclude each section with recommendations to aid emergency physicians in making safe and efficacious choices for the treatment of acute hyperkalemia.
Topics: Calcium; Calcium-Regulating Hormones and Agents; Cation Exchange Resins; Electrocardiography; Emergency Service, Hospital; Humans; Hyperkalemia; Polystyrenes; Ringer's Lactate
PubMed: 34890894
DOI: 10.1016/j.ajem.2021.11.030 -
Journal of Hazardous Materials May 2022Microplastics (MPs) pollution has become a serious environmental issue worldwide, but its potential effects on health remain unknown. The administration of polystyrene...
Microplastics (MPs) pollution has become a serious environmental issue worldwide, but its potential effects on health remain unknown. The administration of polystyrene MPs (PS-MPs) to mice for eight weeks impaired learning and memory behavior. PS-MPs were detected in the brain especially in the hippocampus of these mice. Concurrently, the hippocampus had decreased levels of immediate-early genes, aberrantly enhanced synaptic glutamate AMPA receptors, and elevated neuroinflammation, all of which are critical for synaptic plasticity and memory. Interestingly, ablation of the vagus nerve, a modulator of the gut-brain axis, improved the memory function of PS-MPs mice. These results indicate that exposure to PS-MPs in mice alters the expression of neuronal activity-dependent genes and synaptic proteins, and increases neuroinflammation in the hippocampus, subsequently causing behavioral changes through the vagus nerve-dependent pathway. Our findings shed light on the adverse impacts of PS-MPs on the brain and hippocampal learning and memory.
Topics: Animals; Glutamic Acid; Hippocampus; Mice; Microplastics; Plastics; Polystyrenes
PubMed: 35150991
DOI: 10.1016/j.jhazmat.2022.128431 -
Environment International Aug 2022The adverse effects of plastic on adult animal and human health have been receiving increasing attention. However, its potential toxicity to fetuses has not been fully...
The adverse effects of plastic on adult animal and human health have been receiving increasing attention. However, its potential toxicity to fetuses has not been fully elucidated. Herein, biodistribution of polystyrene (PS) particles was determined after the maternal mice were orally given PS micro- and/or nano-particles with and without surface modifications during gestational days 1 to 17. The results showed that PS microplastics (MPs) and nanoparticles (NPs) mainly emerged in the alimentary tract, brain, uterus, and placenta in maternal mice, and only the latter infiltrated into the fetal thalamus. PS NPs and carboxyl-modified NPs induced differentially expressed genes mainly enriched in oxidative phosphorylation and GABAergic synapse. Maternal administration of PS particles during gestation led to anxiety-like behavior of the progenies and their γ-aminobutyric acid (GABA) reduction in the prefrontal cortex and amygdala at Week 8. N-Acetylcysteine (NAC), an antioxidant, alleviated PS particles-induced oxidative injury in the fetal brain and rescued the anxiety-like behavior of the progenies. Additionally, PS nanoparticles caused excessive ROS and apoptosis in neuronal cell lines, which were prevented by glutathione supplementation. These results suggested that PS particles produced a negative effect on fetuses by inducing oxidative injury and suppressing GABA synthesis in their brain. The findings contribute to estimating the risk for PS particles to human and animal health.
Topics: Pregnancy; Female; Humans; Animals; Mice; Polystyrenes; Plastics; Reactive Oxygen Species; Tissue Distribution; Fetus; Apoptosis; gamma-Aminobutyric Acid; Nanoparticles; Water Pollutants, Chemical
PubMed: 35749991
DOI: 10.1016/j.envint.2022.107362 -
Particle and Fibre Toxicology Feb 2022Microplastics (MPs), which are smaller in size and difficult to degrade, can be easily ingested by marine life and enter mammals through the food chain. Our previous...
BACKGROUND
Microplastics (MPs), which are smaller in size and difficult to degrade, can be easily ingested by marine life and enter mammals through the food chain. Our previous study demonstrated that following acute exposure to MPs, the serum testosterone content reduced and sperm quality declined, resulting in male reproductive dysfunction in mice. However, the toxic effect of long-term exposure to MPs at environmental exposure levels on the reproductive system of mammals remains unclear.
RESULTS
In vivo, mice were given drinking water containing 100 μg/L and 1000 μg/L polystyrene MPs (PS-MPs) with particle sizes of 0.5 μm, 4 μm, and 10 μm for 180 consecutive days. We observed alterations in testicular morphology and reductions in testosterone, LH and FSH contents in serum. In addition, the viability of sperm was declined and the rate of sperm abnormality was increased following exposure to PS-MPs. The expression of steroidogenic enzymes and StAR was downregulated in testis tissues. In vitro, we used primary Leydig cells to explore the underlying mechanism of the decrease in testosterone induced by PS-MPs. First, we discovered that PS-MPs attached to and became internalized by Leydig cells. And then we found that the contents of testosterone in the supernatant declined. Meanwhile, LHR, steroidogenic enzymes and StAR were downregulated with concentration-dependent on PS-MPs. We also confirmed that PS-MPs decreased StAR expression by inhibiting activation of the AC/cAMP/PKA pathway. Moreover, the overexpression of LHR alleviated the reduction in StAR and steroidogenic enzymes levels, and finally alleviated the reduction in testosterone induced by PS-MPs.
CONCLUSIONS
PS-MPs exposure resulted in alterations in testicular histology, abnormal spermatogenesis, and interference of serum hormone secretion in mice. PS-MPs induced a reduction in testosterone level through downregulation of the LH-mediated LHR/cAMP/PKA/StAR pathway. In summary, our study showed that chronic exposure to PS-MPs resulted in toxicity of male reproduction under environmental exposure levels, and these potential risks may ring alarm bells of public health.
Topics: Animals; Male; Mammals; Mice; Microplastics; Plastics; Polystyrenes; Reproduction; Testosterone
PubMed: 35177090
DOI: 10.1186/s12989-022-00453-2 -
Environmental Health Perspectives Oct 2022The toxicity of microplastics (MPs) has attracted wide attention from researchers. Previous studies have indicated that MPs produce toxic effects on a variety of organs...
BACKGROUND
The toxicity of microplastics (MPs) has attracted wide attention from researchers. Previous studies have indicated that MPs produce toxic effects on a variety of organs in aquatic organisms and mammals. However, the exact neurotoxicity of MPs in mammals is still unclear.
OBJECTIVES
We aimed to confirm the neurotoxicity of chronic exposure to polystyrene MPs (PS-MPs) at environmental pollution concentrations.
METHODS
In the present study, mice were provided drinking water containing and PS-MPs with diameters of 0.5, 4, and for 180 consecutive days. After the exposure period, the mice were anesthetized to gain brain tissues. The accumulation of PS-MPs in brain tissues, integrity of the blood-brain barrier, inflammation, and spine density were detected. We evaluated learning and memory ability by the Morris water maze and novel object recognition tests.
RESULTS
We observed the accumulation of PS-MPs with various particle diameters (0.5, 4, and ) in the brains of exposed mice. Meanwhile, exposed mice also exhibited disruption of the blood-brain barrier, higher level of dendritic spine density, and an inflammatory response in the hippocampus. In addition, exposed mice exhibited cognitive and memory deficits compared with control mice as determined using the Morris water maze and novel object recognition tests, respectively. There was a concentration-dependent trend, but no particle size-dependent differences were seen in the neurotoxicity of MPs.
CONCLUSIONS
Collectively, our results suggested that PS-MPs exposure can lead to learning and memory dysfunctions and induce neurotoxic effects in mice, findings which have wide-ranging implications for the public regarding the potential risks of MPs. https://doi.org/10.1289/EHP10255.
Topics: Animals; Drinking Water; Mammals; Mice; Mice, Inbred BALB C; Microplastics; Neurotoxicity Syndromes; Plastics; Polystyrenes; Water Pollutants, Chemical
PubMed: 36251724
DOI: 10.1289/EHP10255 -
Particle and Fibre Toxicology Oct 2020Plastic is everywhere. It is used in food packaging, storage containers, electronics, furniture, clothing, and common single-use disposable items. Microplastic and...
BACKGROUND
Plastic is everywhere. It is used in food packaging, storage containers, electronics, furniture, clothing, and common single-use disposable items. Microplastic and nanoplastic particulates are formed from bulk fragmentation and disintegration of plastic pollution. Plastic particulates have recently been detected in indoor air and remote atmospheric fallout. Due to their small size, microplastic and nanoplastic particulate in the atmosphere can be inhaled and may pose a risk for human health, specifically in susceptible populations. When inhaled, nanosized particles have been shown to translocate across pulmonary cell barriers to secondary organs, including the placenta. However, the potential for maternal-to-fetal translocation of nanosized-plastic particles and the impact of nanoplastic deposition or accumulation on fetal health remain unknown. In this study we investigated whether nanopolystyrene particles can cross the placental barrier and deposit in fetal tissues after maternal pulmonary exposure.
RESULTS
Pregnant Sprague Dawley rats were exposed to 20 nm rhodamine-labeled nanopolystyrene beads (2.64 × 10 particles) via intratracheal instillation on gestational day (GD) 19. Twenty-four hours later on GD 20, maternal and fetal tissues were evaluated using fluorescent optical imaging. Fetal tissues were fixed for particle visualization with hyperspectral microscopy. Using isolated placental perfusion, a known concentration of nanopolystyrene was injected into the uterine artery. Maternal and fetal effluents were collected for 180 min and assessed for polystyrene particle concentration. Twenty-four hours after maternal exposure, fetal and placental weights were significantly lower (7 and 8%, respectively) compared with controls. Nanopolystyrene particles were detected in the maternal lung, heart, and spleen. Polystyrene nanoparticles were also observed in the placenta, fetal liver, lungs, heart, kidney, and brain suggesting maternal lung-to-fetal tissue nanoparticle translocation in late stage pregnancy.
CONCLUSION
These studies confirm that maternal pulmonary exposure to nanopolystyrene results in the translocation of plastic particles to placental and fetal tissues and renders the fetoplacental unit vulnerable to adverse effects. These data are vital to the understanding of plastic particulate toxicology and the developmental origins of health and disease.
Topics: Animals; Female; Fetus; Humans; Inhalation Exposure; Maternal Exposure; Maternal-Fetal Exchange; Particle Size; Placenta; Plastics; Polystyrenes; Pregnancy; Rats; Rats, Sprague-Dawley
PubMed: 33099312
DOI: 10.1186/s12989-020-00385-9 -
Environmental Health Perspectives Feb 2023Microplastics (MPs) are small particles of plastic ( in diameter). In recent years, oral exposure to MPs in living organisms has been a cause of concern. Leaky gut...
BACKGROUND
Microplastics (MPs) are small particles of plastic ( in diameter). In recent years, oral exposure to MPs in living organisms has been a cause of concern. Leaky gut syndrome (LGS), associated with a high-fat diet (HFD) in mice, can increase the entry of foreign substances into the body through the intestinal mucosa.
OBJECTIVES
We aimed to evaluate the pathophysiology of intestinal outcomes associated with consuming a high-fat diet and simultaneous intake of MPs, focusing on endocrine and metabolic systems.
METHODS
C57BL6/J mice were fed a normal diet (ND) or HFD with or without polystyrene MP for 4 wk to investigate differences in glucose tolerance, intestinal permeability, gut microbiota, as well as metabolites in serum, feces, and liver.
RESULTS
In comparison with HFD mice, mice fed the HFD with MPs had higher blood glucose, serum lipid concentrations, and nonalcoholic fatty liver disease (NAFLD) activity scores. Permeability and goblet cell count of the small intestine (SI) in HFD-fed mice were higher and lower, respectively, than in ND-fed mice. There was no obvious difference in the number of inflammatory cells in the SI lamina propria between mice fed the ND and mice fed the ND with MP, but there were more inflammatory cells and fewer anti-inflammatory cells in mice fed the HFD with MPs in comparison with mice fed the HFD without MPs. The expression of genes related to inflammation, long-chain fatty acid transporter, and cotransporter was significantly higher in mice fed the HFD with MPs than in mice fed the HFD without MPs. Furthermore, the genus was significantly more abundant in the intestines of mice fed the HFD with MPs in comparison with mice fed the HFD without MPs. gene expression was decreased when palmitic acid and microplastics were added to the murine intestinal epithelial cell line MODE-K cells, and Muc2 gene expression was increased when IL-22 was added.
DISCUSSION
Our findings suggest that in this study, MP induced metabolic disturbances, such as diabetes and NAFLD, only in mice fed a high-fat diet. These findings suggest that LGS might have been triggered by HFD, causing MPs to be deposited in the intestinal mucosa, resulting in inflammation of the intestinal mucosal intrinsic layer and thereby altering nutrient absorption. These results highlight the need for reducing oral exposure to MPs through remedial environmental measures to improve metabolic disturbance under high-fat diet conditions. https://doi.org/10.1289/EHP11072.
Topics: Animals; Mice; Non-alcoholic Fatty Liver Disease; Microplastics; Polystyrenes; Plastics; Diet, High-Fat; Liver; Inflammation; Glucose; Mice, Inbred C57BL
PubMed: 36821708
DOI: 10.1289/EHP11072 -
Environmental Health Perspectives May 2021Understanding the epidemic of chronic kidney disease of uncertain etiology may be critical for health policies and public health responses. Recent studies have shown...
BACKGROUND
Understanding the epidemic of chronic kidney disease of uncertain etiology may be critical for health policies and public health responses. Recent studies have shown that microplastics (MPs) contaminate our food chain and accumulate in the gut, liver, kidney, muscle, and so on. Humans manufacture many plastics-related products. Previous studies have indicated that particles of these products have several effects on the gut and liver. Polystyrene (PS)-MPs (PS-MPs) induce several responses, such as oxidative stress, and affect living organisms.
OBJECTIVES
The aim of this study was to investigate the effects of PS-MPs in kidney cells and .
METHODS
PS-MPs were evaluated in human kidney proximal tubular epithelial cells (HK-2 cells) and male C57BL/6 mice. Mitochondrial reactive oxygen species (ROS), endoplasmic reticulum (ER) stress, inflammation, and autophagy were analyzed in kidney cells. , we evaluated biomarkers of kidney function, kidney ultrastructure, muscle mass, and grip strength, and urine protein levels, as well as the accumulation of PS-MPs in the kidney tissue.
RESULTS
Uptake of PS-MPs at different concentrations by HK-2 cells resulted in higher levels of mitochondrial ROS and the mitochondrial protein Bad. Cells exposed to PS-MPs had higher ER stress and markers of inflammation. MitoTEMPO, which is a mitochondrial ROS antioxidant, mitigated the higher levels of mitochondrial ROS, Bad, ER stress, and specific autophagy-related proteins seen with PS-MP exposure. Furthermore, cells exposed to PS-MPs had higher protein levels of LC3 and Beclin 1. PS-MPs also had changes in phosphorylation of mitogen-activated protein kinase (MAPK) and protein kinase B (AKT)/mitogen-activated protein kinase (mTOR) signaling pathways. In an study, PS-MPs accumulated and the treated mice had more histopathological lesions in the kidneys and higher levels of ER stress, inflammatory markers, and autophagy-related proteins in the kidneys after PS-MPs treatment by oral gavage.
CONCLUSIONS
The results suggest that PS-MPs caused mitochondrial dysfunction, ER stress, inflammation, and autophagy in kidney cells and accumulated in HK-2 cells and in the kidneys of mice. These results suggest that long-term PS-MPs exposure may be a risk factor for kidney health. https://doi.org/10.1289/EHP7612.
Topics: Animals; Epithelial Cells; Humans; Kidney; Male; Mice; Mice, Inbred C57BL; Microplastics; Polystyrenes
PubMed: 33956507
DOI: 10.1289/EHP7612