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Leonurus japonicus Houtt., also known as motherwort, is a traditional Chinese medicine that was first identified in Shennong Bencao Jing , the first and essential pharmacy monograph in China. L. japonicus has been regarded as a good gynecological medicine since ancient times. It has been widely used in clinical settings for treatment of gynecological diseases and postnatal rehabilitation with good efficacy and low adverse effects. The main purpose of this study was to determine the angiogenic and wound healing effects of total alkaloid fraction from L. japonicus Houtt. (TALH) in vivo and in vitro. In addition, the main bioactive components of total alkaloids were to be identified and analyzed in this study. First, the UHPLC/Q-TOF-MS method was used to identify and quantify the major components in the TALH extract. The wound healing activity was evaluated in vivo using a rat full-thickness cutaneous wound model. Histological study of wound healing in rat model was performed via immunohistochemistry and immunofluorescence. Cell proliferation was determined by MTT assay. Wound healing and transwell assays were used for detection of cell migration. The effect on tube formation was determined by tube formation assay in HUVECs. Western blot and RT-PCR were used to detect the expressions of relative proteins and genes respectively. Knock-down of SRC by siRNA was done to verify the crucial role of SRC in promotion of angiogenesis induced by TALH. Seven characteristic peaks were recognized in the UHPLC/Q-TOF-MS spectrum, while four of the main components were quantified. The wound model in rats showed that treatment of TALH promoted wound healing by stimulating cellular proliferation and collagen deposition. In vitro experiments showed that co-treatment of TALH and VEGF increased cell proliferation, migration and tube formation in HUVECs. Mechanistic studies suggested that the co-treatment increased gene expressions of SRC, MEK1/2 and ERK1/2, as well as the phosphorylation levels of these proteins. Furthermore, the effect of co-treatment was attenuated after SRC knockdown, suggesting that SRC plays an important role in angiogenesis and wound healing induced by TALH and VEGF co-treatment. Our results showed that TALH was one of the main active components of L. japonicus that promoted angiogenesis and wound healing by regulating the SRC/MEK/ERK pathway. Our study provided scientific basis for better clinical application of L. japonicas. [Display omitted] [ABSTRACT FROM AUTHOR]

A palladium-catalyzed regiodivergent C1 insertion multicomponent reaction involving aryne, CO, and 2-iodoaniline is established to construct the scaffolds of phenanthridinone and acridone alkaloids. Regioselective control is achieved under the guidance of selective ligands. The phenanthridinones are solely obtained under ligand-free condition. In comparison, application of the electron-abundant bidentate ligand dppm afforded the acridones with high efficiency. The release rate of the aryne from the precursor assists the regioselectivity of insertion as well, which was revealed through interval NMR tracking. A plausible mechanism was suggested based on the control experiments. Representative natural products and two types of natural product analogues were synthesized divergently through this tunable method. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed regiodivergent C1 insertion multicomponent reaction involving aryne, CO, and 2-iodoaniline is established to construct the scaffolds of phenanthridinone and acridone alkaloids. Regioselective control is achieved under the guidance of selective ligands. The phenanthridinones are solely obtained under ligand-free condition. In comparison, application of the electron-abundant bidentate ligand dppm afforded the acridones with high efficiency. The release rate of the aryne from the precursor assists the regioselectivity of insertion as well, which was revealed through interval NMR tracking. A plausible mechanism was suggested based on the control experiments. Representative natural products and two types of natural product analogues were synthesized divergently through this tunable method. [ABSTRACT FROM AUTHOR]

Abstract: A statistic approach using response surface methodology (RSM) for optimization of the ultra-high performance liquid chromatography (UHPLC) gradient and ionization response of electrospray ionization mass spectrometry (ESI-MS) to analyze the main alkaloids from the plant matrices of six Meconopsi species is presented. The optimization was performed with Box–Behnken designs (BBD) and the multicriteria response variables were described using global Derringer''s desirability. Four parameters of UHPLC and six major parameters of ESI-MS were investigated for their contribution to analytes separation and response, leading to a total of 27 and 54 experiments being performed for each instrument, respectively. Quantitative analysis of four main alkaloids in nine samples from six Meconopsis species was employed to evaluate the statistical significance of the parameters on UHPLC–QTOF/ESI-MS analytes response. The results indicated that the optimized UHPLC–QTOF-MS method is very sensitive with the limit of detections (LODs) ranging from 0.5 to 0.1ng/ml. The overall intra-day and the inter-day variations were less than 2.45%. The recovery of the method was in the range of 94.3–104.8% with RSD less than 4.0%. This approach has important implication in sensitivity enhancement of the ultra-trace determination of alkaloids from complex matrixes in the fields of natural products, metabolomics and pharmacokinetics. [Copyright &y& Elsevier]

Herpesviruses establish long-term latent infection for the life of the host and are known to cause numerous diseases. The prevalence of viral infection is significantly increased and causes a worldwide challenge in terms of health issues due to drug resistance. Prolonged treatment with conventional antiviral drugs is more likely to develop drug-resistant strains due to mutations of thymidine nucleoside kinase or DNA polymerase. Hence, the development of alternative treatments is clearly required. Natural products and their derivatives have played a significant role in treating herpesvirus infection rather than nucleoside analogs in drug-resistant strains with minimal undesirable effects and different mechanisms of action. Numerous plants, animals, fungi, and bacteria-derived compounds have been proved to be efficient and safe for treating human herpesvirus infection. This review covers the natural antiherpetic agents with the chemical structural class of alkaloids, flavonoids, terpenoids, polyphenols, anthraquinones, anthracyclines, and miscellaneous compounds, and their antiviral mechanisms have been summarized. This review would be helpful to get a better grasp of anti-herpesvirus activity of natural products and their derivatives, and to evaluate the feasibility of natural compounds as an alternative therapy against herpesvirus infections in humans. [ABSTRACT FROM AUTHOR]

Abstract: The root tubers of Stemona tuberosa, Stemona japonica and Stemona sessilifolia are recognized by the Pharmacopoeia of the People''s Republic of China as authentic sources of the herb Radix Stemonae (Baibu). Careful anatomical analyses of these three species, whose identities were confirmed by flowering and fruiting samples, revealed that the root tubers of Stemona tuberosa could be distinguished from those of the other two species by the presence of scattered fibers in the cortex and pith and by the absence of thickened striations on the surface of velamen cells. HPLC analyses demonstrated that the total alkaloid profiles could be grouped into four types represented as the major component by stenine-type Stemona alkaloids such as tuberostemonine (4) and neotuberostemonine (3), or by non-stenine types such as croomine (1) and stemoninine (2). Nevertheless, all these samples demonstrated different degrees of antitussive properties in guinea pigs. These results suggested that non-stenine-type of Stemona alkaloids also contributed to the antitussive properties. The variations in chemical profiles among herb samples add difficulty in ensuring quality control in botanical products. [Copyright &y& Elsevier]

Abstract: An alkaloid named 6α-hydroxycroomine (1) as well as the known croomine (2), both belonging to the tuberostemospironine-alkaloid type, were isolated from Stemona tuberosa as the major components. The structure of 1 was elucidated through extensive spectroscopic analyses. Comparison of the HPLC profiles of the total alkaloids and the crude methanol extract showed that both compounds are naturally occurring. The first isolation of 1 and 2 from S. tuberosa has chemotaxonomic significance, confirming the close relationship between Stemona and Croomia. The trnL sequences of plants from the four genera of Stemonaceae cluster together as a clade, further lending support to retaining them in a single family. [Copyright &y& Elsevier]

Abstract: By optimizing the extraction, separation and analytical conditions, a reliable and accurate high-performance liquid chromatography (HPLC) method coupled with photodiode array detector (DAD) was developed for simultaneous quantitative determination of six Aconitum alkaloids, i.e., aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine, in Chinese medicinal herbs, aconite roots, and 12 proprietary Chinese medicines containing processed aconite roots. The separation of these Aconitum alkaloids was achieved on an ODS column with gradient elution using solvents of acetonitrile and ammonium bicarbonate buffer (pH 10.0±0.2). Intra-assay and inter-assay precision of the analytes were less than 2.97%, and the average recovery rates obtained were in the range of 90–103% for all with RSDs below 3.28%. Good linear relationships were showed with correlation coefficients for the analytes exceeded 0.999. Quantitative analysis of the six Aconitum alkaloids in the unprocessed and processed aconite roots and in twelve proprietary Chinese medicines containing processed aconite roots showed that the contents of the alkaloids varied significantly. This method and quantitation results can provide a scientific and technical platform to the products manufacturers for setting up a quality control standard as well as to the public for quality and safety assurance of the proprietary Chinese medicines and other herbal preparations containing aconite roots. [Copyright &y& Elsevier]

The Pd-catalyzed reactions of in situ generated arynes with o-iodoanilines in the presence of carbon monoxide are described. [ABSTRACT FROM AUTHOR]