Inflammation response after the cessation of chronic arsenic exposure and post-treatment of natural astaxanthin in liver: potential role of cytokine-mediated cell-cell interactions

Resveratrol alleviates inorganic arsenic-induced ferroptosis in chicken brain via activation of the Nrf2 signaling pathway

Inorganic arsenic (iAs) is a well-recognized environmental pollutant that induces severe brain injury in humans and animals. The antioxidant, anti-inflammatory, and anti-ferroptotic effects of resveratrol (Res) were demonstrated in multiple animal experiments. In order to investigate the protective effect of Res on iAs-induced chicken brain injury, the 40 chickens (19-d-old, female) brain injury model was established by oral administration of iAs (30 mg/L NaAsO2) for 6 weeks. All chickens had free access to both food and water during the experiment. The biochemical indices, hematoxylin-eosin staining, and related protein levels of oxidative stress, inflammation and ferroptosis were then determined. Our results indicated that Res (1000 mg/kg) alleviated the iAs-induced brain injury after 6 weeks of oral administration, primarily by reducing the interleukin-1β mRNA expression and nuclear factor kappa B and malondialdehyde level, and increasing the antioxidant enzyme activity and the mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2). Taken together, our study demonstrates that Res effectively inhibits iAs-induced oxidative stress and ferroptosis by mediating the Nrf2 signaling pathway, thereby alleviating iAs-induced brain injury in chickens. This is the first time that the amelioration effects of Res on the iAs-induced brain have been investigated from multiple perspectives.

Dendrobium officinale polysaccharide alleviates thiacloprid-induced kidney injury in quails via activating the Nrf2/HO-1 pathway

Thiacloprid (THI) is a neonicotinoid insecticide, and its wide-ranging use has contributed to severe environmental and health problems. Dendrobium officinale polysaccharide (DOP) possesses multiple biological activities such as antioxidant and antiapoptosis effect. Although present research has shown that THI causes kidney injury, the exact molecular mechanism and treatment of THI-induced kidney injury remain unclear. The study aimed to investigate if DOP could alleviate THI-induced kidney injury and identify the potential molecular mechanism in quails. In this study, Japanese quails received DOP (200 mg/kg) daily with or without THI (4 mg/kg) exposure for 42 days. Our results showed that DOP improved hematological changes, biochemical indexes, and nephric histopathological changes induced by THI. Meanwhile, THI exposure caused oxidative stress, apoptosis, and autophagy. Furthermore, THI and DOP cotreatment significantly activated the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway, restored antioxidant enzyme activity, and reduced apoptosis and autophagy in quail kidneys. In summary, our study demonstrated that DOP mitigated THI-mediated kidney injury was associated with oxidative stress, apoptosis, and autophagy via activation of the Nrf2/HO-1 signaling pathway in quails.

Echinacea purpurea root extract mitigates hepatotoxicity, genotoxicity, and ultrastructural changes induced by hexavalent chromium via oxidative stress suppression

Environmental and occupational exposure to hexavalent chromium (CrVI) is mostly renowned as a possible hepatotoxic in mammals. Echinacea purpurea (L.) Moench, a phenolic-rich plant, is recurrently used for its therapeutic properties. Therefore, this investigation was done to explore whether E. purpurea (EP) root extract would have any potential health benefits against an acute dose of CrVI-induced oxidative damage and hepatotoxicity. Results revealed that GC-MS analysis of EP root extract has 26 identified components with a significant amount of total phenolic and flavonoid contents. Twenty-four Male Wistar rats were divided into four groups: control, EP (50 mg/kg BW/day for 21 days), CrVI (15 mg/kg BW as a single intraperitoneal dosage), and EP + CrVI, respectively. Rats treated with CrVI displayed a remarkable rise in oxidative stress markers (TBARS, H2O2, PCC), bilirubin, and lactate dehydrogenase activity, and a marked decrease in enzymatic and non-enzymatic antioxidants, transaminases, and alkaline phosphatase activities, and serum protein level. Also, CrVI administration induced apoptosis and inflammation in addition to histological and ultrastructural abnormalities in the liver tissue. The examined parameters were improved significantly in rats pretreated with EP and then intoxicated with CrVI. Conclusively, EP had a potent antioxidant activity and could be used in the modulation of CrVI-induced hepatotoxicity.

Novel findings from arsenic‑lead combined exposure in mouse testicular TM4 Sertoli cells based on transcriptomics

Arsenic (As) and lead (Pb) exist widespread in daily life, and they are common harmful substances in the environment. As and Pb pollute the environment more often in combination than in isolation. The TM4 Sertoli cell line is one of the most common normal mouse testicular Sertoli cell lines. In vitro, we found that the type of combined action of As and Pb on TM4 Sertoli cells was additive action by using the isobologram analysis. To further investigate the combined toxicity of As and Pb, we performed mRNA and miRNA sequencing on TM4 Sertoli cells exposed to As alone (4 μM NaAsO2) and AsPb combined (4 μM NaAsO2 and 150 μM PbAc), respectively. Compared with the control group, 1391 differentially expressed genes (DEGs) and 6 differentially expressed miRNAs (DEMs) were identified in the As group. Compared with the control group, 2384 DEGs and 44 DEMs were identified in the AsPb group. Compared with the As group, 387 DEGs and 4 DEMs were identified in the AsPb group. Through data analysis, we discovered for the first time that As caused the dysfunction of cholesterol synthesis and energy metabolism, and disrupted cyclic adenosine monophosphate signaling pathway and wingless/integrated (Wnt) signaling pathway in TM4 Sertoli cells. In addition to affecting cholesterol synthesis and energy metabolism, AsPb combined exposure also up-regulated the antioxidant reaction level of TM4 Sertoli cells. Meanwhile, the Wnt signaling pathway of TM4 Sertoli cells was relatively normal when exposed to AsPb. In conclusion, at the transcription level, the combined action of AsPb is not merely additive effect, but involves synergistic and antagonistic effects. The new discovery of the joint toxic mechanism of As and Pb breaks the stereotype of the combined action and provides a good theoretical basis and research clue for future study of the combined-exposure of harmful materials.

Chronic arsenic exposure-provoked biotoxicity involved in liver-microbiota-gut axis disruption in chickens based on multi-omics technologies

INTRODUCTION

Arsenic has been ranked as the most hazardous substance by the U.S. Agency for Toxic Substances and Disease Registry. Environmental arsenic exposure-evoked health risks have become a vital public health concern worldwide owing to the widespread existence of arsenic. Multi-omics is a revolutionary technique to data analysis providing an integrated view of bioinformation for comprehensively and systematically understanding the elaborate mechanism of diseases.

OBJECTIVES

This study aimed at uncovering the potential contribution of liver-microbiota-gut axis in chronic inorganic arsenic exposure-triggered biotoxicity in chickens based on multi-omics technologies.

METHODS

Forty Hy-Line W-80 laying hens were chronically exposed to sodium arsenite with a dose-dependent manner (administered with drinking water containing 10, 20, or 30 mg/L arsenic, respectively) for 42 d, followed by transcriptomics, serum non-targeted metabolome, and 16S ribosomal RNA gene sequencing accordingly.

RESULTS

Arsenic intervention induced a serious of chicken liver dysfunction, especially severe liver fibrosis, simultaneously altered ileal microbiota populations, impaired chicken intestinal barrier, further drove enterogenous lipopolysaccharides translocation via portal vein circulation aggravating liver damage. Furtherly, the injured liver disturbed bile acids (BAs) homoeostasis through strongly up-regulating the BAs synthesis key rate-limiting enzyme CYP7A1, inducing excessive serum total BAs accumulation, accompanied by the massive synthesis of primary BA-chenodeoxycholic acid. Moreover, the concentrations of secondary BAs-ursodeoxycholic acid and lithocholic acid were markedly repressed, which might involve in the repressed dehydroxylation of Ruminococcaceae and Lachnospiraceae families. Abnormal BAs metabolism in turn promoted intestinal injury, ultimately perpetuating pernicious circle in chickens. Notably, obvious depletion in the abundance of four profitable microbiota, Christensenellaceae, Ruminococcaceae, Muribaculaceae, and Faecalibacterium, were correlated tightly with this hepato-intestinal circulation process in chickens exposed to arsenic.

CONCLUSION

Our study demonstrates that chronic inorganic arsenic exposure evokes liver-microbiota-gut axis disruption in chickens and establishes a scientific basis for evaluating health risk induced by environmental pollutant arsenic.

The role of thioredoxin and glutathione systems in arsenic-induced liver injury in rats under glutathione depletion

Antioxidant systems like thioredoxin (Trx) and glutaredoxin (Grx) maintain oxidative stress balance. These systems have cross-talk supported by some in vitro studies. We investigated the underlying mechanisms of arsenic-induced liver injury in glutathione-deficient rats and whether there was any cross-talk between the Trx and Grx systems. The rats in arsenic-treated groups were administered with sodium arsenite (10, 20 mg/kg b w/d) for four weeks. In buthionine sulfoximine (BSO, an inhibitor of GSH) and 20 mg/kg arsenic combined groups, rats were injected with 2 mmol/kg BSO intraperitoneally twice per week. BSO exacerbated arsenic-induced liver injury by increasing arsenic accumulation in urine, serum, and liver while decreasing glutathione activity and resulting in upregulated mRNA expression of the Trx system and downregulation of Grx mRNA expression. The impact of Trx lasted longer than that of the Grx. The Trx system remained highly expressed, while GSH, Grx1, and Grx2 levels were decreased. The inhibitory effect of only BSO treatment on Grx1 and Grx2 was not pronounced. However, the combined impact of arsenic and BSO upregulated Trx expression, primarily related to further reduction of GSH. As a result, the suppressed Grxs were protected by the upregulated Trxs, which serve as a backup antioxidant defense system in the liver.

NaAsO2 regulates TLR4/MyD88/NF-κB signaling pathway through DNMT1/SOCS1 to cause apoptosis and inflammation in hepatic BRL-3A cells

The exact molecular mechanism of arsenic-induced liver injury has not been fully elucidated. The aim of the study was to investigate the potential mechanism of NaAsO2-induced cytotoxicity in BRL-3A cells and to provide a basis for the mechanism of arsenic poisoning. BRL-3A cells were treated with different doses of NaAsO2, DNMT1 inhibitor (DC_517), TLR4 inhibitor (TAK-242), and transfection of SOCS1 plasmid. Cell activity, apoptosis, inflammation and protein expression of DNMT1, SOCS1, TLR4, MyD88, and NF-κB were detected by CCK8 assay, Annexin V-FITC and Western blot, respectively. With increasing NaAsO2 doses, BAX and caspase-3 expression increased, Bcl-2 expression decreased, pro-inflammatory factors TNF-α, IL-1β, and IL-6 increased, and cell activity decreased causing increased apoptosis. When BRL-3A was intervened with 10, and 20 μmol/L NaAsO2, DNMT1 expression was elevated, SOCS1 expression was decreased, and TLR4, MyD88, p-IκBα/IκBα, and p-p65/p65 expression were elevated. After the combination of NaAsO2 and DC_517, compared to the NaAsO2 group, apoptosis and inflammation were attenuated, SOCS1 expression was elevated and TLR4, MyD88, p-IκBα/IκBα and p-p65/p65 expression was decreased. Apoptosis and inflammation were attenuated after co-treatment of SOCS1 high expression with NaAsO2 compared to the NaAsO2 group. In addition, TLR4, MyD88, p-IκBα/IκBα and p-p65/p65 expression was reduced. When NaAsO2 and TAK-242 were combined, apoptosis and inflammation were attenuated. Besides MyD88, p-IκBα/IκBα and p-p65/p65 expression was reduced compared to the NaAsO2 group. We found that NaAsO2 induce apoptosis and inflammation in BLR-3A cells, which may be related to inhibit SOCS1 through regulation of DNMT1 and thus activating the TLR4/MyD88/NF-κB signaling pathway.

Astaxanthin from microalgae: A review on structure, biosynthesis, production strategies and application

Astaxanthin is a red-colored secondary metabolite with excellent antioxidant properties, typically finds application as foods, feed, cosmetics, nutraceuticals, and medications. Astaxanthin is usually produced synthetically using chemicals and costs less as compared to the natural astaxanthin obtained from fish, shrimps, and microorganisms. Over the decades, astaxanthin has been naturally synthesized from Haematococcus pluvialis in commercial scales and remains exceptional, attributed to its higher bioactive properties as compared to synthetic astaxanthin. However, the production cost of algal astaxanthin is still high due to several bottlenecks prevailing in the upstream and downstream processes. To that end, the present study intends to review the recent trends and advancements in astaxanthin production from microalgae. The structure of astaxanthin, sources, production strategies of microalgal astaxanthin, and factors influencing the synthesis of microalgal astaxanthin were discussed while detailing the pathway involved in astaxanthin biosynthesis. The study also discusses the relevant downstream process used in commercial scales and details the applications of astaxanthin in various health related issues.

The Protective Effects of Astaxanthin (AST) in the Liver of Weaned Piglets

During the weaning period, piglets are exposed to high levels of stress, which often causes problems with the digestive system. This stress also promotes the production of free radicals, resulting in oxidative stress. Astaxanthin (AST) stands out as one of the most potent antioxidants. Its resistance to light and heat makes it particularly valuable in compound feed production. This study was to determine the effect of AST impact on liver histology and gene expression in piglets. For our experiment, we used 16 weaned piglets of the PL breed, which we divided into two groups: Group I (control group with no AST supplementation) and Group II (supplemented with AST at 0.025 g/kg). Both feed mixtures were iso-proteins and iso-energetic, meeting the nutritional requirements of the piglets. The experiment lasted from day 35 to day 70 of the piglets' age, during which they had ad libitum access. The results indicate that the addition of AST prevents liver fibrosis due to reduced collagen deposition in the tissue. Analysis of gene expression supported these results. In the AST-supplemented group, we noted a decrease in NR1H3 expression, an increase in CYP7A1 expression, and reductions in the expression of NOTCH1 and CREB genes.

Ameliorative Effects of Luteolin and Activated Charcoal on Growth Performance, Immunity Function, and Antioxidant Capacity in Broiler Chickens Exposed to Deoxynivalenol

Deoxynivalenol (DON, Vomitoxin) is a threatening mycotoxin that mainly produces oxidative stress and leads to hepatotoxicity in poultry. Antioxidant dietary supplements dramatically boost immunity, safeguarding animals from DON poisoning. Luteolin (LUT) is an active plant-derived compound that poses influential antioxidants. This study explored the effectiveness of LUT in combination with activated charcoal (AC) in detoxifying DON in broilers. The 180 one-day broiler chickens were allocated into five different groups having six replicates in each group, provided with ad libitum feed during the trial period (28 days) as follows: in the control group, basal diet (feed with no supplementation of LUT, AC or DON); in group 2, a basal diet added with 10 mg/kg DON from contaminated culture (DON); in group 3, a basal diet augmented by 350 mg/kg LUT and DON 10 mg/kg (DON + LUT); in group 4, a basal diet supplemented by DON 10 mg/kg + AC 200 mg/kg (DON + AC); and in group 5, a basal diet supplemented by 10 mg/kg DON + 350 mg/kg LUT + 200 mg/kg AC (DON + LUT + AC). Concerning the control group, the DON-treated broilers demonstrated a significant decrease in growth performance (p < 0.05) and serum immunoglobulin (p < 0.05) contents, negatively changing the serum biochemical contents and enzymatic activities and an increase in histopathological liver lesions. Furthermore, DON substantially increased (p < 0.05) malondialdehyde (MDA) concentration and decreased total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) levels in the serum and liver. The intake of AC and LUT to the DON-contaminated diet decreased DON residue in the liver and potentially reduced the adverse effects of DON. Considering the results, supplementation of LUT with mycotoxin adsorbent has protective effects against mycotoxicosis caused by DON. It could be helpful for the development of novel treatments to combat liver diseases in poultry birds. Our findings may provide important information for applying LUT and AC in poultry production.

Ganoderma lucidum polysaccharides improve lipid metabolism against high-fat diet-induced dyslipidemia

ETHNOPHARMACOLOGICAL RELEVANCE

As a kind of traditional medicinal fungi, Ganoderma lucidum has been employed as folk medicine in China against multiple metabolic diseases on account of its superior bioactivities. Recently, accumulated reports have investigated the protective effects of G. lucidum polysaccharides (GLP) on ameliorating dyslipidemia. However, the specific mechanism by which GLP improves dyslipidemia is not completely clear.

AIMS OF THE STUDY

This study aimed to investigate the protective effects of GLP on high-fatdiet-induced hyperlipidemia and exploring its underlying mechanism.

MATERIALS AND METHODS

The GLP was successfully obtained from G. lucidum mycelium. The mice were conducted with high-fatdiet to establish the hyperlipidemia model. Biochemical determination, histological analysis, immunofluorescence, western blot and real-time qPCR were used to assess the alterations in high-fatdiet-treated mice after the GLP intervention.

RESULTS

It was found that GLP administration significantly decreased body weight gain and the excessive lipid levels, and partly alleviated tissue injury. Oxidative stress and inflammations were efficiently ameliorated after the treatment of GLP by activing Nrf2-Keap1 and inhibiting NF-κB signal pathways. GLP promoted cholesterol reverse transport by LXRα-ABCA1/ABCG1 signaling, increased the expressions of CYP7A1 and CYP27A1 responsible for bile acids production, accompanied by inhibition of intestinal FXR-FGF15 levels. Besides, multiple target proteins involved in lipid metabolism were also significantly modulated under the intervention of GLP.

CONCLUSION

Taken together, our results suggested that GLP showed potential lipid-lowering effects and its possible mechanism was involved in improving oxidative stress and inflammation response, modulating bile acids synthesis and lipid regulatory factors, and promoting reverse cholesterol transport, thereby suggesting that GLP may possibly used as a dietary supplement or medication for the adjuvant therapy for hyperlipidemia.

From animal to cell model: Pyroptosis targeted-fibrosis is a novel mechanism of lead-induced testicular toxicity

Lead (Pb) exists widely in soil and seriously threatens agricultural soil and food crops. Pb can cause serious damage to organs. In this study, the animal model of Pb-induced rat testicular injury and the cell model of Pb-induced TM4 Sertoli cell injury were established to verify whether the testicular toxicity of Pb was related to pyroptosis-mediated fibrosis. The results of experiment in vivo showed that Pb could cause oxidative stress and up-regulated the expression levels of inflammation, pyroptosis, and fibrosis-related proteins in the testis of rats. The results of experiments in vitro showed that Pb induced the cell damage, enhanced the reactive oxygen species level in the TM4 Sertoli cells. After using nuclear factor-kappa B inhibitors and Caspase-1 inhibitors, the elevation of TM4 Sertoli cell inflammation, pyroptosis, and fibrosis-related proteins induced by Pb exposure was significantly decreased. Taken together, Pb can cause pyroptosis-targeted fibrosis and ultimately issues in testicular damage.

The role of mitochondrial dynamics imbalance in hexavalent chromium-induced apoptosis and autophagy in rat testis

Hexavalent chromium (Cr(VI)) is a ubiquitous environmental pollutant that can cause reproductive toxicity. However, the exact mechanism of Cr(VI)-induced testis toxicity remains largely elusive. This study aims to explore the possible molecular mechanism of Cr(VI)-provoked testicular toxicity. Male Wistar rats were intraperitoneally injected with 0, 2, 4, or 6 mg/kg body weight/day of potassium dichromate (K₂Cr₂O₇), respectively, for 5 weeks. The results revealed that Cr(VI)-treated rat testis presented varying degrees of damage in a dose-dependent manner. Concretely, Cr(VI) administration suppressed Sirtuin 1/Peroxisome proliferator-activated receptor-γ coactivator-1α pathway and led to mitochondrial dynamics disorder, along with the elevation of mitochondrial division and the repression of mitochondrial fusion. Meanwhile, the downstream effector of Sirt1, nuclear factor-erythroid-2-related factor 2 (Nrf2), was downregulated, and correspondingly exacerbated oxidative stress. Mitochondrial dynamics disorder and Nrf2 inhibition collectively contribute to abnormal mitochondrial dynamics in testis, which further promotes apoptosis and autophagy, evidenced by dose-dependently increasing the protein levels and gene expressions of apoptosis-related (including Bcl-2-associated X protein, cytochrome c, and cleaved-caspase 3) and autophagy-related (Beclin-1, ATG4B, and ATG5). Collectively, our results demonstrate that Cr(VI) exposure induced testis apoptosis and autophagy by disrupting the balance of mitochondrial dynamics and the oxidation-reduction process in rats.

Toxicity prediction: An application of alternative testing and computational toxicology in contaminated groundwater sites in Taiwan

Groundwater contamination remains a global threat due to its toxic effects to humans and the environment. The remediation of contaminated groundwater sites can be costly, thus, identifying the priority areas of concern is important to reduce money spent on resources. In this study, we aimed to identify and rank the priority groundwater sites in a contaminated petrochemical district by combining alternative, non-animal approaches - chemical analysis, cell-based high throughput screening (HTS), and Toxicological Priority Index (ToxPi) computational toxicology tool. Groundwater samples collected from ten different sites in a contaminated district showed pollutant levels below the detection limit, however, hepatotoxic bioactivity was demonstrated in human hepatoma HepaRG cells. Integrating the pollutants information (i.e., pollutant characteristics and concentration data) with the bioactivity data of the groundwater samples, an evidence-based ranking of the groundwater sites for future remediation was established using ToxPi analysis. The currently presented combinatorial approach of screening groundwater sites for remediation purposes can further be refined by including relevant parameters, which can boost the utility of this approach for groundwater screening and future remediation.

A biochemical and histology experimental approach to investigate the adverse effect of chronic lead acetate and dietary furan on rat lungs

Despite lead widespread environmental pollution, its effect on humans and livestock's respiratory systems remains inadequately investigated. Similarly, furan is industrially relevant with enormous environmental presence. Lead and furan can be ingested -via lead pipes contaminated water and heat-treated food respectively. Thus, humans are inadvertently exposed continuously. Lead toxicity is well studied, and furan have earned a position on the IARC's list of carcinogens. Here, we evaluate the effect of co-exposure to lead and furan on rat lungs. Thirty Wistar rats were grouped randomly into six cohorts (n = 6) consisting of a control group, furan alone group, lead acetate (PbAc) alone group and three other groups co-exposure to graded PbAc (1, 10 & 100 µg/L) alongside a constant furan (8 mg/kg) dose. After twenty-eight days, enzymatic and non-enzymatic antioxidant, oxidative stress and inflammatory biomarkers were biochemically evaluated. The ELISA-based technique was used to measure oxidative-DNA damage (8-OHG), tumour protein 53 (TP53) expressed and tumour necrotic factor-alpha (TNF-α) level. Dose-dependent increases (p < 0.05) in reactive oxygen and nitrogen species, malondialdehyde, nitric oxide, myeloperoxidase, TNF-α and TP53 level, with an associated decrease (p < 0.05) in enzymatic and non-enzymatic antioxidants were observed in the furan, PbAc and the co-treated rats relative to the control. In addition, PbAc and furan treatment impaired the histoarchitectural structures of rat lungs, exemplified by pro-inflammatory cell infiltration and trafficking into the bronchioles and alveolar spaces. Co-exposure to furan and PbAc may contribute to lung dysfunction via loss of redox balance, genomic damage/instability, inflammation and disrupted histoarchitectural features.

Effects of thiacloprid exposure on microbiota-gut-liver axis: Multiomics mechanistic analysis in Japanese quails

Neonicotinoid insecticides (NNIs) are the most widely used class of pesticides globally. However, NNIs may cause adverse health effects, including chronic liver disease, and perturbation of the gut microbiota. Thiacloprid (THI) is one of the NNIs widely used in agriculture. Therefore, it is essential to elucidate effects of THI on the microbiota-gut-liver axis to assess the risk of chronic liver disease following exposure to NNIs. This study aimed at investigating whether THI exposure promoted liver injury by altering the gut microbiota and related metabolites. In this study, healthy male quails were exposed to 2 or 4 mg/kg THI or 0.75 % (w/v) saline once daily for 6 weeks, respectively. Metabolomics, 16S rRNA sequencing, and transcriptomic methods were performed to analyze the toxic mechanisms of THI in Japanese quails. We found that THI evoked damage and disruption to intestinal barrier function, leading to increased harmful substances such as lipopolysaccharide (LPS) and phenylacetic acid entering the liver. Besides, our results showed significantly altered hepatic bile acid and cholesterol metabolism in THI-exposed quails, with abnormal liver lipid metabolism, showing severe liver injury, fibrosis, and steatosis compared with the control quails. In conclusion, THI exposure aggravates liver injury via microbiota-gut-liver axis.

Luteolin alleviates inorganic mercury-induced liver injury in quails by resisting oxidative stress and promoting mercury ion excretion

BackgroundInorganic mercury is a well-known toxic substance that can cause oxidative stress and liver damage. Luteolin (Lut) is a kind of natural antioxidant, which is widely found in plants. Therefore, we focused on exploring the alleviative effect of Lut on liver injury induced by mercuric chloride (HgCl₂), and the potential molecular mechanism of eliminating mercury ions in quails.Methods and resultsTwenty-one-day-old male quails were randomly split into four groups: control group, Lut group, HgCl₂ group, and HgCl₂ + Lut group. The test period was 12 weeks. The results showed that Lut could significantly ameliorate oxidative stress, the release of inflammatory factors, and liver damage caused by HgCl_2, and reduce the accumulation of Hg²⁺ in quail liver. Furthermore, Lut evidently increased the levels of protein kinase C α (PKCα), nuclear factor-erythroid-2-related factor 2 (Nrf2), and its downstream proteins, and inhibited nuclear factor-kappaB (NF-κB) production in the liver of quails treated by HgCl₂.ConclusionsTo sum up, our results suggest that Lut not only reduces the levels of oxidative stress and inflammation, but also promotes the excretion of Hg²⁺ by promoting the PKCα/Nrf2 signaling pathway to alleviate HgCl₂-induced liver injury in quails.

PINK1/Parkin-Mediated Mitophagy Partially Protects against Inorganic Arsenic-Induced Hepatic Macrophage Polarization in Acute Arsenic-Exposed Mice

Inorganic arsenic is a well-known environmental toxicant and carcinogen, and there is overwhelming evidence for an association between this metalloid poisoning and hepatic diseases. However, the biological mechanism involved is not well characterized. In the present study, we probed how inorganic arsenic modulates the hepatic polarization of macrophages, as well as roles of PTEN-induced kinase 1 (PINK1)/Parkin-mediated mitophagy participates in regulating the metalloid-mediated macrophage polarization. Our results indicate that acute arsenic exposure induced macrophage polarization with up-regulated gene expression of inducible nitric oxide synthase (Inos) and arginase-1 (Arg1), monocyte chemotactic protein-1 (Mcp-1) and macrophage inflammatory protein-2 (Mip-2), tumor necrosis factor (Tnf)-α, interleukin (Il)-1β and Il-6, as well as anti-inflammatory factors Il-4 and Il-10. In parallel, we demonstrated the disrupted hepatic redox balance typically characterized by the up-regulation of hydrogen peroxide (H₂O₂) and glutathione (GSH), and activation of PINK1/Parkin-mediated mitophagy in the livers of acute arsenic-exposed mice. In addition, our results demonstrate that it might be the PINK1/Parkin-mediated mitophagy that renders hepatic macrophage refractory to arsenic-induced up-regulation of the genes Inos, Mcp-1, Mip-2, Tnf-α, Il-1β, Il-6 and Il-4. In this regard, this is the first time the protective effects of PINK1/Parkin-mediated mitophagy in inorganic arsenic-induced hepatic macrophage polarization in vivo have been reported. These findings add novel insights into the arsenical immunotoxicity and provide a basis for the preve.ntive and therapeutic potential of PINK1/Parkin-mediated mitophagy in arsenic poisoning.

Inhibition of the Nrf2 signaling pathway involved in imidacloprid-induced liver fibrosis in Coturnix japonica

Imidacloprid (IMI) is a kind of widely used neonicotinoid insecticide. However, the toxicity of IMI is not only applied to target pests but also causes serious negative effects on birds and other creatures. Our previous studies have shown that long-term exposure to IMI can induce liver fibrosis in quails. However, the specific mechanism of quail liver fibrosis induced by IMI is not completely clear. Accordingly, the purpose of this study is to further clarify the potential molecular mechanism of IMI-induced liver fibrosis in quails. Japanese quails (Coturnix japonica) were treated with/without IMI (intragastric administration with 6 mg/kg body weight) in the presence/absence of luteolin (Lut) (fed with 800 mg/kg) for 90 days. The results reveal that IMI can induce hepatic fibrosis, oxidative stress, fatty degeneration, inflammation, and the down-expression of nuclear factor-E2-related factor-2 (Nrf2). Furthermore, the treatment of Lut, a kind of Nrf2 activator, increased the expression of Nrf2 in livers and alleviated liver fibrosis in quails. Altogether, our study demonstrates that inhibition of the Nrf2 pathway is the key to liver fibrosis induced by IMI in quails. These results provide a new understanding for the study of the toxicity of IMI and a practical basis for the treatment of liver fibrosis caused by IMI.

The heart as a target for deltamethrin toxicity: Inhibition of Nrf2/HO-1 pathway induces oxidative stress and results in inflammation and apoptosis

As a synthetic pyrethroid pesticide, deltamethrin (DLM) is widely employed in veterinary medicine and farming, and DLM-triggered oxidative stress largely causes serious harm to the organism. It is well-known that nuclear factor erythroid-2-related factor 2/heme oxygenase-1 (Nrf2/HO-1), a pivotal endogenous anti-oxidative pathway, acts on inhibiting oxidative stress-induced cell injury under the activated state. The purpose of this research was to observe the impact and molecular mechanism of DLM on inflammation and apoptosis in quail cardiomyocytes based on the Nrf2/HO-1 signaling route. In this research, quails were established as a cardiac injury model through gastric infusion of various doses of DLM (0, 15, 30, and 45 mg/kg b. w.) for 12 weeks. Our results showed that DLM could induced cardiomyocyte injury in a dose-dependent manner though weakening antioxidant defense via down-regulating Nrf2 and its downstream protein HO-1. Furthermore, DLM stimulation induced apoptosis in quail heart by decreasing the protein expressions of B-cell lymphoma-extra large and B-cell lymphoma gene 2 (Bcl-2), as well as increasing P53, caspase 3, and Bcl-2-associated X protein levels. Meanwhile, relative levels of nuclear factor-kappa B and interleukin-1β in quail hearts were up-regulated under DLM intervention progressively. Collectively, our study demonstrates that chronic exposure to DLM can induce quail cardiomyocyte inflammation and apoptosis by mediating Nrf2/HO-1 signaling pathway-related oxidative stress.

Deltamethrin induces apoptosis in cerebrum neurons of quail via promoting endoplasmic reticulum stress and mitochondrial dysfunction

Deltamethrin (DLM) is a widely used and highly effective insecticide. DLM exposure is harmful to animal and human. Quail, as a bird model, has been widely used in the field of toxicology. However, there is little information available in the literature about quail cerebrum damage caused by DLM. Here, we investigated the effect of DLM on quail cerebrum neurons. Four groups of healthy quails were assigned (10 quails in each group), respectively given 0, 15, 30, and 45 mg/kg DLM by gavage for 12 weeks. Through the measurements of quail cerebrum, it was found that DLM exposure induced obvious histological changes, oxidative stress, and neurons apoptosis. To further explore the possible molecular mechanisms, we performed real-time quantitative PCR to detect the expression of endoplasmic reticulum (ER) stress-related mRNA such as glucose regulated protein 78 kD, activating transcription factor 6, inositol requiring enzyme, and protein kinase RNA (PKR)-like ER kinase. In addition, we detected ATP content in quail cerebrum to evaluate the functional status of mitochondria. The study showed that DLM exposure significantly increased the expression of ER stress-related mRNA and decreased ATP content in quail cerebrum tissues. These results suggest that chronic exposure to DLM induces apoptosis of quail cerebrum neurons via promoting ER stress and mitochondrial dysfunction. Furthermore, our results provide a novel explanation for DLM-induced apoptosis of avian cerebrum neurons.

The Putative Role of Astaxanthin in Neuroinflammation Modulation: Mechanisms and Therapeutic Potential

Neuroinflammation is a protective mechanism against insults from exogenous pathogens and endogenous cellular debris and is essential for reestablishing homeostasis in the brain. However, excessive prolonged neuroinflammation inevitably leads to lesions and disease. The use of natural compounds targeting pathways involved in neuroinflammation remains a promising strategy for treating different neurological and neurodegenerative diseases. Astaxanthin, a natural xanthophyll carotenoid, is a well known antioxidant. Mounting evidence has revealed that astaxanthin is neuroprotective and has therapeutic potential by inhibiting neuroinflammation, however, its functional roles and underlying mechanisms in modulating neuroinflammation have not been systematically summarized. Hence, this review summarizes recent progress in this field and provides an update on the medical value of astaxanthin. Astaxanthin modulates neuroinflammation by alleviating oxidative stress, reducing the production of neuroinflammatory factors, inhibiting peripheral inflammation and maintaining the integrity of the blood-brain barrier. Mechanistically, astaxanthin scavenges radicals, triggers the Nrf2-induced activation of the antioxidant system, and suppresses the activation of the NF-κB and mitogen-activated protein kinase pathways. With its good biosafety and high bioavailability, astaxanthin has strong potential for modulating neuroinflammation, although some outstanding issues still require further investigation.

Poria cocos water-soluble polysaccharide modulates anxiety-like behavior induced by sleep deprivation by regulating the gut dysbiosis, metabolic disorders and TNF-α/NF-κB signaling pathway

Poria cocos (P. cocos) has been traditionally used as folk medicine and functional food in China for more than 2000 years. The water-soluble polysaccharide is the main component of P. cocos decoction. The effects and mechanisms of the water-soluble polysaccharide from P. cocos (PCWP) were investigated in chronic sleep deprivation (CSD)-induced anxiety in rats. CSD induced anxiety, gut dysbiosis, and inflammatory responses, and reduced neurotransmitter levels, whereas PCWP intervention ameliorated anxiety-like behaviors, increased the levels of 5-hydroxytryptamine, dopamine, norepinephrine, and γ-aminobutyric acid in the hypothalamus, regulated gastrointestinal peptide levels, reduced inflammatory factors, and inhibited the tumor necrosis factor (TNF)-α/nuclear factor (NF)-κB signaling pathway in rats with CSD. The changes in the intestinal flora composition were determined using 16S rDNA sequencing, and indicated that PCWP significantly improved species richness and diversity in the intestinal flora of rats with anxiety, and adjusted the abundance of the following dysregulated bacteria closer to that of the normal group: Rikenellaceae_RC9_gut_group, Ruminococcus, Prevotellaceae_UCG-001, Prevotellaceae_NK3B31_group, Fusicatenibacter. Metabolomics was used to analyze fecal samples to identify significantly altered metabolites in the PCWP-treated groups. Thirty-eight PCWP-related metabolites and four metabolic pathways such as sphingolipid metabolism, taurine and hypotaurine metabolism, vitamin B6 metabolism, and glycerophospholipid metabolism were explored. The results of serum metabolomics showed that 26 biomarkers were significantly changed after PCWP intervention compared with the model group. The regulatory effects of metabolic pathway enrichment on sphingolipid, phenylalanine, and taurine and hypotaurine metabolism, and validation results showed that PCWP intervention regulated the activity of enzymes involved in the above metabolic pathways. A strong correlation between intestinal bacteria and potential biomarkers was found. Our findings present new evidence supporting the potential effect of PCWP in preventing the progression of anxiety by inhibiting the TNF-α/NF-κB signaling pathway, alleviating metabolic disorders, and ameliorating the gut microflora imbalance.

Health benefits of astaxanthin against age-related diseases of multiple organs: A comprehensive review

Age-related diseases are associated with increased morbidity in the past few decades and the cost associated with the treatment of these age-related diseases exerts a substantial impact on social and health care expenditure. Anti-aging strategies aim to mitigate, delay and reverse aging-associated diseases, thereby improving quality of life and reducing the burden of age-related pathologies. The natural dietary antioxidant supplementation offers substantial pharmacological and therapeutic effects against various disease conditions. Astaxanthin is one such natural carotenoid with superior antioxidant activity than other carotenoids, as well as well as vitamins C and E, and additionally, it is known to exhibit a plethora of pharmacological effects. The present review summarizes the protective molecular mechanisms of actions of astaxanthin on age-related diseases of multiple organs such as Neurodegenerative diseases [Alzheimer's disease (AD), Parkinson's disease (PD), Stroke, Multiple Sclerosis (MS), Amyotrophic lateral sclerosis (ALS), and Status Epilepticus (SE)], Bone Related Diseases [Osteoarthritis (OA) and Osteoporosis], Cancers [Colon cancer, Prostate cancer, Breast cancer, and Lung Cancer], Cardiovascular disorders [Hypertension, Atherosclerosis and Myocardial infarction (MI)], Diabetes associated complications [Diabetic nephropathy (DN), Diabetic neuropathy, and Diabetic retinopathy (DR)], Eye disorders [Age related macular degeneration (AMD), Dry eye disease (DED), Cataract and Uveitis], Gastric Disorders [Gastritis, Colitis, and Functional dyspepsia], Kidney Disorders [Nephrolithiasis, Renal fibrosis, Renal Ischemia reperfusion (RIR), Acute kidney injury (AKI), and hyperuricemia], Liver Diseases [Nonalcoholic fatty liver disease (NAFLD), Alcoholic Liver Disease (AFLD), Liver fibrosis, and Hepatic Ischemia-Reperfusion (IR) Injury], Pulmonary Disorders [Pulmonary Fibrosis, Acute Lung injury (ALI), and Chronic obstructive pulmonary disease (COPD)], Muscle disorders (skeletal muscle atrophy), Skin diseases [Atopic dermatitis (ATD), Skin Photoaging, and Wound healing]. We have also briefly discussed astaxanthin's protective effects on reproductive health.

Mycelium polysaccharides of Macrolepiota procera alleviate reproductive impairments induced by nonylphenol

Nonylphenol (NP) exposure has become a crucial inducement of male reproductive disorders in the world. Therefore, it is urgent to seek solutions to alleviate the toxicity of NP. This study was oriented toward studying the protective effects of Macrolepiota procera mycelium polysaccharides (MMP) on NP-induced reproductive impairments. After NP administration, declined sperm amounts and testis index, increased the deformity rate of sperms, aberrant hormone secretion and testicular pathological injury were observed, corporately leading to reproductive capacity attenuation. Importantly, MMP significantly reversed the foregoing changes in NP-treated mice. Notably, it has been observed that the MMP therapy remarkably improved oxidative stress, apoptosis, autophagy and inflammatory responses, and suppressed the Akt/mTOR signaling pathway in testicular tissues. These results manifested that MMP might be a promising treatment strategy for ameliorating the biotoxicity of NP.

Ganoderic acid A from Ganoderma lucidum protects against alcoholic liver injury through ameliorating the lipid metabolism and modulating the intestinal microbial composition

Alcoholic liver injury is mainly caused by long-term excessive alcohol consumption and has become a global public threat to human health. It is well known that Ganoderma lucidum has excellent beneficial effects on liver function and lipid metabolism. The object of this study was to investigate the hepatoprotective effects of ganoderic acid A (GAA, one of the main triterpenoids in G. lucidum) against alcohol-induced liver injury and reveal the underlying mechanisms of its protective effects. The results showed that oral administration of GAA significantly inhibited the abnormal elevation of the liver index, serum total triglyceride (TG), cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mice exposed to alcohol intake, and also significantly protected the liver against alcohol-induced excessive lipid accumulation and pathological changes. Besides, alcohol-induced oxidative stress in the liver was significantly ameliorated by the dietary intervention of GAA through decreasing the hepatic levels of lactate dehydrogenase (LDH) and malondialdehyde (MDA), and increasing hepatic activities of catalase (CAT), superoxide dismutase (SOD), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and hepatic levels of glutathione (GSH). In addition, GAA intervention evidently ameliorated intestinal microbial disorder by markedly increasing the abundance of Muribaculaceae, Prevotellaceae, Jeotgalicoccus, Bilophila, Family_XIII_UCG_001, Aerococcus, Ruminococcaceae_UCG_005, Harryflintia, Christensenellaceae, Rumonpcpccaceae, Prevotelaceae_UCG_001, Clostridiales_vadinBB60_group, Parasutterella and Bifidobacterium, but decreasing the proportion of Lactobacillus, Burkholderia_Caballeroria_Paraburkholderia, Escherichia_Shigella and Erysipelatoclostridium. Furthermore, liver metabolomics based on UPLC-QTOF/MS demonstrated that oral administration of GAA had a significant regulatory effect on the composition of liver metabolites in mice exposed to alcohol intake, especially the levels of the biomarkers involved in the metabolic pathways of riboflavin metabolism, glycine, serine and threonine metabolism, pyruvate metabolism, glycolysis/gluconeogenesis, biosynthesis of unsaturated fatty acids, synthesis and degradation of ketone bodies, fructose and mannose metabolism. Moreover, dietary supplementation of GAA significantly regulated the hepatic mRNA levels of lipid metabolism and inflammatory response related genes. Conclusively, these findings demonstrate that GAA has beneficial effects on alleviating alcohol-induced liver injury and is expected to become a new functional food ingredient for the prevention of alcoholic liver injury.

Protective role of Siberian onions against toxin-induced liver dysfunction: an insight into health-promoting effects

Siberian onions (SOs) are delicious wild vegetables. Their taste is most unique, not only like scallions but also like leeks or garlic. They also have a traditional medicinal value for anti-inflammation, anti-oxidation, and anti-pyretic analgesia, particularly facilitating hepatoprotective effects. The current study investigates the potential mechanism of SOs against toxin-induced liver dysfunction. BALB/c mice were administrated with SO or silymarin by oral gavage for one week, followed by injecting carbon tetrachloride (CCl₄) to induce hepatic fibrosis. The effect of SO against hepatic fibrosis was evaluated by examining the liver tissue for serum transaminase, oxidative stress, extracellular matrix, histological alterations, cytokine levels, and apoptosis. In vitro, HSC-T6 cells were cultured with the supernatant from Raw 264.7 cells stimulated with lipopolysaccharides, followed by SO extracts or Niclosamide (Signal Transducer and Activator of Transcription 3 (STAT3) inhibitor) at indicated time periods and doses. SO decreased serum transaminase levels and oxidative stress, and regulated the balance of ECM in CCl₄-induced mice, including α-SMA, collagen-I and TIMP-1. SO reduced the release of inflammatory factors and regulated apoptosis-associated proteins, which is related to the inhibition of STAT3 phosphorylation. Moreover, SO reduced the positive expressions of α-SMA and NLRP3 by inhibiting STAT3 phosphorylation in activated HSCs. SO could show health-promoting effects for liver dysfunction by alleviating hepatic fibrogenesis, apoptosis and inflammation in the development of hepatic fibrosis potential depending on the STAT3 signaling pathway.

Hesperidin protects against cisplatin-induced cardiotoxicity in mice by regulating the p62-Keap1-Nrf2 pathway

Hesperidin (HES) is an abundant and economical dietary bioflavonoid, and it has several pharmacological properties such as antioxidant activity and powerful cardiac protection. However, HES protection against cisplatin (CP)-induced cardiotoxicity and its mechanism have not been fully clarified. The current study was performed to further elucidate the mechanism of HES against CP-induced cardiotoxicity. Mice were orally administered HES (100 or 300 mg kg^-1 day^-1) for 7 consecutive days and then injected intraperitoneally (i.p.) with CP (5 mg kg^-1) on days 3 and 6. On day 8, mice were anaesthetised with sodium pentobarbital (50 mg kg^-1, i.p.), and blood and heart samples were collected for analysis. HES treatment reduced CP-induced cardiac pathologic damage and leakage of the myocardial markers cardiac troponin I (cTnI), creatine kinase (CK), and lactate dehydrogenase (LDH). HES treatment reduced levels of reactive oxygen species (ROS) and malondialdehyde (MDA), which is an oxidative product, and increased antioxidant marker levels including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). HES also reduced the CP-induced release of the inflammatory factors tumour necrosis factor (TNF)-α and interleukin (IL)-6. Additionally, HES treatment up-regulated the expression of anti-apoptotic protein Bcl-2 and down-regulated the expression of pro-apoptotic proteins Bax and Caspase-3. HES treatment also improved the expression of pathway proteins p62 and Nrf2 and inhibited the increase in CP-induced Keap1 expression. Thus, HES may provide protection against CP cardiotoxicity through inhibiting oxidative stress, inflammation, and apoptosis, which may contribute to activation of the p62-Keap1-Nrf2 signalling pathway. These findings suggest that HES may be a promising protective agent against CP cardiotoxicity in future anticancer clinical practice.

Harmful Effects of Inorganic Mercury Exposure on Kidney Cells: Mitochondrial Dynamics Disorder and Excessive Oxidative Stress

Mercury is widely used in industry and has caused global environmental pollution. Inorganic mercury accumulates in the body causes damage to many organs, and the kidney is the most susceptible to the toxic effects of mercury. However, the underlying specific molecular mechanism of renal injury induced by inorganic mercury remains unclear at the cellular level. Therefore, in order to understand its molecular mechanism, we used in vitro method. We established experimental models by treating human embryonic kidney epithelial cell line (HEK-293 T) cells with HgCl₂ (0, 1.25, 5, and 20 µmol/L). We found that HgCl₂ can lead to a decrease in cell viability and oxidative stress of HEK-293 T, which may be mediated by upregulation mitochondrial fission. In addition, HgCl₂ exposure resulted in the mitochondrial disorder of HEK-293 T cells, which was mediated by downregulating the expression of silent information regulator two ortholog 1 (Sirt1)/peroxisome proliferator-activated receptor coactivator-1α (PGC-1α) signaling pathway. In summary, our results suggest that HgCl₂ induces HEK-293 T cell toxicity through promoting Sirt1/PGC-1α axis-mediated mitochondrial dynamics disorder and oxidative stress. Sirt1/PGC-1α may be an appealing pharmaceutical target curing HgCl₂-induced kidney injury.

Activation of the GPX4/TLR4 Signaling Pathway Participates in the Alleviation of Selenium Yeast on Deltamethrin-Provoked Cerebrum Injury in Quails

Deltamethrin (DLM) is a member of pyrethroid pesticide widely applied for agriculture and aquaculture, and its residue in the environment seriously threatens the bio-safety. The cerebrum might be vulnerable to pesticide-triggered oxidative stress. However, there is no specific antidote for treating DLM-triggered cerebral injury. Selenium (Se) is an essential trace element functionally forming selenoprotein glutathione peroxidase (GPX) in antioxidant defense. Se yeast (SY) is a common and effective organic form of Se supplement with high selenomethionine content. Accordingly, this study focused on investigating the therapeutic potential of SY on DLM-induced cerebral injury in quails after chronically exposing to DLM and exploring the underlying mechanisms. Quails were treated with/without SY (0.4 mg kg^-1 SY added in standard diet) in the presence/absence of DLM (45 mg kg^-1 body weight intragastrically) for 12 weeks. The results showed SY supplementation ameliorated DLM-induced cerebral toxicity. Concretely, SY elevated the content of Se and increased GPX4 level in DLM-treated quail cerebrum. Furthermore, SY enhanced antioxidant defense system by upregulating nuclear factor-erythroid-2-related factor 2 (Nrf2) associated members. Inversely, SY diminished the changes of apoptosis- and inflammation-associated proteins and genes including toll-like receptor 4 (TLR4). Collectively, our results suggest that dietary SY protects against DLM-induced cerebral toxicity in quails via positively regulating the GPX4/TLR4 signaling pathway. GPX4 may be a potential therapeutic target for insecticide-induced biotoxicity.

Upregulation of Nrf2 signaling and suppression of ferroptosis and NF-κB pathway by leonurine attenuate iron overload-induced hepatotoxicity

Hepatotoxicity is a major health concern that associates the iron overload diseases including hemochromatosis, sickle cell anemia, and thalassemia. Induction of ferroptosis, oxidative stress, and inflammation substantially mediates the iron-evoked hepatotoxicity. The current work investigated the potential protective effect of the natural alkaloid leonurine against the iron-induced hepatotoxicity and elucidated the underlining molecular mechanisms. Male Wistar rats were treated with iron only (30 mg/kg every other day over a ten-day period via intraperitoneal injection) or with iron and leonurine (leonurine: 100 mg/kg/day per oral via gastric gavage for 10 days) to establish the iron-overload model. Liver and blood specimens were then collected and subjected to molecular, biochemical, and histopathological investigations. The results revealed the ability of leonuirne to suppress the iron-induced ferroptosis as reflected by modulation of the ferroptotic biomarkers glutathione peroxidase 4, cyclooxygenase-2, liver iron content, lipid hydroperoxides, and the leakage of the liver intracellular enzymes. Leonurine alleviated the iron-induced oxidative damage and inflammatory response in the liver tissues as indicated by decreased levels of DNA oxidation, lipid peroxidation, and the pro-inflammatory cytokines. In the same context, it improved the antioxidant potential of the liver tissues and ameliorated the iorn-induced histopathological abnormalities. Mechanistically, leonurine enhanced nuclear translocation of the antioxidant transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) and increased protein levels of its downstream targets NAD(P)H-quinone oxidoreductase 1 and heme oxygenase-1. Additionally, it suppressed the nuclear translocation of the inflammatory transcription factor nuclear factor kappa B (NF-κB) and downregulated its downstream pro-inflammatory cytokines tumor necrosis factor-alpha and interleukin-1 beta. The study highlights the hepatoprotective activity of leonurine against the iron-evoked hepatotoxicity that is potentially mediated through modulation of Nrf2 and NF-κB signaling.

Tanshinone I Mitigates Steroid-Induced Osteonecrosis of the Femoral Head and Activates the Nrf2 Signaling Pathway in Rats

Steroid-induced osteonecrosis of the femoral head (SIONFH) is a frequent orthopedic disease caused by long-term or high-dose administration of corticosteroids. Tanshinone I (TsI), a flavonoid compound isolated from Salvia miltiorrhiza Bunge, has been reported to inhibit osteoclastic differentiation in vitro. This study aimed to investigate whether TsI can ameliorate SIONFH. Herein, SIONFH was induced by intraperitoneal injection of 20 μg/kg lipopolysaccharide every 24 h for 2 days, followed by an intramuscular injection of 40 mg/kg methylprednisolone every 24 h for 3 days. Four weeks after the final injection of methylprednisolone, the rats were intraperitoneally administrated with low-dose (5 mg/kg) and high-dose (10 mg/kg) TsI once daily for 4 weeks. Results showed that TsI significantly alleviated osteonecrotic lesions of the femoral heads as determined by micro-CT analysis. Furthermore, TsI increased alkaline phosphatase activity and expressions of osteoblastic markers including osteocalcin, type I collagen, osteopontin, and Runt-related transcription factor 2 and decreased tartrate-resistant acid phosphatase activity and expressions of osteoclastic markers including cathepsin K and acid phosphatase 5. TsI also reduced inflammatory response and oxidative stress and activated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway in the femoral heads. Taken together, our findings show that TsI can relieve SIONFH, indicating that it may be a candidate for preventing SIONFH.

ox-LDL-Induced Endothelial Progenitor Cell Oxidative Stress via p38/Keap1/Nrf2 Pathway

Background

Nrf2 which was recently reported to regulate the antioxidant genes and cellular redox regulators was highly expressed in EPCs. However, its role in ox-LDL-induced EPC oxidative stress and apoptosis has not been fully illustrated.

Methods

EPCs isolated from human peripheral blood mononuclear cells were treated with different concentrations of ox-LDL, Keap1 siRNA, and a specific p38 MAPK inhibitor SB203580 and then used to assay the cytoplasmic Nrf2, nuclear Nrf2, NAD(P) H:quinone oxidoreductase 1 (NQO1) and Bax/Bcl-2 levels with Western blot, NQO1 mRNA levels with RT-PCR, ROS levels with H2DCF-DA, loss/disruption of mitochondrial membrane potential with JC-1, apoptosis with Annexin V and PI, migration with transwell chambers, and tube formation with Matrigel.

Results

ox-LDL decreased the nuclear Nrf2/Histone H3 to cytoplasmic Nrf2/GAPDH ratio, NQO1 mRNA, and protein levels. ox-LDL enhanced ROS production, induced the loss of membrane potential, and increased the cell shrinkage, pyknotic nuclei, and apoptosis of EPCs. Keap1 siRNA increased Nrf2 nuclear translocation, NQO1 mRNA transcription, and protein expression and prevented ROS generation and formation of JC-1 monomers. ox-LDL increased the activation of p38. SB203580 significantly eliminated ox-LDL induced inhibition of Nrf2 nuclear translocation, depression of NQO1 mRNA transcription, generation of ROS, and formation of JC-1 monomers in EPCs. Keap1 siRNA decreased the Bax/Bcl-2 ratio which was increased by ox-LDL in EPCs. ox-LDL decreased EPC migration and tube formation. Keap1 siRNA preserved the migration and tube formation of EPCs.

Conclusion

ox-LDL activated EPCs p38/Keap1/Nrf2 pathway and induced oxidative stress, dysfunction, and apoptosis of EPCs.

Protective effect of baicalin against arsenic trioxide-induced acute hepatic injury in mice through JAK2/STAT3 signaling pathway

Baicalin (BA) is a kind of flavonoid that is isolated from Scutellaria baicalensis Georgi, which has been verified to have hepatoprotective effects in some diseases. However, the role of BA in acute hepatic injury induced by arsenic trioxide (ATO) remains unclear. The aim of this study was to investigate the protective action of BA on acute hepatic injury induced by ATO and to probe its possible mechanism. Mice were pretreated with BA (50, 100 mg/kg) by gavage. After 7 h, ATO (7.5 mg/kg) was injected intraperitoneally to induce liver injury. After 7 days of treatment, serum and hepatic specimens were collected and assayed to evaluate the hepatoprotective effect of BA. Pathological sections and the liver function index indicated that ATO caused significant liver injury. The fluorescence of reactive oxygen species and oxidative stress indicators showed that ATO also increased oxidative stress. The inflammatory markers in ATO-induced mice also increased significantly. Staining of the terminal deoxynucleotidyl transferase dUTP nick end labeling and apoptotic factor assay showed that apoptosis increased. However, with BA pretreatment, these changes were significantly weakened. In addition, BA treatment promoted the expression of proteins related to the JAK2/STAT3 signaling pathway. The results suggest that BA can ameliorate acute ATO-induced hepatic injury in mice, which is related to the inhibition of oxidative stress, thereby reducing inflammation and apoptosis. The mechanism of this protection is potentially related to the JAK2/STAT3 signaling pathway.

Effect of inorganic mercury exposure on reproductive system of male mice: Immunosuppression and fibrosis in testis

Mercury as a toxic heavy metal will accumulate in the body and induce various diseases through the food chain. However, it is unknown that the detailed mechanism of reproductive disorder induced by inorganic mercury in male mice to date. This study investigated the toxicological effect of mercuric chloride (HgCl₂ ) exposure on reproductive system in male mice. Male Kunming mice received normal saline daily or HgCl₂ (3 mg/kg bodyweight) by intraperitoneal injection for a week. The reproductive function was evaluated, and the HgCl₂ exposure induced the decline of sperm quality, pregnancy rate, mean litter size, and survival rate. Notably, we firstly found the HgCl₂ -induced immunosuppression and fibrosis in mice testis according to the results of RNA sequencing. Collectively, these findings demonstrate that HgCl₂ exposure disrupts the reproductive system and induces testicular immunosuppression and fibrosis via inhibition of the CD74 signaling pathway in male mice.

Anti-inflammatory action of astaxanthin and its use in the treatment of various diseases

Astaxanthin (AST) is a red pigmented carotenoid with significant antioxidant, anti-inflammatory, anti-proliferative, and anti-apoptotic properties. In this study, we summarize the available literature on the anti-inflammatory efficacy of AST in various chronic and acute disorders, such as neurodegenerative, renal-, hepato-, skin- and eye-related diseases, as well as gastrointestinal disorders. In addition, we elaborated on therapeutic efficacy of AST and the role of several pathways, including PI3K/AKT, Nrf2, NF-κB, ERK1/2, JNK, p38 MAPK, and JAK-2/STAT-3 in mediating its effects. However, additional experimental and clinical studies should be performed to corroborate the anti-inflammatory effects and protective effects of AST against inflammatory diseases in humans. Nevertheless, this review suggests that AST with its demonstrated anti-inflammatory property may be a suitable candidate for drug design with novel technology.

Astaxanthin Prevents Diet-Induced NASH Progression by Shaping Intrahepatic Immunity

Dietary change leads to a precipitous increase in non-alcoholic fatty liver disease (NAFLD) from simple steatosis to the advanced form of non-alcoholic steatohepatitis (NASH), affecting approximately 25% of the global population. Although significant efforts greatly advance progress in clarifying the pathogenesis of NAFLD and identifying therapeutic targets, no therapeutic agent has been approved. Astaxanthin (ASTN), a natural antioxidant product, exerts an anti-inflammation and anti-fibrotic effect in mice induced with carbon tetrachloride (CCl₄) and bile duct ligation (BDL); thus, we proposed to further investigate the potential effect of ASTN on a diet-induced mouse NASH and liver fibrosis, as well as the underlying cellular and molecular mechanisms. By treating pre-development of NASH in mice induced with a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD), we have demonstrated that oral administration ASTN preventively ameliorated NASH development and liver fibrosis by modulating the hepatic immune response, liver inflammation, and oxidative stress. Specifically, ASTN treatment led to the reduction in liver infiltration of monocyte-derived macrophages, hepatic stellate cell (HSC) activation, oxidative stress response, and hepatocyte death, accompanied by the decreased hepatic gene expression of proinflammatory cytokines such as TNF-α, TGF-β1, and IL-1β. In vitro studies also demonstrated that ASTN significantly inhibited the expression of proinflammatory cytokines and chemokine CCL2 in macrophages in response to lipopolysaccharide (LPS) stimulation. Overall, in vivo and in vitro studies suggest that ASTN functions as a promising therapeutic agent to suppress NASH and liver fibrosis via modulating intrahepatic immunity.

Toxicological effects of deltamethrin on quail cerebrum: Weakened antioxidant defense and enhanced apoptosis

Deltamethrin is the most common type II synthetic pyrethroid insecticide, and has posed widespread residues to environment. However, whether deltamethrin has potential toxic effects on quail cerebrum remains greatly obscure. Accordingly, we investigated the impact of chronic exposure to deltamethrin on oxidative stress and apoptosis in quail cerebrum. Quails upon 12-week exposure of deltamethrin (0, 15, 30, or 45 mg/kg body weight intragastric administration) were used as a cerebrum injury model. The results showed that deltamethrin treatment led to cerebral injury dose-dependently through the weakened antioxidant defense by downregulating nuclear factor erythroid-2-related factor 2 (Nrf2) and its downstream proteins levels and mRNA expression. Furthermore, deltamethrin treatment induced apoptosis in cerebrum by decreasing B-cell lymphoma gene 2 (Bcl-2) level, as well as increasing Jun N-terminal kinase3, caspase-3, and Bcl-2-associated X protein levels. Simultaneously, toll-like receptor 4 (TLR4) downstream inflammation-related genes or proteins were significantly up-regulated by deltamethrin dose-dependently. Altogether, our study demonstrated that chronic exposure to deltamethrin induces inflammation and apoptosis in quail cerebrums by promoting oxidative stress linked to inhibition of the Nrf2/TLR4 signaling pathway. These results provide a novel knowledge on the chronic toxic effect of deltamethrin, and establish a theoretical foundation for the evaluation of pesticide-induced health risk.

The aggravation of allergic airway inflammation with dibutyl phthalate involved in Nrf2-mediated activation of the mast cells

Dibutyl phthalate (DBP)-an organic pollutant-is ubiquitous in the environment. DBP as an immune adjuvant is related to the development of multiple allergic diseases. However, the current research involving DBP-induced pulmonary toxicity remains poorly understood. Therefore, this research aimed to explore the adverse effect and potential mechanism of DBP exposure on the lungs in rats. In our study, ovalbumin was used to build a rat model of allergic airway inflammation to study any harmful effect of DBP exposure on lung tissues. Rats were treated by intragastric administration of DBP (500 mg kg^-1 or 750 mg kg^-1) and/or subcutaneous injection of SFN (4 mg kg^-1). The results of histopathological analysis, cell count, and myeloperoxidase showed that DBP promoted the inflammatory damage of lungs. In the lung tissues, the detection of terminal deoxynucleotidyl transferase dUNT nick end labeling and oxidative stress indices showed that DBP significantly increased the level of apoptosis and oxidative stress. Western blot analysis indicated that DBP raised the expression level of thymic stromal lymphopoietin and reduced the nuclear expression level of nuclear factor-erythroid-2-related factor 2 (Nrf2), which was further verified by quantitative real-time PCR. Meanwhile, DBP treatment markedly up-regulated the inflammatory cytokines such as IL-4 and IL-13, and rat mast cell protease-2, a marker secreted by mast cells (MCs). Conversely, sulforaphane, a Nrf2 inducer, ameliorated the pulmonary damage induced by DBP in the above. Altogether, our data provides a new insight into the impacts of the activation of MCs on the DBP-induced pulmonary toxicity as well as the safety evaluation of DBP.

Xanthohumol alleviates T2DM-induced liver steatosis and fibrosis by mediating the NRF2/RAGE/NF-κB signaling pathway

Hyperglycemia-associated advanced glycation end products (AGEs) and the receptor for AGE (RAGE) contribute to nonalcoholic fatty liver disease (NAFLD). Xanthohumol (XH) exhibits protective activities against liver diseases. Aim: To investigate the effects of XH on Type II diabetes mellitus (T2DM)-induced liver steatosis and fibrosis. Methods: NAFLD rat models were duplicated. Biomolecular markers were detected. Quantitative real-time PCR (RT-PCR) and western blot were used to detect mRNA and protein expression. Immunofluorescence assays were employed to identify the subcellular locations. Results: XH significantly ameliorated hyperglycemia and hyperlipidemia in rats. XH attenuated the expression of RAGE and NF-κB signaling. XH significantly alleviated inflammation and oxidation by upregulating NRF2 expression. Knockdown of NRF2 blocked XH protection in hepatocytes. Conclusion: XH protected against T2DM-induced liver steatosis and fibrosis by mediating NRF2/AGE/RAGE/NF-κB signaling.

Anti-Inflammatory and Anticancer Effects of Microalgal Carotenoids

Acute inflammation is a key component of the immune system’s response to pathogens, toxic agents, or tissue injury, involving the stimulation of defense mechanisms aimed to removing pathogenic factors and restoring tissue homeostasis. However, uncontrolled acute inflammatory response may lead to chronic inflammation, which is involved in the development of many diseases, including cancer. Nowadays, the need to find new potential therapeutic compounds has raised the worldwide scientific interest to study the marine environment. Specifically, microalgae are considered rich sources of bioactive molecules, such as carotenoids, which are natural isoprenoid pigments with important beneficial effects for health due to their biological activities. Carotenoids are essential nutrients for mammals, but they are unable to synthesize them; instead, a dietary intake of these compounds is required. Carotenoids are classified as carotenes (hydrocarbon carotenoids), such as α- and β-carotene, and xanthophylls (oxygenate derivatives) including zeaxanthin, astaxanthin, fucoxanthin, lutein, α- and β-cryptoxanthin, and canthaxanthin. This review summarizes the present up-to-date knowledge of the anti-inflammatory and anticancer activities of microalgal carotenoids both in vitro and in vivo, as well as the latest status of human studies for their potential use in prevention and treatment of inflammatory diseases and cancer.

Arsenic exposure induces intestinal barrier damage and consequent activation of gut-liver axis leading to inflammation and pyroptosis of liver in ducks

Arsenic is an important hazardous metalloid commonly found in polluted soil, rivers and groundwater. However, few studies exist regarding the effect of arsenic trioxide (ATO) on the gut-liver axis and consequent hepatotoxicity in waterfowl. Here, we investigated the influence of ATO on duck intestines and livers, and explored the role of the gut-liver axis in ATO-induced hepatotoxicity and intestinal toxicity. Our results demonstrated that ATO-exposure induced intestinal damage, liver inflammatory cell infiltration and vesicle steatosis. Additionally, the intestinal microbiota community in ATO-exposed ducks displayed significantly decreased α-diversity and an altered bacterial composition. Moreover, ATO-exposure markedly reduced the expression of intestinal barrier-related proteins (Claudin-1, MUC2, ZO-1 and Occludin), resulting in increased intestinal permeability and elevated lipopolysaccharide levels. Simultaneously, ATO-exposure also upregulated pyroptosis-related index levels in the liver and jejunum, and increased pro-inflammatory cytokine production (IFN-γ, TNF-α, IL-18, and IL-1β). Our further mechanistic studies showed that ATO-induced liver and jejunum inflammation were provoked by the activation of the LPS/TLR4/NF-κB signaling pathway and NLRP3 inflammasome. In summary, these results manifested that ATO exposure can cause liver and jejunal inflammation and pyroptosis, and the indirect gut-liver axis pathway may play an essential role in the potential mechanism of ATO-induced hepatotoxicity.

Pulmonary inflammatory and fibrogenic response induced by graphitized multi-walled carbon nanotube involved in cGAS-STING signaling pathway

Graphitized multi-walled carbon nanotubes (GMWCNTs) are a new type of nanomaterial. Recently, their production and application in biological medicine have grown rapidly. However, GMWCNTs may cause adverse health effects, including the common occupational disease of pulmonary fibrosis. Pulmonary fibrosis is a serious progressive disease that often leads to lung failure, high mortality, and disability, and there is no effective therapy currently available. Therefore, identifying new biomarkers of the disease is important to better understand the disease mechanisms and explore new therapeutic strategies. In this study, 40 μg of GMWCNTs was used to treat mice in vivo by pharyngeal aspiration, and different genes were screened by transcriptome sequencing. Activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) signal pathway had an important effect on the development of pulmonary inflammation and fibrosis. GMWCNTs were then administered to the mice with a STING inhibitor (C-176). Inhibition of STING effectively decreased pulmonary inflammation and fibrosis in mice induced by GMWCNTs. Collectively, activation of the cGAS-STING signaling pathway is involved in GMWCNT-induced pulmonary inflammation and fibrosis in mice.

Inhibition of the Nrf2/p38MAPK pathway involved in deltamethrin-induced apoptosis and fibrosis in quail kidney

Deltamethrin (DLM) is a broad-spectrum and effective pyrethroid insecticide. However, DLM has good residual activity on most surfaces and many insects, so it poses a threat to the environment and health of animals and human. Exposure to DLM can cause kidney injury, but the mechanism is not well understood. Therefore, we investigated the possible mechanism of quail kidney injury induced by chronic exposure to different doses of DLM for 12 weeks. The results showed that chronic exposure to DLM induced apoptosis and fibrosis of quail kidney through the promotion of oxidative stress by down-regulating nuclear factor erythroid 2 related factor 2 (Nrf2), up-regulating the phosphorylation of p38 mitogen-activated protein kinases (p38MAPK). Furthermore, DLM-induced kidney apoptosis in quails as evidenced by increased expression of B-cell lymphoma gene 2-associated X while decreased expression of B-cell lymphoma-extra large. Simultaneously, DLM-induced kidney fibrosis in quails as evidenced by increased expression of fibrosis maker proteins. Overall, the results demonstrate that chronic DLM exposure induces kidney apoptosis and fibrosis via inhibition of the Nrf2/p38MAPK pathway. This study provides a new understanding for the mechanism of DLM-induced quail kidney injury and also provides a theoretical basis for treatment of the DLM poisoning.

Anti-fibrotic activity of sitagliptin against concanavalin A-induced hepatic fibrosis. Role of Nrf2 activation/NF-κB inhibition

Sitagliptin is known for its anti-diabetic activity though it has other pleiotropic pharmacological actions. Its effect against concanavalin A (Con A)-induced hepatic fibrosis has not been investigated yet. Our target was to test whether sitagliptin can suppress the development of Con A-induced hepatic fibrosis and if so, what are the mechanisms involved? Con A (6 mg/kg) was injected once weekly to male Swiss albino mice for four weeks. Sitagliptin was daily administered concurrently with Con A. Results have shown the potent hepatoprotective activity of sitagliptin against Con A-induced hepatitis and fibrosis. That was evident through the amelioration of hepatotoxicity serum parameters (ALT, AST, ALP, and LDH) and the increase in the level of serum albumin in sitagliptin treated mice. Simultaneously, there was amendment of the Con A-induced hepatic lesions and repression of fibrosis in sitagliptin-treated animals. Hydroxyproline, collagen content and the immuno-expression of the fibrotic markers, TGF-β and α-SMA were depressed upon sitagliptin treatment. Sitagliptin suppressed Con A-induced oxidative stress and increased antioxidants. RT-PCR analysis showed enhancement of mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its target genes (GCLc, GCLm, NQO-1, HO-1) by sitagliptin. Furthermore, sitagliptin ameliorated the level and immuno-expression of nuclear factor kappa-B (NF-κB) alongside the immuno-expression of the inflammatory cytokine, TNF-α. Taken together, this study demonstrates the hepatoprotective activity of sitagliptin which may be in part related to enhancement of Nrf2 signaling pathway and inhibition of NF-κB which interact inflammatory response in liver. Sitagliptin might be a new candidate to suppress hepatitis-associated fibrosis.

Luteolin alleviates inorganic mercury-induced kidney injury via activation of the AMPK/mTOR autophagy pathway

Inorganic mercury is a ubiquitous toxic pollutant in the environment. Exposure to inorganic mercury can cause various poisonous effects, including kidney injury. However, no safe and effective treatment for kidney injury caused by inorganic mercury has been found and used. Luteolin (Lut) possesses various beneficial bioactivities. Here, our research aims to investigate the protective effect of Lut on renal injury induced by mercury chloride (HgCl₂) and identify the underlying autophagy regulation mechanism. Twenty-eight 6-8 weeks old Wistar rats were randomly assigned to four groups: control, HgCl₂, HgCl₂ + Lut, and Lut. We performed the determination of oxidative stress and renal function indicators, histopathological analysis, the terminal deoxynucleotidyl transferase-mediated deoxyuracil nucleoside triphosphate nick-end labeling assay to detect apoptosis, western blot detection of autophagy-related protein levels, and atomic absorption method to detect mercury content. Our results showed that Lut ameliorated oxidative stress, apoptosis and restored the autophagy and renal function caused by HgCl₂ in rats. Concretely, the level of nuclear factor E2-related factor, renal adenosine monophosphate-activated protein kinase (AMPK) expression, and autophagy regulation-related proteins levels were down-regulated, and the mammalian target of rapamycin (mTOR) expression was up-regulated by HgCl₂ treatment. However, Lut treatment reversed the above changes. Notably, Lut reduced the accumulation of HgCl₂ in the kidneys and promoted the excretion of HgCl₂ through urine. Collectively, our results demonstrate that Lut can attenuate inorganic mercury-induced renal injury via activating the AMPK/mTOR autophagy pathway. Therefore, Lut may be a potential biological medicine to protect against renal damage induced by HgCl₂.

The link between deacetylation and hepatotoxicity induced by exposure to hexavalent chromium

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Cr(VI) can induce inflammatory, oxidative stress, and apoptosis in rat liver.

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Cr(VI) induces inflammatory response in the liver by inhibiting deacetylation.

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Oxidative stress caused by Cr(VI) is related to the inhibition of deacetylation.

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Cr(VI) aggravates hepatocyte apoptosis by inhibiting deacetylation in rats.

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Cr(VI) induces liver injury via inhibition of the deacetylation of Sirt1.

Introduction

Hexavalent chromium (Cr(VI)), one of the toxic heavy metals, poses a serious threat to human and animal health. Protein acetylation regulates the structure and function of most proteins in a variety of ways. However, the hepatotoxicity of Cr(VI) and whether it is related to deacetylation remains largely unknown.

Objectives

We aimed to explore the link between the deacetylation of silent information regulator two ortholog 1 (Sirt1) and hepatotoxicity induced by Cr(VI) exposure, and to better clarify the biological mechanism of liver injury induced by Cr(VI).

Methods

We established a model of liver injury of K₂Cr₂O₇ by injecting rats intraperitoneally for 35 days continuously and adding resveratrol (Res) to further explore the link between deacetylation and hepatotoxicity.

Results

The results revealed that Cr(VI) induced inflammatory response and apoptosis in hepatocytes. Furthermore, Cr(VI) reduced Sirt1 expression and inhibited the deacetylation of Sirt1 to downstream key transcription factors, including nuclear factor erythroid 2-related factor 2 (Nrf2), Forkhead box O3 (FOXO3), and nuclear factor-kappa B (NF-κB). Conversely, when Res was administered as an activator of Sirt1, the deacetylation of Sirt1 was enhanced, and inflammatory response and apoptosis were significantly alleviated.

Conclusion

In summary, this work firstly demonstrates that Cr(VI) induces liver injury in rat by inhibiting the deacetylation of Sirt1, which is of positive significance for protecting the natural environment and animal health from chronic Cr poisoning.

AST-120 Improves Cardiac Dysfunction in Acute Kidney Injury Mice via Suppression of Apoptosis and Proinflammatory NF-κB/ICAM-1 Signaling

Purpose

Acute kidney injury (AKI) is a devastating disorder associated with considerably high morbidity and mortality. Reports have shown that AST-120, an oral charcoal adsorbent, can reduce oxidative stress by lowering serum indoxyl sulfate levels. The effects of AST-120 and indoxyl sulfate on kidney injury and cardiac dysfunction were investigated in vivo and in vitro.

Patients and Methods

Patients were tracked for enrollment upon receiving a diagnosis of AKI. Plasma was collected to determine the renal and inflammatory parameters. Renal ischemia/reperfusion (I/R) induced AKI or sham operation was performed in C57BL/6J mice. Animals were divided into sham, AKI+vehicle, and AKI+AST-120 groups. Plasma and tissues were assembled after 48 h to assess apoptotic and inflammatory responses. We also conducted human umbilical vein endothelial cell (HUVECs) and HL-1 cardiomyocyte culture studies to determine the underlying mechanisms of indoxyl sulfate’s effects. Echocardiography, histopathology, biochemical indexes, ELISA, terminal dUTP nick-end labeling (TUNEL) and Western blot analysis were performed.

Results

The cohort included 25 consecutive patients with AKI and 25 non-AKI. Plasma levels of creatinine, indoxyl sulfate, IL-1β and ICAM-1 were significantly higher in patients with AKI than in non-AKI controls. Plasma levels of blood urea nitrogen, creatinine, indoxyl sulfate, IL-1β and renal tubular injury were increased in mice after renal I/R and were decreased by AST-120 treatment. In addition, AST-120 therapy not only improved the parameters assessed by echocardiography but also substantially attenuated the elevation of plasma BNP. Oral administration of AST-120 significantly downregulated NF-κB/ICAM-1 expression and reduced cell apoptosis in both kidney and heart after renal I/R injury.

Conclusion

Our investigations demonstrated that AST-120 administration improves cardiac dysfunction in AKI mice via the suppression of apoptosis and proinflammatory NF-κB/ICAM-1 signaling.

Hexavalent chromium induced heart dysfunction via Sesn2-mediated impairment of mitochondrial function and energy supply

Hexavalent chromium (Cr(VI)), the most toxic valence state of chromium, is widely present in industrial effluents and wastes. Although previous study has reported that Cr(VI) can cause cytomembrane structure impairment by aggravating lipid peroxidation in the heart, the detailed mechanism of Cr(VI)-induced heart dysfunction is still unclear. Sesn2, a novel antioxidant and stress-inducible molecule, is evidenced to protect against various cardiometabolic diseases such as atherosclerosis and cardiomyopathy. To define the potential mechanism of heart dysfunction induced by chronic Cr(VI) exposure, Wistar rats were intraperitoneal injected with potassium dichromate (K₂Cr₂O₇) for 35 d in the present study. The data showed that chronic K₂Cr₂O₇ exposure caused dose-dependently hematological variations, oxidative stress, dysfunction, and disorganized structure of heart, cardiomyocyte apoptosis, ATP depletion, and mitochondria impairment in rats. In addition, the expressions of Drp1 and Bax were increased by K₂Cr₂O₇. However, the suppression of Mfn2, PGC-1α, Sesn2, nuclear Nrf2, HO-1, and NQO1 protein levels was observed in K₂Cr₂O₇-treated rat hearts. In conclusion, these results demonstrate that chronic K₂Cr₂O₇ exposure dose-dependently causes heart dysfunction, and the molecular mechanism of this event is associated with the loss of Sesn2 mediated mitochondrial function and energy supply impairment.