1.Osthole protects APAP-induced liver injury in mice by inhibiting the TGF-β1/Smad pathway through upregulation of Tif1γ
Yiran HE ; Yang HE ; Guoyan DENG ; Zhiqiang FAN ; Zizhao TANG ; Feng WEI ; Linqi OUYANG
Chinese Journal of Clinical Pharmacology and Therapeutics 2025;30(7):889-898
AIM:To investigate the protective ef-fect of osthole(Ost)on APAP-induced liver injury in mice and its molecular mechanism.METHODS:We established the APAP-induced liver injury model in mice,and Ost was used to intervene.The expres-sion of AST,ALT,SOD,ROS,MDA,LDH,GSH-PX in mice plasma were detected by biochemical meth-od.HE staining was used to observe the changes of liver tissue structure.Immunofluorescence assay was used to detect the expression of Tif1γ and Smad4 in liver tissue.The mRNA expression of IL-1β,IL-6,TNF-α,Smad4,and Tif1γ were detected by qRT-PCR.Western blot was applied to assess the protein expression of Smad2/3 and pSmad2/3 in liver tissue.RESULTS:Compared with the control group,the liver structure destruction and hepato-cyte death was increased,ALT,AST,ROS,MDA and LDH were increased,while SOD and GSH-PX were decreased,and the mRNA expressions of IL-1β,IL-6 and TNF-α were increased in the model group.Compared with the model group,the Ost interven-tion group had improved liver structure and de-creased liver cell death;decreased ALT,AST,ROS,MDA and LDH,increased SOD and GSH-PX,and de-creased expression of IL-1β,IL-6 and TNF-α mRNA.Compared with the control group,liver tissues of model mice showed increased expression of pS-mad2/3,Smad4 protein and Smad4 mRNA,and de-creased Tif1γ protein and mRNA.Compared with the model group,the liver tissues of the Ost inter-vention group showed decreased expression of pS-mad2/3,Smad4 protein and Smad4 mRNA,and in-creased expression of Tif1γ protein and mRNA.CONCLUSION:Ost can improve liver function,re-duce oxidative stress and inflammatory reaction,and protect hepatocyte damage induced by APAP in mice,which may be related to the up-regulation of Tif1γ and inhibition of TGF-β1/Smad signaling pathway.
2.Construction of p97 mutant of Mesomycoplasma hyopneumoniae based on the homologous recombination system
Yanna WEI ; Jiying WANG ; Huan XIE ; Zhiqiang LI ; Z.A.Ishag HASSAN ; Xing XIE ; Bin XU ; Qiyan XIONG ; Zhixin FENG ; Guoqing SHAO ; Yanfei YU
Chinese Journal of Veterinary Science 2025;45(3):473-481
The aim of this study is to establish an gene editing method of Mesomycoplasma hyo-pneumoniae(Mhp)based on the homologous recombination principle.The restriction enzyme di-gestion and ligation method combined with gene synthesis were used to construct a shuttle plasmid to achieve replication in both Mhp and Escherichia coli(E.coli).The pGEM?-T vector was used as the skeleton.The oriC sequence of Mhp which can achieve the replication of the plasmid in Mhp was inserted into the vector.Sequences of the Spiroplasma promoter and puromycin resistance gene were then inserted into the above constructed plasmid to screen recombinant clones.The up-stream and downstream homologous arms of p97 were constructed to initiate homologous recombination.The recA gene of E.coli is inserted to improve the efficiency of homologous recom-bination.The obtained shuttle plasmid was then delivered into Mhp by electro-transformation or chemical transformation.A shuttle plasmid,pGEM?-Mhp-oriC-p 97,which can replicate in both Mhp and E.coli was constructed.With the transformation of this plasmid,the carried puromycin gene and recA gene can be expressed,the p97 gene can be edited.Finally,the genetically unstable p97 gene mutant was initially obtained.In this study,a tool for Mhp gene editing based on the principle of homologous recombination was established,which laid a foundation for the develop-ment of tools for studying the pathogenesis of Mhp.
3.Application of hydrogel in postoperative treatment of glioblastoma
Yang SHUDE ; Gao SHUO ; Liu KAI ; Feng YUHENG ; Dong ZHIQIANG
Chinese Journal of Clinical Oncology 2025;52(18):957-962
Glioblastoma(GBM)is the most aggressive primary malignant tumor in the central nervous system.GBM frequently recurs after surgery and has limited therapeutic options.Hydrogels,characterized by their injectability,biocompatibility,and controlled drug release,of-fer innovative solutions for postoperative GBM management.Advances in hydrogel technology provide new avenues for personalized GBM treatments with significant clinical potential.This article focuses on the current progress in the research on hydrogels as carriers for chemo-therapeutic drugs,immunomodulatory platforms,and multimodal therapeutic systems.Key strategies,including thermo-and pH-responsive gels,co-delivery systems,and the regulation of macrophage function,are analyzed for their therapeutic efficacy.Additionally,the advant-ages of hydrogels in surgical cavity filling,targeted therapy,and recurrence prevention are highlighted.We also discuss the challenges in clin-ical translation and future directions of hydrogel application in postoperative GBM management.
4.Analysis on the current status and characteristic of clinical trials for oral diseases in China
Jia JU ; Yihuan LIU ; Hongxu YANG ; Shuibing LIU ; Huan ZHANG ; Zhiqiang SHI ; Yuanming SUN ; Bin FENG
Chinese Journal of Stomatology 2025;60(4):394-402
Objective:To understand the current status and characteristics of clinical trials for oral diseases in China, for the purpose of providing a reference for the research and development of oral diseases in China.Methods:Retrieving the information on clinical trials related to oral diseases registered on the "Platforms for drug clinical trial registration and information" of the National Medical Products Administration from the date of the database establishment to December 31, 2024. The number of clinical trials, type of drugs, trial phases, indication, trial scope, design types were statistically analyzed.Results:As of December 31, 2024, a total of 578 drug clinical trials for oral disease were registered, accounting for 2.1% (578/27 905) of the clinical trials disclosed on the platform during the same period. Bioequivalence clinical trials accounted for the highest proportion [73.9% (427/578)], followed by Phase Ⅰ [9.0% (52/578)], Phase Ⅱ [8.0% (46/578)], and Phase Ⅲ [4.5% (26/578)]. The 578 clinical trials involved 149 types of trial drugs, mainly chemical drugs, among which 127 were developed by domestic pharmaceutical enterprises and 27 by international pharmaceutical enterprises (the five investigational drugs have undergone clinical trials by both domestic and international pharmaceutical companies). The project leader units of the 578 drug clinical trials were distributed in 27 provinces, autonomous regions, municipalities, and Hong Kong Special Administrative Region. Excluding 427 bioequivalence clinical trials, the project leader units of 151 new drug clinical trials showed a significant aggregation phenomenon, and only three specialized oral hospitals have served as project leader units for drug clinical trials.Conclusions:The number of drug clinical trials for oral disease in China has generally shown an increasing trend, but there are still problems such as small number of clinical trials, low proportion of investment in new drug development and international multicenter trials, concentrated indications of clinical trials and insufficient clinical trial experience in specialized oral medical institutions. Enhancing the enthusiasm and innovation capabilities of domestic pharmaceutical enterprises in the research and development of oral diseases drugs, exploring the advantages of traditional Chinese medicine/natural medicine resources for oral diseases, and establishing a clinical research system in specialized oral medical institutions are of great significance for the development of oral drugs.
5.The expression of YTHDF2 in cervical lesions and its relationship with prognosis based on bioinformatics
Yushu PENG ; Nan TIAN ; Xinlin FENG ; Rui ZHANG ; Zhaoxia RAN ; Jintao WANG ; Weihong ZHAO ; Zhiqiang TIAN ; Ling DING
Chinese Journal of Epidemiology 2025;46(2):280-287
Objective:To investigate the role of YTHDF2 in cervical lesions and its potential molecular mechanism.Methods:Gene expression data of cervical tissue were obtained from the GEO database to analyze the expression of YTHDF2 mRNA and perform pathway enrichment analysis. Patients with cervical lesions diagnosed by thinprep cytologic test in Gynecological Outpatient Department of Maternal and Child Health Hospital in Jiexiu, Shanxi Province, were selected as the research subjects. Data of cervical lesions and cervical exfoliated cells were collected. HPV infection status was detected by flow-through hybridization, and the expression of YTHDF2 mRNA was detected by reverse transcription real-time polymerase chain reaction. The expression of YTHDF2 in cervical lesions and the mediating role of HPV infection in the relationship between YTHDF2 and squamous intraepithelial lesion (SIL) were evaluated. YTHDF2-related genes were screened from multiple datasets in the GEO and ENCORI databases, and their expression, immune infiltration, and survival analysis were performed to assess the association between YTHDF2 and prognosis. Results:Compared with normal cervical tissue, YTHDF2 was highly expressed in cervical lesion tissue ( P<0.05). A total of 3 672 differentially expressed genes were screened from the dataset GSE49339. Gene Ontology analysis showed that YTHDF2 was mainly involved in transcription regulation. Kyoto Encyclopedia of Genes and Genomes analysis showed that YTHDF2 might be related to HPV infection and other signaling pathways. In the mediation analysis, χ2 test results showed that the expression level of YTHDF2 was significantly different among groups ( χ2=22.47, P<0.001). Trend χ2 test further showed that the expression level of YTHDF2 was upregulated with the degree of cervical precancerous lesions (trend χ2=10.26, P=0.001). Multivariate logistic regression analysis indicated that high YTHDF2 expression increased the risk of low-grade squamous intraepithelial lesions ( OR=3.15, 95% CI: 1.93-5.15) and high-grade squamous intraepithelial lesions ( OR=1.85, 95% CI: 1.01-3.39). Mediation effect analysis revealed a partial mediating effect of HPV infection between YTHDF2 and SIL, accounting for 32.02% of the total effect. Twelve YTHDF2 related genes were screened by the intersection of multiple datasets. The immune infiltration analysis results showed that YTHDF2 and related genes KLF4, E2F3 and HOXC6 were associated with immune infiltration (all P<0.05). Multivariate Cox proportional hazard regression model analysis showed that low expression of KLF4 ( HR=0.53, 95% CI: 0.30-0.94) and high expression of RHOB ( HR=1.80, 95% CI: 1.04-3.13) were risk factors for the prognosis of cervical cancer. Conclusion:YTHDF2 is highly expressed in cervical lesions and may have been involved in the regulation of HPV infection-related pathways and its downstream related genes are related to immune infiltration and prognosis of cervical cancer, providing a theoretical basis for the study of mechanisms related to cervical lesions.
6.Clinical efficacy and safety of a domestic calcipotriol/betamethasone dipropionate ointment in the treatment of stable plaque psoriasis: a multicenter, randomized, double-blind, controlled study
Lixin XIA ; Guang XIANG ; Qingchun DIAO ; Kun HUANG ; Shoumin ZHANG ; Shanshan LI ; Yumei LI ; Zhiqiang SONG ; Qing SUN ; Xiumin YANG ; Meng PAN ; Yuling SHI ; Shuping GUO ; Huiping WANG ; Tiechi LEI ; Xiaoyong ZHOU ; Songmei GENG ; Suchun HOU ; Juan SU ; Yong CUI ; Rixin CHEN ; Yanyan FENG ; Hongxia FENG ; Rushan XIA ; Zudong MENG ; Fang YIN ; Jingjing WANG ; Xinghua GAO
Chinese Journal of Dermatology 2025;58(11):1020-1026
Objective:To evaluate the clinical equivalence between a domestic calcipotriol/betamethasone dipropionate ointment and the originator product in the treatment of stable plaque psoriasis.Methods:A multicenter, randomized, double-blind, three-arm, parallel-group, active- and placebo-controlled study was conducted, and 449 patients aged 18 - 65 years with stable plaque psoriasis were enrolled from 25 hospitals (such as the First Affiliated Hospital of China Medical University). Eligible patients had a baseline physician's global assessment (PGA) score of ≥ 3 points, baseline body surface area (BSA) involvement of 5% - 30%, and a target lesion psoriasis area and severity index (TL-PASI) for plaque elevation of ≥ 3 points. Participants were randomly assigned in a 2:2:1 ratio to the test group ( n = 179), reference group ( n = 180), and placebo group ( n = 90), and applied the domestic calcipotriol/betamethasone dipropionate ointment, originator product, and ointment base respectively, once daily in the evening for 4 weeks. Efficacy and safety were assessed at weeks 1, 2, and 4. The primary efficacy endpoints were the treatment success rates and clinical success rates in each group at week 4. The per-protocol set (PPS) was used for the primary efficacy analysis, and the intention-to-treat (ITT) set for supplementary efficacy analysis. Equivalence between the test and reference preparations was tested using the Cochran-Mantel-Haenszel method adjusted for randomization strata. Superiority of the test and reference preparations over the placebo was also tested. Measurement data were compared among the 3 groups using analysis of variance or non-parametric tests, while treatment success rates, clinical success rates, and incidence rates of adverse reactions were compared using the chi-square test. Results:The ITT, PPS, and safety sets included 447, 420, and 448 patients, respectively. In the ITT set, patients were aged 43.6 ± 12.8 years, including 320 (71.6%) males and 127 (28.4%) females, and the disease duration was 11.21 ± 9.05 years; 316 (70.7%) had a PGA score of 3 points and 131 (29.3%) had a PGA score of 4 - 5 points. No significant differences in the baseline characteristics (including age, sex, disease duration and disease severity) were observed among the 3 groups (all P > 0.05). Based on the PPS analysis, the treatment success rates were 57.9% (99/171) in the test group, 50.3% (86/171) in the reference group, and 7.7% (6/78) in the placebo group, and the clinical success rates were 57.9% (99/171), 50.3% (86/171), and 10.3% (8/78), respectively; both the test and reference groups were superior to the placebo group in both treatment and clinical success rates (all P < 0.001) ; the rate differences for treatment success (90% confidence interval [ CI]: -1.3% - 16.4%) and clinical success (90% CI: -1.3% - 16.3%) between the test and reference groups were entirely within the pre-defined equivalence margin (-20% - 20%). Subgroup analyses by baseline PGA scores: for patients with a baseline PGA score of 3 points, the treatment success rates in the test, reference, and placebo groups were 60.8% (73/120), 52.1% (62/119), and 11.1% (6/54), respectively, and the corresponding clinical success rates were 61.7% (74/120), 53.8% (64/119), and 13% (7/54), respectively; the test and reference groups did not differ significantly in treatment or clinical success rates (both P > 0.05), but both showed higher success rates than the placebo group (all P < 0.001) ; the results of statistical comparisons among the 3 groups in patients with a baseline PGA score of 4 - 5 points were consistent with those observed in patients with a baseline PGA score of 3 points. The percentage reductions in PGA and TL-PASI scores from baseline to weeks 1, 2, and 4 showed significant differences among the 3 groups, which were significantly higher in the test and reference groups than in the placebo group (all P < 0.001), but did not differ between the test and reference groups (all P > 0.05). The primary adverse reactions were local skin reactions, such as pruritus, pain, and erythema. The incidence rates of adverse reactions were 8.9% (16/179) in the test group, 7.3% (13/179) in the reference group, and 7.8% (7/90) in the placebo group, with no significant difference among the 3 groups ( P > 0.05) . Conclusions:The domestic calcipotriol/betamethasone dipropionate ointment demonstrated clinical equivalence to the originator product in the treatment of stable plaque psoriasis, and the two agents exhibited comparable efficacy for patients with varying degrees of disease severity, and were comparable in the speed and degree of clinical improvement, with similar favorable safety profiles.
7.Differences in cytokines expression between mild and severe infant cases infected with respiratory syncytial virus
Guangyu XUE ; Yuting HU ; Kexin ZONG ; Qin LUO ; Shengnan YANG ; Miao FENG ; Xiaoyu YI ; Zhiqiang XIA ; Chen GAO ; Haijun DU ; Ying LI ; Ying CHEN ; Feng HE ; Yajuan WANG ; Yingli QU ; Jin CAO ; Wenyan TIAN ; Qinqin SONG ; Hailan YAO ; Jun HAN
Chinese Journal of Experimental and Clinical Virology 2025;39(3):370-377
Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.
8.Study on the Mechanism of Jiawei Dihuang Decoction in Treating Vascular Dementia and the Exploration on Susceptibility Genes Based on Whole Exome Sequencing Technology
Huiwen YANG ; Juanjuan YANG ; Zhiqiang HAO ; Liangliang CHEN ; Yanfang SHEN ; Peifeng WEI ; Feng MIAO
Chinese Journal of Information on Traditional Chinese Medicine 2025;32(10):134-141
Objective To evaluate the efficacy and safety of Jiawei Dihuang Decoction in the treatment of vascular dementia(VD);To explore its mechanism and the VD susceptibility genesby using whole exome sequencing.Methods A total of 75 patients with VD who were hospitalized or received outpatient treatment at The Second Affiliated Hospital of Shaanxi University of Chinese Medicine were included.They were divided into the control group(37 cases,treated with conventional Western medicine)and the experimental group(38 cases,treated with conventional Western medicine+Jiawei Dihuang Decoction)using random number table method.The treatment course was 3 months.The general data,TCM syndrome scores,MMSE scores,ADL scores,Blessed scores and adverse reactions of the two groups were compared.Peripheral blood samples from 36 patients with kidney-yin deficiency type VD were selected for whole exome sequencing.Susceptible genes were screened,and the targets of Jiawei Dihuang Decoction were analyzed by network pharmacology.A"drug-gene"network was constructed,and key pathways were enriched.Results There was no statistical significance in the baseline data between the two groups(P>0.05),and they were comparable.Compared with before treatment,the MMSE scores of patients in both groups significantly increased after treatment,while TCM syndrome scores and ADL scores significantly decreased(P<0.05).Compared with the control group,the TCM syndrome scores,MMSE scores,ADL scores and clinical efficacy of the experimental group were significantly better than those of the control group(P<0.05).Moreover,the Blessed score showed that the experimental group had more advantages in improving the patients'living ability and daily habits(P<0.05).No adverse reactions were observed in both groups during the treatment period.A total of 1 250 744 single nucleotide polymorphism(SNP)loci and 37 314 insertion and deletion(InDel)loci were detected by whole exome sequencing.After screening,3 041 VD susceptibility genes were obtained.It was found that they were involved in biological processes such as the response to nutrient levels,positive regulation of the MAPK cascade,vascular processes in the circulatory system,the response to nutrients,etc.And enriched in PI3K-Akt,cholinergic/glutamatergic synapses,lipid metabolism and atherosclerosis pathways.The potential targets of 854 of Jiawei Dihuang Decoction were intersected with the susceptibility genes to obtain 353 common targets.The top 10 key genes were analyzed and found to be involved in positive regulation of cytosine-serine phosphorylation,miRNA-mediated gene silencing regulation,and the response of cells to decreased oxygen levels,etc.They were enriched in PI3K-Akt,lipid and atherosclerosis signaling pathways.Conclusion Jiawei Dihuang Decoction can alleviate the symptoms of patients with VD,protect cognitive function,enhance their ability of daily living,and has good safety profile.Its mechanism may involve regulating susceptibility genes through PI3K-Akt signaling pathway and lipid atherosclerosis signaling pathway,and improving lipid metabolism,inflammatory response and oxidative stress.
9.Clinical and genetic characteristics of late-onset facioscapulohumeral muscular dystrophy type 1
Fuze ZHENG ; Xinyue CHEN ; Meng YU ; Liangliang QIU ; Minghui ZENG ; Yuhua LIN ; Feng LIN ; Wei ZHANG ; Minting LIN ; Ning WANG ; Yun YUAN ; Zhiqiang WANG ; Zhaoxia WANG
Chinese Journal of Neurology 2025;58(10):1040-1047
Objective:To summarize the clinical and genetic characteristics of late-onset facioscapulohumeral muscular dystrophy type 1 (FSHD1) patients, and to compare the differences between late-onset and classic-onset FSHD1 patients.Methods:A retrospective analysis was conducted on the clinical and genetic data of genetically confirmed late-onset FSHD1 patients (age at onset30 years) between January 2007 and June 2024 from the Department of Neurology of Peking University First Hospital and the First Affiliated Hospital of Fujian Medical University. Classic-onset FSHD1 patients (10 yearsage at onset≤30 years) were matched 1∶1 according to sex and disease duration for comparison. The demographic information, the number of D4Z4 repeat units, the distal D4Z4 methylation levels, FSHD Clinical Score (CS), Clinical Severity Score (CSS), and Age-Corrected Clinical Severity Score (ACSS) of these patients were collected. Survival analysis was performed to compare the outcome of lower extremity involvement between late-onset and classic-onset FSHD1 patients. The correlation of the number of D4Z4 repeat units and D4Z4 methylation level with CS and ACSS was analyzed in late-onset FSHD1 patients.Results:A total of 61 patients with late-onset FSHD1 were enrolled, 33 (54.1%) of whom are female, with an age of 54.0 (46.0, 62.0) years and a disease duration of 14.0 (5.5, 22.5) years. Compared to classic-onset FSHD1 patients, late-onset patients exhibited significantly lower CS [7.0 (5.6, 8.4) vs 6.0 (4.4, 7.7), U=1 416.000, P=0.013], CSS [3.0 (2.8, 3.3) vs 3.0 (2.0, 4.0), U=2 352.000, P=0.010], and ACSS [189.2 (137.1, 241.3) vs 96.8 (61.3, 132.2), U=3 225.500, P0.001], and higher proportion of patients with limb girdle involvement but no facial muscle involvement [18.0% (11/61) vs 6.6% (4/61), χ2=3.725, P=0.054]. Kaplan-Meier survival analysis showed that the onset age of lower extremity involvement in late-onset patients (45 years, 95% CI 42-48 years) was significantly higher than that in classic-onset patients (24 years, 95% CI 21-27 years, χ2=61.012, P0.001). The duration from symptom onset to lower extremity involvement in late-onset patients (15 years, 95% CI 10-20 years) was significantly longer than that in classic-onset patients (8 years, 95% CI 3-13 years, χ2=9.105, P=0.003). Late-onset FSHD1 patients carried higher average distal D4Z4 methylation levels compared to those with classic-onset FSHD1 [46.68% (40.79%,52.57%) vs 41.02% (34.03%,48.00%), U=1 378.500, P=0.014]. Among late-onset FSHD1 patients, cytosine-phosphate-guanine 6 (CpG6) methylation levels were significantly negatively correlated with ACSS ( r=-0.278, P=0.025); the number of D4Z4 repeat units were significantly negatively correlated with ACSS ( r=-0.272, P=0.034);CpG6 methylation levels were significantly negatively correlated with CS ( r=-0.441, P=0.003), while no correlation was found between number of D4Z4 repeat units and CS ( r=-0.161, P=0.310). Conclusions:Compared with classic-onset FSHD1 patients, late-onset FSHD1 patients are associated with a higher degree of distal D4Z4 methylation, along with a milder muscle weakness phenotype, slower disease progression and a higher proportion of cases without facial muscle involvement. The age at onset can be used as a marker of the severity and prognosis in FSHD1.
10.Metabolic engineering of Escherichia coli for the biosynthesis of O-acetyl-L-homoserine.
Lianggang HUANG ; Feng GAO ; Nuoran XU ; Junping ZHOU ; Kun NIU ; Bo ZHANG ; Zhiqiang LIU ; Yuguo ZHENG
Chinese Journal of Biotechnology 2025;41(1):256-270
O-acetyl-L-homoserine (OAH) is a promising platform compound for the production of L-methionine and other valuable compounds, while its low yield and low conversion rate limit the industrial application. To solve these problems, we constructed a strain for high OAH production with the previously constructed L-homoserine producer Escherichia coli HS33 as the chassis by systematic metabolic engineering. Firstly, PEP accumulation, pyruvate utilization, and OAH synthesis pathway (overexpressing aspB, aspA, and thrAC1034T) were enhanced to obtain an initial strain accumulating 13.37 g/L OAH. Subsequently, the co-factor synthesis genes were integrated to supply reducing power and energy, which increased the yield to 15.79 g/L. The OAH yield of the engineered strain OAH28 was further increased to 17.49 g/L by strengthening the acetic acid reuse pathway, improving the supply of acetyl-CoA, and regulating the expression of MetX from different sources. Finally, in a 5 L fermenter, OAH28 achieved an OAH titer of 47.12 g/L, with a glucose conversion rate of 32% and productivity of 0.59 g/(L·h). The results lay a foundation for increasing the OAH production by metabolic engineering and give insights into the industrial production of OAH.
Metabolic Engineering/methods*
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Escherichia coli/genetics*
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Homoserine/biosynthesis*
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Fermentation

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