Endo-beta-N-acetylglucosaminidase (ENGase) is widely distributed in various organisms. The first reported ENGase activity was detected in Diplococcus pneumoniae in 1971. The protein (Endo D) was purified and its peptide sequence was determined in 1974. Three ENGases (Endo F1-F3) were discovered in Flavobacterium meningosepticum from 1982 to 1993. After that, the activity was detected from different species of bacteria, yeast, fungal, plant, mice, human, etc. Multiple ENGases were detected in some species, such as Arabidopsis thaliana and Trichoderma atroviride. The first preliminary crystallographic analysis of ENGase was conducted in 1994. But to date, only a few ENGases structures have been obtained, and the structure of human ENGase is still missing. The currently identified ENGases were distributed in the GH18 or GH85 families in Carbohydrate-Active enZyme (CAZy) database. GH18 ENGase only has hydrolytic activity, but GH85 ENGase has both hydrolytic and transglycosylation activity. Although ENGases of the two families have similar (β/α)8-TIM barrel structures, the active sites are slightly different. ENGase is an effective tool for glycan detection andglycan editing. Biochemically, ENGase can specifically hydrolyze β‑1,4 glycosidic bond between the twoN-acetylglucosamines (GlcNAc) on core pentasaccharide presented on glycopeptides and/or glycoproteins. Different ENGases may have different substrate specificity. The hydrolysis products are oligosaccharide chains and a GlcNAc or glycopeptides or glycoproteins with a GlcNAc. Conditionally, it can use the two products to produce a new glycopeptides or glycoprotein. Although ENGase is a common presentation in cell, its biological function remains unclear. Accumulated evidences demonstrated that ENGase is a none essential gene for living and a key regulator for differentiation. No ENGase gene was detected in the genomes of Saccharomyces cerevisiae and three other yeast species. Its expression was extremely low in lung. As glycoproteins are not produced by prokaryotic cells, a role for nutrition and/or microbial-host interaction was predicted for bacterium produced enzymes. In the embryonic lethality phenotype of the Ngly1-deficient mice can be partially rescued by Engase knockout, suggesting down regulation of Engase might be a solution for stress induced adaptation. Potential impacts of ENGase regulation on health and disease were presented. Rabeprazole, a drug used for stomach pain as a proton inhibitor, was identified as an inhibitor for ENGase. ENGases have been applied in vitro to produce antibodies with a designated glycan. The two step reactions were achieved by a pair of ENGase dominated for hydrolysis of substrate glycoprotein and synthesis of new glycoprotein with a free glycan of designed structure, respectively. In addition, ENGase was also been used in cell surface glycan editing. New application scenarios and new detection methods for glycobiological engineering are quickly opened up by the two functions of ENGase, especially in antibody remodeling and antibody drug conjugates. The discovery, distribution, structure property, enzymatic characteristics and recent researches in topical model organisms of ENGase were reviewed in this paper. Possible biological functions and mechanisms of ENGase, including differentiation, digestion of glycoproteins for nutrition and stress responding were hypothesised. In addition, the role of ENGase in glycan editing and synthetic biology was discussed. We hope this paper may provide insights for ENGase research and lay a solid foundation for applied and translational glycomics.

Protein as the allergens could lead to allergy. In addition, a widespread class of allergens were known as glycans of N-glycoprotein. N-glycoprotein contained oligosaccharide linked by covalent bonds with protein. Recently,studies implicated that allergy was associated with glycans of heterologous N-glycoprotein found in food, inhalants, insect toxins, etc. The N-glycan structure of N-glycoprotein allergen has exerted an influence on the binding between allergens and IgE, while the recognition and presentation of allergens by antigen-presenting cells (APCs) were also affected. Some researches showed thatN-glycan structure of allergen was remodeled by N-glycosidase, such as cFase I, gpcXylase, as binding of allergen and IgE partly decreased. Thus, allergic problems caused by N-glycoproteins could potentially be solved by modifying or altering the structure ofN-glycoprotein allergens, addressing the root of the issue. Mechanism of N-glycans associated allergy could also be elaborated through glycosylation enzymes, alterations of host glycosylation. This article hopes to provide a separate insight for glycoimmunology perspective, and an alternative strategy for clinical prevention or therapy of allergic diseases.

ObjectiveThe purpose of this study was to investigate the effects of transcutaneous electrical acupoint stimulation (TEAS) on cognitive function of vascular dementia (VD) rats and its mechanism. MethodsVD rat model was established by modified two-vessel occlusion (2-VO). After modeling, TEAS and electroacupuncture (EA) were used to stimulate Baihui and Zusanli points of rats respectively for 14 d. After treatment, novel object recognition test, Morris water maze test, and Y maze test were used to evaluate the spatial memory and learning ability of rats. Hematoxylin and eosin staining was used to observe the morphology of hippocampal neurons. Transmission electron microscopy was used to observe the ultrastructure of hippocampal mitochondria. Enzyme-linked immunosorbent assay kits were used to detected the levels of SOD, CAT, GSH-Px, MDA and ROS in serum of rats. Western blot was used to detect the expression of PGC-1α, TFAM, HO-1, NQO1 proteins in the hippocampus, Keap1 protein in the cytoplasm and Nrf2, NRF1 proteins in the nucleus. ResultsAfter treatment for 14 d, compared to the model group, the escape latency of VD rats decreased, while the discrimination index, the times of rats crossing the original platform area, the residence time in the original platform quadrant, and the percentage of alternation increased. TEAS can improve the structure of hippocampal neurons and mitochondria of VD rats, showing that neurons were arranged more regularly and distributed more evenly, nuclear membrane and nucleoli were clearer, and mitochondrial swelling were reduced, mitochondrial matrix density were increased, and mitochondrial cristae were more obvious. The levels of SOD, GSH-Px and CAT in serum increased significantly, while the concentration of MDA and ROS decreased. TEAS also up-regulated the expression levels of PGC-1α TFAM, NQO1 and HO-1 proteins in the hippocampus and Nrf2, NRF1 proteins in the nucleus, but down-regulated the Keap1 protein in the cytoplasm. ConclusionTEAS can improve cognition, hippocampal neurons and mitochondrial structure of VD rats, and the effect is better than EA. The mechanism may be the activation of PGC-1α mediated mitochondrial biogenesis and antioxidant stress, which also provides a potential therapeutic technology and experimental basis for the treatment of VD.

The emerging and re-emerging arthropod-borne infectious diseases pose a serious threat to global public health security. Field and laboratory studies of arthropods of medical importance are essential and critical for the prevention and control of arthropod-borne infectious diseases. Various institutions or universities in China have been conducting research in the field or laboratory study of arthropods of medical importance, but up to 2023, it is still lacking detailed biosafety guidelines or recommendations that can guide the related work for arthropods of medical importance. In order to proactively address potential biosafety issues in the field or laboratory activities related to arthropods of medical importance, improve the standardization of arthropod biosafety classification, operations, and protection, and ensure the safety of practitioners, an expert consensus on the biosafety recommendation of arthropods of medical importance in field and laboratory has been developed, aiming to guide the future work of arthropods and ensure the national biosafety and biosecurity of China.

Objective This study aimed to investigate the potential relationship between urinary metals copper (Cu), arsenic (As), strontium (Sr), barium (Ba), iron (Fe), lead (Pb) and manganese (Mn) and grip strength. Methods We used linear regression models, quantile g-computation and Bayesian kernel machine regression (BKMR) to assess the relationship between metals and grip strength.Results In the multimetal linear regression, Cu (β=-2.119), As (β=-1.318), Sr (β=-2.480), Ba (β=0.781), Fe (β= 1.130) and Mn (β=-0.404) were significantly correlated with grip strength (P < 0.05). The results of the quantile g-computation showed that the risk of occurrence of grip strength reduction was -1.007 (95％ confidence interval:-1.362, -0.652; P < 0.001) when each quartile of the mixture of the seven metals was increased. Bayesian kernel function regression model analysis showed that mixtures of the seven metals had a negative overall effect on grip strength, with Cu, As and Sr being negatively associated with grip strength levels. In the total population, potential interactions were observed between As and Mn and between Cu and Mn (Pinteractions of 0.003 and 0.018, respectively).Conclusion In summary, this study suggests that combined exposure to metal mixtures is negatively associated with grip strength. Cu, Sr and As were negatively correlated with grip strength levels, and there were potential interactions between As and Mn and between Cu and Mn.

Objective To investigate the protective effect of silymarin extract(SME)and its complex preparation on ethanol liver injury.Methods An ethanol liver injury model was established by gavage of 12 mL·kg-1 50％ethanol.Male mice were divided into blank group(distilled water),model group(ethanol liver injury model),SME-L,-H groups(6,20 mg·mL-1 SME),SME+Ganoderma lucidum extract(GLE)-L,-H groups(10,30 mg·mL-1 SME+GLE,SME∶GLE=1∶1),Jian An Shi Silymarin Pueraria Mirifica and Tansy tablets(JAS)-L,-H groups(68,204 mg·mL-1 JAS),there were 12 mice in each group.The serum levels of glutamic-oxaloacetic transaminase(GOT)in mice were measured by fully automated biochemical analyzer assay;the serum levels of interleukin-6(IL-6)and tumor necrosis factor-alpha(TNF-α)in mice were measured by enzyme-linked immunosorbent assay(ELASA);the hepatic tissue of oxidative stress indexes[catalase(CAT)and total superoxide dismutase(T-SOD)]were measured by ultraviolet spectrophotometer.Results The T-SOD activity in the blank group,model group,SME-L,SME-H,SME+GLE-L,SME+GLE-H,JAS-L and JAS-H groups were(192.54±49.00),(141.65±34.72),(205.83±32.77),(191.68±25.83),(192.31±28.79),(177.82±32.61),(218.58±74.80)and(210.24±31.65)U·mg·prot-1;CAT activity were(37.78±5.73),(28.92±8.44),(44.12±11.52),(41.41±9.15),(47.01±10.48),(41.63±8.95),(47.14±8.91)and(48.29±10.06)U·mg-1;GPT levels were(47.61±13.00),(97.84±26.00),(62.33±18.92),(51.84±17.91),(70.77±28.00),(58.00±21.27),(52.28±18.78)and(45.55±9.27)U·L-1;IL-6 levels were(21.03±1.52),(28.43±5.75),(21.90±3.24),(21.23±1.55),(22.26±2.58),(21.24±2.91),(22.17±4.14)and(21.14±3.02)pg·mL-1.Comparing the above indexes in the model group with the blank group,and comparing the above indexes in the SME-L,SME-H,SME+GLE-L,SME+GLE-H,JAS-L,JAS-H groups with the model group,the differences were statistically significant(all P＜0.01).The TNF-α levels in blank,model,SME-L,SME-H,SME+GLE-L,SME+GLE-H,JAS-L and JAS-H groups were were(28.07±7.72),(69.02±16.34),(40.29±8.94),(48.84±10.17),(41.91±14.96),(40.07±12.75),(50.72±11.44)and(45.05±11.34)pg·mL-1.Comparing the model group with the blank group,the SME,SME+GLE-L,-M and JAS,-M groups with the model group,the differences were statistically significant(all P＜0.01).Conclusion Silybum marianum extract and its compound preparation can increase the antioxidant level and reduce the inflammation of mouse liver,and have a certain improvement effect on liver injury caused by acute ethanol poisoning.

Objective To investigate the protective effect of cardamomine(CAR)on anthracycline-induced cardiotoxicity in rats by regulating the pyroptosis mediated by Notch/nuclear factor-κB(NF-κB)signal pathway.Methods The rat model of cardiotoxicity was established by intraperitoneal injection of doxorubicin(DOX).The model rats were randomly divided into DOX group,CAR-L group,CAR-H group and Jagged1 group.Another 10 rats were taken as the control group.The control group and the DOX group were given the same amount of 0.9％NaCl.The CAR-L group and CAR-H group were given 40 and 80 mg·kg-1 CAR by gavage,respectively.The Jagged1 group was given 80 mg·kg-1 CAR+and 25 ng·kg-1 Jagged1 by gavage once a day for 4 weeks.Myocardial injury markers creatine kinase isoenzyme(CK-MB)and troponin Ⅰ(cTn Ⅰ)were detected by kit.The expression of pyroptosis protein Nod-like receptor protein 3(NLRP3)and desquamate D(GSDM-D)were observed by immunohistochemistry.The expression of Notch1 and phosphorylated NF-κB p65(p-NF-κB p65)protein in myocardial tissue was detected by Western blotting.Results The levels of CK-MB in control group,DOX group,CAR-L group,CAR-H group and Jagged1 group were(48.51±5.39),(175.93±13.27),(106.83±9.73),(83.71±8.39)and(126.08±9.74)U·L-1;the levels of cTn Ⅰ were(1.95±0.18),(12.46±1.83),(7.15±0.64),(4.13±0.38)and(8.01±0.78)ng·mL-1;the average optical density of NLRP3 protein were 0.19±0.07,0.36±0.05,0.25±0.05,0.21±0.03 and 0.31±0.06;the average optical density of GSDM-D were 0.18±0.04,0.43±0.06,0.24±0.03,0.19±0.04 and 0.32±0.05.There were significant differences in the above indexes between DOX group and control group(all P＜0.05).There were significant differences in the above indexes between CAR-L group,CAR-H group and DOX group(all P＜0.05),and there were significant differences between CAR-L group and CAR-H group(all P＜0.05).The above indexes in Jagged1 group were significantly different from those in CAR-H group(all P＜0.05).Conclusion CAR can improve myocardial injury in DOX cardiotoxic rats,reduce oxidative stress,inflammatory reaction and pyroptosis,and its mechanism may be related to the inhibition of Notch/NF-κB pathway.

Objective To observe the inhibitory effect of Guiqi Yiyuan ointment on tumor growth in mice with Lewis lung cancer,and to explore the molecular mechanism of Guiqi Yiyuan ointment combined with cisplatin through phosphoinositide 3-kinase/protein kinase B/mammalian rapamycin target protein(PI3K/Akt/mTOR)signal pathway.Methods Sixty C57BL/6 mice were randomly divided into 6 groups with 10 mice in each group.Except for the blank group(0.9％NaCl),Lewis lung cancer-bearing mice were randomly divided into model group(0.9％NaCl),control group(0.9％NaCl,cisplatin 5 mg·kg-1)and low,medium,high dose experimental groups(Guiqi Yiyuan ointment 1.6,3.3,6.6 g·kg-1,cisplatin 5 mg·kg-1).Flow cytometry was used to detect bone marrow-derived suppressor cells(MDSCs);the expression of related proteins in tumor tissues was detected by Western blot.Results The tumor inhibition rates in control group and low,medium,high dose experimental groups were(39.87±4.45)％,(45.74±14.97)％,(57.78±4.70)％and(69.82±11.05)％.The proportion of MDSCs in bone marrow of in blank group,model group,control group and low,medium,high dose experimental groups were(36.13±1.08)％,(68.63±2.94)％,(58.93±2.02)％,(58.00±1.50)％,(50.93±5.06)％and(43.07±2.41)％.The protein expressions of p-PI3K/PI3K in model group,control group and low,medium and high experimental groups were 0.97±0.03,0.77±0.02,0.72±0.01,0.68±0.03 and 0.53±0.02;PTEN were 0.21±0.07,0.65±0.07,0.74±0.06,0.99±0.13,1.11±0.13;p-Akt/Akt were 1.01±0.02,0.82±0.02,0.77±0.00,0.72±0.03 and 0.52±0.04;p-mTOR/mTOR were 1.01±0.01,0.76±0.05,0.69±0.07,0.59±0.06 and 0.47±0.06.There were significant differences between low,medium,high experimental groups and control group(all P＜0.05).Conclusion Guiqi Yiyuan ointment combined with cisplatin can significantly improve the quality of life and inhibit tumor growth in mice.The mechanism may be the inhibition of PI3K/Akt/mTOR signal pathway and the enhancement of tumor cell apoptosis and autophagy.

Objective To observe the effects of traditional Chinese medicine compound Platycodon grandiflorum Bai powder on the growth of subcutaneously implanted tumor and the expression of B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),cysteinyl aspartate specific proteinase(caspase)-3 and caspase-9 in subcutaneously implanted tumor of Lewis lung cancer mice.Methods The model of transplanted tumor of Lewis lung cancer in mice was established.Seventy SPF male C57BL/6 mice were randomly divided into blank group,model group,low dose experimental group,medium dose experimental group,high dose experimental group,control group and combined group.Blank group and model group were given 0.9％NaCl 0.2 mL by gavage;control group was given 0.9％NaCl by gavage and 25 mg·kg-1cisplatin intraperitoneally;high,medium,low dose experimental groups were given 193,96,48 mg·kg-1·d-1 Platycodon grandiflorum Bai powder 0.2 mL by gavage,respectively;combined group was given 96 mg·kg-1·d-1 Platycodon grandiflorum Bai powder 0.2 mL by gavage,and 25 mg·kg-1 cisplatin intraperitoneally,once every other day.The myelogenous suppressor cells(MDSCs)of mouse bone marrow were detected by flow cytometry,and the expressions of Bel-2,Bax,caspase-3 and caspase-9 in tumor cells were detected by immunofluorescence.Results The percentage of MDSCs in bone marrow of mice in blank group,model group,low dose experimental,medium,high dose experimental group,control group and combination group were(32.50±2.76)％,(63.13±3.14)％,(48.43±2.23)％,(42.53±1.28)％,(32.93±3.56)％,(51.30±4.25)％and(19.90±6.21)％,respectively.The fluorescence intensities of Bax in model group,low dose experimental group,medium dose experimental group,high dose experimental group,control group and combination group were 10.42±0.68,12.40±1.23,15.14±0.65,22.95±1.76,27.18±1.62 and 31.61±1.28;Bel-2 were 36.85±0.80,33.92±4.20,28.88±1.01,20.04±2.21,15.69±2.36 and 6.05±0.73;caspase-3 were 5.28±0.44,7.63±0.55,9.66±0.85,14.73±1.18,17.95±1.29 and 22.92±1.95;caspase-9 were 9.48±0.90,11.57±0.72,13.45±0.93,15.73±1.44,19.20±0.96 and 23.21±1.51.There were significant differences between medium,high dose experimental groups and model group(all P＜0.05),and there were significant differences between combined group and control group(all P＜0.05).Conclusion Platycodon grandiflorum Bai powder can up-regulating the expression of Bax,caspase-3 and caspase-9,down-regulating the expression of Bel-2,inhibiting MDSCs,promoting tumor cell apoptosis and inhibiting tumor growth.

Objective To construct machine learning models that can be used to predict AUC fold change(FC)using a database of existing pharmacokinetic(PK)and drug-drug interaction(DDI)information,which can be used to explore the possibility of predicting existing drug interactions and to provide certain rational recommendations for clinical drug use.Methods PK data of DDIs and AUC fold change data were extracted from FDA-approved drug labels.Peptide and pharmacodynamic(PD)information related to drug interactions were retrieved through DrugBank,and PPDT identification of relevant peptide IDs was performed using Protein Resource(UniProt),and a matrix normalization code was used to generate multidimensional vector data that were easy to analysis.The effect of PPDT on the AUC,and the resulting multiplicity change was used as the dependent variable for machine learning model construction.The model with the smallest root mean square error(RMES)value was used for model construction to train a bagged decision tree(Bagged)prediction model.The models were tested using the trained models for some of the drug tests.The models were evaluated by reviewing the available literature findings on detection of drug interaction pairs and analyzing and comparing the predicted values.Results A total of 16 pairs of model drug pairs were tested for the effects of 16 drugs on tacrolimus,and it was found that the accuracy of the prediction of the presence or absence of drug interactions was 81.25％;the prediction results were classified according to the FDA standard classification of the strong and weak for the strength of drug interactions,and the results showed that the prediction of the strength of drug interactions,with a large deviation from the larger prediction was less.Conclusion The evaluation of the model to predict the presence or absence of drug interactions was general;however,after classifying the strengths and weaknesses of drug interactions,the prediction of drug interactions was better,and the prediction results indicated that the model prediction performance has a certain reference value for potential DDI assessment before clinical trials.