Polyethylene microplastics affect the distribution of gut microbiota and inflammation development in mice

Environmental pollution caused by plastics has become a public health problem. However, the effect of microplastics on gut microbiota, inflammation development and their underlying mechanisms are not well characterized. In the present study, we assessed the effect of exposure to different amounts of polyethylene microplastics (6, 60, and 600 μg/day for 5 consecutive weeks) in a C57BL/6 mice model. Treatment with a high concentration of microplastics increased the numbers of gut microbial species, bacterial abundance, and flora diversity. Feeding groups showed a significant increase in Staphylococcus abundance alongside a significant decrease in Parabacteroides abundance, as compared to the blank (untreated) group. In addition, serum levels of interleukin-1α in all feeding groups were significantly greater than that in the blank group. Of note, treatment with microplastics decreased the percentage of Th17 and Treg cells among CD4⁺ cells, while no significant difference was observed between the blank and treatment groups with respect to the Th17/Treg cell ratio. The intestine (colon and duodenum) of mice fed high-concentration microplastics showed obvious inflammation and higher TLR4, AP-1, and IRF5 expression. Thus, polyethylene microplastics can induce intestinal dysbacteriosis and inflammation, which provides a theoretical basis for the prevention and treatment of microplastics-related diseases.

LncRNAs H19 and HULC, activated by oxidative stress, promote cell migration and invasion in cholangiocarcinoma through a ceRNA manner

Background

Long non-coding RNAs (lncRNAs) are known to play important roles in different cell contexts, including cancers. However, little is known about lncRNAs in cholangiocarcinoma (CCA), a cholangiocyte malignancy with poor prognosis, associated with chronic inflammation and damage to the biliary epithelium. The aim of the study is to identify if any lncRNA might associate with inflammation or oxidative stress in CCA and regulate the disease progression.

Methods

In this study, RNA-seqs datasets were used to identify aberrantly expressed lncRNAs. Small interfering RNA and overexpressed plasmids were used to modulate the expression of lncRNAs, and luciferase target assay RNA immunoprecipitation (RIP) was performed to explore the mechanism of miRNA-lncRNA sponging.

Results

We firstly analyzed five available RNA-seqs datasets to investigate aberrantly expressed lncRNAs which might associate with inflammation or oxidative stress. We identified that two lncRNAs, H19 and HULC, were differentially expressed among all the samples under the treatment of hypoxic or inflammatory factors, and they were shown to be stimulated by short-term oxidative stress responses to H₂O₂ and glucose oxidase in CCA cell lines. Further studies revealed that these two lncRNAs promoted cholangiocyte migration and invasion via the inflammation pathway. H19 and HULC functioned as competing endogenous RNAs (ceRNAs) by sponging let-7a/let-7b and miR-372/miR-373, respectively, which activate pivotal inflammation cytokine IL-6 and chemokine receptor CXCR4.

Conclusions

Our study revealed that H19 and HULC, up-regulated by oxidative stress, regulate CCA cell migration and invasion by targeting IL-6 and CXCR4 via ceRNA patterns of sponging let-7a/let-7b and miR-372/miR-373, respectively. The results suggest that these lncRNAs might be the chief culprits of CCA pathogenesis and progression. The study provides new insight into the mechanism linking lncRNA function with CCA and may serve as novel targets for the development of new countermeasures of CCA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0348-0) contains supplementary material, which is available to authorized users.

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

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

Resveratrol Ameliorates Diabetes-Induced Cardiac Dysfunction Through AT1R-ERK/p38 MAPK Signaling Pathway

The present study was to determine the preventive effect of resveratrol (Res) on diabetes-induced cardiac dysfunction and the possible signaling pathway involved. Diabetes was induced in rats by injection of streptozotocin (STZ) at 45 mg/kg. The animals were randomly divided into three groups (10 rats/group): normal group, diabetes groups with or without Res (80 mg/kg) treatment. Biochemistry, cardiac function and fibrosis were detected. Moreover, pro-inflammatory cytokines were evaluated, and heart tissues were homogenized for western blot analysis to analyze the possible mechanisms. The results indicated that Res might regulate glucose and lipid metabolism, ameliorate cardiac function and fibrosis response in STZ-induced diabetic rats. The protective effects were consistent with the inhibition of inflammatory factors such as TNF-α, IL-6 and IL-1β. In addition, Res favorably shifted STZ-induced AT1R, ERK1/2 and p38 MAPK activation in rat heart. In conclusion, the results suggested that Res attenuated diabetes-induced cardiac dysfunction, and the effects were associated with attenuation inflammatory response and down-regulation of AT1R-ERK/p38 MAPK signaling pathway.

MiR-128-3p mediates TNF-α-induced inflammatory responses by regulating Sirt1 expression in bone marrow mesenchymal stem cells

Tumor Necrosis Factor α (TNF-α), a multifunctional pro-inflammatory cytokine, is produced by macrophages/monocytes during acute inflammation, and plays a critical role in orchestrating the cytokine cascade in various inflammatory diseases. Previous studies demonstrated that TNF-α induces inflammatory responses in bone marrow mesenchymal stem cells (BMSCs) transplantation, leading to unsatisfactory effects and limit the clinical use of BMSCs. MicroRNAs are reported to involve in inflammation by regulating the expression of their targets in inflammatory response pathway. However, whether microRNAs mediate TNF-α-induced inflammatory responses in BMSCs remains elusive. Here, we found that TNF-α treatment induced an inflammatory response by increasing the levels of key inflammatory mediators, including IL-6, IL-1β, matrix metalloproteinase 9 (MMP9) and monocyte chemotactic protein-1 (MCP-1) in BMSCs. Moreover, real-time PCR result showed dramatically up-regulation of miR-128-3p after exposure to TNF-α. Interestingly, miR-128-3p over-expression exacerbated the TNF-α-induced inflammatory response, while suppression of miR-128-3p effectively eliminated the inflammatory response in BMSCs. Bioinformatic analysis identified sirtuin 1 is a direct target of miR-128-3p. Up-regulation of sirtuin 1 induced by resveratrol also diminished the TNF-α-induced inflammatory response in BMSCs. Altogether, our results indicated that miR-128-3p targets sirtuin 1 to mediate the TNF-α-induced inflammatory response in BMSCs, which may provide new strategies to protect against inflammatory-dependent impairments in BMSCs.

The combination of systemic inflammation-based marker NLR and circulating regulatory T cells predicts the prognosis of resectable pancreatic cancer patients

BACKGROUND

The systemic inflammation response and immune impairment are closely related to the development and progression of various tumours, such as pancreatic cancer. In this study, we evaluated circulating inflammation factors and circulating regulatory T cells (Tregs) as markers of immunosuppression in a cohort of Chinese patients with resectable pancreatic cancer.

METHODS

Samples were retrospectively collected from a series of 195 pathological stage I/II pancreatic cancer patients who underwent potentially curative surgery between June 2010 and April 2014. To examine the prognostic factors, circulating systemic inflammation-based markers and Tregs, detected by flow cytometry, were analysed.

RESULTS

Univariate analyses revealed that the neutrophil-lymphocyte ratio (NLR), TNM stage, differentiation, chemotherapy, CA19-9 levels and presence of Tregs are significantly associated with overall survival in patients with resectable pancreatic cancers. NLR (p = 0.001, HR = 0.538), TNM stage (p = 0.004, HR = 0.593), differentiation (p = 0.011, HR = 0.46), chemotherapy (p = 0.006, HR = 0.516) and Tregs (p = 0.001, HR = 0.558) are identified as independent prognostic markers by multivariate analyses. Interestingly, we also found that high NLR levels combined with a high proportion of Tregs (p < 0.001, HR = 3.521) correlate strongly with worse survival, with a greater than 3.5-fold increased risk of death compared with those with concurrent low levels of NLR and Tregs.

CONCLUSIONS

The preoperative NLR and circulating regulatory T cells are potentially independent prognostic factors for overall survival in resectable pancreatic cancer patients. High NLR levels combined with poor immune state before surgery, as measured by Tregs, are associated with an extremely poor prognosis.

miR-192 targeting IL-1RI regulates the immune response in miiuy croaker after pathogen infection in vitro and in vivo

Activation of innate and acquired immune responses is regulated by detailed mechanisms to control their onset and termination. MicroRNAs have been implicated as negative regulators controlling the diverse of biophysical and biochemical processes at the post-transcriptional level. However, the physiological roles of miRNAs in aquatic organisms are largely unclear. In this study, we explored the potential roles of mmi-miR-192 in regulating interleukin 1 receptor type I (IL-1RI) involved in immune and inflammatory response in miiuy croakers. This was further evaluated by negative expression profiles in both LPS exposure macrophages and Vibrio anguillarum challenged miiuy croaker. By means of promoter analysis, mmi-miR-192 was found to be an AP-1 dependent gene. Importantly, the dual luciferase reporter assay presented the regulation between mmi-miR-192 and IL-1RI. The result of miiuy croaker miR-192 reduced the wild-type IL-1RI but not the mutant one luciferase levels suggested that mmi-miR-192 modulated IL-1RI expression by directly targeting the 3'UTR of IL-1RI mRNA. Overall, our study revealed the mechanism that the miR-192-IL1RI pathway regulated bacteria infection in miiuy croakers.

Gene expression profiles in peripheral blood mononuclear cells of SARS patients

AIM: To investigate the role of inflammatory and anti-viral genes in the pathogenesis of SARS.

METHODS: cDNA microarrays were used to screen the gene expression profiles of peripheral blood mononuclear cells (PBMCs) in two SARS patients (one in the acute severe phase and the other in the convalescent phase) and a healthy donor. In addition, real-time qualitative PCR was also performed to verify the reproducibility of the microarray results. The data were further analyzed.

RESULTS: Many inflammatory and anti-viral genes were differentially expressed in SARS patients. Compared to the healthy control or the convalescent case, plenty of pro-inflammatory cytokines such as IL-1, TNF-α, IL-8, and MAPK signaling pathway were significantly upregulated in the acute severe case. However, anti-inflammatory agents such as IL-4 receptor, IL-13 receptor, IL-1Ra, and TNF-α-induced proteins 3 and 6 also increased dramatically in the acute severe case. On the contrary, a lot of IFN-stimulated genes like PKR, GBP-1 and 2, CXCL-10 and 11, and JAK/STAT signal pathway were downregulated in the acute severe case compared to the convalescent case.

CONCLUSION: Gene expression in SARS patients mirrors a host state of inflammation and anti-viral immunity at the transcription level, and understanding of gene expression profiles may make contribution to further studies of the SARS pathogenesis.

Inhibitory effects of hyperoside on lung cancer by inducing apoptosis and suppressing inflammatory response via caspase-3 and NF-κB signaling pathway

Lung cancer is one of the most common malignancies in the world and the most threatening cancer to human health. Effective therapies based on non-cytotoxic induction in cell inflammation- and apoptosis-responsive pathways are thought to represent a novel advance in treating lung cancer. However, many studies are still required for effective pharmaceutical to induce cancer cell death. Hyperoside (Hyp) is the chief component of some Chinese herbs with anticancer effect. Here, we investigated the role of hyperoside on the lung cancer cell migration, invasion, inflammation and apoptosis in A549 cells in vitro and xenografts of nude mice in vivo. A549 cells were injected in nude mice for establishing tumors. Our results showed that hyperoside suppressed the proliferation, migration and invasion. Additionally, apoptosis was induced by hyperoside via Bcl-2/Bax-regulated Caspase3 activation, suggesting that hyperoside might inhibit lung cancer progression through apoptotic induction. And also, hyperoside could prevent progression and development of lung cancer through inactivating NF-κB signaling pathway. Subsequently, inflammatory cytokines, including TNF-α, IL-6, IL-1β and IL-18, were down-regulated significantly. And animal experiments also illustrated that the tumor volume and weight were reduced after hyperoside administration, which was also through apoptosis induction and prevention of inflammation response by Caspase3 activation and NF-κB inactivation. To our knowledge, it was the first time to evaluate the effects of hyperoside on preventing progression and development of lung cancer in vivo and in vitro to assess the possible therapies of hyperoside as a future approach for preventing lung cancer progression and development.

Effect of Shikonin on Spinal Cord Injury in Rats Via Regulation of HMGB1/TLR4/NF-kB Signaling Pathway

BACKGROUND/AIMS

Shikonin, a compound extracted from Zicao, has been demonstrated to hold anti-bacterial, anti-inflammatory, and anti-tumor activities in various diseases and it has been shown to protect human organs from injuries. However, the effect of shikonin on the recovery of spinal cord injury (SCI) remains unknown. This study was designed to estimate the potential therapeutic effect and underlying mechanism of shikonin on SCI in vivo.

METHODS

In the study, we used HE staining, ELISA assay, transfection assay, TUNEL assay, real time PCR and Western blot to detect the effects of shikonin on spinal cord injury in rats.

RESULTS

we showed that shikonin could promote the recovery of motor function and tissue repair after SCI treatment in rats SCI model. Moreover, we demonstrated that shikonin inhibited the spinal cord edema in SCI model of rats. According to further investigation, shikonin induced the reduction of inflammatory response through decreasing the expression levels of HMGB1, TLR4 and NF-κB after SCI injury. In addition, we also found that shikonin could suppress the apoptosis and expression of caspase-3 protein in SCI model of rats.

CONCLUSION

Our results demonstrated that shikonin induced the recovery of tissue repair and motor function via inactivation of HMGB1/TLR4/NF-κB signaling pathway in SCI model of rats. Meanwhile, shikonin regulated the inflammation response in SCI by suppressing the HMGB1/TLR4/NF-κB signaling pathway. The described mechanism sheds novel light on molecular signaling pathway in spinal cord injury and secondary injury including inflammatory response.

Effects of calcitriol (1, 25-dihydroxy-vitamin D3) on the inflammatory response induced by H9N2 influenza virus infection in human lung A549 epithelial cells and in mice

Background

H9N2 influenza viruses circulate globally and are considered to have pandemic potential. The hyper-inflammatory response elicited by these viruses is thought to contribute to disease severity. Calcitriol plays an important role in modulating the immune response to viral infections. However, its unknown whether calcitriol can attenuate the inflammatory response elicited by H9N2 influenza virus infection.

Methods

Human lung A549 epithelial cells were treated with calcitriol (100 nM) and then infected with an H9N2 influenza virus, or infected and then treated with calcitriol (30 nM). Culture supernatants were collected every 24 h post infection and the viral growth kinetics and inflammatory response were evaluated. Calcitriol (5 mg/kg) was administered daily by intraperitoneal injection to BABL/c mice for 15 days following H9N2 influenza virus infection. Mice were monitored for clinical signs of disease, lung pathology and inflammatory responses.

Results

Calcitriol treatment prior to and post infection with H9N2 influenza significantly decreased expression of the influenza M gene, IL-6, and IFN-β in A549 cells, but did not affect virus replication. In vivo, we found that calcitriol treatment significantly downregulated pulmonary inflammation in mice 2 days post-infection, but increased the inflammatory response 4 to 6 days post-infection. In contrast, the antiviral cytokine IFN-β was significantly higher in calcitriol-treated mice than in the untreated infected mice at 2 days post-infection, but lower than in untreated infected mice on days 4 and 8 post-infection. The elevated levels of pro-inflammatory cytokines and the decreased levels of antiviral cytokine are consistent with the period of maximum body weight loss and the lung damage in calcitriol-treated mice.

Conclusions

These results suggest that calcitriol treatment might have a negative impact on the innate immune response elicited by H9N2 infection in mice, especially at the later stage of influenza virus infection. This study will provide some novel insights into the use of calcitriol to modulate the inflammatory response elicited by influenza virus infection in humans.

Phylogenetic analysis of the caspase family in bivalves: implications for programmed cell death, immune response and development

BACKGROUND

Apoptosis is an important process for an organism's innate immune system to respond to pathogens, while also allowing for cell differentiation and other essential life functions. Caspases are one of the key protease enzymes involved in the apoptotic process, however there is currently a very limited understanding of bivalve caspase diversity and function.

RESULTS

In this work, we investigated the presence of caspase homologues using a combination of bioinformatics and phylogenetic analyses. We blasted the Crassostrea gigas genome for caspase homologues and identified 35 potential homologues in the addition to the already cloned 23 bivalve caspases. As such, we present information about the phylogenetic relationship of all identified bivalve caspases in relation to their homology to well-established vertebrate and invertebrate caspases. Our results reveal unexpected novelty and complexity in the bivalve caspase family. Notably, we were unable to identify direct homologues to the initiator caspase-9, a key-caspase in the vertebrate apoptotic pathway, inflammatory caspases (caspase-1, - 4 or - 5) or executioner caspases-3, - 6, - 7. We also explored the fact that bivalves appear to possess several unique homologues to the initiator caspase groups - 2 and - 8. Large expansions of caspase-3 like homologues (caspase-3A-C), caspase-3/7 group and caspase-3/7-like homologues were also identified, suggesting unusual roles of caspases with direct implications for our understanding of immune response in relation to common bivalve diseases. Furthermore, we assessed the gene expression of two initiator (Cg2A, Cg8B) and four executioner caspases (Cg3A, Cg3B, Cg3C, Cg3/7) in C. gigas late-larval development and during metamorphosis, indicating that caspase expression varies across the different developmental stages.

CONCLUSION

Our analysis provides the first overview of caspases across different bivalve species with essential new insights into caspase diversity, knowledge that can be used for further investigations into immune response to pathogens or regulation of developmental processes.

Induction of lipid metabolism dysfunction, oxidative stress and inflammation response by tris(1-chloro-2-propyl)phosphate in larval/adult zebrafish

As an important organophosphate flame retardant, tris(1-chloro-2-propyl)phosphate (TCPP) is ubiquitous in the environment leading to inevitable human exposure. However, there is a paucity of information regarding its acute/chronic effects on obesity, lipid homeostasis, and hepatocellular carcinoma, especially regarding the underlying molecular mechanisms in humans. Herein, we investigated the effects of TCPP exposure (5-25 mg/L) on lipid homeostasis in larval and adult zebrafish (Danio rerio). TCPP exposure caused remarkable lipid-metabolism dysfunction, which was reflected in obesity and excessive lipid accumulation in zebrafish liver. Mechanistically, TCPP induced the over-expression of adipogenesis genes and suppressed the expression of fatty-acid β-oxidation genes. Consequently, excess lipid synthesis and deficient expenditure triggered oxidative damage and an inflammation response by disrupting the antioxidant system and over-expressing proinflammatory cytokine. Based on high-throughput transcriptome sequencing, we found that TCPP exposure led to enrichment of several pathways involved in lipid metabolism and inflammation, as well as several genes related to pathways of cancer. Notably, increasing expressions of Ki-67 and 53BP1 proteins, which are reliable biomarkers for recognition and risk prediction of cellular proliferation in cancer cells, were observed in liver tissues of adult zebrafish. These results imply that chronic TCPP exposure triggers a potential risk of hepatocellular carcinogenesis (HCC) progression. Collectively, these findings offer new insights into our mechanistic understanding for the health effects of organophosphorus flame retardants on humans.

Luteolin Ameliorates Cognitive Impairments by Suppressing the Expression of Inflammatory Cytokines and Enhancing Synapse-Associated Proteins GAP-43 and SYN Levels in Streptozotocin-Induced Diabetic Rats

Luteolin, a flavonoid isolated from Cirsium japonicum, has antioxidant, anti-inflammatory and neuroprotective activities. Our previous studies brought a prospect that luteolin benefited diabetic rats with cognitive impairments. In this study, we examined whether luteolin could suppress the inflammatory cytokines, thus increasing synapse-associated proteins in streptozotocin (STZ)-induced diabetes in rat models. The model rats underwent luteolin treatment for 8 consecutive weeks, followed by assessment of cognitive performances with MWM test. Nissl staining was employed to assess the neuropathological changes in the hippocampus and the effects of luteolin on diabetic rats. With animals sacrificed, expressions of inflammatory cytokines including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) and synapse-associated proteins including growth-associated protein-43 (GAP-43) and synaptophysin (SYN) were determined. The results affirmed improvement of behavioral performances in the MWM test, downexpression of glycation end products (AGEs) in the plasma and the receptor for advanced glycation end products in the hippocampus, inhibition of IL-1β and TNF-α in both the hippocampus and plasma in diabetic rats. Furthermore, luteolin treatment upregulated the expressions of GAP-43 and SYN in the hippocampus. Thus, luteolin could ameliorate the cognitive dysfunctions in STZ-induced diabetic rat model.

Fis1 deficiencies differentially affect mitochondrial quality in skeletal muscle

Mitochondrial dynamics and mitophagy are important aspects of mitochondrial quality control, and are linked to neurodegenerative diseases and muscular diseases. Fis1, a protein on the mitochondrial outer membrane, is thought to mediate mitochondrial fission. However, Fis1 null worms and mammalian cells only display mild fission defects but show aberrant mitophagy. To assess Fis1 function in vivo, we generated conditional knock-out Fis1 mice to allow for specific Fis1 deletion in adult skeletal muscle. In the absence of Fis1 in Type I muscle, mitochondrial hyperfusion, respiratory chain deficiency, and increased mitophagy were found. Moreover, abnormal mitophagy was aggravated by endurance exhaustive exercise stress (EEE), suggesting that Fis1 is involved in maintaining normal mitophagy in mitochondria-rich Type I muscle during exercise. Additionally, Fis1 loss induced delayed onset muscle ultrastructure change (DOMUC) in Type I muscle and strong inflammation in response to acute exhaustive exercise (EE). Thus, we identify a role for Fis1 in maintaining normal mitochondrial structure and function at rest and under exercise stress.

Low or excess levels of dietary cholesterol impaired immunity and aggravated inflammation response in young grass carp (Ctenopharyngodon idella)

The present study explored the effect of cholesterol on the immunity and inflammation response in the immune organs (head kidney, spleen and skin) of young grass carp (Ctenopharyngodon idella) fed graded levels of dietary cholesterol (0.041-1.526%) for 60 days and then infected with Aeromonas hydrophila for 14 days. The results showed that low levels of cholesterol (1) depressed the innate immune components [lysozyme (LZ), acid phosphatase (ACP), complements and antimicrobial peptides] and adaptive immune component [immunoglobulin M (IgM)], (2) up-regulated the mRNA levels of pro-inflammatory cytokines [interleukin 1β (IL-1β), IL-6, IL-8, IL-12p35, IL-12p40, IL-15, IL-17D, tumor necrosis factor α (TNF-α) and interferon γ2 (IFN-γ2)], partly due to the activated nuclear factor kappa B (NF-κB) signalling, and (3) down-regulated the mRNA levels of anti-inflammatory cytokines [IL-4/13B, IL-10, IL-11, transforming growth factor (TGF)-β1 and TGF-β2], partly due to the suppression of target of rapamycin (TOR) signalling in the immune organs of young grass carp. Interestingly, dietary cholesterol had no influences on the IκB kinase α (IKKα) and IL-4/13A mRNA levels in the head kidney, spleen and skin, the IL-1β and IL-12p40 mRNA levels in the spleen and skin, or the β-defensin-1 mRNA level in the skin of young grass carp. Additionally, low levels of cholesterol increased the skin haemorrhage and lesion morbidity. In summary, low levels of cholesterol impaired immunity by depressing the innate and adaptive immune components, and low levels of cholesterol aggravated the inflammation response via up-regulating the expression of pro-inflammatory cytokines as well as down-regulating the expression of anti-inflammatory cytokines partly through the modulation of NF-κB and TOR signalling in the immune organs of fish. Similar to the low level of cholesterol, the excess level of dietary cholesterol impaired immunity and aggravated inflammation response in the immune organs of fish. Finally, based on the percent weight gain (PWG), the ability against skin haemorrhage and lesions as well as the LZ activity in the head kidney and the ACP activity in the spleen, the optimal dietary cholesterol levels for young grass carp were estimated as 0.721, 0.826, 0.802 and 0.772% diet, respectively.

Dietary fenofibrate attenuated high-fat-diet-induced lipid accumulation and inflammation response partly through regulation of pparα and sirt1 in juvenile black seabream (Acanthopagrus schlegelii)

An 8-week feeding trail was conducted in Acanthopagrus schlegelii with an initial body weight of 8.34 ± 0.01g. Three isonitrogenous diets were formulated, (1) Control: medium-fat diet (12%); (2) HFD: high-fat diet (18%); (3) HFD + FF: high-fat diet with fenofibrate (0.15%). Liver histological analysis revealed that, compared to HFD, vacuolar fat drops were smaller and fewer in fish fed fenofibrate. Expression of lipid catabolism regulator peroxisome proliferator-activated receptor alpha (pparα) was up-regulated by fenofibrate compared with HFD. In addition, fenofibrate significantly increased the expression level of silent information regulator 1 (sirt1). Meanwhile, the expression level of anti-inflammatory cytokine interleukin 10 (il-10) in intestine was up-regulated, while pro-inflammatory cytokine interleukin 1β (il-1β) in liver and intestine were down-regulated by dietary fenofibrate supplementation. Overall, the present study indicated that fenofibrate reduced fat deposition and attenuated inflammation response caused by HFD partly through a pathway involving regulation of pparα and sirt1.

Fumonisins B1 exposure triggers intestinal tract injury via activating nuclear xenobiotic receptors and attracting inflammation response

Fumonisins (FBs) are mycotoxins that are widely distributed in crops and feed, and ingestion of FBs -contaminated crops is harmful to animal health. Furthermore, it is unknown if Fumonisins B1 (FB1) can cause intestinal toxicity. To investigate FB1-induced intestinal toxicity, mice were treated with 0 or 5 mg/kg FB1 by gavage administration for 42 days. Histopathology indicated that FB1 exposure caused proliferation of intestinal epithelial cells, intestinal villi and epithelial layer shedding, intestinal gland atrophy, and necrosis. Notably, FB1 interfered with nuclear xenobiotic receptors (NXR) homeostasis by regulating the level of aryl hydrocarbon receptor (AHR), constitutive androstane receptor (CAR), pregnane X receptor (PXR) and downstream target genes (CYP450s). Moreover, abnormal expression of inflammatory cytokines (IL-1β, IL-2, IL-4, IL-10, and TNF-α) indicated the occurrence of inflammation. The present study provides new insights regarding the mechanism of FB1-induced intestinal toxicity through activating the NXR system and by triggering inflammatory responses in the intestinal tract in mice.

Grape seed proanthocyanidin extract ameliorates hepatic lipid accumulation and inflammation in grass carp (Ctenopharyngodon idella)

Hepatic lipid metabolism disorder due to excessive fat accumulation in fish is a significant problem in aquaculture. Studies have shown that grape seed procyanidin extract (GSPE) can regulate fish lipid metabolism and improve fish immunity. However, the mechanism is unclear. In this study, we used grass carp that stores excess fat in the liver as a model. In vitro, GSPE treatment of hepatocytes for 3 h significantly decreased TG content, accompanied with decreased expression of SREBP-1c, FAS, and ACC and increased expression of PPARα, ATGL, and LPL. GSPE treatment for 1 h significantly decreased expression of pro-inflammatory cytokines (TNFα, IL-6, IL-1β, and NF-κB) and increased the expression of anti-inflammatory cytokines (IL-10 and TGF-β1). In vivo, the administration of GSPE significantly reduced high-fat diet-induced increase of serum CHOL, TG, and HDL, but increased LDL content. GSPE treatment for 3 h increased expression of ATGL and LPL, and significantly decreased the expression of HFD-fed-induced SREBP-1c, ACC, FAS, PPARγ, PPARα, and H-FABP. GSPE treatment for 3 h also significantly decreased the expression of pro-inflammatory cytokines (TNFα, IL-6, and IL-1β) and increased the expression of the anti-inflammatory cytokine IL-10. The expression levels of the lipogenic miRNAs, miR-33, and miR-122, were suppressed both in vivo and in vitro by GSPE. In summary, GSPE had hypolipidemic and potential anti-inflammatory effects in the liver, potentially mediated by miR-33 and miR-122.

Inhibition of ER stress-activated JNK pathway attenuates TNF-α-induced inflammatory response in bone marrow mesenchymal stem cells

Bone marrow mesenchymal stem cells (BMMSCs) are characterized by their pluripotent differentiation and self-renewal capability and have been widely applied in regenerative medicine, gene therapy, and tissue repair. However, inflammatory response after BMMSCs transplantation was found to impair the osteogenic differentiation of BMMSCs. Thus, understanding the mechanisms underlying inflammation response will benefit the clinical use of BMMSCs. In this study, using a cell model of TNF-α-induced inflammatory response, we found that TNF-α treatment greatly elevated intracellular oxidative stress and induced endoplasmic reticulum (ER) stress by elevating the expression levels of ER sensors, such as PERK, ATF6 and IRE1A. Oxidative stress and ER stress formed a feedback loop to mediate TNF-α-induced inflammation response in BMMSCs. Moreover, c-Jun N-terminal kinase (JNK) signal pathway that coupled to the ER stress was significantly activated by increasing its phosphorylation upon TNF-α treatment. Importantly, pharmacological inhibition of ER stress effectively eliminated the phosphorylation of JNK and attenuated the TNF-α-induced inflammation response. In conclusion, our results indicated that TNF-α induced oxidative and ER stress, thereby leading to JNK activation, and generating inflammation response in BMMSCs. This pathway underlying TNF-α-induced inflammation response may provide new strategies to improve BMMSCs osteogenesis and other inflammation-associated bone diseases.

Simplified α2-macroglobulin as a TNF-α inhibitor for inflammation alleviation in osteoarthritis and myocardial infarction therapy

Tumor necrosis factor α (TNF-α) is a leading proinflammatory cytokine as the master regulator of inflammation in chronic inflammation diseases. Although TNF-α antagonists such as small molecules and peptides are in development, comparable effectiveness in TNF-α neutralization is hardly achieved only with TNF-α capture. In this study, simplified α2-macroglobulin (SM) as a novel TNF-α inhibitor was fabricated to relieve inflammation response by TNF-α capture and internalization with lysosomal degradation. SM was prepared by conjugating a TNF-α-targeting peptide with a receptor binding domain (RBD) derived from α2-macroglobulin through a synthetic biology strategy. SM exhibited effective capture and bioactivity inhibition of TNF-α. Improved endocytosis of TNF-α into lysosomes was observed with SM in macrophages. Even challenged with LPS/IFNγ, the macrophages showed relieved inflammation response with SM treatment. When administrated in chronic inflammation injury in vivo, SM achieved comparable therapeutic efficacy with Infliximab, showing ameliorated cartilage degeneration with relieved inflammation in osteoarthritis (OA) and preserved cardiac function with mitigated myocardium injury in myocardial infarction (MI). These results suggest that SM functioning in TNF-α capture-internalization mechanism might be promising therapeutic alternatives of TNF-α antibodies.

Activation of NF-κB pathways mediating the inflammation and pulmonary diseases associated with atmospheric methylamine exposure

The effects of methylamine on human health have been debated for several years, but the exact adverse outcomes and definite signaling cascades have not been elucidated yet. Herein, a NF-κB signal pathway, a positive regulator of inflammation was identified as the main pathway of methylamine exposure induced adverse effects in bronchial airway cells (16HBE) for the first time. The results indicated that methylamine could stimulate the overproduction of reactive oxygen species (ROS) in cytoplasm and mitochondria of 16HBE cells. Moreover, ROS accelerate the translocation and phosphorylation of NF-κB in nucleic and promote the expression of inflammatory, such as IL-8 and IL-6. As a result, methylamine was found to be increased ROS-mediated NF-κB activation in cells, leading to the production of inflammatory cytokine. Furthermore, the results also showed that methylamine could affect the expression of cytokines related genes, p53, STAT3, Bcl2, c-myc, Cyclin D, Hes1, Mcl-1, TGF-β2. The breakdown of those cell proliferation and apoptosis related genes were leading to a common toxic mechanism of cell death. In summary, our work uncovers a mechanism by which methylamine can induce the formation of inflammation response and demonstrates potential inflammation and carcinogenesis in human airway cell upon the methylamine inhaled.

Vibrio parahaemolyticus Infection Influenced Trace Element Homeostasis, Impaired Antioxidant Function, and Induced Inflammation Response in Litopenaeus vannamei

Vibrio parahaemolyticus (V. parahaemolyticus) caused huge diseases and economic losses in shrimp aquaculture. Understanding the infection mechanism might help develop new strategies for controlling pathogen outbreak. Redistribution of trace element homeostasis, accompanied by impairment of antioxidant status and immune response, was observed during various infections. Accordingly, we hypothesized that V. parahaemolyticus infection might influence trace element homeostasis, impair antioxidant function, and induce inflammation response in shrimp. In the present study, the aim of this study was to investigate the influence of V. parahaemolyticus infection on trace element homeostasis, antioxidant status, and inflammation response in Litopenaeus vannamei (L. vannamei). The results showed that compared with the control group, V. parahaemolyticus infection significantly increased (P < 0.05) intestinal V. parahaemolyticus number, serum copper (Cu) concentration at 24, 48, and 72 h and significantly increased (P < 0.05) serum zinc (Zn), iron (Fe), and manganese (Mn) concentrations at 24 h but decreased (P < 0.05) at 72 h. The intestinal gene expressions of metal transporters ZIP13, CTR1, and MT1 were significantly decreased at 24, 48, and 72 h, and DMT1 was significantly decreased at 48 h and 72 h in the infection group. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were suppressed at 48 h and 72 h, and the malondialdehyde (MDA) content was increased at 24, 48, and 72 h in the infection group; the pro-inflammatory genes including necrosis factor-α (TNF-α), lipopolysaccharide-induced TNF-α factor (LITAF), and Ras-related protein Rab6A (RAB6A) were significantly upregulated at 48 and 72 h in the infection group. These results suggest that V. parahaemolyticus infection influenced trace element homeostasis, impaired antioxidant function, and induced inflammation response in L. vannamei, which might help understand the infection mechanism. The results provide a better understanding of the L. vannamei and V. parahaemolyticus interactions and may deliver the basis for further research in preventing the bacterial diseases.

Antiviral effects of Ma Huang Tang against H1N1 influenza virus infection in vitro and in an ICR pneumonia mouse model

Ma Huang Tang (MHT), a classical Chinese herbal decoction which has been used in clinic for thousands of years, was very effective in treating the upper respiratory tract infection. But its activity against influenza virus A, the anti-inflammatory effect and the underlying mechanisms have been poorly investigated in previous researches. In this study, the antiviral efficacy of MHT directly inhibiting influenza virus A was investigated in vitro in MDCK cells. In an ICR pneumonia mouse model infected with influenza virus A PR/8/34, MHT (8, 4 and 2 g/kg) were oral administrated for 7 days after viral challenge, to evaluate the effect of MHT on ameliorating viral pneumonia and decipher the underlying mechanisms. The in vitro results showed that MHT possessed antiviral activity with low toxicity. The in vivo assays showed that MHT (8 and 4 g/kg) significantly attenuated lung histopathological changes, decreased lung index, interleukin (IL)-4,5, tumor necrosis factor alpha (TNF-α), CD3⁺, CD8⁺ T cell levels, increased IL-2, gamma interferon (IFN-γ), CD4⁺ T cell levels and CD4⁺/CD8⁺ ratio, inhibited toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and tumor necrosis factor receptor associated factor 6 (TRAF6) protein levels. All these results demonstrate that MHT can strikingly ameliorate influenza virus A pneumonia in mice, which is associated with the regulating effect of MHT in the imbalance of body's immune function and the MyD88-dependent signaling pathway of TLR4.

2'O-galloylhyperin attenuates LPS-induced acute lung injury via up-regulation antioxidation and inhibition of inflammatory responses in vivo

2'O-galloylhyperin, an active flavonol glycoside compound with remarkable anti-immune activity, was isolated from Pyrola [P. incarnata Fisch.]. However, the evidence of anti-inflammatory activity in pulmonary diseases was still not convincing. The aim of the present study was (1) to investigate the effect of 2'O-galloylhyperin on LPS-induced acute lung injury in mice, and (2) to identify the mechanisms of attenuation of inflammatory responses. The results demonstrated that 2'O-galloylhyperin significantly reduced LPS-induced inflammation damage in a dose-dependent manner. After LPS challenge, treatment with 2'O-galloylhyperin reduced the production of pro-inflammatory cytokines and chemokines, and also improved LPS-induced lung histopathology changes. 2'O-galloylhyperin also increased the activities of antioxidant enzymes, including SOD and GSH-Px to maintain cellular redox homeostasis. Furthermore, 2'O-galloylhyperin inhibited translocation of nuclear factor (NF-κB) activation and suppressed phosphorylation of MAPK signaling pathway consisting of p38, ERK, JNK. In addition, 2'O-galloylhyperin enhanced heme oxygenase-1 (HO-1) expression to block LPS-induced inflammation via activating nuclear factor-crythroid 2-related factor (Nrf2). Moreover, 2'O-galloylhyperin induced adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation. 2'O-galloylhyperin attenuated LPS-induced acute lung injury by inhibiting the MAPK and NF-κB signaling pathways, presumably related to up-regulation of the AMPK and Nrf2 signaling pathways. Furthermore, 2'O-galloylhyperin is a potential protective antioxidant to protect lung tissues from the acute injury.