Comparison of the efficacy of Aeromonas veronii ΔhisJ vaccine in Carassius auratus via different immunization routes.

Introdction: Aeromonas veronii is a significant pathogen to various aquatic life. Infections in fish can lead to high mortality rates, causing substantial economic losses in aquaculture. Vaccination is proposed as a substitute for antibiotics in aquaculture to decrease disease-related mortality and morbidity. Our study previously constructed a hisJ-deleted strain of A. veronii, which provided protective effect to Loach. Methods: To further assess the vaccine's applicability, this study evaluated its genetic stability and safety, and the immune protective effects in Carassius auratus through four distinct administration routes: intraperitoneal injection, intramuscular injection, oral administration, and immersion, to determine the efficacy of these administration routes. Results: The results showed that the vaccine remained genetically stable after 45 generations. Immunization via these administration routes was safe for Carassius auratus, with intraperitoneal and intramuscular injections causing stronger adverse reactions. Immersion immunization resulted in mild adverse reactions, and no significant adverse reactions were observed following oral immunization. Immunizing Carassius auratus at safe concentrations via these routes enhanced the phagocytic activity in serum, increased the levels of non-specific immune-related enzymes (ACP, AKP, C3, C4, LZM, SOD, and IgM), and improved specific serum antibody levels. It also elevated levels of cytokines related to inflammatory responses (IL-1ß, IL-10, TNF-α, TGF-ß) in organ tissues (liver, spleen, kidney, mid-post intestine, and gills). The survival rates of Carassius auratus were measured after challenging with the virulent strain A. veronii TH0426, resulting in the relative survival rates of 64% for Intraperitoneal vaccine group, 56% for Intramuscular vaccine group, 52% for oral vaccine group, and 48% for immersion vaccine group. Analysis of bacterial load in the liver, spleen, and kidney post-challenge showed a decreasing trend in the control group, indicating that the vaccine strain ΔhisJ could gradually restrict the rapid proliferation of bacteria in these tissues, thereby providing a certain level of immune protection against A. veronii. Discussion: In brief, the vaccine strain ΔhisJ can serve as a safe live attenuated vaccine for Carassius auratus, and this study lays the foundation for the development of live attenuated vaccines against Aeromonas veronii.

CheV enhances the virulence of Salmonella Enteritidis, and the Chev-deleted Salmonella vaccine provides immunity in mice.

BACKGROUND: Salmonella enteritidis (SE) is a major zoonotic pathogen and causes infections in a variety of hosts. The development of novel vaccines for SE is necessary to eradicate this pathogen. Genetically engineered attenuated live vaccines are more immunogenic and safer. Thus, to develop a live attenuated Salmonella vaccine, we constructed a cheV gene deletion strain of SE (named ΔcheV) and investigated the role of cheV in the virulence of SE. First, the ability to resist environmental stress in vitro, biofilm formation capacity, drug resistance and motility of ΔcheV were analyzed. Secondly, the bacterial adhesion, invasion, intracellular survival assays were performed by cell model. Using a mouse infection model, an in vivo virulence assessment was conducted. To further evaluate the mechanisms implicated by the reduced virulence, qPCR analysis was utilized to examine the expression of the strain's major virulence genes. Finally, the immune protection rate of ΔcheV was evaluated using a mouse model. RESULTS: Compared to C50336, the ΔcheV had significantly reduced survival ability under acidic, alkaline and thermal stress conditions, but there was no significant difference in survival under oxidative stress conditions. There was also no significant change in biofilm formation ability, drug resistance and motility. It was found that the adhesion ability of ΔcheV to Caco-2 cells remained unchanged, but the invasion ability and survival rate in RAW264.7 cells were significantly reduced. The challenge assay results showed that the LD50 values of C50336 and ΔcheV were 6.3 × 105 CFU and 1.25 × 107 CFU, respectively. After the deletion of the cheV gene, the expression levels of fimD, flgG, csgA, csgD, hflK, lrp, sipA, sipB, pipB, invH, mgtC, sodC, rfbH, xthA and mrr1 genes were significantly reduced. The live attenuated ΔcheV provided 100% protection in mice against SE infection. CONCLUSION: All the results confirmed that the deletion of the cheV gene reduces the virulence of SE and provides significant immune protection in mice, indicating that ΔcheV could be potential candidates to be explored as live-attenuated vaccines.

Research Note: Antibiotic resistance and pathogenicity of geese-derived Riemerella anatipestifer isolated from eastern regions of Hebei Province, China.

Riemerella anatipestifer (R. anatipestifer) can cause serositis in multiple poultry species, resulting in significant losses. Although R. anatipestifer-caused infections in ducks have been well established, the literature about this disease in geese is rare. Here, we isolated and identified 56 strains of R. anatipestifer from the eastern regions of Hebei Province, China, and further determined their serotypes, antibiotic resistance, and pathogenicity. A total of 75 strains of causative bacteria were isolated from 70 sick geese with serositis. After Gram staining microscopy, PCR, and 16S rDNA sequence analysis, 56 isolates were identified as members of R. anatipestifer and 19 as Escherichia coli (E. coli). The results of serotyping showed that there were 4 serotypes prevalent in the isolate, including serotype 1 (37/56), serotype 2 (9/56), serotype 11 (8/56), and serotype 13 (2/56). The results of antibiotic susceptibility testing revealed that all 56 R. anatipestifer isolates showed varying degrees of multidrug resistance (MDR). A total of 10 antibiotic resistance genes (ARG) were determined in these isolates. Four isolates of different serotypes were selected for pathogenicity examination, and all were able to reproduce serositis-like symptoms in 15-day-old goslings, with neurological symptoms and a 100% mortality rate. Hemorrhagic congestion of the brain tissue, steatosis of the hepatocytes, and disorganization of some cardiac myofibers were observed in R. anatipestifer-infected geese. All these findings will contribute to our insights into the prevalence characteristics, antibiotic resistance profile, and pathogenicity of R. anatipestifer infection in geese in eastern Hebei Province and provide scientific guidance for the treatment and control of this disease.

Digital economy and carbon emission: The coupling effects of the economy in Qinghai region of China.

This study provides an in-depth analysis of the complex relationship between the digital economy and carbon emissions, fully drawing on essential principles of environmental economics, coupled economics, and sustainable development theory. Focusing on the Qinghai region in the western province of China, the study employs highly sophisticated methods such as multiple regression analysis and system dynamics modeling to reveal the multidimensional coupling effects between digital economy development and carbon emission dynamics. The study's results clearly show that in the Qinghai region of China, the booming growth of the digital economy is related to carbon emissions. Of particular interest, the study finds that this relationship exhibits a high degree of complexity and non-linearity and evolves gradually over time. Initially, the rapid expansion of the digital economy, accompanied by high energy consumption and increased carbon emissions, posed a significant challenge to environmental protection. However, a clear inverted "U"-shaped relationship has emerged as the digital economy evolves. This key inflection point signals a shift in the landscape as the digital economy begins to deliver some ecological benefits, potentially reducing the trend of carbon emissions in the future. The findings of this study go beyond simple causality and reveal a complex and evolving dynamic relationship between the digital economy and carbon emissions. Through such insights, this study provides a solid academic foundation and carefully constructs actionable policy recommendations to drive sustainable development. These insights apply to the Qinghai region of China and provide valuable references and lessons for other areas facing similar challenges.

What determines the performance of low-carbon cities in China? Analysis of the grouping based on the technology-Organization-Environment framework.

BACKGROUND AND OBJECTIVES: Addressing climate change and reducing greenhouse gas emissions have emerged as shared global objectives. Enhancing the development performance of low-carbon cities has become an urgent and widely acknowledged concern for both government policy-making departments and academics. Drawing upon the complex grouping perspective and resource allocation theory, this study investigates how varying conditions related to technology, organization, and environment in Chinese low-carbon pilot cities can effectively allocate resources to shape the governance performance of low-carbon cities. METHODS AND DATA: This paper employs a comprehensive grouping analysis perspective, treating the research object as a combination of various ways between condition variables. It integrates the advantages of case studies and variable studies, and investigates the collective relationships between elemental groupings and outcomes using the fsQCA analysis method. This approach facilitates the understanding of multiple concurrent causal relationships within the technology-organization-environment (TOE) framework, accounting for different performance levels in Chinese low-carbon pilot cities, as well as addressing complex causal issues such as asymmetry and multiple scenario equivalence. Data from 30 representative low-carbon pilot cities in China were employed to validate the TOE theoretical framework. CONCLUSION: No single element alone can be considered a necessary condition for low-carbon city governance performance. However, environmental enhancement plays a more prominent role in the governance performance of low-carbon cities. Additionally, the presence of "multiple concurrent" technical, organizational, and environmental conditions leads to a diverse range of governance performance in Chinese low-carbon pilot cities. In other words, the driving paths of low-carbon city performance exhibit distinct pathways. CONTRIBUTION: The findings of this study can assist low-carbon pilot city managers in generating effective governance ideas, facilitating the successful implementation of low-carbon city pilot projects, and drawing valuable lessons from the experience of low-carbon city development in China.

Pal Affects the Proliferation in Macrophages and Virulence of Brucella, and as Mucosal Adjuvants, Provides an Effective Protection to Mice Against Salmonella Enteritidis.

The purpose of this study was to elucidate the roles of peptidoglycan-associated lipoprotein (Pal protein) in the proliferation of Brucella in macrophage and bacterial virulence, and to evaluate the immune effect of Pal protein to Salmonella enteritidis. Murine macrophage-like cell line Raw264.7 was stimulated by recombinant Pal protein, and the expression of TNF-α and IFN-γ were up-regulated, but not it of IL-1ß and IL-6. The macrophages infection and in vitro simulated stress assays showed that deletion of pal gene reduced the proliferation of Brucella in macrophages, the survival in acidic, oxidative and polymyxin B-contained environment. The mice infection assay showed that mice challenged with the pal mutant strain were found to have more severe splenomegaly, but less bacterial load. After oral immunization of mice, Pal protein induced a higher titer of mucosal and humoral antibody (IgA and IgG) against heat-killed Salmonella enteritidis, and a stronger Th1 cellular immune response. The challengte experiments showed Pal protein elevated the survival rate and reduced the bacterial load of spleens in immunized mice. In conclusion, our results revealed the important roles of pal gene in Brucella virulence, and Pal protein was a potentially valuable adjuvant against mucosal pathogens, such as Salmonella enteritidis.

Albiflorin ameliorates inflammation and oxidative stress by regulating the NF-κB/NLRP3 pathway in Methotrexate-induced enteritis.

Methotrexate (MTX) treats various diseases but also damages intestinal barrier and leads to enteritis. Albiflorin (ALB) has a variety of pharmacological effects, including antioxidant, anti-inflammation and anti-apoptosis. In the present study, we evaluated the therapeutic effect of ALB on MTX-induced enteritis and investigated the possible mechanisms involved. Male SD rats were intraperitoneally injected with 7 mg/kg MTX for three consecutive days to establish the enteritis model. ALB (20 or 40 mg/kg/day) was intragastrically administrated since two days prior MTX treatment and lasted for six days. We found that ALB treatment increased body weight and intestinal weight of rats with MTX injection. The disease activity index (DAI) score was also decreased after ALB administration. In histological examination, ALB treatment attenuated inflammatory cells infiltration and promoted survival of goblet cells. In detection of inflammatory-associated factors, ALB treatment decreased CD68+ cells infiltration, inhibited myeloperoxidase activity, and suppressed intercellular cell adhesion molecule-1 and cyclooxygenase-2 expression. Additionally, ALB reduced malondialdehyde, glutathione levels, inhibited superoxide dismutase activity and suppressed reactive oxygen species production. Moreover, ALB treatment effectively inhibited NLRP3, as well as caspase 1 p20 and interleukin (IL)-1ß and 18 expression. Finally, nuclear factor-κB (NF-κB) p65 phosphorylation and nuclear translocation were also demonstrated to be blocked upon ALB treatment. In conclusion, our findings indicated that ALB alleviated MTX-induced enteritis via inhibiting the NF-κB/NLRP3 pathway.

Procyanidin A1 alleviates DSS-induced ulcerative colitis via regulating AMPK/mTOR/p70S6K-mediated autophagy

Ulcerative colitis (UC) is a recurrent chronic inflammatory disease. The symptom of UC is mainly diarrhea including bloody stools. Increasing evidence has suggested that procyanidin A1 (PCA1) exerts an anti-inflammatory effect in several diseases. However, the role of PCA1 in UC is still a mystery. In our study, we explored the effect of PCA1 in dextran sulfate sodium (DSS)–induced UC mice and lipopolysaccharide (LPS)-stimulated HT-29 and IEC-6 cells. Then, cell proliferation, apoptosis, the production of proinflammatory cytokines, and autophagy-related markers were determined. Furthermore, the AMPK/mTOR/p70S6K signaling pathway was assayed by Western blot assay. In in vivo study, we found that PCA1 administration alleviated DSS-induced UC, as evidenced by reducing weight loss, clinical scores, colon weight/length ratio, histological damage, proinflammatory cytokines, and apoptosis. Moreover, we showed that the expression of Beclin-1 and LC3II/I ratio was increased, whereas the level of p62 was decreased after PCA1 treatment in vivo. Meanwhile, the reduced AMP/ATP ratio, enhanced expression of p-AMPK, and decreased p-p70S6K and p-mTOR levels indicate the activation of AMPK/mTOR/p70S6K signaling pathway. In in vitro study, PCA1 promoted cell proliferation and inhibited cell apoptosis in LPS-stimulated HT-29 and IEC-6 cells. Pro-inflammatory cytokines and autophagy-related factors exhibited the same trend as in in vivo results. Mechanically, PCA1 activated the AMPK/mTOR/p70S6K signaling pathway. The treatment with an AMPK inhibitor compound C significantly reversed the anti-inflammatory effect of PCA1 in LPS-stimulated cells. Taken together, these data indicated that PCA1 alleviated UC through induction of AMPK/mTOR/p70S6K-mediated autophagy. (AU)

Procyanidin A1 alleviates DSS-induced ulcerative colitis via regulating AMPK/mTOR/p70S6K-mediated autophagy.

Ulcerative colitis (UC) is a recurrent chronic inflammatory disease. The symptom of UC is mainly diarrhea including bloody stools. Increasing evidence has suggested that procyanidin A1 (PCA1) exerts an anti-inflammatory effect in several diseases. However, the role of PCA1 in UC is still a mystery. In our study, we explored the effect of PCA1 in dextran sulfate sodium (DSS)-induced UC mice and lipopolysaccharide (LPS)-stimulated HT-29 and IEC-6 cells. Then, cell proliferation, apoptosis, the production of proinflammatory cytokines, and autophagy-related markers were determined. Furthermore, the AMPK/mTOR/p70S6K signaling pathway was assayed by Western blot assay. In in vivo study, we found that PCA1 administration alleviated DSS-induced UC, as evidenced by reducing weight loss, clinical scores, colon weight/length ratio, histological damage, proinflammatory cytokines, and apoptosis. Moreover, we showed that the expression of Beclin-1 and LC3II/I ratio was increased, whereas the level of p62 was decreased after PCA1 treatment in vivo. Meanwhile, the reduced AMP/ATP ratio, enhanced expression of p-AMPK, and decreased p-p70S6K and p-mTOR levels indicate the activation of AMPK/mTOR/p70S6K signaling pathway. In in vitro study, PCA1 promoted cell proliferation and inhibited cell apoptosis in LPS-stimulated HT-29 and IEC-6 cells. Pro-inflammatory cytokines and autophagy-related factors exhibited the same trend as in in vivo results. Mechanically, PCA1 activated the AMPK/mTOR/p70S6K signaling pathway. The treatment with an AMPK inhibitor compound C significantly reversed the anti-inflammatory effect of PCA1 in LPS-stimulated cells. Taken together, these data indicated that PCA1 alleviated UC through induction of AMPK/mTOR/p70S6K-mediated autophagy.

The efficacy and safety of fire needle for cervical spondylotic radiculopathy: A protocol for systematic review and meta-analysis.

BACKGROUND: Cervical spondylotic radiculopathy (CSR) is one of the most common types of cervical spondylosis, and its treatments are mainly for relieving radicular pain and improving dysfunction. The existing randomized controlled trials (RCTs) suggest that fire needle may be a potential therapy in the treatment of CSR, but there is no evidence-based medical evidence to date. Therefore, this study will systematically evaluate the efficacy and safety of fire needle in the treatment of CSR. METHODS: We will search for 7 electronic databases (PubMed, EMBASE, Cochrane library, China National Knowledge Infrastructure, Chinese Scientific Journals Database, Sinomed, and Wanfang Database) and 2 trial registration platforms (ClinicalTrials.gov and Chinese Clinic Trials.gov) to collect eligible studies. The RCTs related to fire needle for CSR and published up to June 30, 2021 will be included, regardless of language. We will consider the visual analogue scale as the primary outcome and the secondary outcome will include cervical range of motion, assessment of muscle strength, neck disability index, the MOS item short from health survey, activities of daily living, total efficiency, and adverse reactions. We will use the standard proposed in Cochrane Handbook 5.1.0 to assess the quality and bias risk of every RCT, and all analyses will be conducted through RevMan software V5.3 (Copenhagen: Nordic Cochrane Center, Cochrane, Collaborative Organization, 2014). RESULTS: This systematic review and meta-analysis will provide a convincing synthesis of existing evidences on the efficacy and safety of fire needle for CSR, and the results will be submitted to a peer-reviewed journal for publication. CONCLUSION: The results of this study will provide high-quality evidence of fire needle in the treatment of CSR for clinical decision-making. INPLASY REGISTRATION NUMBER: INPLASY202170041.

Effect of Vitamin A Supplementation on Growth Performance, Serum Biochemical Parameters, Intestinal Immunity Response and Gut Microbiota in American Mink (Neovison vison).

This experiment investigated the effect of vitamin A supplementation on growth, serum biochemical parameters, jejunum morphology and the microbial community in male growing-furring mink. Thirty healthy male mink were randomly assigned to three treatment groups, with 10 mink per group. Each mink was housed in an individual cage. The mink in the three groups were fed diets supplemented with vitamin A acetate at dosages of 0 (CON), 20,000 (LVitA) and 1,280,000 IU/kg (HVitA) of basal diet. A 7-day pretest period preceded a formal test period of 45 days. The results show that 20,000 IU/kg vitamin A increased the ADG, serum T-AOC and GSH-Px activities, villus height and villus height/crypt depth ratio (p < 0.05). The mRNA expression levels of IL-22, Occludin and ZO-1 in the jejunum of mink were significantly higher in the LVitA group than those in the CON and HVitA groups (p < 0.05). Vitamin A supplementation increased the diversity of jejunum bacteria, decreased the ratio of Firmicutes to Bacteroidetes and increased the relative abundance of Akkermansia, uncultured bacterium f Muribaculaceae, Allobaculum, Lachnospiraceae NK4A136 group, Rummeliibacillus and Parasutterella. The comparison of potential functions also showed enrichment of glycan biosynthesis and metabolism, transport and catabolism pathways in the vitamin A supplementation groups compared with the CON group. In conclusion, these results indicate that dietary vitamin A supplementation could mediate host growth by improving intestinal development, immunity and the relative abundance of the intestinal microbiota.

Immunosuppressive gentianellane-type sesterterpenoids from the traditional Uighur medicine Gentianella turkestanorum.

Whole plants of Gentianella turkestanorum are commonly used as a traditional Uighur medicine. A phytochemical investigation led to the isolation of eight undescribed gentianellane-type sesterterpenoids (18-epi-nitidasin, gentianelloids D-F, and 18-epi-gentianelloids C-F), one undescribed 11,12-seco-gentianellane (18-epi-alborosin), and three known analogs (nitidasin, gentianelloid C and alborosin) among which gentianelloid C was found for the first time from a natural source. The structures of these compounds were elucidated by extensive spectroscopic analyses (including 1D and 2D NMR, HRMS, IR, and specific rotation) and in the case of 18-epi-gentianelloid C by the single-crystal X-ray diffraction analysis. A putative biosynthetic route for these sesterterpenoids was proposed. The immunosuppressive activity of the isolated compounds was also evaluated by their ability to inhibit the proliferation of T cells and T cell cytokine IFN-γ production. Nitidasin suppressed IFN-γ production with an IC50 value of 16.50 µM, while gentianelloid F and alborosin inhibited the proliferation of and IFN-γ production in T cells with IC50 values of 12.40-14.66 µM.

Strictosamide alleviates the inflammation in an acute ulcerative colitis (UC) model.

The ulcerative colitis (UC) is a typical inflammatory bowel disease (IBD) causing great damages, while strictosamide (STR) is a natural alkaloid that possesses strong anti-inflammatory property in infection and inflammation-related diseases. Our study is aimed at evaluating the anti-inflammatory activity of STR in the course of UC. Briefly, male Balb/c mice were treated with 3.5% dextran sulfate sodium (DSS) for 6 consecutive days to establish an acute model of UC, and the administration of gradient concentrations of STR was subsequently performed. Accordingly, colonic pathological alterations including the reduced ratio of colon weight/length, decreased disease activity index (DAI), and attenuated H&E damage were found in UC mice after STR treatment. Based on the analyses of real-time PCR and western blot, downregulation of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) was also determined in the colonic tissue of UC mice after the treatment of STR. ELISA and immunohistochemical staining further suggest the relief of inflammation in UC mice with decreased expressions of MPO and iNOS after STR treatment. In addition, STR was also validated to significantly inhibit NF-κB signaling in UC mice by western blot and Electrophoretic Mobility Shift Assay (EMSA). Meanwhile, restricted inflammation was also determined in STR-treated IEC6 and HT-29 cells. The utilization of PDTC, an inhibitor of NF-κB, further demonstrated that STR ameliorated the inflammation by inhibiting the NF-κB signaling in vitro. In summary, our study suggests that STR could be a potential candidate for IBD therapy.

Echinacea polysaccharide attenuates lipopolysaccharide­induced acute kidney injury via inhibiting inflammation, oxidative stress and the MAPK signaling pathway.

Acute kidney injury (AKI) is often accompanied by inflammation. Echinacea polysaccharide (EP) is an active ingredient that has been demonstrated to possess anti­oxidative, anti­inflammatory, antimicrobial and immunomodulatory functions. However, the role of EP in AKI has not been examined. The present study investigated the effects of EP on lipopolysaccharide (LPS)­induced AKI. Western blotting, immunohistochemistry and immunofluorescence analyses were performed to detect protein expression levels. Administration of EP significantly attenuated LPS­induced renal tissue injury, along with a decrease in blood urea nitrogen and creatinine levels. EP decreased the levels of inducible nitric oxide synthase and cyclo­oxygenase­2 in LPS­treated mice. Furthermore, LPS­induced inflammation was inhibited by EP in renal tissues and HBZY­1 cells, as demonstrated by the downregulation of tumor necrosis factor­α, interleukin (IL)­1ß, IL­6, nitric oxide and prostaglandin E2 levels. Similarly, EP administration decreased oxidative stress (OS) via decreasing reactive oxygen species, malondialdehyde and oxidized glutathione levels, and increasing superoxide dismutase, catalase, glutathione reductase and reduced glutathione activity. Notably, EP induced a marked decrease in the expression levels of phospho­extracellular signal­regulated protein kinase (p­ERK), phospho­c­Jun N­terminal kinase (p­JNK) and p­p38 in vivo and in vitro. In addition, in LPS­treated HBZY­1 cells, EP enhanced cell viability and inhibited nuclear translocation of p­ERK, p­JNK and p­p38. Overall, the present findings demonstrated that EP alleviated LPS­induced AKI via the suppression of inflammation, OS and the mitogen­activated protein kinase signaling pathway, providing insight into potential avenues for the treatment of AKI.

Echinacea polysaccharide alleviates LPS-induced lung injury via inhibiting inflammation, apoptosis and activation of the TLR4/NF-κB signal pathway.

Lung injury is a common critical life-threatening syndrome. Inflammation is a key factor in the pathogenesis of lung injury. It is reported that Echinacea Polysaccharides (EP) has anti-inflammatory activity. However, the effect of EP on lung injury remains unclear. In our study, murine model of lung injury was induced with 2.5 mg/kg LPS before administration of 5 mg/kg or 10 mg/kg EP. EP ameliorated LPS-induced lung pathological damage, along with reduction in lung wet/dry weight ratio and myeloperoxidase activity. EP decreased the number of leukocytes, eosinophils, neutrophils, lymphocytes and macrophages in bronchoalveolar lavage fluid, and the release of tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) in LPS-treated lung. EP suppressed LPS-induced apoptosis along with down-regulation of Bcl2-associated X (Bax) and cleaved caspase-3 (CC3), and elevated B-cell lymphoma-2 (Bcl-2). Besides, RAW 264.7 cells were treated with EP 100 µg/ml for 1 h and then incubated with 1 µg/ml LPS for 24 h. TNF-α, IL-6 and IL-1ß levels were lowered by treatment of EP in LPS-treated RAW 264.7 cells. Moreover, EP down-regulated the expression of toll-like receptor 4 (TLR4), myeloid differentiating factor 88 (MyD88), p-IκBα, nuclear factor kappa-B (NF-κB), p-NF-κB, and up-regulated the inhibitor of NF-κB (IκBα) in vivo and in vitro following LPS induction, which is consistent with the effect of TAK-242. In conclusion, EP may alleviate LPS-induced lung injury via inhibiting inflammation, apoptosis and activation of TLR4/NF-κB signal pathway.

Nucleoside Diphosphate Kinases (ndk) reveals a key role in adhesion and virulence of Aeromonas veronii.

Aeromous veronii is a severe pathogen that can infect aquatic organisms and mammals also causes irreparable damage to fish aquaculture. Analysis of the results of epidemiological investigations have revealed that its tolerance to drugs and the virulence of A. veronii have increased in recent years. Most of the researches on A. veronii focuse on the strain isolation, identification, and drug susceptibility. However, we do not know so much about the molecular mechanism of the pathogenesis on A. veronii. Here we identified and obtained the highly expressed TH0426 Nucleoside Diphosphate Kinases (NDK) of A. veronii. We first constructed a mutant strain (△-ndk) by generating an in-frame deletion of the ndk gene, to investigate the functional role in A. veronii TH0426. The ability in the adhesion and invasion of EPC cells and biofilm formation significantly reduced of the △-ndk strain. The motility test showed that the ndk gene affected on the swimming ability, while did not affect the swarming motility. Compared with the wild-type strain TH0426, the pathogenicity of △-ndk strain to zebrafish reduced severely. Besides, the ndk gene has affected the apoptosis rate of A. veronii TH0426. These results would help to demonstrate the function of ndk further and realize the pathogenesis on A. veronii.

Molecular characteristics of the capsid protein VP2 gene of canine parvovirus type 2 amplified from raccoon dogs in Hebei province, China.

Canine parvovirus type 2 (CPV-2) is currently circulating in domestic and wild animals, but our knowledge about CPV-2 infections in raccoon dogs is limited. In this study, VP2 gene sequences of CPV-2 were amplified from rectal swabs of 14 diarrhetic raccoon dogs (Nyctereutes procyonoides) in Hebei province, China, in 2016 and 2017. Phylogenetic analysis of the VP2 gene sequences revealed that most of these sequences (11 of 14) belonged to the same subclade as raccoon dog strain CPV-2/Raccoon_Dog/China/DP-1/16 isolated from Shandong province in 2016. A comparison of deduced amino acid sequences revealed presence of the substitutions S297A and S27T in 11 of those 14 sequences. I418T was observed in a minority of the sequences (4 of 14). In addition, A300D and T301I, P13S and I219V, and N419K were found in three of the sequences. This study shows that CPV-2 strains with different substitutions in their VP2 amino acid sequences were spreading among raccoon dogs in Hebei during 2016 and 2017 and suggests that further studies are needed to monitor the distribution of these strains in China.

Gentianelloids A and B: Immunosuppressive 10,11-seco-Gentianellane Sesterterpenoids from the Traditional Uighur Medicine Gentianella turkestanorum.

Two sesterterpenoids, possessing an unusual 10,11-seco-gentianellane skeleton, gentianelloids A and B, were isolated from a traditional Uighur medicine Gentianella turkestanorum. Through extensive spectroscopic analysis and single-crystal X-ray diffraction, their structures including absolute configurations were unambiguously determined. A plausible biosynthetic pathway for the two compounds was proposed. Both compounds showed remarkable immunosuppressive activity, including inhibition of the proliferation, activation, and cytokine IFN-γ production of T cells. The findings suggested that sesterterpenoids could contribute positively to the therapeutic effects of this popular traditional Uighur medicine.

Cadaverine reverse transporter (CadB protein) contributes to the virulence of Aeromonas veronii TH0426.

Aeromonas veronii is one of the main pathogens causing sepsis and ulcer syndrome in freshwater fish. Analysis of the results of epidemiological investigations in recent years has revealed that the virulence of A. veronii and its tolerance to drugs have been increasing year by year. Currently, most of the research on A. veronii focuses on its isolation, identification, and drug susceptibility, whereas research on its virulence factors and pathogenesis mechanisms is relatively rare. In this study, we identified and obtained the highly expressed TH0426 cadaverine reverse transporter (CadB) of A. veronii. We used efficient suicide plasmid-mediated homologous recombination to delete the cadB gene in TH0426 and constructed a cadB deletion strain. The LD50 of ΔcadB was 93.2 times higher than that of TH0426 in zebrafish, the toxicity of ΔcadB was 9.5 times less than that of TH0426 in EPC cells, and the biofilm formation ability of ΔcadB was 5.6-fold greater than that of TH0426. In addition, motility detection results indicated that ΔcadB had lost its swimming ability. The results of flagellar staining and TEM demonstrated that ΔcadB shed the flagella. In summary, the virulence and adhesion of A. veronii TH0426 were significantly decreased by the deletion of cadB, which might provide a theoretical basis for research into A. veronii virulence factors.

Syringin protects against colitis by ameliorating inflammation.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition with high incidence. Syringin exhibits multiple pharmacological properties, including anti-inflammatory effects. However, the effect of syringin on inflammation of IBD is still unclear. Here, the dextran sulfate sodium (DSS)-induced colitis model was established in vivo. Rat intestinal epithelium IEC6 cells were treated with lipopolysaccharide (LPS) in vitro. Syringin inhibited DSS or LPS-induced overproduction of proinflammatory cytokines (IL-1ß, IL-6, TNF-α) and proinflammatory substances (iNOS, COX-2). Moreover, syringin inactivated the proinflammatory NF-κB p65 pathway by decreasing IκBα phosphorylation at Ser 32. The activation of antioxidant Nrf2 signaling pathway was promoted by syringin. Additionally, LPS-induced inflammation in IEC6 cells was also suppressed by NF-κB inhibitor PDTC and Nrf2 activator RTA408. The anti-inflammatory effects of syringin were comparable to these two reagents. Taken together, our results suggest that syringin shows protective effects on intestinal inflammation through inhibiting NF-κB, while activating Nrf2 signaling pathway in colitis.