Abstract
In the monocrotaline (MCT) rat model of pulmonary hypertension, the pulmonary vascular endothelium is thought to be the early target of the bifunctionally reactive metabolite monocrotaline pyrrole (MCTP). In previous studies, bovine pulmonary arterial endothelial cells (BPAEC) exposed to MCTP exhibited inhibition of proliferation. Since other compounds that crosslink DNA lead to cell cycle alterations, we utilized BPAEC to correlate the effects of MCTP on the cell cycle with the extent of covalent binding of [14C]MCTP to BPAEC DNA. Dose response (0.0 to 50.0 μg MCTP/ ml) and 96-hr time course (5 μg MCTP/ml low dose or 34.5 μg MCTP/ml high dose) studies were carried out followed by flow cytometric cell cycle analysis. High concentrations of MCTP caused cell cycle arrest in S phase, beginning by 24 hr, while an S phase delay was observed at low concentrations, but progressed to a G2 + M phase arrest by 48 hr. Covalent DNA binding (34.5 μg/ml of [14C]MCTP incubated with BPAEC) occurred within 1 hr and progressively increased through 96 hr. In conclusion, covalent binding of MCTP to DNA is associated with cell cycle arrest; however, the position of cell cycle arrest is dependent on dose, with an S phase arrest at high concentrations and a G2 + M phase arrest at low concentrations of MCTP. The mechanism by which MCTP induces proliferative inhibition could be cell cycle arrest.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 319-329 |
| Number of pages | 11 |
| Journal | Toxicology and Applied Pharmacology |
| Volume | 141 |
| Issue number | 1 |
| DOIs | |
| State | Published - Nov 1996 |
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ASJC Scopus subject areas
- Pharmacology
- Toxicology
Cite this
Cell cycle alterations associated with covalent binding of monocrotaline pyrrole to pulmonary artery endothelial cell DNA. / Thomas, H. C.; Lamé, M. W.; Wilson, Dennis W; Segall, H. J.
In: Toxicology and Applied Pharmacology, Vol. 141, No. 1, 11.1996, p. 319-329.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Cell cycle alterations associated with covalent binding of monocrotaline pyrrole to pulmonary artery endothelial cell DNA
AU - Thomas, H. C.
AU - Lamé, M. W.
AU - Wilson, Dennis W
AU - Segall, H. J.
PY - 1996/11
Y1 - 1996/11
N2 - In the monocrotaline (MCT) rat model of pulmonary hypertension, the pulmonary vascular endothelium is thought to be the early target of the bifunctionally reactive metabolite monocrotaline pyrrole (MCTP). In previous studies, bovine pulmonary arterial endothelial cells (BPAEC) exposed to MCTP exhibited inhibition of proliferation. Since other compounds that crosslink DNA lead to cell cycle alterations, we utilized BPAEC to correlate the effects of MCTP on the cell cycle with the extent of covalent binding of [14C]MCTP to BPAEC DNA. Dose response (0.0 to 50.0 μg MCTP/ ml) and 96-hr time course (5 μg MCTP/ml low dose or 34.5 μg MCTP/ml high dose) studies were carried out followed by flow cytometric cell cycle analysis. High concentrations of MCTP caused cell cycle arrest in S phase, beginning by 24 hr, while an S phase delay was observed at low concentrations, but progressed to a G2 + M phase arrest by 48 hr. Covalent DNA binding (34.5 μg/ml of [14C]MCTP incubated with BPAEC) occurred within 1 hr and progressively increased through 96 hr. In conclusion, covalent binding of MCTP to DNA is associated with cell cycle arrest; however, the position of cell cycle arrest is dependent on dose, with an S phase arrest at high concentrations and a G2 + M phase arrest at low concentrations of MCTP. The mechanism by which MCTP induces proliferative inhibition could be cell cycle arrest.
AB - In the monocrotaline (MCT) rat model of pulmonary hypertension, the pulmonary vascular endothelium is thought to be the early target of the bifunctionally reactive metabolite monocrotaline pyrrole (MCTP). In previous studies, bovine pulmonary arterial endothelial cells (BPAEC) exposed to MCTP exhibited inhibition of proliferation. Since other compounds that crosslink DNA lead to cell cycle alterations, we utilized BPAEC to correlate the effects of MCTP on the cell cycle with the extent of covalent binding of [14C]MCTP to BPAEC DNA. Dose response (0.0 to 50.0 μg MCTP/ ml) and 96-hr time course (5 μg MCTP/ml low dose or 34.5 μg MCTP/ml high dose) studies were carried out followed by flow cytometric cell cycle analysis. High concentrations of MCTP caused cell cycle arrest in S phase, beginning by 24 hr, while an S phase delay was observed at low concentrations, but progressed to a G2 + M phase arrest by 48 hr. Covalent DNA binding (34.5 μg/ml of [14C]MCTP incubated with BPAEC) occurred within 1 hr and progressively increased through 96 hr. In conclusion, covalent binding of MCTP to DNA is associated with cell cycle arrest; however, the position of cell cycle arrest is dependent on dose, with an S phase arrest at high concentrations and a G2 + M phase arrest at low concentrations of MCTP. The mechanism by which MCTP induces proliferative inhibition could be cell cycle arrest.
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U2 - 10.1006/taap.1996.0289
DO - 10.1006/taap.1996.0289
M3 - Article
VL - 141
SP - 319
EP - 329
JO - Toxicology and Applied Pharmacology
JF - Toxicology and Applied Pharmacology
SN - 0041-008X
IS - 1
ER -