1.Single-center analysis of unplanned reoperation case after liver transplantation
Zhi CHEN ; Qingqing DAI ; Fan HUANG ; Guobin WANG ; Xiaojun YU ; Ruolin WU ; Liujin HOU ; Zhenghui YE ; Xinghua ZHANG ; Wei WANG ; Xiaoping GENG ; Hongchuan ZHAO
Organ Transplantation 2026;17(3):452-459
Objective To analyze the main causes and risk factors of unplanned reoperation after liver transplantation. Methods The clinical data of 242 liver transplant recipients in the First Affiliated Hospital of Anhui Medical University from January 2015 to December 2024 were retrospectively analyzed. According to whether unplanned reoperation was performed during the same hospitalization after surgery, the recipients were divided into the reoperation group (n=36) and the non-reoperation group (n=206). The preoperative, intraoperative and postoperative data of the two groups, as well as donor and graft-related data, were compared to analyze the risk factors of unplanned reoperation after liver transplantation and the survival status of the two groups. Results Among the 242 liver transplant recipients, 36 underwent unplanned reoperations, with a total of 54 procedures including various laparotomies, endoscopic and interventional surgeries, among which there were 20 laparotomies, 18 endoscopic surgeries and 16 interventional surgeries. The most common cause of unplanned reoperation was biliary complications (20 times), followed by vascular complications (17 times). Compared with the non-reoperation group, the reoperation group had longer graft cold ischemia time, higher postoperative fatality rate of recipients, longer length of stay in the intensive care unit and postoperative hospital stay, and higher total hospitalization costs (all P<0.05). The incidence of unplanned reoperation was higher in recipients who underwent split liver transplantation (P<0.05). Multivariate analysis showed that intraoperative blood loss ≥1 000 mL, positive culture of graft perfusate and split liver transplantation were independent risk factors for unplanned reoperation (all P<0.05). The postoperative 7-day, 1-month, 3-month and 6-month survival rates of recipients in the reoperation group and the non-reoperation group were 100% vs. 98.1%, 88.9% vs. 94.2%, 69.4% vs. 90.8% and 66.7% vs. 90.8%, respectively, and the postoperative survival rate of recipients in the reoperation group was lower than that in the non-reoperation group (P<0.05). Conclusions The main causes of unplanned reoperation after liver transplantation are biliary complications, vascular complications, abdominal incision infection and intra-abdominal hemorrhage. Intraoperative massive blood loss, positive culture of graft perfusate and split liver transplantation are the risk factors associated with unplanned reoperation after liver transplantation.
2.Value of immunoglobulin G/immunoglobulin M ratio in predicting the prognosis of patients with initially unresectable hepatocellular carcinoma treated by transcatheter arterial chemoembolization combined with tyrosine kinase inhibitor and programmed cell death protein-1 inhibitor
Xingzhi LI ; Wei LUO ; Yuan FENG ; Yu CAI ; Xiaohong LIU ; Feixiang WU ; Yong PENG
Journal of Clinical Hepatology 2026;42(1):117-124
ObjectiveTo investigate the association between immunoglobulin G (IgG)/immunoglobulin M (IgM) ratio and prognosis in patients with initially unresectable hepatocellular carcinoma (iuHCC) receiving TTP triple therapy with transcatheter arterial chemoembolization (TACE), tyrosine kinase inhibitor (TKI), and programmed cell death protein-1 (PD-1) inhibitors. MethodsA retrospective analysis was performed for the clinical data of 151 iuHCC patients who received TTP triple therapy in Department of Hepatobiliary Surgery, Guangxi Medical University Cancer Hospital, from November 2019 to December 2022, and according to IgG/IgM ratio, they were divided into high IgG/IgM group (IgG/IgM ratio >13.23) and low IgG/IgM group (IgG/IgM ratio ≤13.23). The t-test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups. The Kaplan-Meier method and the log-rank test were used for survival analysis, and the Cox proportional hazards model was used to investigate the potential influencing factors for overall survival (OS). ResultsThe 151 patients had a median OS of 26.7 months (95% confidence interval [CI]: 19.8-not reached) and a median progression-free survival of 12.5 months (95%CI: 10.4 — 15.8). The objective response rate was 83.4% and the disease control rate was 94.0%. There were no significant differences in baseline data between the high IgG/IgM group and the low IgG/IgM group (all P>0.05). There was a significant difference in median OS between the high IgG/IgM group and the low IgG/IgM group (20.6 months vs not reached, P=0.016). In both the high IgG/IgM group and the low IgG/IgM group, salvage hepatectomy was significantly associated with the improvement in OS (χ2=8.297 and 10.307, both P<0.05). The multivariate analysis showed that high IgG/IgM ratio (hazard ratio [HR]=1.799, 95%CI: 1.077 — 3.006, P=0.025), baseline alpha-fetoprotein >400 ng/mL (HR=1.762, 95%CI: 1.017 — 3.050, P=0.043), and BCLC stage (HR=2.265, 95%CI: 1.212 — 4.232, P=0.010) were independent influencing factors for OS. ConclusionHigh IgG/IgM ratio is associated with a poorer prognosis in iuHCC patients receiving TTP triple therapy, and salvage hepatectomy has a potential value in improving the prognosis of patients with a high IgG/IGM ratio.
3.Inhibition of Epithelial-mesenchymal Transition Mechanism in Chronic Atrophic Gastritis Rats by Banxia Xiexintang via Regulating IL-17/ERK/C/EBPβ Signaling Pathway
Wenyu WU ; Xinyu ZENG ; Hao LI ; Weiqi SUN ; Jiahui REN ; Yang YU ; Tingting ZHOU ; Aili XU ; Wei WEI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(4):1-10
ObjectiveThis study aimed to investigate the action mechanism by which Banxia Xiexintang (BXT) inhibits epithelial-mesenchymal transition (EMT) in chronic atrophic gastritis (CAG) rats by regulating the interleukin-17(IL-17)/extracellular regulated protein kinases(ERK)/CCAAT enhancer binding protein β(C/EBPβ)signaling pathway, thereby providing new theoretical evidence for the treatment of CAG with classic traditional Chinese medicine formulas. MethodsA CAG rat model was established by using the combined factor method. After successful modeling, the rats were randomly divided into the model group, low-, medium-, and high-dose groups (0.549, 1.098, 2.196 g·kg-1, respectively) of BXT, and the positive drug group (vitacoenzyme, 0.3 g·kg-1). A normal control group was also set up. After 8 weeks of intervention, the pathological changes of gastric tissue were evaluated. The enzyme-linked immunosorbent assay (ELISA) was used to detect the contents of IL-17, tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), and C/EBPβ in serum, as well as the contents of EMT markers in gastric mucosal tissue including E-cadherin, N-cadherin, and vimentin. The immunohistochemistry method was employed to determine the localization and protein expression levels of IL-17, p-ERK, and C/EBPβ in gastric mucosal tissue. Western blot was used to detect the protein expressions of C/EBPβ, ERK, and its phosphorylated form (p)-ERK in gastric mucosa. Real-time polymerase chain reaction (Real-time PCR) was applied to measure the mRNA expression levels of ERK, COX-2, and C/EBPβ in gastric mucosa. ResultsCompared with those in the normal control group, the rats in the model group showed gastric mucosal glandular atrophy and inflammatory cell infiltration. The protein and their related mRNA expressions of C/EBPβ, ERK, and p-ERK in gastric mucosa were significantly increased (P<0.05,P<0.01). The levels of IL-17, TNF-α, COX-2, and C/EBPβ in serum were significantly increased (P<0.01). The contents of N-cadherin and vimentin in gastric mucosal tissue were significantly increased, while the content of E-cadherin was significantly decreased (P<0.01). Compared with the model group, after intervention with different doses of BXT, the pathological damage of the gastric mucosa was improved to varying degrees. The protein and mRNA expressions of C/EBPβ, ERK, and p-ERK in gastric mucosa were significantly reduced (P<0.05,P<0.01). The levels of IL-17, TNF-α, COX-2, and C/EBP β in serum were significantly decreased (P<0.01). The contents of N-cadherin and vimentin in gastric mucosa tissue were decreased, while the content of E-cadherin was increased (P<0.05,P<0.01). ConclusionBXT can effectively improve the pathological damage of gastric mucosal tissue in CAG rats. Its action mechanism may be related to reducing the levels of IL-17 and TNF-α in serum, regulating the IL-17/ERK/C/EBPβ signaling pathway and inhibiting the EMT process.
4.Preparation,characterization,and in vitro antitumor activity of Gambogic acid-loaded intelligent responsive liposome-hydrogel nanopreparation
Yu CHEN ; Shengnan HUANG ; Ziang WANG ; Yunlong ZHAO ; Gaojian WEI ; Sinan WU ; Yanbin GUAN ; Xiali ZHU
China Pharmacy 2026;37(5):613-619
OBJECTIVE To prepare an intelligent responsive liposome-hydrogel nanopreparation co-loaded with gambogic acid (GA), and characterize its antitumor activity in vitro . METHODS GA-ICG-Lip-gel was prepared by ethanol injection and cold dissolution, incorporating GA and the photosensitizer indocyanine green (ICG). The appearance and microscopic morphology of GA-ICG-Lip-gel were observed, its encapsulation efficiency and drug loading capacity were measured, and its photothermal conversion performance, photothermal stability, and infrared imaging properties were investigated, along with the determination of its in vitro release profile. Human breast cancer MCF-7 cells were used as objects to investigate the effects of GA-ICG-Lip-gel (or with near-infrared light irradiation) on cell viability, migration ability, and the cellular uptake capacity of GA-ICG-Lip-gel. RESULTS GA-ICG-Lip-gel existed in a solution state at room temperature and transformed into a gel state at 37 ℃. Its microstructure was dense with small pores, and its encapsulation efficiency and drug loading were (96.07±0.86) % and (6.28±1.16) %, respectively. After exposure to near-infrared light, the temperature of GA-ICG-Lip-gel rose above 42 ℃, with no significant attenuation observed in the heating curve. The heating efficiency was dependent on both the irradiation time and drug concentration. Compared to media without gelatinase, the cumulative release rate of GA-ICG-Lip-gel increased in media containing gelatinase. In vitro studies showed that GA-ICG-Lip-gel could be efficiently taken up by MCF-7 cells; GA-ICG-Lip-gel significantly inhibited the viability and migration ability of MCF-7 cells ( P <0.05), and this inhibitory effect was further enhanced under near-infrared light irradiation. CONCLUSIONS This study successfully prepares GA-ICG-Lip-gel, which exhibits favorable photothermal conversion properties and temperature/enzyme dual-responsive drug release characteristics, and demonstrates significant inhibitory effects on the proliferation and migration of breast cancer cells.
5.Research progress on the source and biosynthesis of tetrodotoxin
Wei WU ; Dunning YU ; Xingchi YANG ; Peng SUN ; Zhiyong CHU
Journal of Pharmaceutical Practice and Service 2026;44(1):1-6
Tetrodotoxin(TTX)is a potent neurotoxin known for its specific sodium channel blocking effects, widely used in biomedical research. While TTX has been identified in various marine organisms, its true origin remains unclear, and the specific biosynthetic pathways are yet to be elucidated. The reported sources of TTX and the progress in research on TTX biosynthesis were summarized, with a focus on potential microbial sources of TTX, which could provide scientific reference for the production and biosynthesis studies of TTX.
6.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
7.Epidemiological investigation and analysis of a local dengue fever cluster outbreak in Qingpu District of Shanghai
Changpo LIN ; Wei WANG ; Zhangrui XU ; Yadong MA ; Zhicheng ZHANG ; Xueqin YU ; Chengcheng WANG ; Haoxuan WANG ; Yanli DAI ; Huanyu WU
Shanghai Journal of Preventive Medicine 2026;38(3):206-209
ObjectiveTo analyze the epidemiological characteristics of a local dengue fever cluster outbreak in Qingpu District of Shanghai in 2024, and to provide a reference for subsequent dengue fever prevention and control. MethodsSeven confirmed local dengue fever cases reported through the National Notifiable Infectious Diseases Surveillance System in Qingpu District of Shanghai in 2024 were selected as the research subjects. Descriptive epidemiological methods were used to conduct investigation and analysis from the aspects of onset, medical treatment and reporting, clinical symptoms, travel and contact history within 15 days before onset, and activity trajectories. ResultsA total of 7 cases were identified in this outbreak. None of the cases had a travel history to dengue-endemic areas within 15 days prior to onset, while all had shared exposure environments and mosquito bite histories, indicating a local clustered transmission pattern. The main clinical manifestations included fever (100.00%) and myalgia (42.86%). All 7 cases were positive for dengue virus serotype 2 (DENV-2) by nucleic acid testing. Genetic sequencing showed that the virus strains belonged to the Cosmopolitan genotype and were most closely related to the epidemic DENV strains circulating in southern China in recent years. ConclusionThis outbreak might be a local secondary infection caused by the short-term stay of dengue fever-infected individuals, and the possible source of importation was dengue fever endemic areas in southern China.
8.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
9.Effect of Huanglian Jiedutang in Regulating Ferroptosis in Mice with Atherosclerosis Based on Nrf2/GPX4 Signaling Pathway
Zhaohui GONG ; Li GAO ; Huiqi ZHAI ; Jinzi YU ; Qingmin CHU ; Chuanjin LUO ; Lijin QING ; Wei WU ; Rong LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(3):22-28
ObjectiveTo study the mechanism of Huanglian Jiedutang (HLJDT) in treating mice with atherosclerosis (AS) by improving ferroptosis. MethodsA total of 10 SPF C57BL/6J mice were selected as a normal group, and 50 ApoE-/- mice were randomly divided into five groups: model group, low-dose group of HLJDT, medium-dose group of HLJDT, high-dose group of HLJDT, and atorvastatin (ATV) group. ApoE-/- mice were fed a high-fat diet for eight weeks to establish the AS model, and at the 9th week, they were given normal saline, low, medium, and high doses of HLJDT (3.9, 7.8, 15.6 g·kg-1·d-1), and atorvastatin calcium tablets (0.01 g·kg-1·d-1), respectively, for a total of eight weeks. The formation of aortic plaque in mice was observed by gross oil red O staining and Masson staining. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) in blood fat were measured by the automatic biochemical analyzer, and the mitochondrial structure of the aorta was observed by transmission electron microscopy. The content of serum superoxide dismutase (SOD) in serum was detected by enzyme-linked immunosorbent assay (ELISA). The content of reduced glutathione (GSH) in serum was detected by the microplate method, and that of malondialdehyde (MDA) in serum was detected by the TBA method. The protein expression of nuclear factor E2-associated factor 2 (Nrf2)/glutathione peroxidase 4 (GPX4) signaling pathway was detected by Western blot. ResultsCompared with those of the normal group, the contents of TC, LDL-C, TG, HDL-C, and MDA in the serum and the aortic vascular plaque deposition of the model group were significantly increased (P<0.01), while the expression levels of SOD and GSH in serum, as well as Nrf2, solute carrier family 7 member 11 (SLC7A11), and GPX4 in aorta were significantly decreased (P<0.01). Mice in the model group appeared mitochondrial fragmentation and vacuolation in the aorta, volume atrophy, mitochondrial crista reduction, or a loose and disorganized form. Compared with those in the model group, the aortic vascular plaque deposition was significantly decreased in the low-dose, medium-dose, and high-dose groups of HLJDT and ATV group, and the contents of serum TC, LDL-C, TG, and MDA in serum were significantly decreased (P<0.05, P<0.01). The contents of serum SOD and GSH and the expression levels of Nrf2, SLC7A11, and GPX4 in the aorta were increased (P<0.05, P<0.01), and the symptoms of aortic mitochondrial vacuolation were alleviated. The number of cristae was increased, and they were ordered neatly. ConclusionHLJDT can reduce aortic vascular plaque deposition, decrease blood lipid and MDA expression, increase SOD and GSH expression, and ameliorate the pathological changes of ferroptosis, the mechanism of which is related to the Nrf2/GPX4 signaling pathway.
10.Acute Inflammatory Pain Induces Sex-different Brain Alpha Activity in Anesthetized Rats Through Optically Pumped Magnetometer Magnetoencephalography
Meng-Meng MIAO ; Yu-Xuan REN ; Wen-Wei WU ; Yu ZHANG ; Chen PAN ; Xiang-Hong LIN ; Hui-Dan LIN ; Xiao-Wei CHEN
Progress in Biochemistry and Biophysics 2025;52(1):244-257
ObjectiveMagnetoencephalography (MEG), a non-invasive neuroimaging technique, meticulously captures the magnetic fields emanating from brain electrical activity. Compared with MEG based on superconducting quantum interference devices (SQUID), MEG based on optically pump magnetometer (OPM) has the advantages of higher sensitivity, better spatial resolution and lower cost. However, most of the current studies are clinical studies, and there is a lack of animal studies on MEG based on OPM technology. Pain, a multifaceted sensory and emotional phenomenon, induces intricate alterations in brain activity, exhibiting notable sex differences. Despite clinical revelations of pain-related neuronal activity through MEG, specific properties remain elusive, and comprehensive laboratory studies on pain-associated brain activity alterations are lacking. The aim of this study was to investigate the effects of inflammatory pain (induced by Complete Freund’s Adjuvant (CFA)) on brain activity in a rat model using the MEG technique, to analysis changes in brain activity during pain perception, and to explore sex differences in pain-related MEG signaling. MethodsThis study utilized adult male and female Sprague-Dawley rats. Inflammatory pain was induced via intraplantar injection of CFA (100 μl, 50% in saline) in the left hind paw, with control groups receiving saline. Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection. For MEG recording, anesthetized rats had an OPM positioned on their head within a magnetic shield, undergoing two 15-minute sessions: a 5-minute baseline followed by a 10-minute mechanical stimulation phase. Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms, generating spectrograms focused on the 4-30 Hz frequency range. ResultsMEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared, before and after saline/CFA injections. Mechanical stimulation elevated alpha activity in both male and female rats pre- and post-saline/CFA injections. Saline/CFA injections augmented average power in both sexes compared to pre-injection states. Remarkably, female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states. Furthermore, despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment, female rats displayed higher average power than males in the resting state after CFA injection. ConclusionThese results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts. Our study exhibits sex differences in alpha activities following CFA injection, highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state. Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals. In addition, the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences.

Result Analysis
Print
Save
E-mail