Latest ArticlesA new rapid, quality control method based on quantitative water tests has been established for the quality evaluation of Indigo Naturalis. The Turbiscan stability index (TSI) of 26 batches of Indigo Naturalis was measured by a stability analyzer. The parameters, including the method by which the ingredients are added, their particle size, amount, and the testing temperature, were systematically optimized and the methodological indexes such as repeatability and stability were determined. The content of indigo and indirubin in 26 batches of Indigo Naturalis was determined by high performance liquid chromatography and the total ash was measured. The correlation analysis between the active ingredients, total ash content and TSI value of Indigo Naturalis was determined by SPSS 26.0 and Origin 2021. This research shows that the best way to prepare samples for testing is to add 0.2 g of Indigo Naturalis powder which has passed through a No. 7 sieve but failed to pass through a No. 9 sieve to a glass bottle containing 20 mL pure water by a funnel and scan at 25 ℃ with a stability analyzer. Consistency analysis showed that the content ranking of indigo and indirubin is opposite to the TSI value, and the content ranking of total ash is generally consistent with the TSI value. Correlation analysis showed that the correlation coefficients of indigo and indirubin content and TSI value were -0.850 and -0.801, respectively, and R2 was 0.72 and 0.64. The correlation coefficient between total ash content and TSI value was 0.724, R2 was 0.52. Using the change in TSI value of Indigo Naturalis powder in water, this study establishes the range of classification of Indigo Naturalis decoction pieces and the content of relevant components, which can be used to authenticate Indigo Naturalis and evaluate its quality.
Galli Gigerii Endothelium Corneum (GGEC) is a commonly used traditional Chinese medicine for digestion. Its odor is unpleasant, which decreases children's compliance with taking this traditional medicine. Traditional processing methods utilize heat processing methods such as stir-frying and vinegar processing to deodorize the medicine, but this affects the activity of digestive enzymes, so there is a need to find a new method for removing the fishy odor while retaining the beneficial effect of GGEC. Here we have developed the use of supercritical CO2 low-temperature fluid extraction to eliminate the odor while retaining the medicinal benefits. Headspace-solid-phase microextraction-gas chromatography-triple quadrupole mass spectrometry (HS-SPME/GC-QQQ-MS/MS) combined with the gas activity value method was used to determine compositional differences in the product before and after supercritical CO2 extraction and separation. Then, based on the sensory evaluation of volunteers, combined with the analysis of volatile components, the fishy odor intensity and the types of fishy odorants were compared between the raw product, stir-fried product, vinegar product and the supercritical CO2 extract. Pepsin and amylase activity were used to compare the differences in the digestive enzyme activities with the four forms of GGEC, and Fourier transform infrared spectroscopy (FT-IR) was used to compare the differences in the structure. We compared the content of total amino acids, digestive amino acids and bitter amino acids, and an animal model of delayed gastric emptying in mice with soybean oil, based on a phenol red indicator, was used to determine differences in the efficacy of gastric emptying in vivo. The results show that the fishy odor of GGEC powder is significantly reduced after supercritical extraction, and the substances that contribute the fishy odor are only 12.8% of the raw material. The results of FT-IR analysis show that the supercritical extract of GGEC is not changed in its material structure compared with the raw product. The digestive enzyme activity titers showed that amylase and pepsin activity in the raw products are about 3.9 and 1.4 times higher than those of stir-fried products and vinegar products. The activity titers of amylase and pepsin in the supercritical CO2extracts are about 2.7 and 1.3 times higher than those of stir-fried products and vinegar products, and there was no significant difference in the content of digestive-promoting amino acids in the four types of GGEC. The in vivo validation experiment showed that the average gastric emptying rates of the mice in the raw product group, the supercritical extract group, the stir-fried product group, and the vinegar product group were 69%, 59%, 40% and 51%, respectively. Compared with the stir-frying method and the vinegar-simmering method, the supercritical CO2 fluid extraction method retained the gastric emptying effect of GGEC. In general, the supercritical CO2 fluid low-temperature extraction method removes the fishy odor of GGEC as compared with the traditional stir-frying method and vinegar method, and retains the biologically active components and the effect on digestion of GGEC.
Acute lung injure (ALI) is a severe diffused lung disease, which is caused by pathogen-induced infections, inhalation of irritates, and so on. It could lead to acute respiratory distress syndrome (ARDS). Long oil (LO) is a lipidic mixture extracted from multiple medicinal animals and plants. It has been used for clinical wound repair. Here, an O/W LO emulsions (LOE) was prepared, which was composed of LO, Tween-80, propylene glycol, xanthan gum, and water. The droplet size of LOE was 671.63 ± 7.21 nm, and the zeta potential was-17.8± 1.26 mV. The size of LOE was small and homogenous, and the stability was satisfied. The aerosols had an aerodynamic diameter of 2.25 ± 0.05 μm after atomization of LOE with a vibrating screen atomizer, where the percentage of particle sizes within 1-5 μm was 81.40%, indicating effective deep lung deposition and suitable pulmonary inhalation. The safe dose of LOE was high to 12.50 μg·mL-1 on human embryonic lung fibroblast MRC-5 cells. In the range of 0.02-2.50 μg·mL-1 of LOE, the proliferation and migration of mouse fibroblast L929 cells were improved. Animal experiments were approved by the Ethics Committee of Institute of Radiation Medicine, Academy of Military Medical Sciences, and the experiments were conducted by relevant guidelines and regulations. No significant toxicity was observed after intratracheal (i.t.) administration of LO (3.25 mg·kg-1) to mice. Mouse i.t. administration of LOE remarkably attenuated lung injury induced by lipopolysaccharide with mitigations of inflammatory factors (tumor necrosis factor-α, interleukin-6) and total proteins. LOE is a promising inhaled formulation for the treatment of ALI.
Lysine decarboxylase is a key enzyme involved in the upstream biosynthesis of lycopodium alkaloids (LAs) such as huperzine A, contributing to the decarboxylation of lysine to 1, 5-pentanediamine (cadaverine). Three lysine decarboxylase genes (HsLDC-L1, HsLDC-L2, HsLDC-L3) were successfully cloned from Huperzia serrata using transcriptomic sequence data mining strategy combined with reverse transcription PCR. The physicochemical properties, secondary and tertiary structures, amino acid identities, and evolutionary relationship of the three LDCs were analyzed by online bioinformatics analysis platforms and DNAMAN, MEGA 7.0 software, revealing that all of these proteins had the conserved PLP binding domain and active site residues were completely conserved in LDCs. Phylogenetic analysis showed that these LDCs were located in the same branch as other known LDCs from LA-producing plants. Accordingly, the ORFs of these three HsLDCs were inserted into different expression plasmids for further expression in E. coli. However, only HsLDC-L1 was successfully expressed in E. coli BL21 (DE3) by inserting into a pCold TF vector. The recombinant protein was purified by Ni2+ affinity chromatography purification. HsLDC-L1 contains 469 amino acid residues, with a calculated molecular weight of 50.50 kDa. HsLDC-L1 expectedly catalyzed the decarboxylation of lysine to produce cadaverine. In addition, HsLDC-L1 can also catalyze the generation of putrescine from ornithine. However, it cannot catalyze the decarboxylation of tyrosine, phenylalanine, tryptophan and histidine. The results not only provide insight into the biosynthesis of LAs including huperzine A, but also provide a critical genetic element for the overproduction of Δ1-piperideine and pelletierine, the essential biosynthetic precursors of LAs, using synthetic biology strategies.
New drug research and development is a technology-intensive industry with high investment, high cycle and high risk. In recent years, with the rapid development of modern disciplines such as omics technology, bioinformatics, high-throughput and high-content screening, and artificial intelligence, the research and development of small-molecule drugs has presented a new paradigm characterized by "integrated medicinal chemistry". This review summarizes new enabling drug discovery technologies, the emergence of new subfields formed through integration innovations and practical chemistry toolbox in the field of medicinal chemistry.
At present, majority of the small molecular drugs used in clinics target proteins, they exert the efficacy through the binding to specific sites on the target protein. However, the "druggable" protein targets account for a small portion of the total number of proteins, and "non-druggable" proteins account for 80%, because of not having suitable drug binding sites. In the central rule, RNA is located in the upstream of proteins and controls the transcription of proteins. The research of small molecule drugs targeting RNA can solve the problem of protein "undruggable proteins" in some extent. This review summarizes the representative research achievements of small molecular drugs targeting RNA in recent years, and the screening methods applied to this field, with the focuses on the latest progress of small molecular drugs targeting novel coronavirus RNA.
The overexpression of doublecortin-like kinase 1 (DCLK1) is closely related to the occurrence and development of various malignant tumors. Discovery of novel anti-tumor agents targeting DCLK1 represents a hot spot in this field. So far, several DCLK1 small molecule inhibitors with excellent anti-tumor activity in vitro and in vivo have been designed and synthesized, which is expected to provide a new strategy for tumor therapy. This article reviews the research progress in the discovery, structure type, structural optimization, biological activity and mechanism of action of DCLK1 small molecule inhibitors, and provides research basis for the development of new anti-tumor small molecule inhibitors targeting DCLK1.
Heterotrimeric G proteins are classes of signal-transducing proteins that bind to guanine nucleotides and possess GTP hydrolase activity. G proteins are composed of three subunits α, β, and γ, and are considered as the "molecular switch" in the GPCR signaling pathway. The abnormal activation of G protein is strongly related to diseases such as uveal melanoma, asthma, et al., making directly targeting G protein as an promising strategy for combating diseases. In this review, the classification and physiological functions of G protein are briefly described, and the research progress of G proteins in diseases, G protein modulators are reviewed.
Oxidative stress is a redox imbalance in the body, which is one of the important factors leading to tissue damage and diseases. The nuclear factor E2-related factor 2 (Nrf2)-Kelch like ECH-associated protein 1 (Keap1) signaling pathway is not only an important defense system against oxidative damage, but also one of the key signaling pathways of the antioxidant capacity. Numerous studies have shown that targeting the Keap1-Nrf2 signaling pathway to activate Nrf2 has become an effective strategy for the treatment of oxidative stress and related diseases. Using small molecules to directly block the Keap1-Nrf2 protein-protein interaction (PPI) is one of the important directions for activating Nrf2 and exerting the cytoprotective effect, which can avoid the potential side effects of covalent modification of Nrf2. On the other hand, the Keap1 is an efficient E3 ubiquitin ligase that has been used in the design of proteolysis targeting chimeras (PROTACs). This review summarizes the research progresses of Keap1-Nrf2 protein interaction inhibitors and degraders based on the Keap1 E3 ubiquitination system in recent years.
Lysine-specific demethylase 1 (LSD1) plays vital roles in cell stemness, differentiation, cell motility, metabolic control and epithelial-mesenchymal transition, which is closely associated with tumorigenesis processes including cell proliferation, invasive, metastasis and poor prognosis. Besides, LSD1 also contributes to the occurrence of other diseases such as neurodegenerative diseases and viral infections. Since 2013, the irreversible inhibitors including tranylcypromine, ORY-1001, ORY-2001, GSK-2879552, IMG-7289, INCB059872, TAK-418, LH-1802 and reversible inhibitors including CC-90011 and SP-2577 have been approved for clinical assessment. This review comprehensively summarizes the clinical research of LSD1 drug candidates and briefly discusses the prospects, opportunities and challenges of LSD1-targeted drug discovery, aiming to provide a landscape for the related drug development.