Natural products are important sources of drug discovery. However, the traditional methods of extraction and isolation, as well as chemical synthesis for obtaining natural products are associated with issues such as operational complexity, high costs, low efficiency, and environmental pollution. Constructing microbial cell factories through synthetic biology methods to produce medicinal natural products has the advantages of high efficiency, low cost, and environmental protection. Nevertheless, the scope and yield improvement of the products are limited by the limitations of enzymes in microbial cell factories. Protein engineering is considered one of the most effective approaches to overcome these limitations. This article introduces commonly used methods of protein engineering technology and summarizes its specific applications in improving enzyme performance, modifying the enzymatic environment, and promoting the development of synthetic biology tools in the field of pharmaceutical natural product synthesis. Furthermore, it analyzes the current bottlenecks and challenges in protein engineering and looks forward to its future application prospects, offering insights for the development and practical use of protein engineering technology.

Objective To investigate the relationship between single nucleotide polymorphisms(SNPs)in the eNOS gene and genetic susceptibility to systemic lupus erythematosus(SLE)in Hainan.Methods Blood samples were collected from SLE patients(SLE group,n=214)and healthy controls(control group,n=214)from January 2020 to December 2022 at the First Affiliated Hospital of Hainan Medical College and Hainan Provincial People's Hospital.The bases of eNOS gene rs3918188,rs1799983 and rs1007311 loci in each group were detected by SNaPshot sequencing technology.Logistic regression was used to analyze the correlation between genotypes,alleles and gene models(dominant model,recessive model,and overdominant model)of the above 3 target loci of the eNOS gene and genetic susceptibility to SLE.Haplotype analysis was conducted using HaploView 4.2 software to investigate the relationship between haploid and genetic susceptibility to SLE at each site.Results The results of logistic regression analysis revealed that the CC genotype and the C allele at rs3918188 locus were risk factors for genetic susceptibility to SLE(CC vs.AA:OR=2.449,P<0.05;C vs.A:OR=2.133,P<0.001).In recessive model at rs3918188 locus,CC genotype carriers had an increased risk of SLE development compared with AA+AC genotype carriers(OR=2.774,P<0.001).In contrast,in overdominant model at this locus,AC genotype carriers had a decreased risk of SLE occurrence compared with AA+CC genotype carriers(OR=0.385,P<0.001).In addition,polymorphisms of rs1799983 and rs1007311 were not associated with susceptibility to SLE in genotype,allele type and the 3 genetic models(P>0.05).Haplotype analysis revealed a strong linkage disequilibrium between the rs1007311 and rs1799983 loci of the eNOS gene,but no significant correlation was found between haplotype and genetic susceptibility to SLE(P>0.05).Conclusion The CC genotype and C allele at rs3918188 locus of eNOS gene may be risk factors for SLE in Hainan,while the risk of SLE occurrence is reduced in carriers of AC genotype under the overdominant model.

Both anti-glomerular basement membrane (GBM) disease and the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are common causes of pulmonary-renal syndrome. Organizing pneumonia (OP), a special pattern of interstitial lung disease, is extremely rare either in AAV or anti-GBM disease. We report an old woman presented with OP on a background of co-presentation with both ANCA and anti-GBM antibodies.
Female ; Humans ; Antibodies, Antineutrophil Cytoplasmic ; Organizing Pneumonia ; Autoantibodies ; Glomerulonephritis ; Anti-Glomerular Basement Membrane Disease ; Pneumonia ; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/complications*

The secondary metabolites of plants are important sources of natural drugs. Betula plants have abundant pharmacological value, complex mechanism and wide applications, which are closely related to the triterpenoids of theirs. Triterpenoids in Betula species are mainly divided into dammarane-type, ocotillol-type, oleanane-type, lupane-type and cycloaltunane-type. The extracts of Betula species have varieties of activities such as anti-tumor, anti-inflammatory, anti-oxidant, anti-bacterial, etc. And the biosynthetic pathways of triterpenoids after 2,3-oxidosqualene are split into four branches of dammarenediol-II, lupeol, cycloartenol and amyrin according to the different oxidosqualene cyclases. This review summarizes the chemical constituents, pharmacological activities and biosynthetic pathways of triterpenoids in Betula plants. It provides a reference for the research and development of new drugs and the production of these triterpenoids in microbial cell factories by synthetic biology methods.

Renal amyloidosis secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare. Here, we reported a 77-year-old woman with ANCA-associated vasculitis. Renal biopsy with Masson trichrome staining showed pauci-immune crescentic glomerulonephritis, and electron microscopy showed amyloid deposition in the mesangial area. Immunofluorescence revealed kappa light chain and lambda light chain negative. Bone marrow biopsy revealed no clonal plasma cell. Finally, she was diagnosed as ANCA-associated vasculitis with secondary renal amyloid A amyloidosis.
Female ; Humans ; Aged ; Glomerulonephritis/diagnosis* ; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/pathology* ; Antibodies, Antineutrophil Cytoplasmic ; Kidney/pathology* ; Amyloidosis/complications*

Carcinoma, Papillary/surgery* ; Humans ; Parapharyngeal Space ; Perivascular Epithelioid Cell Neoplasms ; Thyroid Cancer, Papillary ; Thyroid Neoplasms/surgery*

OBJECTIVE: To investigate the role of tumor necrosis factor receptor-associated factor 6 (TRAF6) in regulating Bacillus Calmette-Guérin (BCG)-induced macrophage apoptosis. METHODS: The expression of TRAF6 in peripheral blood samples of 50 patients with active tuberculosis (TB) and 50 healthy individuals were detected using quantitative real-time PCR (qPCR). RAW264.7 macrophages were infected with BCG at different MOI and for different lengths of time, and the changes in expressions of Caspase 3 and TRAF6 were detected with Western blotting and qPCR. In a RAW264.7 cell model of BCG infection with TRAF6 knockdown established using RNA interference technique, the bacterial load was measured and cell apoptotic rate and mitochondrial membrane potential (MMP) were determined with flow cytometry. The expression levels of TRAF6, Caspase 3, PARP, BAX and Bcl-2 in the cells were detected using Western blotting, and the expressions of TRAF6 and Caspase 3 were also examined with immunofluorescence assay. RESULTS: The expression of TRAF6 was significantly upregulated in the peripheral blood of patients with active TB as compared with healthy subjects (P < 0.001). In RAW264.7 cells, BCG infection significantly increased the expressions of Caspase 3 and TRAF6, which were the highest in cells infected for 18 h and at the MOI of 15. TRAF6 knockdown caused a significant increase of bacterial load in BCG-infected macrophages (P=0.05), lowered the cell apoptotic rate (P < 0.001) and reduced the expressions of Caspase 3 (P=0.002) and PARP (P < 0.001). BCG-infected RAW264.7 cells showed a significantly increased MMP (P < 0.001), which was lowered by TRAF6 knockdown (P < 0.001); the cells with both TRAF6 knockdown and BCG infection showed a lowered BAX expression (P=0.005) and an increased expression of Bcl-2 (P=0.04). CONCLUSION TRAF6 promotes BCG-induced macrophage apoptosis by regulating the intrinsic apoptosis pathway.
Apoptosis ; BCG Vaccine ; Caspase 3/metabolism* ; Humans ; Intracellular Signaling Peptides and Proteins ; Macrophages ; Mycobacterium bovis/metabolism* ; Poly(ADP-ribose) Polymerase Inhibitors ; TNF Receptor-Associated Factor 6/metabolism* ; bcl-2-Associated X Protein/metabolism*

Qishen Yiqi Dripping Pills(QSYQ) are used clinically to treat various myocardial ischemic diseases, such as angina pectoris, myocardial infarction, and heart failure; however, the molecular mechanism of QSYQ remains unclear, and the scientific connotation of traditional Chinese medicine(TCM) compatibility has not been systematically explained. The present study attempted to screen the critical pathway of QSYQ in the treatment of myocardial ischemia by network pharmacology and verify the therapeutic efficacy with the oxygen-glucose deprivation(OGD) model, in order to reveal the molecular mechanism of QSYQ based on the critical pathway. The key targets of QSYQ were determined by active ingredient identification and target prediction, and underwent pathway enrichment analysis and functional annotation with David database to reveal the biological role and the critical pathway of QSYQ. Cell counting Kit-8(CCK-8), lactate dehydrogenase(LDH), and Western blot tests were launched on high-content active ingredients with OGD cell model to reveal the molecular mechanism of QSYQ based on the critical pathway. The results of network pharmacology indicated that QSYQ, containing 18 active ingredients and 82 key targets, could protect cardiomyocytes by regulating biological functions, such as nitric oxide biosynthesis, apoptosis, inflammation, and angiogenesis, through TNF signaling pathway, HIF-1 signaling pathway, PI3 K-Akt signaling pathway, etc. HIF-1 signaling pathway was the critical pathway. As revealed by CCK-8 and LDH tests, astragaloside Ⅳ, salvianic acid A, and ginsenoside Rg_1 in QSYQ could enhance cell viability and reduce LDH in the cell supernatant in a concentration-dependent manner(P<0.05). As demonstrated by the Western blot test, astragaloside Ⅳ significantly down-regulated the protein expression of serine/threonine-protein kinase(Akt1) and hypoxia-inducible factor 1α(HIF-1α) in the HIF-1 signaling pathway, and up-regulated the protein expression of vascular endothelial growth factor A(VEGFA). Salvianic acid A significantly down-regulated the protein expression of upstream phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha(PIK3 CA) and downstream HIF-1α of Akt1. Ginsenoside Rg_1 significantly down-regulated the expression of HIF-1α protein and up-regulated the expression of VEGFA. The therapeutic efficacy of QSYQ on myocardial ischemia was achieved by multiple targets and multiple pathways, with the HIF-1 signaling pathway serving as the critical one. The active ingredients of QSYQ could protect cardiomyocytes synergistically by regulating the targets in the HIF-1 signaling pathway to inhibit its expression.
Drugs, Chinese Herbal/pharmacology* ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; Myocardial Ischemia/genetics* ; Signal Transduction ; Vascular Endothelial Growth Factor A

BACKGROUND: The treatment mode of lung cancer is epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) as a first-line treatment for patients with EGFR mutant in non-small cell lung cancer (NSCLC). At the same time programmed death receptor 1 (PD-1) and its programmed death receptor ligand 1 (PD-L1) inhibitors therapy as the representative immune checkpoint inhibitors (ICIs) has a significant effect in the treatment of lung cancer. The aim of this study was to investigate the correlation between the expression of PD-1 and PD-L1 in NSCLC and clinicopathologic feature, EGFR gene mutation. METHODS: The protein expression of PD-1 and PD-L1 was detected by immunohistochemistry from 127 patients with NSCLC and EGFR gene mutation was detected by quantitative polymerase chain reaction (qPCR) to analyze its relation with clinicopathologic feature. Also, the correlation between protein expression of PD-1 and PD-L1 and EGFR mutation. RESULTS: The PD-1 positive expression in NSCLC tumor cells and tumor infiltrating immune cells is 53.5% (68/127), PD-L1 is 57.5% (73/127). The PD-1 and PD-L1 expression significantly higher in well-differentiated and moderately-differentiated carcinoma than poorly differentiated carcinoma, I+II than III+IV in clinical staging (P<0.05). The EGFR mutation rate was 46.5% (59/127), correlate with female, without smoking history, adenocarcinoma and well-differentiated and moderately-differentiated patients respectively higher than male, smoking history, squamous carcinoma and poorly differentiated patients (P<0.05). The protein expression of PD-L1 and PD-1 had the consistency in NSCLC patients (kappa=0.107,5, P=0.487). There was a negative correlation between the EGFR mutation and PD-1 and PD-L1 expression (Φ=-0.209, Φ=-0.221, P<0.05). Follow-up of NSCLC patients, the median total survival in under the age of 65, adenocarcinoma, well-differentiated and moderately-differentiated, with PD-L1 expression patients respectively higher than over the age of 65, squamous carcinoma, poorly differentiated, without PD-L1 expression patients (P<0.05). The median survival of hypo expression patients of PD-L1 significantly higher than hyper expression patient (P=0.04). CONCLUSIONS According to the Chinese Expert Consensus on Standards of PD-L1 immunohistochemistry testing for NSCLC, we tested the PD-L1 expression in NSCLC and then the dominant population of anti-PD-1/PD-L1 treatment was screened out. Patients with EGFR mutation were also detected and EGFR mutation was negatively correlated with the expression of PD-1 and PD-L1 as well. On the basis of PD-L1 expression and EGFR mutation status, it may benefit NSCLC patients from individualized treatment. Meanwhile, patients who were under the age of 65, adenocarcinoma, well-differentiated and moderately-differentiated, hypo expression of PD-L1 have a relatively good prognosis, to provide reference for the prognosis evaluation of NSCLC.

10-Deacetylbaccatin III (10-DAB) C10 acetylation is an indispensable procedure for Taxol semi-synthesis, which often requires harsh conditions. 10-Deacetylbaccatin III-10-