UDP glucosyltransferase (UDPGT) catalyzes the synthesis of secondary metabolites and plant hormones to regulate plant growth and development, pathogen defense and environmental adaptability. In this study 18 members of the RcUDPGT gene family were cloned from Tibetan Rhodiola crenulata and analyzed using bioinformatics. The tissue-specific expression, abiotic stresses and plant hormones (abscisic acid, auxin, methyl jasmonate) induced expression patterns were identified by real-time quantitative PCR. The bait vector of RcUDPGT (JX228125.1) was constructed to select interacting proteins from an Arabidopsis yeast library. The results of the bioinformatics analysis revealed that RcUDPGT nucleotide sequences were about 1 400 bp and encoded 452-498 amino acids. In the primary protein sequences, C-terminal sequences were more conserved compared with N-terminal regions, which held a PSPG (plant secondary product glycosyltransferase) domain. In the tertiary structures, RcUDPGTs contained a UDP sugar donor recognition binding site. In addition, all genes had multiple phosphorylation sites. The results of qRT-PCR showed that RcUDPGTs genes were expressed in root, stem and leaf. The expression levels were regulated by low temperature/ultraviolet light and various plant hormones (ABA, IAA, MeJA), but the expression patterns were quite different among them. For example, RcUDPGT6, RcUDPGT11, and RcUDPGT17 had the highest expression in leaves and were induced by all three hormones, suggesting that the functions of these genes might be to respond to environmental changes. RcUDPGT9, RcUDPGT10, RcUDPGT14 were most abundantly expressed in roots and were significantly induced by ABA and MeJA hormones, indicating that these genes may be involved in the synthesis and accumulation of salidroside. Yeast two-hybrid results showed that RcUDPGT did not exhibit autoactivation and cell toxicity, and two significant interactional genes were identified, AtKCR1 (AT1G67730.1) and AtSNL4 (AT1G70060). The AtKCR1 gene encodes a β-ketoacyl reductase (KCR) involved in synthesis of very long chain fatty acids. The AtSNL4 gene encodes a homolog of the transcriptional repressor SIN3, which could participate in the ABA hormone signaling pathway and enhance the transcriptional repression of AP2/EREBP class factors in Arabidopsis. These results suggest that the accumulation of the secondary metabolite salidroside in Rhodiola crenulata might be affected by several regulatory mechanisms. The above results may lay the foundation for understanding the adaptive mechanism of Rhodiola crenulata in a high altitude environment and stimulate an in-depth study of the synthesis and accumulation of secondary metabolites in this species.

This research explored the synergistic effects and the potential mechanisms of RCE-4 and various nonsteroidal anti-inflammatory drugs (NSAIDs) on the proliferation of cervical cancer Ca Ski cells. The MTT assay and CalcuSyn V2.0 software were used to detect cell proliferation and calculate the combination index (CI); the expression levels of various proteins were analyzed using Western blot assay; mitochondrial membrane potential (MMP) was assessed using JC-1 staining; acridine orange/ethidium bromide (AO/EB) double-fluorescence staining was used to detect the apoptosis of Ca Ski cells; a co-immunoprecipitation (Co-IP) assay was used to analyze the relative content of Bcl-2-Beclin 1 complex in Ca Ski cells. The results demonstrate that the combination of RCE-4 and NSAIDs increases the inhibition of Ca Ski cells compared to the single-RCE-4 group, and celecoxib provided the best synergistic effect among the four NSAIDs tested, with a CI of 0.32. The combination of RCE-4 and celecoxib significantly down-regulated the expression of cyclooxygenase-2 (COX-2) and nuclear transcription factor-κB (NF-κB), and promoted the expression of non-steroidal anti-inflammatory drugs activity gene-1 (NAG-1). In addition, autophagy induced by RCE-4 was markedly inhibited in combination with celecoxib, which was associated with down-regulation of the expression of microtubule-associated protein 3 (LC3)-Ⅱ, Beclin 1, p62 and autophagy-related gene (ATG) 3/4B/5/7/14. RCE-4-induced apoptosis was significantly enhanced by altering the depolarization of mitochondrial membrane potential and the expression of B cell lymphoma-2 (Bcl-2), B cell lymphoma-xl (Bcl-xl), Bcl-2 associated X protein (Bax), Bcl-2/Bcl-xl-associated death promoter (Bad) and cleaved cysteinyl aspartate specific proteinase (cleaved-caspase) 3/7/9. Furthermore, the formation of the Bcl-2-Beclin 1 complex was significantly inhibited in Ca Ski cells treated with RCE-4 in combination with celecoxib. Taken together, this research shows that the combination of RCE-4 and celecoxib has a significant synergistic effect on the proliferation of Ca Ski cells by promoting apoptosis, inhibiting autophagy and disturbing the formation of the Bcl-2-Beclin 1 complex, which may be a novel strategy to increase the sensitivity of anti-cervical cancer drugs.

1-Deoxy-D-xylulose-5-phosphate synthase (DXS) is a rate-limiting enzyme involved in the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for terpenoid precursor biosynthesis. DXS plays an essential role in glycyrrhizic acid (GA) biosynthesis. Based on our previous transcriptome study, there was a negative correlation between DXS expression and GA content. Therefore, we explored the regulatory role of DXS in GA biosynthesis using both gene overexpression and gene knockout in a hairy root culture system. DXS was cloned from Glycyrrhiza glabra L. (GenBank Accession No. MN158121). A plant binary expression vector pCA-DXS was constructed by a gene fusion method. The sgRNA sequence was designed based on the first exon of DXS to construct the gene editing vector pHSE-DXS. Hairy roots overexpressing or knocking out DXS were generated through an Agrobacterium-mediated method with licorice hypocotyls as explants. Wild-type hairy roots and negative control hairy roots containing empty plasmids were also evaluated. UPLC was used to determine the GA content in each licorice hairy root line. Results showed that the content of GA in the hairy root group knocking out DXS was significantly higher than that in the wild-type and negative control groups, while in the hairy root group overexpressing DXS was significantly lower, suggesting that DXS plays a negative role in GA biosynthesis. This study provides a foundation for determining the function of DXS in terpenoid metabolism and for further establishment of a molecular regulatory network of GA biosynthesis.

As a key signal transduction molecule involved in the innate immune response, stimulator of interferon genes (STING) is triggered by cytosolic DNA from pathogen and host origins, and plays an important role in inducing the secretion of type Ⅰ interferons and proinflammatory cytokines, thereby defending against viral and intracellular bacterial infections and regulating the production of spontaneous antitumor immune responses in vivo. Thus, STING agonists have shown useful therapeutic effects for pathogen infection and cancer. In the past decade research on STING and its agonists has progressed rapidly. Here, we summarize recent advances in the structure and activation of STING and the mechanism of the cGAS-STING pathway. In particular, we review research advances of STING agonists, analyze the crystal structure of STING in complex with its agonists and the structure-activity relationship of STING agonists, and summarize the strong challenges of developing STING agonists.

Gentiana crassicaulis Duthie ex Burk. in Gentiana (Sect. Cruciata), Gentianaceae, is one of the original plants of both Gentianae Macrophyllae Radix and Tibetan herb Jie-Ji Na-Bao, which contain such bioactive iridoids as gentiopicroside, loganic acid and others. In this study, based on previous work, the transcriptome of G. crassicaulis was sequenced and analyzed to construct transcriptome databases of roots, stems, leaves and flowers. qRT-PCR verification was conducted for parts of unigenes that may be key enzymes in the pathway of iridoid biosynthesis. The results are as follows: ① a total of 159 534 unigenes were obtained, with an average length of 679 bp. According to the functional classification of GO, unigenes can be divided into 3 categories with 67 branches. The unigenes were aligned in the KOG database and were classified into 25 categories according to function. ② In the KEGG database, 215 unigenes were implicated in 20 standard secondary metabolism pathways. The analysis shows that 305 unigenes encoded 28 key enzymes in the pathway of iridoid biosynthesis, and their expression in different organs is different; and ③ qRT-PCR was approximately consistent with RNA-Seq results. The 7 annotated unigenes identified in this study, HMGS, DXS, MCS, GPPS, G10H, 7-DLNGT and STR, all had higher relative expression levels in the above-ground parts (stem, leaf and flower) than in the underground part (root). Iridoids are common active and index components of such traditional Chinese medicines as Qinjiao, Longdan, Dangyao, and Qingyedan, among others. Therefore, this work provides basic scientific data for further development including obtaining active components or intermediates through biotechnology, exploring the accumulation of effective components, evaluating the quality of different ecotype varieties, and identifying authentic biosynthesis pathways of medicinal materials.

Nanocrystal drugs have many advantages, such as no carrier materials, easy industrialization, diversified dosage forms, and can significantly improve the solubility and bioavailability of insoluble drugs, so many drugs have been on the market. The traditional nanocrystal preparation technology has the problems of low preparation efficiency and process limitation of the smallest achievable particle size. With the progress of pharmaceutical preparation technology, the preparation technology of nanocrystal drugs is constantly improving, and new preparation technologies are constantly emerging. The emergence of new technologies has greatly shortened the process time and makes it possible to prepare nanocrystal drugs with smaller particle diameters. In this paper, the preparation technologies of nanocrystal drugs, especially the new preparation technologies such as high gravity controlled precipitation, microfluidic reaction technology and various combination technologies, are reviewed from three aspects: "Top-down" technology, "Bottom-up" technology and combination technology. This article also prospects the development of new preparation technologies, hoping to provide reference for the related research of nano-preparations.

In this study, a rat morphine drug discrimination model with a fixed ratio (FR) of 10 (FR10) was established using different methods to explore which methods can shorten the modeling time and test the dose-response relationship and median effective dose (ED₅₀) value. Animal welfare and experimental procedures are in accordance with the provision of the Animal Ethics Committee of Shanghai InnoStar Bio-tech Co., Ltd. Forty rats were initially shaped to press lever under a fixed-ratio schedule of food reinforcement. The animals that were successfully trained under a FR10 schedule of food reinforcement were divided into two groups, namely the single-lever + double-lever training group 1 and the double-lever training group 2. In each group, rats were trained to discriminate morphine at 5.6 mg·kg^-1 from saline by the intraperitoneal route. After training, different doses of morphine were used to substitute for training dose of morphine, the dose-response curve for morphine were identified in rats, and the ED₅₀ value was calculated. The results showed that, in food training phase: 34 rats successfully entered the discrimination training during food training; in discrimination training phase: 14 animals in group 1 met the discrimination training standard for the first time, which took about (40.71±2.93) days, and there were 13 animals in group 2 that met the discrimination training criteria for the first time, and it took about (51.15±2.55) days. It can be seen that the method of single-lever + double-lever training is better than single-lever training, and the difference is significant compared with group 1 (P < 0.05); in generalization test phase: there are 17 rats completed morphine generalization test, and the percentages of morphine-lever responses produced by the generalization test of different doses of morphine (0, 0.1, 0.5, 1, 3, 5.6, and 10 mg·kg^-1) were (9.56±3.13)%, (9.01±5.83)%, (13.82±7.95)%, (29.04±10.13)%, (41.70±10.65)%, (85.36±7.16)%, (94.56±2.76)%, respectively. The results showed that the discriminative stimulative effect induced by morphine dose between 0-10 mg·kg^-1 increased in a dose-dependent manner, producing a good dose-response curve, and the ED₅₀ value of morphine was 4.74 mg·kg^-1 by linear fitting. The above results showed that, the FR10 morphine drug discrimination model has been successfully established using different methods; the single-lever + double-lever training method is better than the single-lever training, and can relatively shorten the discrimination training cycle.

ABC transporters on the intestinal barrier, blood-brain barrier and on tumor cells will affect drug bioavailability, transport across the blood-brain barrier and multidrug resistance. The active ingredients of traditional Chinese medicines can affect the function and expression of ABC transporters. When combined with pharmaceuticals the potential interaction between the two can change the efficacy of the medicines. We review the ABC transporter superfamily and their distribution with regard to their relationship and interactions with traditional Chinese medicine on the intestinal barrier and the blood-brain barrier, as well as their role in tumor multidrug resistance mediated by ABC transporters. We summarize the research progress over the past five years.

Resistance of tumor cells is a complex biological process involving multiple mechanisms and factors, in which anti-apoptosis is the most important cause of drug resistance. Previous studies have shown that the DNA binding activity of Runt related transcription factor 3 (RUNX3) increased prominently in Herceptin resistant gastric cancer cells (NCI N87R) while the relevance of which to drug resistance has not yet been confirmed. In this study, we employed CRISPR/Cas9 to establish RUNX3 knock-out cell line (△RUNX3/NCI N87R) to investigate the functions of RUNX3 in Herceptin resistance of NCI N87R cells and its potential mechanisms. We investigated proteomics profiling of △RUNX3/NCI N87R cells based on label free quantitative proteomics. Differentially expressed proteins were screened out according to fold change and significance level between △RUNX3/NCI N87R and NCI N87R cells. Pathway enrichment analysis was done using GeneAnalytics database, and gene ontology analysis was conducted by DAVID Bioinformatics Resources database. Protein-protein interaction networks were constructed based on STRING database. The results showed that △RUNX3/NCI N87R cells increased the sensitivity to Herceptin. Proteomic data demonstrated that the expression of 577 genes changed significantly in △RUNX3/NCI N87R cells, among which 191 genes were up-regulated while 386 ones down-regulated comparing with NCI N87R cells. Pathway analysis showed that autophagy, cell cycle, apoptosis, mitochondrial fatty acid β oxidation, neurogenic locus notch homolog protein 1 (NOTCH1), mammalian target of rapamycin (mTOR), Hedgehog and DNA damage response pathways exhibited notable changes based on pathway enrichment ratio and significance level (P < 0.05). These results indicated that RUNX3 knock-out altered multiple signaling pathways of NCI N87R cells. Western blotting manifested that the expression of autophagy regulatory molecules autophagy-related protein (ATG) 13, 7 and BECN1 increased remarkably while cell cycle molecules serine/threonine-protein kinase Chk2 (CHEK2) and apoptosis regulator Bcl-2 (BCL2) decreased prominently in △RUNX3/NCI N87R cells. The p-AKT expression decreased significantly in △RUNX3/NCI N87R cells compared with NCI N87R cells (P < 0.01) and was suppressed by Herceptin. These results indicated that RUNX3 knock-out altered cell cycle, increased inhibition to p-AKT by Herceptin, promoted autophagy and induced cell apoptosis of NCI N87R cells. These results suggested that RUNX3 may be a potential therapeutic target for reversing or reducing Herceptin resistance in gastric cancer cells.

The gut microbiota takes part in many in vivo important physiological activities of host, such as the substance metabolism and energy exchange, etc. The interaction between the host and the intestinal microorganisms has attracted scholars' attention. Flavonoids are a group of polyphenol compounds widely found in natural plants, with the bioactive effect of regulation of glucose and lipid metabolism, anti-inflammation. However, their low bioavailability cause difficulty to clarify the effective substances and the mechanism of flavonoids. Apart from the metabolic effects of liver on flavonoids, recent studies have shown that the gut microbiota can interact with flavonoids. On the one hand, flavonoids can be metabolized by gut microbiota and subsequent metabolites can produce pharmacological activities different from the parent components. On the other hand, flavonoids and their metabolites can in turn regulate the composition and physiological activities of the intestinal flora, which seems to provide a new insight for the research on the effective substances of flavonoids. In this review, we introduced the metabolic characteristics of flavonoids under the actions of intestinal bacteria, and the regulation effects of flavonoids on gut microbiota was also summarized. Meanwhile, the therapeutic effect of flavonoids under the action of intestinal bacteria was discussed.