Danshen-Chuanxiong is a traditional herb pair used for cardiovascular and cerebrovascular disorders, but its chemical basis and potential effects in Alzheimer's disease (AD)-related endothelial injury remain incompletely defined. Here, an integrated analytical workflow combining reversed-phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) with quadrupole time-of-flight mass spectrometry (Q-TOF-MS), cellular assays, metabolomics, and network pharmacology was applied in an amyloid-β1-42 (Aβ1-42) oligomer-induced human brain microvascular endothelial cell (hBMEC) injury model. The complementary RPLC/HILIC and positive/negative electrospray-ionization strategy expanded coverage across a broad polarity range. UHPLC-Q/TOF-MS detected 90 compounds, mainly phenolic acids, phthalides, tanshinones, diterpenoids, and other aromatic or terpenoid constituents. The reductions in cell viability and zonula occludens-1 expression following Aβ1-42 exposure confirmed the successful establishment of the cellular injury model, whereas pretreatment with Danshen, Chuanxiong, or their combination increased cell viability and alleviated Aβ1-42-induced cellular injury. Untargeted metabolomics annotated 38 differential metabolites, of which 30 showed a recovery-associated shift toward the control state after Danshen-Chuanxiong treatment; the associated pathways included amino-acid, purine, glutathione, and glycerophospholipid metabolism. Integrative analysis prioritized seven candidate targets of Danshen-Chuanxiong, namely ACHE, VEGFA, NOS2, NOS3, AKR1B1, MDM2, and XDH. These findings provide a separation-MS-based chemical characterization and mechanistic framework for further validation of Danshen-Chuanxiong in AD-related endothelial injury models.
The 5-Hydroxytryptamine (5-HT) level determination is crucial for predicting, pathogenesis, diagnosis, and pharmacological treatment of schizophrenia. To realize the extraction of trace 5-HT in complex matrix samples, a magnetic molecularly imprinted solid-phase extraction (MMISPE) pretreatment method was developed. In combination with UPLC-MS/MS, the method was possible to achieve the quantification of 1 ng/mL 5-HT in tissue samples. The type of adsorbent, magnetic surface molecularly imprinted polymers (MMIPs) adsorbent dosage, adsorption temperature, and adsorption method were screened to obtain the better extraction of 5-HT. After optimizing the extraction and separation method, we applied the MMISPE method to the detection of 5-HT in peripheral blood of clinical schizophrenia patients. The results showed that the average concentration of 5-HT in the peripheral blood of healthy controls was 74.30 ng/mL, whereas the 5-HT content in the samples from schizophrenic patients was 1.17 ng/mL.
Cholangiocarcinoma (CCA) is an aggressive malignancy with a poor prognosis. Nitidine chloride (NitC), a bioactive alkaloid derived from Zanthoxylum nitidum (Roxb.) DC., exhibits potential anti-cancer activity against CCA. However, the metabolic mechanism underlying the anti-cancer effect of NitC remains poorly understood and requires further elucidation. This study integrated metabolomics and network pharmacology to systematically investigate the anti-cancer activity and underlying mechanisms of NitC in treating human cholangiocarcinoma cells. First, The effects of NitC on human cholangiocarcinoma cells were assessed by cell proliferation, apoptosis, and cycle. Then, potential mechanisms and targets were investigated using a combination of cell metabolomics and network pharmacology and verified by molecular docking. Finally, we measured the protein levels of potential targets in TFK1 cells using enzyme-linked immunosorbent assay (ELISA). Our results indicated that NitC treatment induced the proliferation inhibition, G2/M arrest and apoptosis of TFK1 cells in a concentration dependent manner. The metabolomics analysis identified forty differential metabolic biomarkers and five key metabolic pathways of NitC in treating CCA. Network pharmacology found 36 potential targets for NitC intervention on CCA. The integration of network pharmacology and metabolomics constructed the "compound-reaction-enzyme-gene" association and revealed that NitC exerts its efficacy on CCA through four key targets, eleven metabolic indicators, and glycine, serine and threonine metabolism, and tyrosine metabolism. Molecular docking further confirmed robust binding interactions between NitC and these key targets. Moreover, ELISA results showed that NitC treatment significantly attenuated the protein levels of PIK3CA, PTGS2, and PRKACA in TFK1 cells. This study demonstrates that combining metabolomics and network pharmacology provides a powerful strategy to elucidate the pharmacological mechanisms of natural compounds, also offering new insights into the therapeutic potential of NitC for CCA.
ETHNOPHARMACOLOGICAL RELEVANCE:Bu-Wang San (BWS) is a prominent traditional Chinese medicine known for calming the mind and promoting intelligence. It has been reported to improve learning and memory, enhance memory ability, and promote synaptic plasticity. However, the complexity of the material basis and the diversity of therapeutic targets of BWS on Alzheimer's disease (AD) have not been elucidated. AIM OF THE STUDY:This study aimed to investigate the therapeutic material basis and the mechanism of BWS in AD treatment by comprehensively analyzing multiple GEO datasets of the human hippocampus, network pharmacology, and multi-platform metabolomics validation. MATERIALS AND METHODS:Three GEO datasets of the human hippocampus were utilized to identify AD-associated targets using weighted gene co-expression network analysis (WGCNA) and differential analysis. Network pharmacology analyses were performed to investigate BWS's therapeutic material basis and predict the therapeutic targets of BWS on AD. A rat model was induced through the concurrent administration of AlCl3 and D-galactose to validate BWS's therapeutic potential and underlying mechanisms in AD. To validate the results of GEO data mining and network pharmacology, a comprehensive metabolomics approach integrating gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) was conducted on rat serum samples to uncover potential metabolic alterations and their associated pathways. RESULTS:A total of 6367 genes were selected as AD drug targets through WGCNA analysis and enrichment analysis of disease-associated gene expression profiles in the GEO database. Network pharmacology was performed in this study for the identification of potential interactions between the components of BWS and its targets, TP53, STAT3, EGFR, MAOA, NOS3, PPARG, PRKCA, MAPK8, AChE, ARG1, among others, which were among the top 25 highest probable targets of BWS acting on AD. The multi-platform metabolomics indicated that amino sugar and nucleotide sugar metabolism, glycine, serine and threonine metabolism pathways, and other pathways may be associated with the AD model based on AlCl3 and D-galactose. The comparison of differential metabolites between the AD model group and the BWS intervention group revealed that 66 of the 97 differential metabolites exhibited a pullback trend, indicating a potential therapeutic effect of BWS on these metabolites. CONCLUSION:This study builds a systematic strategy combining GEO datasets, network pharmacology, and multi-platform metabolomics and provides valuable insights into the pharmacological mechanism of BWS on AD. The results suggest that BWS may exert its therapeutic effects on AD by modulating the amino sugar and nucleotide sugar metabolism, glycerophospholipid metabolism, glycine, serine and threonine metabolism pathway and acting on the drug targets of ARG1, MAOA, AChE, XDH, GAD2 et al. This strategy provides a deep understanding of the molecular mechanisms of herbal medicine in treating AD at a systematic level.
Proteins are indispensable to all biological systems and drive life processes through activities that are intricately linked to their three-dimensional (3D) structures. Traditional proteomics often provides static snapshots of protein expression, leaving unanswered questions about how proteins respond to stimuli and affect cellular functions. Limited proteolysis coupled with mass spectrometry (LiP-MS) has emerged as a powerful technique for exploring protein structure and function under near-natural conditions. Studies have revealed that LiP-MS is invaluable for structural and functional proteomics because it offers novel insights into protein dynamics. In this review, we summarise the current applications of LiP-MS in diverse areas such as the discovery and identification of drug targets, metabolite action mechanisms, proteome dynamics, protein interactions, and disease biomarkers. We also address the critical challenges in ongoing research and discuss their broader implications for advancing our understanding of protein biology and drug discovery. LiP-MS holds significant promise for accelerating biomarker and therapeutic target development as well as advancing molecular biology research in animals, plants, and microorganisms.
Traditional Chinese Medicine (TCM) is a supremely valuable resource for the development of drug discovery. Few methods are capable of hunting for potential molecule ligands from TCM towards more than one single protein target. In this study, a novel dual-target surface plasmon resonance (SPR) biosensor was developed to perform targeted compound screening of two key proteins involved in the cellular invasion process of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): the spike (S) protein receptor binding domain (RBD) and the angiotensin-converting enzyme 2 (ACE2). The screening and identification of active compounds from six Chinese herbs were conducted taking into consideration the multi-component and multi-target nature of Traditional Chinese Medicine (TCM). Puerarin from Radix Puerariae Lobatae was discovered to exhibit specific binding affinity to both S protein RBD and ACE2. The results highlight the efficiency of the dual-target SPR system in drug screening and provide a novel approach for exploring the targeted mechanisms of active components from Chinese herbs for disease treatment.
Multidrug resistance (MDR) is a dominant challenge in cancer chemotherapy failure. The over -expression of breast cancer resistance protein (BCRP) in tumorous cells, along with its extensive substrate profile, is a leading cause of tumor MDR. Herein, on the basis of styrene maleic acid (SMA) polymer membrane protein stabilization strategy and surface plasmon resonance (SPR) biosensor, a novel high -throughput screening (HTS) system for BCRP inhibitors has been established. Firstly, LLC-PK1 and LLC-PK1/BCRP cell membranes were co -incubated with SMA polymers to construct SMA lipid particles (SMALPs). PK1-SMALPs were thus immobilized in channel 1 of the L1 chip as the reference channel, and BCRP-SMALPs were immobilized in channel 2 as the detection channel to establish the BCRP-SMALPs-SPR screening system. The methodological investigation demonstrated that the screening system was highly specific and stable. Three active compounds were screened out from 26 natural products and their affinity constants with BCRP were determined. The K D of xanthotoxin, bergapten, and naringenin were 5.14 mu M, 4.57 mu M, and 3.72 mu M, respectively. The in vitro cell verification experiments demonstrated that xanthotoxin, bergapten, and naringenin all significantly increased the sensitivity of LLC-PK1/ BCRP cells to mitoxantrone with possessing reversal BCRP-mediated MDR activity. Collectively, the developed BCRP-SMALPs-SPR screening system in this study has the advantages of rapidity, efficiency, and specificity, providing a novel strategy for the in-depth screening of BCRP inhibitors with less side effects and higher efficacy.
Osteoporosis is a global health challenge characterized by bone loss and microstructure deterioration, which urgently requires the development of safer and more effective treatments due to the significant adverse effects and limitations of existing drugs for long-term treatment. Traditional Chinese medicine, like Epimedium, offers fewer side effects and has been used to treat osteoporosis, yet its active compounds and pharmacological mechanisms remain unclear. In this study, 65 potential active compounds, 258 potential target proteins, and 488 pathways of Epimedium were identified through network pharmacology analysis. Further network analysis and review of the literature identified six potential active compounds and HIF-1α for subsequent experimental validation. In vitro experiments confirmed that 2″-O-RhamnosylIcariside II is the most effective compound among the six potential active compounds. It can promote osteoblast differentiation, bind with HIF-1α, and inhibit both HIF-1α gene and protein expression, as well as enhance COL1A1 protein expression under hypoxic conditions. In vivo experiments demonstrated its ability to improve bone microstructures and reduce bone loss by decreasing bone marrow adipose tissue, enhancing bone formation, and suppressing HIF-1α protein expression. This study is the first to describe the therapeutic effects of 2-O-RhamnosylIcariside II on osteoporosis, which was done, specifically, through a mechanism that targets and inhibits HIF-1α. This study provides a scientific basis for the clinical application of Epimedium and offers a new candidate drug for the treatment of osteoporosis. Additionally, it provides new evidence supporting HIF-1α as a therapeutic target for osteoporosis.
Metabolomics intends to maximize the quantity of available metabolites for the global metabolome, which largely depends on sample pretreatment protocols. However, there are few studies that comprehensively examined the effects of extraction and reconstitution solvents on metabolome coverage of adherent mammalian cells. In this study, the human cholangiocarcinoma TFK-1 cells were chosen as a cell model, and eight extraction solvents and five reconstitution solvents were used for the pretreatment based on ultrahigh performance liquid chromatography coupled with mass spectrometry (UPLC/MS). The coverage, reproducibility, and stability of the data were norms to evaluate the effectiveness of different extraction solvents and reconstitution solvents. Based on the number of metabolites, the mean Euclidean distance (EDMEAN) in the principal component analysis (PCA) 3D score plots and the relative standard deviation (RSD) distribution of metabolites, it was demonstrated that MeOH-CHCl3-H2O (8:1:1, v/v/v) was the optimal extraction solvent and MeOH-H2O (1:1, v/v) or H2O was superior to other reconstitution solvents for RP column analysis, and the extraction solvent MeOH-ACN-H2O (2:2:1, v/v/v) and the reconstitution solvents ACN-H2O (4:1, v/v) or MeOH-H2O (1:1, v/v) provide the best performance for HILIC column analysis. The optimized pretreatment methods explored in this study expand the coverage of polar and non-polar metabolites and improve the reproducibility and stability of the metabolic data, which can be applied to UPLC/MS-based global metabolomics study on cholangiocarcinoma cells, potentially providing better extraction solvents and reconstitution solvents for other adherent mammalian cells with similar chemical and physical properties.
目的 构建一种心血管芯片模型,评估四种海洋毒素即大田软海绵酸(OA)、芋螺毒素(CTX)、河豚毒素(TTX)和环亚胺毒素(GYM)对血管糖萼组织的损伤,初步探索雷公藤甲素对毒素致伤的保护作用.方法 将人脐静脉内皮细胞(HUVEC)接种于三通道结构的微流控芯片,并对所构建的心血管芯片模型进行表征.采用CCK-8法和免疫荧光染色法分析低、中、高三个浓度的海洋毒素对细胞活力和糖萼组织损伤情况,以及雷公藤甲素对毒素致伤的保护作用.结果 所构建心血管器官芯片中的细胞生长状态良好,具有结构完整的糖萼组织,与对照组相比,OA中、高浓度以及GYM高浓度均对细胞活力具有一定抑制(P<0.05),CTX和TTX在所测浓度下对细胞没有明显活力抑制,但是四种毒素均引起细胞表面糖萼组织的严重损伤(P<0.01),且随着浓度增加,糖萼损伤率升高.经雷公藤甲素预保护后,四种毒素对HUVEC的毒性显著降低,糖萼组织损伤率下降.结论 四种毒素对HUVEC细胞活力以及表面的糖萼组织具有损伤,且呈一定的剂量关系,而雷公藤甲素对毒素损伤后的HUVEC细胞具有保护作用.
Since most anti-glioma drug candidates hardly permeate through the blood-brain barrier (BBB), preclinical models that can integrate the complexity of the tumor microenvironment and the structure and function of the BBB is urgently needed for the treatment of glioma. Herein, we constructed an in vitro BBB-glioma microfluidic chip model lined by primary human brain microvascular endothelial cells, pericytes, astrocytes and glioma cells, which could recapitulate the high level of barrier function of the in vivo human BBB and glioma microenvironment. The BBB unit in BBB-glioma microfluidic chip (BBB-U251 chip) displayed selective permeability to fluorescein isothiocyanate isomer-dextran (FITC-dextran) with different molecular weights and three model drugs with different permeability behavior across BBB, which indicated that this glioma model included a functional barrier. Six potential anti-glioma components in traditional Chinese medicine (TCM) were delivered into the blood channel and the permeated amount was quantified by high-performance liquid chromatography combined with ultraviolet (HPLC-UV). The permeated drugs then directly acted on 3D cultured glioma cells (U251) to evaluate the drug efficacy. The results of permeability coefficients of drugs showed that the data were closer to the in vivo data of traditional Transwell model. The effect of the drugs on U251 cells in the BBB-U251 chip was significantly lower due to the existence of BBB. Drug responses on glioma demonstrated the necessity to take BBB into account during the development of anti-glioma new drugs. Therefore, this 3D glioma microfluidic models integrating the BBB functionality can be a useful platform for screening the anticancer drug for brain tumors.
Kirsten rat sarcoma viral oncogene homolog (KRAS)–phosphodiesterase-delta (PDEδ) is a promising target for antitumor drug discovery. Herein, highly efficient and environmentally sensitive fluorescent probes of PDEδ (DS-Probes) were rationally designed. As compared with the reported PDEδ probes, DS-Probes showed higher binding affinity and selectivity, which were able to conveniently and efficiently label PDEδ in live cells as well as tumor tissues. Therefore, these fluorescent probes are expected to facilitate PDEδ-based mechanism elucidation, drug discovery and pathologic diagnosis.
Salvia miltiorrhiza Bunge (S. miltiorrhiza) is a traditional Chinese medicine that has been widely used in the treatment of various central nervous system (CNS) diseases. However, the mechanism of active components of S. miltiorrhiza crossing the blood-brain barrier (BBB) stays unclear. The purpose of this study was to clarify the mechanism of four ingredients of S. miltiorrhiza, i.e., cryptotanshinone (CTS), dihydrotanshinone I (DTS I), tanshinone IIA (TS IIA), and protocatechuic acid (PCTA) crossing the BBB using the in vitro model. The bidirectional transport of detectable components was tested using the MDCK-MDR1 monolayers. High performance liquid chromatography coupled to triple-quadrupole mass spectrometry (HPLC-QQQ/MS) was used to detect the content changes of S. miltiorrhiza monomer components transported through the BBB. Papp of CTS, DTS I, and TS IIA in the absorption direction were lower than 1.0 × 10-6 cm/s, suggesting that these components were poorly absorbed, while PCTA was moderately absorbed through the BBB. The efflux ratio (ER) of CTS, DTS I, TS IIA, and PCTA were 1.65, 0.92, 4.27, and 1.48, respectively. After treatment with P-gp inhibitor tariquidar, the efflux ratio (ER) of CTS, DTS I, and TS IIA significantly decreased from 1.65 to 1.27, 0.92 to 0.36, and 4.27 to 0.86 (P < 0.05), respectively, while the efflux ratio of PCTA decreased without significance from 1.48 to 0.80. This indicated that the transport of CTS, DTS I, and TS IIA might be related to P-gp. TS IIA and CTS were verified as the substrates of P-gp among the four components since the ER of TS IIA and CTS is greater than 1.5. For PCTA and DTS I, their transport mechanism may be related to other transport proteins or passive transport. The results were confirmed by molecular docking in our current work. In this study, an in vitro BBB model was established and applied to the trans-BBB study of active components in S. miltiorrhiza for the first time, which may provide a basis for further research on the mechanisms of other TCMs in treating CNS diseases and is of great significance in promoting the rational and effective use of TCMs.
Salvia miltiorrhiza Bunge (SM) has been extensively used in Alzheimer's disease treatment, the permeability through the blood-brain barrier (BBB) determining its efficacy. However, the transport mechanism of SM components across the BBB remains to be clarified. A simple, precise, and sensitive method using LC-MS/MS was developed for simultaneous quantification of tanshinone I (TS I), dihydrotanshinone I (DTS I), tanshinone IIA (TS IIA), cryptotanshinone (CTS), protocatechuic aldehyde (PAL), protocatechuic acid (PCTA), and caffeic acid (CFA) in transport samples. The analytes were separated on a C18 column by gradient elution. Multiple reaction monitoring mode via electrospray ionization source was used to quantify the analytes in positive mode for TS I, DTS I, TS IIA, CTS, and negative mode for PAL, PCTA, and CFA. The linearity ranges were 0.1-8 ng/mL for TS I and DTS I, 0.2-8 ng/mL for TS IIA, 1-80 ng/mL for CTS, 20-800 ng/mL for PAL and CFA, and 10-4000 ng/mL for PCTA. The developed method was accurate and precise for the compounds. The relative matrix effect was less than 15%, and the analytes were stable for analysis. The established method was successfully applied for transport experiments on a BBB cell model to evaluate the apparent permeability of the seven components.
阿尔茨海默病(Alzheimer's disease,AD)是1种复杂的神经退行性疾病,研究表明其代谢改变与早期疾病机制有关.为扩大生物系统中代谢物检测的范围,基于多种分析平台联用的代谢组学策略,开发精确有效、侵入性小的生物标志物是AD代谢组学的研究热点,而空间代谢组学为生物组织代谢和药物代谢提供了全新视角.越来越多的中药单体、单味药材及中药复方被证明对AD具有一定的药效作用,从代谢组学角度探讨药效机制,可以提供潜在的生物标志物和代谢模式,有助于定量评价药物疗效及探索作用机制.本文综述了近5年代谢组学在AD病理机制和中药疗效评价研究中的应用进展.
Comprehensive Summary Botulinum neurotoxins serotype A (BoNT/A) is the deadliest toxins known to humans and the "Category A" agent for bioterrorism. Over the past 20 years, significant efforts have been put forth to develop effective inhibitors of BoNT/A. Unfortunately, few identified inhibitors possess noteworthy efficacy against BoNT/A in vivo . Here, we performed a high‐throughput virtual screening based on the structure‐based docking simulations and found a novel potent scaffold 2‐thionicotinate that inhibits the BoNT/A light chain (LC). We then synthesized and optimized a novel series of 2‐thionicotinate derivatives and comprehensively evaluated their activity against BoNT/A in vitro and in vivo . An optimized compound ZM299 effectively exhibits anti‐BoNT/A activity in primary neurons and displayed remarkably therapeutic efficacy against BoNT/A in vivo , which could raise the survival rate of intoxicated mice to 100% (12/12) after lethal doses of BoNT/A exposures. These findings demonstrate that 2‐thionicotinates is a promising scaffold for producing more effective anti‐BoNT/A analogs, and compound ZM299 is worthy of further preclinical evaluation as a drug candidate for the treatment of botulism.
Astragali Radix (AR) is a clinically used herbal medicine with multiple immunomodulatory activities that can strengthen the activity and cytotoxicity of natural killer (NK) cells. However, owing to the complexity of its composition, the specific active ingredients in AR that act on NK cells are not clear yet. Cell membrane chromatography (CMC) is mainly used to screen the active ingredients in a complex system of herbal medicines. In this study, a new comprehensive two-dimensional (2D) NK-92MI CMC/C18 column/time-of-flight mass spectrometry (TOFMS) system was established to screen for potential NK cell activators. To obtain a higher column efficiency, 3-mercaptopropyltrimethoxysilane-modified silica was synthesized to prepare the NK-92MI CMC column. In total, nine components in AR were screened from this system, which could be washed out from the NK-92MI/CMC column after 10 min, and they showed good affinity for NK-92MI/CMC column. Two representative active compounds of AR, isoastragaloside I and astragaloside IV, promoted the killing effect of NK cells on K562 cells in a dose-dependent manner. It can thus suggest that isoastragaloside I and astragaloside IV are the main immunomodulatory components of AR. This comprehensive 2D NK-92MI CMC analytical system is a practical method for screening immune cell activators from other herbal medicines with immunomodulatory effects.
Abstract Background Transketolase (TKT), a key rate‐limiting enzyme in the non‐oxidative branch of the pentose phosphate pathway (PPP), provides more than 85% of the ribose required for de novo nucleotide biosynthesis and promotes the development of hepatocellular carcinoma (HCC). Pharmacologic inhibition of TKT could impede HCC development and enhance treatment efficacy. However, no safe and effective TKT inhibitor has been approved. Methods An online two‐dimensional TKT protein immobilised biochromatographic system was established for high‐throughput screening of TKT ligands. Oroxylin A was found to specifically bind TKT. Drug affinity responsive target stability, cellular thermal shift assay, surface plasmon resonance, molecular docking, competitive displacement assay, and site mutation were performed to identify the binding of oroxylin A with TKT. Antitumour effects of oroxylin A were evaluated in vitro, in human xenograft mice, diethylnitrosamine (DEN)‐induced HCC mice, and patient‐derived organoids (PDOs). Metabolomic analysis was applied to detect the enzyme activity. Transcriptome profiling was conducted to illustrate the anti‐HCC mechanism of oroxylin A. TKT knocking‐down HCC cell lines and PDOs were established to evaluate the role of TKT in oroxylin A‐induced HCC suppression. Results By targeting TKT, oroxylin A stabilised the protein to proteases and temperature extremes, decreased its activity and expression, resulted in accumulation of non‐oxidative PPP substrates, and activated p53 signalling. In addition, oroxylin A suppressed cell proliferation, induced apoptosis and cell‐cycle arrest, and inhibited the growth of human xenograft tumours and DEN‐induced HCC in mice. Crucially, TKT depletion exerted identical effects to oroxylin A, and the promising inhibitor also exhibited excellent therapeutic efficacy against clinically relevant HCC PDOs. Conclusions These results uncover a unique role for oroxylin A in TKT inhibition, which directly targets TKT and suppresses the non‐oxidative PPP. Our findings will facilitate the development of small‐molecule inhibitors of TKT and novel therapeutics for HCC.
Cell membrane affinity chromatography has been widely applied in membrane protein (MP)-targeted drug screening and interaction analysis. However, in current methods, the MP sources are derived from cell lines or recombinant protein expression, which are time-consuming for cell culture or purification, and also difficult to ensure the purity and consistent orientation of MPs in the chromatographic stationary phase. In this study, a novel in situ synthesis membrane protein affinity chromatography (iSMAC) method was developed utilizing cell-free protein expression (CFE) and covalent immobilized affinity chromatography, which achieved efficient in situ synthesis and unidirectional insertion of MPs into liposomes in the stationary phase. The advantages of iSMAC are: 1) There is no need to culture cells or prepare recombinant proteins; 2) Specific and purified MPs with stable and controllable content can be obtained within 2 h; 3) MPs maintain the transmembrane structure and a consistent orientation in the chromatographic stationary phase; 4) The flexible and personalized construction of cDNAs makes it possible to analyze drug binding sites. iSMAC was successfully applied to screen PDGFRβ inhibitors from Salvia miltiorrhiza and Schisandra chinensis. Micro columns prepared by in-situ synthesis maintain satisfactory analysis activity within 72 h. Two new PDGFRβ inhibitors, salvianolic acid B and gomisin D, were screened out with KD values of 13.44 and 7.39 μmol/L, respectively. In vitro experiments confirmed that the two compounds decreased α-SMA and collagen Ӏ mRNA levels raised by TGF-β in HSC-T6 cells through regulating the phosphorylation of p38, AKT and ERK. In vivo, Sal B could also attenuate CCl4-induced liver fibrosis by downregulating PDGFRβ downstream related protein levels. The iSMAC method can be applied to other general MPs, and provides a practical approach for the rapid preparation of MP-immobilized or other biological solid-phase materials.
构建血脑屏障微流控芯片模型,应用于中药活性成分跨血脑屏障渗透性研究.该芯片模型由垂直交叉的两层通道及单层聚碳酸酯膜组成,采用原代人脑微血管内皮细胞,并能模拟血管剪切应力.通过活/死细胞染色和免疫荧光染色观察芯片上细胞生长状态,细胞生长状态良好,且在动态培养下细胞间黏附连接蛋白结构完整;考察该芯片模型对荧光示踪剂和3种模型药物的渗透性和P-糖蛋白(P-gp)的表达情况,结果显示荧光示踪剂和模型药物的渗透性与文献报道一致,芯片上P-gp表达和功能正常,表明该血脑屏障芯片模型具有完整的结构和功能.将构建成功的芯片模型应用于6种中药活性成分跨血脑屏障渗透性评价,采用HPLC-MS/MS法测定跨膜转运液中的药物浓度,获得各成分的Papp结果.延胡索甲素Papp为(4.51±1.90)×10-7cm·s-1、延胡索乙素Papp为(9.10±6.59)×10-7cm·s-1、欧前胡素Papp为(9.38±2.53)×10-7 cm·s-1,而异欧前胡素、黄芩苷和绿原酸浓度低于定量限,推测其在芯片模型上渗透性较低.本研究成功构建血脑屏障微流控芯片模型,屏障功能更加完善且更接近生理环境,有望作为一种新的体外药物渗透性评价工具.