Rhodojaponin VI indirectly targets Cav2.2 channels via N-ethylmaleimide-sensitive fusion protein to alleviate neuropathic pain

Neuropathic pain is a chronic disease that severely afflicts the life and emotional status of patients, but currently available treatments are often ineffective. Novel therapeutic targets for the alleviation of neuropathic pain are urgently needed. Rhodojaponin VI, a grayanotoxin from Rhododendron molle, showed remarkable antinociceptive efficacy in models of neuropathic pain, but its biotargets and mechanisms are unknown. Given the reversible action of rhodojaponin VI and the narrow range over which its structure can be modified, we perforwmed thermal proteome profiling of the rat dorsal root ganglion to determine the protein target of rhodojaponin VI. N-Ethylmaleimide-sensitive fusion (NSF) was confirmed as the key target of rhodojaponin VI through biological and biophysical experiments. Functional validation showed for the first time that NSF facilitated trafficking of the Cav2.2 channel to induce an increase in Ca2+ current intensity, whereas rhodojaponin VI reversed the effects of NSF. In conclusion, rhodojaponin VI represents a unique class of analgesic natural products targeting Cav2.2 channels via NSF.

The stereoselective synthesis of privileged epimer of C-10 carba artemisinins and the effect of substituted groups with different acid-base properties on the antimalarial activity / 药学学报

Artemisinin is a sesquiterpene lactone natural product that contains an endoperoxide bond. Artemisinin has various biological activities including antimalarial, anti-tumor, antiviral and anti-fibrotic activity. Owing to the poor pharmacokinetic properties of artemisinin, its derivatives are currently used in clinic and frequently reported in literature. Although numerous derivatives of artemisinin have been reported, no study has been carried out yet to study the effect of substituted groups with different acid-base property on the antimalarial activity. Among these derivatives, the C-10 carbon artemisinin derivatives are often reported, and their corresponding 10β epimer show much better antimalarial activity than 10α epimer with large-sized substitute. However, there is currently no stereoselective synthesis to efficiently prepare the privileged 10β epimer of C-10 carba artemisinin. To address these two scientific questions, we herein first report an optimized method to stereoselectively synthesize the 10β epimer of C-10 carba artemisinin (98∶2 d.r.). Second, we employed the optimized method to synthesize a series of C-10 carba artemisinin derivatives with different acid-base properties. The antimalarial examination indicated that those derivatives with neutral groups or basic group of short chain showed similar antimalarial activity as dihydroartemisinin (DHA). The acidic group could dramatically decrease the antimalarial effect and was more than 22-fold less effective than DHA or the neutral ones. This study will shed light on the development of new generation of artemisinin derivatives with potent activity.

Research progress of small molecule fluorescent probes for ferrous ion and heme / 药学学报

Small molecule fluorescent probes have gained widespread attention for their advantages of high selectivity, sensitivity, and easy to operate, and have played a critical role in the detection of various species. They have also demonstrated great potential in the field of biomedical research. Iron, as the most abundant transition metal in the human body, plays a vital role in many physiological functions. Due to the influence of the reductive microenvironment of cell, ferrous ion (Fe2+) is the main component of labile iron in living cells. Heme, consisting of Fe2+ and protoporphyrin IX, is one of the main signaling molecules that wrap biological iron in the human body, and also participates in many physiological and pathological processes. Therefore, the development of small molecule fluorescent probes for detecting Fe2+ and heme as effective monitoring tools will help to further understand their pathological and physiological functions, with potential applications in other fields. This review summarizes the research progress of small molecule fluorescent probes for Fe2+ and heme detection in recent years, and provides insights into future directions for their development.

A targeted covalent inhibitor of p97 with proteome-wide selectivity

A resurging interest in targeted covalent inhibitors (TCIs) focus on compounds capable of irreversibly reacting with nucleophilic amino acids in a druggable target. p97 is an emerging protein target for cancer therapy, viral infections and neurodegenerative diseases. Extensive efforts were devoted to the development of p97 inhibitors. The most promising inhibitor of p97 was in phase 1 clinical trials, but failed due to the off-target-induced toxicity, suggesting the selective inhibitors of p97 are highly needed. We report herein a new type of TCIs (i.e., FL-18) that showed proteome-wide selectivity towards p97. Equipped with a Michael acceptor and a basic imidazole, FL-18 showed potent inhibition towards U87MG tumor cells, and in proteome-wide profiling, selectively modified endogenous p97 as confirmed by in situ fluorescence scanning, label-free quantitative proteomics and functional validations. FL-18 selectively modified cysteine residues located within the D2 ATP site of p97. This covalent labeling of cysteine residue in p97 was verified by LC‒MS/MS-based site-mapping and site-directed mutagenesis. Further structure-activity relationship (SAR) studies with FL-18 analogs were established. Collectively, FL-18 is the first known small-molecule TCI capable of covalent engagement of p97 with proteome-wide selectivity, thus providing a promising scaffold for cancer therapy.

The effect of regions-of-interest and elasticity modulus selection on differentiating benign and malignant cervical lymph nodes with shear wave elastography

OBJECTIVE: Imaging diagnosis of cervical lymphadenopathy has conventionally used ultrasonography. Shear wave elastography (SWE) is a recent ultrasound technological advancement that has shown promise in the important medical problem of differentiating between benign and malignant cervical lymph nodes based on quantitative measurements of elasticity modulus. However, widely varying elasticity modulus metrics and regions-of-interest (ROIs) were used in existing studies, leading to inconsistent findings and results that are hard to compare with each other. METHODS: Using a large dataset of 264 cervical lymph nodes from 200 patients, we designed a study comparing three elasticity modulus metrics (Emax, Emean, and standard deviation-SD) with three different ROIs to evaluate the effect of such selections. The metric values were compared between the benign and malignant node groups. The different ROI and metric selections were also compared through receiver operating characteristics curve analysis. RESULTS: For all ROIs, all metric values were significantly different between the two groups, indicting their diagnostic potential. This was confirmed by the ≥0.80 area under the curve (AUC) values achieved with these metrics. Different ROIs had no effect on Emax, whereas all ROIs achieved high performance at 0.88 AUC. For Emean, the smallest ROI focusing on the area of the highest elasticity achieved the best diagnostic performance. In contrast, the larger ROIs achieved higher performances for SD. CONCLUSIONS: This study illustrated the effect of elasticity modulus and ROI selection on the diagnostic performance of SWE on cervical lymphadenopathy. These new findings help guide relevant future studies and clinical applications of this important quantitative imaging modality.

Study on HPLC characteristic fingerprint of substance benchmark of classical famous prescription of Jichuan Decoction / 中草药

Objective: To establish an HPLC characteristic fingerprint of substance benchmark (standard decoction) of classical famous prescription of Jichuan Decoction (JD), and provide reference for the quality study of substance benchmark of JD. Methods: JD standard decoction was prepared according to the ancient method, 15 batches JD standard decoction were determined by HPLC. The similarity analysis and characteristic peak analysis of 15 batches JD were carried out by the "Similarity Evaluation System for Chromatographic Fingerprint of Chinese Materia Medica 2012 version". Results: A total of 18 common characteristic peaks were screened by automatic matching method, peaks 1 and 3 were from Angelicae Sinensis Radix and Cimicifugae Rhizoma, peaks 2, 5, 6, 7, 9, 11 and 13 were from Cistanches Herba, peaks 4, 12, 14, 15 and 17 from were Cimicifugae Rhizoma, peaks 8, 10 and 18 from Aurantii Fructus, and peak 16 was from Angelicae Sinensis Radix. Seven characteristic components were identified by the reference substance, including caffeic acid (peak 1), echinacoside (peak 2), ferulic acid (peak 3), isoferulic acid (peak 4), mullein glycoside (peak 6), naringin (peak 8) and neohesperidin (peak 10). The similarities of 15 batches substance benchmark of JD were greater than 0.9. Conclusion: The HPLC method established for substance benchmark of JD is simple, accurate, stable and sensitive. It can be used for the quality study for JD substance benchmark, and provides a reference for the transformation and development of JD for modern preparations.

Protein targets of medicinally active molecules based on their original structures and molecular probes / 药学学报

Medicinally active molecules are those that have pharmacological effects. Research on protein targets of these molecules not only clarifies their mechanism of action, but also deepens our understanding of biological systems. Here we review recent advances in protein targets of drugs used in clinical practice or in preclinical research. They have various functions including anti-inflammatory, anti-malarial, anti-tumor and other biological activities. Activity-based protein profiling (ABPP) and cellular thermal shift assay (CETSA) are two useful methods to identify the protein targets of small molecules. ABPP depends on a derivative active molecule probe to pull down the protein targets to reveal the interaction mechanisms between the active molecules and targets. Drug target engagement also can be assessed by means of CETSA based on ligand-induced changes in protein thermal stability. In the CETSA approach, the active molecules do not need to be chemically modified. Combining the CETSA method with quantitative mass spectrometry is an effective approach to study the effect of compounds on the thermal profile of a cellular proteome and identify the protein targets. ABPP and CETSA can be complementary and effectively clarify the protein targets. The study of protein targets will help reveal the mechanism of action of medicinal molecules, reveal toxic mechanisms and aid in the discovery of new medicinal targets to promote the process of drug development.

Fast Identification of Cyathula officinalis and Its Adulterant and Doped Adulterant Based on Properties and Foam Test / 中国实验方剂学杂志

Objective: To rapidly identify Cyathula officinalis and its adulterant C. capitata and C. officinalis*C. capitata and doped adulterant. Method: Properties combined with foam test method were used for identifying C.officinalis, its adulterant and doped adulterant. In the aspect of properties,6 aspects including shape,size,texture,color,smell and taste,were observed, smelled and tasted. In the aspect of foam test,the volume of foam produced was used as the determination index to investigate the sample amount,water amount, shaking time,particle size,water temperature,repeatability,adulteration ratio and its stability. Result: In the aspect of properties,C. officinalis and its adulterant showed obvious difference in the shape,size,color,texture,smell and taste,especially the red color and bitter taste of its adulterant. In the aspect of foam test,the optimum parameters were as follows:sample particle (screened with 3 sieves) 0.3 g,a test tube with plug and scale,water 10 mL and airtight,forced shaking up and down for 1 min,settling for 5 min. Such method can be used to identify C. officinalis, its adulterant and doped adulterant. The volume of foams produced by C. officinalis and its adulterant and different ratio of doped adulterant showed no change within 5-30 min,slightly decreases after 9 h; the higher adulteration ratio; the larger volume of foam and better stability. The 8 batches of C. officinalis and 8 batch of adulterants proved that the volume of the foams produced was all less than 2 mL in the C. officinalis,more than 13 mL in the adulterant is,and more than 5 mL in 5% doped adulterant, showing statistical difference. From the properties combined with foam test,5 specific identification elements were obtained for identifying C. officinalis, its adulterant and doped adulterant. Conclusion: Through the 5 specific identification elements,the properties combined with foam test can be used to distinguish the C. officinalis from its adulterant C. officinalis and C. officinalis*C. capitata and doped adulterant,characterized by accuracy,simpleness,short time,low cost and feasibility. It can provide a new method and reference for identifying C.officinalis from its adulterant and doped adulterant.

Comparation of chemical composition of Cyathula offinalis between different growth years by HPLC characteristic fingerprint combined with chemometrics / 中草药

Objective HPLC characteristic fingerprint and chemometrics method were used to compare the chemical characteristics difference between 1-6 years old Cyathula offinalis. Methods The peak area data matrix of 6 × 54 and the difference of characteristic peak of 1-6 years old C. offinalis were analyzed by HPLC. Similarity analysis the samples was investigated with “Similarity Evaluation System for Chromatographic Fingerprint of Chinese Materia Medica 2004A”. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) were carried out with SPSS 22.0 software. Results According to the analysis of characteristic peak difference, 1 and 6 years old C. offinalis showed exclusive difference in four chromatographic peaks and five chromatographic peaks, respectively. The peak area of 1 year old sample was significantly higher than other years in four chromatographic peaks, which showed obvious differences in components cumulant. The similarity degree analysis showed that the similarity degree of the 3, 4, and 5 years old C. offinalis were more than 0.98, but the 1, 2 and 6 years old were less than 0.85. Dendrogram of HCA and 3D scatter plot of PCA showed that the 3, 4, and 5 years old C. offinalis were clustered into one class. Conclusion There are certain differences in the chemical components among different growth years of C. offinalis. The chemical components of the 3, 4, and 5 years old C. offinalis tend to be uniform, which provides a scientific reference for the harvest time of C. offinalis.

Comparison of chemical constituents between Cyathula offinalis and adulterant and their admixture by HPLC characteristic chromatogram fingerprint combined with chemometrics / 中国中药杂志

Cyathula capitate is the main adulterant of C.offinalis. According to the literature reported, there are obvious differences in properties, taste and pharmacological activity between C. capitate and C.offinalis. Therefore, C. capitate can only be used as a local conventional medicine and can't be a substitute for C. offinalis. Since the appearance of C.capitata is very similar to the C.offinalis and the content of cyasterone also can reach the limit of the current pharmacopoeia standard, the C.capitata is mostly sold in the form of impersonation oradmixture, which seriously affected the safety of the clinical medication and the development of the genuine crude drugs. In view of this, HPLC characteristic fingerprint was used to reveal the difference of multi-ingredients of C. offinalis, C. capitata and their admixture. According to the HPLC chromatogram of C.offinalis, C. capitata. and their admixture, 65 different components were obtained to set up a peak area data matrix of 26×65, which was applied to perform the characteristic peak difference analysis, similarity analysis, hierarchical clustering analysis HCA and principal component analysis (PCA). Characteristic peak difference analysis showed that the characteristic peaks of C. capitata and their admixture are more and higher respond than those of C. offinalis. The 9 characteristic peaks were used to distinguish C. capitata, 2 of which were used to distinguish C. offinalis mixed with 5% C. capitata. UV spectra of 9 characteristic peaks are mostly similar to the end absorption spectra of saponins, indicating that C. capitata may contain a large amount of saponins. By the reference fingerprint of C.offinalis established, the similarity analysis showed that the similarity degree of C. offinalis are higher than 0.942, while the similarity degree of C. capitata, C.offinalis mixed with 5% C. capitata are less than 0.383 and 0.399. C.offinalis, C. capitata, C.offinalis mixed with 5% C. capitata could be obviously divided into 3 classes by HCA and PCA. These results showed that there are obvious difference in the chemical composition of C. offinalis, C. capitata and their admixture, which could provide evidence for their identification.

Recent advances in the study of pin1 and its inhibitors / 药学学报

Pin1 is a phosphorylation-dependent peptidyl-prolyl cis/trans isomerase, which specifically catalyzes the amide bond isomerization of phosphoserine-proline or phosphothreonine-proline in mitotic phosphoproteins. Pin1 induces the conformational changes to control the function of phosphoproteins. Depletion of Pinl on various human cancer cell lines cause mitotic arrest and apoptosis. Pin1 is an attracting therapeutic target for anticancer and its inhibitors might be potential anticancer drug. In this review, Pin1 inhibitors and the catalytic mechanism, the biological function of Pin1 and its role in oncogenesis are summarized.

A Discussion of Interventional Therapy in Advanced Esophageal Carcinoma / 介入放射学杂志

Bronchoarterial and left gastric arterial drug infusion therapy were carried out in 27 cases of inoperable,advanced esophageal cancer;with DMVC method on squa- mous carcinoma and FAM method on adenocarcinoma.Near future good results were ob- tained by raising the survival rate and life quality.The authors put emphysis on the discus- sion of the indications and theoratic points of interventional therapy.