1.Current Status,Strategies and Prospects of Traditional Chinese Medicine Diagnosis and Treatment for Irritable Bowel Syndrome
Yandong WEN ; Zhi YANG ; Shaogang HUANG ; Zhongyu LI ; Xiangxue MA ; Qing XU ; Liqing DU ; Bochao YUAN ; Yibing TIAN ; Wentong GE ; Xiaofan ZHAO ; Chang LIU ; Xudong TANG
Journal of Traditional Chinese Medicine 2026;67(4):404-409
Irritable bowel syndrome (IBS) is a functional bowel disorder characterized primarily by abdominal pain and altered defecation habits. In recent years, traditional Chinese medicine (TCM) has made progress in multiple aspects of IBS research and treatment, including syndrome distribution, development of TCM formulas, clinical efficacy evaluation, external therapies, and psychosocial regulation. However, it still faces challenges such as over-reliance on symptomatic manifestations rather than biomarkers for diagnostic criteria, and the lack of high-quality evidence-based data supporting the efficacy of TCM formulas in treating IBS. This paper proposed that TCM diagnosis and treatment of IBS should adhere to the strategy of integrating the holistic concept with syndrome differentiation and treatment, combining TCM external therapies such as acupuncture, moxibustion and acupoint application), and emphasizing individualized diagnosis and treatment for psychosomatic abnormalities. Future research should integrate multi-omics technologies, artificial intelligence and other methods to deepen the understanding of the pathogenesis of IBS and the mechanisms of TCM formulas, so as to promote the standardization and internationalization of TCM in the diagnosis and treatment of IBS.
2.The Regulatory Effects and Mechanisms of Piezo1 Channel on Chondrocytes and Bone Metabolic Dysregulation in Osteoarthritis
Yan LI ; Tao LIU ; Yu-Biao GU ; Hui-Qing TIAN ; Lei ZHANG ; Bi-Hui BAI ; Zhi-Jun HE ; Wen CHEN ; Jin-Peng LI ; Fei LI
Progress in Biochemistry and Biophysics 2026;53(3):564-576
Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca2+, K+, and Na+, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca2+ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca2+ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca2+ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.
3.The Dual Role of p21 in Hormone-related Cancers and Its Therapeutic Implications
Jia-Wen LI ; Yang CHEN ; Jia-Qi WANG ; Yu-Kai MA ; Zhi-Yi GUO
Progress in Biochemistry and Biophysics 2026;53(3):593-608
p21 (encoded by the CDKN1A gene) is a critical cell cycle regulatory protein endowed with versatile biological functions. In various sex hormone-related cancers, p21 exhibits a paradoxical dual role, capable of both inhibiting tumorigenesis and promoting cancer progression, exerting dual, often opposing, effects on cellular fate that are dictated by the specific context. The clinical targeting of p21 remains elusive, largely due to its functionally pleiotropic and context-dependent nature within intricate regulatory networks. During the initial, hormone-dependent phase of cancers like breast and prostate cancer, p21 expression and activity are largely governed by the transcriptional programs of estrogen or androgen receptor signaling. This hormonal regulation contributes to the control of tumor cell proliferation and underpins the initial efficacy of endocrine therapies. In contrast, as these diseases advance to late stages or evolve into non-hormone-dependent subtypes—exemplified by castration-resistant prostate cancer (CRPC) and specific forms of triple-negative breast cancer (TNBC)—these conventional hormonal control mechanisms often become dysfunctional or are entirely bypassed. This fundamental transition creates a critical therapeutic void, highlighting the urgent need to identify and exploit alternative molecular pathways to effectively target p21’s function. Promising strategies may include the precise modulation of its upstream transcriptional regulators, downstream effector proteins, or the intersecting parallel signaling networks that critically influence its activity. This review provides a systematic synthesis of the intricate and interconnected mechanisms that underpin the dual effects of p21 in sex hormone-related tumors. These mechanisms are categorized into three core, interrelated functional domains. (1) cell cycle regulation: p21 executes its canonical tumor-suppressive role by binding to and inhibiting cyclin-dependent kinases (CDKs) and by directly interacting with proliferating cell nuclear antigen (PCNA), thereby inducing cell cycle arrest, predominantly at the G1/S checkpoint; (2) apoptosis modulation: p21 exerts a highly context-dependent influence on programmed cell death, functioning either as a pro-apoptotic agent under severe genotoxic stress or as a pro-survival factor by inhibiting apoptosis through interactions with proteins like Bcl-2; (3) hormonal and signaling crosstalk: p21 is an integral node within broader cellular networks, engaging in direct physical interactions with hormone receptors(e.g., AR, ER) and participating in complex feedback loops with key oncogenic pathways, including PI3K/AKT, MAPK/ERK, and p53. Critically, the role of p21 is not static but highly dynamic. It can undergo a functional switch from tumor-suppressive to tumor-promoting in response to therapeutic pressures, metabolic alterations, or evolving tumor microenvironment cues. These adaptive shifts are frequently implicated in the development of therapy resistance and disease recurrence, particularly in advanced, hormone-resistant cancers. By synthesizing these insights, this review aims to establish a coherent theoretical framework to guide the future development of novel therapeutic strategies that target the p21 pathway. It underscores the necessity of moving beyond a simplistic, binary view of p21 and emphasizes the forthcoming challenges, such as the discovery of reliable biomarkers to predict its functional state and the rational design of context-specific pharmacological modulators to selectively harness its therapeutic potential.
4.Discriminating Tumor Deposits From Metastatic Lymph Nodes in Rectal Cancer: A Pilot Study Utilizing Dynamic Contrast-Enhanced MRI
Xue-han WU ; Yu-tao QUE ; Xin-yue YANG ; Zi-qiang WEN ; Yu-ru MA ; Zhi-wen ZHANG ; Quan-meng LIU ; Wen-jie FAN ; Li DING ; Yue-jiao LANG ; Yun-zhu WU ; Jian-peng YUAN ; Shen-ping YU ; Yi-yan LIU ; Yan CHEN
Korean Journal of Radiology 2025;26(5):400-410
Objective:
To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer.
Materials and Methods:
A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs.
Results:
All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027).
Conclusion
The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.
5.Application scenarios of rare and endangered Chinese medicinal materials and their substitutes.
Wen-Ting HU ; Xiao-Bo ZHANG ; Yi-Jing ZHANG ; Zhi-Yong LI ; Lan-Ping GUO ; Lu-Qi HUANG
China Journal of Chinese Materia Medica 2025;50(10):2640-2647
Traditional Chinese medicine(TCM) resources are an important foundation for the theory and practice of TCM. Rare and endangered TCM, as a significant component of these resources, plays an essential role. Conducting research on substitutes for rare and endangered TCM resources is of great significance for alleviating resource shortages, promoting the sustainable utilization of TCM, and advancing TCM modernization. This paper reviews the conservation achievements of rare and endangered Chinese medicinal materials in China and organizes the substitution methods for these materials. Currently, the main substitution approaches include introduction and domestication, tissue culture, varietal replacement, and artificial synthesis. Furthermore, this paper proposes the following approaches for researching the application scenarios of rare and endangered medicinal materials, i.e., tracing the historical context of their use to clarify foundational principles; verifying disease classifications to strengthen the clinical application scenarios of these materials; analyzing the evolution patterns of prescription formulations to strengthen the mining of the compatibility application scenarios of rare and endangered medicinal materials; scientifically evaluating to strengthen the application scenario research and development of endangered Chinese patent medicine industry. These efforts aim to promote the scientific substitution and sustainable utilization of rare and endangered medicinal materials and their substitutes.
Drugs, Chinese Herbal/chemistry*
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Humans
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Medicine, Chinese Traditional
;
China
;
Plants, Medicinal/growth & development*
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Endangered Species
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Conservation of Natural Resources
;
Animals
6.Professor YANG Zhong-qi's prescription patterns for hypertension based on latent structure model and association rule analysis.
Hui-Lin LIU ; Shi-Hao NI ; Xiao-Jiao ZHANG ; Wen-Jie LONG ; Xiao-Ming DONG ; Zhi-Ying LIU ; Hui-Li LIAO ; Zhong-Qi YANG
China Journal of Chinese Materia Medica 2025;50(10):2865-2874
Based on latent structure model and association rule analysis, this study investigates the prescription patterns used by professor YANG Zhong-qi in treating hypertension with traditional Chinese medicine(TCM) and infers the associated TCM syndromes, providing a reference for clinical syndrome differentiation and treatment. The observation window spanned from January 8, 2013, to June 26, 2024, during which qualified herbal decoction prescriptions meeting efficacy criteria were extracted from the outpatient medical record system of the First Affiliated Hospital of Guangzhou University of Chinese Medicine and compiled into a standardized database. Statistical analysis of high-frequency herbs included frequency counts and herbal property-channel tropism analysis. Latent structure modeling and association rule analysis were performed using R 4.3.2 and Lantern 5.0 software to identify core herbal combinations and infer TCM syndrome patterns. A total of 2 436 TCM prescriptions were included in the study, involving 263 drugs with a cumulative frequency of 29 783. High-frequency herbs comprised Uncariae Ramulus cum Uncis, Poria, Glycyrrhizae Radix et Rhizoma, Puerariae Lobatae Radix, and Alismatis Rhizoma, predominantly categorized as deficiency-tonifying, heat-clearing, and blood-activating and stasis-resolving herbs. Latent structure analysis identified 18 latent variables, 74 latent classes, 5 comprehensive clustering models, and 15 core herbal combinations, suggesting that the core syndrome clusters include liver Yang hyperactivity pattern, Yin deficiency with Yang hyperactivity pattern, phlegm-stasis intermingling pattern, and liver-kidney insufficiency pattern. Association rule analysis revealed 22 robust association rules. RESULTS:: indicate that hypertension manifests as a deficiency-rooted excess manifestation, significantly associated with functional dysregulation of the liver, lung, spleen-stomach, heart, and kidney. Key pathogenic mechanisms involve liver Yang hyperactivity, phlegm-stasis interaction, and liver-kidney insufficiency. Therapeutic strategies should prioritize liver-calming, spleen-fortifying, and deficiency-tonifying principles, supplemented by dynamic regulation of Qi-blood and Yin-Yang balance according to syndrome evolution, alongside pathogen-eliminating methods such as phlegm-resolving and stasis-dispelling. Synergistic interventions like mind-tranquilizing therapies should be tailored to individual conditions.
Hypertension/drug therapy*
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Drugs, Chinese Herbal/therapeutic use*
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Humans
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Medicine, Chinese Traditional
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Drug Prescriptions
;
Latent Class Analysis
7.Effect of Modified Yiyi Fuzi Baijiang Powder on intestinal mucosal permeability and expression of AQP3, AQP4 in ulcerative colitis rats.
Wen-Xiao LI ; Jiang CHEN ; Zhi-Cheng HE ; Lu-Rong ZHANG ; Guo-Qiang LIANG ; Xing-Xing JIANG ; Yong-Na WEI ; Qin ZHOU
China Journal of Chinese Materia Medica 2025;50(14):3962-3968
This study investigated the therapeutic effects and mechanisms of Modified Yiyi Fuzi Baijiang Powder on ulcerative colitis(UC) in rats from the perspective of dampness. SD rats were randomly allocated into six groups(n=10): control, model, mesalazine, and Modified Yiyi Fuzi Baijiang Powder at low(3.96 g·kg~(-1)·d~(-1)), medium(7.92 g·kg~(-1)·d~(-1)), and high(15.84 g·kg~(-1)·d~(-1)) doses. UC was induced in all groups except the control by administration with 3% dextran sulfate sodium(DSS) solution for 7 days. The disease activity index(DAI) was recorded, and the colon tissue was collected for analysis. Histopathological changes were assessed by hematoxylin-eosin staining. Serum levels of D-lactic acid(D-LA) and diamine oxidase(DAO) were measured by ELISA. Immunohistochemistry and PCR were employed to evaluate the expression of aquaporins(AQP3, AQP4) and tight junction proteins [zonula occludens-1(ZO-1) and occludin] at both protein and mRNA levels. Compared with the control group, the model group showed an increased DAI scores(P<0.05), intestinal mucosal damage, elevated serum levels of DAO and D-LA(P<0.05), and decreased expression of AQP3, AQP4, ZO-1, and occludin(P<0.05). Treatment with Modified Yiyi Fuzi Baijiang Powder reduced the DAI scores(P<0.05), lowered the serum levels of D-LA and DAO(P<0.05), and upregulated the expression of AQP3, AQP4, ZO-1, and occludin at both protein and mRNA levels compared with the model group. These findings suggest that Modified Yiyi Fuzi Baijiang Powder exerts therapeutic effects on UC by reducing the intestinal mucosal permeability, promoting colonic mucosal repair, and regulating abnormal intestinal water metabolism, which may involve the upregulation of AQP3 and AQP4 expression.
Animals
;
Colitis, Ulcerative/genetics*
;
Drugs, Chinese Herbal/administration & dosage*
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Rats, Sprague-Dawley
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Rats
;
Intestinal Mucosa/metabolism*
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Male
;
Aquaporin 3/metabolism*
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Aquaporin 4/metabolism*
;
Permeability/drug effects*
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Humans
;
Powders
;
Intestinal Barrier Function
8.Preparation of baicalin-berberine complex nanocrystal enteric microspheres and pharmacodynamic evaluation of ulcerative colitis treatment in rats.
Xiao-Chao HUANG ; Yi-Wen HU ; Peng-Yu SHEN ; Rui-Hong JIAN ; Dong-Li QI ; Zhi-Dong LIU ; Jia-Xin PI
China Journal of Chinese Materia Medica 2025;50(15):4263-4274
To enhance the therapeutic efficacy of the baicalin-berberine complex(BA-BBR) in the treatment of ulcerative colitis(UC), BA-BBR nanocrystal microspheres(BA-BBR NC MS) were prepared using the dropping method. The microspheres were characterized in terms of morphology, particle size, differential scanning calorimetry(DSC), and powder X-ray diffraction(XRD). The release profiles of BA and BBR from the microspheres were measured, and the drug release mechanism was investigated. A rat model of UC was induced by 5% dextran sodium sulfate(DSS) and treated continuously for 7 days to evaluate the therapeutic effects of different formulations. The results showed that the prepared BA-BBR MS and BA-BBR NC MS were uniform gel spheres with particle sizes of(1.77±0.16) mm and(1.67±0.08) mm, respectively. After drying, the gels collapsed inward and exhibited a rough surface. During the preparation process, the BA-BBR nanocrystals(BA-BBR NC) were uniformly encapsulated within the microspheres. The release profiles of the microspheres followed a first-order kinetic model, and the 12-hour cumulative release of BA and BBR from BA-BBR NC MS was higher than that from BA-BBR MS. Compared with BA-BBR, BA-BBR NC, and BA-BBR MS, BA-BBR NC MS further alleviated UC symptoms in rats, most significantly reducing the levels of TNF-α, IL-1β, IL-6, and MPO, while increasing the level of IL-4 in colon tissues. These results indicate that BA-BBR NC MS, based on a "nano-in-micro" design, can deliver BA-BBR to the intestine and exert significant therapeutic effects in a UC rat model, suggesting it as a promising new strategy for the treatment of UC.
Animals
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Colitis, Ulcerative/metabolism*
;
Rats
;
Nanoparticles/chemistry*
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Microspheres
;
Male
;
Berberine/administration & dosage*
;
Flavonoids/administration & dosage*
;
Rats, Sprague-Dawley
;
Drugs, Chinese Herbal/administration & dosage*
;
Humans
;
Particle Size
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Tumor Necrosis Factor-alpha/immunology*
;
Drug Liberation
;
Drug Compounding
9.Application of Assessment Scales in Palliative Care for Glioma: A Systematic Review.
Zhi-Yuan XIAO ; Tian-Rui YANG ; Ya-Ning CAO ; Wen-Lin CHEN ; Jun-Lin LI ; Ting-Yu LIANG ; Ya-Ning WANG ; Yue-Kun WANG ; Xiao-Peng GUO ; Yi ZHANG ; Yu WANG ; Xiao-Hong NING ; Wen-Bin MA
Chinese Medical Sciences Journal 2025;40(3):211-218
BACKGROUND AND OBJECTIVE: Patients with glioma experience a high symptom burden and have diverse palliative care needs. However, the assessment scales used in palliative care remain non-standardized and highly heterogeneous. To evaluate the application patterns of the current scales used in palliative care for glioma, we aim to identify gaps and assess the need for disease-specific scales in glioma palliative care. METHODS: We conducted a systematic search of five databases including PubMed, Web of Science, Medline, EMBASE, and CINAHL for quantitative studies that reported scale-based assessments in glioma palliative care. We extracted data on scale characteristics, domains, frequency, and psychometric properties. Quality assessments were performed using the Cochrane ROB 2.0 and ROBINS-I tools. RESULTS: Of the 3,405 records initially identified, 72 studies were included. These studies contained 75 distinct scales that were used 193 times. Mood (21.7%), quality of life (24.4%), and supportive care needs (5.2%) assessments were the most frequently assessed items, exceeding half of all scale applications. Among the various assessment dimensions, the Distress Thermometer (DT) was the most frequently used tool for assessing mood, while the Short Form-36 Health Survey Questionnaire (SF-36) was the most frequently used tool for assessing quality of life. The Mini Mental Status Examination (MMSE) was the most common tool for cognitive assessment. Performance status (5.2%) and social support (6.8%) were underrepresented. Only three brain tumor-specific scales were identified. Caregiver-focused scales were limited and predominantly burden-oriented. CONCLUSIONS: There are significant heterogeneity, domain imbalances, and validation gaps in the current use of assessment scales for patients with glioma receiving palliative care. The scale selected for use should be comprehensive and user-friendly.
Humans
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Glioma/psychology*
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Palliative Care/methods*
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Quality of Life
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Psychometrics
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Brain Neoplasms/psychology*
10.Junctophilin-2 MORN-Helix Domain: Structural Basis for Membrane Binding and Hypertrophic Cardiomyopathy-associated Mutations
Jing-Xin WANG ; Zhi-Wei LI ; Wei LIU ; Wen-Qing ZHANG ; Jian-Chao LI
Progress in Biochemistry and Biophysics 2025;52(8):2103-2116
ObjectiveJunctophilin-2 (JPH2) is an essential structural protein that maintains junctional membrane complexes (JMCs) in cardiomyocytes by tethering the plasma membrane to the sarcoplasmic reticulum, thereby facilitating excitation-contraction (E-C) coupling. Mutations in JPH2 have been associated with hypertrophic cardiomyopathy (HCM), but the molecular mechanisms governing its membrane-binding properties and the functional relevance of its membrane occupation and recognition nexus (MORN) repeat motifs remain incompletely understood. This study aimed to elucidate the structural basis of JPH2 membrane association and its implications for HCM pathogenesis. MethodsA recombinant N-terminal fragment of mouse JPH2 (residues1-440), encompassing the MORN repeats and an adjacent helical region, was purified under near-physiological buffer conditions.X-ray crystallography was employed to determine the structure of the JPH2 MORN-Helix domain. Sequence conservation analysis across species and junctophilin isoforms was performed to assess the evolutionary conservation of key structural features. Functional membrane-binding assays were conducted using liposome co-sedimentation and cell-based localization studies in COS7 and HeLa cells. In addition, site-directed mutagenesis targeting positively charged residues and known HCM-associated mutations, including R347C, was used to evaluate their effects on membrane interaction and subcellular localization. ResultsThe crystal structure of the mouse JPH2 MORN-Helix domain was resolved at 2.6 Å, revealing a compact, elongated architecture consisting of multiple tandem MORN motifs arranged in a curved configuration, forming a continuous hydrophobic core stabilized by alternating aromatic residues. A C-terminal α-helix further reinforced structural integrity. Conservation analysis identified the inner groove of the MORN array as a highly conserved surface, suggesting its role as a protein-binding interface. A flexible linker segment enriched in positively charged residues, located adjacent to the MORN motifs, was found to mediate direct electrostatic interactions with negatively charged phospholipid membranes. Functional assays demonstrated that mutation of these basic residues impaired membrane association, while the HCM-linked R347C mutation completely abolished membrane localization in cellular assays, despite preserving the overall MORN-Helix fold in structural modeling. ConclusionThis study provides structural insight into the membrane-binding mechanism of the cardiomyocyte-specific protein JPH2, highlighting the dual roles of its MORN-Helix domain in membrane anchoring and protein interactions. The findings clarify the structural basis for membrane targeting via a positively charged linker and demonstrate that disruption of this interaction—such as that caused by the R347C mutation—likely contributes to HCM pathogenesis. These results not only enhance current understanding of JPH2 function in cardiac E-C coupling but also offer a structural framework for future investigations into the assembly and regulation of JMCs in both physiological and disease contexts.

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