Three new alkaloids isolated from the stem tuber of Pinellia pedatisecta / 中国天然药物

The present study was designed to determine the chemical constituents of the stem tuber of Pinellia pedatisecta. The chemical constituents were isolated and purified by various chromatographic techniques, and their structures were elucidated on the basis of physicochemical properties and spectral data. Three new alkaloids (compounds 1, 2, and 3) were obtained and identified as 9-((5-methoxypyridin-2-yl)methyl)-9H-purin-6-amine (1), 4-(2-(2, 5-dioxopyrrolidin-1-yl)ethyl)phenyl acetate (2), and N-(9-((5-methoxypyridin-2-yl)methyl)-9H-purin-6-yl)acetamide (3). These compounds were evaluated for their cytotoxicity against human cervical cancer HeLa cells. Compounds 1 and 3 significantly inhibited the proliferation of HeLa cells with IC values being 3.02 ± 0.54 and 7.16 ± 0.62 μmol·L, respectively.

Three new alkaloids isolated from the stem tuber of Pinellia pedatisecta / 中国天然药物

The present study was designed to determine the chemical constituents of the stem tuber of Pinellia pedatisecta. The chemical constituents were isolated and purified by various chromatographic techniques, and their structures were elucidated on the basis of physicochemical properties and spectral data. Three new alkaloids (compounds 1, 2, and 3) were obtained and identified as 9-((5-methoxypyridin-2-yl)methyl)-9H-purin-6-amine (1), 4-(2-(2, 5-dioxopyrrolidin-1-yl)ethyl)phenyl acetate (2), and N-(9-((5-methoxypyridin-2-yl)methyl)-9H-purin-6-yl)acetamide (3). These compounds were evaluated for their cytotoxicity against human cervical cancer HeLa cells. Compounds 1 and 3 significantly inhibited the proliferation of HeLa cells with IC values being 3.02 ± 0.54 and 7.16 ± 0.62 μmol·L, respectively.

Chemical constituents of Spatholobus suberectus / 中国天然药物

AIM@#To investigate chemical constituents of Spatholobus suberectus Dunn.@*METHODS@#Isolation and purification were carried out by column chromatographic methods. Compounds were characterized based on their physical characteristics and spectra data.@*RESULTS@#Seventeen compounds were isolated from ethanol extract of S. suberectus. The structures were elucidated as prestegane B (1), (2R, 3R)-buteaspermanol (2), (+)-medioresinol (3), (2R, 3R)-3,7-dihydroxyflavanone (4), benzeneethanol (5), 4, 7, 2'-trihydroxy-4'-methoxyisoflavanol (6), naringenin (7), blumenol A (8), protocatechuic acid ethyl ester (9), liquiritigenin (10), 7, 4'-dihydroxy-8-methoxy-isoflavone (11), 3, 5, 7, 3', 5'-pentahydroxyflavanone (12), protocatechuic acid (13), glycyroside (14), 8-methylretusin-7-O-β-D-glucopyranoside (15), 3, 3', 4', 5, 6, 7, 8-heptahydroxyflavan (16), and dulcisflavan (17).@*CONCLUSION@#All compounds are firstly isolated from the title plant and compounds 1, 3 were isolated from the Spatholobus genus for the first time.

Inhibition of epithelial-mesenchymal transition in A549 cell by transfected Napsin A / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Epithelial-mesenchymal transition is a cellular process characterized by the loss of cell adhesion, inhibition of E-cadherin expression, and increased cell mobility. Cells without Napsin A are susceptible to transition. Further studies are required to investigate whether this transition can be reversed by restoration of Napsin A.</p><p><b>METHODS</b>A Napsin A expression vector PLJM1-Napsin A plasmid was constructed and then transfected into the epithelial cell line A549 by lentivirus transfection to obtain A549-PLJM1-Napsin A cell line. Cell proliferation was assayed by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide and cell cycle was measured by flow cytometry. The E-cadherin, type I collagen, and focal adhesion kinase mRNA level was detected by reverse transcription-polymerase chain reaction. The Napsin A, E-cadherin, type I collagen, and focal adhesion kinase protein level in A549 cells was detected by Western blotting.</p><p><b>RESULTS</b>Transforming growth factor-b1 induced epithelial-mesenchymal transition in A549 cells, as demonstrated by significant reduction of E-cadherin mRNA and protein levels (P < 0.01) as well as up-regulation of type I collagen (P < 0.01). Transfection of Napsin A in A549 cells can partially block the transforming growth factor-b1-regulated expression of E-cadherin and type I collagen (P < 0.01). In addition, transforming growth factor-b1-induced cell proliferation was inhibited by Napsin A (P < 0.01). Further study demonstrated that Napsin A caused G(0)/G(1) arrest and inhibited the expression of focal adhesion kinase (P < 0.01), a key protein in the integrin signaling pathway, in the in vitro epithelial-mesenchymal transition model.</p><p><b>CONCLUSIONS</b>Sustained Napsin A expression in A549 cells can inhibit the transforming growth factor-b1-induced epithelial-mesenchymal transition. This may be due to the Napsin A-mediated inhibition of focal adhesion kinase expression and integrin signaling pathway.</p>

Study on free radical mechanism of guanxin II in antagonizing ischemic myocardial damage / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study comparatively the effect of Guanxin II and its constituents, including Salvia, Red Peony root, Chuanxiong, Safflower and Dalbergia wood, in scavenging active oxygen free radical (OFR) to explore their mechanism in overcoming the experimental acute ischemic myocardial injury and protecting myocardial tissue.</p><p><b>METHODS</b>The experimental acute myocardial ischemic model was established by intraperitoneal injection of pituitrin to rats. OFR level in animal heart tissue was directly measured with low-temperature electron paramagnetic resonance (EPR) spectrometer.</p><p><b>RESULTS</b>The pathological examination of HE stained slide of myocardial tissue and electrocardiography of model animal showed that typical changes of acute myocardial ischemia occurred in myocardial tissue, EPR showed that OFR level in myocardial tissue increased abnormally. The ethanol extract of Guanxin II and its constituents could lower the increased OFR level close to normal, thus to alleviate the myocardial damage.</p><p><b>CONCLUSION</b>Overproduction of OFR could induce damage of heart tissue, its level could be measured directly using low temperature EPR. One of the molecular mechanisms of Guanxin II and its constituents in antagonizing and repairing myocardial damage is to scavenge the abnormal increased active OFR in tissue. This study has provided a basis for further studying the mechanism of Chinese composite recipes and their constituents.</p>