NF-κB/p53-activated inflammatory response involves in diquat-induced mitochondrial dysfunction and apoptosis

Vascular endothelium, a promising target for effectively treating fulminant diquat intoxication?

Following the withdrawal of paraquat, diquat (DQ) has emerged as the predominant herbicide. When people come into contact with or ingest DQ, may lead to poisoning and potentially fatal outcomes. Reports suggest that the mortality of DQ poisoning can be as high as 50%. DQ poisoning can be categorized as mild, moderate or severe. In cases of severe poisoning, victims often succumb to multiple organ failure within 48 h. This presents a significant challenge in the clinical management. Scholars have discovered that oxidative stress, inflammatory injury, and cell apoptosis play crucial roles in the DQ poisoning. However, the underlying connection of the extensive organ damage remains unknown. The abnormal function and activity of endothelial cells (EC) should play a crucial role in tissue damage caused by DQ due to rich microcirculation and high sensitivity to perfusion in the vulnerable organs. However, reports on DQ-induced EC injury is rare. We made a significant discovery-the presence of severe vascular endothelial damage in the kidneys and lungs affected by DQ. Therefore, we hypothesize that DQ poisoning may be attributed to oxidative stress damage and cell apoptosis in EC, ultimately resulting in multiple organ failure.

Vascular endothelium, a promising target for effectively treating fulminant diquat intoxication?

Following the withdrawal of paraquat, diquat (DQ) has emerged as the predominant herbicide. When people come into contact with or ingest DQ, may lead to poisoning and potentially fatal outcomes. Reports suggest that the mortality of DQ poisoning can be as high as 50%. DQ poisoning can be categorized as mild, moderate to severe or fulminant. In cases of fulminant poisoning, victims often succumb to multiple organ failure within 48 h. This presents a significant challenge in the clinical management. Scholars have discovered that oxidative stress, inflammatory injury, and cell apoptosis play crucial roles in the DQ poisoning. However, the underlying connection of the extensive organ damage remains unknown. The abnormal function and activity of endothelial cells (EC) should play a crucial role in tissue damage caused by DQ due to rich microcirculation and high sensitivity to perfusion in the vulnerable organs. However, reports on DQ-induced EC injury is rare. We made a preliminary discovery-the presence of severe vascular endothelial damage in the kidneys and lungs affected by DQ. Therefore, we hypothesize that DQ poisoning may be attributed to EC damage, ultimately resulting in multiple organ failure.

Two cases of diquat poisoning in adolescent children

Diquat (DQ) is among the most widely used herbicides, and its intake can cause severe systemic toxicity that manifests rapidly. The resultant symptoms can cause the dysfunction of a range of tissues and organs,. As there is no specific antidote for diquat poisoning and the efficacy of extant treatments is suboptimal, physicians must acquire a more comprehensive understanding of the most effective approaches to managing affected patients. Relative few studies have been published to date focused on diquat poisoning in pediatric patients. In this report, we compare two similar cases of juvenile diquat poisoning with dynamic changes in clinical manifestations, laboratory values, and imaging results. For the first time, the difference in whether to perform blood flow perfusion and the time difference of initiation of hemoperfusion had a clear clinical difference in the subsequent effects of diquat poisoning in children with diquat poisoning. Limited evidence is available regarding the efficacy of early hemoperfusion for diquat poisoning; however, the differences in clinical outcomes articulated here highlight the benefits of early and timely hemoperfusion therapy in the treatment of DQ toxicity in children, in conjunction with primary supportive care in the management of DQ poisoning in children.

Imaging Findings and Toxicological Mechanisms of Nervous System Injury Caused by Diquat

Diquat (DQ) is a nonselective bipyridine herbicide with a structure resembling paraquat (PQ). In recent years, the utilization of DQ as a substitute for PQ has grown, leading to an increase in DQ poisoning cases. While the toxicity mechanism of DQ remains unclear, it is primarily attributed to the intracellular generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) through the process of reduction oxidation. This results in oxidative stress, leading to a cascade of clinical symptoms. Notably, recent reports on DQ poisoning have highlighted a concerning trend: an upsurge in cases involving neurological damage caused by DQ poisoning. These patients often present with severe illness and a high mortality rate, with no effective treatment available thus far. Imaging findings from these cases have shown that neurological damage tends to concentrate on the brainstem. However, the specific mechanisms behind this poisoning remain unclear, and no specific antidote exists. This review summarizes the research progress on DQ poisoning and explores potential mechanisms. By shedding light on the nerve damage associated with DQ poisoning, we hope to raise awareness, propose new avenues for investigating the mechanisms of DQ poisoning, and lay the groundwork for the development of treatment strategies for DQ poisoning. Trial registration number: 2024PS174K.

Trimethyltin chloride induces apoptosis and DNA damage via ROS/NF-κB in grass carp liver cells causing immune dysfunction

Trimethyltin chloride (TMT), a common component in fungicides and plastic stabilizers, presents environmental risks, particularly to fish farming. The precise toxicological mechanisms of TMT in L8824 grass carp liver cells remain undefined. Our study investigates TMT's effects on these cells, focusing on its potential to induce hepatotoxicity via oxidative stress and NF-κB pathway activation. First, we selected 0, 3, 6, and 12 μM as the challenge doses, according to the inhibitory concentration of 50% (IC50) of TMT. Our results demonstrate that TMT decreases cell viability dose-dependently and triggers oxidative stress, as evidenced by increased ROS staining and MDA content. Concurrently, it inhibited the antioxidant activities of T-AOC, T-SOD, CAT, and GSH. The activation of the NF-κB pathway was confirmed by gene expression changes. Furthermore, we observed an increase in cell apoptosis rate by AO/EB staining and cell flow cytometry, and the downregulation of Bcl-2 and the upregulation of Bax, Cytc, Caspase-9, and casp3 verified that TMT passed through the BCL2/BAX/casp3 pathway induces apoptosis. DNA damage was validated by the comet assay and γH2AX gene overexpression. Lastly, our data showed increased expression of TNF-α, IL-1β, IL-6, and INF-γ and decreased antimicrobial peptides, validating immune dysfunction. In conclusion, our findings establish that TMT induces apoptosis and DNA damage via ROS/NF-κB in grass carp liver cells, causing immune dysfunction. This study provides novel insights into the toxicology research of TMT and sheds light on the immunological effects of TMT toxicity, enriching our understanding of the immunotoxicity of TMT on aquatic organisms and contributing to the protection of ecosystems.

Pesticide-Induced Inflammation at a Glance

The increasing number of studies reporting the risks of the exposure to pesticides aligned with the intensified use of such hazardous chemicals has emerged as a pressing contemporary issue, notably due to the potential effects to both the environment and human health. Pesticides, while broadly applied in modern agriculture for pest control and crop protection, have raised concerns due to their unintended effects on non-target organisms. The immune system exerts a key role in the protection against the exposome, which could result in cellular imbalances and tissue damage through the inflammatory response. Pesticides, which encompass a diverse array of chemicals, have been linked to inflammation in experimental models. Therefore, the aim of this review is to discuss the increasing concern over the risks of pesticide exposure focusing on the effects of various chemical classes on inflammation by covering, as broadly as possible, different experimental approaches as well as the multiple or co-exposure of pesticides. Overall, pesticides potentially induce inflammation in different experimental models, manifested through skin irritation, respiratory impairment, or systemic effects. The connection between pesticides and inflammation highlights the importance of proper handling and regulation of these substances and underscores the need for research into safer and sustainable practices to reduce our reliance on synthetic pesticides and fertilizers.

Analysis of Human microRNA Expression Profiling During Diquat-Induced Renal Proximal Tubular Epithelial Cell Injury

Background

We established a diquat-induced human kidney-2 cells (HK-2 cells) apoptosis model in this study to identify differentially expressed microRNAs (miRNAs) and signaling pathways involved in diquat poisoning via gene sequencing and bioinformatics analysis and explored the related therapeutic benefits.

Methods

The effects of diquat on the viability and apoptosis of HK-2 cells were explored using the CCK-8 and Annexin V-FITC/PI double staining methods. Total RNAs were extracted using the TRizol method and detected by Illumina HiSeq 2500. Bioinformatics analysis was performed to explore differentially expressed (DE) miRNAs, their enriched biological processes, pathways, and potential target genes. The RT-qPCR method was used to verify the reliability of the results.

Results

Diquat led to HK-2 cell injury and apoptosis played an important role, hence an HK-2 cell apoptosis model in diquat poisoning was established. Thirty-six DE miRNAs were screened in diquat-treated HK-2 cells. The enriched biological process terms were mainly cell growth, regulation of apoptotic signaling pathway, extrinsic apoptotic signaling pathway, and Ras protein signal transduction. The enriched cellular components were mainly cell-cell junction, cell-substrate junction, ubiquitin ligase complex, and protein kinase complex. The enriched molecular functions were mainly Ras GTPase binding, ubiquitin-like protein transferase activity, DNA-binding transcription factor binding, ubiquitin-protein transferase activity, nucleoside-triphosphatase regulator activity, transcription coactivator activity, and ubiquitin-like protein ligase binding. Signaling pathways such as MAPK, FoxO, Ras, PIK3-Akt, and Wnt were also enriched.

Conclusion

These findings aid in understanding the mechanisms of diquat poisoning and the related pathways, where DE miRNAs serve as targets for gene therapy.

Metabolomics profile of plasma in acute diquat-poisoned patients using gas chromatography-mass spectrometry

Diquat (DQ) has been confirmed to be toxic to humans and responsible for severe health impairment. While to date, very little is known about the toxicological mechanisms of DQ. Thus, investigations to discover the toxic targets and potential biomarkers of DQ poisoning are urgently needed. In this study, a metabolic profiling analysis was conducted to reveal the changes of metabolites of plasma and find out the potential biomarkers of DQ intoxication by GC-MS. First, multivariate statistical analysis demonstrated that acute DQ poisoning can lead to metabolomic changes in human plasma. Then, metabolomics studies showed that 31 of the identified metabolites were significantly altered by DQ. Pathway analysis indicated that three primarily metabolic pathways including phenylalanine, tyrosine and tryptophan biosynthesis, taurine and hypotaurine metabolism, and phenylalanine metabolism were affected by DQ, resulting in the perturbations of phenylalanine, tyrosine, taurine, and cysteine. Finally, the results of receiver operating characteristic analysis showed the above four metabolites could be used as reliable tools for the diagnosis and severity assessments of DQ intoxication. These data provided the theoretical basis for basic research to understand the potential mechanisms of DQ poisoning, and also identified the desirable biomarkers with great potential for clinical applications.

Luteoloside Prevents Sevoflurane-induced Cognitive Dysfunction in Aged Rats via Maintaining Mitochondrial Function and Dynamics in Hippocampal Neurons

Postoperative cognitive dysfunction (POCD) is characterized by impaired cognitive function, such as decreased learning and memory after anesthesia and surgery. This study aimed to explore the effect of luteoloside, a flavonoid extracted from natural herbs, on sevoflurane-induced cognitive dysfunction. Aged Sprague-Dawley male rats (20 months old) were treated with luteoloside for 7 days prior to sevoflurane exposure. After evaluation using an open field, novel object recognition, and Y-maze tests, it was determined that luteoloside effectively prevented sevoflurane-induced cognitive dysfunction. Sevoflurane exposure led to hippocampal neuron apoptosis in vivo (n = 6) and in vitro (n = 3), while this injury was prevented by luteoloside in a dose-dependent manner. Mechanistically, luteoloside maintained mitochondrial function and dynamics, as evidenced by the restored adenosine triphosphate (ATP) production and mitochondrial membrane potential as well as the upregulated levels of mitochondrial fission (optic atrophy protein 1 (Opa1) and mitofusin1 (Mfn1)) and downregulated mitochondrial fusion (mitochondrial fission 1 (Fisl) and dynamin-related protein 1 (Drp1)) factors. Notably, silencing Opa1 blocked the protective effect of luteoloside on hippocampal neurons and mitochondrial function. In summary, luteoloside prevented sevoflurane-induced cognitive dysfunction in aged rats, which may be achieved by regulating mitochondrial dynamics. Our study reveals the potential of luteoloside in preventing POCD in aged patients.

Melatonin Ameliorates Diquat-Induced Testicular Toxicity via Reducing Oxidative Stress, Inhibiting Apoptosis, and Maintaining the Integrity of Blood-Testis Barrier in Mice

Diquat is a fast, potent, and widely used bipyridine herbicide in agriculture and it induces oxidative stress in several animal models. However, its genotoxic effects on the male reproductive system remain unclear. Melatonin is an effective free-radical scavenger, which has antioxidant and anti-apoptotic properties and can protect the testes against oxidative damage. This study aimed to investigate the therapeutic effects of melatonin on diquat-induced testicular injury in mice. The results showed melatonin treatment alleviated diquat-induced testicular injury, including inhibited spermatogenesis, increased sperm malformations, declined testosterone level and decreased fertility. Specifically, melatonin therapy countered diquat-induced oxidative stress by increasing production of the antioxidant enzymes GPX1 and SOD1. Melatonin treatment also attenuated diquat-induced spermatogonia apoptosis in vivo and in vitro by modulating the expression of apoptosis-related proteins, including P53, Cleaved-Caspase3, and Bax/Bcl2. Moreover, melatonin restored the blood-testicular barrier by promoting the expression of Sertoli cell junction proteins and maintaining the ordered distribution of ZO-1. These findings indicate that melatonin protects the testes against diquat-induced damage by reducing oxidative stress, inhibiting apoptosis, and maintaining the integrity of the blood-testis barrier in mice. This study provides a theoretical basis for further research to protect male reproductive health from agricultural pesticides.

Case report: Successful outcome of a young patient with rhabdomyolysis and shock caused by diquat poisoning

The widespread use of diquat as a substitute for paraquat has led to an increase in poisoning deaths. A successful case of diquat poisoning complicated with rhabdomyolysis and shock was lacking. A 13-year-old previously healthy girl ingested 40 ml of diquat solution in a suicide attempt. The concentration of diquat in serum was 436.2 ug/L at 10 h after poisoning. The clinical course was characterized by progressive multi-organ dysfunction, particularly rhabdomyolysis and shock. The main treatments included intensive hemoperfusion combined with continuous renal replacement therapy (CRRT), drainage, and activated carbon adsorption. Meanwhile, accurate dilatation under the model of pulse indicator continuous cardiac output (PICCO) was essential for the successful treatment of shock. The serum concentration of diquat declined to 20 ug/L after 96 h of treatments. The patient was discharged from the hospital after 3 weeks of treatment without obvious symptoms. So far, this was the first successful case of diquat poisoning complicated with rhabdomyolysis and shock, which would enrich the experience of diquat poisoning treatment.

A comprehensive and mechanistic review on protective effects of kaempferol against natural and chemical toxins: Role of NF-κB inhibition and Nrf2 activation

Different toxins, including chemicals and natural, can be entered from various routes and influence human health. Herbal medicines and their active components can attenuate the toxicity of agents via multiple mechanisms. For example, kaempferol, as a flavonoid, can be found in fruits and vegetables, and has an essential role in improving disorders such as cardiovascular disorders, neurological diseases, cancer, pain, and inflammation situations. The beneficial effects of kaempferol may be related to the inhibition of oxidative stress, attenuation of inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2) and nuclear factor ĸB (NF-ĸB) as well as the modulation of apoptosis and mitogen-activated protein kinase (MAPK) signaling pathways. This flavonoid boasts a wide spectrum of toxin targeting effects in tissue fibrosis, inflammation, and oxidative stress thus shows promising protective effects against natural and chemical toxin induced hepatotoxicity, nephrotoxicity, cardiotoxicity, neurotoxicity, lung, and intestinal in the in vitro and in vivo setting. The most remarkable aspect of kaempferol is that it does not focus its efforts on just one organ or one molecular pathway. Although its significance as a treatment option remains questionable and requires more clinical studies, it seems to be a low-risk therapeutic option. It is crucial to emphasize that kaempferol's poor bioavailability is a significant barrier to its use as a therapeutic option. Nanotechnology can be a promising way to overcome this challenge, reviving optimism in using kaempferol as a viable treatment agent against toxin-induced disorders.

Case series: Diquat poisoning with acute kidney failure, myocardial damage, and rhabdomyolysis

Diquat is a herbicide that can have deleterious effects on the kidneys, liver, heart, lungs, and central nervous system on ingestion. Diquat poisoning-associated rhabdomyolysis has rarely been reported. We describe two cases of diquat poisoning with acute renal failure, myocardial damage, and rhabdomyolysis. Case 1: A 17-year-old man experienced anuria after ingesting ~200 mL of diquat 16 h prior. On admission, his creatinine (400 μmol/L), urea (11.7 mmol/L), creatine kinase (2,534 IU/L), and myohemoglobin (4,425 ng/mL) concentrations were elevated. Case 2: An 18-year-old woman who ingested ~200 mL of diquat 5.5 h prior to admission had normal creatinine, urea, and creatine kinase concentrations. Eleven hours after ingestion, she developed anuria with elevated creatinine (169 μmol/L) concentration; her creatine kinase (13,617 IU/L) and myohemoglobin (>3,811 ng/mL) concentrations were remarkably elevated 24 h after ingestion. Both patients also had elevated aminotransferase and myocardial enzyme concentrations. After undergoing hemoperfusion and hemofiltration, blood diquat concentrations in cases 1 and 2 on admission (16/6 h after ingestion), after hemoperfusion (20/11 h after ingestion), and after 8 h of hemofiltration/8 h of hemofiltration and 2 h of hemoperfusion (29/21 h after ingestion) were 4.9/9.1, 3.4/5.4, and 1.5/1.2 μg/mL, respectively. Severe diquat poisoning can cause acute kidney failure and rhabdomyolysis. Rhabdomyolysis may induce myocardial injury, aggravating kidney damage, and also increase transaminase concentration. Hemoperfusion and hemofiltration could be effective treatments for eliminating diquat in the blood.

Cyclooxygenase-2 activates the free radical-mediated apoptosis of polymorphonuclear leukocytes in the maneb- and paraquat-intoxicated rats

Overproduction of free radicals and inflammation could lead to maneb (MB)- and paraquat (PQ)-induced toxicity in the polymorphonuclear leukocytes (PMNs). Cyclooxygenase-2 (COX-2), an inducible COX, is imperative in the pesticides-induced pathological alterations. However, its role in MB- and PQ-induced toxicity in the PMNs is not yet clearly deciphered. The current study explored the contribution of COX-2 in MB- and PQ-induced toxicity in the PMNs and the mechanism involved therein. Combined MB and PQ augmented the production of free radicals, lipid peroxides and activity of superoxide dismutase (SOD) in the rat PMNs. While combined MB and PQ elevated the expression of COX-2 protein, activation of nuclear factor-kappa B (NF-κB) and phosphorylation of c-Jun N-terminal kinase (JNK), release of mitochondrial cytochrome c and levels of procaspase-3/9 were attenuated in the PMNs. Celecoxib (CXB), a COX-2 inhibitor, ameliorated the combined MB and PQ-induced modulations in the PMNs. MB and PQ augmented the free radical generation, COX-2 protein expression, NF-κB activation and JNK phosphorylation and reduced the cell viability of cultured rat PMNs and human leukemic HL60. MB and PQ elevated mitochondrial cytochrome c release and poly (ADP-ribose) polymerase cleavage whilst procaspase-3/9 levels were attenuated in the cultured PMNs. MB and PQ also increased the levels of phosphorylated c-jun and caspase-3 activity in the HL60 cells. CXB; SP600125, a JNK-inhibitor and pyrrolidine dithiocarbamate (PDTC), a NF-κB inhibitor, rescued from MB and PQ-induced changes in the PMNs and HL60 cells. However, CXB offered the maximum protection among the three. The results show that COX-2 activates apoptosis in the PMNs following MB and PQ intoxication, which could be linked to NF-κB and JNK signaling.

Progesterone as an Anti-Inflammatory Drug and Immunomodulator: New Aspects in Hormonal Regulation of the Inflammation

The specific regulation of inflammatory processes by steroid hormones has been actively studied in recent years, especially by progesterone (P₄) and progestins. The mechanisms of the anti-inflammatory and immunomodulatory P₄ action are not fully clear. The anti-inflammatory effects of P₄ can be defined as nonspecific, associated with the inhibition of NF-κB and COX, as well as the inhibition of prostaglandin synthesis, or as specific, associated with the regulation of T-cell activation, the regulation of the production of pro- and anti-inflammatory cytokines, and the phenomenon of immune tolerance. The specific anti-inflammatory effects of P₄ and its derivatives (progestins) can also include the inhibition of proliferative signaling pathways and the antagonistic action against estrogen receptor beta-mediated signaling as a proinflammatory and mitogenic factor. The anti-inflammatory action of P₄ is accomplished through the participation of progesterone receptor (PR) chaperones HSP90, as well as immunophilins FKBP51 and FKBP52, which are the validated targets of clinically approved immunosuppressive drugs. The immunomodulatory and anti-inflammatory effects of HSP90 inhibitors, tacrolimus and cyclosporine, are manifested, among other factors, due to their participation in the formation of an active ligand–receptor complex of P₄ and their interaction with its constituent immunophilins. Pharmacological agents such as HSP90 inhibitors can restore the lost anti-inflammatory effect of glucocorticoids and P₄ in chronic inflammatory and autoimmune diseases. By regulating the activity of FKBP51 and FKBP52, it is possible to increase or decrease hormonal signaling, as well as restore it during the development of hormone resistance. The combined action of immunophilin suppressors with steroid hormones may be a promising strategy in the treatment of chronic inflammatory and autoimmune diseases, including endometriosis, stress-related disorders, rheumatoid arthritis, and miscarriages. Presumably, the hormone receptor- and immunophilin-targeted drugs may act synergistically, allowing for a lower dose of each.

Perisciatic Nerve Dexmedetomidine Alleviates Spinal Oxidative Stress and Improves Peripheral Mitochondrial Dynamic Equilibrium in a Neuropathic Pain Mouse Model in an AMPK-Dependent Manner

Neuropathic pain (NPP) is a debilitating clinical condition that presently has few effective treatments. NPP is caused by uncontrolled central oxidative stress and inflammation. Preliminary studies indicate that dexmedetomidine (DEX), an agonist of the alpha-2 adrenergic receptor, is beneficial for treating NPP. In this paper, the effects of administering DEX around injured nerves in a chronic constriction injury- (CCI-) induced neuropathic pain mouse model are investigated. According to the results, the perineural DEX significantly reversed the decline in the mechanical threshold and thermal latency in CCI mice ( $p<0.001$ ). In the peripherally affected ischiadic nerve, the perineuronal DEX upregulated the expressions of pAMPK, OPA1, and SNPH but not Drp1 or KIF5B. The aforementioned effects of administering DEX can be partially reversed by compound C, a selective and reversible inhibitor of AMP-activated protein kinase (AMPK). Furthermore, it was found that perineural DEX significantly inhibited the CCI-induced upregulation of the immediate early gene c-Fos, overexpression of the inflammatory factors tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), attenuation of the NADH dehydrogenase complexes I, II, III, and IV, and the repression of ATP, SOD, and GSH in the dorsal horn of the spinal cord (DHSC) ( $p<0.01$ ). These findings indicate that perineuronal DEX protected the injured ischiadic nerves and attenuated neuropathic pain via AMPK activation to improve energy supply in the peripheral injured nerves, alleviate the inflammatory factor release, and inhibit oxidative stress in the DHSC.

NF-κB-upregulated miR-155-5p promotes hepatocyte mitochondrial dysfunction to accelerate the development of nonalcoholic fatty liver disease through downregulation of STC1

Previous studies have highlighted the involvement of nuclear factor kappa B (NF-κB) in the development of nonalcoholic fatty liver disease (NAFLD). The purpose of our investigation is to explore the interaction among NF-κB, microRNA-155-5p (miR-155-5p), and Stanniocalcin 1 (STC1), and its effects on NAFLD by establishing a NAFLD model in Sprague Dawley rats. A highly-expressed miR-155-5p and NF-κB was revealed in the liver tissues of NAFLD rats, and a positive correlation was identified between miR-155-5p and NF-κB. Next, the expression of NF-κB and STC1 was altered in the modeled rats through lentivirus injection, followed by determination on the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol, triglycerides, and low-density lipoprotein cholesterol. Furthermore, the hepatocyte mitochondria were separated to measure the activities of adenosine triphosphate (ATP), reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and mitochondrial respiratory chain complex, and to observe the number, length and ultrastructural length of mitochondrial cristae. The results demonstrated that NF-κB overexpression induced mitochondrial dysfunction, increased ROS level, decreased ATP and MMP contents, as well as inhibited the number and length of mitochondrial cristae in the hepatocyte mitochondria of NAFLD rats. Besides, miR-155-5p was found to negatively regulate STC1 expression based on dual luciferase reporter gene assay, which exert inhibition on mitochondrial activity of hepatocytes in NAFLD rats. These results uncover the possible involvement of NF-κB/miR-155-5p/STC1 axis in NAFLD progression, that NF-κB could increase miR-155-5p expression to inhibit STC1 expression, thus inducing hepatic mitochondrial dysfunction and promoting the occurrence and development of NAFLD.

Pre-Exposure to Environmental Enrichment Protects against Learning and Memory Deficits Caused by Infrasound Exposure

With the development of industrialization in recent years, infrasound has become an important component of public noise. To date, diverse studies have revealed the negative effects of infrasound on the central nervous system (CNS), especially the learning and memory ability. It is widely reported that environmental enrichment (EE) ameliorates the learning and memory deficits in different models of brain injury. Therefore, the present study was designed to determine the possible benefits of pre-exposure to EE in preventing functional deficits following infrasound exposure and their related mechanism. Adult male rats were given enriched or standard housing for 30 days. Following enrichment, the rats were exposed to 16 Hz, 130 dB infrasound for 14 days, and then their learning and memory ability was assessed. Changes to neuroinflammation, apoptosis, and oxidative stress in the hippocampus were also detected. Our results showed that the infrasound-induced deficit in learning and memory was attenuated significantly in EE pre-exposed rats. Pre-exposure to EE could induce a decrease in proinflammatory cytokines and increased anti-inflammatory cytokines and antioxidant properties in the hippocampus. Moreover, pre-exposure to EE also exerted antiapoptosis functions by upregulating the B-cell lymphoma/leukemia-2 (Bcl-2) level and downregulating the P53 level in the hippocampus. In conclusion, the results of the present study suggested that EE is neuroprotective when applied before infrasound exposure, resulting in an improved learning and memory ability by enhancing antioxidant, anti-inflammatory, and antiapoptosis capacities.

Tea polyphenols alleviates acetochlor-induced apoptosis and necroptosis via ROS/MAPK/NF-κB signaling in Ctenopharyngodon idellus kidney cells

Overuse of acetochlor pollutes soil and rivers, causing threats to the ecosystem. Studies found that acetochlor exposure could damage multiple organs and tissues in fish and mammal. Tea polyphenols (TP), a natural antioxidant that extracted from tea, has been widely used in food and feed additions. However, the mechanism by which acetochlor causes tissue damage is unclear, and its mitigating agent has yet to be developed. Therefore, we established acetochlor exposure and TP mitigation models by treating Ctenopharyngodon idellus kidney (CIK) cells with 20 μM acetochlor and/or 2.5 μg/mL TP for 24 h, and detected the programmed cell death and its related pathways. The results showed that acetochlor exposure modified antioxidant enzyme activities, induced oxidative stress, resulted in the decline of MMP and ATP levels, enhanced glycolysis and lactate accumulation, and triggered apoptosis and necroptosis in CIK cells. However, TP could inhibit CYP450s expression, activate Nrf2 pathway, enhance antioxidant capacity, further effectively alleviate acetochlor-induced CIK cell death. Overall, the present study proved that acetochlor exposure triggered mitochondrial damage and lactate accumulation-mediated apoptosis and necroptosis through CYP450s/ROS/MAPK/NF-κB pathway. Furthermore, TP could alleviate effectively cell death through relieving oxidative stress and lightening Warburg-like effect.

Identification of differentially expressed genes and pathways in diquat and paraquat poisoning using bioinformatics analysis

[Objective] In this study, differentially expressed genes (DEGs) and signaling pathways involved in diquat (DQ) and paraquat (PQ) poisoning were identified via bioinformatics analysis, in order to inform the development of novel clinical treatments. [Methods] Raw data from GSE153959 were downloaded from the Gene Expression Omnibus database. DEGs of the DQ vs. control (CON) and PQ vs. CON comparison groups were identified using R, and DEGs shared by the two groups were identified using TBtools. Subsequently, the shared DEGs were searched in the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, using the Database for Annotation, Visualization, and Integrated Discovery. A protein-protein interaction (PPI) network was constructed, and hub genes were identified using the cytoHubba plug-in in Cytoscape software. Finally, Circos and contrast plots showing the DEGs shared between mouse and human chromosomes were constructed using TBtools. [Results] Thirty- one DEGs shared by the DQ and PQ groups were identified. Enriched biological process terms included positive regulation of cell proliferation and translation. Enriched cellular component terms included extracellular region, intracellular membrane- bounded organelle and mitochondrion. Enriched molecular function terms included transcription factor activity and sequence-specific double-stranded DNA binding. Enriched KEGG pathways included the interleukin- 17 signaling pathway, tumor necrosis factor signaling pathway, and human T- cell leukemia virus 1 infection. The top ten hub genes in the PPI network were Ptgs2, Cxcl2, Csf2, Mmp13, Areg, Plaur, Fosl1, Ereg, Atf3, and Tfrc. Cxcl2, Csf2, and Atf3 played important roles in the mitogen- activated protein kinase signaling pathway. [Conclusions] These pathways and DEGs may serve as targets for gene therapy.

Chaperon-mediated autophagy can regulate diquat-induced apoptosis by inhibiting α-synuclein accumulation cooperatively with macroautophagy

α-Synuclein, which is associated with Parkinson's disease, is cleared by the ubiquitin-proteasome system and autophagy lysosome system. Chaperon-mediated autophagy (CMA) and macroautophagy are major subtypes of autophagy and play a critical role in pesticide-induced α-synucleinopathy. In this study, we explored the role of CMA in diquat (DQ)-induced α-synucleinopathy and characterized the relationship between CMA and macroautophagy in the clearance of pathologic α-synuclein for the prevention of DQ neurotoxicity. DQ was cytotoxic to SH-SY5Y cells in a concentration-dependent manner, as shown by decreased cell viability and increased cytotoxicity. DQ treatment was also found to induce autophagy such as CMA and macroautophagy by monitoring the expression of Lamp2A and microtubule-associated protein 1A/1B light chain 3B (LC3-II) respectively. Following DQ treatment, SH-SY5Y cells were found to have induced phosphorylated and detergent-insoluble α-synuclein deposits, and MG132, a proteasome inhibitor, effectively potentiated both CMA and macroautophagy for preventing α-synuclein aggregation. Interestingly, CMA impairment by Lamp2A-knock down decreased the LC3II expression compared to in DQ-treated cells transfected with control siRNA. In Lamp2-knock down cells, pathologic α-synuclein was increased 12 h after DQ treatment, but there was no change observed at 24 h. In DQ-treated cells, macroautophagy by 3-methyladenine and bafilomycin inhibition increased Lamp2A expression, indicating an increase in CMA activity. In addition, CMA modulation affected apoptosis, and inhibiting lysosome activity by NH₄Cl increased apoptosis in DQ-treated cells. An increase in autophagy was confirmed to compensate for the decrease in lysosome activity. Pretreatment with z-VAD-fmk, a pan-caspase inhibitor, significantly enhanced the macroautophagy response of DQ-exposed cells without alterations in Lamp2A expression. Our results suggest that CMA can regulate DQ-induced α-synucleinopathy cooperatively with macroautophagy, and crosstalk between macroautophagy and CMA plays an important role in DQ-induced cytotoxicity. Taken together, autophagy modulation may be a useful treatment strategy in pesticide-induced neurodegenerative disorders through preventing α-synucleinopathy.

Th17/IL-17 induces endothelial cell senescence via activation of NF-κB/p53/Rb signaling pathway

Cellular senescence is a key mechanism of age-related vascular endothelial dysfunction. Interleukin-17A (IL-17A) is an inflammatory cytokine produced by Th17 cells (a subgroup of helper T cells), which is a key factor in the development of atherosclerosis. However, the effect of IL-17A on the senescence of vascular endothelial cells is still unclear. In this study, we aimed to explore the role of IL-17A on endothelial cell senescence and its signaling pathways associated with senescence. The proportion of Th17 cells in the spleen and the expression levels of IL-17A, IL-6, and vascular cell adhesion molecule-1 (VCAM-1) in mice of different ages were increased with aging. In vitro experiments showed that proliferation was inhibited, senescent β-galactosidase and senescence-associated proteins (p16, p19, p21, and p53) of mouse aortic endothelial cells (MAECs) were increased with IL-17A treatment. Blocking the NF-κB pathway with ammonium pyrrolidinedithiocarbamate (PDTC) successfully inhibited IL-17A-induced expression of senescence-associated proteins. In conclusion, our data reveal a previously unsuspected link between IL-17A and endothelial cell senescence, which was mediated by the NF-κB /p53/Rb pathway.

Effects of Acute Diquat Poisoning on Liver Mitochondrial Apoptosis and Autophagy in Ducks

Diquat (DQ) is an effective herbicide and is widely used in agriculture. Due to persistent and frequent applications, it can enter into aquatic ecosystem and induce toxic effects to exposed aquatic animals. The residues of DQ via food chain accumulate in different tissues of exposed animals including humans and cause adverse toxic effects. Therefore, it is crucial and important to understand the mechanisms of toxic effects of DQ in exposed animals. We used ducks as test specimens to know the effects of acute DQ poisoning on mechanisms of apoptosis and autophagy in liver tissues. Results on comparison of various indexes of visceral organs including histopathological changes, apoptosis, autophagy-related genes, and protein expression indicated the adverse effects of DQ on the liver. The results of our experimental trial showed that DQ induces non-significant toxic effects on pro-apoptotic factors like BAX, BAK1, TNF-α, caspase series, and p53. The results revealed that anti-apoptotic gene Parkin was significantly upregulated, while an upward trend was also observed for Bcl2, suggesting that involvement of the anti-apoptotic factors in ducklings plays an important role in DQ poisoning. Results showed that DQ significantly increased the protein expression level of the autophagy factor Beclin 1 in the liver. Results on key autophagy factors like LC3A, LC3B, and p62 showed an upward trend at gene level, while the protein expression level of both LC3B and p62 reduced that might be associated with process of translation affected by the pro-apoptotic components such as apoptotic protease that inhibits the occurrence of autophagy while initiating cell apoptosis. The above results indicate that DQ can induce cell autophagy and apoptosis and the exposed organism may resist the toxic effects of DQ by increasing anti-apoptotic factors.

High-dose diquat poisoning: a case report

Diquat is a widely used herbicide that is substituted for paraquat. With paraquat off the market, cases of diquat poisoning have been gradually increasing. The kidney is the most frequently impaired organ in diquat poisoning. Few cases of multiple organ failure caused by diquat have been reported.

We herein describe a 30-year-old man who orally ingested about 160 mL of enriched diquat. Despite aggressive treatment, the patient’s condition progressed to multiple organ failure and death. The pulmonary lesions in this patient were different from those previously reported. This patient did not die of renal failure but of severe respiratory failure. He exhibited three different stages of pulmonary disease.

The lung lesions in this case were unique. We hope that doctors will pay more attention to the lung lesions in patients with diquat poisoning in future and find new treatment methods to save the lives of such patients.

The p53/NF-kappaB-dependent induction of sestrin2 by amyloid-beta peptides exerts antioxidative actions in neurons

Accumulation of senile plaques mainly composed of neurotoxic amyloid-beta peptide (Aβ) is a pathological hallmark of Alzheimer's disease (AD). Sestrin2 inducible by various types of stressors is known to promote autophagy and exert antioxidative effects. In this work, we revealed the molecular mechanisms underlying Aβ induction of sestrin2 and tested whether antioxidation, in addition to autophagy regulation, also contributes to its neuroprotective effects in primary rat cortical neurons. We found that Aβ25-35 triggered nuclear translocation of p65 and p50, two subunits of nuclear factor-kappaB (NF-κB), and p53. Aβ25-35-induced sestrin2 expression was abolished by the p65 siRNA, the NF-κB inhibitor SN50, and the p53 inhibitor pifithrin-alpha (PFT-α). Further, Aβ25-35 enhanced binding of p50 and p53 to sestrin2 gene promoter that was abolished respectively by the p50 shRNA and PFT-α. Both p50 shRNA and PFT-α attenuated Aβ25-35-induced expression as well as nuclear translocation of all three transcription factors, namely p65, p50, and p53. Interestingly, p50 binding to the promoters of its target genes required p53 activity, whereas p50 also negatively regulated p53 binding to its target sequences. Suppression of sestrin2 expression by siRNA enhanced Aβ25-35- and Aβ1-42-induced production of reactive oxygen species (ROS), lipid peroxidation, and formation of 8-hydroxy-2-deoxyguanosine (8-OH-dG). In contrast, overexpression of the sestrin2 N-terminal or C-terminal fragments neutralized Aβ25-35-induced ROS production. We concluded that Aβ-induced sestrin2 contributing to antioxidant effects in neurons is in part mediated by p53 and NF-κB, which also mutually affect the expression of each other.

The high expression of miR-564 in patients with systemic lupus erythematosus promotes differentiation and maturation of DC cells by negatively regulating TP53 expression in vitro

BACKGROUND

miRNA is involved in the occurrence and progression of systemic lupus erythematosus (SLE), but the regulatory effect of miRNA on dendritic cells in SLE patients is still unclear.

MATERIAL AND METHODS

Bioinformatics methods were used to analyze the differentially expressed miRNA and its target genes in SLE patients. In vitro experiments were conducted to explore the effects and mechanisms of differentially expressed miRNAs in SLE patients on the differentiation and maturation of monocyte-derived dendritic cells.

RESULTS

Bioinformatics analysis showed that miR-564 was up-regulated in SLE patients, and TP53 was the core target gene of miR-564. The expression level of miR-564 showed a rising trend during the differentiation and maturation of monocytes into Mo-DC cells. The differentiation, maturation and proliferation of Mo-DC cells were significantly inhibited by transfection with miR-564 antagomir. The expression of TP53 is negatively regulated by miR-564. In rescue experiments, the proliferation and migration of DC cells were significantly restored by co-transfection of miR-564 antagomir and TP53 si-RNA.

CONCLUSION

Highly expressed miR-564 promotes the maturation, proliferation of Mo-DC cells by negatively regulating the expression of TP53.

Kaempferol attenuates diquat-induced oxidative damage and apoptosis in intestinal porcine epithelial cells

Kaempferol, a flavonol component of plants, is well-known to exhibit multiple bioactivities, such as anti-oxidative and anti-apoptotic effects. However, the underlying mechanisms responsible for the beneficial effects remain elusive. This study was conducted to test the hypothesis that kaempferol attenuated diquat-induced oxidative damage and intestinal barrier dysfunction by ameliorating oxidative damage and apoptosis in intestinal porcine epithelial cells. Compared with the control group, diquat treatment led to enhanced intracellular ROS production, increased mitochondrial depolarization, and apoptosis, which were accompanied by cell cycle arrest at the G1 phase, reduced cell migration, and disrupted intestinal epithelial barrier function. These effects triggered by diquat were reversed by kaempferol. Further study showed that the protective effect of kaempferol was associated with an enhanced mRNA level of genes related to cell cycle progression (cyclin D1, CDK4, and E2F1) and genes implicated in the anti-oxidant system (GSR, GSTA4, and HO-1), up-regulated abundance of tight junctions (ZO-1, ZO-2, occludin, and claudin-4), as well as enhanced Nrf2, an anti-oxidant transcription factor. In conclusion, we revealed a functional role of kaempferol in the intestinal barrier. Ingestion of kaempferol-rich foods might be a potential strategy to improve the integrity and function of enterocytes.

Adverse effects of pesticides on the functions of immune system

Pesticides are chemical substances used to kill unwanted fungi, weeds and insects. In many countries, there is currently concern regarding the adverse effects of pesticides on health. It has been reported that pesticides may cause cancer, respiratory diseases, organ diseases, system failures, nervous system disorders and asthma, which are closely connected with immune disorders. Therefore, this study reviewed the immunotoxicity of pesticides that are currently used or prohibited from being used, especially their effects on leukocytes such as T cells, B cells, NK cells and macrophages. These immune cells play crucial roles in innate and adaptive immune systems to protect hosts. Pesticides are known to have possible toxicological modes of action to induce oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress in living organisms. According to previous studies, pesticides such as atrazine (ATR), organophophorus (OP) compounds, carbamates, and pyrethroids were shown to inhibit the survival and growth of leukocytes by inducing apoptosis or cell cycle arrest and interfering with the specific immunological functions of each type of immune cells. These results suggest the immunotoxicity of pesticides toward specific immune cells. To substantiate the overall immunocompromised effects of pesticides, there is a need to collect and thoroughly analyze additional information regarding other immunological toxicities.

Piceatannol Ameliorates Hepatic Oxidative Damage and Mitochondrial Dysfunction of Weaned Piglets Challenged with Diquat

Simple Summary

In our experiment, piglets in two challenged groups were orally administrated either piceatannol or another vehicle solution, and then injected with diquat, a bipyridyl herbicide that can cause a large amount of reactive oxygen species in animal bodies and is widely used to cause oxidative stress, to investigate the effects of piceatannol on hepatic redox status, mitochondrial function and the underlying mechanism. A control group was given neither piceatannol supplementation nor diquat injection. Results showed that piceatannol could improve hepatic redox status, preserve mitochondrial function, and prevent excessive apoptosis of liver cells. In addition, piceatannol might exert its protective effects through a classic antioxidant signaling pathway named Nrf2. Our findings indicated that piceatannol might be an appropriate candidate for further development as an antioxidant food supplement to minimize the risk of oxidative stress in young animals.

Abstract

The liver is an organ that produces large amounts of reactive oxygen species (ROS). Human infants or piglets are prone to oxidative damage due to their uncompleted development of the antioxidant system, causing liver disease. Piceatannol (PIC) has been found to have significant antioxidant effects. The aim of this experiment was to investigate the effects of PIC on the liver in piglets experiencing oxidative stress caused by diquat (DQ). After weaning, 54 male piglets (Duroc × [Landrace × Yorkshire]) were selected and randomly divided into three treatment groups: the CON group, the DQ-CON group, and the DQ-PIC group. The two challenged groups were injected with DQ and then orally administrated either PIC or another vehicle solution, while the control group was given sterile saline injections and an orally administrated vehicle solution. Compared to the results of the CON group, DQ increased the percentage of apoptosis cells in the liver, also decreased the amount of reduced glutathione (GSH) and increased the concentration of malondialdehyde (MDA). In addition, the adenosine triphosphate (ATP) production, activities of mitochondrial complex I, II, III, and V, and the protein expression level of sirtuin 1 (SIRT1) were inhibited by DQ. Furthermore, PIC supplementation inhibited the apoptosis of hepatic cells caused by DQ. PIC also decreased MDA levels and increased the amount of GSH. Piglets given PIC supplementation exhibited increased activities of mitochondrial complex I, II, III, and V, the protein expression level of SIRT1, and the ATP production in the liver. In conclusion, PIC affected the liver of piglets by improving redox status, preserving mitochondrial function, and preventing excessive apoptosis.

Inhibition of p53 alleviates prostate cell apoptosis in Escherichia coli‑induced bacterial prostatitis

Previous studies demonstrated that uropathogenic Escherichia coli infection contributes to human bacterial prostatitis. Apoptosis of prostate epithelial cells is closely associated with the progression of bacterial prostatitis. The aim of the present study was to investigate the effect of cellular tumor antigen p53 (p53) on the apoptosis of bacterial prostatitis cells. The prostate epithelial RWPE‑1 cell line was infected with Escherichia coli, and treated cells and the culture supernatant were obtained at specific time points. The cell apoptosis rates, protein and mRNA of p53 were detected in the different treatment groups. Flow cytometry and terminal deoxynucleotidyl‑transferase‑mediated dUTP nick end labeling assays were used for the detection of cell apoptosis, and cell proliferation was determined by a Cell Counting Kit‑8 assay. The expression of p53 was inhibited by small interfering (si)RNA, and its mRNA and protein were detected. An ELISA was used for detecting cytokines in the culture supernatant. The result demonstrated that Escherichia coli infection led to an increase in prostate epithelial cell apoptosis (P<0.05), and resulted in increases of interleukin (IL)‑4, IL‑6 and IL‑8, and decrease in IL‑10. p53, apoptosis regulator BAX (Bax), caspase‑9 and Caspase‑3 expression were upregulated upon Escherichia coli exposure (P<0.05). Following transfection with p53 siRNA, the promotion of cell apoptosis induced by Escherichia coli infection was decreased, and the p53 and Bax protein expression were additionally decreased. Therefore, it was suggested that Escherichia coli increases cell apoptosis in bacterial prostatitis by activating the death receptor pathway involving p53. Inhibition of p53 alleviated prostate cell apoptosis induced by Escherichia coli.

NF-κB/mTOR-mediated autophagy can regulate diquat-induced apoptosis

Autophagy and apoptosis are the major types of cell death in pesticide-induced neurotoxicity, and autophagy is known to play a role in cell protection by inhibiting apoptosis. In this study, we characterized the relationship between autophagy and apoptosis in diquat (DQ)-induced cell death and explored a novel pharmacotherapeutic approach involving autophagy regulation to prevent DQ neurotoxicity. DQ was cytotoxic to PC12 cells in a concentration-dependent manner, as shown by decreased cell viability and decreased dopamine (DA) levels. DQ-induced apoptosis was found in PC12 cells, as demonstrated by activation of caspase-3 and -9 and by nuclear condensation. By monitoring expression of microtubule-associated protein 1A/1B light chain 3B (LC3-II) and p62, DQ was found to induce autophagy. Exposure of PC12 cells to DQ led to the production of reactive oxygen species (ROS), and N-acetyl-cysteine (NAC) antioxidant effectively blocked both apoptosis and autophagy. Interestingly, DQ in PC12 cells showed increased p53 and NF-κB in a time-dependent manner; furthermore, pifithrin-α (PFT-α), a p53 inhibitor, downregulates the cytotoxicity of DQ, as shown by decreased LC3-II and cleaved caspase-3. SN50, an NF-κB inhibitor, results in diminished LC3-II, cleaved caspase-3, and p53. DQ induces mitogen-activated protein kinase (MAPK) signaling including ERK, JNK, and p38, which inhibit regulated apoptosis and autophagic cell death by controlling mTOR signaling. In addition, modulation of DQ-induced apoptosis in response to autophagy regulation was investigated. Pretreatment with rapamycin, an autophagy inducer, significantly enhanced the viability of DQ-exposed cells by alleviating DQ-induced apoptosis. Conversely, cell pretreatment with 3-methyladenine (3MA), an autophagy inhibitor increased DQ toxicity. Our results suggest that DQ-induced cytotoxicity is modified by autophagy regulation. Pharmacologic induction of autophagy may be a useful treatment strategy in neurodegenerative disorders.