1.SIRT5 Potentiates Hepatocarcinogenesis by Modulating Protein Acylation in Mice
Yu ZHANG ; Feng-Rui REN ; Jia-Yun LI ; Xiang-Yu CHEN ; Zi-Yi WANG ; Qi SUN ; Jun-Cheng ZHAO ; Ye ZHANG ; Zhen HUANG ; Hao HU ; Tao-Tao WEI ; Min XIAO
Progress in Biochemistry and Biophysics 2026;53(6):1712-1722
ObjectiveHepatocellular carcinoma (HCC) represents 90% of all primary liver cancers. The main risk factors associated with HCC include viral hepatitis (B and/or C), alcohol abuse, and metabolic dysfunction-associated steatotic liver disease (MASLD), which progressively advance to liver fibrosis, cirrhosis, and ultimately evolve into HCC. Surgical resection represents the most effective treatment for HCC, while recent advances in immunotherapy, including immune checkpoint inhibitors and adoptive cell therapies, have provided improved treatment prospects for patients with unresectable HCC. However, the complex metabolic heterogeneity of HCC limits the therapeutic efficacy. Metabolic intermediates acyl-CoA not only provide energy and substrates for numerous biochemical reactions but also serve as donors for protein lysine acylation, a major class of post-translational modification (PTM). Therefore, a deeper understanding of the molecular mechanisms underlying protein lysine acylation and hepatocarcinogenesis is urgently needed. MethodsThe levels of protein lysine acylation and silence information regulator 5 (SIRT5) expression levels in clinical HCC samples were analyzed by Western blot. Quantitative malonylome and succinylome of HCC samples were analyzed by antibody-based affinity enrichment coupled with tandem mass spectrometry. The proliferation of HCC cells was analyzed with Cell Counting Kit-8 (CCK-8) assays, the apoptosis was quantified by Annexin V-FITC/propidium iodide (PI) staining coupled with flow cytometry, and the ability of cells to migrate was assayed by Transwell assays. The enzymatic activity of glutathione S-transferase Mu 1 (GSTM1) was quantified. Transgenic mice with hepatic overexpression of SIRT5 were constructed using CRISPR-Cas9, and primary hepatocarcinogenesis was induced by administration of diethylnitrosamine. ResultsWestern blot analysis indicated that the expression level of SIRT5 was elevated in clinical samples from HCC patients, and the levels of lysine malonylation, glutarylation, and succinylation were significantly reduced in HCC tissues. Knockout of SIRT5 in MHCC-97H and MHCC-97L hepatoma cells suppressed cell proliferation, and increased the percentage of apoptotic cells significantly. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the differentially malonylome and succinylome of HCC samples revealed significant enrichment in two major classes of biological processes: core energy metabolism (e.g., glycolysis/gluconeogenesis, tricarboxylic acid metabolic process, fatty acid beta oxidation) and detoxification and oxidative stress response (e.g., response to toxic substance, chemical carcinogenesis, reactive oxygen species (ROS)). SIRT5 removes malonylation from lysine residues in GSTM1 and restores its detoxification activity, which is crucial for the survival of hepatocytes under stressed conditions. More importantly, in vivo experiment indicated that hepatic-specific overexpression of SIRT5 in mice accelerated diethylnitrosamine-induced liver fibrosis and hepatocarcinogenesis, indicating the critical role of SIRT5 in HCC progression. ConclusionThis study highlights the previously unrecognized SIRT5-GSTM1 axis as a key regulator in hepatocarcinogenesis, and suggests a potential target for the treatment of patients with HCC.
2.Design Strategies and Antitumor Applications of Zinc-based Nanomaterials for Achieving “Zinc Overload”
Rong WANG ; Lu ZHAO ; Yun-Feng BAI ; Feng FENG
Progress in Biochemistry and Biophysics 2026;53(7):1896-1913
“Zinc overload” has emerged as a promising strategy in tumor nanomedicine, wherein exogenous modulation of metal ion homeostasis selectively triggers cancer cell death. Among various bioactive ions, zinc (Zn2+) stands out due to its unique ability to simultaneously disrupt energy metabolism, damage mitochondria, degrade mutant p53, and activate antitumor immunity. Notably, tumor cells exhibit greater sensitivity to Zn2+ overload while normal cells maintain higher tolerance. This review systematically summarizes design strategies for achieving “zinc overload” using biodegradable zinc-based nanomaterials, focusing on two fundamental questions: how to specifically deliver Zn2+ to tumors (targeted delivery), and how to trigger controlled release at the tumor site (release strategies). Current challenges are critically analyzed and future perspectives are offered. For targeted delivery, the strategies are categorized into passive, active, and biomimetic approaches. Passive targeting relies on the enhanced permeability and retention (EPR) effect but suffers from poor enrichment efficiency and rapid clearance. Active targeting conjugates ligands (e.g., folic acid, hyaluronic acid) to recognize overexpressed receptors, significantly enhancing cellular uptake. It is emphasized that hyaluronic acid-modified ZIF-8 can co-deliver siRNA for GLUT1 silencing, achieving systematic energy exhaustion. Biomimetic delivery using cell membranes confers immune evasion, prolonged circulation, and homologous targeting, exhibiting the lowest off-target toxicity. This approach is considered to guide future nanocarrier design. For Zn2+ release, 4 mechanisms are discussed. Endogenous environment-responsive release exploits acidic pH to degrade materials like ZIF-8 or ZnO, causing mitochondrial dysfunction, reactive oxygen species (ROS) burst, and autophagic blockade. Incorporation of other ions (Ca2+, Mn2+, Ni2+) enables synergistic metabolic interference and immune activation. Exogenous responsive release using near-infrared light offers spatiotemporally precise activation. For example, a nanorobot combining black phosphorus with ZIF-8 accelerates Zn2+ release under dual acid and light stimuli. Ion exchange represents an elegant trigger: zinc complexes (e.g., Zn-carnosine) have higher affinity for Cu2+; competitive coordination releases Zn2+ while depleting Cu2+, dually inhibiting oxidative phosphorylation and glycolysis. This mechanism is proposed to hold promise for overcoming metabolic reprogramming. Finally, biological regulation—silencing the ZnT1 zinc transporter to block Zn2+ efflux—represents a paradigm shift from passive delivery to active homeostatic disruption. This “block and attack” strategy may prevent acquired resistance. The therapeutic consequences of zinc overload are multifaceted. Zn2+ causes lysosomal membrane permeabilization and impaired SNARE complex formation, blocking autophagic flux and inducing a distinct cell death termed “zincosis”. In mitochondria, Zn2+ inhibits glutathione reductase, causing oxidative stress and electron transport chain blockade. Meanwhile, Zn2+ suppresses glycolytic enzymes (GAPDH, LDHA), leading to ATP depletion and reversing drug resistance by downregulating P-glycoprotein. Moreover, zinc overload triggers immunogenic cell death, promoting dendritic cell maturation and CD8+ T cell infiltration. Combined with cGAS-STING activation, this reshapes the immunosuppressive tumor microenvironment and inhibits distant metastasis. These interconnected mechanisms endow zinc overload with a unique advantage over single-modality treatments. Despite remarkable preclinical efficacy, challenges remain: systemic toxicity from off-target release, potential zinc tolerance via metallothionein upregulation, and insufficient pharmacokinetic data. Future directions should prioritize: (1) intelligent stimuli-responsive materials; (2) combination with immune checkpoint inhibitors;(3) theragnostic integration; (4) deeper mechanistic studies; and (5) artificial intelligence-assisted screening. Zinc overload therapy is expected to become an indispensable component of integrated tumor treatment.
3.Role of SWI/SNF Chromatin Remodeling Complex in Tumor Drug Resistance
Gui-Zhen ZHU ; Qiao YE ; Yuan LUO ; Jie PENG ; Lu WANG ; Zhao-Ting YANG ; Feng-Sen DUAN ; Bing-Qian GUO ; Zhu-Song MEI ; Guang-Yun WANG
Progress in Biochemistry and Biophysics 2025;52(1):20-31
Tumor drug resistance is an important problem in the failure of chemotherapy and targeted drug therapy, which is a complex process involving chromatin remodeling. SWI/SNF is one of the most studied ATP-dependent chromatin remodeling complexes in tumorigenesis, which plays an important role in the coordination of chromatin structural stability, gene expression, and post-translation modification. However, its mechanism in tumor drug resistance has not been systematically combed. SWI/SNF can be divided into 3 types according to its subunit composition: BAF, PBAF, and ncBAF. These 3 subtypes all contain two mutually exclusive ATPase catalytic subunits (SMARCA2 or SMARCA4), core subunits (SMARCC1 and SMARCD1), and regulatory subunits (ARID1A, PBRM1, and ACTB, etc.), which can control gene expression by regulating chromatin structure. The change of SWI/SNF complex subunits is one of the important factors of tumor drug resistance and progress. SMARCA4 and ARID1A are the most widely studied subunits in tumor drug resistance. Low expression of SMARCA4 can lead to the deletion of the transcription inhibitor of the BCL2L1 gene in mantle cell lymphoma, which will result in transcription up-regulation and significant resistance to the combination therapy of ibrutinib and venetoclax. Low expression of SMARCA4 and high expression of SMARCA2 can activate the FGFR1-pERK1/2 signaling pathway in ovarian high-grade serous carcinoma cells, which induces the overexpression of anti-apoptosis gene BCL2 and results in carboplatin resistance. SMARCA4 deletion can up-regulate epithelial-mesenchymal transition (EMT) by activating YAP1 gene expression in triple-negative breast cancer. It can also reduce the expression of Ca2+ channel IP3R3 in ovarian and lung cancer, resulting in the transfer of Ca2+ needed to induce apoptosis from endoplasmic reticulum to mitochondria damage. Thus, these two tumors are resistant to cisplatin. It has been found that verteporfin can overcome the drug resistance induced by SMARCA4 deletion. However, this inhibitor has not been applied in clinical practice. Therefore, it is a promising research direction to develop SWI/SNF ATPase targeted drugs with high oral bioavailability to treat patients with tumor resistance induced by low expression or deletion of SMARCA4. ARID1A deletion can activate the expression of ANXA1 protein in HER2+ breast cancer cells or down-regulate the expression of progesterone receptor B protein in endometrial cancer cells. The drug resistance of these two tumor cells to trastuzumab or progesterone is induced by activating AKT pathway. ARID1A deletion in ovarian cancer can increase the expression of MRP2 protein and make it resistant to carboplatin and paclitaxel. ARID1A deletion also can up-regulate the phosphorylation levels of EGFR, ErbB2, and RAF1 oncogene proteins.The ErbB and VEGF pathway are activated and EMT is increased. As a result, lung adenocarcinoma is resistant to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Although great progress has been made in the research on the mechanism of SWI/SNF complex inducing tumor drug resistance, most of the research is still at the protein level. It is necessary to comprehensively and deeply explore the detailed mechanism of drug resistance from gene, transcription, protein, and metabolite levels by using multi-omics techniques, which can provide sufficient theoretical basis for the diagnosis and treatment of poor tumor prognosis caused by mutation or abnormal expression of SWI/SNF subunits in clinical practice.
4.Impact of posterior cruciate ligament resection on the elasticity of the periarticular soft tissue sleeve in the knee joint.
Yun-Feng ZHANG ; De-Jin YANG ; Zhao-Lun WANG ; Yi-Xin ZHOU ; Hao TANG ; Xiang-Dong WU ; Han-Long ZHENG
China Journal of Orthopaedics and Traumatology 2025;38(10):1055-1060
OBJECTIVE:
To evaluate the effects of posterior cruciate ligament(PCL) resection on soft tissue elasticity and knee stability in total knee arthroplasty(TKA).
METHODS:
Six adult cadaveric knee specimens (involving 10 knees) were included in the study. With the assistance of the robotic system(TiRobot Recon, TINAVI, Beijing), total knee arthroplasty (TKA) was performed sequentially using cruciate retaining (CR) prostheses and posterior stabilizing (PS) prostheses. Between the two surgical procedures, the femoral and tibial osteotomy surfaces were not altered;only the posterior cruciate ligament (PCL) was resected and the intercondylar fossa was treated. After installing the femoral trial component, a soft tissue balance solver was used to apply tension ranging from 30 N to 90 N in 5 N increments at 0°, 10°, and 90° of knee flexion. Meanwhile, the medial and lateral joint gaps were measured synchronously. Based on the tension-gap coupling data, the equivalent elastic coefficients of the medial and lateral soft tissue sleeves at different knee flexion angles, as well as the range of the joint line convergence angle (JLCA) under fixed varus-valgus stress, were calculated. Additionally, the gap balance status under 80 N of tension was analyzed. Self-control comparisons of each indicator were conducted before and after PCL resection to analyze the change patterns.
RESULTS:
After PCL resection, in the fully extended position (knee flexion 0°). The medial equivalent elastic coefficient was 32.2 (25.7, 63.3) N·mm-1 for the CR prosthesis and 27.7 (22.0, 51.9) N·mm-1 for the PS prosthesis, and the statistically significant difference (P=0.013). The range of JLCA was 0.41°(0.26, 0.55)° for the CR prosthesis, which was smaller than 0.75° (0.40, 0.98)° for the PS prosthesis, and the difference was statistically significant(P=0.041). At 90° of knee flexion, the medial joint gap was 10.7(10.1, 11.7) mm for the CR prosthesis, which was smaller than 12.1(10.9, 15.1) mm for the PS prosthesis, with a statistically significant difference(P=0.011). No statistically significant differences were observed in other joint gaps.
CONCLUSION
PCL resection reduces the rigidity of the medial soft tissues in the fully extended knee and increases the medial joint gap in the flexed position, thereby affecting knee stability and balance. This finding suggests that PS and CR prostheses may require different morphological designs, and there should be differences in indications and osteotomy strategies between CR-TKA and PS-TKA. CR-TKA is more suitable for patients with preoperative medial soft tissue laxity.
Humans
;
Posterior Cruciate Ligament/physiopathology*
;
Knee Joint/physiopathology*
;
Arthroplasty, Replacement, Knee
;
Elasticity
;
Male
;
Female
;
Middle Aged
;
Aged
;
Biomechanical Phenomena
;
Adult
5.Dislocations deteriorate postoperative functional outcomes in supination-external rotation ankle fractures.
Sheng-Ye HU ; Mu-Min CAO ; Yuan-Wei ZHANG ; Liu SHI ; Guang-Chun DAI ; Ya-Kuan ZHAO ; Tian XIE ; Hui CHEN ; Yun-Feng RUI
Chinese Journal of Traumatology 2025;28(2):124-129
PURPOSE:
To assess the relationship between dislocation and functional outcomes in supination-external rotation (SER) ankle fractures.
METHODS:
A retrospective case series study was performed on patients with ankle fractures treated surgically at a large trauma center from January 2015 to December 2021. The inclusion criteria were young and middle-aged patients of 18 - 65 years with SER ankle fractures that can be classified by Lauge-Hansen classification and underwent surgery at our trauma center. Exclusion criteria were serious life-threatening diseases, open fractures, fractures delayed for more than 3 weeks, fracture sites ≥ 2, etc. Then patients were divided into dislocation and no-dislocation groups. Patient demographics, injury characteristics, surgery-related outcomes, and postoperative functional outcomes were collected and analyzed. The functional outcomes of SER ankle fractures were assessed postoperatively at 1-year face-to-face follow-up using the foot and ankle outcome score (FAOS) and American Orthopedic Foot and Ankle Society ankle hindfoot score and by 2 experienced orthopedic physicians. Relevant data were analyzed using SPSS version 22.0 by Chi-square or t-test.
RESULTS:
During the study period, there were 371 ankle fractures. Among them, 190 (51.2%) were SER patterns with 69 (36.3%) combined with dislocations. Compared with the no-dislocation group, the dislocation group showed no statistically significant differences in gender, age composition, fracture type, diabetes, or smoking history, preoperative waiting time, operation time, and length of hospital stay (all p > 0.05), but a significantly higher Lauge-Hansen injury grade (p < 0.001) and syndesmotic screw fixation rate (p = 0.033). Moreover, the functional recovery was poorer, revealing a significantly lower FAOS in the sport/rec scale (p < 0.001). Subgroup analysis showed that among SER IV ankle fracture patients, FAOS was much lower in pain (p = 0.042) and sport/rec scales (p < 0.001) for those with dislocations. American Orthopedic Foot and Ankle Society ankle hindfoot score revealed no significant difference between dislocation and no-dislocation patients.
CONCLUSION
Dislocation in SER ankle fractures suggests more severe injury and negatively affects functional recovery, mainly manifested as more pain and poorer motor function, especially in SER IV ankle cases.
Humans
;
Ankle Fractures/physiopathology*
;
Male
;
Female
;
Retrospective Studies
;
Adult
;
Middle Aged
;
Supination
;
Aged
;
Young Adult
;
Rotation
;
Joint Dislocations/surgery*
;
Fracture Fixation, Internal/methods*
;
Adolescent
;
Recovery of Function
;
Treatment Outcome
6.Pharmacological actions of the bioactive compounds of Epimedium on the male reproductive system: current status and future perspective.
Song-Po LIU ; Yun-Fei LI ; Dan ZHANG ; Chun-Yang LI ; Xiao-Fang DAI ; Dong-Feng LAN ; Ji CAI ; He ZHOU ; Tao SONG ; Yan-Yu ZHAO ; Zhi-Xu HE ; Jun TAN ; Ji-Dong ZHANG
Asian Journal of Andrology 2025;27(1):20-29
Compounds isolated from Epimedium include the total flavonoids of Epimedium , icariin, and its metabolites (icaritin, icariside I, and icariside II), which have similar molecular structures. Modern pharmacological research and clinical practice have proved that Epimedium and its active components have a wide range of pharmacological effects, especially in improving sexual function, hormone regulation, anti-osteoporosis, immune function regulation, anti-oxidation, and anti-tumor activity. To date, we still need a comprehensive source of knowledge about the pharmacological effects of Epimedium and its bioactive compounds on the male reproductive system. However, their actions in other tissues have been reviewed in recent years. This review critically focuses on the Epimedium , its bioactive compounds, and the biochemical and molecular mechanisms that modulate vital pathways associated with the male reproductive system. Such intrinsic knowledge will significantly further studies on the Epimedium and its bioactive compounds that protect the male reproductive system and provide some guidances for clinical treatment of related male reproductive disorders.
Male
;
Epimedium/chemistry*
;
Humans
;
Genitalia, Male/drug effects*
;
Flavonoids/therapeutic use*
;
Animals
7.The Valvular Heart Disease-specific Age-adjusted Comorbidity Index (VHD-ACI) score in patients with moderate or severe valvular heart disease.
Mu-Rong XIE ; Bin ZHANG ; Yun-Qing YE ; Zhe LI ; Qing-Rong LIU ; Zhen-Yan ZHAO ; Jun-Xing LV ; De-Jing FENG ; Qing-Hao ZHAO ; Hai-Tong ZHANG ; Zhen-Ya DUAN ; Bin-Cheng WANG ; Shuai GUO ; Yan-Yan ZHAO ; Run-Lin GAO ; Hai-Yan XU ; Yong-Jian WU
Journal of Geriatric Cardiology 2025;22(9):759-774
BACKGROUND:
Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD.
METHODS & RESULTS:
The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology.
CONCLUSION
The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.
8.Plastrum Testudinis Stimulates Bone Formation through Wnt/β-catenin Signaling Pathway Regulated by miR-214.
Qing LIN ; Bi-Yi ZHAO ; Xiao-Yun LI ; Wei-Peng SUN ; Hong-Hao HUANG ; Yu-Mei YANG ; Hao-Yu WANG ; Xiao-Feng ZHU ; Li YANG ; Rong-Hua ZHANG
Chinese journal of integrative medicine 2025;31(8):707-716
OBJECTIVE:
To investigate the Wnt signaling pathway and miRNAs mechanism of extracts of Plastrum Testudinis (PT) in the treatment of osteoporosis (OP).
METHODS:
Thirty female Sprague Dawley rats were randomly divided into 5 groups by random number table method, including sham group, ovariectomized group (OVX), ovariectomized groups treated with high-, medium-, and low-dose PT (160, 80, 40 mg/kg per day, respectively), with 6 rats in each group. Except for the sham group, the other rats underwent bilateral ovariectomy to simulate OP and received PT by oral gavage for 10 consecutive weeks. After treatment, bone mineral density was measured by dual-energy X-ray absorptiometry; bone microstructure was analyzed by micro-computed tomography and hematoxylin and eosin staining; and the expressions of osteogenic differentiation-related factors were detected by immunochemistry, Western blot, and quantitative polymerase chain reaction. In addition, Dickkopf-1 (Dkk-1) was used to inhibit the Wnt signaling pathway in bone marrow mesenchymal stem cells (BMSCs) and miRNA overexpression was used to evaluate the effect of miR-214 on the osteogenic differentiation of BMSCs. Subsequently, PT extract was used to rescue the effects of Dkk-1 and miR-214, and its impacts on the osteogenic differentiation-related factors of BMSCs were evaluated.
RESULTS:
PT-M and PT-L significantly reduced the weight gain in OVX rats (P<0.05). PT also regulated the bone mass and bone microarchitecture of the femur in OVX rats, and increased the expressions of bone formation-related factors including alkaline phosphatase, bone morphogenetic protein type 2, collagen type I alpha 1, and runt-related transcription factor 2 when compared with the OVX group (P<0.05 or P<0.01). Meanwhile, different doses of PT significantly rescued the inhibition of Wnt signaling pathway-related factors in OVX rats, and increased the mRNA or protein expressions of Wnt3a, β-catenin, glycogen synthase kinase-3β, and low-density lipoprotein receptor-related protein 5 (P<0.05 or P<0.01). PT stimulated the osteogenic differentiation of BMSCs inhibited by Dkk-1 and activated the Wnt signaling pathway. In addition, the expression of miR-214 was decreased in OVX rats (P<0.01), and it was negatively correlated with the osteogenic differentiation of BMSCs (P<0.01). MiR-214 mimic inhibited Wnt signaling pathway in BMSCs (P<0.05 or P<0.01). Conversely, PT effectively counteracted the effect of miR-214 mimic, thereby activating the Wnt signaling pathway and stimulating osteogenic differentiation in BMSCs (P<0.05 or P<0.01).
CONCLUSION
PT stimulates bone formation in OVX rats through β-catenin-mediated Wnt signaling pathway, which may be related to inhibiting miR-214 in BMSCs.
Animals
;
MicroRNAs/genetics*
;
Female
;
Rats, Sprague-Dawley
;
Wnt Signaling Pathway/genetics*
;
Osteogenesis/genetics*
;
Mesenchymal Stem Cells/cytology*
;
Cell Differentiation/drug effects*
;
Bone Density/drug effects*
;
Ovariectomy
;
Osteoporosis/drug therapy*
;
beta Catenin/metabolism*
;
Rats
;
Intercellular Signaling Peptides and Proteins/metabolism*
;
Drugs, Chinese Herbal/pharmacology*
9.Label-free Fluorescence Probe Based on Primer Exchange Reaction for High Sensitivity Detection of Apurinic/Apyrimidinic Endonuclease 1
Yun-Hua WANG ; Le-Ru WANG ; Li-Gai YANG ; Jia-Zheng CHEN ; Yu-Run DU ; Jia-Hui HOU ; Xiang ZHAI ; Xu-Hua ZHAO ; Bao-Feng YU
Chinese Journal of Analytical Chemistry 2025;53(3):464-471
Apurinic/apyrimidinic endonuclease 1(APE 1)is a multifunctional protein that plays important roles in DNA repair and regulation of gene expression.Because APE 1 is overexpressed in various cancers,it can serve as a cancer biomarker for aiding clinical diagnosis,guiding therapy,and monitoring prognosis.On this basis,a label-free fluorescent probe was designed based on the primer exchange reaction(PER)strategy for highly sensitive detection of APE 1 activity.In the absence of APE 1,the structure of catalytic hairpin(HP)was stable and could not form G-quadruplex.Therefore,the background fluorescence of this sensing system was very low due to the dissociation of thioflavin T(ThT).In the presence of APE 1,the apurinic/apyrimidinic(AP)site of HP was cleaved by APE 1 and a short nucleic acid fragment that acted as a primer to initiate PER was generated.After PER reaction,a large number of G-quadruplex were produced,which could specifically bind with ThT and resulted in significant increase of fluorescence signal.The combination of low background design of HP and PER amplification made this biosensor had high sensitivity with a detection limit(3σ)of 0.0008 U/mL.Furthermore,the primer sequence was directly generated by the cleavage of APE 1 without additional addition,which not only increased the specificity of the reaction,but also simplified the experiment procedure.Moreover,the use of label-free fluorescence signal reduced the cost of the experiment,and realized rapid detection of APE 1.Finally,this sensor was used to detect APE 1 in human serum samples with spiked recoveries of 91%-104%,proving great potential in study of biological enzyme.
10.Research of Atmospheric Pressure Ion Heat Induced Dissociation Technology
Tian-Xin XIAN ; Tian-Yi ZHAO ; Sen TIAN ; Yun-Jing ZHANG ; Xing-Li HE ; Peng LI ; Ling-Feng LI
Chinese Journal of Analytical Chemistry 2025;53(4):568-578
In the field of substance detection,ion dissociation techniques have become crucial for enhancing qualitative accuracy.By applying external energy to induce dissociation of ions in the substance being analyzed,the internal structural information can be obtained,thereby improving qualitative capabilities.Current research on ion dissociation techniques primarily focuses on tandem mass spectrometry,which typically requires a vacuum environment.However,research on ambient ion dissociation techniques is less developed,with some progress made in the field of tandem ion mobility spectrometry.Recently,the development of field-induced dissociation(FID)in this area has enabled ambient dissociation of various explosive and volatile alcohol ions.Nevertheless,the limitation imposed by the maximum breakdown field of air restricts the energy of the electric field,making it challenging to dissociate ions with high energy requirements,such as those of drugs.To address this issue,in this work,an ambient heat-induced dissociation(HID)technique based on high temperatures was proposed,in which an ambient ion heat-induced dissociation unit was developed and integrated into a home-made ion trap mass spectrometer.Experiments were conducted on four representative drug samples,e.g.methamphetamine,heroin,cocaine,and ketamine.The parent ions mass spectra,low vacuum collision-induced dissociation(CID)mass spectra and ambient HID mass spectra for each sample were obtained.By analyzing and comparing the fragmentation products from ambient and low vacuum dissociation,the feasibility of the ambient HID technique was verified.This technique provided a method for ion dissociation in single mass analyzers without tandem mass spectrometry capability and offered a new research direction for the future development of tandem ion mobility spectrometry.

Result Analysis
Print
Save
E-mail