1.The Structure and Function of The YopJ Family Effectors in The Bacterial Type III Secretion System
Ao-Ning LI ; Wen-Bo LI ; Yu-Ying LU ; Min-Hui ZHU ; Yu-Long QIN ; Yong ZHAO ; Zhao-Huan ZHANG
Progress in Biochemistry and Biophysics 2026;53(3):516-533
The Type III Secretion System (T3SS) serves as a pivotal virulence apparatus for numerous Gram-negative bacterial pathogens, enabling them to infect both animal and plant hosts. Functioning as a molecular syringe, the T3SS directly translocates bacterial effector proteins from the bacterial cytoplasm into the interior of eukaryotic host cells. These effectors are central weapons that precisely manipulate a wide spectrum of host cellular physiological processes, ranging from cytoskeletal dynamics to immune signaling, to establish a favorable niche for bacterial survival and proliferation. Among the diverse arsenal of T3SS effectors, the YopJ family constitutes a critical group of virulence factors. Members of this family are characterized by a conserved catalytic triad structure—a hallmark of the CE clan of cysteine proteases that has been evolutionarily repurposed to confer acetyltransferase activity. A defining and intriguing feature of these enzymes is their stringent dependence on a host-derived eukaryotic cofactor, inositol hexakisphosphate (IP6), for allosteric activation. This requirement acts as a sophisticated molecular safeguard, ensuring enzymatic activity only within the appropriate host environment, thereby preventing detrimental effects on the bacterium itself. While seminal studies on individual members such as Yersinia’s YopJ and Salmonella’s AvrA have provided deep mechanistic insights, a systematic and integrative understanding of the structure-function relationships across the entire family remains fragmented. Key questions persist regarding how a conserved catalytic core has diverged to recognize distinct host substrates in different kingdoms of life. To address this gap, this article provides a systematic review of the YopJ family, focusing on three interconnected aspects: their structural features, their catalytic mechanism, and their divergent immunosuppressive strategies in animal versus plant hosts. By conducting a comparative analysis of the sequences and resolved three-dimensional structures of three representative members (e.g., HopZ1a, PopP2, AvrA), we elucidate regions of significant variation embedded within the conserved core catalytic architecture. These variable regions, often involving surface loops and substrate-binding interfaces, are crucial determinants of target specificity and functional specialization. The functional divergence of this effector family is most apparent when comparing their modes of action in different hosts. In animal hosts, YopJ-family effectors primarily sabotage innate immune signaling pathways. They achieve this by acetylating key serine and threonine residues within the activation loops of critical kinases in the MAPK and NF‑κB pathways. This post-translational modification blocks the phosphorylation and subsequent activation of these kinases, leading to potent suppression of inflammatory cytokine production. Conversely, in plant hosts, the strategy broadens to dismantle the two-tiered plant immune system. YopJ homologs target a more diverse set of substrates, including immune-associated receptor-like cytoplasmic kinases (RLCKs), microtubule networks via tubulin acetylation (which disrupts cellular trafficking and signaling), and transcription factors central to defense gene regulation. This multi-target approach effectively suppresses both Pattern-Triggered Immunity (PTI) and Effector-Triggered Immunity (ETI). In conclusion, this synthesis aims to deepen the mechanistic understanding of YopJ family-mediated pathogenesis by integrating structural biology with cellular function across host kingdoms. Elucidating the precise molecular basis for substrate selection—how conserved platforms achieve target diversity—is a major frontier. Furthermore, this knowledge provides a vital theoretical foundation for developing novel anti-virulence strategies. Targeting the conserved IP6-binding pocket or the catalytic acetyltransferase activity itself represents a promising avenue for designing broad-spectrum inhibitors that could disarm this critical family of bacterial effectors, potentially offering new therapeutic approaches against a range of pathogenic bacteria.
2.Notoginsenoside R1 modulates mitophagy in human cardiomyocytes viathe Pink1/Parkin pathway after hypoxia/reoxygenation
Xiaoman XIONG ; Huan WU ; Shanglin LU ; Yong WANG ; Yuhua ZHENG ; Yi XIANG ; Haiyan ZHOU ; Xingde LIU
Acta Universitatis Medicinalis Anhui 2026;61(1):53-59
ObjectiveTo investigate the mechanism by which Notoginsenoside R1 (NGR1) ameliorates hypoxia/reoxygenation (H/R)-induced injury in AC16 human cardiomyocyte cell lines through the regulation of mitophagy. MethodsCommon genes linked to hypoxia/reoxygenation injury and mitophagy were identified by intersecting data from GeneCards and MitoCarta databases. AC16 cell viability was assessed via CCK-8 assay under varying NGR1 concentrations (0, 6.25, 12.5, 25, 50, 100, 200, 300, 400, 500 μmol/L). AC16 cells were divided into the following groups: control group (Control), model group (H/R), and treatment groups (H/R + NGR1 at 100, 200 and 300 μmol/L). Mitochondrial membrane potential (ΔΨm) was measured using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining. Transcriptional levels of mitophagy-related genes (Parkin, Pink1, P62) were quantified by reverse transcription-quantitative PCR (RT-qPCR). Protein expression of mitophagy-related markers (Parkin, Pink1, P62, and LC3BⅡ) was evaluated via Western blot analysis. Mitochondrial ultrastructure was visualized by transmission electron microscopy (TEM). ResultsCompared to the control group, cell viability in the H/R group significantly decreased (P<0.01). Treatment with NGR1 at concentrations above 100 μmol/L significantly enhanced the cell viability of AC16 cells compared to the H/R group (P<0.01). H/R induced a significant decrease in mitochondrial membrane potential (P<0.01), which was restored by NGR1 treatment (P<0.01). The mRNA levels of Parkin, Pink1, and P62 in the H/R group were upregulated compared to the control group (P<0.05), while NGR1 intervention downregulated their expression (P<0.05). Protein expression levels of Parkin, Pink1, and LC3BⅡ in the H/R group significantly increased, while P62 expression decreased compared to the control group (P<0.01). In contrast, different doses of NGR1 treatment significantly reduced the expression of Parkin, Pink1, and LC3BⅡ while increasing P62 expression (P<0.05). TEM revealed that the mitochondrial structure in the H/R group was severely disrupted, with fragmented and disorganized cristae, which was alleviated by NGR1. ConclusionNGR1 ameliorates H/R-induced AC16 cell injury, and its mechanism may be associated with modulating the Pink1/Parkin pathway to suppress excessive mitophagy.
3.Risk factors for painful diabetic neuropathy in type 2 diabetes mellitus
Xiaojun CAO ; Mengjie TANG ; Limin SHEN ; Ya SHEN ; Yezi SUN ; Huan LU
Journal of Public Health and Preventive Medicine 2026;37(3):168-171
Objective To explore the risk factors of painful diabetic neuropathy (PDN) in patients with type 2 diabetes mellitus (T2DM). Methods A total of 269 patients with type 2 diabetes mellitus (T2DM) who were treated in the Department of Endocrinology at Zhangjiagang Hospital Affiliated to Soochow University from January 2020 to December 2024 were selected. The patients were divided into two groups: T2DM without PDN (n=190) and T2DM with PDN (n=79). The general characteristics and biochemical indicators of the two groups of patients were compared. Multivariate logistic regression was used to analyze the associated factors with PDN in T2DM. The receiver operating characteristic (ROC) curve was used to evaluate fasting C-peptide (FC-P), body mass index (BMI), and disease duration to predict the risk of PDN. Results Compared with the T2DM group without concurrent PDN, the T2DM group with concurrent PDN had a longer disease course, lower BMI, higher HDL-C, lower FC-P, and a higher proportion of diabetic retinopathy. The differences between the two groups were statistically significant (P<0.05). The results of multivariate logistic regression analysis showed that BMI, duration, and FC-P were associated factors of PDN. Conclusion BMI, duration and FC-P are associated factors of painful neuropathy complicated with type 2 diabetes.
4.Research Progress of Vagal Nerve Regulation Mechanism in Acupuncture Treatment of Atrial Fibrillation.
Lu-Lu CAO ; Hui-Rong LIU ; Ya-Jie JI ; Yin-Tao ZHANG ; Bing-Quan WANG ; Xiao-Hong XUE ; Pei WANG ; Zhi-Hui LUO ; Huan-Gan WU
Chinese journal of integrative medicine 2025;31(3):281-288
Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. It has a high prevalence and poor prognosis. The application of antiarrhythmic drugs and even surgery cannot completely treat the disease, and there are many sequelae. AF can be classified into the category of "palpitation" in Chinese medicine according to its symptoms. Acupuncture has a significant effect on AF. The authors find that an important mechanism of acupuncture in AF treatment is to regulate the cardiac vagus nerve. Therefore, this article intends to review the distribution and function of vagus nerve in the heart, the application and the regulatroy effect for the treatment of AF.
Atrial Fibrillation/physiopathology*
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Humans
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Acupuncture Therapy
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Vagus Nerve/physiology*
;
Animals
5.Suppression of Hepatocellular Carcinoma through Apoptosis Induction by Total Alkaloids of Gelsemium elegans Benth.
Ming-Jing JIN ; Yan-Ping LI ; Huan-Si ZHOU ; Yu-Qian ZHAO ; Xiang-Pei ZHAO ; Mei YANG ; Mei-Jing QIN ; Chun-Hua LU
Chinese journal of integrative medicine 2025;31(9):792-801
OBJECTIVE:
To evaluate the anti-hepatocellular carcinoma (HCC) activity of total alkaloids from Gelsemium elegans Benth. (TAG) in vivo and in vitro and to elucidate their potential mechanisms of action through transcriptomic analysis.
METHODS:
TAG extraction was conducted, and the primary components were quantified using high-performance liquid chromatography (HPLC). The effects of TAG (100, 150, and 200 µg/mL) on various tumor cells, including SMMC-7721, HepG2, H22, CAL27, MCF7, HT29, and HCT116, were assessed. Effects of TAG on HCC proliferation and apoptosis were detected by colony formation assays and cell stainings. Caspase-3, Bcl-2, and Bax protein levels were detected by Western blotting. In vivo, a tumor xenograft model was developed using H22 cells. Totally 40 Kunming mice were randomly assigned to model, cyclophosphamide (20 mg/kg), TAG low-dose (TAG-L, 0.5 mg/kg), and TAG high-dose (TAG-H, 1 mg/kg) groups, with 10 mice in each group. Tumor volume, body weight, and tumor weight were recorded and compared during 14-day treatment. Immune organ index were calculated. Tissue changes were oberseved by hematoxylin and eosin staining and immunohistochemistry. Additionally, transcriptomic and metabolomic analyses, as well as quatitative real-time polymerase chain reaction (RT-qPCR), were performed to detect mRNA and metabolite expressions.
RESULTS:
HPLC successfully identified the components of TAG extraction. Live cell imaging and analysis, along with cell viability assays, demonstrated that TAG inhibited the proliferation of SMMC-7721, HepG2, H22, CAL27, MCF7, HT29, and HCT116 cells. Colony formation assays, Hoechst 33258 staining, Rhodamine 123 staining, and Western blotting revealed that TAG not only inhibited HCC proliferation but also promoted apoptosis (P<0.05). In vivo experiments showed that TAG inhibited the growth of solid tumors in HCC in mice (P<0.05). Transcriptomic analysis and RT-qPCR indicated that the inhibition of HCC by TAG was associated with the regulation of the key gene CXCL13.
CONCLUSION
TAG inhibits HCC both in vivo and in vitro, with its inhibitory effect linked to the regulation of the key gene CXCL13.
Animals
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Apoptosis/drug effects*
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Liver Neoplasms/genetics*
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Carcinoma, Hepatocellular/genetics*
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Humans
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Alkaloids/therapeutic use*
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Gelsemium/chemistry*
;
Cell Line, Tumor
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Cell Proliferation/drug effects*
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Mice
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Xenograft Model Antitumor Assays
6.Prrx1 promotes mesangial cell proliferation and kidney fibrosis through YAP in diabetic nephropathy.
Liu XU ; Jiasen SHI ; Huan LI ; Yunfei LIU ; Jingyi WANG ; Xizhi LI ; Dongxue REN ; Sijie LIU ; Heng WANG ; Yinfei LU ; Jinfang SONG ; Lei DU ; Qian LU ; Xiaoxing YIN
Journal of Pharmaceutical Analysis 2025;15(10):101247-101247
Mesangial cell proliferation is an early pathological indicator of diabetic nephropathy (DN). Growing evidence highlights the pivotal role of paired-related homeobox 1 (Prrx1), a key regulator of cellular proliferation and tissue differentiation, in various disease pathogenesis. Notably, Prrx1 is highly expressed in mesangial cells under DN conditions. Both in vitro and in vivo studies have demonstrated that Prrx1 overexpression promotes mesangial cell proliferation and contributes to renal fibrosis in db/m mice. Conversely, Prrx1 knockdown markedly suppresses hyperglycemia-induced mesangial cell proliferation and mitigates renal fibrosis in db/db mice. Mechanistically, Prrx1 directly interacts with the Yes-associated protein 1 (YAP) promoter, leading to the upregulation of YAP expression. This upregulation promotes mesangial cell proliferation and exacerbates renal fibrosis. These findings emphasize the crucial role of Prrx1 upregulation in high glucose-induced mesangial cell proliferation, ultimately leading to renal fibrosis in DN. Therefore, targeting Prrx1 to downregulate its expression presents a promising therapeutic strategy for treating renal fibrosis associated with DN.
7.Effects of human umbilical cord-derived mesenchymal stem cell therapy for cavernous nerve injury-induced erectile dysfunction in the rat model.
Wei WANG ; Ying LIU ; Zi-Hao ZHOU ; Kun PANG ; Jing-Kai WANG ; Peng-Fei HUAN ; Jing-Ru LU ; Tao ZHU ; Zuo-Bin ZHU ; Cong-Hui HAN
Asian Journal of Andrology 2025;27(4):508-515
Stem cell treatment may enhance erectile dysfunction (ED) in individuals with cavernous nerve injury (CNI). Nevertheless, no investigations have directly ascertained the implications of varying amounts of human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) on ED. We compare the efficacy of three various doses of HUC-MSCs as a therapeutic strategy for ED. Sprague-Dawley rats (total = 175) were randomly allocated into five groups. A total of 35 rats underwent sham surgery and 140 rats endured bilateral CNI and were treated with vehicles or doses of HUC-MSCs (1 × 10 6 cells, 5 × 10 6 cells, and 1 × 10 7 cells in 0.1 ml, respectively). Penile tissues were harvested for histological analysis on 1 day, 3 days, 7 days, 14 days, 28 days, 60 days, and 90 days postsurgery. It was found that varying dosages of HUC-MSCs enhanced the erectile function of rats with bilateral CNI and ED. Moreover, there was no significant disparity in the effectiveness of various dosages of HUC-MSCs. However, the expression of endothelial markers (rat endothelial cell antigen-1 [RECA-1] and endothelial nitric oxide synthase [eNOS]), smooth muscle markers (alpha smooth muscle actin [α-SMA] and desmin), and neural markers (neurofilament [RECA-1] and neurogenic nitric oxide synthase [nNOS]) increased significantly with prolonged treatment time. Masson's staining demonstrated an increased in the smooth muscle cell (SMC)/collagen ratio. Significant changes were detected in the microstructures of various types of cells. In vivo imaging system (IVIS) analysis showed that at the 1 st day, the HUC-MSCs implanted moved to the site of damage. Additionally, the oxidative stress levels were dramatically reduced in the penises of rats administered with HUC-MSCs.
Male
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Animals
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Erectile Dysfunction/metabolism*
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Rats, Sprague-Dawley
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Mesenchymal Stem Cell Transplantation/methods*
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Rats
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Penis/pathology*
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Humans
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Disease Models, Animal
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Umbilical Cord/cytology*
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Peripheral Nerve Injuries/complications*
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Mesenchymal Stem Cells
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Nitric Oxide Synthase Type III/metabolism*
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Actins/metabolism*
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Nitric Oxide Synthase Type I/metabolism*
9.Proteomic Preparation Techniques for Formalin-Fixed Paraffin-Embedded Tissue Samples
Ao LU ; Bo MENG ; Jia-Wei ZHAO ; Huan-Yue LIAO ; Zi-Hong YE ; Xiang FANG ; Yang ZHAO
Chinese Journal of Analytical Chemistry 2025;53(1):84-93,中插4-中插8
Twelve pre-processing protocols for formalin-fixed paraffin-embedded(FFPE)tissue samples were developed by orthogonal experimental design,incorporating different dewaxing buffers(Triton X-100 and xylene),lysis buffers(TFE and RapiGest),and enzyme digestion methods(iST,SP3,and FASP)to explore the optimal experimental conditions.These protocols were assessed based on protein and peptide identification depth,identification stability,and quantitative levels of protein abundance.The results indicated that Triton X-100 and xylene minimally impacted proteomics identification,whereas the TFE lysis buffer and iST digestion method significantly enhanced the proteomics analysis of FFPE samples.Considering the potential toxicity of xylene,the TTI protocol based on Triton X-100,TFE,and iST was determined to be the optimal choice.This protocol exhibited the best repeatability and stability,and a higher number of proteins associated with significant biological functions were identified.In conclusion,the established TTI protocol offered an efficient and comprehensive approach for proteomic analysis of FFPE samples,significantly enhancing the repeatability and stability of protein identification.
10.A Sensitive Ion Chromatography-Inductively Coupled Plasma Mass Spectrometry Method for Analysis of Iodine Speciation in Environmental Water Samples
Huan JIANG ; Ning CHEN ; Yan-Yun WANG ; Yu-Kun FAN ; Meng-Ting ZHANG ; Lu-Yuan ZHANG ; Xiao-Lin HOU
Chinese Journal of Analytical Chemistry 2025;53(2):278-288
Iodine speciations in aquatic environments are affected by dissolved oxygen,redox potential,microbial activity,organic matter decomposition,light reaction,etc.Accurate quantification of iodine speciation can not only help to understand the geochemical cycle of iodine,but also help to trace and study environmental processes.Based on the combination of ion chromatography(IC)and inductively coupled plasma mass spectrometry(ICP-MS),a rapid and sensitive method was established for determining the speciations of iodine in environmental water samples including seawater,river water,lake water,rainwater,groundwater,etc.The results presented here showed that IO3?and I?in seawater were quickly separated and measured within 120 s when using guard column AG22 and 8 mmol/L(NH4)2CO3 as the mobile phase.While for lake water,river water and precipitation samples with high soluble organically bond iodine(SOI),an AS22 separation column(250 mm×4 mm)connected with a guard column and using 50 mmol/L(NH4)2CO3 as mobile phase could effectively separate unknown SOI from IO3? to achieve accurate quantification of IO3?.For accurate correction of iodine measurement signal fluctuations,133Cs was directly added to the(NH4)2CO3 mobile phase as an internal standard.The SOI content was calculated by the total iodine concentrations minus the sum of IO3?and I?.The precision of the established iodine speciation analytical method was better than 3.5%,and the standard addition experiment showed that the analytical method was accurate.When the injection volume was 25 μL,the detection limits were 0.011?0.025 μg/L for IO3? and 0.023?0.031 μg/L for I?,respectively.The method was successfully used to analyze IO3?,SOI and I? in environmental water samples,such as seawater,river water,rainwater and groundwater.


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