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Aconicumines A–D, an advanced class of norditerpenoid alkaloids, and seven known alkaloids, were isolated from Aconitum taipaicum Hand.-Mazz. (Ranunculaceae). The structures of the previously undescribed compounds, including their absolute configurations, were fully elucidated based on spectroscopic and single-crystal X-ray diffraction data analysis. Aconicumines A–D exhibit interesting cage-like structure, characterised by an unprecedented N,O- diacetal moiety (C6–O–C19–N–C17–O–C7) that has not been previously observed in diterpenoid alkaloids. Possible biosynthetic pathways for aconicumines A–D were proposed. Aconitine, hypaconitine, and aconicumine A showed significant inhibition of nitric oxide production in RAW 264.7 macrophages induced by lipopolysaccharide with IC 50 values ranging from 4.1 to 19.7 μM compared to positive control (dexamethasone, IC 50 = 12.5 μM). Furthermore, the primary structure–activity relationships for aconicumines A–D were also represented. [Display omitted] • Four undescribed diterpenoid alkaloids (DAs) were isolated from Aconitum taipaicum. • All structures with their absolute configurations were completely determined. • Aconicumines A–D possessed rare 7,17-seco-DAs carbon skeleton in natural. • Aconicumines A–D presented an unprecedented N,O -diacetal residue in DAs. • Aconicumine A showed significant (nitric oxide) NO inhibitory activity. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is characterized by the accumulation of abnormal lymphoblasts in the bone marrow and blood. Though great progress has been made for improvement in clinical treatment during the past decades, some children with ALL still relapsed. Glucocorticoid (GC) resistance is an important clinical problem for ALL treatment failure. Therefore, further understanding of the mechanism of GC resistance and exploring novel therapeutic strategies are crucial for improving treatment outcome. The reported involvement of microRNAs (miRNAs) in drug resistance implied that deregulated miRNA expression might contribute to GC treatment response of ALL. However, individual miRNAs and their functional mechanisms potentially involved in the GC response are still largely unknown. In the present study, we found that miR-124 was up-regulated in prednisone insensitive human ALL cell line and prednisone-poor response ALL patients. Furthermore, it was found that miR-124 might contribute to GC resistance by promoting proliferation and inhibiting apoptosis of ALL cells. Importantly, we validated that miR-124, targeted and decreased the expression of glucocorticoid receptor (NR3C1), prevented the inhibitory effect of GC in ALL. These findings strongly suggest that miR-124 is critical in poor GC response and may serve as a potential therapeutic target in ALL with poor GC resistance. [ABSTRACT FROM AUTHOR]

To assess the role of the lateral triazine group of 2,6-bis(1,2,4-triazin-3-yl) pyridine (BTP) when coordinated to Am(iii), three tridentate N-donor ligands, i.e. BTP, 6-(-2-pyridyl)-2-pyridyl (hemi-BTP), and 2,2′:6′2′′-terpyridine (TPY), have been used to construct coordination complexes with Am(iii), and the structures and binding modes of these complexes have been investigated using the B3LYP functional. The 1 : 1 and 1 : 2 (metal : ligand) type complexes, based on our calculations, form mainly via reactions Am(H2O)3(NO3)3 + L → AmL(NO3)3 + 3H2O and [Am(H2O)6(NO3)2]+ + 2L → [AmL2(NO3)2]+ + 6H2O. The Gibbs free energy changes were in the order of TPY ＞ hemi-BTP ＞ BTP, independent of the presence of nitrate ions in the complexes. We show that in 1 : 1 type complexes substitution of electron-donating groups to the three ligands can enhance their binding ability. From analysis of NPA charge and Mayer Bond Order, it is found that the value of binding free energy is correlated with charge transfers between the central metal and the ligand: the larger the ligand-to-metal charge transfer, the more negative the binding energy, and meanwhile, the smaller the Mayer bond order of the Am–N bonds. This suggests that the interaction between Am(iii) and the tridentate ligands has a strong ionic feature, which is confirmed by the quantum theory of atoms-in-molecules (QTAIM) topological analysis. According to our calculations, the presence of the triazine group in BTP and hemi-BTP does not improve the binding affinity of the ligand to Am(iii), compared to TPY, but facilitates the ligand to adopt a conformation that favors to coordinate with Am3+ than others via a dynamic isomerization process, and the electron-donating groups on the triazine group may enhance the charge transfer between Am(iii) and the ligand, and thus stabilize the complex. We tentatively propose that the facile conversion between the conformations of BTP, which is more difficult for TPY and hemi-BTP, may significantly contribute to its higher affinity towards binding with Am(iii). [ABSTRACT FROM AUTHOR]

In this work, the equation-of-motion coupled-cluster approach with spin-orbit coupling (SOC) for ionization potentials (IP) at the singles and doubles level (EOMIP-CCSD) is employed to calculate spectroscopic constants of low-lying states of rare gas dimer ions Kr2+, Xe2+, and Rn2+. Two approaches are proposed to include contributions of triples: (1) energies of these states are calculated by adding the IPs from EOMIP-CCSD and the CCSD(T) energy of the rare gas dimers and (2) CCSD(T) energies without SOC for Rg2+ are first calculated and energies of these states with SOC are determined subsequently using the SOC matrix between these states. The first approach can provide accurate results for the three most stable states, while overestimates bond lengths for the other states. The second approach has been adopted previously and the SOC matrix element between 2Σ1/2+ and 2Π1/2 states was set to be [formula] times that of the SOC constant. In our work, the SOC matrix elements are determined from the calculated IPs and reasonable results for these states can be achieved with this approach, which could be useful for experimental works. [ABSTRACT FROM AUTHOR]

Indigo naturalis (IN) is a traditional Chinese medicine, named Qing-Dai, which is extracted from indigo plants and has been used to treat patients with inflammatory bowel disease (IBD) in China and Japan. Though there are notable effects of IN on colitis, the mechanisms remain elusive. Regarding the significance of alterations of intestinal flora related to IBD and the poor water solubility of the blue IN powder, we predicted that the protective action of IN on colitis may occur through modifying gut microbiota. To investigate the relationships of IN, colitis, and gut microbiomes, a dextran sulfate sodium (DSS)-induced mice colitis model was tested to explore the protective effects of IN on macroscopic colitis symptoms, the histopathological structure, inflammation cytokines, and gut microbiota, and their potential functions. Sulfasalazine (SASP) was used as the positive control. Firstly, because it was a mixture, the main chemical compositions of indigo and indirubin in IN were detected by ultra-performance liquid chromatography (UPLC). The clinical activity score (CAS), hematoxylin and eosin (H&E) staining results, and enzyme-linked immunosorbent assay (ELISA) results in this study showed that IN greatly improved the health conditions of the tested colitis mice, ameliorated the histopathological structure of the colon tissue, down-regulated pro-inflammatory cytokines, and up-regulated anti-inflammatory cytokines. The results of 16S rDNA sequences analysis with the Illumina MiSeq platform showed that IN could modulate the balance of gut microbiota, especially by down-regulating the relative quantity of Turicibacter and up-regulating the relative quantity of Peptococcus. The therapeutic effect of IN may be closely related to the anaerobic gram-positive bacteria of Turicibacter and Peptococcus. The inferred metagenomes from 16S data using PICRUSt demonstrated that decreased metabolic genes, such as through biosynthesis of siderophore group nonribosomal peptides, non-homologous end-joining, and glycosphingolipid biosynthesis of lacto and neolacto series, may maintain microbiota homeostasis during inflammation from IN treatment in DSS-induced colitis. [ABSTRACT FROM AUTHOR]

Chronic pain, along with comorbid psychiatric disorders, is a common problem worldwide. A growing number of studies have focused on non-opioid-based medicines, and billions of funds have been put into digging new analgesic mechanisms. Peripheral inflammation is one of the critical causes of chronic pain, and drugs with anti-inflammatory effects usually alleviate pain hypersensitivity. Sophoridine (SRI), one of the most abundant alkaloids in Chinese herbs, has been proved to exert antitumor, antivirus and anti-inflammation effects. Here, we evaluated the analgesic effect of SRI in an inflammatory pain mouse model induced by complete Freund's adjuvant (CFA) injection. SRI treatment significantly decreased pro-inflammatory factors release after LPS stimuli in microglia. Three days of SRI treatment relieved CFA-induced mechanical hypersensitivity and anxiety-like behavior, and recovered abnormal neuroplasticity in the anterior cingulate cortex of mice. Therefore, SRI may be a candidate compound for the treatment of chronic inflammatory pain and may serve as a structural basis for the development of new drugs. Graphical Abstract [ABSTRACT FROM AUTHOR]

Abstract Gracilistones A (1) and B (2), two new eudesmane-type sesquiterpenoids with an unusual tetrahydrofuran-fused 6/6/5 tricyclic ring system, were obtained from Acanthopanax gracilistylus under the guidance of LC-MS investigation. Their structures and absolute configurations were assigned by extensive spectroscopic analyses and quantum calculation methods. Compounds 1 and 2 showed potent inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages, compared with the positive control L-NMMA. In addition, compounds 1 and 2 were also evaluated for their antioxidant (DPPH• and ABTS•+) and xanthine oxidase (XO) inhibitory activities, and they exhibited weak inhibitory effects at 100 μM. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Ligularia przewalskii (Maxim.) Diels ( LP ) (called zhangyetuowu in Chinese), is generally found in moist forest areas in the western regions of China. The root, leaves and flower of LP are utilized as a common traditional medicine in China. It has been utilized conventionally in herbal remedies for the remedy of haemoptysis, asthma, pulmonary phthisis, jaundice hepatitis, food poisoning, bronchitis, cough, fever, wound healing, measles, carbuncle, swelling and phlegm diseases. Aim of the study The review aims to provide a systematic summary of LP and to reveal the correlation between the traditional uses and pharmacological activities in order to provide updated, comprehensive and categorized information and identify the therapeutic potential for its use as a new medicine. Materials and methods The relevant data were searched by using the keywords “ Ligularia przewalskii ” “phytochemistry”, “pharmacology”, “Traditional uses”, and “Toxicity” in “Scopus”, “Scifinder”, “Springer”, “Pubmed”, “Wiley”, “Web of Science”, “China Knowledge Resource Integrated databases (CNKI)”, “Ph.D.” and “M.Sc. dissertations”, and a hand-search was done to acquire peer-reviewed articles and reports about LP . The plant taxonomy was validated by the databases “The Plant List”, “Flora Reipublicae Popularis Sinicae”, “A Collection of Qinghai Economic Plants”, “Inner Mongolia plant medicine Chi”, Zhonghua-bencao and the Standard of Chinese herbal medicine in Gansu. Results Based on the traditional uses, the chemical nature and biological effects of LP have been the focus of research. In modern research, approximately seventy-six secondary metabolites, including thirty-eight terpenoids, nine benzofuran derivatives, seven flavonoids, ten sterols and others, were isolated from this plant. They exhibit anti-inflammatory, antioxidative, anti-bacterial and anti-tumour effects, and so on. Currently, there is no report on the toxicity of LP , but hepatotoxic pyrrolizidine alkaloids (HPA) were first detected with LC/MS n in LP , and they have potential hepatotoxicity. Conclusions The lung-moistening, cough-relieving and phlegm-resolving actions of the root of LP are attributed to the anti-inflammatory properties of flavonoids and terpenoids. The heat-clearing, dampness-removing and gallbladder-normalizing (to cure jaundice) actions of the flowers of LP are based on the anti-inflammatory, antioxidant and hepatoprotective activity properties of terpenoids, flavonoids and sterols. The Traditional Chinese Medicine (TCM) characteristics of LP (bitter flavour) corroborate its potent anti-inflammatory effects. In addition, the remarkable anti-inflammatory and antioxidant capacities of LP contribute to its anti-tumour and antitussive activities. Many conventional uses of LP have now been validated by modernized pharmacological research. For future research, further phytochemical and biological studies need to be conducted on LP, In particular, the safety, mechanism of action and efficacy of LP could be of future research interest before beginning clinical trials. More in vivo experiments and clinical studies are encouraged to further clarify the relation between traditional uses and modern applications. Regarding the roots, leaves and flowers of LP , their chemical compositions and clinical effects should be compared. The information on LP will be helpful in providing and identifying its therapeutic potential and economic value for its use as a new medicine in the future. [ABSTRACT FROM AUTHOR]

• 1,4-Addition Ugi reaction was catalyzed by catalyst derived from Tröger's base and BINOL. • α , β -Keto amide 2-arylformyl-3-(arylamino)cyclopent-2-enecarboxamides were obtained. • The product were gained in high yield under mild condition. • The reaction involving various aromatic amines can go smoothly. • The result showed the high efficiency and universality of the catalyst. The 1,4-addition Ugi reaction can provide complex, novel and bioactive structures. However, Ugi reaction involving the 1,4-addition process has rarely been reported due to the Michael addition of amine to α , β -unsaturated ketones or aldehydes prevents the formation of the key intermediate iminium ion. In this paper, a Schiff base catalyst derived from Tröger's base-NH 2 and (R)-BINOL-CHO was used successfully to promote the four-component 1,4-addition Ugi reaction of α , β -unsaturated cyclic ketones, carboxylic acids, aromatic amines and isocyanides to afford an α , β -keto amide 2-arylformyl-3-(arylamino)cyclopent-2-enecarboxamides in high yield (6 , 83–96%) under mild condition. A variety of aromatic amines participated in the reaction efficiently, which showed the high efficiency of the catalyst. A reasonable catalysis and formation mechanism were come up with. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a notable health problem and may considerably affect the quality of human life. Previously, the protective roles of tryptanthrin (TRYP) against dextran sulfate sodium (DSS) induced colitis has been proved, but the concrete mechanism remained elusive. It has been suggested that TRYP could diminish the weight loss and improve the health conditions of mice with DSS induced colitis. Hematoxylin and eosin staining revealed that TRYP could improve the histopathological structure of the colon tissue. Two signaling pathways (TNF-α/NF-κBp65 and IL-6/STAT3) were investigated using immunochemistry and western blot. The detected concentrations of the two cytokines TNF-α and IL-6 showed that their levels decreased after TRYP treatment of the colitis. The protein expression level of NF-κBp65 in cytoplasm increased after TRYP treatment of the induced colitis. However, the protein level of NF-κBp65 in the nucleus decreased after administration of TRYP. The expression level of IκBα, the inhibitory protein of NF-κBp65, was tested and the results suggested that TRYP could inhibit the degradation of IκBα. The phosphorylation level of STAT3 was inhibited by TRYP and the expression level of STAT3 and p-STAT3 decreased after administration of TRYP. We conclude that TRYP improves the health condition of mice with DSS induced colitis by regulating the TNF-α/NF-κBp65 and IL-6/STAT3 signaling pathways via inhibiting the degradation of IκBα and the phosphorylation of STAT3. [ABSTRACT FROM AUTHOR]