Phototoxicity of Vascular Endothelial Cells Caused by Contact with Talaporfin Sodium for 15-120 Min: In Vitro and In Vivo Studies.

Abstract

OBJECTIVE:

To reveal the mechanism of vascular patency in the myocardium after photosensitization immediately after talaporfin sodium (TS) injection in a canine model, we investigated acute injury to vascular endothelial cells (VECs) in vitro and in vivo.

BACKGROUND DATA:

There are many reports of vascular shutdown within the target region in photodynamic therapy with TS. Vascular patency within healthy canine myocardium in which a photosensitization reaction starts immediately after injection of TS has been reported.

MATERIALS AND METHODS:

TS fluorescence in human umbilical vein endothelial cells and cell lethality were measured with drug contact time (DCT) up to 120 min at 20 μg/mL. Dependence of radiant exposure on cell lethality with 60 min DCT was investigated using two albumin concentrations that corresponded to those in plasma and interstices. Irradiation (21 mW/cm) outside the adventitia of canine cervical veins for 167 or 667 sec was emitted through a diffuser probe 30 min after intravenous injection of TS (2.5 mg/kg). Veins were extracted ∼30 min after the reaction and stained with von Willebrand factor.

RESULTS:

Intracellular fluorescence increased, but not cell lethality, with increasing DCT. Cell lethality increased gradually and reached 100% over 20 J/cm2 in the albumin concentration in the interstices. Normal VECs were found at the acute phase over 20 J/cm2 with a TS concentration in plasma of ∼14 μg/mL in vivo.

CONCLUSIONS:

VEC injury after a photosensitization reaction to healthy tissue shortly after TS injection might be low enough for the blood vessels to be patent.

• Authors: Risa Hamada, Emiyu Ogawa, Tsunenori Arai
• Journal: Photomedicine and laser surgery (Photomed Laser Surg) Vol. 35 Issue 6 Pg. 305-310 (Jun 2017) ISSN: 1557-8550 [Electronic] United States
• PMID: 28437192 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Porphyrins
• Talaporfin

Topics

• Animals
• Cell Death (drug effects)
• Cells, Cultured
• Dogs
• Endothelial Cells (drug effects)
• Injections, Intralesional
• Models, Animal
• Myocardium
• Photochemotherapy (methods)
• Photosensitivity Disorders
• Porphyrins (pharmacology, toxicity)
• Sensitivity and Specificity
• Time Factors
• Vascular Patency (drug effects)