摘要：
<jats:sec><jats:title>Introduction</jats:title><jats:p><jats:italic>Gelsemium elegans</jats:italic> (<jats:italic>G. elegans</jats:italic>) as a traditional medicinal plant used in livestock production. The use of <jats:italic>G. elegans</jats:italic> in veterinary clinics may pose safety risks to human health.</jats:p></jats:sec><jats:sec><jats:title>Objectives</jats:title><jats:p>The aim of this study was to investigate tissue residue depletion in pigs fed <jats:italic>G. elegans</jats:italic> powder.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>A precise quantitation method and a simultaneous semi-quantitation method for multiple components independently of standards in pig tissues were developed for the first time. The two methods were validated in terms of specificity, LODs, LOQs, linearity, accuracy, precision, and matrix effects. They were then applied to a tissue residue depletion study after <jats:italic>G. elegans</jats:italic> powder at a dose of 2% per kg feed were fed to pigs.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Compared with precise quantitation, the method validation results indicated that the semi-quantitation method was reliable and acceptable for multicomponent quantification independent of standards. Many <jats:italic>G. elegans</jats:italic> alkaloids are widely distributed in most tissues of pigs. Tissue residue depletion studies indicated that 14-hydroxygelsenicine, 11-hydroxygelsenicine, and gelsemoxonine could be used as potential residue markers, and pancreas, small intestine, and lung tissues could be considered as potential residue target tissues of <jats:italic>G. elegans</jats:italic>. In addition, both urine and plasma could be used to predict 14-hydroxygelsenicine and gelsemoxonine residues in the liver, pancreas, and small intestinal tissues of pigs.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The developed semi-quantification method can be applied to monitor the application and residue of <jats:italic>G. elegans</jats:italic>. The results provide scientific evidence for evaluating the safety of animal-derived food from <jats:italic>G. elegans</jats:italic> for consumers and will be helpful for its application and future development.</jats:p></jats:sec>
作者机构：
College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China;Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China;[Zheng, Jiaomei] Changsha Animal and Plant Disease Control Center, Changsha 410003, China;These authors equally contributed to this work.;[Long, Xueming] Hunan Provincial Institution of Veterinary Drug and Feed Control, Changsha 410006, China
通讯机构：
[Xiaojun Chen; Jiyun Li] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China
摘要：
<jats:p><jats:italic>Aeromonas hydrophila</jats:italic> is an important zoonotic pathogen responsible for septicemia, diarrhea and gastroenteritis, and has attracted considerable attention. The EnvZ/OmpR two-component system (TCS) mediates environmental stress responses in gram-negative bacteria. We investigated the role of the TCS in <jats:italic>A. hydrophila</jats:italic> by comparing the characteristics of the parental (<jats:italic>23-C-23</jats:italic>), EnvZ/OmpR knockout (<jats:italic>23-C-23:ΔEnvZ/OmpR</jats:italic>), and complemented strains (<jats:italic>23-C-23:CΔEnvZ/OmpR</jats:italic>). Under non-stress conditions, the <jats:italic>23-C-23:ΔEnvZ/OmpR</jats:italic> strain showed a significant decrease in growth rate compared to that of <jats:italic>23-C-23</jats:italic>. Transcriptome and metabonomic analysis indicated that many metabolic pathways were remarkably affected in the ΔEnvZ/OmpR strain, including the TCA cycle and arginine biosynthesis. In addition, the virulence of the ΔEnvZ/OmpR strain was attenuated in a Kunming mouse model. The ΔEnvZ/OmpR strain exhibited notably reduced tolerance to environmental stresses, including high temperature, different pH conditions, oxidative stress, and high osmotic stress. The downregulated expression of genes related to cell metabolism, motility, and virulence in the ΔEnvZ/OmpR mutant strain was further validated by real-time quantitative PCR. Consequently, our data suggest that the EnvZ/OmpR TCS is required for growth, motility, virulence, and stress response in <jats:italic>A. hydrophila</jats:italic>, which has significant implications in the development of novel antibacterial and vaccine therapies targeting EnvZ/OmpR against <jats:italic>A. hydrophila</jats:italic>.</jats:p>
期刊：
FRONTIERS IN PLANT SCIENCE,2022年13:1051756 ISSN：1664-462X
通讯作者：
Su, Y.;Xiao, L.-T.
作者机构：
[Wu, Zi-Han; Su, Yi; Wang, Ruo-Zhong; Xiao, Lang-Tao] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha, Peoples R China.;[Sun, Zhi-Liang] Hunan Agr Univ, Coll Vet Med, Changsha, Peoples R China.
通讯机构：
[Su, Y.; Xiao, L.-T.] C;College of Bioscience and Biotechnology, China
关键词：
DESI-MSI;Gelsemium elegans;alkaloid;mass spectrometry imaging;spatio-temporal distribution
摘要：
Gelsemium elegans contains multiple alkaloids with pharmacological effects, thus researchers focus on the identification and application of alkaloids extracted from G. elegans. Regretfully, the spatiotemporal distribution of alkaloids in G. elegans is still unclear. In this study, the desorption electrospray ionization mass spectrometry imaging (DESI-MSI) was applied to simultaneously analyze the distribution of pharmacologically important alkaloids in different organ/tissue sections of G. elegans at different growth stages. Finally, 23 alkaloids were visualized in roots, stems and leaves at seedling stage and 19 alkaloids were observed at mature stage. In mature G. elegans, 16 alkaloids were distributed in vascular bundle region of mature roots, 15 alkaloids were mainly located in the pith region of mature stems and 2 alkaloids were enriched in epidermis region of mature stems. A total of 16 alkaloids were detected in leaf veins of mature leaves and 17 alkaloids were detected in shoots. Interestingly, diffusion and transfer of multiple alkaloids in tissues have been observed along with the development and maturation. This study comprehensively characterized the spatial metabolomics of G. elegans alkaloids, and the spatiotemporal distribution of alkaloid synthesis. In addition, the results also have reference value for the development and application of Gelsemium elegans and other medicinal plants.
期刊：
Antimicrobial Agents and Chemotherapy,2021年65(12) ISSN：0066-4804
通讯作者：
Zhiliang Sun
作者机构：
College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan, China;Hunan Engineering Research Center of Veterinary Drugs, Changsha, Hunan, China;[Wangping Zhou; Jun Yang] Veterinary Drug Laboratory, Hunan Institute of Animal and Veterinary Science, Changsha, Hunan, China;[Junqi Liu] College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan, China<&wdkj&>Veterinary Drug Laboratory, Hunan Institute of Animal and Veterinary Science, Changsha, Hunan, China;[Gang Xiao; Zhiliang Sun] College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan, China<&wdkj&>Hunan Engineering Research Center of Veterinary Drugs, Changsha, Hunan, China
通讯机构：
[Zhiliang Sun ] C;College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan, China<&wdkj&>Hunan Engineering Research Center of Veterinary Drugs, Changsha, Hunan, China
作者机构：
[Meng-ting Zuo; Yan-chun Liu; Li Lin] College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China;Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China;[Qi Tang; Pi Cheng] Hunan Key Laboratory of Traditional Chinese Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China;[Zhi-liang Sun] College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China;[Zhao-ying Liu] College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Key Laboratory of Traditional Chinese Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
通讯机构：
[Zhao-ying Liu] C;College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Key Laboratory of Traditional Chinese Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
摘要：
The prevalence and antimicrobial susceptibility of Clostridium perfringens (C. perfringens) in chickens and pigs were investigated in Beijing and Shanxi, China. In total, 322 C. perfringens (chicken n = 60 and pig n = 262) were obtained from 620 feces of chickens (n = 256) and pigs (n = 364). Multiplex PCR for toxin typing of C. perfringens revealed that all the isolates belong to type A, with 45.7 % (147/322) isolates carrying beta-2 toxin-encoding gene cpb2. Minimum inhibitory concentrations of 27 antimicrobial agents showed that 91.0 % of the tested C. perfringens isolates were resistant to gentamicin and sulfonamides (sulfisoxazole and trimethoprimsulfamethoxazole), and little resistance was showed to amoxicillin-clavulanate, ceftiofur, doxycycline, vancomycin and linezolid. Additionally, nosiheptide, avilamycin, virginiamycin and bacitracin exhibited good activity against the tested C. perfringens with low MIC50 (0.06 to <= 4 mu g/mL) and MIC90 values (0.25-8 mu g/mL). Whole genome sequencing (WGS) of 48 representative isolates from each farm indicated that the C. perfringens contained diverse antimicrobial resistance genes [tetA(P), ant(6)-Ib, erm(Q), etc.] and toxin genes (cpb2, colA, cloSI, pfoA, etc.). By comparative analysis, four C. perfringens isolates from three different pig farms harboured cpb2-carrying plasmid pl with 100 % nucleotide sequence identity, suggesting horizontal gene transfer among these microorganisms. The further phylogenomic reconstruction, based on the core-genome single nucleotide polymorphisms (SNPs) of the representatives, demonstrating that C. perfringens from the same farms and regions were closely related. These findings expanded our knowledge of C. perfringens isolated from animals in China, which provided scientific basis for efficient intervention or prevention measures of antimicrobial resistance in animal husbandry in China.
摘要：
Simply Summary Some natural phytogenic feed additives, which contain several active compounds, have been shown to be effective alternatives to traditional antibiotics. Gelsemium elegans (G. elegans) has been used as a traditional Chinese herbal medicine for many years, and it has an obvious growth-promoting effect on animals such as pigs. To our knowledge, the internal mechanism of the influence of G. elegans on the animal body is still unclear. Here, the plasma metabolomics and liver transcriptional profile of crude extract of G. elegans in pigs were reported for the first time and the metabolic consequences of feeding piglets G. elegans for 45 days were evaluated. The results showed that the addition of 2% G. elegans powder to feed is nontoxic to pigs. In addition, G. elegans could be used as a phytogenic feed additive, which could improve the immune function of piglets, and the latent mechanism of G. elegans may be related to various signaling pathways, including the MAPK signaling pathway and PPAR signaling pathway. Collectively, results of the current provide a clearer understanding of the molecular mechanism of the pharmacological effects of G. elegans, which is of great significance for a safer and more rational application of this phytogenic feed additives. Some naturalphytogenic feed additives, which contain several active compounds, have been shown to be effective alternatives to traditional antibiotics. Gelsemium elegans (G. elegans) is a whole grass in the family Loganiaceae. It is a known toxic plant widely distributed in China and has been used as a traditional Chinese herbal medicine for many years to treat neuropathic pain, rheumatoid pain, inflammation, skin ulcers, and cancer. However, G. elegans not only is nontoxic to animals such as pigs and sheep but also has an obvious growth-promoting effect. To our knowledge, the internal mechanism of the influence of G. elegans on the animal body is still unclear. The goal of this work is to evaluate the metabolic consequences of feeding piglets G. elegans for 45 days based on the combination of transcriptomics and metabolomics. According to growth measurement and evaluation, compared with piglets fed a complete diet, adding 20 g/kg G. elegans powder to the basal diet of piglets significantly reduced the feed conversion ratio. Results of the liver transcriptome suggest that glycine and cysteine-related regulatory pathways, including the MAPK signaling pathway and the mTOR signaling pathway, were extensively altered in G. elegans-induced piglets. Plasma metabolomics identified 21 and 18 differential metabolites (p < 0.05) in the plasma of piglets in the positive and negative ion modes, respectively, between G. elegans exposure and complete diet groups. The concentrations of glycine and its derivatives and N-acetylcysteine were higher in the G. elegans exposure group than in the complete diet group.This study demonstrated that G. elegans could be an alternative to antibiotics that improves the immune function of piglets, and the latent mechanism of G. elegans may be related to various signaling pathways, including the MAPK signaling pathway and the PPAR signaling pathway.
期刊：
Journal of Veterinary Pharmacology and Therapeutics,2020年43(2):208-214 ISSN：0140-7783
通讯作者：
Liu, Zhao-Ying;Sun, Zhi-Liang
作者机构：
[Wu, Yong; Cao, Yan; Sun, Zhuo; Sun, Zhi-Liang; Liu, Zhao-Ying; Zhao, Na-Jiao; Wang, Qin] Hunan Agr Univ, Coll Vet Med, Hunan Engn Technol Res Ctr Vet Drugs, Changsha, Peoples R China.;[Liu, Zhao-Ying; Sun, ZL] Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.
通讯机构：
[Liu, ZY; Sun, ZL] H;Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.
关键词：
dihydrosanguinarine;drug metabolite;sanguinarine;unclassified drug;benzophenanthridine derivative;isoquinoline derivative;sanguinarine;animal cell;animal experiment;animal tissue;area under the curve;Article;controlled study;cytosol;drug accumulation;drug clearance;drug half life;drug metabolism;elimination half-life;female;in vitro study;in vivo study;intestine flora;intestine mucosa;maximum concentration;mean residence time;microsome;nonhuman;pharmacokinetics;priority journal;single drug dose;steady state;time to maximum plasma concentration;animal;half life time;intramuscular drug administration;metabolism;oral drug administration;pig;Administration, Oral;Animals;Area Under Curve;Benzophenanthridines;Half-Life;Injections, Intramuscular;Isoquinolines;Swine
通讯机构：
[Liu, Zhao-Ying] H;Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
摘要：
<jats:sec><jats:title>Rationale</jats:title><jats:p><jats:italic>Gelsemium elegans</jats:italic> (<jats:styled-content style="fixed-case"><jats:italic>G. elegans</jats:italic></jats:styled-content>) is highly toxic to humans and rats but has insecticidal and growth‐promoting effects on pigs and goats. However, the mechanisms behind the toxicity differences of <jats:styled-content style="fixed-case"><jats:italic>G. elegans</jats:italic></jats:styled-content> are unclear. Gelsenicine, isolated from <jats:styled-content style="fixed-case"><jats:italic>G. elegans</jats:italic>,</jats:styled-content> has been reported to be a toxic alkaloid.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>In this study, the <jats:italic>in vitro</jats:italic> metabolism of gelsenicine was investigated and compared for the first time using human (HLM), pig (PLM), goat (GLM) and rat (RLM) liver microsomes and high‐performance liquid chromatography/mass spectrometry (HPLC/MS).</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>In total, eight metabolites (<jats:bold>M1</jats:bold>–<jats:bold>M8</jats:bold>) were identified by using high‐performance liquid chromatography/quadrupole‐time‐of‐flight mass spectrometry (HPLC/QqTOF‐MS). Two main metabolic pathways were found in the liver microsomes of the four species: demethylation at the methoxy group on the indole nitrogen (<jats:bold>M1</jats:bold>) and oxidation at different positions (<jats:bold>M2</jats:bold>–<jats:bold>M8</jats:bold>). <jats:bold>M8</jats:bold> was identified only in the GLM. The degradation ratio of gelsenicine and the relative percentage of metabolites produced during metabolism were determined by high‐performance liquid chromatography/tandem mass spectrometry (HPLC/QqQ‐MS/MS). The degradation ratio of gelsenicine in liver microsomes decreased in the following order: PLM ≥ GLM > HLM > RLM. The production of <jats:bold>M1</jats:bold> decreased in the order of GLM > PLM > RLM > HLM, the production of <jats:bold>M2</jats:bold> was similar among the four species, and the production of <jats:bold>M3</jats:bold> was higher in the HLM than in the liver microsomes of the other three species.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Based on these results, demethylation was speculated to be the main gelsenicine detoxification pathway, providing vital information to better understand the metabolism and toxicity differences of <jats:styled-content style="fixed-case"><jats:italic>G. elegans</jats:italic></jats:styled-content> among different species.</jats:p></jats:sec>
