The antagonistic effect of selenium on cadmium-induced apoptosis via PPAR-γ/PI3K/Akt pathway in chicken pancreas

Sex hormone binding globulin (SHBG) modulates mitochondrial dynamics in PPARγ-depleted equine adipose derived stromal cells

Peroxisome proliferator-activated receptor gamma (PPARγ) is a transcription factor that promotes adipogenesis, lipid uptake and storage, insulin sensitivity, and glucose metabolism. Hence, defects in PPARγ have been associated to the development of metabolic disorders. Sex hormone-binding globulin (SHBG) is a glycoprotein primarily produced in the liver that regulates the bioavailability of sex hormones. Alike PPARγ, low SHBG levels have been correlated with insulin resistance and associated endocrine abnormalities. Therefore, this study aimed to verify whether SHBG may restore depleted PPARγ functions and thus serve as a new candidate for the management of metabolic conditions. A model of equine adipose-derived stromal cells (EqASCs) has been used, in which a PPARγ silencing and SHBG treatment have been achieved to determine the changes in cell viability, premature senescence, oxidative stress, and mitochondrial functions. Obtained data demonstrated that loss in PPARγ triggers cell apoptosis which is not reversed by SHBG application. Moreover, PPARγ knockdown cells exhibited premature senescence, which has been substantially alleviated by SHBG concomitantly to increased BAX/BCL2 ratio, suggesting a possible effect on senescence-induced apoptosis resistance. Interestingly, PPARγ silencing induced a significant alteration in mitochondrial membrane potential as well as the expression of dynamics and metabolism-related markers. SHBG treatment enabled to ameliorate the transmembrane potential, to normalize the expression levels of key dynamics and metabolism mediators, and to restore the protein levels of PINK, which is critically involved in mitochondria recycling machinery. Presented data suggest that SHBG may provide new mechanistic insights into the regulation of PPARγ functions, and thus offers a preliminary picture on a possible SHBG-PPARγ metabolic crosstalk. KEY MESSAGES : PPARγ is a transcription factor that tightly regulates cell metabolism. Low SHBG levels correlate with insulin resistance and associated endocrine abnormalities. PPARγ silencing reduces cell viability, triggers premature senescence and profound mitochondrial failure in equine ASCs. SHBG protein reverses senescent phenotype and apoptosis resistance of PPARγ- ASCs. SHBG improves mitochondrial dynamics and metabolism following PPARγ knockdown. SHBG might serve as a PPARγ potential mimicking agent for the modulation of ASCs metabolic processes.

Chronic lead poisoning-induced budgerigar liver damage, gut microbiota dysbiosis, and metabolic disorder

Birds are sensitive to heavy metal pollution, and lead (Pb) contamination can negatively affect their liver and gut. Therefore, we used budgerigars to examine liver and gut toxicosis caused by Pb exposure in bird, and the possible toxic mechanisms. The findings showed Pb exposure increased liver weight and decreased body weight. Moreover, histopathological and immunofluorescence assay results demonstrated obvious liver damage and cell apoptosis increased in Pb- treated budgerigars. Quantitative polymerase chain reaction (qPCR) results also showed Pb caused an increase in apoptosis by inhibiting the PPAR-γ/PI3K/Akt pathway. The gut microbe analyses indicated Firmicutes, Proteobacteria, and Bacteroidetes were dominant microbial phyla, and Network analysis results shown Arthrobacter, Bradyrhizobium and Alloprevotella as the hubs of Modules I, II, and III, respectively. Phenylpropanoids and polyketides, Organoheterocyclic compounds, Organic oxygen compounds, and Organic nitrogen compounds were dominant metabolite superclasses. Tauroursodeoxycholic acid, taurochenodeoxycholic acid (sodium salt), and 2-[2-(5-bromo-2-pyridyl)diaz-1-enyl]-5-(diethylamino)phenol were significantly enriched in the Pb-treated group. It showed that 41 Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologues and 183 pathways differed between the Pb-treated and control budgerigars using microbial and metabolomic data. Moreover, orthogonal partial least-squares discrimination analysis (OPLS-DA) based on microbial and metabolite indicated distinct clusters in the Pb-treated and control groups. Additionally, the correlation analysis results indicated that a positive correlation for the Pb-treated and control groups between gut microbiota and metabolomic data, respectively. Furthermore, the microenvironment of the gut and liver were found to affect each other, and this study demonstrated heavy metal especially Pb may pose serious health risks to birds through the "gut-liver axis" too.

Exposure to the environmental pollutant chlorpyrifos induces hepatic toxicity through activation of the JAK/STAT and MAPK pathways

Chlorpyrifos (CHP) is an inexpensive highly effective organophosphate insecticide used worldwide. The unguided and excessive use of CHP by farmers has led to its significant accumulation in crops as well as contamination of water sources, causing health problems for humans and animals. Therefore, this study evaluated the toxicological effects of exposure to the environmental pollutant CHP at low, medium, and high (2.5, 5, and 10 mg·kg-1 BW) levels on rat liver by examining antioxidant levels, inflammation, and apoptosis based on the no observed adverse effect levels (NOAEL) (1 mg·kg-1 BW) and the CHP dose that does not cause any visual symptoms (5 mg·kg-1 BW). Furthermore, the involvement of the JAK/STAT and MAPK pathways in CHP-induced toxic effects was identified. The relationship between the expression levels of key proteins (p-JAK/JAK, p-STAT/STAT, p-JNK/JNK, p-P38/P38, and p-ERK/ERK) in the pathways and changes in the expression of markers associated with inflammation [inflammatory factors (IL-1β, IL-6, IL-10, TNF-α), chemokines (GCLC and GCLM), and inflammatory signaling pathways (NF-кB, TLR2, TLR4, NLRP3, ASC, MyD88, IFN-γ, and iNOS)] and apoptosis [Bad, Bax, Bcl-2, Caspase3, Caspase9, and the cleavage substrate of Caspase PARP1] were also determined. The results suggest that CHP exposure disrupts liver function and activates the JAK/STAT and MAPK pathways via oxidative stress, exacerbating inflammation and apoptosis. Meanwhile, the JAK/STAT and MAPK pathways are involved in CHP-induced hepatotoxicity. These findings provide a novel direction for effective prevention and amelioration of health problems caused by CHP abuse in agriculture and households.

Myeloid Trem2 ameliorates the progression of metabolic dysfunction-associated steatotic liver disease by regulating macrophage pyroptosis and inflammation resolution

BACKGROUND

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing year by year and has become one of the leading causes of end-stage liver disease worldwide. Triggering Receptor Expressed on Myeloid Cells 2 (Trem2) has been confirmed to play an essential role in the progression of MASLD, but its specific mechanism still needs to be clarified. This study aims to explore the role and mechanism of Trem2 in MASLD.

METHODS

Human liver tissues were obtained from patients with MASLD and controls. Myeloid-specific knockout mice (Trem2mKO) and myeloid-specific overexpression mice (Trem2TdT) were fed a high-fat diet, either AMLN or CDAHFD, to establish the MASLD model. Relevant signaling molecules were assessed through lipidomics and RNA-seq analyses after that.

RESULTS

Trem2 is upregulated in human MASLD/MASH-associated macrophages and is associated with hepatic steatosis and inflammation progression. Hepatic steatosis and inflammatory responses are exacerbated with the knockout of myeloid Trem2 in MASLD mice, while mice overexpressing Trem2 exhibit the opposite phenomenon. Mechanistically, Trem2mKO can aggravate macrophage pyroptosis through the PI3K/AKT signaling pathway and amplify the resulting inflammatory response. At the same time, Trem2 promotes the inflammation resolution phenotype transformation of macrophages through TGFβ1, thereby promoting tissue repair.

CONCLUSIONS

Myeloid Trem2 ameliorates the progression of Metabolic dysfunction-associated steatotic liver disease by regulating macrophage pyroptosis and inflammation resolution. We believe targeting myeloid Trem2 could represent a potential avenue for treating MASLD.

The antagonism mechanism of astilbin against cadmium-induced injury in chicken lungs via Treg/Th1 balance signaling pathway

The purpose of this study was to investigate the effect of Treg/Th1 imbalance in cadmium-induced lung injury and the potential protective effect of astilbin against cadmium-induced lung injury in chicken. Cadmium exposure significantly decreased T-AOC and GSH-Px levels and SOD activity in the chicken lung tissues. In contrast, it significantly increased the MDA and NO levels. These results indicate that cadmium triggers oxidative stress in lungs. Histopathological analysis revealed that cadmium exposure further induced infiltration of lymphocytes in the chicken lungs, indicating that cadmium causes pulmonary damage. Further analysis revealed that cadmium decreased the expression of IL-4 and IL-10 but increased those of IL-17, Foxp3, TNF-α, and TGF-β, indicating that the exposure of cadmium induced the imbalance of Treg/Th1. Moreover, cadmium adversely affected chicken lung function by activating the NF-kB pathway and inducing expression of genes downstream to these pathways (COX-2, iNOS), associated with inflammatory injury in the lung tissue. Astilbin reduced cadmium-induced oxidative stress and inflammation in the lungs by increasing antioxidant enzyme activities and restoring Treg/Th1 balance. In conclusion, our results suggest that astilbin treatment alleviated the effects of cadmium-mediated lung injury in chickens by restoring the Treg/Th1 balance.

Selenium prevented renal tissue damage in lipopolysaccharide-treated rats

OBJECTIVES

Kidney diseases are one of the common diseases, which are one of the main causes of death in society and impose costs on the health system of the society. A growing body of evidence has well documented that inflammatory responses and oxidative damage play a significant role in the progress of various kidney diseases.

METHODS

This study examined whether selenium (Sel) could prevent the detrimental influences of lipopolysaccharide (LPS) in rats. Four groups of Wistar rats were considered: control, LPS (1 mg/kg, i.p., for 14 days), LPS-Sel 1 (0.1 mg/kg, i.p., for 14 days), and LPS-Sel 2 (0.2 mg/kg, i.p., for 14 days).

RESULTS

Sel treatment markedly attenuated oxidative stress damage in the kidney tissue in LPS-induced renal toxicity. Generally, the administration of Sel resulted in improved antioxidant indicators such as catalase (CAT) and superoxide dismutase (SOD) activities, or total thiol content, and decreased malondialdehyde (MDA) in the kidney tissue. It also decreased interleukin-6 in kidney homogenates. Furthermore, Se treatment significantly inhibited the elevation of serum biochemical markers of kidney function including serum, BUN, and creatinine.

CONCLUSIONS

Based on the findings of the current study, it seems that the administration of Sel to LPS-treated rats improves renal function by reducing oxidative damage and inflammation in kidney tissue. However, more research is needed to reveal the accurate mechanisms for the effect of Sel on renal outcomes of LPS in human subjects.

BPA and low-Se exacerbate apoptosis and mitophagy in chicken pancreatic cells by regulating the PTEN/PI3K/AKT/mTOR pathway

INTRODUCTION

Bisphenol A (BPA) is a widespread environmental pollutant which has serious toxic effects on organisms. One of the crucial trace elements is selenium (Se), whose shortage can harm biological tissues and enhance the toxicity of contaminants, in which apoptosis and autophagy are core events.

OBJECTIVES

An in vivo model was established to investigate the effects of BPA and low-Se on chicken pancreatic tissue, and identify the possible potential molecular mechanism.

METHODS

A total of 80 1-day-old broiler chickens (Xinghua Chicken Farm, Harbin, China) were stochastically divided into 4 groups (n = 20/group): Control group, BPA group, low-Se group, and low-Se + BPA group. Pancreatic tissue was collected at day 42 to detect changes in markers.

RESULTS

First, the data showed that BPA and low-Se exposure gave rose to structural abnormalities in pancreatic tissue, oxidative stress, mitochondrial dysfunction and homeostasis imbalance, apoptosis and mitophagy. In addition, the co-exposure of BPA and low-Se caused the most serious damage to pancreatic tissue. In terms of mechanism, it was found that apoptosis and mitophagy induced by BPA and low-Se were related to the activation of PTEN/PI3K/AKT/mTOR pathway.

CONCLUSION

In summary, the study found that BPA and low-Se exacerbated mitochondria damage, apoptosis and mitophagy by regulating the PTEN/PI3K/AKT/mTOR pathway.

Selenium attenuated food borne cadmium-induced intestinal inflammation in red swamp crayfish (Procambarus clarkii) via regulating PI3K/Akt/NF-κB pathway

Selenium (Se), an indispensable micronutrient for living organisms, has been extensively studied for its heavy metal-detoxifying properties in diverse biological systems and tissues. Nevertheless, it is not entirely certain whether Se can effectively protect against Cadmium (Cd)-induced gut inflammation, especially in aquatic animals. In this study, we employed various approaches, including transcriptome profiling, histological examinations, assessment of antioxidant enzyme activities, and analysis of gut microbiota composition to investigate the effects on crayfish growth and intestinal health after exposure to dietary Cd (15 mg kg-1 diet) and Se (15 mg kg-1 diet) individually or in combination for 8 weeks. The results revealed that dietary Cd exposure resulted in reduced body weight and survival rates, along with an increased occurrence of intestinal inflammation. Nevertheless, Se supplementation proved effective in mitigating the adverse effects of Cd on growth and gut health. Se exhibited a remarkable ability to counteract the disruption of gut antioxidant abilities induced by dietary Cd, as evidenced by the observed increases in ROS and MDA contents, decrease in GSH levels, and inhibition of antioxidative enzyme activities. At the concentration of 6 mg kg-1 in the diet, Se was found beneficial for maintaining gut microbiota richness and diversity. Among them, Flavobacterium, Thermomonas, and Chloronema displayed a weak negative correlation with the rate of gut inflammation. Meanwhile, the levels of short chain fatty acids (SCFAs), including acetic acid (AA) and butanoic acid (BA), showed a significant increase in the Se-Cd group compared to the Cd-only group. Furthermore, transcriptome analysis exhibited significant responses of the PI3K/Akt and NF-κB pathways following crayfish exposure to dietary Se and Cd, either separately or in combination. In short, this study provides a new evidence regarding the molecular mechanisms through which Se could regulate the PI3K/Akt and NF-κB pathways, either directly or indirectly via ROS and SCFAs, thereby alleviating Cd-induced gut inflammation in crayfish.

Palliative Effect of Combined Application of Zinc and Selenium on Reproductive Injury Induced by Tripterygium Glycosides in Male Rats

The long-term use of tripterygium glycosides (TG) can lead to male reproductive damage. Research indicates that zinc and selenium exhibit a synergistic effect in the male reproductive system, with the combined preparation demonstrating superior therapeutic effects compared to individual preparations. The purpose of this study was to explore the specific mechanism by which zinc and selenium mitigate reproductive toxicity induced by TG in male rats. Rats were randomly assigned to three groups: control group (C group), model group (M group, receiving TG at 30 mg/kg/day), and model + zinc + selenium group (ZS group). The ZS group was also given TG gavage for the first 4 weeks. Starting from the fifth week until the conclusion of the eighth week, the ZS group received an additional protective treatment of 10 mg/kg/day Zn and 0.1 mg/kg/day Se 4 h after TG administration. Following euthanasia, blood samples, rat testis, and epididymis tissues were collected for further experiments. Combined zinc-selenium treatment corrects the imbalance of zinc-selenium homeostasis in testicular tissue induced by TG. This is achieved by upregulating the expression of metal transcription factor (MTF1) and zinc transporters ZIP8 and ZIP14 and downregulating the expression of ZnT10. Improvement of zinc and selenium homeostasis enhanced the expression of zinc-containing enzymes (ADH, LDH, and ALP) and selenoproteins (GPx1 and SELENOP) in the testis. At the same time, zinc and selenium mitigate TG-induced reproductive damage by promoting the activity of antioxidant enzymes and upregulating the expression of proteins associated with the oxidative stress pathway, including Nrf2, Keap1, HO-1, PI3K, and p-AKT.

Cadmium as an ovarian toxicant: A review

Cadmium (Cd) is a ubiquitous heavy metal toxicant with no biological function in the human body. Considerably, because of its long biological half-life and very low excretion rate, Cd is inclined to accumulate and cause deleterious effects on various body organs (e.g., liver, kidney, and ovary) in humans and animals. Ovaries are the most vulnerable targets of Cd toxicity. Cd has been shown to induce oxidative stress, follicular atresia, hormonal imbalance, and impairment of oocyte growth and development. Moreover, Cd toxicity has been associated with increasing incidences of menstrual disorders, pregnancy loss, preterm births, delayed puberty, and female infertility. Therefore, it is crucial to understand how Cd poisoning impacts specific ovarian processes for the development of preventive interventions to enhance female fertility. The current review attempts to collate the recent findings on Cd-induced oxidative stress, follicular apoptosis, steroid synthesis inhibition, and teratogenic toxicity, along with their possible mechanisms in the ovarian tissue of different animal species. Additionally, the review also summarizes the studies related to the use of many antioxidants, medicinal herbs, and other compounds as remedial approaches for managing Cd-induced ovarian toxicity.

A study on the effectiveness of sodium selenite in treating cadmium and perfluoro octane sulfonic (PFOS) poisoned zebrafish (Danio rerio)

Perfluoro octane sulfonate (PFOS) and cadmium (Cd) are toxic elements in the environment. As a micronutrient trace element, selenium (Se) can mitigate the adverse effects induced by PFOS and Cd. However, few studies have examined the correlation between Se, PFOS and Cd in fish. The present study focused on the antagonistic effects of Se on PFOS+Cd-induced accumulation in the liver of zebrafish. The fish was exposed to PFOS (0.08mg/L), Cd (1mg/L), PFOS+ Cd (0.08 mg/L PFOS+1 mg/L Cd), L-Se (0.07mg/L Sodium selenite +0.08mg/L PFOS+1mg/L Cd), M-Se (0.35mg/L Sodium selenite + 0.08mg/L PFOS+ 1 mg/L Cd), H-Se (1.75 mg/L Sodium selenite + 0.08 mg/L PFOS+ 1mg/L Cd) for 14d. The addition of selenium to fish exposed to PFOS and Cd has been found to have significant positive effects. Specifically, selenium treatments can alleviate the adverse effects of PFOS and Cd on fish growth, with a 23.10% improvement observed with the addition of T6 compared to T4. In addition, selenium can alleviate the negative effects of PFOS and Cd on antioxidant enzymes in zebrafish liver, thus reducing the liver toxicity caused by PFOS and Cd. Overall, the supplementation of selenium can reduce the health risks to fish and mitigate the injuries caused by PFOS and Cd in zebrafish.

Nano-selenium Antagonizes Heat Stress-Induced Apoptosis of Rainbow Trout (Oncorhynchus mykiss) Hepatocytes by Activating the PI3K/AKT Pathway

The cold-water fish rainbow trout (Oncorhynchus mykiss) shows poor resistance to heat, which is the main factor restricting their survival and yield. With the advancement of nanotechnology, nano-selenium (nano-Se) has emerged as a key nano-trace element, showing unique advantages, including high biological activity and low toxicity, for studying the response of animals to adverse environmental conditions. However, little is still known regarding the potential protective mechanisms of nano-Se against heat stress-induced cellular damage. Herein, we aimed to investigate the mechanism underlying the antagonistic effects of nano-Se on heat stress. Four groups were assessed: CG18 (0 μg/mL nano-Se, 18 °C), Se18 (5.0 μg/mL nano-Se, 18 °C), CG24 (0 μg/mL nano-Se, incubated at 18 °C for 24 h and then transferred to 24 °C culture), and Se24 (5.0 μg/mL nano-Se, incubated at 18 °C for 24 h and then transferred to 24 °C culture). We found that after heat treatment (CG24 group), T-AOC, GPx, and CAT activities in rainbow trout hepatocytes showed a decrease of 36%, 33%, and 19%, respectively, while ROS and MDA levels showed an increase of 67% and 93%, respectively (P < 0.05). Meanwhile, the mRNA levels of the apoptosis-related genes caspase3, caspase9, Cyt-c, Bax, and Bax/Bcl-2 in the CG24 group were 41%, 47%, 285%, 65%, and 151% higher than those in the CG18 group, respectively, while those of PI3K and AKT were 31% and 17% lower, respectively (P < 0.05). Besides, flow cytometry analysis showed an increase in the level of apoptotic cells after heat exposure. More importantly, we observed that nano-Se cotreatment (Se24 group) remarkably attenuated heat stress-induced effects (P < 0.05). We conclude that heat stress induces oxidative stress and apoptosis in rainbow trout hepatocytes. Nano-Se ameliorates heat stress-induced apoptosis by activating the PI3K/AKT pathway. Our results provide a new perspective to improve our understanding of the ability of nano-Se to confer heat stress resistance.

Wild Rosa roxburghii Tratt Juices Grown at Different Altitudes Regulate Blood Glucose in Type 1 Diabetic Mice via the PI3K/Akt Pathway

To explore hypoglycemic effect of wild Rosa roxburghii tratt (RRT) juice at different altitudes on type 1 diabetes mellitus (T1DM). The T1DM mouse model was induced by streptozotocin (STZ), and the experiment included a normal group (NC), model group (MC), wild RRT juice groups high (HF), medium (MF), low altitude (DF) and cultivated control group (PC). During experiment, food intake, water intake, body weight, and fasting blood glucose were measured. After 28 days of administration, glucose tolerance, glycogen level, lipid profiles, and antioxidation levels in serum and liver were measured, and histomorphological changes of liver and kidney were observed by hematoxylin and eosin staining. The results showed that wild RRT juice reduced blood glucose level, alleviated liver and kidney tissue damage, improved glucose and lipid metabolism disorders and attenuated oxidative damage in T1DM mice. Western blot showed that wild RRT juice at grown at different altitudes significantly increased protein abundance of PI3K, Akt, and GLUT2 in liver of T1DM mice. In conclusion, wild RRT juice from different altitudes improved glucose and lipid metabolism disorders and oxidative damage in T1DM mice, which may be attributed to activation of PI3K/Akt pathway. Overall effect: MF > PC > HF > DF.

Chronic Exposure to Environmental Pollutant Ammonia Causes Damage to the Olfactory System and Behavioral Abnormalities in Mice

Ammonia (NH3) is a major air pollutant. However, few studies have been extended beyond the histopathological changes in the olfactory mucosa to the impact of NH3 exposure on other parts of the olfactory system and olfactory functioning. Therefore, we assessed the effects of exogenous NH3 (either 20 ppm for the low exposure group or 200 ppm for the high exposure group) on the various parts of the olfactory system by histological observation, gene expression, immunochemistry, and chemical analyses. A total of 140 Institute of Cancer Research mice (4 weeks old), 70 females and 70 males (average body weight at the start: 21.5 ± 1.9 g), were used. The exposure lasted for 4 weeks, and the mice were exposed to the NH3 for 4 h per day. Our results showed that chronic exposure to NH3 damaged the olfactory system, with consequences for changing the foraging behavior and anxiety behavior. Our results also suggest that it is plausible that NH3 recruited T cells and activated microglia cells and astrocytes, leading to inflammation in the olfactory system. Increased release of proinflammatory cytokines (TNF-α, IL-1β, IL-6, and interferon-γ) and reduced release of anti-inflammatory cytokines (IL-4 and IFN-beta) led to tissue damage and compromised the functions of the olfactory system.

Phthalates (PAEs) and reproductive toxicity: Hypothalamic-pituitary-gonadal (HPG) axis aspects

Phthalates (PAEs) are widely used for their excellent ability to improve plastic products. As an essential endocrine axis that regulates the reproductive system, whether dysfunction of the hypothalamic-pituitary-gonadal (HPG) axis is involved in reproductive toxicity mediated by environmental endocrine disruptors PAEs has become a hot topic of widespread concern. This study systematically reviewed the adverse effects of multiple PAEs on the HPG axis in different models and objectively discussed the possible underlying mechanisms. The abnormal release of gonadotropin-releasing hormone and gonadotropin, dysfunction of sex hormone receptors and steroid hormone synthesis, and general damage, including cell proliferation, oxidative stress, apoptosis, and autophagy have been confirmed to be involved in this process. Although it is widely established that PAEs induce HPG axis dysfunction, the specific mechanisms involved remain unclear. From a systematic review of relevant publications, it appears that the abnormal expression of peroxisome proliferator-activated, aryl hydrocarbon, and insulin receptors mediated by PAEs is key upstream event that induces these adverse outcomes; however, this inference needs to be further verified. Overall, this study aimed to provide reliable potential biomarkers for future environmental risk assessment and epidemiological investigation of PAEs.

Zinc alleviates cadmium-induced reproductive toxicity via regulating ion homeostasis, metallothionein expression, and inhibiting mitochondria-mediated apoptosis in the freshwater crab Sinopotamon henanense

Cadmium (Cd) is a carcinogenic environmental pollutant that harms male reproductive systems by lowering sperm quality, impairing spermatogenesis, and causing apoptosis. Although zinc (Zn) has been reported to alleviate Cd toxicity, the underlying mechanisms have not been fully elucidated. The aim of this work was to investigate the mitigating effects of Zn on Cd-induced male reproductive toxicity in the freshwater crab Sinopotamon henanense. Cd exposure not only resulted in its accumulation but also in Zn deficiency, decreased sperm survival rate, poor sperm quality, altered ultrastructure, and increased apoptosis in the testis of the crabs. Morever, Cd exposure increased the expression and distribution of metallothionein (MT) in the testis. However, Zn supplementation effectively mitigated the aforementioned effects of Cd, as demonstrated by preventing Cd accumulation, increasing Zn bioavailability, alleviating apoptosis, increasing mitochondrial membrane potential, decreasing reactive oxygen species (ROS) levels, and restoring MT distribution. Moreover, Zn also significantly reduced the expression of apoptosis-related (p53, Bax, CytC, Apaf-1, Caspase-9, Caspase-3), metal transporter-related ZnT1, metal-responsive transcription factor 1 (MTF1), and the gene and protein expression of MT, while increasing the expression of ZIP1 and Bcl-2 in the testis of Cd-treated crabs. In conclusion, Zn alleviates Cd-induced reproductive toxicity via regulating ion homeostasis, MT expression, and inhibiting mitochondria-mediated apoptosis in the testis of S. henanense. The information obtained in this study may serve as the foundation for further investigation into the development of mitigation strategies for adverse ecological and human health outcomes associated with Cd contamination or poisoning.

The stereoselective toxicity of dinotefuran to Daphnia magna: A systematic assessment from reproduction, behavior, oxidative stress and digestive function

Dinotefuran is a promising neonicotinoid insecticide with chiral structure. In the present study, the stereoselective toxicity of dinotefuran to Daphnia magna (D. magna) was studied. The present result showed that S-dinotefuran inhibited the reproduction of D. magna at 5.0 mg/L. However, both R-dinotefuran and S-dinotefuran had no genotoxicity to D. magna. Additionally, neither R-dinotefuran nor S-dinotefuran had negative influences on the motor behavior of D. magna. However, S-dinotefuran inhibited the feeding behavior of D. magna at 5.0 mg/L. Both R-dinotefuran and S-dinotefuran induced oxidative stress effect in D. magna after exposure. R-dinotefuran significantly activated the activities of superoxide dismutase (SOD) and glutathione S-transferase (GST), while S-dinotefuran showed the opposite effect. S-dinotefuran had more obvious activation effect on the acetylcholinesterase (AchE) activity and trypsin activity compared to R-dinotefuran. The transcriptome sequencing results showed that S-dinotefuran induced more DEGs in D. magna, and affected the normal function of ribosome. The DEGs were mainly related to the synthesis and metabolism of biomacromolecules, indicating the binding mode between dinotefuran enantiomer and biomacromolecules were different. Additionally, the present result indicated that the digestive enzyme activity and digestive gene expression levels in D. magna were greatly enhanced to cope with the inhibition of S-dinotefuran on the feeding.

Selenium as a predictor of metabolic syndrome in middle age women

BACKGROUND

Selenium plays an important role in metabolic homeostasis. It has been suggested that it may also affect the expression and activity of PPAR-γ. The aim of study was to analyze the relationships between these variables in the context of the health of women, for whom the risk of MetS increases with age.

MATERIAL AND METHODS

The study involved 390 women in middle age. The stages of study: a survey-based part; anthropometric measurements; analysis of biological material (blood) in terms of glycemia, triglyceride, HDL, and selenium levels, as well as genetic analysis of the PPAR-γ polymorphisms.

RESULTS

It was found that selenium may moderate the effect of the G allele of the PPAR-γ gene on the occurrence of elevated waist circumference (OR=1.030, 95%CI 1.005-1.057, p=0.020); and the effect of the C (OR=1.077, 95%CI 1.009-1.149, p=0.026) and the G alleles (OR=1.052, 95%CI 1.025-1.080, p<0.000) on the odds of elevated blood pressure. Women in whom HDL levels were not significantly reduced, had higher selenium levels (p=0.007).

CONCLUSIONS

1. The effect of selenium on MetS and its components has not been demonstrated. 2. The effect of individual alleles of the PPAR-γ gene on MetS and its components was not demonstrated. 3. The concentration of selenium may affect waist circumference in carriers of the G allele, and arterial hypertension in carriers of the C and G alleles by affecting the expression of PPAR-γ. 4. Higher selenium concentrations increased the odds of higher HDL levels in the group of subjects meeting the MetS criteria.

Curcumin alleviates ketamine-induced oxidative stress and apoptosis via Nrf2 signaling pathway in rats' cerebral cortex and hippocampus

AIMS

To investigate curcumin's protective effect on nerve damage caused by ketamine anesthesia via the Nrf2 signaling pathway. Rats and PC12 cells were used in this experiment to investigate the mechanism of nerve injury caused by ketamine anesthesia. Furthermore, our findings suggest that curcumin may affect oxidative stress and apoptosis by targeting the Nrf2 pathway, thereby alleviating the nerve injury caused by ketamine.

METHODS

The rat cerebral cortex and hippocampus were stained with Nissl and immunohistochemistry to determine the number of neurons and the expression of Caspase-3, Bcl-2, and Bax. CCK-8 assay was used to determine the optimal concentration of ketamine, curcumin, and H₂ O₂ in PC12 cells. Flow cytometry was used to detect changes in reactive oxygen species and the rate of apoptosis in each group. To determine whether Nrf2 entered the nucleus, immunofluorescence was used. Both tissues and cells were subjected to RT-PCR and Western blotting detection at the same time. The levels of oxidative stress were determined using a malondialdehyde (MDA) and superoxide dismutase (SOD) assay kit.

RESULTS

Ketamine reduced the number of neurons in the cortex and hippocampus of rats. The proteins Bax and Caspase-3 were upregulated, while Bcl-2 was down-regulated in the cortex and hippocampus. The viability of PC12 cells has decreased. MDA content increased while SOD activity decreased in cortex, hippocampus, and PC12 cells. Ketamine had an effect on the expression of some genes in the Nrf2 signaling pathway as well as apoptosis. Curcumin pretreatment may be able to prevent ketamine-induced damage.

CONCLUSIONS

The oxidative stress and apoptosis caused by ketamine during growth of the cerebral cortex, hippocampus, and PC12 cells may be decreased by curcumin's activation of the Nrf2 signaling pathway. Our research provides a potential strategy for the secure administration of anesthetics in medical settings.

Ameliorative effects of dietary selenium against cadmium toxicity on production performance and egg quality in laying hens

In order to reveal the influences of supplemented dietary selenium (Se) on the suppressive effect of cadmium (Cd) toxicity on performance and egg properties of laying hens, the effects of co-treatment Se and Cd on the performance, egg quality, levels of amino acids and the antioxidant capacity of egg and serum were investigated. A total of 128 31-week-old laying hens were randomly distributed in four treatments, which were fed with the basic diet (0.2 mg/kg Se and 0.08 mg/kg Cd), and the basic diet with Se (1.1 mg/kg Se and 0.08 mg/kg Cd), Cd (0.2 mg/kg Se and 92.1 mg/kg Cd) and Se+Cd for 13 weeks, respectively. Hens supplemented with Cd led to an impairment on production performance and egg quality with decreased egg production (EP), egg mass (EM), feed intake (FI), eggshell color, eggshell thickness, yolk color, albumen height and haugh unit and increased the feed conversion ratio (FCR) (p < 0.05). Cd treatment decreased the contents of cysteine (Cys), histidine (His), lithium (Li), aluminum (Al), chromium (Cr), manganese (Mn), nickel (Ni), zinc (Zn), arsenic (As), Se, strontium (Sr), stannum (Sn), mercury (Hg) and thallium (Tl) and increased the contents of isoleucine (Ile) and Cd (p < 0.05). Cd destroyed the egg yolk and serum redox states with the increased concentration of malondialdehyde (MDA) and the decreased activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) (p < 0.05). The expression levels of ovarian apoptotic genes (protein 53, Caspase9, Cytochrome c and Bcl-2 associated X protein) increased, and B-cell lymphoma 2 (Bcl-2) expression decreased in the Cd group (p < 0.05). Feeding Se significantly alleviated Cd-induced toxicity on performance and egg quality. Se+Cd treatment restored the balance between oxidation and antioxidant systems and modulated the elements' homeostasis and alleviated the changes in apoptotic-related genes expression levels. Se could alleviate the Cd toxicity to laying hens and their eggs but could not counteract all negative effects of Cd.

Nano-selenium alleviates cadmium-induced cerebellar injury by activating metal regulatory transcription factor 1 mediated metal response

This study aims to investigate the role of metal regulatory transcription factor 1 (MTF1)-mediated metal response in cadmium (Cd)-induced cerebellar injury, and to evaluate the antagonistic effects of nano-selenium (Nano-Se) against Cd toxicity. A total of 80 chicks (1 d old, male, Hy-Line Variety White) were randomly allocated to 4 treatment groups for 3 months: the control group (fed with a basic diet, n = 20), the Nano-Se group (basic diet with 1 mg/kg nano-Se 1 mg/kg Nano-Se in basic diet, n = 20), the Nano-Se + Cd group (basic diet with 1 mg/kg Nano-Se and 140 mg/kg CdCl₂, n = 20) and the Cd group (basic diet with 140 mg/kg CdCl₂ , n = 20). The results of the experiment showed that the Purkinje cells were significantly decreased with their degradation and indistinct nucleoli after Cd exposure. Moreover, exposure to Cd caused a significant accumulation of Cd and cupper. However, the contents of Se, iron, and zinc were decreased, thereby disturbing the metal homeostasis in the cerebellum. The Cd exposure also resulted in high levels of malondialdehyde (MDA) and down regulation of selenoprotein transcriptome. Furthermore, the expressions of MTF1, metallothionein 1 (MT1), MT2, zinc transporter 3 (ZNT3), ZNT5, ZNT10, zrt, irt-like protein 8 (ZIP8), ZIP10, transferrin (TF), ferroportin 1 (FPN1), ATPase copper transporting beta (ATP7B), and copper uptake protein 1 (CTR1) were inhibited by Cd exposure. However, all these changes were significantly alleviated by the supplementation of Nano-Se. This study proved that Cd could disorder metal homeostasis and induce oxidative stress, whereas Nano-Se could relieve all these negative effects caused by Cd via activating the MTF1-mediated metal response in the cerebellum of chicken.

Tannic acid antagonizes atrazine exposure-induced autophagy and DNA damage crosstalk in grass carp hepatocytes via NO/iNOS/NF-κB signaling pathway to maintain stable immune function

Atrazine (ATR) is a herbicide widely used in grass crops. The pollution of the soil and water environment is extremely harmful to aquatic animals and their offspring. iNOS/NO upregulation, DNA damage and cellular autophagy affect the immune function of fish liver cells. The effects of ATR at exposure doses on grass carp hepatocytes in terms of autophagy and DNA damage effects in genotoxicity, as well as the antagonistic effects of TAN on the above phenotypes and the internal mechanisms are not known. Therefore, we constructed control (Con group), ATR exposure (ATR group), TAN exposure (TAN group) and mixed group (ATR + TAN group) models on grass carp hepatocytes. Validation was performed by comet assay, MDC staining, qRT-PCR and protein blotting assay as well as iNOS/NO indicator levels and expression of immune factors as these experimental methods. Our data indicate that iNOS/NO assay kit measured that ATR treatment resulted in a significant increase in iNOS/NO activity and levels in grass carp hepatocytes (p < 0.05). We also found that NO/iNOS/NF-κB pathway genes were significantly activated (p < 0.05) at the exposure dose of ATR (3 μg mL-1). In addition, the proportion of cells that died due to DNA damage, autophagy, and immunotoxic effects was significantly increased at the exposure dose of ATR. Comet assay protein blotting detected increased DNA damage in cells at the ATR exposure dose (p < 0.05). MDC staining and qRT-PCR and protein blotting to detect the proportion of autophagic cells and autophagy-related genes also appeared upregulated at the exposed dose of ATR (p < 0.05). In brief, this study showed that ATR exposure caused cellular DNA damage and autophagy via the NO/iNOS/NF-κB axis, which led to immunotoxic effects and eventual death of grass carp hepatocytes. The present study facilitates the demonstration of the molecular mechanism of TAN alleviation of ATR cytotoxicity from the perspective of NO-mediated iNOS/NF-κB axis. It provides insights into the protection of farmed fish from agricultural contaminants and opens up new horizons in the use of natural plant-derived monomers for the clinical treatment of antagonistic triazine pesticide poisoning.

Selenium Mitigates Ammonia-Induced Neurotoxicity by Suppressing Apoptosis, Immune Imbalance, and Gut Microbiota-Driven Metabolic Disturbance in Fattening Pigs

Ammonia could be regarded as one detrimental pollutant with an acrid smell in livestock sheds. So far, the pig breeding industry became the main source of atmospheric ammonia. Previous literature demonstrated that excessive ammonia inhalation might cause a series of physiological damage to multiple organs. Unfortunately, the toxicity mechanisms of gaseous ammonia to the porcine nervous system need further research to elucidate. Selenium (Se) involves in many essential physiological processes and has a mitigative effect on the exogenous toxicant. There were scant references that corroborated whether organic Se could intervene in the underlying toxicity of ammonia to the hypothalamus. In the present study, multi-omics tools, ethology, and molecular biological techniques were performed to clarify the detailed mechanisms of relaxation effects of L-selenomethionine on ammonia poisoning. Our results showed that ammonia inhalation caused the clinical symptoms and the increment of positive apoptosis rate in the hypothalamus with the dysfunction of mitochondrial dynamics factors, while obvious mitochondria structure defects were observed. In parallel, the inflammation medium levels and gut microbes-driven metabolism function were altered to mediate the neurotoxicity in fattening pigs through the initiation of inflammation development. Interestingly, L-selenomethionine could attenuate ammonia toxicity by activating the PI3K/Akt/PPAR-γ pathway to inhibit the mitochondria-mediated apoptosis process, blocking the abnormal immune response and the accumulation of reactive oxygen species in the nucleus. Meanwhile, Se could enhance the production performance of fattening sows. Taken together, our study verified the novel hypothesis for the toxicity identification of aerial ammonia and provided a therapeutic strategy for the treatment of occupational poisoning.

Cadmium induces apoptosis by miR-9-5p targeting PTEN and regulates the PI3K/AKT pathway in the piglet adrenal gland

Cadmium (Cd) is an environmental pollutant that can cause endocrine organ damage. To explore the effect of subacute CdCl₂ exposure on piglet adrenal gland tissue and its mechanism based on the establishment of this model, bioinformatics, TUNEL assay, western blot (WB), and qRT-PCR methods were used to detect related indicators. The results showed that after Cd exposure, antioxidant enzymes decreased, heat shock protein increased, and miR-9-5p-gene of phosphatase and tensin homolog (PTEN) upregulates the phosphatidylinositol-3-kinase (PI3K/AKT) pathway. After this pathway was activated, the expression of the apoptosis-related factors cysteinyl aspartate-specific proteinase 3 and 9 (caspase 3 and 9), B-cell lymphoma-2-associated X (BAX) was increased sharply, and the expression of B-cell lymphoma-2 (BCL2) was significantly decreased. The changes in these indicators indicate that Cd exposure induces apoptosis and causes tissue damage in the adrenal gland of piglets. This study aims to reveal the toxic effects of CdCl₂ in animals and will provide new ideas for the toxicology of Cd.

Yeast Selenium Exerts an Antioxidant Effect by Regulating the Level of Selenoprotein to Antagonize Cd-Induced Pyroptosis of Chicken Liver

Cadmium (Cd) exposure can cause multiple organ damage in humans and animals by causing oxidative stress. Organic selenium can antagonize the toxic damage of heavy metals by exerting antioxidant effects. Oxidative stress can activate NLRP3/Caspase1-dependent pyroptosis, but it is not clear whether yeast selenium (Se Y) can antagonize Cd-induced pyroptosis in the chicken liver. In this experiment, we studied the effects of CdCl₂ single, Se Y single, and combined exposure on the pyroptosis of chicken liver. The results showed that Cd exposure induced oxidative stress in the chicken liver, and the expression of Sepx1, SelU, SelT, GPx1, GPx4, Dio1, Dio2, Dio3, TrxR1, TrxR2, TrxR3, SelH, SelI, SelO, SelK, SelPb, Selpp, and Sel15 decreased. In addition, NLRP3 inflammasome complex (NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing (ASC), and pro-Caspase1), Cysteinyl aspartate specific proteinase (Caspase1), Interleukin-β (IL-1β), and Interleukin-18 (IL-18) were upregulated. The combined treatment of Se Y and Cd found that the antioxidant level and the expression level of selenoprotein recovered to the Se group, and the liver pyroptosis decreased. Principal component analysis and correlation analysis screened out that selenoprotein O (SelO) is negatively correlated with pyroptosis-related genes. In short, our data shows that Se Y exerts an antioxidant effect by increasing the expression of selenoproteins and antagonizing the pyroptosis of chicken liver induced by Cd. This study provides new ideas for the field of heavy metal toxicology research. And the selected SelO has an important reference significance for follow-up research.

Cadmium exposure causes mitochondrial fission and fusion disorder in the pig hypothalamus via the PI3K/AKT pathway

Cadmium (Cd) is the main environmental pollutant causing endocrine and nervous system dysfunction in animals. High doses of Cd cause cytotoxicity, including programmed necrosis and apoptosis, which has aroused widespread concern. Mitochondrial dynamics plays a key role in programmed necrosis and apoptosis of endocrine organs. Nevertheless, there is a lack of information on the relationship between Cd-induced programmed necrosis/apoptosis of the hypothalamus and the mitochondrial fusion-fission balance. Therefore, a hypothalamic injury model of Cd exposure was established by adding 20 mg/kg CdCl₂ to the basic pig diet for 40 days. Analysis of the Cd toxicity mechanism was conducted by inductively coupled plasma mass spectrometry, hematoxylin and eosin staining, the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, and quantitative reverse transcription-polymerase chain reaction, as well as western blot analyses. The results suggested that exposure to Cd inhibited the expression of PI3K and AKT, interfered with the balance of mitochondrial fusion and division, downregulated the expression of Mfn2, Mfn1, and OPA1, and upregulated the expression of Drp1 and Mff, which led to cell apoptosis and programmed necrosis in the pig hypothalamus. This study finds that cadmium exposure leads to mitochondrial fission and fusion dysfunction in porcine hypothalamus via the PI3K/AKT pathway.

Effects of dietary supplementation with selenium yeast and jujube powder on mitochondrial oxidative damage and apoptosis of chicken

The main objective of this study was to explore the effects of dietary selenium yeast and jujube powder on mitochondrial oxidative damage and cell apoptosis of broilers during postmortem aging, chicken breasts of broilers fed diets supplemented with different concentrations of selenium yeast and jujube powder were used as research subjects. With the prolongation of postmortem aging time, the levels of reactive oxygen species (ROS), carbonyl content, mitochondrial permeability transition pore (MPTP) openness, and mitochondrial membrane permeability increased significantly (P < 0.05). The contents of the sulfhydryl, mitochondrial membrane potential, shear force, and cytochrome C (Cyt-c) reduction level decreased significantly (P < 0.05). The activity of Caspase-3 and Caspase-9 increased from 0 to 24 h postmortem but fell from 24 to 72 h postmortem. Compared with the control group, dietary selenium yeast and jujube powder significantly reduced mitochondrial oxidative damage. They greatly increased the shear force, mitochondrial membrane potential, and Cyt-c reduction levels (P < 0.05). Among them, the combination group of high-dose selenium yeast and jujube powder had more significant effects on ROS scavenging, reducing cell membrane permeability, protecting cell membrane integrity, and increasing Cyt-c reduction level (P < 0.05). In conclusion, cell apoptosis intensifies during the chicken breast's aging time, and muscle tenderness continues. Still, different doses of dietary selenium yeast and jujube powder can inhibit mitochondrial oxidation to various degrees. The combined group of selenium yeast and jujube powder with 0.6 mg·kg⁻¹ has the best effect. This study is of great significance for applying natural antioxidant ingredients such as selenium yeast and jujube powder in the development and utilization of poultry feed.

Cadmium Through Disturbing MTF1-Mediated Metal Response Induced Cerebellar Injury

Cadmium (Cd) is a toxic environmental contaminant, which bio-accumulate in animals through the food chain. Cerebellum is one of the primary target organs for Cd exposure. In this study, we established a chronic Cd exposure model; 60 chickens were treated with Cd (0 mg/kg, 35 mg/kg, 70 mg/kg) for 90 days. Clinical manifestations indicated that the chicken was depressed and has unstable gait under Cd exposure. Histopathological results indicated that Cd induced neuronal shrunken and indistinct nucleoli, and the number of Purkinje cells decreased significantly. Cerebellar metal contents were analyzed by ICP-MS. We found that Cd caused Cd and Cu accumulation and decreased the content of Se, Fe, and Zn, suggesting that Cd disturbed metal homeostasis. Besides, Cd treatment group also showed high levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) content and inhibited selenoprotein transcriptome, suggesting that Cd exposure resulted in oxidative stress. Notably, low-dose Cd exposure activated MTF1 mRNA and protein expression and its target metal-responsive genes, including MT1, MT2, DMT1, ZIP8, ZIP10, TF, and ATP7B which indicate cellular adaptive response against Cd-induced damage. On the other hand, 70 mg/kg Cd downregulated MTF1-mediated metal response, which was involved in Cd-induced cerebellar injury in chicken. In conclusion, our data demonstrated that molecular mechanisms are associated with Cd-induced cerebellar injury due to disturbing MTF1-mediated metal response.

Whole Transcriptome Profiling of the Effects of Cadmium on the Liver of the Xiangxi Yellow Heifer

Cadmium (Cd) is a major heavy metal toxicant found in industrial zones. Humans and animals are exposed to it through their diet, which results in various physiological problems. In the current study, the toxic effects of Cd on the liver were investigated by whole-transcriptome sequencing (RNA-seq) of the livers of Xiangxi heifers fed a diet with excess Cd. We randomly divided six healthy heifers into two groups. The first group received a control diet, whereas the second group received Cd-exceeding diets for 100 days. After 100 days, the livers were collected. A total of 551 differentially expressed mRNAs, 24 differentially expressed miRNAs, and 169 differentially expressed lncRNAs were identified (p < 0.05, |log2FC| >1). Differentially expressed genes (DEGs) were analyzed by gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses. We found that under Cd exposure, DEGs were enriched in the adenosine 5'-monophosphate-activated protein kinase pathway, which is involved in autophagy regulation, and the peroxisome proliferator-activated receptor pathway, which is involved in lipid metabolism. In addition, the apolipoprotein A4 gene, which has anti-inflammatory and antioxidant effects, the anti-apoptotic gene ATPase H+/K+ transporting the nongastric alpha2 subunit, and the cholesterol metabolism-associated gene endothelial lipase gene were significantly downregulated. C-X-C motif chemokine ligand 3, cholesterol 7α-hydroxylase, and stearoyl-CoA desaturase, which are involved in the development of fatty liver, were significantly upregulated. These genes revealed the main effects of Cd on the liver of Xiangxi yellow heifers. The current study provides insightful information regarding the DEGs involved in autophagy regulation, apoptosis, lipid metabolism, anti-inflammation, and antioxidant enzyme activity. These may serve as useful biomarkers for predicting and treating Cd-related diseases in the future.

Rutin Ameliorates Cadmium-Induced Necroptosis in the Chicken Liver via Inhibiting Oxidative Stress and MAPK/NF-κB Pathway

Cadmium (Cd) is a recognized toxic metal and exerts serious hepatotoxicity in animals and humans. Rutin (RUT) is a dietary bioflavonoid with strong antioxidant and anti-inflammatory potential. However, little is known about the alleviating effect of RUT against Cd-induced liver necroptosis. The aim of this study was to ascertain the ameliorative mechanism of RUT on necroptosis triggered by Cd in chicken liver. One hundred twenty-eight 100-day-old Isa hens were randomly divided into four groups: the control group, RUT group, Cd + RUT cotreated group, and Cd group. Cd exposure prominently elevated Cd accumulation and the activities of liver function indicators (ALT and AST). Furthermore, the histopathological results, the overexpression of genes (RIPK1, RIPK3, and MLKL) related to the necroptosis pathway, and low Caspase 8 levels in Cd-exposed chicken liver indicated that Cd intoxication induced necroptosis in chicken liver. Meanwhile, Cd administration drastically increased the levels of oxidizing stress biomarkers (ROS production, MDA content, iNOS activity, and NO generation), and obviously reduced the activities of antioxidant enzymes (SOD, GPx, and CAT) and total antioxidant capacity (T-AOC) in chicken liver. Cd treatment promoted the expression of the main members of the MAPK and NF-κB pathways (JNK, ERK, P38, NF-κB, and TNF-α) and activated heat shock proteins (HSP27, HSP40, HSP60, HSP70, and HSP90). However, RUT application remarkably alleviated these Cd-induced variations and necroptosis injury. Overall, our study demonstrated that RUT might prevent Cd-induced necroptosis in the chicken liver by inhibiting oxidative stress and MAPK/NF-κB pathway.

Identification of epigenetic modifications mediating the antagonistic effect of selenium against cadmium-induced breast carcinogenesis

The antagonistic effect of selenium (Se) against cadmium (Cd)-induced breast carcinogenesis was reported, but underlying mechanisms were unclear. The aim of this study was to identify the epigenetically regulated genes and biological pathways mediating the antagonistic effect. We exposed MCF-7 cells to Cd and Se alone or simultaneously. Cell proliferation was assessed by MTT assay, and differential epigenome (DNA methylation, microRNA, and long non-coding RNA) was obtained by microarrays. We cross-verified the epigenetic markers with differential transcriptome, and the ones modulated by Cd and Se in opposite directions were regarded to mediate the antagonistic effect. The epigenetically regulated genes were validated by using gene expression data in human breast tissues. We further assessed the biological functions of these validated genes. Our results showed that Se alleviated the proliferative effect of Cd on MCF-7 cell. A total of 10 epigenetically regulated genes were regarded to mediate the antagonistic effect, including APBA2, KIAA0895, DHX35, CPEB3, SVIL, MYLK, ZFYVE28, ABLIM2, GRB10, and PCDH9. Biological function analyses suggested that these epigenetically regulated genes were involved in multiple cancer-related pathways, such as focal adhesion and PI3K/Akt pathway. In conclusion, we provided evidence that Se antagonized the Cd-induced breast carcinogenesis via epigenetic modification and revealed the critical pathways.

The antagonistic effect of selenium on lead-induced apoptosis and necroptosis via P38/JNK/ERK pathway in chicken kidney

Lead (Pb), as a toxic heavy metal pollutant, has been paid much attention. Pb is often discharged into the environment through the soot, wastewater and waste residue in industrial production, which poses a great threat to animal health. Selenium (Se) is a trace element known to antagonize the toxicity caused by heavy metals. However, the interaction between Se and Pb in chicken kidney and its specific biological mechanism are still unclear. So, we constructed chicken models of Pb exposure and Pb, Se co-exposure. Therefore, we used western blot and qRT-PCR to detect the expression of related genes. The results showed that Pb activated the MAPK signaling pathway by up-regulating the expression of MARK pathway genes to induce the expression of pro-apoptotic genes and necroptosis-related genes. Se can regulate the MARK signaling pathway and attenuated the expression of MAPK pathway genes altered by Pb to reduce apoptosis and necroptosis of chicken kidney cells. Our study gives new ideas for the specific mechanism of Pb nephrotoxicity and provides a reference for comparative medicine and clinical medication.

Nano-selenium attenuates mitochondrial-associated apoptosis via the PI3K/AKT pathway in nickel-induced hepatotoxicity in vivo and in vitro

The aim of this study was to investigate the protective effects of Nano-Se against nickel (Ni)-induced hepatotoxicity and the potential mechanism. Hence, we constructed in vivo and in vitro models of Ni-induced hepatotoxicity. Sprague-Dawley (SD) rats were exposed to nickel sulfate (NiSO₄ , 5.0 mg/kg, i.p.) with or without Nano-Se (0.5, 1, and 2 mg/kg, oral gavage) co-administration for 14 days, and HepG2 cells were exposed to NiSO₄ (1500 μM) with or without Nano-Se (20 μM) for 24 h. Nano-Se obviously prevented Ni-induced hepatotoxicity indicated by ameliorating pathological change and decreasing Ni accumulation in rat livers. Ni induced a significant increase in hepatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GSH-Px), and malondialdehyde (MDA) level, decreased the glutathione (GSH) content while compared to those in the control group. Nano-Se administration improved the hepatic antioxidant capacity through increase hepatic GSH contents and GSH-Px activity, decrease the activities of SOD, CAT, and MDA level. Nano-Se improved the cell viability, decreased active oxygen (ROS) generation and ameliorated morphological changes of nuclear structures in Ni-treated HepG2 cells. In addition, Nano-Se inhibited the Ni-induced increases of cytochrome c, caspase-9, cleaved caspase-3, increased PI3K and AKT phosphorylation both in vivo and in vitro. Besides, the PI3K inhibitor Y294002 could inhibit the protective effects of Nano-Se on apoptosis. Thus, Nano-Se significantly activates PI3K/AKT signaling to ameliorate apoptosis in Ni-induced hepatotoxicity.

Selenium-Alleviated Testicular Toxicity by Modulating Inflammation, Heat Shock Response, and Autophagy Under Oxidative Stress in Lead-Treated Chickens

Lead (Pb), a toxic pollutant, is toxic to the testis. However, biological events during testicular Pb poisoning were not well understood. Selenium (Se) has the ability to antagonize Pb toxicity. The purpose of this research was to clarify the relief mechanism of Se on testicular toxicity of Pb from the perspective of oxidative stress, inflammation, heat shock response, and autophagy in a chicken model. Sixty male Hyline chickens (7-day-old) were randomly assigned into four groups. The feeding program consisted of a commercial diet, a Se-supplemented diet (1 mg kg^-1 Se), a Pb-supplemented diet (350 mg L^-1 Pb), and a Se- and Pb-supplemented diet, respectively. On the 12th week, serums were collected to measure testosterone level and testes were removed to determine testis weight, histological structure, Pb and Se concentrations, oxidative stress indicators, and mRNA and protein expression of inflammatory cytokines, heat shock proteins, and autophagy-related genes. The results showed that Pb poisoning changed the histological structure of testes; decreased serum testosterone level, testis weight, catalase, glutathione-s-transferase, and total antioxidative capacity activities; increased hydrogen peroxide content; inhibited interleukin (IL)-2 and mammalian target of rapamycin expression; and promoted IL-4, IL-12β, heat shock proteins, Beclin 1, Dynein, autophagy-related proteins 5, light chain 3 (LC3)-I, and LC3-II expression in the testes of chickens. Se intervention mitigated the aforementioned alterations induced by Pb. In conclusion, Pb led to oxidative stress, which triggered inflammation, heat shock response, and autophagy. Se administration mitigated testicular toxicity of Pb mainly by mitigating oxidative stress in male chickens.

Tissue Bioaccumulation and Toxicopathological Effects of Cadmium and Its Dietary Amelioration in Poultry-a Review

Cadmium (Cd) has been recognized as one of the most toxic heavy metals, which is continuously discharged into environments through anthropogenic (industrial activities, fertilizer production, and waste disposal) and natural sources with anthropogenic sources contributing greater than the natural sources. Therefore, Cd concentration sometimes increases in feeds, fodders, water bodies, and tissues of livestock including poultry in the vicinity of the industrial areas, which causes metabolic, structural, and functional changes of different organs of all animals. In poultry, bioaccumulation of Cd occurs in several organs mainly in the liver, kidney, lung, and reproductive organs due to its continuous exposure. Intake of Cd reduces growth and egg laying performance and feed conversion efficiency in poultry. Chronic exposure of Cd at low doses can also alter the microscopic structures of tissues, particularly in the liver, kidney, brain, pancreas, intestine, and reproductive organs due to increased content of Cd in these tissues. Continuous Cd exposure causes increased oxidative stress at cellular levels due to over-production of reactive oxygen species, exhausting antioxidant defense mechanisms. This leads to disruption of biologically relevant molecules, particularly nucleic acid, protein and lipid, and subsequently apoptosis, cell damage, and necrotic cell death. The histopatholocal changes in the liver, kidneys, and other organs are adversely reflected in hemogram and serum biochemical and enzyme activities. The present review discusses about Cd bioaccumulation and histopathological alterations in different tissues, pathogenesis of Cd toxicity, blood-biochemical changes, and its different ameliorative measures in poultry.

Cadmium induced cerebral toxicity via modulating MTF1-MTs regulatory axis

Metal-responsive transcription factor 1 (MTF1) participates in redox homeostasis and heavy metals detoxification via regulating the expression of metal responsive genes. However, the exact role of MTF1 in Cd-induced cerebral toxicity remains unclear. Herein, we explored the mechanism of Cd-elicited cerebral toxicity through modulating MTF1/MTs pathway in chicken cerebrum exposed to different concentrations of Cd (35 mg, 70 mg, and 140 mg/kg CdCl₂) via diet. Notably, cerebral tissues showed varying degrees of microstructural changes under Cd exposure. Cd exposure significantly up-regulated the expression of metal transporters (DMT1, ZIP8, and ZIP10) with concomitant elevated Cd level, as determined by ICP-MS. Cd significantly altered other cerebral biometals concentrations (particularly, Zn, Fe, Se, Cr, Mo, and Pb) and redox balance, resulting in increased cerebral oxidative stress. More importantly, Cd exposure suppressed MTF1 mRNA and nuclear protein levels and its target metal-responsive genes, notably metallothioneins (MT1 and MT2), and Fe and Cu transporter genes (FPN1, ATOX1, and XIAP). Moreover, Cd disrupted the regulation of expression of selenoproteome (particularly, GPxs and SelW), and cerebral Se level. Overall, our data revealed that molecular mechanisms associated with Cd-induced cerebral damage might include over-expression of DMT1, ZIP8 and ZIP10, and suppression of MTF1 and its main target metal-responsive genes as well as several selenoproteins.

Polystyrene microplastics trigger hepatocyte apoptosis and abnormal glycolytic flux via ROS-driven calcium overload

Human health could be affected by the spread of microplastics in the food chain. Our previous research has indicated that microplastics accumulated in the liver and subsequently induce oxidative damage. However, the molecular events linking oxidative stress to calcium ion (Ca²⁺) signaling during microplastics stress remains elusive. The present research demonstrated that up-regulation of Orai 1 and stromal interaction molecule 1 (Stim1) expression participated in the microplastics-triggered Ca²⁺ overload, accompanied with the down-regulation of arcoplasmic reticulum Ca²⁺ ATPase (SERCA). However, when the protein expression of Stim1/SERCA is restored, microplastics-induced Ca²⁺ overload is ameliorated. Further analysis revealed that inhibiting the microplastics-induced Ca²⁺ overload was integral to prevent hepatocyte apoptosis and S phase arrest in the L02 hepatocyte. Simultaneously, we observed that inhibiting microplastics-evoked reactive oxygen species (ROS) could alleviate Ca²⁺ overload via reversing expression of store-operated Ca²⁺ channels (SOCs). These changes were accompanied by restoration of glycolytic flux, likely due to the regulation of AMP-activated protein kinase (AMPK)-PGC-1α signaling. Our findings highlight the role of SOCs at microplastics-evoked ROS in Ca²⁺ overload, and its a crucial step in triggering hepatocyte death. Collectively, this study reveals a regulatory paradigm that links ROS with AMPK and Ca²⁺ signaling in microplastics-triggered hepatotoxicity.

Protective effects of selenium yeast against cadmium-induced necroptosis through miR-26a-5p/PTEN/PI3K/AKT signaling pathway in chicken kidney

Cadmium (Cd) is a ubiquitous environmental pollutant of increasing worldwide concern to both humans and animals. Selenium yeast (Se-Y) is an organic selenium source that has been shown an advantage in antagonizing Cd-induced liver necroptosis in chicken. Herein, we described the discovery path of Se-Y antagonism in Cd-induced renal necroptosis in chicken through targeting miR-26a-5p/PTEN/PI3K/AKT signaling pathway. We set up four groups of chickens at random: control group (0.5 mg/kg Na₂SeO₃), Se-Y group (0.5 mg/kg Se-Y), Se-Y+Cd group (0.5 mg/kg Se-Y and 150 mg/kg CdCl₂) and Cd group (150 mg/kg CdCl₂ and 0.5 mg/kg Na₂SeO₃). Interestingly, we found Se-Y, but not Na₂SeO₃, significantly blocked Cd accumulation in the kidney and alleviated Cd-induced necroptosis through inhibiting the expression of RIP1, RIP3 and MLKL. Se-Y, activated miR-26a-5p expression, thereby down-regulated the expression of PTEN, resulting in the up-regulation of PI3K/AKT signaling pathway and the inhibition of oxidative stress in both Se-Y and Cd treated chickens. Besides that, Se-Y could also specifically reduce the expression levels of heat shock protein 60 (HSP60), HSP70 and HSP90 in Se-Y and Cd co-treated chickens. Taken together, our results showed that Se-Y has an added value to antagonize Cd-induced necroptosis in chicken kidney by regulating the miR-26a-5p/PTEN/PI3K/AKT signaling pathway and HSPs, indicating that Se-Y could serve as an effective antagonist on Cd-induced renal necroptosis in chickens.

Selenium-deficient diet induces necroptosis in the pig brain by activating TNFR1 via mir-29a-3p

Selenium (Se) deficiency is one of the crucial factors related to nervous system disease and necroptosis. MicroRNAs (miRNAs) play vital roles in regulating necroptosis. However, the mechanism of Se deficiency-induced necroptosis in the pig brain tissue and the role that miRNAs play in this process are unclear. Therefore, in this study, in vitro and pig models of Se deficiency were replicated, and electron microscopy, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays were performed. The results showed that brain cells typically undergo necrotic changes, and that Se deficiency suppresses mir-29a-3p, which increases the levels of TNFRSF1A (TNFR1). Subsequently, a distinct increase in the necroptosis markers (RIPK1, RIPK3, and MLKL) and an evident decrease in caspase 8 was observed. And the expression of 10 selenoproteins was decreased. Moreover, the in vitro experiments showed that the expression of mir-29a-3p decreased as the Se content in the medium decreased and the application of an mir-29a-3p inhibitor increased the number of necrotic cells and the accumulation of ROS, and these effects were inhibited by necrostatin-1 (Nec-1) and N-acetyl-cysteine (NAC), respectively. Taken together, we proved that Se deficiency induced necroptosis both in vitro and in vivo through the targeted regulation of TNFR1 by mir-29a-3p in the pig brain.

Nephroprotective and anti-inflammatory potential of aqueous extract from Persea americana seeds against cadmium-induced nephrotoxicity in Wistar rats

Cadmium is a toxic metal and poses a high environmental risk to animals and humans, alike. It is thus pertinent to search for medicinal plants in protecting against cadmium toxicity. This study aims at investigating the ability of aqueous extract of Persea americana seeds (AEPA) in ameliorating the toxic effects of cadmium in the kidneys of cadmium-exposed Wistar rats. Male Wistar rats were grouped into five, of six animals each. Different groups of animals received normal saline (control group), 200 mg/kg body weight AEPA, 400 mg/kg AEPA, and standard drug, Livolin Forte, respectively. A last group of animals was left untreated. To induce toxicity, all animals, except the control group, were exposed to cadmium (200 mg/L, as CdCl₂) in their main drinking water for 21 days. Biochemical analysis of serum kidney markers, oxidative stress and antioxidant status, as well as anti-inflammatory activities, was done using standard methods and kits. In silico analysis was performed on phytochemicals reported to be abundant in AEPA. Treatment with 400 mg/kg AEPA significantly reversed (P ≤ 0.05) the adverse effect of cadmium on serum creatinine, urea, uric acid and blood urea nitrogen, and restored (P ≤ 0.05) antioxidant status, evidenced by its significant effect on superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, reduced glutathione, and lipid peroxidation activities. AEPA, at 400 mg/kg also exhibited significant anti-inflammatory effects, which was shown by reduced interleukin-2 and tumour necrosis factor α activities. Molecular docking of phytochemicals with the selected protein target also confirmed the therapeutic potential of AEPA. The study concluded that aqueous extract of AEPA protects against cadmium-induced kidney toxicity and inflammation.

Albicanol antagonizes Cd-induced apoptosis through a NO/iNOS-regulated mitochondrial pathway in chicken liver cells

Cadmium (Cd) induces hepatocyte injury by oxidative stress. Albicanol is a sesquiterpenoid extracted from the medicinal plant Dryopteris fragrans that has previously been shown to exhibit anti-aging and antioxidant activity. In this study, we explored the mechanism of albicanol inhibition of the Cd-induced apoptosis of chicken hepatoma cells (LMH) by treating these cells with CdCl2 (25 μM) and/or albicanol (2.5 × 10-5 μg mL-1) for 24 h. Under Cd treatment, the research results showed that the apoptosis rate markedly increased in LMH cells. In addition, the iNOS activity and NO content increased significantly, which promoted the expressions of genes associated with the mitochondrial apoptosis pathway (Bax, CytC, Caspase-3 and Caspase-9) and inhibited the expression of Bcl-2 in this pathway. However, Cd + albicanol co-treatment significantly reduced the apoptosis rate and the expressions of iNOS and genes associated with the mitochondrial apoptosis pathway (Bax, CytC, Caspase-3 and Caspase-9), and promoted the expression of Bcl-2 in this pathway. In addition, molecular docking supported a link between the albicanol ligand and the iNOS receptor. These results indicated that albicanol can inhibit Cd-induced apoptosis by regulating the NO/iNOS-mediated mitochondrial pathway.

Comparison of nanoparticle-selenium, selenium-enriched yeast and sodium selenite on the alleviation of cadmium-induced inflammation via NF-kB/IκB pathway in heart

Cadmium (Cd) has been confirmed as an environmental contaminant, which potential threats health impacts to humans and animals. Selenium (Se) as a beneficial element that alleviates the negative effects of Cd toxicity. Se mainly exists in two forms in food nutrients including organic Se usually as (Se-enriched yeast (SeY)) and inorganic Se (sodium selenite (SSe)). Nanoparticle of Se (Nano-Se), a new form Se, which is synthesized by the bioreduction of Se species, which attracted significant attention recently. However, compared the superiority alleviation effects of Nano-Se, SeY or SSe on Cd-induced toxicity and related mechanisms are still poorly understood. The purpose of this study was to compare the superiority antagonism effects of Nano-Se, SeY and SSe on Cd-induced inflammation response via NF-kB/IκB pathway in the heart. The present study demonstrated that exposed to Cd obviously increased the accumulation of Cd, disruption of ion homeostasis and depressed the ratios of K⁺/Na⁺ and Mg²⁺/Ca²⁺ via ion chromatography mass spectrometry (ICP-MS) detecting the heart specimens. In the results of histological and ultrastructure observation, typical inflammatory infiltrate characteristics and mitochondria and nuclear structure alterations in the hearts of Cd group were confirmed. Cd treatment enhanced the inducible nitric oxide synthase (iNOS) activities and NOS isoforms expression via NF-kB/IκB pathway to promote inflammation response. However, the combined treatment of Cd-exposed animals with Nano-Se was more effective than SeY and SSe in reversing Cd-induced histopathological changes and iNOS activities increased, reducing Cd accumulation and antagonizing Cd-triggered inflammation response via NF-kB/IκB pathway in chicken hearts. Overall, Se applications, especially Nano-Se, can be most efficiently used for relieving cardiotoxicity by exposed to Cd compared to other Se compound.

Cadmium exposure induces inflammation and necroptosis in porcine adrenal gland via activating NF-κB/MAPK pathway

Cadmium (Cd) is a heavy metal harmful to animals and humans. Cd exposure causes inflammation or necroptosis in many tissues, including adrenal tissue. However, the current researches on the effects of Cd²⁺ in adrenal tissues are not enough. Therefore, in our experiment Cd chloride (CdCl₂) was added to the piglet's diet at a concentration of 20 mg/kg to study the effects of Cd²⁺ exposure on the porcine adrenal tissue. Our results showed that Cd²⁺ exposure could cause inflammation by activating the nuclear factor kappa-B (NF-κB) pathway, which in turn induced necroptosis in adrenal tissue with the activated mitogen-activated protein kinase (MAPK) pathway. The expression increase of inflammatory factors and necroptosis downstream genes, and the downregualtion of cysteinyl aspartate specific proteinase 8 (Caspase 8) proved that Cd²⁺ exposure caused inflammation and necroptosis in adrenal tissue. We conclude that this report provides more basic theoretical data for exploring the mechanism of adrenal injury.

MAPK, AKT/FoxO3a and mTOR pathways are involved in cadmium regulating the cell cycle, proliferation and apoptosis of chicken follicular granulosa cells

The occurrence of cadmium (Cd) in feed is a major problem in animal health and production. Studies have confirmed that Cd depresses egg production of laying hens, which is closely related to follicular atresia. This study aimed to assess the toxic impacts of Cd on the ovarian tissue, and to examine the mechanism of Cd-induced granulosa cell proliferation and apoptosis. Results from the nitric oxide (NO) and malondialdehyde (MDA) content, total superoxide dismutase (T-SOD), glutathione peroxide (GSH-Px), total nitric oxide synthase (T-NOS) and adenosine triphosphatase (ATPase) activities, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, and hematoxylin-eosin (H & E) staining indicated that excess Cd induced oxidative stress, granulosa cell apoptosis and follicular atresia in the layer ovary. Low-dose Cd exposure (1 μM) induced the granulosa cell proliferation, upregulated the mRNA levels of RSK1 and RHEB, activated FoxO3a, AKT, ERK1/2, mTOR and p70S6K1 phosphorylation, and promoted cell cycle progression from phase G1 to S. However, high-dose Cd exposure (15 μM) induced reactive oxygen species (ROS) generation and cell apoptosis, upregulated the mRNA levels of the inflammatory factors, ASK1, JNK, p38 and TAK1, downregulated the expressions of RSK1 and RHEB genes, and inhibited the phosphorylation of ERK1/2, mTOR and p70S6K1 proteins, and the cell cycle progression. Rapamycin pre-treatment completely blocked the phosphorylation of mTOR and p70S6K1 proteins, and the cell cycle progression induced by 1 μM Cd, and accelerated 15 μM Cd-induced cell apoptosis and cell cycle arrest. The microRNA sequencing result showed that 15 μM Cd induced differential expression of microRNA genes, which may regulate AKT, ERK1/2 and mTOR signaling and cell cycle progression by regulating the activity of G proteins and cell cycle-related proteins. Conclusively, these results indicated that Cd can cause the ovarian damage and follicular atresia, and regulate cell cycle, cell proliferation or apoptosis of granulosa cells through MAPK, AKT/FoxO3a and mTOR pathways in laying hens.

Dietary selenomethionine ameliorates lipopolysaccharide-induced renal inflammatory injury in broilers via regulating the PI3K/AKT pathway to inhibit necroptosis

Selenomethionine (SeMet) has antioxidant and anti-inflammatory effects, as a widely used organic Se source in food supplements, and its inhibitory effect on the prevention and treatment of renal inflammatory injury is unclear. Here, in order to explore the protective effect of SeMet on kidney tissue of broilers and determine its potential molecular mechanism, we took broilers as the research object, lipopolysaccharide (LPS) was used as the source of stimulation, and the model was established by adding SeMet to the diet. The histopathological observation indicated that SeMet alleviated the LPS-induced characteristic changes of renal inflammatory injury. Besides, SeMet inhibited LPS-induced PI3K, AKT, caspase 8 and IκB-α downregulation, the necroptosis marker genes (FADD, RIP1, RIP3, MLKL and TNF-α), pro-inflammatory factors (NF-κB, PTGEs, COX-2, iNOS, IL-1β and IL-6) and HSP60, HSP70 and HSP90 overexpression. We concluded that SeMet ameliorates LPS-induced renal inflammatory injury in broilers by inhibiting necroptosis via the regulation of the PI3K/Akt pathway. Thus, we speculated that dietary SeMet may be a potential new strategy for the treatment of renal injury.

Cadmium induces endoplasmic reticulum stress-mediated apoptosis in pig pancreas via the increase of Th1 cells

Cadmium (Cd), an environmental pollutant, causes several adverse reactions in animals. High dose of Cd has serious cytotoxicities, including the induction of programmed cell necrosis, autophagy and apoptosis, which has aroused wide public concern. The balance of cytokine network is affected by Th1/Th2 balance which is closely related to immune response and the occurrence, development, treatment and outcome of various diseases. Cd can induce severe apoptosis, but the relationship between Cd induced apoptosis and Th1/Th2 balance has not been clarified. In this study, we established a pig Cd poisoning model, exposing to CdCl₂ for 40 days (20 mg Cd/kg diet). Firstly, deviation of Th1/Th2 balance was observed by fluorescence staining, and apoptosis was observed by TUNEL staining. Then, real-time fluorescence quantitative analysis and Western blot were used to detect the expression of related proteins. The results show that Cd can interfere with the balance of Th1/Th2 and shift the balance towards Th1. In addition, through the experiments, we found that Cd exposure can increase the expression of glucose-regulated protein 94 (GRP94) and glucose-regulated protein 78 (GRP78), marker proteins of unfolded protein response (UPR). Cd exposure can increase the expression of pancreatic endoplasmic reticulum kinase (PERK), CCAAT-enhancer-binding protein homologous protein (CHOP), inositol-requiring enzyme 1 (IRE-1), activating transcription factor 6 (ATF-6), cysteinyl aspartate specific proteinase (Caspase12), indicating the three branches (ATF6, PERK and IRE-1) of endoplasmic reticulum stress (ER-stress) were activated. Moreover, we found that the expression of pro-apoptosis genes in the downstream pathway of ER-stress increased. In summary, our results indicated that Cd exposure upregulated the expression of pro-apoptosis related genes and caused apoptosis via the activation of the ER-stress signaling pathways in pancreas cells. And these negative effects were correlated with the equilibrium drift of Th1/Th2, increase in the expression and secretion of Th1 cytokines.

MicroRNA-363-3p promotes apoptosis in response to cadmium-induced renal injury by down-regulating phosphoinositide 3-kinase expression

We previously determined that specific microRNAs (miRNAs) are involved in renal pathophysiological occurrences induced by cadmium (Cd) in rats. This study expands our studies on miRNAs, determining their role in Cd-induced nephrotoxicity in occupational workers. We performed miRNA microarray analyses of blood and urine samples from patients diagnosed as occupational chronic Cd poisoning (OCCP) with abnormally elevated concentrations of urinary beta-2-microglobulin (U-β₂-MG), an indicator of tubular proteinuria. We also performed in vitro bioinformatics-based investigations of apoptosis-related genes targeted by miRNAs involved in the biological response to Cd exposure. We tested five differentially expressed miRNAs and determined a significant increase of sera miR-363-3p. Also, we determined that miR-363-3p increase is associated with phosphoinositide 3-kinase (PI3K) down-regulation and the suppressed proliferation and enhanced apoptosis of renal tubule epithelial cells. The obtained results suggest miR-363-3p involvement in the pathophysiology of Cd-induced renal injury in humans and maybe considered for possible interventional therapeutic strategies for Cd-associated kidney damage.