Biomedical subjects

Chen Qing

Publications and source records attributed to Chen Qing.

7 recordsLinked to original sources

PubMed2006

Hypocrellin D, a cytotoxic fungal pigment from fruiting bodies of the ascomycete Shiraia bambusicola.

A fungal pigment, hypocrellin D (1), together with three known perylenequinone derivatives hypocrellin A (2), B (3) and C (4), was isolated from the fruiting bodies of Shiraia bambusicola. Its structure was elucidated on the basis of spectral data including 2D NMR experiments. Hypocrellin D (1) significantly inhibited the growth of tumor cell lines Bel-7721, A-549 and Anip-973 with IC50 values of 1.8, 8.8, 38.4 microg/ml, respectively.

Antibiotics, Antineoplastic↗

PubMed2005

A new cytotoxic lanostane triterpenoid from the basidiomycete Hebeloma versipelle.

A new cytotoxic lanostane triterpenoid, 24(E)-3beta-hydroxylanosta-8,24-dien-26-al-21-oic acid (1), was isolated from the fruiting bodies of the mushroom Hebeloma versipelle. The structure was elucidated on the basis of spectroscopic studies including 2D NMR experiments. Compound 1 moderately inhibited the growth of several tumor cell lines (IC50 10-25.0 microg/ml).

Antibiotics, Antineoplastic↗

PubMed2004

Diterpenoids from Isodon melissoides.

Nine new diterpenoids, melissoidesins M-U (1-9), along with five known analogues, melissoidesin F (10), xindongnin B (11), melissoidesin G (12), melissoidesin E (13), and dawoensin A (14), were isolated from the aerial parts of Isodon melissoides. The structures of new compounds were elucidated by analysis of spectral evidence including extensive 2D NMR data. Compounds 2, 3, 7, 11, 12, and 14 showed cytotoxicity against the human tumor BGC-823 cell line with IC(50) values less than 10 microg/mL, respectively.

Antineoplastic Agents, Phytogenic↗

PubMed2004

Effects of albaconol from the basidiomycete Albatrellus confluens on DNA topoisomerase II-mediated DNA cleavage and relaxation.

The effect of albaconol on the growth of human tumor cell, DNA topoisomerase (topo)-mediated DNA cleavage and direct DNA breakage was investigated. Albaconol inhibited significantly the growth of the human tumor cell lines K562, A549, BGC-823 and Bcap-37, the IC5s values were 7.99 +/- 0.4, 3.17 +/- 0.89, 4.18 +/- 0.14 and 7.45 +/- 2.5 microM, respectively. Albaconol stabilized and increased the topo 11-mediated DNA cleavable complex and inhibited the religation activity of topo II in a dose-dependent manner, but it failed to affect the activity of topo I. Albaconol directly broke pBR322 DNA at high concentrations, but there was no effect on the macromolecule of K562 cells. These results strongly suggest that albaconol targeted specifically to DNA topo II and that this is one of the mechanisms of its antitumor action; the direct action of albaconol on DNA may partly contribute to its anti-tumor activity at high concentrations.

Antineoplastic Agents, Phytogenic↗

PubMed2003

Albaconol from the mushroom Albatrellus confluens induces contraction and desensitization in guinea pig trachea.

The contraction and desensitization induced by albaconol and the influence of capsazepine, capsaicin and extracellular Ca2+ were investigated to see whether the actions were mediated via a specific VR receptor in guinea pig trachea spiral strips in vitro. Both albaconol and capsaicin were contractors of tracheal smooth muscle, but albaconol was not so potent as capsaicin, with -log (M) EC50 values of 4.23 +/- 0.18 (n = 10) and 7.33 +/- 0.21 (n = 10) respectively. 2.5 microM capsazepine competitively antagonized the contractile response to albaconol and capsaicin. Albaconol increased the contraction induced by a low dose of capsaicin (10(-10) to 10(-9) M), but non-competitively antagonized the contraction induced by a high dose of capsaicin (10(-8) to 10(-3) M). Either albaconol (1 or 100 mM) or capsaicin (3 or 10 microM) was able to desensitize the isolated guinea pig bronchi to subsequent addition of albaconol. Capsazepine (5.0 microM) significantly prevented the desensitization induced by either albaconol (1 or 100mM) or capsaicin (3 or 10 microM). Extracellular Ca2+ was essential for albaconol to induce excitation, but it did not affect albaconol- or capsaicin-induced desensitization. In summary, the results from the present study suggest that albaconol induces contraction and desensitization of guinea pig trachea in vitro as a partial agonist for VR.

Agaricales↗

PubMed2003

Actinomycin D inhibiting K562 cell apoptosis elicited by salvicine but not decreasing its cytotoxicity.

AIM: To study the effects of actinomycin D (Act D) on the cytotoxicity and apoptosis elicited by salvicine in human leukemia K562 cells. METHODS: Growth inhibition of K562 cells was measured by the microculture tetrozolium (MTT) assay. Cell apoptosis was evaluated by fluorescence microscopy, DNA agarose gel electrophoresis, and flow cytometry. RESULTS: Following exposure of K-562 cells to salvicine plus Act D for 24 h, Act D at the concentrations of 0.04, 0.4, and 4 micromol/L potentiated the cytotoxicity of salvicine 6.25 micromol/L to some degree. The mean growth inhibitory rates went from 8 % up to 69 %, 71 %, and 70 %, respectively. However, the same enhancement of Act D did not continue to emerge at the higher concentrations than salvicine 6.25 micromol/L. Act D enhanced, or at least, did not decrease the cytotoxicity of salvicine against K562 cells. Fluorescence microscopy, DNA agarose gel electrophoresis, and flow cytometry revealed that Act D concentration-dependently inhibited the induction of apoptosis by salvicine in the same cell line. CONCLUSION: The combination of salvicine and Act D in a proper range of concentrations is able to enhance the cytotoxicity of salvicine against K562 cells though inhibiting apoptosis. The other mechanisms of cell death except apoptosis may be implicated in the process.

Antibiotics, Antineoplastic↗

PubMedDate not supplied

Anticancer activity of tirucallane triterpenoids from Amoora dasyclada.

A new tetranortriterpene 3alpha-acetoxy-24,25,26,27-tetranortirucalla-7-ene-23(21)-lactone (3), and eleven other compounds were isolated from the twigs of Amoora dasyclada. The structure of compound 3 was identified on the basis of spectroscopic data, and the bioactive experiments of 1 and 3-5 against AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) are documented. Among them, compound 5 exhibited a strong activity against SMMC-7721.

Animals↗