Actinobacteria remain to be one of the major sources for new antibiotics, which historically play an essential role in human's fight against infectious diseases. Due to the emergence of resistant pathogenic microorganisms such as bacteria, fungi and viruses, it is imperative to develop new and effective drugs against these pathogens. The symbiotic actinobacteria residing inside the animals are becoming more and more important as a new source for drug discovery, as well as a "hotspot" in the field of microbial medicine. During the long period of evolution, a specific host-microbe mutualism is formed between the symbiotic bacteria and their hosts of animals. In this unique ecosystem, the secondary metabolites produced by bacteria are well tolerated by the hosts, meanwhile, are able to selectively suppress pathogenic microorganisms, thus providing a specific protection to their hosts. These secondary metabolites encompass a large variety of structural diversities of natural products, and so far, the reported biological activities are including antibacterial, antifungal, antiviral, antitumor, and immunomodulatory effects, which give them a great potential in the field of drug discovery. Herein, we review the secondary metabolites of animal symbiotic actinobacteria and their biological activities within the recent decade, by which to provide a viewpoint for future research of drug discovery from actinobacteria.

In this study, rats were used to evaluate the effect of Radix glycyrrhiza on reducing liver toxicity of Tripterygium wilfordii. Metabonomics techniques were used to analyze the changes of small molecular metabolites and the metabolic pathways involved in the beneficial process. Different groups of rats were given for the extractions from Tripterygium wilfordii and Tripterygium wilfordii together with Radix glycyrrhiza. The general state, pathological changes of liver tissue, biochemical indexes of liver function and the changes of inflammatory factors in rats were observed. The results showed that the liver tissue injury of Tripterygium wilfordii group was significant, and the injury was reduced by Radix glycyrrhiza. Biochemical indexes and inflammatory factors also suggested that Tripterygium wilfordii together with Radix glycyrrhizaeffectively decreased the liver toxicity. HPLC-MS/MS-IT-TOF was used to characterize the difference of serum metabolism in rats. Multivariate statistical analysis was used to screen 15 potential biomarkers, such as fatty acid, glycerol ester, glycerol phosphate, phosphatidylethanolamine and phosphatidylcholine. It mainly involved in 7 metabolic pathways, such as glycerol phospholipid metabolism, linoleic acid metabolism, alpha linoleic acid metabolism, and glycosyl phosphatidylinositol terminal biosynthesis. The results showed that the Tripterygium wilfordii compatibility of Radix glycyrrhizaeffectively decreased the liver toxicity induced by Tripterygium wilfordii. Phospholipid metabolism may be the key metabolic pathway of Tripterygium wilfordii hepatotoxicity and the target of Radix glycyrrhiza. This study provides a reference for the control of liver toxicity of Tripterygium wilfordii.

In this study, the three dimensional(3D)organoid culture system was established by liquid overlay method, and applied as an effective model to evaluate the hepatic injury of susceptible compounds in Polygonum multiflorum Thunb. Compared with the ordinary two dimensional(2D)culture of liver cells, the albumin expression of L02 cells and HepG2 cells were increased by 2.5 and 6.7 times in the 3D organoid culture system, respectively. After the cultivation of 21 days, urea generation levels of 3D culture were increased by 8.3 and 15.5 times. More importantly, HepG2 cells were more suitable to development of organoids than L02 cells. The gene expressions of phase Ⅰ and Ⅱ drug metabolism enzymes of HepG2 cells cultured as 3D organoids were significantly increased than that in 2D culture, such as the fold changes of CYP2C9 was up to 381.9, CYP3A4 to 87.0, CYP2D6 to 312.6. In addition, drug transporter relative genes were also up-regulated. The results demonstrated that the liver synthesis and metabolic function of the 3D model were better than that of the 2D cultured hepatocytes. The results of hepatotoxicity evaluation showed this developed model can be used to assess the hepatotoxicity of acetaminophen and other positive control drugs, which were considered with defined hepatotoxicity. On the 3D culture model, the IC₅₀ value of repeated drug dose administration was significantly lower than that of single dose administration. However, the IC₅₀ of 2, 3, 5, 4'-tetrahydroxy-cis-stilbene-2-O-β-glucoside(cis-SG), which is the susceptible compound in Polygonum multiflorum Thunb., could not be detected in 2D cultured model. With the treatment of a single dose administration in organ 3D culture model, the IC₅₀ of cis-SG was 1.9 times than that of cyclosporine A, and the IC₅₀ of 2, 3, 5, 4'-tetrahydroxy-trans-stilbene-2-O-β-glucoside(trans-SG)was 4.1 times than cis-SG. The hepatotoxicity results of cis-SG and trans-SG on the 3D cultures were similar to in vivo toxicity results obtained in previous work. On organ 3D culture model, the IC₅₀ of cis-SG with repeat of administration decreased compared with that with single dose administration, suggesting that long-term medication may increase the risk of liver injury. In summary, the 3D organoid culture system can be used for a long period to preserve the capacity of liver synthesis and metabolism. The organoids were a model suitable for evaluation of mechanism of the drugs with low toxicity.

This study was designed to establish the method of characterization of surface free energy(SFE)and evaluate the compaction properties of pharmaceutical materials based on SFE. We investigated the contact angles of materials with water and diiodomethane under different compression pressures. The contact angles of materials at 353 MPa compression pressure were utilized to calculate the related parameters of SFE ultimately. The area under tensile strength-compression pressure curve(AUTSC)and pressure yield(Py)were employed to evaluate the compactibility of material. Additionally, Pearson correlation analysis was utilized to analyze the relationship between the SFE and the compaction properties of pharmaceutical materials. The results exhibited that SFE had a significant correlation with the compaction properties of materials(P < 0.05). Moreover, the related parameters of SFE, i.e., cohesive work(W_co)and polarity index(PI)of SFE, were positively correlated with Py of Heckel equation and negatively related with AUTSC. The higher values of W_co and PI, the stronger repulsive force among the particles, led to a worse compaction behavior. In this study, we established the method for characterization of the compaction behavior of materials based on SFE initially. This study also demonstrated that SFE could evaluate the compaction behavior effectively, which provides a better understanding of compaction behavior for pharmaceutical researchers.

The drug hepatotoxicity assessment method in vitro was established by 3D organoid model of HepaRG cell line in combination with high content imaging analysis. HepaRG cells were differentiated into hepatocyte-like morphology and bile canaliculus-like structures by treatment with hydrocortisone and dimethyl sulfoxide(DMSO), inducing the expressions of drug-metabolizing enzymes, transporters, nuclear receptors and hepatocyte-specific protein albumin(ALB)genes, finally forming the stable organoids with closely resembling liver function in vitro. Through the high content imaging analysis and the specific, multi-targets fluorescent dye, the number of live/dead cells, mitochondrial membrane potential(MMP), intracellular reactive oxygen species(ROS)were analyzed for the drug hepatotoxicity evaluation. The results showed that the organoids evaluation model of HepaRG cells in vitro could be used to assess accurately the difference between hepatotoxicity positive control drugs of amiodarone(AMD), cyclosporin(CSP)and the negative control drug of aspirin(ASP): AMD and CSP concentration-dependently decreased the number of total and live organoid cells. The number of dead organoid cells was increased sharply when the concentration of AMD was more than 50 μmol·L^-1, while no significant changes was observed for ASP. AMD and CSP concentration-dependently caused the MMP declined and the ROS increased, with AMD showing a greater degree than CSP and ASP presenting no markedly effect. In conclusion, the organoid evaluation method of HepaRG cells in combination with high content imaging analysis can be used for the drug hepatotoxicity assessment in vitro. It displays the advantages of multi-target, high throughput, intuitive results as well as quantitatively.

This study was designed to investigate the effect of 2, 3, 5, 4'-tetrahydroxystilbene-2-O-β-D-glycoside(TSG)on hypoxia/reoxygenation(H/R)-induced oxidative stress injury and its potential mechanism in human bronchial epithelial cell(BEAS-2B)cells. BEAS-2B cells were exposed to H/R treatment. Level of intracellular ROS was detected using DCFH-DA probe and fluorescence microplate reader. Production of MDA and activity of SOD were evaluated with MDA and SOD kits. Nucleus was shaped by DAPI staining. Translocation of Bax to mitochondria was observed in MCF-7/GFP-Bax cells. Change in mitochondrial membrane potential was detected by JC-1 staining. Release of cytochrome C from mitochondria was detected by immunofluorescence. Expressions of mitochondrial/cytoplasmic Bax and cytochrome C, caspase-9, caspase-3, phosphorylated MAPK, HIF-1α and phosphorylated p53(p-p53) were determined by Western blotting. TSG significantly improved cell viability and reduced H/R-induced ROS production in BEAS-2B cells, while significantly decreased MDA production. It inhibited Bax translocation and nucleus fracture, reversed the decrease in mitochondrial membrane potential and inhibited the release of cytochrome C and following activation of caspase-9/caspase-3. Simultaneously, TSG down-regulated the signals of SAPK JNK1/2 and p38 MAPK without an impact in ERK1/2. It attenuated expression of HIF-1α and phosphorylation of p53. This study suggests that TSG could protect BEAS-2B against H/R-induced apoptosis, perhaps through the MAPK, HIF-1α and p53 pathways.

The objective of this study was to examine the antimetastatic effects of cordycepin and elucidate its molecular mechanism using MHCC97H cells in vitro and in vivo. Cellular proliferation was detected with MTT assay. The migration and metastatic potential were measured with scratch wound healing as well as transwell migration assays in vitro. Protein expression was detected by Western blotting. Antitumor and antimetastatic effects of cordycepin were evaluated by subcutaneous xenograft and lung metastatic model in vivo. The results demonstrated that cordycepin significantly inhibited MHCC97H cells proliferation and metastasis which was due to the down-regulation of AKT, p-AKT, p-GSK-3β, β-catenin, N-cadherin, MMP-7, MMP-9 and up-regulation the expression of E-cadherin. Furthermore, cordycepin inhibited tumor growth and metastasis in a dose-dependent manner in vivo. Cordycepin(40 and 20 mg·kg^-1)and 5-fluorouracil group significantly inhibited the tumor weights to 0.38 ± 0.04, 0.61 ± 0.08 and 0.65 ± 0.07 g, respectively, comparing with the control group(1.52 ± 0.46 g)(P < 0.01), but not 10 mg·kg^-1 cordycepin group(1.13 ± 0.36 g)(P > 0.05); the lung metastasis nodus numbers showed the same results, which in all group above(48.9 ± 7.2, 67.2 ± 9.4, 73.6 ± 8.6, respectively)were fewer than the control group(123.5 ± 14.5)(P < 0.01), except 10 mg·kg^-1 cordycepin(106.4 ± 11.3)(P > 0.05). Collectively, cordycepin inhibited MHCC97H cell proliferation and metastasis in vivo and in vitro.

To investigate the effects of peroxisome proliferator-activated receptor gamma(PPAR-γ)on the liver injury of Polygonum multiflorum, we established a model of immunological idiosyncrasy liver injury induced by lipopolysaccharide. The 70 Sprague-Dawley(SD)rats were randomly divided into control group, LPS group(2.8 mg·kg^-1), PM group(crude drug, 2.16 g·kg^-1), PPAR-γ agonist group(pioglitazone, 0.5 mg·kg^-1), PM+LPS group(crude drug 2.16 g·kg^-1, 2.8 mg·kg^-1), PPAR-γ agonist+LPS group(0.5 mg·kg^-1, 2.8 mg·kg^-1)and PM+LPS+PPAR-γ agonist group(crude drug, 2.16 g·kg^-1, 2.8 mg·kg^-1, 0.5 mg·kg^-1). The rats were orally given PM, once a day for consecutive 2 days. The control rats were given the same amount of distilled water. Liver injury was induced by intravenous injection of LPS. Sodium pentobarbital was injected intraperitoneally for anesthesia, and liver samples were collected together with blood. The plasma levels of alanine transaminase(ALT), aspartate aminotransferase(AST), tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6) and interferon-γ(IFN-γ)were measured. Pathological changes and hepatocellular apoptosis were examined by liver biopsy, and immunohistochemical observation of liver tissue expression of PPAR-γ and NF-κB p65. A negative correlation was observed between the expression of PPAR-γ in hepatic tissue and liver injury of Polygonum multiflorum. PPAR-γ agonist significantly reduced the PM-induced idiosyncratic liver injury in rats according to serum ALT and AST(P < 0.05), reduced liver pathological injury and hepatocyte apoptosis, decreased serum TNF-α and other inflammatory cytokines(P < 0.05), liver tissue PPAR-γ expression, and inhibited expression of NF-κB p65(P < 0.05). The results suggest that the occurrence of immunological idiosyncrasy liver injury of PM is related to inhibition of the PPAR-γ pathway and elevation of inflammatory factors. PPAR-γ agonist can reverse the idiosyncratic liver injury induced by PM, and provide a reference for elucidating mechanism of idiosyncratic liver injury induced by Polygonum multiflorum.

An ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF/MS)method has been established to analyze the bioactive components of the aqueous extract of Euodiae Fructusand detect the metabolites in rats after oral administration of the aqueous extract. Compounds were detected by analyzing their retention times, high resolution mass data, mass spectra and comparing with the reference substances. As a result, 27 compounds were characterized from the aqueous extract of Euodiae Fructus, and 25 compounds were identified on the basis of the reference substances. 16 parent compounds and 35 metabolites were detected in rats' plasma, urine and feces samples, and all of the parent compounds were determined unambiguously through comparison with the reference substances. Four classes of compounds were identified from the aqueous extract of Euodiae Fructus, including phenolic acids, limonins, flavonoid glycosides and alkaloids. Phenolic acids, flavonoid glycosides and alkaloids were detected in rats' plasma, urine and feces, while limonins were detected in the urine and feces. The main metabolism pathways of these compounds in rats might include hydroxyl, hydrogenation, methylation, sulfating, glucuronidation, and so on. The results of this study provide references in the material basis of Euodiae Fructus in vivo.

A series of novel xanthones with terminal amine substituents at xanthone's C3 and C6 positions were designed and synthesized as potential ligands for telomeric G-quadruplex DNA. All the compounds in this series were bound to telomeric G-quadruplex in a "thread intercalation" manner that illustrated both in molecular docking and spectrometric studies. Among them, 10c and 10d showed better binding abilities and specific affinity toward G-quadruplex DNA HTG21 over ctDNA in the fluorescence assay. The antiproliferative activities of four screened compounds were examined in three cancer cells by MTT in vitro, and their inhibitory effects were observed at low micromolar ranges. In addition, the PCR stop assay demonstrated that 10c and 10d effectively inhibited the amplification ability of telomerase.