Targeting JAK2/STAT3, NLRP3/Caspase-1, and PK2/PKR2 Pathways with Arbutin Ameliorates Lead Acetate-Induced Testicular Injury in Rats

The reproductive system of males is adversely impacted by lead (Pb), a toxic heavy metal. The present study examined arbutin, a promising hydroquinone glycoside, for its potential ameliorative impact against Pb-induced testicular impairment in rats. The testicular injury was induced by the intraperitoneal administration of Pb acetate (20 mg/kg/day) for 10 consecutive days. Thirty-six rats were divided into six experimental groups (n = 6 per group): control, control treated with oral arbutin (250 mg/kg), control treated with intraperitoneal arbutin (75 mg/kg), untreated Pb, Pb treated with oral arbutin, and Pb treated with intraperitoneal arbutin. The treatments were administered daily for 10 days. Arbutin was administered by the oral and intraperitoneal routes to compare the efficacy of both routes in mitigating Pb acetate-induced testicular dysfunction. The current data revealed that both oral and intraperitoneal administration of arbutin significantly enhanced serum testosterone and sperm count/motility, indicating the amelioration of testicular dysfunction. In tandem, both routes lowered testicular histopathological aberrations and Johnsen's damage scores. These favorable outcomes were driven by dampening testicular oxidative stress, evidenced by lowered lipid peroxidation and increased glutathione and catalase antioxidants. Moreover, arbutin lowered testicular p-JAK2 and p-STAT3 levels, confirming the inhibition of the JAK2/STAT3 pro-inflammatory pathway. In tandem, arbutin suppressed the testicular NLRP3/caspase-1/NF-B axis and augmented the cytoprotective PK2/PKR2 pathway. Notably, intraperitoneal arbutin at a lower dose prompted a more pronounced mitigation of Pb-induced testicular dysfunction compared to oral administration. In conclusion, arbutin ameliorates Pb-evoked testicular damage by stimulating testicular antioxidants and the PK2/PKR2 pathway and inhibiting the JAK2/STAT3 and NLRP3/caspase-1 pro-inflammatory pathways. Hence, arbutin may be used as an adjunct agent for mitigating Pb-induced testicular impairment.

Subcutaneous administration of Stattic alleviates neuropathic pain by relieving inflammation in a mouse model of postherpetic neuralgia

Stattic, a commercial inhibitor of STAT3, can drive the development of neuropathic pain. Exploring the connection between Stattic and JAK1/STAT3 signaling may facilitate the understanding of neuropathic pain caused by postherpetic neuralgia (PHN). In the current study, as crucial regulators of inflammation, STAT3 and its associated JAK1/STAT3 pathway were found to be upregulated and activated in the L4-L6 dorsal root ganglion (DRG) of mice in response to resiniferatoxin (RTX)-induced PHN, while subcutaneous administration of Stattic was found to downregulate STAT3 expression and phosphorylation in a PHN model. Stattic administration further attenuated hypersensitivity to mechanical and thermal stimuli in PHN mice, and alleviated inflammation and cell death in the L4-L6 DRG of mice. Overexpression of STAT3 via microinjection of a lentiviral-STAT3 overexpression vector reversed the abnormal decrease of STAT3 at both the mRNA and protein levels in the L4-6 DRGs of PHN mice and significantly promoted hypersensitivity to mechanical stimuli in the mice. Collectively, we found that subcutaneous static administration alleviated RTX-induced neuropathic pain by deactivating JAK1/STAT3 in mice.

Fusarium mycotoxins: The major food contaminants

Mycotoxins, which are secondary metabolites produced by toxicogenic fungi, are natural food toxins that cause acute and chronic adverse reactions in humans and animals. The genus Fusarium is one of three major genera of mycotoxin-producing fungi. Trichothecenes, fumonisins, and zearalenone are the major Fusarium mycotoxins that occur worldwide. Fusarium mycotoxins have the potential to infiltrate the human food chain via contamination during crop production and food processing, eventually threatening human health. The occurrence and development of Fusarium mycotoxin contamination will change with climate change, especially with variations in temperature, precipitation, and carbon dioxide concentration. To address these challenges, researchers have built a series of effective models to forecast the occurrence of Fusarium mycotoxins and provide guidance for crop production. Fusarium mycotoxins frequently exist in food products at extremely low levels, thus necessitating the development of highly sensitive and reliable detection techniques. Numerous successful detection methods have been developed to meet the requirements of various situations, and an increasing number of methods are moving toward high-throughput features. Although Fusarium mycotoxins cannot be completely eliminated, numerous agronomic, chemical, physical, and biological methods can lower Fusarium mycotoxin contamination to safe levels during the preharvest and postharvest stages. These theoretical innovations and technological advances have the potential to facilitate the development of comprehensive strategies for effectively managing Fusarium mycotoxin contamination in the future.

Prmt7 regulates the JAK/STAT/Socs3 signaling pathway in postmenopausal cardiomyopathy

Protein arginine methyltransferases (PRMTs) modulate diverse cellular processes, including stress responses. The present study explored the role of Prmt7 in protecting against menopause-associated cardiomyopathy. Mice with cardiac-specific Prmt7 ablation (cKO) exhibited sex-specific cardiomyopathy. Male cKO mice exhibited impaired cardiac function, myocardial hypertrophy, and interstitial fibrosis associated with increased oxidative stress. Interestingly, female cKO mice predominantly exhibited comparable phenotypes only after menopause or ovariectomy (OVX). Prmt7 inhibition in cardiomyocytes exacerbated doxorubicin (DOX)-induced oxidative stress and DNA double-strand breaks, along with apoptosis-related protein expression. Treatment with 17β-estradiol (E2) attenuated the DOX-induced decrease in Prmt7 expression in cardiomyocytes, and Prmt7 depletion abrogated the protective effect of E2 against DOX-induced cardiotoxicity. Transcriptome analysis of ovariectomized wild-type (WT) or cKO hearts and mechanical analysis of Prmt7-deficient cardiomyocytes demonstrated that Prmt7 is required for the control of the JAK/STAT signaling pathway by regulating the expression of suppressor of cytokine signaling 3 (Socs3), which is a negative feedback inhibitor of the JAK/STAT signaling pathway. These data indicate that Prmt7 has a sex-specific cardioprotective effect by regulating the JAK/STAT signaling pathway and, ultimately, may be a potential therapeutic tool for heart failure treatment depending on sex.

Galantamine mitigates testicular injury and disturbed spermatogenesis in adjuvant arthritic rats via modulating apoptosis, inflammatory signals, and IL-6/JAK/STAT3/SOCS3 signaling

Rheumatoid arthritis (RA) affects the joints and the endocrine system via persistent immune system activation. RA patients have a higher frequency of testicular dysfunction, impotence, and decreased libido. This investigation aimed to evaluate the efficacy of galantamine (GAL) on testicular injury secondary to RA. Rats were allocated into four groups: control, GAL (2 mg/kg/day, p.o), CFA (0.3 mg/kg, s.c), and CFA + GAL. Testicular injury indicators, such as testosterone level, sperm count, and gonadosomatic index, were evaluated. Inflammatory indicators, such as interleukin-6 (IL-6), p-Nuclear factor kappa B (NF-κB p65), and anti-inflammatory cytokine interleukin-10 (IL-10), were assessed. Cleaved caspase-3 expression was immunohistochemically investigated. Protein expressions of Janus kinase (JAK), signal transducers and activators of transcription (STAT3), and Suppressors of Cytokine Signaling 3 (SOCS3) were examined by Western blot analysis. Results show that serum testosterone, sperm count, and gonadosomatic index were increased significantly by GAL. Additionally, GAL significantly diminished testicular IL-6 while improved IL-10 expression relative to CFA group. Furthermore, GAL attenuated testicular histopathological abnormalities by CFA and downregulated cleaved caspase-3 and NF-κB p65 expressions. It also downregulated JAK/STAT3 cascade with SOCS3 upregulation. In conclusion, GAL has potential protective effects on testicular damage secondary to RA via counteracting testicular inflammation, apoptosis, and inhibiting IL-6/JAK/STAT3/SOCS3 signaling.

Deoxynivalenol induces endoplasmic reticulum stress-associated apoptosis via the IRE1/JNK/CHOP pathway in porcine alveolar macrophage 3D4/21 cells

The interplay between cell apoptosis and endoplasmic reticulum (ER) stress has garnered increasing attention. Nevertheless, the precise involvement of the unfolded protein response (UPR) signaling in the apoptosis of porcine macrophage cells induced by Deoxynivalenol (DON) remains enigmatic. In this study, we revealed that exposure to 2 μM DON resulted in a substantial decline in cell viability, concomitant with the initiation of cell apoptosis and the halting of the G1 phase cell cycle in the porcine alveolar macrophage line 3D4/21. Transcriptomic analysis of DON-exposed cells showed distinct expression patterns in 3104 genes, with notable upregulation of ER stress-related genes, including IRE1, CHOP, XBP1 and JNK. Our subsequent validation via qPCR and Western blot analyses confirmed the attenuation of GRP78 and BCL-2, coupled with the upregulation of IRE1, CHOP, JNK, p-JNK, and Bax in DON-induced cells, indicating the instigation of ER stress-associated apoptosis by DON. The addition of 5 mM 4-phenylbutyric acid (4-PBA), an ER stress inhibitor, decreased levels of CHOP, IRE1, JNK, p-JNK, and Bax, while increasing levels of GRP78 and Bcl-2, suggesting that 4-PBA alleviated DON-induced ER stress and apoptosis. Overall, our findings provide new insights into DON-induced ER stress via the IRE1/JNK/CHOP pathway, leading to subsequent cellular apoptosis.

Deoxynivalenol: Emerging Toxic Mechanisms and Control Strategies, Current and Future Perspectives

Deoxynivalenol (DON) is the most frequently present mycotoxin contaminant in food and feed, causing a variety of toxic effects in humans and animals. Currently, a series of mechanisms involved in DON toxicity have been identified. In addition to the activation of oxidative stress and the MAPK signaling pathway, DON can activate hypoxia-inducible factor-1α, which further regulates reactive oxygen species production and cancer cell apoptosis. Noncoding RNA and signaling pathways including Wnt/β-catenin, FOXO, and TLR4/NF-κB also participate in DON toxicity. The intestinal microbiota and the brain-gut axis play a crucial role in DON-induced growth inhibition. In view of the synergistic toxic effect of DON and other mycotoxins, strategies to detect DON and control it biologically and the development of enzymes for the biodegradation of various mycotoxins and their introduction in the market are the current and future research hotspots.

Mycotoxins Have a Potential of Inducing Cell Senescence: A New Understanding of Mycotoxin Immunotoxicity

Mycotoxins result in immune dysfunction and cause immune diseases in animals and humans. However, the mechanisms of immunotoxicity involved in mycotoxins have not been fully explored, and emerging evidence suggests that these toxins may promote their immunotoxicity via cellular senescence. Mycotoxins induce cell senescence after DNA damage, and activate signaling via the NF-κB and JNK pathways to promote the secretion of senescence-associated secretory phenotype (SASP) cytokines including IL-6, IL-8, and TNF-α. DNA damage can also over-activate or cleave poly (ADP-ribose) polymerase-1 (PARP-1), increase the expression of cell cycle inhibitory proteins p21, and p53, and induce cell cycle arrest and then senescence. These senescent cells further down-regulate proliferation-related genes and overexpress inflammatory factors resulting in chronic inflammation and eventual immune exhaustion. Here we review the underlying mechanisms by which mycotoxins trigger cell senescence and the potential roles of SASP and PARP in these pathways. This work will help to further understand the mechanisms of immunotoxicity involved in mycotoxins.

Deoxynivalenol hijacks the pathway of Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT-3) to drive caspase-3-mediated apoptosis in intestinal porcine epithelial cells

Deoxynivalenol (DON) can easily injure the intestinal tract, which represents the first barrier against food contaminants. The intestinal toxicity induced by DON was mainly focused on mitogen-activated protein kinase (MAPK) activation, however, the underlying mechanisms by which DON triggers apoptosis by other pathways remain poorly understood. In this study, the Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT-3) pathway was proposed to regulate the intrinsic apoptosis induced by DON and thoroughly investigated in intestinal porcine epithelial cells (IPEC-J2). First, DON was found to be able to efficiently inhibit cell viability and increase the release of lactate dehydrogenase. It could also enhance the activity of the cleaved caspase-3 in a time-dependent manner, accompanied by a loss of mitochondrial membrane potential and an up-regulation of the apoptosis rate. Then, the expression of genes associated with inflammation and apoptosis were investigated. DON increased the expression of IL-6, IL-1β, TNF-α, SOCS3 and Bax, but decreased the expression of Bcl-2 and Bcl-xL. Moreover, we discovered that DON robustly inhibited STAT-3 activity together with the down-regulation of JAK2, Bcl-2 and Bcl-xL, paralleling the increase in p38 phosphorylation. Furthermore, a pharmacological activation of JAK2/STAT-3 alleviated DON induced-apoptosis. Concurrent with the apoptotic pathway, during the initial exposure to DON (first 4 h), a survival pathway involving phosphorylated Erk1/2, Akt, and FoxO1 was also observed. Thus, apoptosis induced by DON was Janus faced: although the survival pathway was activated, the DON-induced apoptotic JAK2/STAT-3/caspase-3 pathway dominated, leading to an imbalance in cell homeostasis. This study provides a novel avenue to comprehensively reveal the pathological mechanisms of DON-induced intestinal disorders, which is promising for future applications to other contaminants in food and feed.

A Focused Review on Molecular Signalling Mechanisms of Ginsenosides Anti-Lung Cancer and Anti-inflammatory Activities

BACKGROUND

Ginseng (Panax ginseng Meyer) is a cultivated medicinal herb that has been widely available in the Asian region since the last century. Ginseng root is used worldwide in Oriental medicine. Currently, the global mortality and infection rates for lung cancer and inflammation are significantly increasing. Therefore, various preventative methods related to the activity of ginsenosides have been used for lung cancer as well as inflammation.

METHODS

Web-based searches were performed on Web of Science, Springer, PubMed, and Scopus. A cancer statistical analysis was also conducted to show the current ratio of affected cases and death from lung cancer around the world.

RESULTS

Ginsenosides regulate the enzymes that participate in tumor growth and migration, such as nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (p38 MAPK), c-Jun N-terminal kinase (JNK), extracellular signalregulated kinases 1/2 (ERK1/2), the gelatinase network metalloproteinase-2 (MMP-2/9) and activator protein 1 (AP-1). In addition, ginsenosides also possess anti-inflammatory effects by inhibiting the formation of proinflammatory cytokines (tumor necrosis factor-α) (TNF-α) and interleukin-1β (IL-1β) and controlling the activities of inflammatory signalling pathways, such as NF-κB, Janus kinase2/signal transducer, and activator of transcription 3 (Jak2/Stat3).

CONCLUSION

In several in vitro and in vivo models, P. ginseng showed potential beneficial effects in lung cancer and inflammation treatment. In this review, we provide a detailed and up-to-date summary of research evidence for antilung cancer and anti-inflammatory protective effects of ginsenosides and their potential molecular mechanisms.

1,25-Dihydroxyvitamin D3 Negatively Regulates the Inflammatory Response to Porcine Epidemic Diarrhea Virus Infection by Inhibiting NF-κB and JAK/STAT Signaling Pathway in IPEC-J2 Porcine Epithelial Cells

Porcine epidemic diarrhea virus (PEDV) infection causes watery diarrhea and vomiting in piglets. The pathogenesis of PEDV infection is related to intestinal inflammation. It is known that 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) has potent anti-inflammatory activity, but it is unknown whether 1,25(OH)₂D₃ can inhibit the PEDV-induced inflammatory response and the underlying mechanism. We used transcriptome analysis, gene and protein expression, RNA interference and overexpression, and other techniques to study the anti-inflammatory effects of 1,25(OH)₂D₃ on PEDV infection in IPEC-J2 cells. The results showed that interleukin 19 (IL-19) and C-C motif chemokine ligand 20 (CCL20) gene expression were enhanced with the increase in PEDV infection time in IPEC-J2 cells. Interestingly, 1,25(OH)₂D₃ supplementation obviously inhibited IL-19 and CCL20 expression induced by PEDV. Meanwhile, we also found that 1,25(OH)₂D₃ reduced p-NF-κB, p-STAT1, and p-STAT3 protein levels induced by PEDV at 24 h post-infection. IκBα and SOCS3, NF-κB, and STAT inhibitor respectively, were increased by 1,25(OH)₂D₃ supplementation upon PEDV infection. In addition, 1,25(OH)₂D₃ supplementation inhibited ISG15 and MxA expression induced by PEDV. Although 1,25(OH)₂D₃ suppressed the JAK/STAT signal pathway and antiviral gene expression, it had no significant effects on PEDV replication and IFN-α-induced antiviral effects. In addition, when the vitamin D receptor (VDR) was silenced by siRNA, the anti-inflammatory effect of 1,25(OH)₂D₃ was inhibited. Meanwhile, the overexpression of VDR significantly downregulated IL-19 and CCL20 expression induced by PEDV infection. Together, our results provide powerful evidence that 1,25(OH)₂D₃ could alleviate PEDV-induced inflammation by regulating the NF-κB and JAK/STAT signaling pathways through VDR. These results suggest that vitamin D could contribute to inhibiting intestinal inflammation and alleviating intestinal damage in PEDV-infected piglets, which offers new approaches for the development of nutritional strategies to prevent PEDV infection in piglets.

Cytochrome P450 enzymes mediated by DNA methylation is involved in deoxynivalenol-induced hepatoxicity in piglets

Deoxynivalenol (DON) is an inevitable contaminant in animal feed and can lead to liver damage, then decreasing appetite and causing growth retardation in piglets. Although many molecular mechanisms are related to hepatoxicity caused by DON, few studies have been done on cytochrome P450 (CYP450) enzymes and DNA methylation. To explore the role of CYP450 enzymes and DNA methylation in DON-induced liver injury, male piglets were fed a control diet, or diet containing 1.0 or 3.0 mg/kg DON for 4 weeks. DON significantly raised the activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutamyl transpeptidase (GGT) (P < 0.01), leading to liver injury. In vivo study found that DON exposure increased the expression of CYP450 enzymes (such as CYP1A1, CYP2E1, CYP3A29) (P < 0.05), and disturbed the expression of nicotinamide N-methyltransferase (NNMT), galanin-like peptide (GALP) and insulin-like growth factor 1 (IGF-1) (P < 0.05), in which DNA methylation affected the expression of these genes. In vitro study (human normal hepatocytes L02) further proved that DON elevated the expression of CYP1A1, CYP2E1 and CYP3A4 (P < 0.05), and inhibited cell growth in a dose-dependent manner, resulting in cell necrosis. More importantly, knockdown of CYP1A1 or CYP2E1 could alleviate DON-induced growth inhibition by promoting IGF-1 expression. Taken together, increased CYP450 enzymes expression was one of the mechanisms of hepatoxicity and growth inhibition induced by DON, suggesting that the decrease of CYP450 enzymes can antagonize the hepatoxicity in animals, which provides some value for animal feed safety.

Intervertebral Disc Degeneration: Functional Analysis of Bite Force and Masseter and Temporal Muscles Thickness

Intervertebral disc degeneration is a pathological condition associated with the intervertebral disc and is related to functional alterations in the human body. This study aimed to evaluate the maximum molar bite force and masseter and temporal muscles thickness in individuals with intervertebral disc degeneration. Thirty-two individuals were divided into two groups: those with degeneration of intervertebral discs (n=16) and those without degeneration (n=16). The maximum molar bite force (on the right and left sides) was measured using a dynamometer. Masseter and temporal muscle thickness during mandibular task rest and dental clenching in maximum voluntary contraction were analysed using ultrasound. Significant differences in the left molar bite force (p=0.04) were observed between the groups (Student's t-test, p&lt;0.05). The intervertebral disc degeneration group had a lower maximum molar bite force. No significant differences in muscle thickness were observed between the masseter and temporal muscles in either group. However, based on clinical observations, the group with intervertebral disc degeneration presented less masseter muscle thickness and greater temporal muscle thickness in both mandibular tasks. Degenerative disease of the intervertebral discs promoted morphofunctional changes in the stomatognathic system, especially in maximum molar bite force and masticatory muscle thickness. This study provides insight into the interaction between spinal pathology and the stomatognathic system, which is important for healthcare professionals who treat patients with functional degeneration.

Toxic mechanisms of the trichothecenes T-2 toxin and deoxynivalenol on protein synthesis

The toxic mechanisms of trichothecenes, including T-2 toxin and deoxynivalenol (DON), are closely related with their effects on protein synthesis. Increasing lines of evidence show that T-2 toxin can reduce the levels of tight junction proteins, and nuclear factor erythroid 2-related factor 2 (Nrf2) by disrupting cellular barriers and the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) and Nrf2/heme oxygenase (HO)-1 pathways. Moreover, it can inhibit aggrecan synthesis, thus causing Kashin-Beck disease. Regarding type B trichothecene, DON inhibits activation marker and β-catenin synthesis by acting on immune cells and the wingless/integrated (Wnt) pathway; it also inhibits cell proliferation and immune surveillance. In addition, DON has been shown to destroy tight junctions, glucose transport, and tumor endothelial marker 8, thus disturbing intestinal function and changing cell migration. This review summarizes the inhibitory effects of the trichothecenes T-2 toxin and DON on different protein synthesis, while discussing their underlying mechanisms. Focus is given to the effects of these toxins on tight junctions, aggrecan, activation markers, and hormones including testosterone under the influence of steroidogenic enzymes. This review can extend the current understanding of the effects of trichothecenes on protein synthesis and help to further understand their toxic mechanisms.

Role of JAK-STAT and PPAR-Gamma Signalling Modulators in the Prevention of Autism and Neurological Dysfunctions

The Janus-kinase (JAK) and signal transducer activator of transcription (STAT) signalling pathways regulate gene expression and control various factors involved in normal physiological functions such as cell proliferation, neuronal development, and cell survival. JAK activation phosphorylates STAT3 in astrocytes and microglia, and this phosphorylation has been linked to mitochondrial damage, apoptosis, neuroinflammation, reactive astrogliosis, and genetic mutations. As a regulator, peroxisome proliferator-activated receptor gamma (PPAR-gamma), in relation to JAK-STAT signalling, prevents this phosphorylation and aids in the treatment of the above-mentioned neurocomplications. Changes in cellular signalling may also contribute to the onset and progression of autism. Thus, PPAR-gamma agonist upregulation may be associated with JAK-STAT signal transduction downregulation. It may also be responsible for attenuating neuropathological changes by stimulating SOCS3 or involving RXR or SMRT, thereby reducing transcription of the various cytokine proteins and genes involved in neuronal damage. Along with JAK-STAT inhibitors, PPAR-gamma agonists could be used as target therapeutic interventions for autism. This research-based review explores the potential involvement and mutual regulation of JAK-STAT and PPAR-gamma signalling in controlling multiple pathological factors associated with autism.

An update on immunotoxicity and mechanisms of action of six environmental mycotoxins

Paradoxically, aflatoxin B1 (AFB1), ochratoxin A (OTA), deoxynivalenol (DON), T-2 toxin (T-2), fumonisin B1 (FB1), and zearalenone (ZEA) have both immunosuppressive and immunostimulatory effects. The immunotoxicity of six mycotoxins exhibits immune suppression or stimulation, which depends on multiple factors. Low doses of mycotoxins can induce an inflammatory response, but elevated levels of ones can induce immunosuppression; long-term instead of short-term mycotoxin exposure is immunosuppressive. These six mycotoxins play anti-inflammatory roles when the immunologic stimulants are present but pro-inflammatory roles when the immunologic stimulants are absent. Pigs are most sensitive animals to mycotoxins, followed by humans and poultry, rodent, and marine organism, and ruminants are the least susceptible. Female animals are more susceptible to mycotoxins than male ones. The immunosuppresion mechanism of mycotoxins are mainly in, oxidative stress, apoptosis and autophagy of immune cells, as well as inhibits the immunity-related signal pathways; and AFB1, OTA, DON, and T-2 induce immunostimulation via directly activating the TLRs/NF-κB pathway and other crossing pathways including cyclooxygenase-2 (COX-2) and mitogen-activated protein kinase (MAPK). This review strongly dispels the viewpoint that "immunotoxicity is equivalent to immunosuppression", clearly demonstrates the mechanistic pathway and how it contributes to immunosuppression or immunostimulation, thereby providing reliable references for future studies.

Cardiomyocyte IL-1R2 protects heart from ischemia/reperfusion injury by attenuating IL-17RA-mediated cardiomyocyte apoptosis

Myocardial ischemia reperfusion (I/R) injury is a complex process with intense inflammatory response and cardiomyocyte apoptosis. As a decoy receptor of IL-1β, Interleukin-1 receptor type 2 (IL-1R2) inhibits IL-1β signaling. However, its role in I/R injury remains unknown. Here we found that the serum levels of IL-1R2 were significantly increased in patients with acute myocardial infarction (AMI) following interventional therapy. Similarly, after myocardial I/R surgery, IL-1R2 expression was significantly increased in heart of wild-type mice. In addition, IL-1R2-deficient mice heart showed enlarged infarct size, increased cardiomyocyte apoptosis together with reduced cardiac systolic function. Following exposure to hypoxia and reoxygenation (H/R), neonatal rat ventricular myocytes (NRVM) significantly increased IL-1R2 expression relying on NF-κB activation. Consistently, IL-1R2-deficient mice increased immune cells infiltrating into heart after surgery, which was relevant with cardiac damage. Additionally, IL-1R2 overexpression in cardiomyocyte protected cardiomyocyte against apoptosis through reducing the IL-17RA expression both in vivo and in vitro. Our results indicate that IL-1R2 protects cardiomyocytes from apoptosis, which provides a therapeutic approach to turn down myocardial I/R injury.

Neurotoxic Potential of Deoxynivalenol in Murine Brain Cell Lines and Primary Hippocampal Cultures

Chronic exposure to the mycotoxin deoxynivalenol (DON) from grain-based food and feed affects human and animal health. Known consequences include entereopathogenic and immunotoxic defects; however, the neurotoxic potential of DON has only come into focus more recently due to the observation of behavioural disorders in exposed farm animals. DON can cross the blood-brain barrier and interfere with the homeostasis/functioning of the nervous system, but the underlying mechanisms of action remain elusive. Here, we have investigated the impact of DON on mouse astrocyte and microglia cell lines, as well as on primary hippocampal cultures by analysing different toxicological endpoints. We found that DON has an impact on the viability of both glial cell types, as shown by a significant decrease of metabolic activity, and a notable cytotoxic effect, which was stronger in the microglia. In astrocytes, DON caused a G1 phase arrest in the cell cycle and a decrease of cyclic-adenosine monophosphate (cAMP) levels. The pro-inflammatory cytokine tumour necrosis factor (TNF)-α was secreted in the microglia in response to DON exposure. Furthermore, the intermediate filaments of the astrocytic cytoskeleton were disturbed in primary hippocampal cultures, and the dendrite lengths of neurons were shortened. The combined results indicated DON's considerable potential to interfere with the brain cell physiology, which helps explain the observed in vivo neurotoxicological effects.

High resistance to Toxoplasma gondii infection in inducible nitric oxide synthase knockout rats

Nitric oxide (NO) is an important immune molecule that acts against extracellular and intracellular pathogens in most hosts. However, after the knockout of inducible nitric oxide synthase (iNOS^−/−) in Sprague Dawley (SD) rats, these iNOS^−/− rats were found to be completely resistant to Toxoplasma gondii infection. Once the iNOS^−/− rat peritoneal macrophages (PMs) were infected with T. gondii, they produced high levels of reactive oxygen species (ROS) triggered by GRA43 secreted by T. gondii, which damaged the parasitophorous vacuole membrane and PM mitochondrial membranes within a few hours post-infection. Further evidence indicated that the high levels of ROS caused mitochondrial superoxide dismutase 2 depletion and induced PM pyroptosis and cell death. This discovery of complete resistance to T. gondii infection, in the iNOS^−/−-SD rat, demonstrates a strong link between NO and ROS in immunity to T. gondii infection and showcases a potentially novel and effective backup innate immunity system.

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iNOS^−/−-SD rats show strong resistance to Toxoplasma gondii infection

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iNOS^−/−-SD rat PMs resist T. gondii infection through ROS upregulation

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The T. gondii infection results in PM pyroptosis in iNOS^−/−-SD rats

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GRAs play a key role in the activation of resistance in iNOS^−/−-SD rat PMs

Chromatin Accessibility and Transcriptomic Alterations in Murine Ovarian Granulosa Cells upon Deoxynivalenol Exposure

Deoxynivalenol (DON) is a common environmental toxin that is secreted by fusarium fungi that frequently contaminates feedstuff and food. While the detrimental effects of DON on human and animal reproductive systems have been well recognized, the underlying mechanism remains poorly understood. Ovarian granulosa cells (GCs), which surround oocytes, are crucial for regulating oocyte development, mainly through the secretion of hormones such as estrogen and progesterone. Using an in vitro model of murine GCs, we characterized the cytotoxic effects of DON and profiled genome-wide chromatin accessibility and transcriptomic alterations after DON exposure. Our results suggest that DON can induce decreased viability and growth, increased apoptosis rate, and disrupted hormone secretion. In total, 2533 differentially accessible loci and 2675 differentially expressed genes were identified that were associated with Hippo, Wnt, steroid biosynthesis, sulfur metabolism, and inflammation-related pathways. DON-induced genes usually have a concurrently increased occupancy of active histone modifications H3K4me3 and H3K27ac in their promoters. Integrative analyses identified 35 putative directly affected genes including Adrb2 and Fshr, which are key regulators of follicular growth, and revealed that regions with increased chromatin accessibility are enriched with the binding motifs for NR5A1 and NR5A2, which are important for GCs. Moreover, DON-induced inflammatory response is due to the activation of the NF-κB and MAPK signaling pathways. Overall, our results provide novel insights into the regulatory elements, genes, and key pathways underlying the response of ovarian GCs to DON cytotoxicity.

The NO-dependent caspase signaling pathway is a target of deoxynivalenol in growth inhibition in vitro

DON is commonly found in foods and feeds; it presents health risks, especially an increase of growth inhibition in humans, particularly infants and young children. However, there are relatively few research studies devoted to the mechanism of DON-mediated growth retardation. Interestingly, our results showed that DON does not cause any significant production of ROS but results in a persistent and significant release of NO with iNOS increasing activity, mitochondrial ultrastructural changes and decreasing ΔΨm. Moreover, the significant decreases in GH production and secretion induced by DON were dose-dependent, accompanied by an increase of caspase 3, 8 and 9, IL-11, IL-lβ and GHRH. NO scavenging agent (haemoglobin) and free radical scavenging agent (N-acetylcysteine) partially reversed mitochondrial damage, and Z-VAD-FMK increased the levels of GH and decreased the levels of caspase 3, 8 and 9, while haemoglobin decreased the levels of caspase 3, 8 and 9, indicating that NO is the primary target of DON-mediated inhibition. Present research study firstly demonstrated that NO is a key mediator of DON-induced growth inhibition and plays critical roles in the interference of GH transcription and synthesis. The current research is conducive to future research on the molecular mechanisms of DON-induced growth inhibition in humans, especially children.

Long non-coding RNAs in metabolic disorders: pathogenetic relevance and potential biomarkers and therapeutic targets

BACKGROUND

It has been suggested that dysregulation of long non-coding RNAs (lncRNAs) could be associated with the incidence and development of metabolic disorders.

AIM

Accordingly, this narrative review described the molecular mechanisms of lncRNAs in the development of metabolic diseases including insulin resistance, diabetes, obesity, non-alcoholic fatty liver disease (NAFLD), cirrhosis, and coronary artery diseases (CAD). Furthermore, we investigated the up-to-date findings on the association of deregulated lncRNAs in the metabolic disorders, and potential use of lncRNAs as biomarkers and therapeutic targets.

CONCLUSION

LncRNAs/miRNA/regulatory proteins axis plays a crucial role in progression of metabolic disorders and may be used in development of therapeutic and diagnostic approaches.

Role of DNA methylation-related chromatin remodeling in aryl hydrocarbon receptor-dependent regulation of T-2 toxin highly inducible Cytochrome P450 1A4 gene

Mycotoxins are toxic secondary metabolites produced by food-contaminating fungi, which lead to global epigenetic changes and cause toxicity to both farm animals and humans. However, whether mycotoxins induce gene-specific epigenetic alterations associated with inducible downstream gene expression is unclear as are the underlying regulatory mechanisms. Here, we found that T-2 toxin and its deacetylated metabolites but not deoxynivalenol (DON) or other representative mycotoxins highly induced the expression of cytochrome P450 1A4 (CYP1A4) in both Leghorn male hepatoma (LMH) cells and chicken primary hepatocytes, and this effect was related to the regulation of both aryl hydrocarbon receptor (AhR) and DNA methylation. We used methylation-sensitive restriction enzyme digestion-qPCR (MSRE-qPCR) and chromatin immunoprecipitation (ChIP) assays and found that the binding of DNA methyltransferase 1 (DNMT1) and histone deacetylase 2 (HDAC2) to highly methylated CpG island 3-2 at the enhancer of CYP1A4 was accompanied by the recruitment of the repressive histone modification marker H3K27me3, inducing a silent state. In turn, T-2 toxin stimulation enriched the binding of AhR to demethylated CpG island 3-2, which facilitated p300 and H3K9ac recruitment and ultimately generated an activated chromatin structure at the enhancer by increasing the active histone modification markers, including H3K4me3, H3K27ac, and H3K14ac. Interestingly, T-2 toxin-induced AhR activation also facilitated RNA polymerase II binding to CpG island 2, which may form a transcriptionally active chromatin structure at the promoter and ultimately transactivate CYP1A4. Our findings provide novel insights into the epigenetic regulation of T-2 toxin-induced gene expression.

Reduced apoptosis of monocytes and macrophages is associated with their persistence in wounds of diabetic mice

Monocytes and macrophages (Mo/MΦ) rapidly accumulate in skin wounds after injury, then disappear as healing progresses. However, the mechanisms underlying their ultimate fate in wounds remain to be elucidated. Here, we show that apoptosis of Mo/MΦ parallels their reduction as wound healing progresses in non-diabetic mice. scRNAseq analysis confirmed enriched apoptosis GO pathways on day 6 post-injury in wound Mo/MΦ from non-diabetic mice. In contrast, there was significantly less Mo/MΦ apoptosis in wounds from diabetic mice, particularly in the pro-inflammatory Ly6C+ population, which may contribute to persistent Mo/MΦ accumulation and chronic inflammation. scRNAseq analysis implicated TNF, MAPK, Jak-STAT, and FoxO signaling pathways in promoting wound Mo/MΦ apoptosis in non-diabetic mice while cell proliferation related pathways appeared to be activated in diabetic mice. These novel findings indicate that reduced apoptosis is a contributor to persistent Mo/MΦ accumulation in diabetic wounds. These findings also highlight pathways that may regulate Mo/MΦ apoptosis during wound healing, which could be targeted to help resolve inflammation and improve healing.

Protective Effect of Organic Selenium on Oxidative Damage and Inflammatory Reaction of Rabbit Kidney Induced by T-2 Toxin

T-2 toxin is a member of a class of mycotoxins produced by a variety of Fusarium species under appropriate temperature and humidity conditions and is a common contaminant in food and feedstuffs of cereal origin. Selenium is an indispensable element in animals, regulates a variety of biological functions of the body, and can antagonize metal and mycotoxin poisoning to a certain extent. However, the effect of selenium on kidney injury induced by T-2 toxin has not been reported. In this study, 50 New Zealand rabbits were divided into 5 groups (the control group, T-2 toxin group, low-dose Se + T-2 toxin group, medium-dose Se + T-2 toxin group, and high-dose Se + T-2 toxin group). Rabbits were examined after oral administration of different doses of selenomethionine (SeMet) for 21 days and after perfusion with 0.4 mg/kg T-2 toxin (or the same dose of olive oil in the control group) for 5 days. We found that T-2 toxin induced kidney function damage and increased the levels of ROS and the contents of inflammatory factors. Renal structure was pathologically damaged. However, we found that after pretreatment with 0.2 mg/kg SeMet, oxidative stress, the inflammatory response, and pathological damage induced by T-2 toxin were attenuated. The results indicate that a low dose (0.2 mg/kg) of SeMet effectively reversed T-2 toxin-induced kidney injury in rabbits.

Neuroimmune disruptions from naturally occurring levels of mycotoxins

Substantial pieces of evidence support the potential of exogenous toxins in disrupting neuroimmune homeostasis. It appears that mycotoxins are one of the noticeable sources of naturally occurring substances dysregulating the immune system, which involves the physiology of many organs, such as the central nervous system (CNS). The induction of inflammatory responses in microglial cells and astrocytes, the CNS resident cells with immunological characteristics, could interrupt the hemostasis upon even with low-level exposure to mycotoxins. The inevitable widespread occurrence of a low level of mycotoxins in foods and feed is likely increasing worldwide, predisposing individuals to potential neuroimmunological dysregulations. This paper reviews the current understanding of mycotoxins' neuro-immunotoxic features under low-dose exposure and the possible ways for detoxification and clearance as a perspective.

Stattic alleviates acute hepatic damage induced by LPS/d-galactosamine in mice

Increasing evidence indicates that signal transducer and activator of transcription 3 (STAT3), a vital transcription factor, plays crucial roles in the regulation of inflammation. STAT3 has become a novel therapeutic target for intervention in inflammation-related disorders. However, it remains unclear whether STAT3 plays a part in acute hepatic damage. To investigate the effects of STAT3 here, LPS/d-GalN-induced hepatic damage was induced in mice, the STAT3 inhibitor Stattic was administered, and the degree of liver injury, inflammation, and hepatocyte apoptosis were investigated. The results showed that Stattic mitigated the hepatic morphologic abnormalities and decreased the level of aminotransferase in LPS/D-GalN-insulted mice. The results also indicated that Stattic decreased the levels of TNF-α and IL-6, prevented the activation of the caspase cascade, suppressed cleavage of PARP, and decreased the quantity of TUNEL-positive cells. These results suggest that Stattic provided protective benefits in LPS/d-GalN-induced hepatic damage, and the protective effects might be associated with its anti-inflammatory and anti-apoptotic effects. Therefore, STAT3 might become a novel target for intervening in inflammation-based and apoptosis-based hepatic disorders.

Beneficial Effects of Rosmarinic Acid on IPEC-J2 Cells Exposed to the Combination of Deoxynivalenol and T-2 Toxin

Mycotoxin contamination in feedstuffs is a worldwide problem that causes serious health issues both in humans and animals, and it contributes to serious economic losses. Deoxynivalenol (DON) and T-2 toxin (T-2) are major trichothecene mycotoxins and are known to challenge mainly intestinal barrier functions. Polyphenolic rosmarinic acid (RA) appeared to have antioxidant and anti-inflammatory properties in vitro. The aim of this study was to investigate protective effects of RA against DON and T-2 or combined mycotoxin-induced intestinal damage in nontumorigenic porcine cell line, IPEC-J2. It was ascertained that simultaneous treatment of DON and T-2 (DT2: 1 μmol/L DON + 5 nmol/L T - 2) for 48 h and 72 h reduced transepithelial electrical resistance of cell monolayer, which was restored by 50 μmol/L RA application. It was also found that DT2 for 48 h and 72 h could induce oxidative stress and elevate interleukin-6 (IL-6) and interleukin-8 (IL-8) levels significantly, which were alleviated by the administration of RA. DT2 administration contributed to the redistribution of claudin-1; however, occludin membranous localization was not altered by combined mycotoxin treatment. In conclusion, beneficial effect of RA was exerted on DT2-deteriorated cell monolayer integrity and on the perturbated redox status of IPEC-J2 cells.

3-Acetyldeoxynivalenol induces lysosomal membrane permeabilization-mediated apoptosis and inhibits autophagic flux in macrophages

3-Acetyldeoxynivalenol (3-Ac-DON), the acetylated derivative of deoxynivalenol (DON), has been reported to be coexisted with DON in various cereal grains. Ingestion of grain-based food products contaminated by 3-Ac-DON might exert deleterious effects on the health of both humans and animals. However, the biological toxicity of 3-Ac-DON on macrophages and the underlying mechanisms remain largely unknown. In the present study, we showed that RAW 264.7 macrophages treated with 0.75 or 1.50 μg/mL of 3-Ac-DON resulted in DNA damage and the related cell cycle arrest at G1 phase and cell death, activation of the ribotoxic stress and the endoplasmic reticulum (ER) stress responses. The 3-Ac-DON-induced cell death was accompanied by a protective autophagy, because gene silencing of Atg5 using the small interfering RNA enhanced cell death. Results of further experiments revealed a role for lysosomal membrane permeabilization in the 3-Ac-DON triggered inhibition of autophagic flux. Additional work also showed that increased lysosomal biogenesis and leakage of cathepsin B (CTSB) from lysosomes to cytosol was critical for the 3-Ac-DON-induced cell death. Importantly, 3-Ac-DON-induced DNA damage and cell death were rescued by CA-074-me, a CTSB inhibitor. Collectively, these results indicated a critical role of lysosomal membrane permeabilization in the 3-Ac-DON-induced apoptosis of RAW 264.7 macrophages.

An update on T-2 toxin and its modified forms: metabolism, immunotoxicity mechanism, and human exposure assessment

T-2 toxin is the most toxic trichothecene mycotoxin, and it exerts potent toxic effects, including immunotoxicity, neurotoxicity, and reproductive toxicity. Recently, several novel metabolites, including 3',4'-dihydroxy-T-2 toxin and 4',4'-dihydroxy-T-2 toxin, have been uncovered. The enzymes CYP3A4 and carboxylesterase contribute to T-2 toxin metabolism, with 3'-hydroxy-T-2 toxin and HT-2 toxin as the corresponding primary products. Modified forms of T-2 toxin, including T-2-3-glucoside, exert their immunotoxic effects by signaling through JAK/STAT but not MAPK. T-2-3-glucoside results from hydrolyzation of the corresponding parent mycotoxin and other metabolites by the intestinal microbiota, which leads to enhanced toxicity. Increasing evidence has shown that autophagy, hypoxia-inducible factors, and exosomes are involved in T-2 toxin-induced immunotoxicity. Autophagy promotes the immunosuppression induced by T-2 toxin, and a complex crosstalk between apoptosis and autophagy exists. Very recently, "immune evasion" activity was reported to be associated with this toxin; this activity is initiated inside cells and allows pathogens to escape the host immune response. Moreover, T-2 toxin has the potential to trigger hypoxia in cells, which is related to activation of hypoxia-inducible factor and the release of exosomes, leading to immunotoxicity. Based on the data from a series of human exposure studies, free T-2 toxin, HT-2 toxin, and HT-2-4-glucuronide should be considered human T-2 toxin biomarkers in the urine. The present review focuses on novel findings related to the metabolism, immunotoxicity, and human exposure assessment of T-2 toxin and its modified forms. In particular, the immunotoxicity mechanisms of T-2 toxin and the toxicity mechanism of its modified form, as well as human T-2 toxin biomarkers, are discussed. This work will contribute to an improved understanding of the immunotoxicity mechanism of T-2 toxin and its modified forms.

Epigenetic upregulation of galanin-like peptide mediates deoxynivalenol induced-growth inhibition in pituitary cells

Deoxynivalenol (DON) is an unavoidable contaminant in human food, animal feeds, and agricultural products. Growth retardation in children caused by extensive DON pollution has become a global problem that cannot be ignored. Previous studies have shown that DON causes stunting in children through intestinal dysfunction, insulin-like growth factor-1 (IGF-1) axis disorder and peptide YY (PYY). Galanin-like peptide (GALP) is an important growth regulator, but its role in DON-induced growth retardation is unclear. In this study, we report the important role of GALP during DON-induced growth inhibition in the rat pituitary tumour cell line GH3. DON was found to increase the expression of GALP through hypomethylationin the promoter region of the GALP gene and upregulate the expression of proinflammatory factors, while downregulate the expression of growth hormone (GH). Furthermore, GALP overexpression promoted proinflammatory cytokines, including TNF-α, IL-1β, IL-11 and IL-6, and further reduced cell viability and cell proliferation, while the inhibitory effect of GALP was the opposite. The expression of GALP and insulin like growth factor binding protein acid labile subunit (IGFALS) showed the opposite trend, which was the potential reason for the regulation of cell proliferation by GALP. In addition, GALP has anti-apoptotic effects, which could not eliminate the inflammatory damage of cells, thus aggravating cell growth inhibition. The present findings provide new mechanistic insights into the toxicity of DON-induced growth retardation and suggest a therapeutic potential of GALP in DON-related diseases.

Anorexic responses to trichothecene deoxynivalenol and its congeners correspond to secretion of tumor necrosis factor-α and interleukin-1β

Type B trichothecene mycotoxins comprise deoxynivalenol ("Vomitoxin", DON) and four structually related congeners: 15-acetyl- and 3-acetyl-deoxynivalenol (15-ADON and 3-ADON), nivalenol (NIV), 4-acetyl-nivalenol (fusarenon X, FX). These foodborne mycotoxins has been linked to food poisoning leading to anorexic response in human and several animal species. However, the pathophysiological basis for anorexic effect is relatively unclear. The goal of this research was to compare anorexic effect to type B trichothecenes and relate these effects to two common cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) following oral and IP exposure. Both cytokines were increased within 1-2 h in plasma and returned to basal concentrations at 6 h following exposure to DON and ADONs. FX evoked both cytokines with initial time and duration at 1-2 h and > 6 h, respectively. Elevation of TNF-α and IL-1β induced by orally exposure to NIV did not occur until 2 h and recovered to basal concentrations at 6 h. Both cytokines were elevated at 1 h and lasted more than 6 h following IP exposure to NIV. Type B trichothecenes stimulated plasma secretion of both cytokines that were consistent with reduction of food intake. In conclusion, our findings demonstrate that TNF-α and IL-1β act critical roles in type B trichothecenes-induced anorexic response.

Transcriptional regulation of seven cyadox-related genes mainly activated by PI3K and NF-кB signaling pathways in PK-15 cells

Cyadox, a new antibacterial agent as the quinoxaline-1, 4-dioxides, has a good antibacterial and growth-promoting effect, and has the advantages of lower toxicity, adequate safety and faster absorption. Seven differential expressed genes (DEGs) induced by cyadox were screened in swine liver tissues, including Insulin-like Growth Factor-1 (IGF-1), Epidermal Growth Factor (EGF), Poly ADP-ribose polymerase (PARP), the Defender Against Apoptotic Death 1 (DAD1), Complement Component 3 (C3), Transketolase (TK) and cyadox-related novel gene (CRNG). To elucidate the signal mechanism that cyadox altered these genes expression, the time-effect relationship and signaling pathways related to 7 DEGs induced by cyadox were determined in Porcine Kidney-15 (PK-15) cells by RT-qPCR and the application of various signal pathway inhibitors. The phosphorylation levels of signal factors in PK-15 cells were detected by Western blot. The analyses demonstrated that, the mRNA expressions of 7 DEGs were significantly enhanced by cyadox mainly through the phosphoinositide 3-kinase (PI3K) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-кB) signaling pathways in PK-15 cells. Furthermore, EGF might be the early response gene of cyadox to activate downstream signaling pathways and regulates the expression of other related genes or directly exerting biological effects. In brief, cyadox mainly regulates the expression of these 7 genes by PI3K and NF-кB signaling pathways to exert it's antibacterial and growth-promoting activity in PK-15 cells.

MiR-155-5p plays as a "janus" in the expression of inflammatory cytokines induced by T-2 toxin

Although many studies have shown that inflammatory response plays a crucial role in the various toxic effects of T-2 toxin, there are relatively few reports on the mechanism of this phenomenon. Meanwhile, accumulating evidence has shown that miR-155-5p is activated in the inflammatory response. As molecular pathways and mechanisms involved in T-2 toxin-induced inflammatory response are poorly elucidated, we assessed whether miR-155-5p is involved in the inflammation effects mediated by T-2 toxin. Treatment of RAW264.7 cells with T-2 toxin (14 nM and 12 h) resulted in inflammatory response and associated with alteration of the gene expression signature of miR-155-5p. Knockdown or overexpression of miR-155-5p both indicated that miR-155-5p positively regulated the expression of the inflammation factors. Moreover, bioinformatics prediction and luciferase assay indicated that atg3 and rheb are targets of miR-155-5p. However, atg3 and SOCS1 play positive roles in the inflammatory response regulated by miR-155-5p, while rheb plays a negative role. In addition, the in vivo study showed that single administration of T-2 toxin in mice enhances spleen immune response, which was accompanied by an overexpression of miR-155-5p. These findings indicate that miR-155-5p might have an important role associated with the inflammatory response induced by T-2 toxin. In conclusion, a dual character of miR-155-5p in inflammation response was revealed, which might exist in other reactions in which miR-155-5p is involved.

Cellular Effects of T-2 Toxin on Primary Hepatic Cell Culture Models of Chickens

Trichothecene mycotoxins such as T-2 toxin cause severe problems for agriculture, as well as for veterinary medicine. As liver is one of the key organs in metabolism, the main aim of our study was to investigate the immunomodulatory and cytotoxic effects of T-2 toxin, using primary hepatocyte mono-culture and hepatocyte-nonparenchymal cell (predominantly Kupffer cell) co-culture models of chicken. Cultures were exposed to 10 (T10 group), 100 (T100 group) and 1000 (T1000 group) nmol/L T-2 toxin treatment for 8 or 24 h. Alterations of cellular metabolic activity, the production of reactive oxygen species (extracellular H2O2), heat shock protein 70 (HSP70), and the concentration of different inflammatory cytokines such as interleukin (IL-)6 and IL-8 were investigated. Metabolic activity was intensely decreased by T-2 toxin administration in all of the cell culture models, in every applied concentration and incubation time. Concentrations of HSP70 and IL-8 were significantly increased in hepatocyte mono-cultures exposed to higher T-2 toxin levels (both in T100 and T1000 groups for HSP70 and in T1000 group for IL-8, respectively) compared to controls after 24 h incubation. Similarly, IL-6 levels were also significantly elevated in the T100 and T1000 groups in both of mono- and co-cultures, but only after 8 h of incubation time. In spite of the general harmful effects of T-2 toxin treatment, no significant differences were observed on reactive oxygen species production. Furthermore, the two cell culture models showed different levels of H2O2, HSP70, and IL-8 concentrations independently of T-2 toxin supplementation. In conclusion, the established primary cell cultures derived from chicken proved to be proper models to study the specific molecular effects caused by T-2 toxin. Metabolic activity and immune status of the different examined cell cultures were intensively affected; however, no changes were found in H2O2 levels.

T-2 Toxin-Induced Oxidative Stress Leads to Imbalance of Mitochondrial Fission and Fusion to Activate Cellular Apoptosis in the Human Liver 7702 Cell Line

T-2 toxin, as a highly toxic mycotoxin to humans and animals, induces oxidative stress and apoptosis in various cells and tissues. Apoptosis and mitochondrial fusion/fission are two tightly interconnected processes that are crucial for maintaining physiological homeostasis. However, the role of mitochondrial fusion/fission in apoptosis of T-2 toxin remains unknown. Hence, we aimed to explore the putative role of mitochondrial fusion/fission on T-2 toxin induced apoptosis in normal human liver (HL-7702) cells. T-2 toxin treatment (0, 0.1, 1.0, or 10 μg/L) for 24 h caused decreased cell viability and ATP concentration and increased production of (ROS), as seen by a loss of mitochondrial membrane potential (∆Ψm) and increase in mitochondrial fragmentation. Subsequently, the mitochondrial dynamic imbalance was activated, evidenced by a dose-dependent decrease and increase in the protein expression of mitochondrial fusion (OPA1, Mfn1, and Mfn2) and fission (Drp1 and Fis1), respectively. Furthermore, the T-2 toxin promoted the release of cytochrome c from mitochondria to cytoplasm and induced cell apoptosis triggered by upregulation of Bax and Bax/Bcl-2 ratios, and further activated the caspase pathways. Taken together, these results indicate that altered mitochondrial dynamics induced by oxidative stress with T-2 toxin exposure likely contribute to mitochondrial injury and HL-7702 cell apoptosis.

T-2 toxin-induced DRP-1-dependent mitophagy leads to the apoptosis of mice Leydig cells (TM3)

T-2 toxin, one member of the type A trichothecene family, induces the apoptosis of human hepatocytes (L02) and murine Leydig cells (TM3), as well as mitochondrial dysfunctions. In the present study, we attempted to investigate whether T-2 toxin toxicity is related to mitochondrial dysfunction and mitophagy. We found that T-2 toxin might induce autophagy and mitophagy in TM3 cells (TM3) in a concentration-dependent manner. In addition, T-2 toxin could induce mitochondrial dysfunction, depolarization, and fission concentration-dependently. The inducible effects of T-2 toxin on mitophagy, mitochondrial dysfunction, and cell apoptosis could all be significantly reversed by autophagy inhibitor, 3 MA. Finally, DRP-1 participated in the inducible effects of T-2 toxin on TM3 cell mitophagy, mitochondrial dysfunction, and cell apoptosis. In summary, mitophagy and mitochondrial dysfunction are essential mechanisms of the toxicity induced by T-2 toxin. Thus, our findings provide a rationale for further studies on selectively targeting mitophagy to improve mitochondrial dysfunction and to protect cells from T-2 toxin-induced toxicity.

Comparison of the toxic mechanism of T-2 toxin and deoxynivalenol on human chondrocytes by microarray and bioinformatics analysis

T-2 toxin and deoxynivalenol (DON) are two representative mycotoxins that are commonly found in cereals and agricultural products. As T-2 toxin and DON are considered the cause of Kashin-Beck disease, a special osteoarticular disease, chondrocytes would be a vital target site for these toxins. To fully understand the toxicity effects of T-2 toxin and DON on chondrocytes, the present study investigated and compared the gene expression profiles and underlying mechanisms of T-2 toxin and DON on cultured human chondrocytes by microarray and bioinformatics analysis. Normal human chondrocytes were treated with T-2 toxin at 0.01 μg/ml and DON at 1.0 μg/ml for 72 h and analyzed by microarray using Affymetrix Human Gene Chip. Comprehensive analysis, including gene ontology, pathways and gene-gene networks was performed to identify the crucial gene functions, related signal pathways and key genes. A total of 175 and 237 differentially expressed genes were identified in human chondrocytes for T-2 toxin and DON treatment, respectively. Of these, 47 had the same expression tendencies in the two groups. The protein-protein interaction network analysis showed that the 10 hub genes were different between the two groups. Our results provide a comprehensive understanding of the toxic mechanism of T-2 toxin and DON on human chondrocytes and suggest that although T-2 toxin and DON showed some similar toxic mechanisms in human chondrocytes, they also had different toxic characteristics.

Evaluation of Collagen and Elastin Content in Skin of Multiparous Minks Receiving Feed Contaminated with Deoxynivalenol (DON, Vomitoxin) with or without Bentonite Supplementation

Simple Summary

The presence of mycotoxins in products intended for consumption is harmful to the health of both people and animals. One of the most abundant mycotoxins in mink’s feed, often contaminating cereal grains, is a mycotoxin produced by the fungi Fusarium spp. deoxynivalenol (DON). The aim of the study was to investigate whether and how the long-term supply of this mycotoxin in feed influences the skin of adult female minks. An additional objective was to assess the effects of the bentonite additive to feed contaminated by DON, which has the ability to reduce the impact of mycotoxins. The scrapes of the skin were collected from animals after euthanasia and before pelting. After preparing histological slides, samples were examined microscopically. The thickness of the epidermis and dermis was investigated and the presence of elastin and collagen. These parameters determine the quality of the fur skins and economic aspect of this animal husbandry. The results showed that DON causes a decrease in the presence of total collagen and absence of immature collagen, thus reducing the elasticity and flexibility of the skin. The addition the bentonite to feed stimulates the production of collagen, restoring the proper relationship between the tested parameters in mink’s skin.

Abstract

Deoxynivalenol (DON, vomitoxin) is considered one of the most dangerous mycotoxins contaminating cereal products for food and feed. One of the protective methods against the adverse effect of DON on mink health is to use a component such as bentonite as a feed supplement to allow toxins absorption. The aim of this study was to determine the effect of DON, administered alone or with bentonite, on the histological structure of the skin and the content of collagen and elastin. A multiparous minks from control group (not exposed to DON) and a study groups receiving fed with DON-containing wheat for seven months: I: at a concentration of 1.1 mg/kg of feed, II: at a concentration of 3.7 mg/kg, III: DON at a concentration of 3.7 mg/kg and bentonite at a concentration of 0.5 kg/1000 kg of feed (0.05%) and IV: DON at a concentration of 3.7 mg/kg and bentonite at a concentration 2 kg/1000 kg (0.2%). After performing euthanasia and before pelting, skin samples of 2 cm in diameter were drawn from the multiparous minks from the lateral surface of the right anterior limb. Our obtained results clearly indicate that DON administered for a period of seven months at a dose of 1.1 mg/kg significantly changes the thickness of skin of a multiparous mink. It causes an increase in the percentage of elastin from 5.9% to 9.4% and a decrease in immature collagen, which results in a change in the collagen/elastin ratio from 10/1 to 5/1. A dose of 3.7 mg/kg DON in feed without or with 0.05% bentonite causes the absence of immature collagen in the dermis, but the addition of 0.2% bentonite in the feed reveals the presence of immature collagen and increase the percentage of the elastin.

JAK2/STAT1-mediated HMGB1 translocation increases inflammation and cell death in a ventilator-induced lung injury model

Janus kinase 2/signal transducer and activators of transcription 1 (JAK2/STAT1) signaling is a common pathway that contributes to numerous inflammatory disorders, including different forms of acute lung injury (ALI). However, the role of JAK2/STAT1 in ventilator-induced lung injury (VILI) and its underlying mechanism remain unclear. In this study, using lipopolysaccharide (LPS) inhalation plus mechanical ventilation as VILI mouse model, we found that the administration of JAK2 inhibitor AZD1480 markedly attenuated lung destruction, diminished protein leakage, and inhibited cytokine release. In addition, when mouse macrophage-like RAW 264.7 cells were exposed to LPS and cyclic stretch (CS), AZD1480 prevented cell autophagy, reduced apoptosis, and suppressed lactate dehydrogenase release by downregulating JAK2/STAT1 phosphorylation levels and inducing HMGB1 translocation from the nucleus to the cytoplasm. Furthermore, HMGB1 and STAT1 knockdown attenuated LPS+CS-induced autophagy and apoptosis in RAW 264.7 cells. In conclusion, these findings reveal the connection between the JAK2/STAT1 pathway and HMGB1 translocation in mediating lung inflammation and cell death in VILI, suggesting that these molecules may serve as novel therapeutic targets for VILI.

Deoxynivalenol induces apoptosis and disrupts cellular homeostasis through MAPK signaling pathways in bovine mammary epithelial cells

Deoxynivalenol (DON), a fungus-derived mycotoxin, also known as vomitoxin, is found in a wide range of cereal grains and grain-based food products. The biological toxicity of DON has been described in various species, but its toxicity and functional effects in mammary epithelial cells are unclear. In this study, we investigated the effect of DON on bovine mammary epithelial (MAC-T) cells using mechanistic approaches. We detected DON-induced cell cycle abrogation and calcium deficiency, leading to apoptotic cell death via MAPK signaling pathways. Moreover, we studied the transcriptional activation of blood and milk junctional regulators as well as inflammatory cytokines in response to DON. The results of this study contribute to a comprehensive understanding of DON-associated toxicity mechanisms in bovine mammary epithelial cells, which may facilitate the enhancement of milk stabilization in parallel with the establishment of safety profiles to protect against DON contamination in livestock farms and in the food industry.

DNA methylation and RASSF4 expression are involved in T-2 toxin-induced hepatotoxicity

T-2 toxin is a secondary metabolite produced by Fusarium species and commonly contaminates food and animal feed. T-2 toxin can induce hepatotoxicity through apoptosis and oxidative stress; however, the underlying mechanism is not clear. Recent studies indicated that RASSF4, a member of the RASSF family, participates in cell apoptosis and some cancers due to its inactivation via DNA hypermethylation. However, its role in T-2 toxin-induced liver toxicity is poorly understood. Therefore, in this study, female Wistar rats were given a single dose of T-2 toxin at 2 mg/kg b.w. and were sacrificed at 1, 3 and 7 days post-exposure. A normal rat liver cell line (BRL) was exposed to different concentrations of T-2 toxin (10, 20, 40 nM) for 4, 8, 12 h, respectively. Histopathological analysis revealed with apoptosis in some liver cells and clear proliferation under T-2 toxin exposure. Expression analysis by immunohistochemical assays, quantitative real-time PCR (qPCR) and western blot demonstrated that T-2 toxin activated PI3K-Akt/Caspase/NF-κB signaling pathways. Additionally, DNA methylation assays revealed that the expression of RASSF4 was silenced by promoter hypermethylation after exposure to T-2 toxin for 1 and 3 days as compared to the control group. Moreover, joint treatment of 5-Aza-2'-deoxycytidine (DAC) (5 μM) and T-2 toxin (40 nM) increased expression of RASSF4 and PI3K-Akt/caspase/NF-κB signaling pathways-related genes, inducing cell apoptosis. These findings for the first time demonstrated that DNA methylation regulated the RASSF4 expression under T-2 toxin, along with the activation of its downstream pathways, resulting in apoptosis.

Molecular Characterization and Biological Function of a Novel LncRNA CRNG in Swine

Our previous study has showed that a novel gene is differentially expressed in the liver of cyadox-fed piglets, but its sequence and function are unknown. Here, rapid amplification of cDNA ends (RACE) and bioinformatics analysis showed that the novel gene is 953 bp without protein-coding ability and locates in chromosome 11. Hence, we identified the novel gene as long non-coding RNA (lncRNA) and named it cyadox-related novel gene (CRNG). Fluorescence in situ hybridization (FISH) showed that CRNG mainly distributes in cytoplasm. Moreover, microarray assay in combination with CRNG interference and overexpression showed that the differential genes such as ANPEP, KITLG, STAT5A, FOXP3, miR-451, IL-2, IL-10, IL-6, and TNF-α are mainly involved in viral and pathogens infection and the immune-inflammatory responses in PK-15 cells. This work reveals that CRNG might play a role in preventing the host from being infected by pathogens and viruses and exerting immune regulatory effects in the cytoplasm, which may be involved in prophylaxis of cyadox in piglets.

Cyadox regulates the transcription of different genes by activation of the PI3K signaling pathway in porcine primary hepatocytes

Cyadox, a new derivative of quinoxalines, has been ascertained as an antibiotic with significant growth promoting, low poison, quick absorption, swift elimination, brief residual period, and noncumulative effect. Seven differential expressed genes, including Insulin-like Growth Factor-1 ( IGF-1), Epidermal Growth Factor ( EGF), Poly ADP-ribose polymerase ( PARP), the Defender Against Apoptotic Death 1 ( DAD1), Complement Component 3 ( C3), Transketolase ( TK) and a New gene, were induced by cyadox in swine liver tissues by messenger RNA differential display reverse transcription polymerase chain reaction (DDRT-PCR) in our laboratory. However, the signal mechanism that cyadox altered these genes expression is not completely elucidated. The signaling pathways involved in the expressions of seven genes induced by cyadox were determined in porcine primary hepatocytes by RT-qPCR and the application of various signal pathway inhibitors. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that cyadox could stimulate proliferation of porcine primary hepatocytes in a time-dependent manner. In porcine primary cultured hepatocytes, phosphoinositide 3-kinase (PI3K) and transforming growth factor-β (TGF-β) signal pathways were the main signal pathways involved in the expressions of seven genes induced by cyadox. Taken together, these results demonstrate for the first time that seven cyadox-related genes expressions in porcine primary hepatocytes treated with cyadox are mediated mainly through the PI3K signaling pathway, potentially leading to enhanced cell growth and cell immunity. EGF might be the early response gene of cyadox, and a primary regulator of the other gene expressions such as IGF-1 and DAD1, playing an important role in cell proliferation promoted by cyadox.

JNK signaling in cancer cell survival

c-Jun N-terminal kinase (JNK) is involved in cancer cell apoptosis; however, emerging evidence indicates that this Janus signaling promotes cancer cell survival. JNK acts synergistically with NF-κB, JAK/STAT, and other signaling molecules to exert a survival function. JNK positively regulates autophagy to counteract apoptosis, and its effect on autophagy is related to the development of chemotherapeutic resistance. The prosurvival effect of JNK may involve an immune evasion mechanism mediated by transforming growth factor-β, toll-like receptors, interferon-γ, and autophagy, as well as compensatory JNK-dependent cell proliferation. The present review focuses on recent advances in understanding the prosurvival function of JNK and its role in tumor development and chemoresistance, including a comprehensive analysis of the molecular mechanisms underlying JNK-mediated cancer cell survival. There is a focus on the specific "Yin and Yang" functions of JNK1 and JNK2 in the regulation of cancer cell survival. We highlight recent advances in our knowledge of the roles of JNK in cancer cell survival, which may provide insight into the distinct functions of JNK in cancer and its potential for cancer therapy.

Autophagy and Apoptosis Interact to Modulate T-2 Toxin-Induced Toxicity in Liver Cells

T-2 toxin is a mycotoxin generated by Fusarium species which has been shown to be highly toxic to human and animals. T-2 toxin induces apoptosis in various tissues/organs. Apoptosis and autophagy are two closely interconnected processes, which are important for maintaining physiological homeostasis as well as pathogenesis. Here, for the first time, we demonstrated that T-2 toxins induce autophagy in human liver cells (L02). We demonstrated that T-2 toxin induce acidic vesicular organelles formation, concomitant with the alterations in p62/SQSTM1 and LC3-phosphatidylethanolamine conjugate (LC3-II) and the enhancement of the autophagic flux. Using mRFP-GFP-LC3 by lentiviral transduction, we showed T-2 toxin-mediated lysosomal fusion and the formation of autophagosomes in L02 cells. The formation of autophagosomes was further confirmed by transmission electron microcopy. While T-2 toxin induced both autophagy and apoptosis, autophagy appears to be a leading event in the response to T-2 toxin treatment, reflecting its protective role in cells against cellular damage. Activating autophagy by rapamycin (RAPA) inhibited apoptosis, while suppressing autophagy by chloroquine greatly enhanced the T-2 toxin-induced apoptosis, suggesting the crosstalk between autophagy and apoptosis. Taken together, these results indicate that autophagy plays a role in protecting cells from T-2 toxin-induced apoptosis suggesting that autophagy may be manipulated for the alleviation of toxic responses induced by T-2 toxin.