1.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.
2.Promotion of Angiogenesis by Colorectal Cancer Cell LoVo Derived-exosomes Through Transferring pEGFR
Ya-Jie CHENG ; Xue-Tong ZHOU ; Rui WANG ; Jin FANG
Progress in Biochemistry and Biophysics 2025;52(5):1229-1240
ObjectiveThis study sought to investigate the impact of exosomes derived from LoVo cells (LoVo-Exos) in colorectal cancer (CRC) on tumor angiogenesis, as well as to elucidate the potential molecular mechanisms underlying their pro-angiogenic effects. MethodsLoVo-Exos were isolated via ultracentrifugation, and their internalization into recipient human umbilical vein endothelial cells (HUVECs) was visualized using confocal microscopy. The influence of LoVo-Exos on angiogenesis was assessed through an in vitro tube formation assay. Additionally, the pro-angiogenic effects of LoVo-Exos were evaluated in vivo using a matrix gluing assay in mice. To investigate the molecular mechanisms through which LoVo-Exos facilitate angiogenesis, Western blot analysis was employed to examine the transfer of pEGFR by LoVo-Exos into recipient cells. Both Western blot and ELISA were utilized to assess the expression levels of key signaling proteins within the EGFR-ERK pathway, as well as the expression of downstream angiogenic core molecules. Furthermore, the impact of EGFR knockdown and ERK inhibitor treatment on angiogenesis was evaluated, with subsequent analysis of the expression of downstream angiogenic core molecules following these interventions. ResultsConfocal microscopy demonstrated the internalization of LoVo-Exos into HUVECs. In vitro angiogenesis assays further indicated that LoVo-Exos significantly enhanced the formation of tubular structures in HUVECs. Additionally, macroscopic examination of subcutaneous matrix plug formation in mice revealed a substantial increase in vascular-like structures within the matrix plugs following the administration of LoVo-Exos, compared to the PBS control group. Hematoxylin and eosin (HE) staining revealed the presence of erythrocyte-filled microvessels within the matrix plugs combined with LoVo-Exos. Furthermore, immunohistochemical analysis demonstrated the expression of the endothelial cell marker CD31 in these matrix plugs. The presence of CD31-positive cells in the LoVo-Exos-treated matrix plugs was associated with a significant enhancement in the formation of luminal structures. These findings suggest that LoVo-Exos facilitate the in vivo development of vascular-like structures. Subsequent investigations demonstrated that LoVo-Exos facilitated the delivery of pEGFR to HUVEC, thereby enhancing angiogenesis. Conversely, LoVo-Exos with EGFR knockdown exhibited a diminished capacity to promote angiogenesis, an effect that was further attenuated by the ERK phosphorylation inhibitor U0126. Western blot analysis assessing the activation of the EGFR-ERK signaling pathway in HUVEC indicated that LoVo-Exos augmented angiogenesis through the activation of this pathway. Furthermore, analysis of the impact of LoVo-Exos on the expression of downstream angiogenic core molecules revealed an increase in interleukin-8 (IL-8) secretion in HUVEC. The enhancement observed was diminished in LoVo-Exos following EGFR knockdown, and this reduction was counteracted by the ERK phosphorylation inhibitor U0126. ConclusionThe underlying mechanism may involve the delivery of pEGFR in LoVo-Exos to HUVECs, leading to increased IL-8 secretion via the EGFR-ERK signaling pathway, thereby enhancing the angiogenic potential of HUVECs. This finding may offer new insights into the mechanisms underlying cancer metastasis.
3.Sequencing and analysis of the complete mitochondrial genome of Bulinus globosus
Peijun QIAN ; Mutsaka-Makuvaza MASCELINE JENIPHER ; Chao LÜ ; Yingjun QIAN ; Wenya WANG ; Shenglin CHEN ; Andong XU ; Jingbo XUE ; Jing XU ; Xiaonong ZHOU ; Midzi NICHOLAS ; Shizhu LI
Chinese Journal of Schistosomiasis Control 2025;37(2):116-126
Objective To analyze the structural and phylogenetic characteristics of the mitochondrial genome from Bulinus globosus, so as to provide a theoretical basis for classification and identification of species within the Bulinus genus, and to provide insights into understanding of Bulinus-schistosomes interactions and the mechanisms of parasite transmission. Methods B. globosus samples were collected from the Ruya River basin in Zimbabwe. Mitochondrial DNA was extracted from B. globosus samples and the corresponding libraries were constructed for high-throughput sequencing on the Illumina NovaSeq 6000 platform. After raw sequencing data were subjected to quality control using the fastp software, genome assembly was performed using the A5-miseq and SPAdes tools, and genome annotation was conducted using the MITOS online server. Circular maps and sequence plots of the mitochondrial genome were generated using the CGView and OGDRAW software, and the protein conservation motifs and structures were analyzed using the TBtools software. Base composition and codon usage bias were analyzed and visualized using the software MEGA X and the ggplot2 package in the R software. In addition, a phylogenetic tree was created in the software MEGA X after sequence alignment with the software MAFFT 7, and visualized using the software iTOL. Results The mitochondrial genome of B. globosus was a 13 730 bp double-stranded circular molecule, containing 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes, with a marked AT preference. The mitochondrial genome composition of B. globosus was similar to that of other species within the Bulinus genus. Phylogenetic analysis revealed that the complete mitochondrial genome sequence of B. globosus was clustered with B. truncatus, B. nasutus, and B. ugandae into the same evolutionary clade, and gene superfamily analysis showed that the metabolism-related proteins of B. globosus were highly conserved, notably the cytochrome c oxidase family, which showed a significant consistency. Conclusions This is the first whole mitochondrial genome sequencing to decode the compositional features of the mitochondrial genome of B. globosus from Zimbabwe and its evolutionary relationship within the Bulinus genus, which provides important insights for further understanding of the phylogeny and mitochondrial genome characteristics of the Bulinus genus.
4.Collection, storage and utilization of lung transplant tissue samples
Yixing LI ; Xue SHI ; Hongyi WANG ; Runyi TAO ; Ye SUN ; Ailing SU ; Liyan TONG ; Jinteng FENG ; Yanpeng ZHANG ; Shuo LI ; Yawen WANG ; Guangjian ZHANG
Organ Transplantation 2025;16(1):147-155
After continuous development and improvement, lung transplantation has become the preferred means to treat a variety of benign end-stage lung diseases. However, the field of lung transplantation still faces many challenges, including shortage of donor resources, preservation and maintenance of donor lungs, and postoperative complications. Lung tissue samples removed after lung transplantation are excellent clinical resources for the study of benign end-stage lung disease and perioperative complications of lung transplantation. However, at present, the collection, storage and utilization of tissue samples after lung transplantation are limited to a single study, and unified technical specifications have not been formed. Based on the construction plan of the biobank for lung transplantation in the First Affiliated Hospital of Xi'an Jiaotong University, this study reviewed the practical experience in the collection, storage and utilization of lung transplant tissue samples in the aspects of ethical review, staffing, collection process, storage method, quality control and efficient utilization, in order to provide references for lung transplant related research.
5.Exploration of Pulmonary Vascular Remodeling Improvement in Rats at Different Stages of Chronic Obstructive Pulmonary Disease by Qibai Pingfei Capsules Based on TLR4/NF-κB Signaling Pathway
Lu ZHANG ; Li FANG ; Shuyu XU ; Xue LIANG ; Jie ZHU ; Xiangli TONG ; Zegeng LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(9):48-56
ObjectiveTo investigate the improvement effect of Qibai Pingfei capsules on pulmonary vascular remodeling in rats at different stages of chronic obstructive pulmonary disease (COPD) and to analyze its possible mechanism of action. MethodsMale Sprague-Dawley (SD) rats were randomly divided into a normal group, an early COPD model group, an advanced COPD model group, an early-intervention high-dose group, a late-intervention high-dose group, an early-intervention low-dose group, a late-intervention low-dose group, an early-intervention pyrrolidine dithiocarbamate (PDTC) group, and a late-intervention PDTC group, with 15 rats in each group. A rat model of early COPD was constructed by using cigarette smoke combined with airway infusion using lipopolysaccharide(LPS), and a rat model of advanced COPD was constructed by using airway infusion with LPS, cigarette smoke, and hypoxia. All groups except the normal group were given LPS airway drops on days 1 and 14 of the experiment, smoked for 1 h per day, and administered the drug once a day for 40 weeks from day 15 onward. In the high- and low-dose groups, rats were given 1 g·kg-1 and 250 mg·kg-1 Qibai Pingfei capsules, respectively by gavage, and in PDTC groups, rats were given 100 mg·kg-1 of PDTC by intraperitoneal injection. The advanced COPD model group underwent 6 h of hypoxia per day in weeks 5-6. Lung function and mean pulmonary artery pressure were tested in rats. Morphologic changes in lung tissues were detected by hematoxylin-eosin(HE)staining. Collagen deposition in lung tissues was examined by Masson staining, and the levels of inflammatory factors including interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α)in lung tissues were detected by enzyme-linked immunosorbent assay (ELISA). The number of inflammatory cells in the alveolar lavage fluid of rats in each group was detected by Giemsa staining, and the protein expression of Toll-like receptor 4(TLR4), myeloid differentiation factor 88(MyD88), nuclear factor-κB(NF-κB), TNF-α, vascular endothelial-cadherin(VE-cadherin), α-smooth muscle actin(α-SMA), and platelet endothelial cell adhesion molecule-1(CD31) was detected by Western blot in the lung tissues of rats. ResultsCompared with the normal group, the model group showed significantly decreased forced expiratory volume in 0.3 s (FEV0.3), forced vital capacity (FVC), and FEV0.3/FVC ratio related to lung function (P<0.05), thickening of pulmonary vasculature, increased collagen deposition in the lungs, and enhanced mean pulmonary arterial pressure and expression levels of IL-6, IL-1β, and TNF-α (P<0.05). Additionally, the model group also exhibited increased numbers of macrophages, lymphocytes, and neutrophils (P<0.05), significantly higher protein expression of TLR4, MyD88, NF-κB, TNF-α, and α-SMA (P<0.05), and significantly lower protein expression of VE-cadherin and CD31 (P<0.05). Lung function was significantly improved in the Qibai Pingfei capsules groups compared with the model group (P<0.05), with mean pulmonary arterial pressure reduced and pulmonary vascular thickening and collagen deposition in the lungs ameliorated. The Qibai Pingfei capsules groups also showed reduced expression levels of IL-6, IL-1β, and TNF-α (P<0.05) and decreased numbers of macrophages, lymphocytes, and neutrophils (P<0.05), as well as reduced protein expression of TLR4, MyD88, NF-κB, TNF-α, and α-SMA (P<0.05) and elevated protein expression of VE-cadherin and CD31 (P<0.05) in rat lung tissues. ConclusionQibai Pingfei capsules inhibits inflammatory response and endothelial-to-mesenchymal transition probably by regulating the TLR4/NF-κB signaling pathway, thus improving pulmonary vascular remodeling in COPD model rats and showing therapeutic effects in the early stage of COPD.
6.Research progress of inducing ferroptosis of cancer stem cells against colorectal cancer
Li-Na GONG ; Meng-Ling YUAN ; Xue-Ying CHENG ; Chen-Yang XU ; Jun PAN ; Qiu-Tong CHEN ; Ling WANG ; Zi-Li ZHANG ; Mei GUO
Chinese Pharmacological Bulletin 2024;40(6):1030-1034
Cancer stem cell(CSC)are the"seed"cells in the occurrence,development,metastasis and recurrence of colorectal cancer.Targeted killing of CSC provides a new target for anti-colorectal cancer therapy.Ferroptosis is an iron-dependent cell death mode due to the abnormal accumulation of intracellular i-ron ions,which results in the massive reactive oxygen species(ROS)and lipid peroxides,leading to cell death.Studies have shown that cancer stem cells are more enriched in iron ions than non-CSC,which provides a new perspective for targeting ferropto-sis in cancer stem cells against colorectal cancer.This article re-views the research progress of inducing CSC ferroptosis in the treatment of colorectal cancer,such as targeted regulation of SLC7A11 expression in CSC,chelating iron in CSC lysosomes,targeting CSC phenotypic plasticity,reversing CSC iron homeo-stasis,and targeting CSC lipid droplet metabolism induce CSC ferroptosis,which provides new ideas for anti-tumor therapy.
7.Study on detection of bacterial endotoxin by micro kinetic chromogenic method
Chen-Xue ZHANG ; Tong CAI ; Chen CHEN ; Xiao-Yan ZHAO ; Yu-Sheng PEI
Chinese Pharmacological Bulletin 2024;40(7):1392-1398
Aim To determine whether the micro kinetic chro-mogenic method can meet the requirements of Chinese Pharma-copoeia,as a supplement to the existing bacterial endotoxin test method.Methods Using micro kinetic chromogenic horseshoe crab reagent,the sample volume per well was 25 μL,the detec-tion wavelength was 405 nm,the preset OD value was 0.05,and the detection was carried out by half-well enzyme plate.In accordance with the provisions of"9101 Guiding Principles for Validation of Drug Quality Analysis Methods"in the fourth part of the 2020 edition of the People's Republic of China Pharmaco-poeia,the methodological verification of 7 items of specificity,accuracy,precision,limit of quantification,linearity,range and durability was carried out according to the specific requirements of the"quantitative"item in the"Determination of Impurities".The variety suitability study was conducted on 74 batches of samples from 48 drug varieties,and 143 batches of samples from 76 drug varieties(including 133 batches of negative samples and 10 batches of positive samples)were tested daily,and the re-sults were compared with the results of traditional color rendering method.Results The method of microdynamic color develop-ment met the requirements of the Pharmacopoeia of the People's Republic of China for quantitative methods.The results of varie-tal applicability and consistency comparison showed that the mi-crodynamic color development method had better equivalence compared with the traditional color development method.Con-clusion The micro kinetic chromogenic method can be promo-ted as a supplementary alternative to the existing bacterial endo-toxin methods.
8.Exploring the effects of sirolimus on the growth and development of zebrafish embryo models
Zi-Xin ZHANG ; Tong QIU ; Jiang-Yuan ZHOU ; Xue-Peng ZHANG ; Xue GONG ; Kai-Ying YANG ; Yu-Ru LAN ; Si-Yuan CHEN ; Yi JI
Chinese Pharmacological Bulletin 2024;40(12):2368-2374
Aim To explore the effects of sirolimus on the growth and development of motor,vascular,nerv-ous,and immune systems through zebrafish models.Methods After 3 hours of fertilization of zebrafish embryos,different concentrations of sirolimus were add-ed to the growth environment,and the growth and de-velopment of the embryos was recorded.Transgenic ze-brafish models labeled with blood vessels,nerves or im-mune cells were used to compare the drug effects on the growth and development of those systems.Results At the concentration of 0.5 μmol·L-1,the hatching rate and the body length(P<0.01)were significantly smaller than those of the control group,and movement was also significantly slowed down.Meanwhile,the length of axons of the nervous system,the development of intersegmental vessels,and the growth of immune cells were significantly delayed by drug treatment.But when the concentration was below 0.1 μmol·L-1,there was no statistically difference between the control group and the sirolimus group.Conclusions When the concentration of sirolimus exceeds a certain level,it can significantly slow down the growth and development of movement,blood vessels,nervous system and im-mune system of zebrafish.Therefore,in clinical prac-tice,it is important to monitor the blood concentration of sirolimus in children on time.
9.AI-HIP system for prosthesis size,global femoral offset and osteotomy in total hip arthroplasty
Guo-Yuan SUN ; Yan-Kun JIANG ; Tong LI ; Xue-Feng CONG ; Cheng HUANG ; Ran DING ; Wei-Guo WANG ; Qi-Dong ZHANG
China Journal of Orthopaedics and Traumatology 2024;37(9):848-854
Objective To explore planning effect of AI-HIP assisted surgical planning system in primary unilateral total hip arthroplasty(THA)and its influence on clinical outcomes.Methods A retrospective analysis was conducted on clinical data of 36 patients who underwent their first unilateral THA from March 2022 to November 2022 and continuously used AI-HIP system(AI-HIP group),including 16 males and 20 females,aged from 43 to 81 years old with an average of(62.2±10.9)years old.According to the matching principle,36 patients who were planned by the traditional template method at the same period were selected as the control group,including 16 males and 20 females,aged from 40 to 80 years old with an average of(60.9±12.1)years old.The accuracy between two groups of prostheses were compared,as well as the combined eccentricity difference between preoperative planning and postoperative practice,lower limb length difference,osteotomy height from the upper edge of the lesser trochanter and top shoulder distance to evaluate planning effect.Harris score and visual analogue scale(VAS)were used to evaluate clinical efficacy.Results Both groups were followed up for 12 to 18 months with an average of(14.5±2.1)months.The complete accuracy and approximate accuracy of acetabular cup and femoral stalk prosthesis in AI-HIP group were 72.2%,100%,58.3%,88.9%,respectively,which were better than 44.4%,83.3%,33.3%,66.7%in control group(P<0.05).There was no statistical significance in planning of femoral head prosthesis size(P>0.05).The actual combined eccentricity difference and combined eccentricity difference(practical-planning)in Al-HIP group were 1.0(0.2,2.4)mm and 1.1(-2.1,3.2)mm,respectively;which were better than 3.0(1.4,4.9)mm and 3.5(-1.6,6.5)mm in control group(P<0.05).There was no significant difference between two groups in actual osteotomy height of the upper margin of the lesser trochanter(P>0.05).In AI-HIP group,the actual difference of lower extremity length after surgery,the difference of lower extremity length(practical-planning),osteotomy height from the upper margin of lesser trochanter(practical-planning),actual topshoulder distance after surgery,and topshoulder distance(practical-planning)were 1.5(0.2,2.8),1.1(-0.3,2.2),2.1(-2.3,4.1),(15.3±4.1),2.2(-4.8,0.3)mm,respectively;which were better than control group of 2.6(1.3,4.1),2.5(0.3,3.8),5.8(-2.4,7.7),(13.0±4.3),-5.7(-9.4,-2.2)mm(P<0.05).At final follow-up,there were no significant differences in Harris scores of pain,function,deformity,total scores and VAS between two groups(P>0.05).The range of motion score was 4.8±0.6 in AI-HIP group,which was higher than that in control group(4.4±0.8)(P<0.05).Conclusion Compared with traditional template planning,AI-HIP assisted surgical planning system has good accuracy in predicting the prosthetic size of the acetabular cup and femoral stalk,restor-ing joint eccentricity,planning lower limb length,osteotomy height and top shoulder distance on the first unilateral THA,and the clinical follow-up effect is satisfactory.
10.High tibial osteotomy on varus knee osteoarthritis with medial meniscus posterior root injury
Chun-Jiu WANG ; Xiang-Dong TIAN ; Ye-Tong TAN ; Zhi-Peng XUE ; Wei ZHANG ; Xiao-Min LI ; Ang LIU
China Journal of Orthopaedics and Traumatology 2024;37(9):886-892
Objective To explore clinical effect of distal tibial tubercle-high tibial osteotomy(DTT-HTO)in treating knee osteoarthritis(KO A)with medial meniscus posterior root tear(MMPRT).Methods A retrospective analysis was performed on 21 patients with varus KOA with MMPRT from May 2020 to December 2021,including 3 males and 18 females,aged from 49 to 75 years old with an average of(63.81±6.56)years old,the courses of disease ranged from 0.5 to 18.0 years with an average of(5.9±4.2)years,and 4 patients with grade Ⅱ,14 patients with grade Ⅲ,and 3 patients with grade Ⅳ according to Kellgren-Lawrence;14 patients with type 1 and 7 patients with type 2 according to MMPRT damage classification.The distance of medi-al meniscusextrusion(MME)and weight-bearing line ratio(WBLR)of lower extremity were compared before and 12 months after operation.Visual analogue scale(V AS),Western Ontarioand and McMaster Universities(WOMAC)osteoarthritis index,and Lysholm knee score were used to evaluate knee pain and functional improvement before operation,1,6 and 12 months after operation,respectively.Results Twenty-one patients were followed up for 12 to 18 months with an average of(13.52±1.72)months.MME distance was improved from(4.99±1.05)mm before operation to(1.87±0.76)mm at 12 months after operation(P<0.05).WBLR was increased from(15.49±7.04)%before operation to(62.71±2.27)%at 12 months after operation(P<0.05).VAS was decreased from(7.00±1.14)before operation to(2.04±0.80),(0.90±0.62)and(0.61±0.50)at 1,6 and 12 months after operation.WOMAC were decreased from preoperative(147.90±9.88)to postoperative(103.43±8.52),(74.00±9.54)and(47.62±9.53)at 1,6 and 12 months,and the difference were statistically significant(P<0.05).Lysholm scores were increased from(46.04±7.34)before oepration to(63.19±8.93),(81.10±6.41)and(89.29±3.04)at 1,6 and 12 months after operation(P<0.05).Conclusion For the treatment of varus KOA with MMPRT,DTT-HTO could reduce medial meniscus pro-trusion distance,improve the ratio of lower limb force line,and effectively reduce knee pain and improve knee joint function.

Result Analysis
Print
Save
E-mail