1.Skeleton Binding Protein 1 of Plasmodium berghei Influences Deformability and Cytoskeletal Ultrastructure of Infected Erythrocyte
Xin-Yue GUO ; Huan-Qi ZHAO ; Yan-Xuan ZHONG ; Ru-Meng JIANG ; Yao-Xian LI ; Lei-Ting PAN ; Qian WANG ; Xiao-Yu SHI
Progress in Biochemistry and Biophysics 2026;53(4):1015-1027
ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.
2.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.
3.Analysis of Toxicity Characteristics and Rational Drug Use of Polygoni Multiflori Radix
Qiongyi FU ; Yupu QI ; Yu HUAN ; Yagang SONG ; Xiangxiang WU ; Mingsan MIAO
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):222-231
ObjectivePolygoni Multiflori Radix is a commonly used tonic traditional Chinese medicine (TCM) in clinical practice, but liver injury has often been reported in recent years. Some related preparations containing Polygoni Multiflori Radix have been reported by the National Medical Products Administration many times for the risk of liver injury. This has caused extensive discussion on the potential toxicity of TCM in China and abroad, which has limited the clinical use of Polygoni Multiflori Radix to some extent. To understand the adverse reactions of Polygoni Multiflori Radix, the safe and rational use of Polygoni Multiflori Radix in clinical practice was discussed. MethodsThe pharmacovigilance thought of modern Chinese medicine and the TCM pharmacovigilance system framework of ''identification of poison, use of poison, anti-poison, and detoxification'' were employed to mine the relevant toxicity records, usage and dosage, processing compatibility, and contraindication of taking Polygoni Multiflori Radix in ancient books. The drug safety information of Polygoni Multiflori Radix was summarized by comparing with modern reports. ResultsA total of 74 ancient books related to Polygoni Multiflori Radix were included, suggesting that the toxicity of Polygoni Multiflori Radix was recognized in ancient times. The main chemical components of Polygoni Multiflori Radix had both efficacy and toxicity, and the adverse reactions may be related to long-term use, excessive use, and individual differences. The results showed that the toxic components of Polygoni Multiflori Radix could be reduced by peeling, steaming with black beans, and processing without iron tools. The toxic effects of Polygoni Multiflori Radix could be reduced by the compatibility of Polygoni Multiflori Radix with Poria, Psoraleae Fructus, and Cistanches Herba. ConclusionReasonable dosage, standard processing, correct compatibility, and syndrome differentiation are the key points to standardize the use of Polygoni Multiflori Radix and reduce the incidence of adverse reactions. Clinically, the toxicity classification of TCM should be strengthened, and the susceptible population should be prioritized. The detection indicators and early warning mechanisms should be improved, and precise drug dosage and course of treatment should be guaranteed. These measures can ensure the safe use of Polygoni Multiflori Radix.
4.Analysis of Toxicity Characteristics and Rational Drug Use of Polygoni Multiflori Radix
Qiongyi FU ; Yupu QI ; Yu HUAN ; Yagang SONG ; Xiangxiang WU ; Mingsan MIAO
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):222-231
ObjectivePolygoni Multiflori Radix is a commonly used tonic traditional Chinese medicine (TCM) in clinical practice, but liver injury has often been reported in recent years. Some related preparations containing Polygoni Multiflori Radix have been reported by the National Medical Products Administration many times for the risk of liver injury. This has caused extensive discussion on the potential toxicity of TCM in China and abroad, which has limited the clinical use of Polygoni Multiflori Radix to some extent. To understand the adverse reactions of Polygoni Multiflori Radix, the safe and rational use of Polygoni Multiflori Radix in clinical practice was discussed. MethodsThe pharmacovigilance thought of modern Chinese medicine and the TCM pharmacovigilance system framework of ''identification of poison, use of poison, anti-poison, and detoxification'' were employed to mine the relevant toxicity records, usage and dosage, processing compatibility, and contraindication of taking Polygoni Multiflori Radix in ancient books. The drug safety information of Polygoni Multiflori Radix was summarized by comparing with modern reports. ResultsA total of 74 ancient books related to Polygoni Multiflori Radix were included, suggesting that the toxicity of Polygoni Multiflori Radix was recognized in ancient times. The main chemical components of Polygoni Multiflori Radix had both efficacy and toxicity, and the adverse reactions may be related to long-term use, excessive use, and individual differences. The results showed that the toxic components of Polygoni Multiflori Radix could be reduced by peeling, steaming with black beans, and processing without iron tools. The toxic effects of Polygoni Multiflori Radix could be reduced by the compatibility of Polygoni Multiflori Radix with Poria, Psoraleae Fructus, and Cistanches Herba. ConclusionReasonable dosage, standard processing, correct compatibility, and syndrome differentiation are the key points to standardize the use of Polygoni Multiflori Radix and reduce the incidence of adverse reactions. Clinically, the toxicity classification of TCM should be strengthened, and the susceptible population should be prioritized. The detection indicators and early warning mechanisms should be improved, and precise drug dosage and course of treatment should be guaranteed. These measures can ensure the safe use of Polygoni Multiflori Radix.
5.Traditional Chinese Medicine Intervention in Parkinson's Disease Based on Keap1/Nrf2/ARE Signaling Pathway: A Review
Liuping YUE ; Yongkang SUN ; Fangbiao XU ; Yanbo SONG ; Yijun WU ; Huan YU ; Xinzhi WANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(9):307-317
Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder primarily characterized by motor dysfunction. The main pathological features include the loss of dopaminergic neurons in the substantia nigra, abnormal aggregation of alpha-Synuclein (α-Syn), and the formation of Lewy bodies. However, the exact mechanisms remain unclear. In recent years, the PD incidence has gradually increased, while current treatment methods are limited to symptom alleviation, incapable of halting disease progression, and prone to adverse effects, thus making it urgent to search for medicines effective for PD. Modern research indicates that the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor E2 related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway is closely related to oxidative stress, neuroinflammation, apoptosis, ferroptosis, and mitochondrial dysfunction, playing a crucial role in the pathophysiological development of PD. A large number of studies have further confirmed that traditional Chinese medicine (TCM) can regulate diseases through a holistic view of Syndrome differentiation and microscopic molecular pathways. With unique advantages, such as multiple targets, multiple pathways, and fewer adverse reactions, TCM provides a new strategy for PD treatment. This article elucidates the mechanism of the Keap1/Nrf2/ARE signaling pathway in the occurrence and development of PD, while summarizing the latest research on PD intervention by TCM monomers, active ingredients, and compounds, as well as acupuncture via the precise targeted regulation of the Keap1/Nrf2/ARE pathway, aiming to provide a reference for clinical medicine development to prevent and treat PD.
6.Neuroprotective effect and mechanism of eleutheroside B on Parkinson’s disease model mice by regulating the IKKβ/NF-κB signaling pathway
Xiaoli WANG ; Hua RONG ; Siwen PAN ; Chunlei YU ; Tianjiao XU ; Yu SUN ; Huan CONG ; Yu PANG ; Gang CHEN ; Xiaoming LI
China Pharmacy 2026;37(8):998-1002
OBJECTIVE To investigate the neuroprotective effect and mechanism of eleutheroside B (ELB) on Parkinson’s disease (PD) model mice by regulating the IκB kinase β (IKKβ)/nuclear factor-κB (NF-κB) signaling pathway. METHODS Fifty mice were randomly divided into normal control group, model group, positive control group (selegiline hydrochloride, 10 mg/kg), and ELB low-dose and high-dose groups (80, 160 mg/kg), with 10 mice in each group. Each group was given relevant medicine or normal saline intragastrically for 14 consecutive days. Starting from the 10th day of administration, the model group and all administration groups were intraperitoneally injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) 30 mg/kg, for five consecutive days to establish the chronic PD model. After the last administration for 24 h, six mice were randomly selected from each group to test their behavioral abilities; detect the levels of interleukin-1β (IL-1β), IL-10, tumor necrosis factor-α (TNF-α) in brain tissue and their mRNA expressions were measured, and positive expression of tyrosine hydroxylase (TH), protein expressions of TH, α -synuclein ( α -syn), ionized calcium-binding adaptor molecule 1 (Iba-1), as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in the brain tissue were detected. The ultrastructure of neurons in substantia nigra was observed. RESULTS Compared with the model group, rotarod endurance time and climbing score of each administration group (except for the ELB low-dose group) were increased significantly ( P <0.05), while the levels and mRNA expressions of IL-1β, TNF-α, α -syn, and Iba-1, as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in brain tissue were decreased significantly (except for TNF-α in the ELB low-dose group). Conversely, the level and mRNA expression of IL-10 (except for the ELB low-dose group), TH positive expression and protein expressions were significantly increased ( P <0.05). Typical neurodegenerative pathological changes, such as neuronal karyopyknosis, mitochondrial swelling and vacuolization, and endoplasmic reticulum dilation, all showed varying degrees of improvement. CONCLUSIONS ELB may exert neuroprotective effects by inhibiting the activation of the IKKβ/NF-κB signaling pathway, alleviating inflammatory responses, reducing abnormal α -syn aggregation and neuronal loss, and further improving motor dysfunction in PD mice.
7.Differences in deltamethrin resistance and kdr gene mutation in Culex tritaeniorhynchus population in and outside the Yellow Sea wetland
Xiao-er ZHANG ; Zhi-ming WU ; Ye TIAN ; Qian CUI ; Yu-qian JI ; Huan WANG ; Shu-juan YANG ; Yi-chao ZHAO ; Yu WANG ; Hua-yu YIN ; Yu DING ; Guo-jin YAN ; Min-sen ZHAO ; Shou-gang ZHANG ; Bing-dong SONG ; Hong-na CHEN ; Jian GAO ; Wei-fang YANG ; Yu-fu ZHANG ; Hui LIU ; Hong-liang CHU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):101-107
Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.
8.Whole-process nutritional management and medical resource utilization in hospitalized elderly patients with multimorbidity
Jiaxin YU ; Yiling LI ; Xinyu ZHANG ; Huan ZHU ; Wen HU ; Zhiyong RAO
Journal of Public Health and Preventive Medicine 2026;37(4):76-80
Objective To describe the clinical characteristics and nutritional management status of hospitalized elderly patients with multimorbidity in a tertiary hospital's geriatric center in 2024, and to analyze the correlation between nutritional status and hospitalization outcomes, thereby providing a basis for optimizing nutritional management pathways for this population. Methods A retrospective study was conducted, including 2 937 elderly patients with multimorbidity. Data on general information, clinical indicators, nutritional risk screening and assessment, nutritional therapy, and costs were collected for descriptive analysis. The relationship between nutritional status (based on BMI and serum albumin levels) and hospitalization outcomes was explored. Results The average age of the patients was (77.45±10.70) years, with 57.17% being male. The average number of chronic diseases diagnosed was (11.56±5.08) per patient, and 26.01% were critically ill. The nutritional risk screening rate was 80.40%, with a screening positivity rate of 33.44%. The nutritional assessment rate was 31.63%, and the malnutrition prevalence was 23.08%. The low BMI group had the longest median hospital stay [15 (9.75, 22) days] and the highest hospitalization costs [15 057.2 (8 980.48, 28 160.46) CNY]. Serum albumin levels were negatively correlated with hospital stay duration (rs=-0.276, P< 0.01) and hospitalization costs (rs=-0.276, P<0.01). Conclusion Hospitalized elderly patients with multimorbidity are characterized by multiple comorbidities and high healthcare resource consumption. While the nutritional risk screening rate is relatively high, there remains room for improvement in nutritional assessment and therapy. It is necessary to strengthen standardized management throughout the entire process. Nutritional status is a significant variable affecting hospital stay duration and costs, with poorer nutritional status significantly associated with prolonged hospitalization and higher costs, suggesting that it may be an important factor influencing hospitalization outcomes.
9.Mechanism of Shengxian Yixin Granule (升陷益心颗粒) in the Treatment of Heart Failure with Preserved Ejection Fraction Based on Macrophage-Mediated Inflammatory Response
Zhengwei DONG ; Rui YU ; Qiaozhi LI ; Huan ZHAO ; Jingjing WEI ; Genhao FAN ; Xinlu WANG ; He WANG ; Yongxia WANG ; Mingjun ZHU
Journal of Traditional Chinese Medicine 2026;67(19):2086-2094
ObjectiveTo investigate the effect and mechanism of Shengxian Yixin Granule (升陷益心颗粒, SYG) in treating heart failure with preserved ejection fraction (HFpEF). MethodsExperiment 1: Forty male C57BL/6 mice were randomly divided into control group, model group, low-dose [25 mg/(kg·d)], medium-dose [50 mg/(kg·d)], and high-dose [(75 mg/(kg·d)] SYG groups, with 8 mice per group. Except for the control group, HFpEF was induced by a high-fat diet combined with Nω-nitro-L-arginine methyl ester in drinking water for 16 weeks. After 10 weeks of modeling, treatment groups received corresponding doses of SYG by gavage, while the control group and model group received equal volume of normal saline, for 6 weeks. After 6 weeks of administration, the body weight, blood pressure including systolic blood pressure (SBP) and diastolic blood pressure (DBP), and heart weight-to-tibia length ratio (HW/TL) were recorded. Echocardiography was used to evaluate left ventricular ejection fraction (LVEF) and the ratio of early to late diastolic transmitral flow velocity (E/A). Plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) levels were measured by ELISA. The expression level of brain natriuretic peptide (BNP) in heart tissue was detected by qRT-PCR. Blood lipid levels, including low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and total cholesterol (TC), were determined by a biochemical analyzer. Splenic proportions of M1 macrophages, M2 macrophages, T helper 17 (Th17) cells, and regulatory T (Treg) cells were analyzed by flow cytometry. Experiment 2: RAW 264.7 cells were stimulated with lipopolysaccharide (LPS) to establish an M1 macrophage polarization model, and then treated with SYG-containing serum for 24 h. The cells were divided into four groups, including blank serum group, high-dose SYG-containing serum group, LPS group, and LPS plus high-dose SYG-containing serum group. Combined with asignal transducer and activator of transcription 3 (Stat3) inhibitor for 24 h, the cells were divided into a lipopolysaccharide group, a high-dose SYG-containing serum group, an inhibitor group, and high-dose SYG-containing serum plus inhibitor group. The expression levels of inducible nitric oxide synthase (iNOS) and interleukin-1β (IL-1β) in each group were detected by qRT-PCR. The protein levels of iNOS, IL-1β, Stat3, and phosphorylated Stat3 (p-Stat3) were detected by Western Blotting. ResultsExperiment 1: Compared to the control group, the model group showed significantly decreased E/A ratio, and increased cardiac BNP expression, plasma NT-proBNP,HW/TL ratio, body weight, TC, LDL-C, SBP, and DBP, as well as shortened exhaustion distance and exhaustion time (P<0.05 or P<0.01). Compared to the model group, the E/A ratio increased in the low-, medium-, and high-dose SYG groups; cardiac BNP expression decreased in the low- and high-dose groups, and plasma NT-proBNP levels decreased in the high-dose group; the HW/TL ratio and body weight decreased, while exhaustion distance and exhaustion time increased in the medium- and high-dose groups; TG levels decreased in the low- and medium-dose groups, and LDL-C levels decreased in the medium- and high-dose groups; SBP and DBP decreased in the low-, medium-, and high-dose groups (P<0.05 or P<0.01). Compared to the low-dose SYG group, body weight decreased, and both exhaustion distance and exhaustion time increased in the medium- and high-dose groups (P<0.05 or P<0.01). Compared to the medium-dose SYG group, the exhaustion time increased in the high-dose SYG group (P<0.01). Experiment 2: In the LPS‑induced M1 macrophage polarization model, compared to the blank serum group, the LPS group showed significantly increased mRNA and protein expression of iNOS and IL‑1β, as well as the p‑Stat3/Stat3 ratio (P<0.01). Compared to the LPS group, the high‑dose SYG-containing serum plus LPS group showed significantly decreased mRNA and protein expression of iNOS and IL‑1β, as well as the p‑Stat3/Stat3 ratio (P<0.05 or P<0.01). Compared to the LPS group, the inhibitor group also showed significantly reduced these parameters (P<0.05 or P<0.01). ConclusionSYG can improve cardiac function, ventricular remodeling, exercise capacity, and lipid metabolism in HFpEF mice, while inhibiting inflammatory responses. Its mechanism may be related to the regulation of the Stat3 signaling pathway and inhibition of M1 macrophage polarization.
10.α7 Nicotinic Acetylcholine Receptor: From Structural Mechanisms to Therapeutic Translation
Yu-Han LIU ; Jiao-Feng CHEN ; Hong-Juan WANG ; Huan CHEN ; Hong-Wei HOU
Progress in Biochemistry and Biophysics 2026;53(9):2378-2391
The α7 nicotinic acetylcholine receptor (α7 nAChR) is a ligand-gated ion channel characterized by high Ca2+ permeability, rapid activation, and rapid desensitization. It is widely expressed in the nervous system and various non-neuronal cell types. α7 nAChR is involved in regulating neuronal excitability, synaptic transmission and plasticity, cognitive function, and inflammatory responses. These properties have made α7 nAChR a potential therapeutic target for neuropsychiatric and inflammatory diseases. In recent years, advances in cryo-electron microscopy have provided structural insights into α7 nAChR gating, ligand recognition, allosteric modulation, and allosteric activation. The receptor mainly undergoes transitions among resting, open, and desensitized states. Recent structural studies have further revealed asymmetric conformational changes and multiple intermediate states during receptor activation and recovery from desensitization. Conformational rearrangements in the extracellular domain-transmembrane domain coupling region and the pore-forming M2 helices are closely associated with channel opening and desensitization. However, structural characterization of the α7 nAChR gating cycle still largely depends on pharmacological stabilization. Open-state structures have been resolved in the presence of PNU-120596 or GAT107, whereas a high-resolution structure of the open state induced by acetylcholine alone remains to be determined. These physiological roles underpin the involvement of α7 nAChR in multiple disease processes. In the hippocampus, α7 nAChR regulates local neuronal circuits, theta oscillations, synaptic transmission, and synaptic plasticity, thereby contributing to learning, memory, attention, and other cognitive processes. In macrophages, microglia, and other immune-related cells, α7 nAChR activation regulates inflammatory responses and oxidative stress. These effects involve several signaling pathways, including Janus kinase 2 (JAK2)/STAT3, phosphoinositide 3-kinase (PI3K)/AKT, and NF-κB signaling, as well as regulation of the NLRP3 inflammasome and IL-1β production. Such anti-inflammatory effects may also contribute to α7 nAChR-mediated neuroprotection. Although several compounds targeting α7 nAChR have entered clinical studies, no α7 nAChR-selective drug has been approved for clinical use. Limited clinical translation may be related to rapid receptor desensitization, inconsistent efficacy across clinical studies, insufficient or variable target engagement, patient heterogeneity, and clinical endpoint selection. TC-5619 showed promising effects on cognitive impairment and negative symptoms in an early exploratory study of schizophrenia, but these effects were not confirmed in a subsequent, larger phase II trial. Encenicline (EVP-6124) also showed cognitive improvement in early studies, whereas two global phase III trials in schizophrenia failed to meet their co-primary cognitive and functional endpoints. Pharmacological strategies targeting α7 nAChR have expanded from orthosteric agonists to positive allosteric modulators (PAMs) and allosteric agonist-positive allosteric modulators (ago-PAMs). Orthosteric agonists directly activate the receptor by binding to the orthosteric site, but their effects are limited by rapid receptor desensitization. Type I PAMs mainly enhance agonist-evoked responses with relatively small effects on desensitization, whereas type II PAMs markedly potentiate receptor responses and reduce or delay desensitization. Ago-PAMs such as GAT107 can directly activate α7 nAChR through an allosteric mechanism while also potentiating responses to orthosteric agonists. Together, these findings have broadened the pharmacological approaches to α7 nAChR regulation. In summary, future drug development should focus on precise regulation of α7 nAChR according to receptor structure and disease mechanisms, rather than simply enhancing receptor activation. Further studies are needed to clarify how candidate ligands affect receptor gating, conformational transitions, recovery from desensitization, and downstream signaling. Pharmacological differences between neuronal and non-neuronal α7 nAChRs, between homomeric α7 and heteromeric α7β2 receptors, and between α7 nAChR and other nAChR subtypes also require further investigation. Integrating structure prediction, artificial intelligence-assisted virtual screening, molecular docking, molecular dynamics simulations, and electrophysiological validation may facilitate the discovery and optimization of new α7 nAChR modulators.


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