8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle

Keith L. March, Brian L. Patton, Robert L. Wilensky, David R. Hathaway

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Background. Smooth muscle cell proliferation plays a major role in the genesis of restenosis after angioplasty or vascular injury. Although the effects of arterial exposure to high-energy radiation sources such as laser have been investigated in detail, the effects on vascular cells of low-intensity radiant energy in combination with photoactive agents have not been extensively characterized. Psoralens are photoactive agents that are known to be well tolerated when used in conjunction with local exposure to ultraviolet light in the A band (UVA) for the treatment of various dermatologic proliferative disorders. Methods and Results. We have investigated the effects of psoralen/UVA (PUVA) exposure on the proliferation of bovine aortic smooth muscle cells. Proliferation and viability were assessed over a 14-day period by trypan blue exclusion counts. Cell cycle effects were evaluated by thymidine incorporation and flow cytometry with DNA quantitation after addition of serum or platelet-derived growth factor B-chain (PDGF-BB) to subconfluent cells synchronized by serum withdrawal. No effect was observed after exposure to 8-methoxypsoralen (8-MOP) at concentrations up to 10 μM or UVA irradiation at energies up to 2.5 J/cm2. Longwave ultraviolet light and 8-MOP were found to behave synergistically as potent inhibitors of DNA synthesis in bovine aortic smooth muscle cells with the EC50 in combination ranging from 7 μM at 0.35 J/cm2 to 0.2 μM at 2.1 J/cm2. Similar antiproliferative effects were obtained by an inverse variation of dose and energy delivered. After serum stimulation, inhibition of DNA synthesis was found with either an immediate or delayed (16-hour) application of PUVA. This effect was independent of subsequent 8-MOP washout. Flow cytometry of cells treated with PUVA at several times after serum stimulation demonstrated for each time point a block in further cell cycle progression for cells in all phases of the cell cycle. Evaluation of [125I]-labeled PDGF and epidermal growth factor (EGF) binding revealed no effect of PUVA on the apparent number or affinity of PDGF binding sites present but did reveal a dose-dependent inhibition by PUVA of EGF binding. This inhibition of EGF binding occurred increasingly at higher PUVA doses than the cell cycle inhibition and accordingly did not appear to represent a critical mechanism for the antiproliferative effect. Cell counting after a single exposure to PUVA (1 μM, 1.5 J/cm2) revealed complete stasis of cell proliferation over a 28-day period without recurrent exposure. No increase in trypan-positive cells was noted over this period. Conclusions. PUVA treatment represents a novel method for locally inhibiting proliferation of vascular smooth muscle cells without producing cytolysis.

Original languageEnglish
Pages (from-to)184-191
Number of pages8
JournalCirculation
Volume87
Issue number1
StatePublished - Jan 1993

Fingerprint

Methoxsalen
Ficusin
Vascular Smooth Muscle
Smooth Muscle Myocytes
Cell Cycle
Epidermal Growth Factor
Ultraviolet Rays
Serum
Flow Cytometry
Cell Proliferation
Proto-Oncogene Proteins c-sis
Nucleic Acid Synthesis Inhibitors
Trypan Blue
Vascular System Injuries
DNA
Angioplasty
Thymidine
Blood Vessels
Lasers
Binding Sites

Keywords

  • Cytostasis
  • Photoactivation
  • Proliferation
  • Restenosis

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Cite this

March, K. L., Patton, B. L., Wilensky, R. L., & Hathaway, D. R. (1993). 8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle. Circulation, 87(1), 184-191.

8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle. / March, Keith L.; Patton, Brian L.; Wilensky, Robert L.; Hathaway, David R.

In: Circulation, Vol. 87, No. 1, 01.1993, p. 184-191.

Research output: Contribution to journalArticle

March, KL, Patton, BL, Wilensky, RL & Hathaway, DR 1993, '8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle', Circulation, vol. 87, no. 1, pp. 184-191.
March, Keith L. ; Patton, Brian L. ; Wilensky, Robert L. ; Hathaway, David R. / 8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle. In: Circulation. 1993 ; Vol. 87, No. 1. pp. 184-191.
@article{1e5a9837aab14200840139e13c9a8ca7,
title = "8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle",
abstract = "Background. Smooth muscle cell proliferation plays a major role in the genesis of restenosis after angioplasty or vascular injury. Although the effects of arterial exposure to high-energy radiation sources such as laser have been investigated in detail, the effects on vascular cells of low-intensity radiant energy in combination with photoactive agents have not been extensively characterized. Psoralens are photoactive agents that are known to be well tolerated when used in conjunction with local exposure to ultraviolet light in the A band (UVA) for the treatment of various dermatologic proliferative disorders. Methods and Results. We have investigated the effects of psoralen/UVA (PUVA) exposure on the proliferation of bovine aortic smooth muscle cells. Proliferation and viability were assessed over a 14-day period by trypan blue exclusion counts. Cell cycle effects were evaluated by thymidine incorporation and flow cytometry with DNA quantitation after addition of serum or platelet-derived growth factor B-chain (PDGF-BB) to subconfluent cells synchronized by serum withdrawal. No effect was observed after exposure to 8-methoxypsoralen (8-MOP) at concentrations up to 10 μM or UVA irradiation at energies up to 2.5 J/cm2. Longwave ultraviolet light and 8-MOP were found to behave synergistically as potent inhibitors of DNA synthesis in bovine aortic smooth muscle cells with the EC50 in combination ranging from 7 μM at 0.35 J/cm2 to 0.2 μM at 2.1 J/cm2. Similar antiproliferative effects were obtained by an inverse variation of dose and energy delivered. After serum stimulation, inhibition of DNA synthesis was found with either an immediate or delayed (16-hour) application of PUVA. This effect was independent of subsequent 8-MOP washout. Flow cytometry of cells treated with PUVA at several times after serum stimulation demonstrated for each time point a block in further cell cycle progression for cells in all phases of the cell cycle. Evaluation of [125I]-labeled PDGF and epidermal growth factor (EGF) binding revealed no effect of PUVA on the apparent number or affinity of PDGF binding sites present but did reveal a dose-dependent inhibition by PUVA of EGF binding. This inhibition of EGF binding occurred increasingly at higher PUVA doses than the cell cycle inhibition and accordingly did not appear to represent a critical mechanism for the antiproliferative effect. Cell counting after a single exposure to PUVA (1 μM, 1.5 J/cm2) revealed complete stasis of cell proliferation over a 28-day period without recurrent exposure. No increase in trypan-positive cells was noted over this period. Conclusions. PUVA treatment represents a novel method for locally inhibiting proliferation of vascular smooth muscle cells without producing cytolysis.",
keywords = "Cytostasis, Photoactivation, Proliferation, Restenosis",
author = "March, {Keith L.} and Patton, {Brian L.} and Wilensky, {Robert L.} and Hathaway, {David R.}",
year = "1993",
month = "1",
language = "English",
volume = "87",
pages = "184--191",
journal = "Circulation",
issn = "0009-7322",
publisher = "Lippincott Williams and Wilkins",
number = "1",

}

TY - JOUR

T1 - 8-methoxypsoralen and longwave ultraviolet irradiation are a novel antiproliferative combination for vascular smooth muscle

AU - March, Keith L.

AU - Patton, Brian L.

AU - Wilensky, Robert L.

AU - Hathaway, David R.

PY - 1993/1

Y1 - 1993/1

N2 - Background. Smooth muscle cell proliferation plays a major role in the genesis of restenosis after angioplasty or vascular injury. Although the effects of arterial exposure to high-energy radiation sources such as laser have been investigated in detail, the effects on vascular cells of low-intensity radiant energy in combination with photoactive agents have not been extensively characterized. Psoralens are photoactive agents that are known to be well tolerated when used in conjunction with local exposure to ultraviolet light in the A band (UVA) for the treatment of various dermatologic proliferative disorders. Methods and Results. We have investigated the effects of psoralen/UVA (PUVA) exposure on the proliferation of bovine aortic smooth muscle cells. Proliferation and viability were assessed over a 14-day period by trypan blue exclusion counts. Cell cycle effects were evaluated by thymidine incorporation and flow cytometry with DNA quantitation after addition of serum or platelet-derived growth factor B-chain (PDGF-BB) to subconfluent cells synchronized by serum withdrawal. No effect was observed after exposure to 8-methoxypsoralen (8-MOP) at concentrations up to 10 μM or UVA irradiation at energies up to 2.5 J/cm2. Longwave ultraviolet light and 8-MOP were found to behave synergistically as potent inhibitors of DNA synthesis in bovine aortic smooth muscle cells with the EC50 in combination ranging from 7 μM at 0.35 J/cm2 to 0.2 μM at 2.1 J/cm2. Similar antiproliferative effects were obtained by an inverse variation of dose and energy delivered. After serum stimulation, inhibition of DNA synthesis was found with either an immediate or delayed (16-hour) application of PUVA. This effect was independent of subsequent 8-MOP washout. Flow cytometry of cells treated with PUVA at several times after serum stimulation demonstrated for each time point a block in further cell cycle progression for cells in all phases of the cell cycle. Evaluation of [125I]-labeled PDGF and epidermal growth factor (EGF) binding revealed no effect of PUVA on the apparent number or affinity of PDGF binding sites present but did reveal a dose-dependent inhibition by PUVA of EGF binding. This inhibition of EGF binding occurred increasingly at higher PUVA doses than the cell cycle inhibition and accordingly did not appear to represent a critical mechanism for the antiproliferative effect. Cell counting after a single exposure to PUVA (1 μM, 1.5 J/cm2) revealed complete stasis of cell proliferation over a 28-day period without recurrent exposure. No increase in trypan-positive cells was noted over this period. Conclusions. PUVA treatment represents a novel method for locally inhibiting proliferation of vascular smooth muscle cells without producing cytolysis.

AB - Background. Smooth muscle cell proliferation plays a major role in the genesis of restenosis after angioplasty or vascular injury. Although the effects of arterial exposure to high-energy radiation sources such as laser have been investigated in detail, the effects on vascular cells of low-intensity radiant energy in combination with photoactive agents have not been extensively characterized. Psoralens are photoactive agents that are known to be well tolerated when used in conjunction with local exposure to ultraviolet light in the A band (UVA) for the treatment of various dermatologic proliferative disorders. Methods and Results. We have investigated the effects of psoralen/UVA (PUVA) exposure on the proliferation of bovine aortic smooth muscle cells. Proliferation and viability were assessed over a 14-day period by trypan blue exclusion counts. Cell cycle effects were evaluated by thymidine incorporation and flow cytometry with DNA quantitation after addition of serum or platelet-derived growth factor B-chain (PDGF-BB) to subconfluent cells synchronized by serum withdrawal. No effect was observed after exposure to 8-methoxypsoralen (8-MOP) at concentrations up to 10 μM or UVA irradiation at energies up to 2.5 J/cm2. Longwave ultraviolet light and 8-MOP were found to behave synergistically as potent inhibitors of DNA synthesis in bovine aortic smooth muscle cells with the EC50 in combination ranging from 7 μM at 0.35 J/cm2 to 0.2 μM at 2.1 J/cm2. Similar antiproliferative effects were obtained by an inverse variation of dose and energy delivered. After serum stimulation, inhibition of DNA synthesis was found with either an immediate or delayed (16-hour) application of PUVA. This effect was independent of subsequent 8-MOP washout. Flow cytometry of cells treated with PUVA at several times after serum stimulation demonstrated for each time point a block in further cell cycle progression for cells in all phases of the cell cycle. Evaluation of [125I]-labeled PDGF and epidermal growth factor (EGF) binding revealed no effect of PUVA on the apparent number or affinity of PDGF binding sites present but did reveal a dose-dependent inhibition by PUVA of EGF binding. This inhibition of EGF binding occurred increasingly at higher PUVA doses than the cell cycle inhibition and accordingly did not appear to represent a critical mechanism for the antiproliferative effect. Cell counting after a single exposure to PUVA (1 μM, 1.5 J/cm2) revealed complete stasis of cell proliferation over a 28-day period without recurrent exposure. No increase in trypan-positive cells was noted over this period. Conclusions. PUVA treatment represents a novel method for locally inhibiting proliferation of vascular smooth muscle cells without producing cytolysis.

KW - Cytostasis

KW - Photoactivation

KW - Proliferation

KW - Restenosis

UR - http://www.scopus.com/inward/record.url?scp=0027398328&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027398328&partnerID=8YFLogxK

M3 - Article

C2 - 8419006

AN - SCOPUS:0027398328

VL - 87

SP - 184

EP - 191

JO - Circulation

JF - Circulation

SN - 0009-7322

IS - 1

ER -