[HTML][HTML] Intra-arterial drug and light delivery for photodynamic therapy using Visudyne®: Implication for atherosclerotic plaque treatment

M Jain, M Zellweger, A Frobert, J Valentin… - Frontiers in …, 2016 - frontiersin.org
M Jain, M Zellweger, A Frobert, J Valentin, H Bergh, G Wagnières, S Cook, MN Giraud
Frontiers in physiology, 2016frontiersin.org
Photodynamic therapy (PDT), which is based on the activation of photosensitizers with light,
can be used to reduce plaque burden. We hypothesized that intra-arterial photosensitizer
administration and photo-activation will lead to high and rapid accumulation within the
plaque with reduced systemic adverse effects. Thus, this “intra-arterial” PDT would be
expected to have less side effects and due to the short time involved would be compatible
with percutaneous coronary interventions. Aim: We characterized the dose-dependent …
Photodynamic therapy (PDT), which is based on the activation of photosensitizers with light, can be used to reduce plaque burden. We hypothesized that intra-arterial photosensitizer administration and photo-activation will lead to high and rapid accumulation within the plaque with reduced systemic adverse effects. Thus, this “intra-arterial” PDT would be expected to have less side effects and due to the short time involved would be compatible with percutaneous coronary interventions.
Aim: We characterized the dose-dependent uptake and efficacy of intra-arterial PDT using Liposomal Verteporfin (Visudyne®), efficient for cancer-PDT but not tested before for PDT of atherosclerosis.
Methods and Results: Visudyne® (100, 200, and 500 ng/ml) was perfused for 5–30 min in atherosclerotic aorta isolated from ApoE−/− mice. The fluorescence Intensity (FI) after 15 min of Visudyne® perfusion increased with doses of 100 (FI-5.5 ± 1.8), 200 (FI-31.9 ± 1.9) or 500 ng/ml (FI-42.9 ± 1.2). Visudyne® (500 ng/ml) uptake also increased with the administration time from 5 min (FI-9.8 ± 2.5) to 10 min (FI-23.3 ± 3.0) and 15 min (FI-42.9 ± 3.4) before reaching saturation at 30 min (FI-39.3 ± 2.4) contact. Intra-arterial PDT (Fluence: 100 and 200 J/cm2, irradiance-334 mW/cm2) was applied immediately after Visudyne® perfusion (500 ng/ml for 15 min) using a cylindrical light diffuser coupled to a diode laser (690 nm). PDT led to an increase of ROS (Dihydroethidium; FI-6.9 ± 1.8, 25.3 ± 5.5, 43.4 ± 13.9) and apoptotic cells (TUNEL; 2.5 ± 1.6, 41.3 ± 15.3, 58.9 ± 6%), mainly plaque macrophages (immunostaining; 0.3 ± 0.2, 37.6 ± 6.4, 45.3 ± 5.4%) respectively without laser irradiation, or at 100 and 200 J/cm2. Limited apoptosis was observed in the medial wall (0.5 ± 0.2, 8.5 ± 4.7, 15.3 ± 12.7%). Finally, Visudyne®-PDT was found to be associated with reduced vessel functionality (Myogram).
Conclusion: We demonstrated that sufficient accumulation of Visudyne® within plaque could be achieved in short-time and therefore validated the feasibility of local intravascular administration of photosensitizer. Intra-arterial Visudyne®-PDT preferentially affected plaque macrophages and may therefore alter the dynamic progression of plaque development.
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