Calcium overload and reactive oxygen species accumulation induced by selenium deficiency promote autophagy in swine small intestine

Selenium represses microRNA-202-5p/MICU1 aixs to attenuate mercuric chloride-induced kidney ferroptosis

Mercuric chloride (HgCl2) is a nephrotoxic contaminant that is widely present in the environment. Selenium (Se) can effectively antagonize the biological toxicity caused by heavy metals. Here, in vivo and in vitro models of Se antagonism to HgCl2-induced nephrotoxicity in chickens were established, with the aim of exploring the specific mechanism. Morphological observation and kidney function analysis showed that Se alleviated HgCl2-induced kidney tissue injury and cytotoxicity. The results showed that ferroptosis was the primary mechanism for the toxicity of HgCl2, as indicated by iron overload and lipid peroxidation. On the one hand, Se significantly prevented HgCl2-induced iron overload. On the other hand, Se alleviated the intracellular reactive oxygen species (ROS) levels caused by HgCl2. Subsequently, we focused on the sources of ROS during HgCl2-induced ferroptosis. Mechanically, Se reduced ROS overproduction induced by HgCl2 through mitochondrial calcium uniporter (MCU)/mitochondrial calcium uptake 1 (MICU1)-mediated mitochondrial calcium ion (Ca2+) overload. Furthermore, a dual luciferase reporter assay demonstrated that MICU1 was the direct target of miR-202-5p. Overall, Se represses miR-202-5p/MICU1 axis to attenuate HgCl2-induced kidney ferroptosis.

Protective effect of 3-bromo-4,5-dihydroxybenzaldehyde against PM2.5-induced cell cycle arrest and autophagy in keratinocytes

Particulate matter 2.5 (PM2.5) poses a serious threat to human health and is responsible for respiratory disorders, cardiovascular diseases, and skin disorders. 3-Bromo-4,5-dihydroxybenzaldehyde (3-BDB), abundant in marine red algae, exhibits anti-inflammatory, antioxidant, and antidiabetic activities. In this study, we investigated the protective mechanisms of 3-BDB against PM2.5-induced cell cycle arrest and autophagy in human keratinocytes. Intracellular reactive oxygen species generation, DNA damage, cell cycle arrest, intracellular Ca2+ level, and autophagy activation were tested. 3-BDB was found to restore cell proliferation and viability which were reduced by PM2.5. Furthermore, 3-BDB reduced PM2.5-induced reactive oxygen species levels, DNA damage, and attenuated cell cycle arrest. Moreover, 3-BDB ameliorated the PM2.5-induced increases in cellular Ca2+ level and autophagy activation. While PM2.5 treatment reduced cell growth and viability, these were restored by the treatment with the autophagy inhibitor bafilomycin A1 or 3-BDB. The findings indicate that 3-BDB ameliorates skin cell death caused by PM2.5 via inhibiting cell cycle arrest and autophagy. Hence, 3-BDB can be exploited as a preventive/therapeutic agent for PM2.5-induced skin impairment.

Bisphenol A Regulates the TNFR1 Pathway and Excessive ROS Mediated by miR-26a-5p/ADAM17 Axis to Aggravate Selenium Deficiency-Induced Necroptosis in Broiler Veins

Selenium (Se) deficiency can affect the expression of microRNA (miRNA) and induce necroptosis, apoptosis, etc., resulting in damage to various tissues and organs. Bisphenol A (BPA) exposure can cause adverse consequences such as oxidative stress, endothelial dysfunction, and atherosclerosis. The toxic effects of combined treatment with Se-deficiency and BPA exposure may have a synergistic effect. We replicated the BPA exposure and Se-deficiency model in broiler to investigate whether the combined treatment of Se-deficiency and BPA exposure induced necroptosis and inflammation of chicken vascular tissue via the miR-26A-5p/ADAM17 axis. We found that Se deficiency and BPA exposure significantly inhibited the expression of miR-26a-5p and increased the expression of ADAM17, thereby increasing reactive oxygen species (ROS) production. Subsequently, we discovered that the tumor necrosis factor receptor (TNFR1), which was highly expressed, activated the necroptosis pathway through receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3), and mixed-lineage kinase domain-like (MLKL), and regulated the heat shock proteins-related genes expressions and inflammation-related genes expressions after exposure to BPA and selenium deficiency. In vitro, we found that miR-26a-5p knockdown and increased ADAM17 can induce necroptosis by activating the TNFR1 pathway. Similarly, both N-Acetyl-L-cysteine (NAC), Necrostatin-1 (Nec-1), and miR-26a-5p mimic prevented necroptosis and inflammation caused by BPA exposure and Se deficiency. These results suggest that BPA exposure activates the miR-26a-5p/ADAM17 axis and exacerbates Se deficient-induced necroptosis and inflammation through the TNFR1 pathway and excess ROS. This study lays a data foundation for future ecological and health risk assessments of nutrient deficiencies and environmental toxic pollution.

Polystyrene microplastics mediate cell cycle arrest, apoptosis, and autophagy in the G2/M phase through ROS in grass carp kidney cells

Microplastics (MPs) have attracted widespread worldwide attention as a new pollutant. However, the role of reactive oxygen species (ROS) and cell cycle in nephrotoxicity induced by different concentrations of polystyrene microplastics (PS-MPs) is unknown. This study used grass carp kidney cells (CIK) treated with different concentrations of PS-MPs (0, 0.012, 0.0625, and 0.5 mg L-1 ) as subjects. With the increase of PS-MPs concentration, the levels of ROS and malonaldehyde increased, while the level of total antioxidant capacity, superoxide Dismutase (SOD), and glutathione (GSH) activity decreased. The expression of BUB1 mitotic checkpoint serine/threonine kinase (BUB1), cyclin-dependent kinase (CDK1), CDK2, CyclinB1, cell division cycle 20 homolog (CDC20), and B-cell lymphoma-2, sequestosome 1 decreased significantly. Nevertheless, the expression of Caspase 3, Cleave-Caspase 3, cytochrome c (Cytc), BCL2-associated X, apoptosis regulator, poly ADP-ribose polymerase (PARP), Cleave-PARP, Caspase 9, autophagy immunoblot kit (LC3), and Beclin1 increased. Our research shows that PS-MPs can trigger oxidative stress and induce cell cycle arrest, apoptosis, and autophagy in CIK cells by regulating ROS. This work provides a theoretical basis for cellular biology and toxicology mechanisms and new insights into the potential risks to animals from MPs exposure in the environment.

Selenium Status of Southern Africa

Selenium is an essential trace element that exists in inorganic forms (selenite and selenates) and organic forms (selenoamino acids, seleno peptides, and selenoproteins). Selenium is known to aid in the function of the immune system for populations where human immunodeficiency virus (HIV) is endemic, as studies suggest that a lack of selenium is associated with a higher risk of mortality among those with HIV. In a recent study conducted in Zambia, adults had a median plasma selenium concentration of 0.27 μmol/L (IQR 0.14-0.43). Concentrations consistent with deficiency (<0.63 μmol/L) were found in 83% of adults. With these results, it can be clearly seen that selenium levels in Southern Africa should be investigated to ensure the good health of both livestock and humans. The recommended selenium dietary requirement of most domesticated livestock is 0.3 mg Se/kg, and in humans above 19 years, anRDA (recommended daily allowance) of 55 mcg Se/per dayisis recommended, but most of the research findings of Southern African countries have recorded low levels. With research findings showing alarming low levels of selenium in soils, humans, and raw feed materials in Southern Africa, further research will be vital in answering questions on how best to improve the selenium status of Southern African soils and plants for livestock and humans to attain sufficient quantities.

Selenium deficiency caused hepatitis in chickens via the miR-138-5p/SelM/ROS/Ca2+ overload pathway induced by hepatocyte necroptosis

Selenoprotein M (SelM), a key thioredoxin like enzyme in the endoplasmic reticulum (ER), is closely related to hepatocyte degeneration. However, the role of miR-138-5p/SelM and necroptosis in chicken SelM-deficient hepatitis and the specific biological mechanism of liver inflammation caused by SelM deficiency have not been elucidated. We established an in vivo chicken liver Se deficiency model by feeding a low-Se diet. The miR-138-5p knockdown and overexpression models and SelM knockdown models were established in LMH cells for an in vitro study. Transmission electron microscopy, H&E staining, Fluo4-AM/ER staining, and flow cytometry were used to detect the morphological changes in chicken liver tissue and the expression changes of necroptosis and inflammation in chicken liver cells. We observed that Se deficiency resulted in liver inflammation, up-regulation of miR-138-5p expression and down-regulation of SelM expression in chickens. Oxidative stress, Ca2+ overload, energy metabolism disorder and necroptosis occurred in chicken liver tissue. Importantly, ROS and the Ca2+ inhibitor could effectively alleviate the energy metabolism disorder, necroptosis and inflammatory cytokine secretion caused by miR-138-5p overexpression and SelM knockdown in LMH cells. In conclusion, selenium deficiency causes hepatitis by upregulating miR-138-5p targeting SelM. Our research findings enrich our knowledge about the biological functions of SelM and provide a theoretical basis for the lack of SelM leading to liver inflammation in chickens.

Supression Thioredoxin reductase 3 exacerbates the progression of liver cirrhosis via activation of ferroptosis pathway

AIMS

In the past decades, Txnrd3 as selenoprotein is considered to be highly expressed in testis and participate in sperm mature; however its role in liver diseases needs further study. Iron is essential for humans and animals, while its overload could damage to multiple organs. However, role of Txnrd3 and iron in cirrhosis is still unclear.

MATERIALS AND METHODS

Forty 8-week-old wild-type and forty Txnrd3-/- mice were selected to build liver cirrhosis model using Thiacetamide solution, deposition of iron in liver was observed via Prussian blue staining. Txnrd3 overexpression/knockdown model in vitro was constructed based on cell transfection techniques in AML12 cells, expression abundance of ferroptosis pathway genes within cells and tissues were determined by qRT-PCR and Western Blot.

KEY FINDINGS

Results showed that Txnrd3-/- mice developed more pronounced liver damage, accompanied by reduced GPX4 expression and iron deposition. A significant decrease in the expression abundance of GPX4 was also detected in Txnrd3 knock-down AML12 cells. In summary, Txnrd3 knockdown could result in iron overload and ferroptosis pathway activation within liver tissues and hepatocytes, ultimately lead to the occurrence of liver injury and cirrhosis.

SIGNIFICANCE

These results will provide biological markers for early diagnosis during cirrhosis and lay a theoretical basis for clinical therapy.

Astilbin Attenuates Cadmium-Induced Adipose Tissue Damage by Inhibiting NF-κB Pathways and Regulating the Expression of HSPs in Chicken

Cadmium (Cd) can damage tissues by inducing oxidative stress, lymphocyte infiltration, and inflammation in these sites. Meanwhile, astilbin (Ast) is an antioxidant agent. At present, only a few mechanisms of Cd-induced adipose tissue damage have been described. Herein, we assessed the potential protective effects and the molecular mechanism underlying the antioxidant properly of Ast after Cd intake in chicken adipose tissue. In this study, a total of 160 7-day-old roosters were randomly divided into four groups. Roosters were fed with a basic diet (C group), Ast 40 mg/kg (Ast group), CdCl₂ 150 mg/kg + Ast 40 mg/kg (Cd/Ast group), and CdCl₂ 150 mg/kg (Cd group) for 60 days. We found that Cd intake changed the morphology and structure of adipose tissues and decreased the expression of several antioxidants, including total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and total antioxidant capacity (T-AOC), but increased those of oxidative stress markers including malondialdehyde (MDA), inducible nitric oxide synthase (iNOS), NO, and H2O2. Cd further activated the nuclear factor kappa B (NF-κB) signaling pathway and increased the expression of the inflammation-related mediators, interleukin 1beta (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), cyclooxygenase-2 (COX-2), iNOS, prostaglandin E synthase (PTGES), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ). Cd-induced oxidative stress upregulated the expression of three heat shock proteins (HSPs), including HSP27, HSP70, and HSP90. Summarily, Cd causes oxidative stress-mediated tissue damage by activating the NF-κB pathway, promoting inflammation and upregulating the expression of HSPs. However, Ast supplementation modulates oxidative stress in adipose tissue by inhibiting inflammation mediated by the NF-κB pathway and regulating the expression of HSPs.

Selenium Deficiency Caused Fibrosis as an Oxidative Stress-induced Inflammatory Injury in the Lungs of Mice

Selenium (Se) is a vital trace element in the regulation of inflammation and antioxidant reactions in both animals and humans. Se deficiency is rapidly affecting lung function. The present study investigated the molecular mechanism of Se deficiency aggravates reactive oxygen species (ROS)-induced inflammation, leading to fibrosis in lung. Mice fed with different concentrations of Se to establish the model. In the Se-deficient group, the ROS and malondialdehyde (MDA) was increased, and the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and catalase (CAT) reduced. The histopathological observation showed that Se deficiency lead to lung texture damage with varying degrees of degeneration, necrosis, shedding of some alveolar epithelial cells, and inflammatory cell infiltration. Immunohistochemistry showed that the expression of α-smooth muscle actin (α-SMA) increased. The fibrosis index was verified with Sirius red staining. The ELISA and qPCR results showed that the inflammatory cytokines (TNF-α and IL-1β) and ECM (collagen I, collagen IV, fibronectin, and laminin) were increased with ROS increasing, which was induced by Se deficiency. The results displayed that oxidative stress with Se deficiency led to an increase in tissue inhibitors of metalloproteinase (TIMPs), but a decrease in matrix metalloproteinases (MMPs). All the results indicated that Se deficiency induced excessive ROS accumulation to generate inflammation, which disrupted ECM homeostasis and aggravated fibrosis in the lung.

The role of selenoprotein M in nickel-induced pyroptosis in mice spleen tissue via oxidative stress

Nickel (Ni) is a heavy metal element and a pollutant that threatens the organism's health. Melatonin (Mel) is an antioxidant substance that can be secreted by the organism and has a protective effect against heavy metals. Selenoprotein M (SelM) is a selenoprotein widely distributed of the body, and its role is to protect these tissues from oxidative damage. To study the mechanism of Ni, Mel, and SelM in mouse spleen, 80 SelM^+/+ wild-type and 80 SelM^-/- homozygous mice were divided into 8 groups with 20 mice in each group. The Ni group was intragastric at a concentration of 10 mg/kg, while the Mel group was intragastric at 2 mg/kg. Mice were injected with 0.1 mL/10 g body weight for 21 days. Histopathological and ultrastructural observations showed the changes in Ni, such as the destruction of white and red pulp and the appearance of pyroptosomes. SelM knockout showed more severe injury, while Mel could effectively interfere with Ni-induced spleen toxicity. The results of antioxidant capacity determination showed that Ni could cause oxidative stress in the spleen, and Mel could also effectively reduce oxidative stress. Finally, Ni exposure increased the expression levels of the pyroptotic genes, including apoptosis-associated speck protein (ASC), absent in melanoma-2 (AIM2), NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), Caspase-1, interleukin- (IL-) 18, and IL-1β (p < 0.05). Loss of SelM significantly increased these (p < 0.05), while Mel decreased the alleviated impact of Ni. In conclusion, the loss of SelM aggravated Ni-induced pyroptosis of the spleen via activating oxidative stress, which was alleviated by Mel, but the effect of Mel was not obvious in the absence of SelM, which reflected the important role of SelM in Ni-induced pyroptosis.

Selenium deficiency increased duodenal permeability and decreased expression of antimicrobial peptides by activating ROS/NF-κB signal pathway in chickens

Selenium (Se) is an essential trace element for the body. Various organs of the body, including the intestine, are affected by its deficiency. Se deficiency can induce oxidative stress and inflammatory responses in the intestine. It can also increase intestinal permeability and decrease intestinal immune function in mammals. However, the detailed studies, conducted on the intestinal molecular mechanisms of Se deficiency-induced injury in poultry, are limited. This study explored the adverse effects of Se deficiency on intestinal permeability and its mechanism. A Se-deficient chicken model was established, and the morphological changes in the chicken duodenum tissues were observed using a light microscope and transmission electron microscope (TEM). Western blotting, qRT-PCR, and other methods were used to detect the expression levels of selenoproteins, oxidative stress indicators, inflammatory factors, tight junction (TJ) proteins, antimicrobial peptides, and other related indicators in intestinal tissues. The results showed that Se deficiency could decrease the expression levels of selenoproteins and antioxidant capacity, activate the nuclear factor kappa-B (NF-κB) pathway, cause inflammation, and decrease the expression levels of TJ proteins and antimicrobial peptides in the duodenum tissues. The study also demonstrated that Se deficiency could increase intestinal permeability and decrease antimicrobial peptides via reactive oxygen species (ROS)/NF-κB. This study provided a theoretical basis for the scientific prevention and control of Se deficiency in poultry. Se deficiency decreased the expression levels of selenoproteins and increased ROS levels to activate the NF-κB pathway, resulting in the production of pro-inflammatory cytokines, reducing the expression levels of TJ protein, and weakening the expression of antimicrobial peptides, which contributed to the higher intestinal permeability. Oxidative stress weakened the expression of antimicrobial peptides.

Decreased thioredoxin reductase 3 expression promotes nickel-induced damage to cardiac tissue via activating oxidative stress-induced apoptosis and inflammation

Thioredoxin reductase 3 (Txnrd3) plays a crucial role in antioxidant and anti-cancer activities, and sperm maturation. The damage of heavy metals, including Nickel (Ni), is the most prominent harm in social development, and hampering Txnrd3 might exacerbate Ni-induced cardiac damage. In this study, a total of 160 8-week-old C57BL/N male mice with 25-30 g weight of Txnrd3+/+ wild-type and Txnrd3-/- homozygote-type were randomly divided into eight groups. The mice in the control and Ni groups were gavaged with distilled water and a freshly prepared 10 mg/kg NiCl₂ solution. Melatonin (Mel) groups were administered at a concentration of 2 mg/kg for 21 days at the mice's 0.1 ml/10 g body weight. Ni exposure up-regulated the messenger RNA (mRNA) levels of mitochondrial apoptosis (caspase-3, caspase-9, cytochrome c, p53, and BAX), autophagy (LC3, ATG 1, ATG 7, and Beclin-1), and inflammation (TNF-α, COX 2, IL-1β, IL-2, IL-6, and IL-7)-related markers, but down-regulated the mRNA levels of BCL-2, p62 and mTOR (p < .05). Ni exposure decreased the expression of BCL-2 and p62 protein but increased the expression levels of caspase-3, caspase-9, cytochrome c, p53, BAX, ATG 7, Beclin-1, TNF-α, COX 2, IL-1β and IL-2 protein (p < .05). Ni increased the contents of glutathione disulfide (GSSG) and malondialdehyde (MDA) and decreased the activities of catalase (CAT) and total superoxide dismutase (T-SOD) (p < .05). Decreased Txnrd3 expression significantly exacerbated changes compared to the Ni exposure (p < .05). Mel significantly attenuated these changes, but the effect decreased when Txnrd3 was inhibited (p < .05). In conclusion, decreased Txnrd3 expression promoted Ni-induced mitochondrial apoptosis and inflammation via oxidative stress and aggravated heart damage in mice. Decreased Txnrd3 expression significantly reduced the protective effect of Mel to Ni exposure.

Molybdenum and cadmium co-exposure induces CaMKKβ/AMPK/mTOR pathway mediated-autophagy by subcellular calcium redistribution in duck renal tubular epithelial cells

Excessive molybdenum (Mo) and cadmium (Cd) are toxic environmental pollutants. Our previous research confirmed excessive Mo and Cd co-induced calcium homeostasis disorder and autophagy in duck kidneys, but how calcium ion (Ca²⁺) regulates autophagy is unclear. The results revealed that the Mo- and/or Cd-induced cytosolic Ca²⁺ concentration ([Ca²⁺]_c) increase mainly came from intracellular calcium stores. Mo and/or Cd caused mitochondrial Ca²⁺ content ([Ca²⁺]_mit) and [Ca²⁺]_c increase with endoplasmic reticulum (ER) Ca²⁺ content ([Ca²⁺]_ER) decrease and upregulated calcium homeostasis-related factor expression levels, but 2-Aminoethoxydiphenyl borate (2-APB) reversed subcellular Ca²⁺ redistribution. Increased Phospholipase C (PLC) and inositol 1,4,5-trisphosphate (IP₃) activities and inositol 1,4,5-trisphosphate receptor (IP₃R) expression level were observed in Mo- and/or Cd-treated cells, which was reversed by the PLC inhibitor U-73122. 2-APB and 1,2-Bis (2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) addition mitigated [Ca²⁺]_c and autophagy (variations in microtubule-associated protein light chain 3 (LC3), LC3B-II/LC3B-I, autophagy related 5 (ATG5), sequestosome-1(P62), programmed cell death-1 (Beclin-1) and Dynein expression levels, LC3 puncta, autophagosomes and acid vesicle organelles) under Mo and/or Cd treatment, respectively, while thapsigargin (TG) had the opposite impacts. Additionally, the calmodulin-dependent protein kinase kinase β (CaMKKβ) inhibitor STO-609 reversed the increased CaMKKβ, adenosine 5'-monophosphate-activated protein kinase (AMPK), Beclin-1, and LC3B-II/LC3B-I protein expression levels and reduced mammalian target of rapamycin (mTOR) and P62 protein expression levels in Mo- and/or Cd-exposed cells. Collectively, the results confirmed that [Ca²⁺]_c overload resulted from PLC/IP₃/IP₃R pathway-mediated ER Ca²⁺ release, and then activated autophagy by the CaMKKβ/AMPK/mTOR pathway in Mo- and/or Cd-treated duck renal tubular epithelial cells.

Selenium Deficiency Induces Inflammatory Response and Decreased Antimicrobial Peptide Expression in Chicken Jejunum Through Oxidative Stress

Selenium deficiency can affect the level of selenoprotein in organs and tissues and cause inflammation. However, the mechanism of selenium deficiency on jejunal injury in chickens remains unclear. In this study, we established a selenium deficiency model in chickens by feeding a low selenium diet and observed ultrastructural and pathological changes in the jejunum. The expression levels of 25 selenoproteins, the levels of oxidative stress, tight junction (TJ) proteins, and antimicrobial peptides (AMP), as well as the expression levels of factors related to inflammatory signaling pathways, were examined in the intestine and analyzed using principal component analysis (PCA). The results of PCA and quantitative real-time PCR (qRT-PCR) showed that selenium deficiency mainly affected the expression of antioxidant selenoproteins in chicken jejunum, especially glutathione peroxidases, thioredoxin reductase, and iodothyronine deiodinase, thus weakening the antioxidant function in the intestine and inducing oxidative stress. We also found disruption of intestinal TJ structures, a significant reduction in TJ protein expression, and downregulation of antimicrobial peptide levels, suggesting that selenium deficiency led to damage of the intestinal barrier. In addition, a significant increase in inflammatory cell infiltration and expression of inflammatory factors was observed in the jejunum, indicating that selenium deficiency induces inflammatory injury. In conclusion, selenium deficiency downregulates antioxidant selenoproteins levels, induces oxidative stress, decreases intestinal AMP levels, and leads to inflammatory injury and disruption of the intestinal barrier in the jejunum. These results shed new light on the molecular mechanisms of intestinal damage caused by selenium deficiency.

Condensed Tannins Improved Immune Functions and Reduced Environmental Pollution of Captive Sichuan Black Goat Kids Under Cadmium Toxicity

To investigate the effects of condensed tannins (CT) on immune functions and nitrogen (N) emissions of captive Sichuan black goat kids under cadmium (Cd) toxicity, a total of 18 Sichuan black goat kids (2 months old, 9.6 ± 1.2 kg) were randomly used in this 30-day trial. The dietary treatments were (1) CON group, basic diet; (2) Cd group, basic diet + oral 10 mg Cd/kg·BW; and (3) CT group, Cd group + 400 mg/kg CT. Oral Cd supplementation significantly decreased the Cu and Fe contents in serums and livers of captive Sichuan black goat kids (P < 0.05), but adding CT in the Cd group increased the Fe and Mo contents and decreased the Cd content in serums and livers (P < 0.05). Additional CT supplementation in the Cd group extremely increased the activities of serum SOD, GSH-Px, and CAT (P < 0.05), and greatly decreased the serum MDA content (P < 0.05). The CT supplementation in the Cd group also extremely increased the concentrations of serum IgG, IgM, and IgA (P < 0.05), and greatly decreased the contents of IL-6, IL-1β, and TNF-α in serums (P < 0.05). Adding CT in the Cd group significantly increased the apparent digestibility of CP and EE and decreased the urinary nitrogen (UN) content (P < 0.05, Table 7). In conclusion, the application of additional CT improved antioxidant capacities and immune functions of captive black goats under Cd toxicity, then reduced the oxidative stress and toxic damage of Cd contamination. CT also improved the N digestibility and reduced the N emission, which was helpful to reduce environmental pollution.

Protective Effects of Astilbin Against Cadmium-Induced Apoptosis in Chicken Kidneys via Endoplasmic Reticulum Stress Signaling Pathway

Cadmium (Cd) can cause endoplasmic reticulum stress (ERS) and apoptosis in animals. The kidney is an organ seriously affected by Cd because it can accumulate metal ions. Astilbin (ASB) is a dihydroflavonol rhamnoside, which has an anti-renal injury effect. This study aimed to evaluate the protective effect of ASB on Cd-induced ERS and apoptosis in the chicken kidney. In this study, a total of 120 1-day-old chickens were randomly divided into 4 groups. Chickens were fed with a basic diet (Con group), ASB 40 mg/kg (ASB group), CdCl₂ 150 mg/kg + ASB 40 mg/kg (ASB/Cd group), and CdCl₂ 150 mg/kg (Cd group) for 90 days. The results showed that Cd exposure induced pathological and ultrastructural damages and apoptosis in chicken kidneys. Compared with the Con group, metallothionein (MT1/MT2) level, nitric oxide (NO) content, inducible nitric oxide synthase (iNOS) activity, ERS-related genes 78-kDa glucose-regulated protein (Grp78), protein kinase PKR-like endoplasmic reticulum kinase (Perk), activating transcription factor 4 (Atf4) and CAAT/enhancer-binding protein (C/EBP) homologous protein (Chop), and pro-apoptotic gene B-cell lymphoma 2 (Bcl-2)-associated X (Bax), caspase-12, caspase-9, caspase-3 expression levels, and apoptotic rate were significantly increased in the Cd group. The expression level of Bcl-2 was significantly decreased in the Cd group. ASB/Cd combined treatment significantly improves the damage of chicken kidneys by ameliorating Cd-induced kidney ERS and apoptosis. Cd can cause the disorder of the GRP78 signal axis, activate the PERK-ATF4-CHOP pathway, aggravate the structural damage and dysfunction of ER, and promote the apoptosis of chicken kidneys, while the above changes were significantly alleviated in the ASB/Cd group. The results showed that ASB antagonizes the negative effects of Cd and against Cd-induced apoptosis in chicken kidneys via ERS signaling pathway.

Melatonin administration alleviates 2,2,4,4-tetra-brominated diphenyl ether (PBDE-47)-induced necroptosis and secretion of inflammatory factors via miR-140-5p/TLR4/NF-κB axis in fish kidney cells

2,2,4,4-tetra-brominated diphenyl ether (PBDE-47)-the dominant homologue of polybrominated diphenyl ethers-is a toxic environmental pollutant in the aquatic environment that continuously exists and bioaccumulates in the aquatic food chain. In experimental disease models, melatonin (MEL) has been reported to attenuate necroptosis and inflammatory responses. To further explore the mechanism underlying PBDE-47 toxicity and the mitigative impact of MEL detoxification, in this study, fish kidney cell models of PBDE-47 poisoning and/or MEL treatment were developed. The Ctenopharyngodon idellus kidney (CIK) cell line was treated with PBDE-47 (100 μM) and/or MEL (60 μM) for 24 h. Experimental data suggest that PBDE-47 exposure resulted in the enhancement of cytoplasmic Ca²⁺ concentration, induction of calcium dysmetabolism, decrease in the miR-140-5p miRNA level, upregulation of Toll-like Receptor 4 (TLR4) and nuclear factor-kappaB (NF-κB), triggering of receptor interacting serine/threonine kinase-induced necroptosis, and NF-κB pathway mediated secretion of inflammatory factors in CIK cells. PBDE-47-induced CIK cell damage could be mitigated by MEL through the regulation of calcium channels and the restoration of disorders of the miR-140-5p/TLR4/NF-κB axis. Overall, MEL relieved PBDE-47-induced necroptosis and the secretion of inflammatory factors through the miR-140-5p/TLR4/NF-κB axis. These findings enrich the current understanding of the toxicological molecular mechanisms of the PBDE-47 as well as the detoxification mechanisms of the MEL.

Zinc Deficiency Aggravates Oxidative Stress Leading to Inflammation and Fibrosis in Lung of Mice

Zinc (Zn) is an essential trace element for the body. Studies have confirmed that Zn deficiency can cause oxidative stress. The purpose of the present study was designed to investigate the effect of Zn on fibrosis in lung of mice and its mechanism. Mice were fed with different Zn levels dietary, then we found that the Zn-deficient diet induced a decrease of Zn level in lung tissue. The results also revealed the alveolar structure hyperemia and an inflammatory exudated in the alveolar cavity. Moreover, immunohistochemical results showed that the expression of α-smooth muscle actin (α-SMA) increased. And the Sirius red staining indicated an increase in collagen with Zn deficiency. Furthermore, oxygen radicals (ROS) levels were significantly increased, and the antioxidants were significantly decreased. Meanwhile, inflammatory factors (TNF-α and IL-1β) were remarkably increased, and the ELISA results showed that collagen I, III, and IV and fibronectin (FN) were increased. In addition, the expressions of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) were detected by qPCR. The results showed that the expression of TIMPs was increased but the expression of MMPs was decreased. The results of the experiment in vitro were consistent with that in vivo. All the results indicated that Zn deficiency aggravated the oxidative stress response of lung tissue to induce inflammation, leading to fibrosis in lung.

Immunosuppression participated in complement activation-mediated inflammatory injury caused by 4-octylphenol via TLR7/IκBα/NF-κB pathway in common carp (Cyprinus carpio) gills

4-octylphenol (4-OP), a toxic estrogenic environmental pollutant, can threaten aquatic animal and human health. However, toxic effect of 4-OP on fish has not been reported. To investigate molecular mechanism of gill poisoning caused by 4-OP exposure, a carp 4-OP poisoning model was established, and then blood and gills were collected on day 60. The results demonstrated that gill was a target organ attacked by 4-OP, and exposure to 4-OP caused carp gill inflammatory injury. There were 1605 differentially expressed genes (DEGs, including 898 up-regulated DEGs and 707 down-regulated DEGs). KEGG and GO were used to further analyze obtained 1605 DEGs, indicating that complement activation, immune response, and inflammatory response participated in the mechanism of 4-OP-caused carp gill inflammatory injury. Our data at transcription level further revealed that 4-OP caused complement activation through triggering complement component 3a/complement component 3a receptor (C3a/C3aR) axis and complement component 5a/complement component 5a receptor 1 (C5a/C5aR1) axis, induced immunosuppression through the imbalances of T helper (Th) 1/Th2 cells and regulatory T (Treg)/Th17 cells, as well as caused inflammatory injury via toll like receptor 7/inhibitor kappa B alpha/nuclear factor-kappa B (TLR7/IκBα/NF-κB) pathway. Taken together, immunosuppression participated in complement activation-mediated inflammatory damage in carp gills after 4-OP treatment. The findings of this study will provide pioneering information and theoretical support for the mechanism of 4-OP poisoning, and will provide reference for the assessment of estrogenic environmental pollution risk.

Selenomethionine alleviates NF-κB-mediated inflammation in bovine mammary epithelial cells induced by Escherichia coli by enhancing autophagy

Autophagy is crucial for the maintenance of homeostasis under stimuli related to infection. Selenium (Se) plays variable roles in defence against infection and Selenomethionine (Se-Met) is a common Se supplementation. This study aimed to understand whether Se-Met could regulate the nuclear factor-kappa B (NF-κB) signaling pathway through autophagy. Mammary alveolar cell-T (MAC-T) was challenged with Escherichia coli (E. coli). Western blotting and real-time quantitative PCR (RT-qPCR) were used to detect the protein expression and mRNA expression of cytokines. Immunofluorescence assays were performed to observe the expression of intracellular LC3. The results showed that E. coli inhibited autophagy by decreasing the LC3-Ⅱ protein levels, and the Atg5 and Beclin1 protein levels were increased after 4 h. Infection also decreased the number of LC3 puncta. E. coli increased the phosphorylation of p65 and IκBα protein. Concomitantly, the levels of interleukin (IL)-1β, IL-6, IL-8 and tumour necrosis factor (TNF)-α mRNA increased at 3 and 4 h post-infection. We further explored the regulatory role of autophagy on NF-κB-mediated inflammation with autophagy modulators and shAtg5. The results indicated that the autophagy activator reduced the phosphorylation of p65 and IκBα and the mRNA expression of IL-1β, IL-6, IL-8 and TNF-α. Additionally, activating autophagy weakened the adhesion to MAC-T of E. coli. Autophagy inhibitors exacerbated NF-κB-mediated inflammation and strengthened the adhesion of E. coli to cells. We then examined the effects of Se-Met on NF-κB-mediated inflammation through autophagy. The data suggested that Se-Met enhanced LC3-II expression, inhibited the E. coli-induced phosphorylation of p65 and IκBα, and suppressed the adhesion ability of E. coli to MAC-T and that the effects of Se-Met in attenuating NF-κB-mediated inflammation were partially blocked by an autophagy inhibitor. In summary, Se-Met alleviated NF-κB-mediated inflammation induced by E. coli by enhancing autophagy in bovine mammary epithelial cells.

The protective effect of selenoprotein M on non-alcoholic fatty liver disease: the role of the AMPKα1-MFN2 pathway and Parkin mitophagy

Non-alcoholic fatty liver disease (NAFLD) is related to a dysregulation of mitophagy, a process that is not fully understood. Parkin-related mitophagy can sustain mitochondrial homeostasis and hepatocyte viability. Herein, we report that selenoprotein M (SELENOM) plays a central role in maintaining mitophagy in high-fat diet (HFD)-mediated NAFLD. We show that SELENOM was significantly downregulated in the liver of HFD-fed mice. SELENOM deletion aggravated HFD-mediated hepatic steatosis, inflammation, and fibrosis; accompanied by enhanced fatty acid oxidation and oxidative stress in the liver. Molecular analyses show that lipotoxicity was related to increased mitochondrial apoptosis as evidenced by enhanced mitochondrial ROS production, and attenuation of mitochondrial potential in the liver of HFD-fed SELENOM-/- mice. Additionally, SELENOM deletion reduced mitophagy and aggravated hepatic injury in NAFLD. Mechanistically, SELENOM overexpression activated Parkin-mediated mitophagy to reduce mitochondrial apoptosis and remove HFD-damaged mitochondria. We further found that SELENOM regulates Parkin expression via the AMPKα1-MFN2 pathway; blockade of AMPKα1 prevented SELENOM activation of Parkin-mediated mitophagy. Our work identified SELENOM downregulation as a possible explanation for the defective mitophagy in NAFLD. Thus, targeting SELENOM may be potential new therapeutic modalities for NAFLD treatment.

Cadmium induces apoptosis and autophagy in swine small intestine by downregulating the PI3K/Akt pathway

Cadmium (Cd) is an environmental contaminant, which is potentially toxic. It is well known that Cd can accumulate in the liver and kidney and cause serious damage. However, few studies have investigated the mechanism of intestinal damage induced by Cd in swine. Here, we established Cd poisoning models in vivo and in vitro to explore the mechanism of intestinal injury induced by Cd in swine. The morphology of intestinal tissue cells was observed by TUNEL staining and electron microscopy, and the morphology of IPEC-J2 cells was observed by flow cytometry, Hoechst staining, and MDC staining. Cell morphological observations revealed that Cd treatment induced ileal apoptosis and autophagy. The effects of Cd on the PI3K/Akt pathway, as well as on apoptosis and autophagy-related protein expression in intestinal cells, were analyzed by western blot (WB) and the expression of mRNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that Cd induced autophagy by increasing the levels of autophagy markers Beclin1, Autophagy-associated gene 5 (ATG5), Autophagy-associated gene 16 (ATG16), and Microtubule-associated protein light chains 3-2 (LC3-II), and by reducing the expression levels of Mechanistic target of rapamycin kinase (mTOR) and Microtubule-associated protein light chains 3-1 (LC3-I). Cell apoptosis was induced by increasing the expression of apoptosis markers Bcl-2 associated X protein (Bax), Cysteinyl aspartate specific proteinase 9 (Caspase9), cleaved Caspase9, Cysteinyl aspartate specific proteinase 3 (Caspase3), and cleaved Caspase3, and by reducing the expression of B cell lymphoma/leukemia 2 (Bcl-2). At the same time, Cd decreased the expression of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and their phosphorylation. We treated IPEC-J2 cells with the PI3K activator 740Y-P and analyzed the morphological changes as well as autophagy and apoptosis-related gene expression. The results showed that 740Y-P could reduce apoptosis and autophagy induced by Cd. In conclusion, our findings suggest that Cd induces intestinal apoptosis and autophagy in swine by inactivating the PI3K/Akt signaling pathway.

A new discovery of polystyrene microplastics toxicity: The injury difference on bladder epithelium of mice is correlated with the size of exposed particles

Microplastics (MPs), as widespread hazardous substances in the environment, can cause potential adverse effects on biological health. However, reports on the toxic effects of different diameters MPs on urinary system are limited. Here, we investigated the types and mechanisms of damage to mice bladder epithelial cells treated with diameter (1-10 μm and 50-100 μm) polystyrene microplastics (PS-MPs). The results showed that exposure to PS-MPs of both diameters resulted in necroptosis and inflammation to bladder epithelium. However, 1-10 μm PS-MPs posed more severe necroptosis and 50-100 μm PS-MPs led to a higher degree of inflammatory injury at the same exposure concentration. Mechanistically, PS-MPs were found to induce necroptosis as well as p-NFκB-mediated inflammation by triggering oxidative stress and excessive release of reactive oxygen species (ROS). Furthermore, N-Acetyl-l-cysteine (NAC) attenuated the toxic effects of PS-MPs on bladder epithelial cells. In conclusion, our study demonstrated for the first time that PS-MPs caused necroptosis and inflammation in mice bladders tissues, and the difference of injury correlates with the size of PS-MPs particles.

Melatonin ameliorates nickel induced autophagy in mouse brain: diminution of oxidative stress

Nickel（Ni) is a neurotoxic environmental pollutant. Oxidative stress is thought to be the main mechanism behind the development of Ni neurotoxicity. Melatonin (Mt) has significant efficacy as an antioxidant. In this paper, we investigated the damage that Ni causes to the autophagy of the nervous system. Furthermore, Mt has can intervene upon the damage caused by Ni, which can protect the nervous system. Herein, we randomly divided 80 8-week-old male wild-type C57BL/6N mice into four groups, including the C group, Ni group, Mt group, and Mt+Ni group. Ni was gavaged at a concentration of 10mg/kg, while was Mt was administered at a concentration of 2mg/kg for 21 days at 0.1ml/10g body weight of the mice. Histopathological and ultrastructural observations demonstrated altered states, such as neuronal atrophy, as well as typical autophagic features in the Ni group. Mt was able to intervene effectively in Ni-induced neurotoxicity. The antioxidant capacity assay also demonstrated that Ni can lead to a large amount of reactive oxygen species (ROS) production within the mouse brain. Furthermore, the same Mt was effective at reducing ROS production. In order to further illustrate this point, we added the broad-spectrum phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 to NS20Y cells. The presence of inhibitors effectively demonstrates that, within the PI3K/AKT/mTOR pathway, autophagy occurs. In conclusion, these data suggest that Ni causes oxidative stress damage and induces autophagy within the mouse brain by inhibiting the PI3K/AKT/mTOR pathway, and that Mt can effectively alleviate the oxidative stress caused by Ni, and reducing Ni induces autophagy in the mouse brain through the PI3K/AKT/mTOR pathway.

Schisandrin B Induced ROS-Mediated Autophagy and Th1/Th2 Imbalance via Selenoproteins in Hepa1-6 Cells

Schisandrin B (Sch B) is well-known for its antitumor effect; however, its underlying mechanism remains confusing. Our study aimed to investigate the role of selenoproteins in Sch B-induced autophagy and Th1/Th2 imbalance in Hepa1-6 cells. Hepa1-6 cells were chosen to explore the antitumor mechanism and were treated with 0, 25, 50, and 100 μM of Sch B for 24 h, respectively. We detected the inhibition rate of proliferation, transmission electron microscopy (TEM), monodansylcadaverine (MDC) staining, reactive oxygen species (ROS) level and oxidative stress-related indicators, autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein mRNA expression. Moreover, the heat map, principal component analysis (PCA), and correlation analysis were used for further bioinformatics analysis. The results revealed that Sch B exhibited well-inhibited effects on Hepa1-6 cells. Subsequently, under Sch B treatment, typical autophagy characteristics were increasingly apparent, and the level of punctate MDC staining enhanced and regulated the autophagy-related genes. Overall, Sch B induced autophagy in Hepa1-6 cells. In addition, Sch B-promoted ROS accumulation eventually triggered autophagy initiation. Results of Th1 and Th2 cytokine mRNA expression indicated that Th1/Th2 immune imbalance was observed by Sch B treatment in Hepa1-6 cells. Intriguingly, Sch B downregulated the majority of selenoprotein expression. Also, the heat map results observed significant variation of autophagy-related genes, related Th1/Th2 cytokines, and selenoprotein expression in response to Sch B treatment. PCA outcome suggested the key role of Txnrd1, Txnrd3, Selp, GPX2, Dio3, and Selr with its potential interactions in ROS-mediated autophagy and Th1/Th2 imbalance of Hepa1-6 cells. In conclusion, Sch B induced ROS-mediated autophagy and Th1/Th2 imbalance in Hepa1-6 cells. More importantly, the majority of selenoproteins were intimately involved in the process of autophagy and Th1/Th2 imbalance, Txnrd3, Selp, GPX2, Dio3, and Selr had considerable impacts on the process.

Individual and mixtures of metal exposures in associations with biomarkers of oxidative stress and global DNA methylation among pregnant women

BACKGROUND

Prenatal exposure to metals has been linked with adverse pregnancy outcomes. Oxidative stress and epigenetic changes are potential mechanisms of action.

OBJECTIVES

We aimed to examine the associations of individual and mixtures of metal exposures with oxidative stress and DNA methylation among pregnant women.

METHODS

We measured a panel of 16 metals and 3 oxidative stress biomarkers including 8-hydroxydeoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) and 8-isoprostaglandin F2α (8-isoPGF2α) in urine from 113 pregnant women in a Chinese cohort. Biomarkers of global DNA methylation including Alu and long interspersed nucleotide element-1 (LINE-1) in cord blood were measured. Multivariable linear regression and Bayesian kernel machine regression (BKMR) models were separately applied to estimate the associations between individual and mixtures of metal exposures and biomarkers of oxidative stress and global DNA methylation.

RESULTS

In single-metal analyses, we observed positive associations between 11 metals [arsenic (As), cadmium (Cd), thallium (Tl), barium (Ba), nickel (Ni), vanadium (V), cobalt (Co), zinc (Zn), copper (Cu), selenium (Se) and molybdenum (Mo)] and at least one of oxidative stress biomarkers (all FDR-adjusted P-values < 0.05). In mixture analyses, we found positive overall associations of metal mixtures with 8-OHdG and 8-isoPGF2α, and Se was the most important predictor. There was no evidence on associations of urinary metals as individual chemicals and mixtures with Alu and LINE-1 methylation.

CONCLUSION

Urinary metals as individual chemicals and mixtures were associated with increased oxidative stress, especially Se.

Melatonin relieves 2,2,4,4-tetrabromodiphenyl ether (BDE-47)-induced apoptosis and mitochondrial dysfunction through the AMPK-Sirt1-PGC-1α axis in fish kidney cells (CIK)

Polybrominated diphenyl ethers (PBDEs) exist in aquatic environments with nephrotoxicity to non-target aquatic species. Melatonin (MT) exhibits an inhibitory effect of oxidative stress and apoptosis in various diseases. 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) is the main homolog of PBDE samples. Therefore, we investigated the toxic mechanism of BDE-47 and the alleviation effect of MT, the ctenopharyngodon idellus kidney (CIK) cells were treated with BDE-47 (100 μM) and/or MT (60 μM) for 24 h. Firstly, BDE-47 exposure could inhibit oxidative stress-related antioxidant enzymes (T-AOC, SOD, CAT and GPx) and increase the content of malondialdehyde (MDA) to cause oxidative stress. Secondly, BDE-47 enhanced mitochondrial division and inhibited fusion to induce mitochondrial membrane potential in CIK cells. BDE-47 enhanced the mRNA and protein levels of mitochondrial-pathway apoptosis related genes (Cas 3, Cyt-c, and BAX). Thirdly, BDE-47 treatment decreased the expression levels of mitochondrial-related regulatory factors AMPK-Sirt1-PGC-1α signal pathway. Intriguingly, BDE-47-induced oxidative stress, mitochondrial pathway apoptosis and mitochondrial dynamics disorder could be alleviated by MT treatment. Overall, we concluded that MT could relieve BDE-47-induced oxidative stress, mitochondrial dysfunction and apoptosis through the AMPK-Sirt1-PGC-1α axis. These results enrich the mechanisms of BDE-47 poisoning and reveal that MT treatment may be a potential strategy for solving BDE-47 poisoning.

Albicanol modulates oxidative stress and the p53 axis to suppress profenofos induced genotoxicity in grass carp hepatocytes

The organophosphorus pesticide profenofos (PFF) is widely used as an environmental contaminant, and it can remain in water bodies causing serious harm to aquatic organisms. Albicanol is a sesquiterpenoid with potent antioxidant and antagonistic activities against heavy metal toxicity. However, the mechanism of PFF induced genotoxicity in fish hepatocytes and the role Albicanol can play in this process are unknown. In this study, the model was established by treating grass carp hepatocytes with PFF (150 μM) and/or Albicanol (5 × 10^-5 μg mL^-1) for 24 h. The results showed that PFF exposure arrested L8824 cells in the G1-S phase. PFF caused the increase of MDA level in L8824 cells, while the decrease of SOD, CAT and T-AOC levels caused oxidative stress. Elevated levels of γH2AX, tail moment, tail length, % DNA and 8-OHdG indicated that PFF caused DNA damage in L8824 cells. PFF inhibited the expression levels of cell cycle related regulatory genes (cyclin A, cyclin D, cyclin E, CDK2 and CDK4) by upregulating p53/p21 genes and activating the p53 signaling pathway. Albicanol was used to significantly reduce the above effects caused by PFF exposure on hepatocytes in grass carp. Albicanol could reduce the increase in the proportion of cells in the G1-S phase caused by PFF. In summary, Albicanol could inhibit the genotoxicity of L8824 cells resulted from PFF exposure by decreasing oxidative stress and the p53 pathway.

Lycopene attenuates oxidative stress, inflammation, and apoptosis by modulating Nrf2/NF-κB balance in sulfamethoxazole-induced neurotoxicity in grass carp (Ctenopharyngodon Idella)

All drugs that can penetrate the blood-brain barrier (BBB) may lead to mental state changes, including the widely used anti-infective drug sulfamethoxazole (SMZ). Herein, we investigated whether lycopene (LYC) could ameliorate SMZ-induced brain injury and the postulated mechanisms involved. A total of 120 grass carps were exposed under SMZ (0.3 μg/L, waterborne) or LYC (10 mg/kg fish weight, diet) or their combination for 30 days. Firstly, brain injury induced by SMZ exposure was suggested by the damage of BBB (decreases of Claudins, Occludin and Zonula Occludens), and the decrease of neurotransmitter activity (AChE). Through inducing oxidative stress (elevations of malondialdehyde and 8-hydroxy-2 deoxyguanosine, inhibition of glutathione), SMZ increased the intra-nuclear level of NF-κB and its target genes (TNF-α and interleukins), creating an inflammatory microenvironment. As a positive feed-back mechanism, apoptosis begins with activation of pro-death proteins (Bax/Bcl-2) and activation of caspases (caspase-9 and caspase-3). Meanwhile, a compensatory upregulation of constitutive Nrf2 and its downstream antioxidative gene expression (NAD(P)H Quinone Dehydrogenase 1 and Heme oxygenase 1) and accelerated autophagy (increases of autophagy-related genes and p62 inhibition) were activated as a defense mechanism. Intriguingly, under SMZ stress, LYC co-administration decreased NF-κB/apoptosis cascades and restored Nrf2/autophagy levels. The neuroprotective roles of LYC make this natural compound a valuable agent for prevention SMZ stress in environment. This study suggests that LYC might be developed as a potential candidate for alleviating environmental SMZ stress in aquaculture.

Molybdenum and Cadmium Co-induce Mitochondrial Quality Control Disorder via FUNDC1-Mediated Mitophagy in Sheep Kidney

Molybdenum (Mo), fundamental trace mineral for animals and plants, but undue Mo damages animal health. Cadmium (Cd) is a toxic heavy metal that exists in the environment. Nevertheless, the mechanism of Mo and Cd on mitochondrial quality control are still indistinct. The objective of this research was to explore the effects of mitophagy on mitochondrial quality control via the FUNDC1-mediated by Mo and Cd in sheep kidney. Forty-eight 2-month-old sheep were stochastically divided into four groups, as shown below: control group, Mo [45 mg/kg body weight (BW)] group, Cd (1 mg/kg BW) group and Mo (45 mg/kg BW)+Cd (1 mg/kg BW) group, with 50 days feed technique. The results showed that Mo or/and Cd attract an unbalance of trace minerals and vacuoles and granular degeneration of renal tubular epithelial cells, and increase the number of mitophagosomes and vacuole-mitochondria and LC3 puncta and MDA and H2O2 contents, and decrease ATP content in the kidney. Moreover, Mo or/and Cd treatment could upregulate the mRNA levels of FUNDC1, LC3A, LC3B, PGAM5, DRP1, FIS1 and MFF, and the protein levels of FUNDC1, p-FUNDC1, LC3II/LC3I, DRP1, MFF and FIS1, downregulate the mRNA levels of MFN1, MFN2, OPA1, PGC-1α, SIRT1, SIRT3, FOXO1 and FOXO3, and the protein levels of MFN1, MFN2, OPA1 and PGC-1α. Notably, variations of above-mentioned factors in Mo and Cd group were more obvious than in Mo or Cd groups. Taken together, these results displayed that Mo and Cd co-treatment might induce mitochondrial quality control disorder via FUNDC1-mediated mitophagy in sheep kidney.

Hyperoside Attenuates Zearalenone-induced spleen injury by suppressing oxidative stress and inhibiting apoptosis in mice

Zearalenone (ZEA) is a ubiquitous mycotoxin contaminant that causes immune toxicity, apoptosis, and oxidative stress in animals. Hyperoside (Hyp) is a flavonol glycoside compound with antioxidant and anti-apoptotic properties. However, the potential of Hyp to prevent ZEA-induced spleen injury remains unknown. To evaluate the chemoprotective effect of Hyp against ZEA-induced spleen injury, 60 male Kunming mice were randomly assigned into five groups. The first two groups were orally treated with ZEA (40 mg/kg) for 30 days, and combined with Hyp (0, 100 mg/kg) treatment. The other three groups are orally treated with normal saline, olive oil, or Hyp (100 mg/kg) for 30 days. Hyperoside had an inhibitory effect against ZEA-induced spleen lesions. In addition, Hyp significantly increased the activity of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT)], the total antioxidant capacity (T-AOC), and significantly reduced the malondialdehyde (MDA) content reducing ZEA-induced oxidative stress in the spleen. Moreover, the translation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target genes (CAT, NQO1, SOD1, GSS, GCLM, and GCLC) were ameliorated using co-therapy with Hyp before treatment with ZEA. Hyperoside also significantly inhibited the translation and expression of apoptotic genes (caspase3, casepase9, Bax, Bcl-2) and the production of apoptotic bodies induced by ZEA in the spleen. In conclusion, the findings revealed that Hyp inhibited ZEA-induced spleen injury through its antioxidant and anti-apoptotic effects. Thus, it provides a new treatment option for immune system diseases caused by ZEA.

MiR-144-3p targets STC1 to activate PI3K/AKT pathway to induce cell apoptosis and cell cycle arrest in selenium deficiency broilers

Selenium (Se) is an indispensable trace element in vertebrate. Se deficiency can damage the immune system. Studies have shown that Se deficiency can cause immune organ damage by regulating the expression of microRNA. Bursa of Fabricius is a special immune organ in poultry. In order to explore the mechanism of bursa of Fabricius injury caused by Se deficiency and the role of miRNA in this process. Firstly, we established the Se deficient model of broilers in vivo and found that Se deficiency could induce apoptosis and cell cycle arrest of bursa of Fabricius cells through Phosphoinositide 3-kinase (PI3K)/Protein Kinase B (AKT) pathway. Secondly, we inferred miRNA (miR-144-3p) and target gene Stanniocalcin 1 (STC1) that may regulate PI3K/AKT pathway through biological analysis system, and further predicted and determined the targeting relationship between them through dual luciferase, it was found that miR-144-3p was highly expressed in the process of cell apoptosis and cell cycle arrest induced by Se deficiency. Finally, in order to further understand whether miR-144-3p/STC1 axis is involved in the process, miR-144-3p knockdown and overexpression experiments were carried out, it was found that miR-144-3p inhibitor can reduce the occurrence of cell apoptosis and cell cycle arrest. In conclusion, Se deficiency can induce apoptosis and cell cycle arrest of bursa of Fabricius in Broilers by up regulating miR-144-3p targeting STC1 and activating PI3K/AKT pathway, leading to injury of bursa of Fabricius in broilers.