Polyethylene microplastics cause apoptosis via the MiR-132/CAPN axis and inflammation in carp ovarian

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.

Green tea polyphenols alleviate TBBPA-induced gastric inflammation and apoptosis by modulating the ROS-PERK/IRE-1/ATF6 pathway in mouse models

Green tea polyphenols (GTP), an important phytochemical in the daily human diet, bind to various cellular receptors and exert anti-inflammatory and antioxidant benefits. The environmental contaminant tetrabromobisphenol A (TBBPA) enters the digestive system through multiple pathways, resulting in oxidative stress (OS), gastroenteritis, and mucosal injury. The aim of this study was to explore the molecular mechanisms of TBBPA-induced gastritis in mice treated with GTP in vivo and in an in vitro model. The results showed that exposure to TBBPA increased reactive oxygen species (ROS) levels, activated oxidative stress (OS) induced endoplasmic reticulum stress (ERS), and the expression of endoplasmic reticulum stress-related factors (e.g., GRP78, PERK, IRE-1, ATF-6, etc.) increased. The inflammatory pathway NF-κB was activated, and the pro-inflammatory factors TNF-α, IL-1β, and IL-6 increased, while triggering a cascade reaction mediated by caspase-3. However, the addition of GTP could inhibit OS, restore the balance of endoplasmic reticulum homeostasis, and improve the inflammatory infiltration and apoptosis of gastric mucosal epithelial cells. Therefore, GTP alleviated ERS, reduced inflammation and apoptosis, and restored the gastric mucosal barrier by alleviating TBBPA-induced OS in mouse gastric tissues and GES-1 cells. This provides basic information for exploring the antioxidant mechanism of GTP and further investigating the toxic effects of TBBPA on mouse gastric mucosa.

Potential mechanisms of aortic medial degeneration promoted by co-exposure to microplastics and lead

Microplastics (MPs) have attracted widespread attention because they can lead to combined toxicity by adsorbing heavy metals from the environment. Exposure to lead (Pb), a frequently adsorbed heavy metal by MPs, is common. In the current study, the coexistence of MPs and Pb was assessed in human samples. Then, mice were used as models to examine how co-exposure to MPs and Pb promotes aortic medial degeneration. The results showed that MPs and Pb co-exposure were detected in patients with aortic disease. In mice, MPs and Pb co-exposure promoted the damage of elastic fibers, loss of vascular smooth muscle cells (VSMCs), and release of inflammatory factors. In vitro cell models revealed that co-exposure to MPs and Pb induced excessive reactive oxygen species generation, impaired mitochondrial function, and triggered PANoptosome assembly in VSMCs. These events led to PANoptosis and inflammation through the cAMP/PKA-ROS signaling pathway. However, the use of the PKA activator 8-Br-cAMP or mitochondrial ROS scavenger Mito-TEMPO improved, mitochondrial function in VSMCs, reduced cell death, and inhibited inflammatory factor release. Taken together, the present study provided novel insights into the combined toxicity of MPs and Pb co-exposure on the aorta.

Assessing microbiological and heavy metal pollution in surface waters associated with potential human health risk assessment at fish ingestion exposure

Fish represent a significant source of nutrients but also cause negative health effects due to their bioaccumulation capacity for pollutants. The aim of this study was to examine the transfer of metals from the water of several rivers (Somes, Tisa, Sasar, Lapus, Lăpusel) to fish (Caras sp) tissue (subcutaneous fat, muscles, liver, intestines, kidneys, gills, brain, and eyes) and to identify and assess the carcinogenic and non-carcinogenic health risks of Arsenic (As), Cadmium (Cd), Nickel (Ni), Manganese (Mn), Cooper (Cu), Lead (Pb), Chromium (Cr) and Zinc (Zn) through the ingestion of fish (muscles and subcutaneous fat tissues). The obtained results indicated that a diet consisting of fish is particularly vulnerable, particularly in children compared to adults. The risk assessment results were below the threshold limit, although the fish samples contained heavy metals, with values exceeding the permitted limits of Fe (4.41-1604 mg/kg), Cr (727-4155 µg/kg), Zn (4.72-147 mg/kg), and Ni (333-2194 µg/kg). The studied surface waters are characterized by low and high degrees of pollution with heavy metals, as indicated by the heavy metal pollution index scores (HPI: 12.4-86.4) and the heavy metal evaluation index scores (HEI: 1.06-17.6). The considerable pollution levels are attributed to the high Mn content (0.61-49.7 µg/kg), which exceeded the limit up to fifty times. A consistent set of physico-chemical analysis (pH, electrical conductivity, total hardness, turbidity, chloride, sulphate, nitrate, nitrite, ammonium, Ca, Mg, Na, K) was analysed in water samples as well. Considering the water quality index scores (WQI: 16.0-25.2), the surface waters exhibited good quality. Microbiological results indicated the presence of Listeria monocytogenes and atypical colonies of coagulase-positive staphylococcus in fish. In contrast, the surface waters from which fish samples were collected were positive for Escherichia coli, and coliform bacteria intestinal Enterococci. Based on the study's results, it is recommended to exercise caution in the case of children related to the consumption of fish and using the waters for drinking purposes. This study provides important data of considerable novelty to the riparian population, researchers, and even policy makers on the quality status and potential levels of contamination of river waters, fish and the bioaccumulation of heavy metals in fish that may cause adverse effects on human health if consumed, and similarly the heavy metal pollution degree of waters and the non-carcinogenic risk of heavy metals through ingestion and skin absorption of water in children and adults (the study area is a significant source of fisheries).

Research Progress on Micro (Nano)Plastics Exposure-Induced miRNA-Mediated Biotoxicity

Micro- and nano-plastics (MNPs) are ubiquitously distributed in the environment, infiltrate organisms through multiple pathways, and accumulate, thus posing potential threats to human health. MNP exposure elicits changes in microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), thereby precipitating immune, neurological, and other toxic effects. The investigation of MNP exposure and its effect on miRNA expression has garnered increasing attention. Following MNP exposure, circRNAs serve as miRNA sponges by modulating gene expression, while lncRNAs function as competing endogenous RNAs (ceRNAs) by fine-tuning target gene expression and consequently impacting protein translation and physiological processes in cells. Dysregulated miRNA expression mediates mitochondrial dysfunction, inflammation, and oxidative stress, thereby increasing the risk of neurodegenerative diseases, cardiovascular diseases, and cancer. This tract, blood, urine, feces, placenta, and review delves into the biotoxicity arising from dysregulated miRNA expression due to MNP exposure and addresses the challenges encountered in this field. This study provides novel insights into the connections between MNPs and disease risk.

Green tea polyphenols inhibit TBBPA-induced lung injury via enhancing antioxidant capacity and modulating the NF-κB pathway in mice

Tetrabromobisphenol A (TBBPA) is a global pollutant. When TBBPA is absorbed by the body through various routes, it can have a wide range of harmful effects on the body. Green tea polyphenols (GTPs) can act as antioxidants, resisting the toxic effects of TBBPA on animals. The effects and mechanisms of GTP and TBBPA on oxidative stress, inflammation and apoptosis in the mouse lung are unknown. Therefore, we established in vivo and in vitro models of TBBPA exposure and GTP antagonism using C57 mice and A549 cells and examined the expression of factors related to oxidative stress, autophagy, inflammation and apoptosis. The results of the study showed that the increase in reactive oxygen species (ROS) levels after TBBPA exposure decreased the expression of autophagy-related factors Beclin1, LC3-II, ATG3, ATG5, ATG7 and ATG12 and increased the expression of p62; oxidative stress inhibits autophagy levels. The increased expression of the pro-inflammatory factors IL-1β, IL-6 and TNF-α decreased the expression of the anti-inflammatory factor IL-10 and activation of the NF-κB p65/TNF-α pathway. The increased expression of Bax, caspase-3, caspase-7 and caspase-9 and the decreased expression of Bcl-2 activate apoptosis-related pathways. The addition of GTP attenuated oxidative stress levels, restored autophagy inhibition and reduced the inflammation and apoptosis levels. Our results suggest that GTP can attenuate the toxic effects of TBBPA by modulating ROS, reducing oxidative stress levels, increasing autophagy and attenuating inflammation and apoptosis in mouse lung and A549 cells. These results provide fundamental information for exploring the antioxidant mechanism of GTP and further for studying the toxic effects of TBBPA.

High-fat diet disrupts the gut microbiome, leading to inflammation, damage to tight junctions, and apoptosis and necrosis in Nyctereutes procyonoides intestines

Given the burgeoning Nyctereutes procyonoides breeding industry and its growing scale, it is imperative to investigate the impact of high-fat diets on the health of these animals. This study involved 30 male Nyctereutes procyonoides of comparable weights (3 kg ±0.5), randomly assigned to either a control group or a high-fat diet group (n = 15 each). The latter group was fed a mixture of lard and basal diet in a 2:5 ratio, establishing a high-fat diet model in Nyctereutes procyonoides. This diet induced diarrhea and histopathological changes in the Nyctereutes procyonoides. Analysis of the small intestine contents using 16S rRNA sequencing revealed a high-fat diet-induced disruption in the gut microbiota. Specifically, Escherichia-Shigella emerged as the biomarker in the high-fat diet group (P = 0.049), while Vagococcus was prevalent in the control group (P = 0.049), indicating a significant increase in harmful bacteria in the high-fat diet group. Furthermore, this disrupted gut flora correlated with inflammation and oxidative stress, as evidenced by marked increases in TNF-α (P < 0.01), IL-1β (P < 0.05), and IL-6 (P < 0.05) levels, measured via q-PCR, Western blot, and oxidative stress assays. In addition, q-PCR analysis revealed significant upregulation of apoptosis and necrosis markers, including Bax, Caspase3, Caspase9, Caspase12, RIPK3, and RIPK1 (P < 0.01 to P < 0.001), and a concurrent downregulation of the anti-apoptotic gene Bcl-2 (P < 0.01) in the high-fat diet group, consistent with protein expression trends. These findings suggest that a high-fat diet alters the gut microbiome toward a more harmful bacterial composition, escalating inflammatory responses and intestinal tissue permeability, culminating in intestinal cell apoptosis and necrosis.IMPORTANCEThis study examines the impact of high-fat diets on Nyctereutes procyonoides. Our research established a Nyctereutes procyonoides model on a high-fat diet, revealing significant health impacts, such as diarrhea, histological anomalies, and alterations in the gut microbiota. These findings emphasize the importance of preventing health issues and promoting sustainable industry growth. They highlight the significant impact of diet on gut microbiota and overall animal health.

Microplastics induced endoplasmic reticulum stress to format an inflammation and cell death in hepatocytes of carp (Cyprinus carpio)

Microplastics (MPs) are a serious threat to the living environment of aquatic organisms. However, there are fewer studies on the toxicity of microplastics to freshwater organisms. This study aimed to establish a polystyrene microplastics (PS-MPs) model by feeding carp (Cyprinus carpio) PS-MP (1000 ng/L) particles 8 μm in size. HE staining revealed a mass of inflammatory cells infiltrated in the carp hepatopancreas. The activities of alkaline phosphatase (AKP), aspartate transaminase (AST), lactate dehydrogenase (LDH), and alanine transaminase (ALT) were strengthened considerably, suggesting that PS-MPs cause injury to the hepatopancreas of carp. Real-Time polymerase chain reaction and western blotting results indicated increased levels of glucose-regulated protein 78 (GRP78), (PKR)-like ER kinase (PERK), eukaryotic translation initiation Factor 2α (EIF2α) and activating transcription Factor 4 (ATF4) genes and increased levels of inflammatory factors downstream of endoplasmic reticulum stress (ERs) thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), interleukin-18 (IL-18), interleukin-1β (IL-1β), and caspase 1. Increased expression of microtubule-associated protein-2 (LC3II), autophagy-related 5 (ATG5) and autophagy-related 12 (ATG12) genes revealed that PS-MPs promoted autophagy in carp hepatocytes. The enhanced expression of the Caspase 12, Caspase 3, and Bax genes suggested that PS-MPs led to the apoptosis of carp hepatocytes. These results suggest that PS-MPs result in serious injury to the hepatopancreas of carp. The present study of PS-MPs in freshwater fish from the aspect of endoplasmic reticulum stress was conducted to provide references and suggestions for toxicological studies of PS-MPs in freshwater environments.

Polyethylene microplastics induced gut microbiota dysbiosis leading to liver injury via the TLR2/NF-κB/NLRP3 pathway in mice

Microplastics (MPs) are ubiquitous environmental contaminants that have negative impacts on health and safety. The gut microbiota plays multiple roles as a newly discovered virtual metabolic organ. The objective of this study was to investigate the potential of MPs to cause liver injury by disrupting the balance of gut microbiota. The results indicated that exposure to MPs resulted in liver damage and disrupted the homeostasis of gut microbiota. MPs significantly reduced the liver organ coefficient, leading to liver cell injury and impaired function. Additionally, there was an increase in the expression of fibril-related proteins, which positively correlated with MPs concentration. Furthermore, MPs increased the relative abundances of Desulfovibrio, Clostridia, Enterorhabdus, Bacteroides, and Gemella while decreasing the abundance of Dubosoella. Different concentrations of MPs exhibited varying effects on specific bacterial groups, however, both concentrations resulted in an increase in pathogenic bacteria and a decrease in beneficial bacteria, as well as alterations in microbial structure. Moreover, MPs induced oxidative stress, inflammation, apoptosis and necrosis in liver cells. The study found that MPs disrupted gut microbiota homeostasis and activated TLR2/NF-κB/NLRP3 pathway in the liver, providing a new insight into the mechanism underlying MPs-induced liver injury. These findings serve as a warning regarding environmental pollution caused by MPs.

Tea polyphenols alleviate TBBPA-induced inflammation, ferroptosis and apoptosis via TLR4/NF-κB pathway in carp gills

The extensive application of Tetrabromobisphenol A (TBBPA) leads to the pollution of part of the water environment and brings great safety risks to aquatic animals. As a natural extract, tea polyphenols (TPs) have antioxidant and anti-inflammatory effects. Gills are one of the immune organs of fish and constitute the first line of defense of the immune system. However, it was unclear whether TPs could mitigate TBBPA-induced gills injury. Therefore, an animal model was established to investigate the effect of TPs on TBBPA-induced gills. The results indicated that TBBPA changed the coefficient and tissue morphology of carp gills. In addition, TBBPA induced oxidative stress and inflammation, leading to ferroptosis and apoptosis in carp gills. Dietary addition of TPs significantly improved the antioxidant capacity of carp, effectively inhibited the overexpression of TLR4/NF-κB and its mediated inflammatory response. Moreover, TPs restored iron metabolism, reduced the expression of pro-apoptotic factors thereby alleviating ferroptosis and apoptosis in carp gills. This study enriched the protective effect of TPs and provided a new way to improve the innate immunity of carp.

Polyethylene microplastics induced inflammation via the miR-21/IRAK4/NF-κB axis resulting to endoplasmic reticulum stress and apoptosis in muscle of carp

As a widespread environmental pollutant, microplastics pose a great threat to the tissues and organs of aquatic animals. The carp's muscles are necessary for movement and survival. However, the mechanism of injury of polyethylene microplastics (PE-MPs) to carp muscle remains unclear. Therefore, in this study, PE-MPs with the diameter of 8 μm and the concentration of 1000 ng/L were used to feed carp for 21 days, and polyethylene microplastic treatment groups was established. The results showed that PE-MPs could cause structural abnormalities and disarrangement of muscle fibers, and aggravate oxidative stress in muscles. Exposure to PE-MPs reduced microRNA (miR-21) in muscle tissue, negatively regulated Interleukin-1 Receptor Associated Kinase 4 (IRAK4), activated Nuclear Factor Kappa-B (NF-κB) pathway, induced inflammation, and led to endoplasmic reticulum stress and apoptosis. The present study provides different targets for the prevention of muscle injury induced by polyethylene microplastics.