1.Effects of wogonin on joint inflammation in collagen-induced arthritis rats via the endoplasmic reticulum stress pathway
Yuru WANG ; Siyuan LI ; Ye XU ; Yumeng ZHANG ; Yang LIU ; Huiqin HAO
Chinese Journal of Tissue Engineering Research 2025;29(5):1026-1035
BACKGROUND:Rheumatoid arthritis is an inflammatory disease.Many studies have shown that wogonin has a good anti-inflammatory effect on rheumatoid arthritis,but its exact efficacy and specific mechanism of action remain to be clarified. OBJECTIVE:To investigate the mechanism of wogonin ameliorating joint inflammation by regulating endoplasmic reticulum stress pathway in rats with collagen-induced arthritis. METHODS:(1)At the animal level:Female Wistar rats were divided into healthy control group,arthritis model group and wogonin treatment group.Rat models of arthritis in the latter two groups were established by subcutaneous injection of bovine type Ⅱ collagen and adjuvant.In the wogonin group,wogonin was given by gavage for 28 consecutive days after modeling.During this period,the rats in each group were weighed,and arthritis score and ankle swelling were measured every 7 days.After the experiment,the pathological changes of the joint were observed,the mRNA and protein levels of endoplasmic reticulum stress pathway GRP78 and CHOP were detected by qRT-PCR,western blot,and immunohistochemistry.(2)At the cellular level,cell counting kit-8 was used to detect the cytotoxic effect of wogonin on fibroblast-like synoviocytes from rats with collagen-induced arthritis.The fibroblast-like synoviocytes induced by thapsigargin were treated with different concentrations of wogonin.The levels of interleukin-1β and tumor necrosis factor-α in the cell supernatant were detected by ELISA,and the intracellular reactive oxygen species in each group were determined by DCFH-DA probe method.The mRNA and protein levels of GRP78,IRE1α,XBP1s and CHOP were detected by qRT-PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the healthy control group,arthritis index score and ankle swelling degree in the arthritis model group were increased(P<0.01),synovial hyperplasia,inflammatory cell infiltration,cartilage destruction and bone erosion were observed in pathological sections,and the mRNA and protein expressions of GRP78 and CHOP in the ankle were significantly increased(P<0.01),which were mainly located in synovial tissue and articular surface.Compared with the arthritis model group,the arthritis index score and ankle swelling degree in the wogonin treatment group were decreased(P<0.05),synovial hyperplasia and the number of inflammatory cells were decreased,cartilage destruction and bone erosion were alleviated,the mRNA and protein expression levels of GRP78 and CHOP in the ankle were decreased(P<0.05),particularly in synovial tissue and on the articular surface.There was no significant difference in body mass among the three groups(P>0.05).In the cell experiment,200 μmol/L wogonin significantly reduced the survival rate of fibroblast-like synoviocytes(P<0.01).Compared with the blank control group,the levels of interleukin-1β,tumor necrosis factor-α,content of reactive oxygen species,and mRNA and protein expression of GRP78,IRE1α,XBP1s,and CHOP in the thapsigargin group were significantly increased(P<0.05);compared with the thapsigargin group,50 and 100 μmol/L wogonin significantly reduced the levels of interleukin-1β and tumor necrosis factor-α in the cell supernatant(P<0.05,P<0.01),and 100 μmol/L wogonin significantly reduced the content of reactive oxygen species(P<0.01)and down-regulated the mRNA and protein expression levels of GRP78,IRE1α,XBP1s and CHOP(all P<0.05).These results suggest that wogonin can effectively alleviate joint inflammatory responses in rats with collagen-induced arthritis,and the endoplasmic reticulum stress pathway may be the key target of its intervention.
2.Gut microbiota and osteoporotic fractures
Wensheng ZHAO ; Xiaolin LI ; Changhua PENG ; Jia DENG ; Hao SHENG ; Hongwei CHEN ; Chaoju ZHANG ; Chuan HE
Chinese Journal of Tissue Engineering Research 2025;29(6):1296-1304
BACKGROUND:Osteoporotic fracture is the most serious complication of osteoporosis.Previous studies have demonstrated that gut microbiota has a regulatory effect on skeletal tissue and that gut microbiota has an important relationship with osteoporotic fracture,but the causal relationship between the two is unclear. OBJECTIVE:To explore the causal relationship between gut microbiota and osteoporotic fractures using Mendelian randomization method. METHODS:The genome-wide association study(GWAS)datasets of gut microbiota and osteoporotic fracture were obtained from the IEU Open GWAS database and the Finnish database R9,respectively.Using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,Mendelian randomization analyses with random-effects inverse variance weighted,MR-Egger regression,weighted median,simple model,and weighted model methods were performed to assess whether there is a causal relationship between gut microbiota and osteoporotic fracture.Sensitivity analyses were performed to test the reliability and robustness of the results.Reverse Mendelian randomization analyses were performed to further validate the causal relationship identified in the forward Mendelian randomization analyses. RESULTS AND CONCLUSION:The results of this Mendelian randomization analysis indicated a causal relationship between gut microbiota and osteoporotic fracture.Elevated abundance of Actinomycetales[odds ratio(OR)=1.562,95%confidence interval(CI):1.027-2.375,P=0.037),Actinomycetaceae(OR=1.561,95%CI:1.027-2.374,P=0.037),Actinomyces(OR=1.544,95%CI:1.130-2.110,P=0.006),Butyricicoccus(OR=1.781,95%CI:1.194-2.657,P=0.005),Coprococcus 2(OR=1.550,95%CI:1.068-2.251,P=0.021),Family ⅩⅢ UCG-001(OR=1.473,95%CI:1.001-2.168,P=0.049),Methanobrevibacter(OR=1.274,95%CI:1.001-1.621,P=0.049),and Roseburia(OR=1.429,95%CI:1.015-2.013,P=0.041)would increase the risk of osteoporotic fractures in patients.Elevated abundance of Bacteroidia(OR=0.660,95%CI:0.455-0.959,P=0.029),Bacteroidales(OR=0.660,95%CI:0.455-0.959,P=0.029),Christensenellacea(OR=0.725,95%CI:0.529-0.995,P=0.047),Ruminococcaceae(OR=0.643,95%CI:0.443-0.933,P=0.020),Enterorhabdus(OR=0.558,95%CI:0.395-0.788,P=0.001),Eubacterium rectale group(OR=0.631,95%CI:0.435-0.916,P=0.016),Lachnospiraceae UCG008(OR=0.738,95%CI:0.546-0.998,P=0.048),and Ruminiclostridium 9(OR=0.492,95%CI:0.324-0.746,P=0.001)would reduce the risk of osteoporotic fractures in patients.We identified 16 gut microbiota associated with osteoporotic fracture by the Mendelian randomization method.That is,using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,eight gut microbiota showed positive causal associations with osteoporotic fracture and another eight gut microbiota showed negative causal associations with osteoporotic fracture.The results of this study not only identify new biomarkers for the early prediction of osteoporotic fracture and potential therapeutic targets in clinical practice,but also provide an experimental basis and theoretical basis for the study of improving the occurrence and prognosis of osteoporotic fracture through gut microbiota in bone tissue engineering.
3.Generalized equation estimation of the therapeutic effect of floating needle therapy combined with acupoint embedding on different stages of human knee osteoarthritis
Peiguang WANG ; Xiaowen ZHANG ; Meisi MAI ; Luqian LI ; Hao HUANG
Chinese Journal of Tissue Engineering Research 2025;29(8):1565-1571
BACKGROUND:Acupoint embedding and floating needle therapy are two methods for the treatment of knee osteoarthritis,but there are few reports on the combined treatment of the two methods. OBJECTIVE:To investigate the therapeutic effect of acupoint embedding combined with floating needle therapy on different stages of knee osteoarthritis using generalized estimating equations. METHODS:A total of 436 patients with knee osteoarthritis admitted to Dongguan Hospital of Traditional Chinese Medicine from February 2019 to February 2023 were selected as the research subjects.All patients were randomly divided into a control group with floating needle therapy(n=218)and an observation group with acupoint embedding method combined with floating needle therapy(n=218).Staging was performed according to the K-L staging method.In the control group,there were 57 cases in stage Ⅰ,62 in stage Ⅱ,49 in phase Ⅲ,and 50 in stage Ⅳ,while in the observation group,there were 48 cases in stage Ⅰ,66 in stage Ⅱ,63 in phase Ⅲ,and 41 in stage Ⅳ.The levels of indexes and clinical efficacy were compared between groups before and after treatment.Generalized estimating equation model was used to analyze the influencing factors of clinical efficacy and the interaction effect of different time points,different methods and different stages on therapeutic efficacy. RESULTS AND CONCLUSION:There was no significant difference in baseline data between the observation group and the control group,as well as between the patients of different stages(P>0.05).After treatment,the cure rate of stage Ⅰ patients was the highest after treatment,and the total improvement rate in the observation group was significantly higher than that in the control group.There were significant differences in the cure rate among different stages in each group(P<0.05).After treatment,all indicators in the two groups were significantly decreased.In the control group,there were significant differences in various indicators of patients at different stages after 4 weeks of treatment(P<0.05).In the observation group,after 2 weeks of treatment,there were significant differences in various indicators of patients at different stages(P<0.05),and all the indexes in the observation were lower than those in the control group after 4 weeks of treatment(P<0.05)and the therapeutic effect in the observation group was better than that in the control group.Generalized estimating equation model analysis showed that trauma history,interleukin-6 level,treatment method,treatment time and K-L stage all significantly affected the clinical efficacy in patients.In the interaction effect analysis,after 2 weeks of treatment,there was a significant difference in the visual analogue scale score between the two groups in stages Ⅲ and Ⅳ(P<0.05).After 4 weeks of treatment,there was a significant difference in the visual analogue scale score between the two groups in stages Ⅱ,Ⅲ,and Ⅳ(P<0.05).To conclude,acupoint embedding combined with floating needle therapy is superior to floating needle therapy alone in the treatment of different stages of knee osteoarthritis.Trauma history,interleukin-6 level,treatment method,treatment time and K-L stage significantly influence the therapeutic effect.
4.Advances in the Application of Repetitive Transcranial Magnetic Stimulation for Acute and Maintenance Treatment of Major Depressive Disorder
Medical Journal of Peking Union Medical College Hospital 2025;16(2):321-329
Major depressive disorder (MDD) is a prevalent psychiatric condition characterized by high rates of prevalence and recurrence. Repetitive transcranial magnetic stimulation (rTMS) has been widely utilized in the acute phase treatment of MDD and has shown potential in maintenance therapy. However, the factors influencing the efficacy of rTMS during the acute phase and the sustainability of its long-term therapeutic effects remain incompletely understood. Additionally, a consensus on the optimal maintenance treatment protocol has yet to be established. This article reviews recent evidence on the application of rTMS in both acute and maintenance treatment of MDD, aiming to summarize current research progress and provide insights for the further promotion and application of rTMS in clinical practice.
5.Application and progress of artificial intelligence in the analysis of retinal vascular parameters
Zhaoyang ZHAO ; Huilin LI ; Yanfeng SHANG ; Sisi MENG ; Shaofeng HAO
International Eye Science 2025;25(5):787-791
This review summarizes the applications and advancements of artificial intelligence(AI)in the analysis of retinal vascular parameters. Retinal vascular parameters, including vessel diameter, fractal dimension, vascular tortuosity, branching angles, and vessel density, are important indicators for assessing changes in the retinal vascular network structure. These parameters are not only related to various ophthalmic diseases but also reflect the conditions of systemic diseases such as diabetes and Alzheimer's disease. This article provides a detailed discussion on the advantages of AI technology in the automated identification and quantification of retinal vascular parameters, particularly in improving measurement efficiency and accuracy, and enabling the early detection and monitoring of various diseases. Additionally, the challenges faced by AI in the analysis of retinal vascular parameters were discussed, such as data standardization and insufficient sample diversity, and proposes directions for future research. By thoroughly analyzing the application of AI in retinal vascular parameter analysis, this article aims to offer new perspectives and methods for clinical diagnosis and early intervention of diseases, holding significant clinical significance and application prospects.
6.Inhibition of HDAC3 Promotes Psoriasis Development in Mice Through Regulating Th17
Fan XU ; Xin-Rui ZHANG ; Yang-Chen XIA ; Wen-Ting LI ; Hao CHEN ; An-Qi QIN ; Ai-Hong ZHANG ; Yi-Ran ZHU ; Feng TIAN ; Quan-Hui ZHENG
Progress in Biochemistry and Biophysics 2025;52(4):1008-1017
ObjectiveTo investigate the influence of histone deacetylase 3 (HDAC3) on the occurrence, development of psoriasis-like inflammation in mice, and the relative immune mechanisms. MethodsHealthy C57BL/6 mice aged 6-8 weeks were selected and randomly divided into 3 groups: control group (Control), psoriasis model group (IMQ), and HDAC3 inhibitor RGFP966-treated psoriasis model group (IMQ+RGFP966). One day prior to the experiment, the back hair of the mice was shaved. After a one-day stabilization period, the mice in Control group was treated with an equal amount of vaseline, while the mice in IMQ group was treated with imiquimod (62.5 mg/d) applied topically on the back to establish a psoriasis-like inflammation model. The mice in IMQ+RGFP966 group received intervention with a high dose of the HDAC3-selective inhibitor RGFP966 (30 mg/kg) based on the psoriasis-like model. All groups were treated continuously for 5 d, during which psoriasis-like inflammation symptoms (scaling, erythema, skin thickness), body weight, and mental status were observed and recorded, with photographs taken for documentation. After euthanasia, hematoxylin-eosin (HE) staining was used to assess the effect of RGFP966 on the skin tissue structure of the mice, and skin thickness was measured. The mRNA and protein expression levels of HDAC3 in skin tissues were detected using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB), respectively. Flow cytometry was employed to analyze neutrophils in peripheral blood and lymph nodes, CD4+ T lymphocytes, CD8+ T lymphocytes in peripheral blood, and IL-17A secretion by peripheral blood CD4+ T lymphocytes. Additionally, spleen CD4+ T lymphocyte expression of HDAC3, CCR6, CCR8, and IL-17A secretion levels were analyzed. Immunohistochemistry was used to detect the localization and expression levels of HDAC3, IL-17A, and IL-10 in skin tissues. ResultsCompared with the Control group, the IMQ group exhibited significant psoriasis-like inflammation, characterized by erythema, scaling, and skin wrinkling. Compared with the IMQ group, RGFP966 exacerbated psoriasis-like inflammatory symptoms, leading to increased hyperkeratosis. The psoriasis area and severity index (PASI) skin symptom scores were higher in the IMQ group than those in the Control group, and the scores were further elevated in the IMQ+RGFP966 group compared to the IMQ group. Skin thickness measurements showed a trend of IMQ+RGFP966>IMQ>Control. The numbers of neutrophils in the blood and lymph nodes increased sequentially in the Control, IMQ, and IMQ+RGFP966 groups, with a similar trend observed for CD4+ and CD8+ T lymphocytes in the blood. In skin tissues, compared with the Control group, the mRNA and protein levels of HDAC3 decreased in the IMQ group, but RGFP966 did not further reduce these expressions. HDAC3 was primarily located in the nucleus. Compared with the Control group, the nuclear HDAC3 content decreased in the skin tissues of the IMQ group, and RGFP966 further reduced nuclear HDAC3. Compared with the Control and IMQ groups, RGFP966 treatment decreased HDAC3 expression in splenic CD4+ and CD8+ T cells. RGFP966 treatment increased the expression of CCR6 and CCR8 in splenic CD4+ T cells and enhanced IL-17A secretion by peripheral blood and splenic CD4+ T lymphocytes. Additionally, compared with the IMQ group, RGFP966 reduced IL-10 protein levels and upregulated IL-17A expression in skin tissues. ConclusionRGFP966 exacerbates psoriatic-like inflammatory responses by inhibiting HDAC3, increasing the secretion of the cytokine IL-17A, and upregulating the expression of chemokines CCR8 and CCR6.
7.Analysis of detection of repeat blood donors with unqualified alanine aminotransferase
Zijian ZENG ; Fenfang LIAO ; Junmou XIE ; Zhiting WAN ; Rongsong DU ; Zhongping LI ; Haojian LIANG ; Shijie LI ; Yanli JI ; Huaqin LIANG ; Hao WANG
Chinese Journal of Blood Transfusion 2025;38(4):482-487
[Objective] To retrospectively analyze the detection results of alanine aminotransferase (ALT) unqualified repeat blood donors in Guangzhou, so as to provide evidence for further expanding the repeat blood donor pool, reducing the rate of blood discarding and improving the qualified rate of blood test. [Methods] Blood donors with unqualified ALT in Guangzhou Blood Center from January 2018 to April 2024 were selected as the research objects. The past blood donation and population characteristics were analyzed according to the number of blood donations and ALT unqualified times. [Results] Among repeat blood donors with previous ALT disqualification, 99.5% to 99.7% did not have reactive markers for transfusion-transmitted diseases (TTD), which was higher than the rate among first-time blood donors with unqualified ALT (95.8%) (P<0.05). The rate of single-item ALT disqualification in repeat blood donors was higher in males than in females (P<0.05); it also varied by age (18-25 years > 26-35 years > 36-45 years > over 45 years) (P<0.05); and by quarter (third and fourth quarters > first and second quarters) (P<0.05). The ALT unqualified rate was significantly higher whole blood donors than that of platelet donors and returning blood donors (P<0.05). The overall ALT level (51.0 U/L), individual ALT level (56.0 U/L) and individual ALT unqualified rate (66.7%) of repeat blood donors with multiple ALT disqualifications were higher than those of repeat blood donors with single-item ALT disqualifications (26.0 U/L, 38.5 U/L, and 33.3%, respectively) (P<0.05). Moreover, as the number of ALT disqualifications increased, the overall level of ALT in repeat blood donors also increased (P<0.05), and the average level of individual ALT and individual ALT unqualified ratio tended to increase. Repeat blood donors with frequent ALT disqualifications had higher ALT levels (69.0 U/L). [Conclusion] The ALT unqualified rates of repeat blood donors were mostly non-specific elevation without TTD. Repeat blood donors with multiple ALT disqualifications tend to have continuous high ALT. Moreover, and with the increase of ALT disqualifications times, the overall ALT levels the average individual ALT levels and individual ALT unqualified rates showed an increasing trend.
8.Research the effect of 4℃ refrigerated stored apheresis platelets based on platelet metabolomics
Xiaoye XIA ; Xuejing LI ; Aihua SU ; Xiao HAO ; Hongyan YE
Chinese Journal of Blood Transfusion 2025;38(4):514-521
[Objective] To investigate the differences in metabolomics between apheresis platelets stored at 4℃ and at 22℃ with agitation, aiming to provide a theoretical basis for the cold storage of apheresis platelets. [Methods] Samples were collected at four time points (d1, d5, d10, d15) for platelets stored at 4℃ (experimental group) and two time points (d1, d5) for platelets stored at 22℃ with agitation (control group). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology was used to detect changes in platelet metabolome levels under different storage conditions. Platelet functional activity was assessed by thromboelastography (TEG) for maximum amplitude (MA) values and flow cytometry for CD62P activation rates. [Results] Metabolites in the glycolytic pathway, key metabolites in the tricarboxylic acid cycle (citrate, α-ketoglutarate), metabolites in the purine metabolism pathway (adenine, inosine monophosphate, guanine, etc.) and amino acid metabolites significantly decreased by d5 in the control group, whereas they remained stable in the experimental group. The content of fatty acid metabolites, such as prostaglandin G2, 13(S)-HOTrE, and linoleic acid, significantly increased in the control group. Statistically significant differences in MA values were observed between the two groups at d1 and d5 (P<0.05). However, in the experimental group, as the storage time extended, the MA values at d10 and d15 showed no significant difference compared to the control group at d5 (P>0.05). The CD62P activation rate between the two groups was statistically significant (P<0.05). Additionally, the CD62P activation rate of platelets in the 22℃ group increased rapidly from d1, while it rose gradually in the 4 ℃ group. [Conclusion] Platelets stored at 4 ℃ exhibit more stable metabolic activity and slower functional deterioration, which is beneficial for extending the effective storage period of platelets.
9.Analysis of clinical characteristics and diagnostic prediction of Qi deficiency and blood stasis syndrome in acute ischemic stroke
Hao XU ; Xu ZHU ; Bo LI ; Xiaodan LIU ; Xihui PAN ; Changqing DENG
Digital Chinese Medicine 2025;8(1):111-122
[Objective] :
To explore the clinical characteristics and methods for syndrome differentiation prediction, as well as to construct a predictive model for Qi deficiency and blood stasis syndrome in patients with acute ischemic stroke (AIS).
[Methods] :
This study employed a retrospective case-control design to analyze patients with AIS who received inpatient treatment at the Neurology Department of The First Hospital of Hunan University of Chinese Medicine from January 1, 2013 to December 31, 2022. AIS patients meeting the diagnostic criteria for Qi deficiency and blood stasis syndrome were stratified into case group, while those without Qi deficiency and blood stasis syndrome were stratified into control group. The demographic characteristics (age and gender), clinical parameters [time from onset to admission, National Institutes of Health Stroke Scale (NIHSS) score, and blood pressure], past medical history, traditional Chinese medicine (TCM) diagnostic characteristics (tongue and pulse), neurological symptoms and signs, imaging findings [magnetic resonance imaging-diffusion weighted imaging (MRI-DWI)], and biochemical indicators of the two groups were collected and compared. The indicators with statistical difference (P < 0.05) in univariate analysis were included in multivariate logistic regression analysis to evaluate their predictive value for the diagnosis of Qi deficiency and blood stasis syndrome, and the predictive model was constructed by receiver operating characteristic (ROC) curve analysis.
[Results] :
The study included 1 035 AIS patients, with 404 cases in case group and 631 cases in control group. Compared with control group, patients in case group were significantly older, had extended onset-to-admission time, lower diastolic blood pressure, and lower NIHSS scores (P < 0.05). Case group showed lower incidence of hypertension history (P < 0.05). Regarding tongue and pulse characteristics, pale and dark tongue colors, white tongue coating, fine pulse, astringent pulse, and sinking pulse were more common in case group. Imaging examinations demonstrated higher proportions of centrum semiovale infarction, cerebral atrophy, and vertebral artery stenosis in case group (P < 0.05). Among biochemical indicators, case group showed higher proportions of elevated fasting blood glucose and glycated hemoglobin (HbA1c), while lower proportions of elevated white blood cell count, reduced hemoglobin, and reduced high-density lipoprotein cholesterol (HDL-C) (P < 0.05). Multivariate logistic regression analysis identified significant predictors for Qi deficiency and blood stasis syndrome including: fine pulse [odds ratio (OR) = 4.38], astringent pulse (OR = 3.67), superficial sensory abnormalities (OR = 1.86), centrum semiovale infarction (OR = 1.57), cerebral atrophy (OR = 1.55), vertebral artery stenosis (OR = 1.62), and elevated HbA1c (OR = 3.52). The ROC curve analysis of the comprehensive prediction model yielded an area under the curve (AUC) of 0.878 [95% confidence interval (CI) = 0.855 – 0.900].
[Conclusion]
This study finds out that Qi deficiency and blood stasis syndrome represents one of the primary types of AIS. Fine pulse, astringent pulse, superficial sensory abnormalities, centrum semiovale infarction, cerebral atrophy, vertebral artery stenosis, elevated blood glucose, elevated HbA1c, pale and dark tongue colors, and white tongue coating are key objective diagnostic indicators for the syndrome differentiation of AIS with Qi deficiency and blood stasis syndrome. Based on these indicators, a syndrome differentiation prediction model has been developed, offering a more objective basis for clinical diagnosis, and help to rapidly identify this syndrome in clinical practice and reduce misdiagnosis and missed diagnosis.
10.In situ Analytical Techniques for Membrane Protein Interactions
Zi-Yuan KANG ; Tong YU ; Chao LI ; Xue-Hua ZHANG ; Jun-Hui GUO ; Qi-Chang LI ; Jing-Xing GUO ; Hao XIE
Progress in Biochemistry and Biophysics 2025;52(5):1206-1218
Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.

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