Screening of anti-SARS-CoV-2 ligands from Chinese herbs based on a dual-target surface plasmon resonance biosensor / 药学学报

The epidemic of COVID-19 has brought great challenges to the global public health prevention and control system combined with clinical diagnosis and treatment system, and it makes the development of effective antiviral drugs an important task in current pharmaceutical research. Traditional Chinese medicine (TCM) has played an important role in the prevention and control of COVID-19. Due to its numerous chemical components and various structural types, TCM becomes a natural library for searching for lead compounds against SARS-CoV-2. In this study, a novel dual-target surface plasmon resonance (SPR) biosensor was developed for S protein receptor binding domain (SRBD) and angiotensin converting enzyme 2 (ACE2) which are two key proteins in the process of SARS-CoV-2 invading cells according to characteristics of synergistic effects of multiple components and comprehensive regulation of multiple targets of TCM. The SPR biosensor was applied to screen and identify active components from six TCMs, and daidzin from Puerariae Lobatae Radix was identified to bind with SRBD and ACE2. The affinity constant (KD) of daidzin and ACE2 was 5.18 μmol·L-1 through the SPR affinity assay. Competitive ELISA assay showed that daidzin could inhibit the binding of SRBD and ACE2, and the inhibition rate of daidzin (20 μmol·L-1) was 38.6%. Molecular docking experiments further confirmed that daidzin had the best binding near the binding region of SRBD-ACE2 complex. This study shows that the dual-target SPR screening system is accurate and efficient, and is particularly suitable for screening of complex drug systems and effective substances study of TCM. It provides a material basis for exploring the mechanism of TCM active constituents against SARS-CoV-2, and provides a source of lead compounds for the development of anti-SARS-CoV-2 drugs.

The fenrou zhijian theory in The Inner Canon of Huangdi and the stratified treatment of painful bi syndrome of meridian tendons / 中国针灸

The fenrou zhijian is defined as potential gap between different layers in the three-dimensional network structure formed by the twelve meridian tendons. Various pathological changes of the meridian tendons lead to the adhesion and closure of fenrou zhijian, causing abnormal mechanical conduction of the meridian tendon system, which in turn leads to painful bi syndrome of meridian tendons. As such, restarting the fenrou zhijian is the key to acupuncture treatment for painful bi syndrome of meridian tendons. Under the guidance of musculoskeletal ultrasound, the level and the angle of needle insertion of acupuncture at fenrou zhijian could be accurately controlled, the efficacy of acupuncture is improved.

Effect of Buyi Pishen acupuncture on inflammatory factor and cartilage matrix in adjuvant arthritis rats / 中国针灸

OBJECTIVE@#To observe the effect of Buyi Pishen acupuncture (acupuncture for invigorating spleen and kidney) on inflammatory factor and synovial cartilage matrix in adjuvant arthritis (AA) rats, and to explore the mechanism of acupuncture for rheumatoid arthritis (RA).@*METHODS@#A total of 60 clean male Wistar rats were randomized into a normal group, a model group, a tripterygium wilfordii polyglycoside tablet (TWP) group and an acupuncture group, 15 rats in each group. Rats in the model group, the TWP group and the acupuncture group received intradermal injection of Freund's complete adjuvant (FCA) at right hind foot pad to induce the AA model. TWP suspension of 8 mg/kg was given by gavage in the TWP group. Acupuncture was applied at "Shenshu" (BL 23), "Pishu" (BL 20) and right "Housanli" (ST 36), "Sanyinjiao" (SP 6), "Yanglingquan" (GB 34) in the acupuncture group, 15 min a time, once a day. The intervention was given 15 days in both TWP group and acupuncture group. The foot-pad swelling degree before modeling, before and after intervention and the arthritis index (AI) score before and after intervention were calculated; the serum levels of interleukin (IL)-1β, IL-4, IL-10 and tumor necrosis factor-α (TNF-α) were detected by ELISA method; the ultrastructure and histomorphological changes of synovium issue were observed by transmission electron microscope and HE staining; the positive expression of matrix metalloproteinase (MMP)-3 and MMP-9 in synovium issue was detected by immunohistochemistry method.@*RESULTS@#Before intervention, foot-pad swelling degree of the model group, the TWP group and the acupuncture group was increased compared with the normal group (P<0.01). After intervention, foot-pad swelling degree and AI score were increased compared with the normal group (P<0.01), foot-pad swelling degree and AI scores in the TWP group and the acupuncture group were lower than the model group (P<0.05), and those in the acupuncture group were decreased compared with the TWP group (P<0.05). The model group exhibited unclear nuclear membrane of synovial cells, chromatin pyknosis, massive inflammatory cell infiltration and hyperplasia in synovial tissue; the TWP group and the acupuncture group exhibited clear and smooth nuclear membrane of synovial cells, inapparent chromatin pyknosis, less inflammatory cell infiltration and hyperplasia in synovial tissue, the acupuncture group exhibited less matrix destruction as well. Compared with the normal group, serum levels of IL-1β and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were increased (P<0.01), while serum levels of IL-4 and IL-10 were decreased (P<0.01) in the model group. Compared with the model group, serum levels of IL-1β and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05, P<0.01), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the TWP group and the acupuncture group; compared with the TWP group, serum level of TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the acupuncture group.@*CONCLUSION@#Buyi Pishen acupuncture can effectively improve the injury of articular cartilage in AA rats, its mechanism maybe related to reducing the inflammatory reaction in synovium and inhibiting the degradation of articular cartilage matrix.

Screening of immune cell activators from Astragali Radix using a comprehensive two-dimensional NK-92MI cell membrane chromatography/C18 column/time-of-flight mass spectrometry system / 药物分析学报

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 acti-vators.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 compo-nents 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.

N-butanol extract of Hedyotis diffusa protects transgenic Caenorhabditis elegans from Aß-induced toxicity.

Hedyotis diffusa Willd (Rubiaceae) is a widely used and resourceful traditional Chinese medicine that exerts protection against aging and age-related diseases. However, the underlying mechanisms of the protective effects remain largely unclear. Alzheimer's disease (AD) is an age-related neurodegenerative disease, of which ß-amyloid (Aß)-induced toxicity has been suggested as a main cause. Herein, we use the transgenic Caenorhabditis elegans CL4176, CL2006, and CL2355 strains, which express human Aß1-42 peptide, to investigate the effects and the possible mechanisms of n-butanol extract of H.diffusa (HDB)-mediated protection against Aß toxicity in vivo. During the experiments, a method of quality control for HDB was established by HPLC. Additionally, we examined the effects of HBD on gene expression changes with qRT-PCR, aggregation of Aß plagues with thioflavin-S staining, and protein detection with GFP labeling. HDB improved lifespan, locomotion, and stress resistance. Further study showed that HDB decreased paralysis, the accumulation of ROS, and AChE activity. Moreover, HDB suppressed neuronal Aß-expression-induced defects in chemotaxis behavior and increased SOD activity. HDB also downregulated the Aß mRNA level and decreased the number of Aß deposits. Furthermore, HDB increased the expression levels of sod-3, daf-16, hsf-1, and hsp-16.2 gene and upregulated hsp-16.2::GFP and gst-4::GFP expression. Taken together, these results suggest that HDB may protect against Aß-induced toxicity in C. elegans via the insulin/insulin-like growth factor-1 (IGF-1) signaling pathway.

Isomeric discrimination of kaempferol versus luteolin by online energy-resolved mass spectrometry / 中国中药杂志

Isomers are widely distributed in Chinese herbal medicines,and can be discriminated by energy-resolved mass spectrometry( ER-MS). However,ER-MS was performed through direct injection of reference compounds with syringe pump,which encountered a significant technical barrier for high-throughput and automated measurements. Herein,online ER-MS was conducted using LC-MS platform,and a pair of isomers,kaempferol vs luteolin,were employed as a case study to illustrate and assess the utility of online ER-MS for isomeric discrimination. High-resolution tandem mass spectrometry data of both flavonoids were acquired on LC-QE-Orbitrap-MS,and the fragmentation pathways responsible for the primary fragment ions were proposed. The primary signal in MS1 occurred at m/z 285( [M-H]-),and the primary signals of either compound generated by retro-Diels-Alder fragmentation were observed at m/z 151 and 133. The spectral information was subsequently transferred onto LC-Qtrap-MS platform to carry out online ER-MS. Two precursor-to-product ion transition candidates were constructed as m/z 285>151 and 285>133,and either afterward derived a set of pseudo-ion transitions( PITs) and so forth,exactly corresponding to a series of progressive collision energies( eg-5,-8,-11 e V,and so on). All PITs were typed into the monitoring list of multiple reaction monitoring program to generate the peak area datasets. Either dataset was normalized using the highest values in the set and imported into Graph Pad Prism software to plot the Gaus-sian-shaped curve that was termed as the break-down graph. The apex of the regressive curve was termed as optimal collision energy( OCE). The OCE values corresponding to m/z 285>151 were calculated as-29. 06 e V and-35. 71 e V for kaempferol and luteolin,respectively. In the case of m/z 285>133,the OCEs were yielded as-44. 15 e V for kaempferol and-49. 01 e V for luteolin. With re-ference to their chemical structures,the location of hydroxyl group was regarded to be responsible for the differences of either m/z 285>151 or 285>133 between the isomers,attributing to their different bond properties. Above all,online ER-MS offers an eligible tool for isomeric discrimination,and provides meaningful information for the accurate chemical composition characterization based on LC-MS,which is not limited to Chinese herbal medicines.

Interpretation of therapeutic effect of / 中国针灸

Given that the biomechanical theory cannot well explain the therapeutic effect of

Bile acid derivatives-focused chemical profiling in snake bile / 中国中药杂志

As a precious traditional Chinese medicine(TCM), snake bile has been widely used in numerous Chinese medicine prescriptions. Bile acid(BA) derivatives have been demonstrated as the primary chemical family in snake bile. In-depth chemical characterization of BAs is of great importance towards the establishment of quality standards and clarification of the effective material basis for snake bile. This study firstly employed ~1H-NMR to preliminarily analyze the chemical profiles of snake bile, an automated fraction collector was subsequently implemented to obtain the fractions-of-interest. The fraction was then concentrated and re-analyzed by LC-MS. Based on ~1H-NMR, BAs were found to be the main components of snake bile, and six BAs including CDCA, CA, TCDCA, TCA, TDCA and GCA were tentatively identified from the representative spectrum with the assistance of literature and reference compounds. Whereas the content of TCA in snake bile was too great, resulting in a great obstacle for the detection of trace components, the automated fraction collector was subsequently implemented to obtain the fractions-of-interest for LC-MS analysis. According to matching MS/MS information and retention time with reference compounds as well as database retrieval, a total of 57 BAs were detected and annotated. Because of the combination of ~1H-NMR and LC-MS platforms, the findings are beneficial for the in-depth characterization of BAs in snake bile, which provides references for the establishment of quality control and evaluation methods of snake bile.

[Chemical profiling of Artemisia rupestris using HPLC-IT-TOF-MS].

Artemisia rupestris is widely used as a folk medicine of Uygur and Kazak with blood and detoxification, deaccumulation stagnation, clearing heat digestion and other effects. Currently, the chemical profile of A. rupestris has not been disclosed, resulting in a great obstacle for the systematic clarification of the efficacy materials and the quality evaluations. In this paper, HPLC-IT-TOF-MS was deployed to characterize the chemical constituents in A. rupestris. As a result, a total of 124 compounds were detected in 75% ethanol extract of A. rupestris. By comparing with the reference compounds, seven chlorogenic acids, and four flavonoids as well as one sesquiterpenoid were definitely identified. Moreover, twenty sesquiterpenes, sixty-five flavonoids and twenty-three chlorogenic acids were preliminarily identified by matching MS/MS spectral information with literature data and applying those empirical mass spectrometric cracking rules. In current study, the chemical composition of A. rupestris was profiled in depth, and the findings are envisioned to provide a theoretical basis for the further studies of this well-known herbal medicine, such as efficacy material characterization and quality assessment.

Evaluation of taste changes of Scutellariae Radix before and after wine-frying based on electronic ongue technology and its application in identification of Scutellariae Radix pieces / 中国中药杂志

Scutellariae Radix(Huangqin) is a well-known traditional Chinese medicine(TCM) used for the treatment of clearing heat in clinical application. It is bitter-cold by using directly, but the bitter-cold property can be relieved after wine-frying. The study of taste changes before and after wine-frying of Scutellariae Radix is of great significance in identifying Scutellariae Radix and wine-processed Scutellariae Radix and clarifying the traditional theory of wine-processing. In this experiment, 10 batches of Scutellariae Radix and wine-processed Scutellariae Radix were prepared. The contents of 5 flavonoids were determined by high performance liquid chromatography(HPLC), and principal component analysis(PCA) was performed with 5 flavonoids as variables. As a result, the contents were different in different batches of Scutellariae Radix, but Scutellariae Radix and wine-processed Scutellariae Radix could not be distinguished. Five sensory attributes(sour, salty, fresh, sweet, and bitter) were evaluated by artificial tasting, and the response values of 7 sensors(AHS, AHS, PKS, CTS, NMS, CPS, ANS, SCS) representing the taste of pieces were detected by electronic tongue. The correlation between sensory evaluation and response values of the electronic tongue were analyzed, and the results showed that the sensory evaluation of sour, salty, fresh, sweet, bitter and AHS, CTS, NMS, ANS, SCS sensors had different degrees of correlation, indicating that the electronic tongue technology can be used as an alternative to artificial taste and can serve as a means for quantifying the taste, and it can be used to evaluate the taste of TCM pieces. The taste method was used to analyze the response values of the electronic tongue, and the results showed that the bitterness of wine-processed Scutellariae Radix decreased and the salty taste increased. PCA was used to analyze taste changes before and after wine-processed Scutellariae Radix, and the results showed that taste differences between 2 pieces were divided into 2 categories. PCA loading scattering plots showed that response of saltiness and bitterness were the major factors to affect overall taste in Scutellariae Radix and wine-processed Scutellariae Radix. Based on electronic tongue response values, the Fisher discriminant model for Scutellariae Radix and wine-processed Scutellariae Radix was established, which showed that it could effectively discriminate them with a recognition rate of 100%. The experimental results showed that the electronic tongue combined with multivariate statistical analysis can be used to evaluate taste of TCM, at the same time, it could provide a fast and simple method for identifying different processed products.