Kinetics of Photobleaching of Protoporphyrin IX in the Skin of Nude Mice Exposed to Different Fluence Rates of Red Light

Nuclear magnetic line widths data have been used to determine the rate of solvent exchange between the coordination sphere of Fe(III)-protoporphyrin(IX)dimethylester or Fe(III)-tetraphenylporphyrin and the bulk phase of 1-methylimidazol/chloroform. At temperatures below 322 K both porphyrins are in the low-spin state and separate PMR absorption caused by the methyl protons of two 1-methylimidazol molecules complexed in fifth and sixth position of ferri-porphyrins is detected. At T ≳ 320 K an accelerated exchange of these ligands was observed and the underlying kinetic parameters have been extracted. It was found that this exchange takes place when the paramagnetic species is in its low-spin state. For 240 K ≲ T ≲ 290 K dynamic line broadening of bulk phase 1-methylimidazol indicates occurrence of chemical exchange attributed to 1-methylimidazol interacting with ferri-porphyrin in addition to the strongly bound axial ligands.

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Topical Administration of Tetrasodium-Mesotetraphenyl-Porphinesulfonate (TPPS): Correlation between Drug Penetration and Depth of Necrosis in Skin of Nude Mice following Red Light Irradiation

Tumori Journal ◽

10.1177/030089168707300102 ◽

1987 ◽

Vol 73 (1) ◽

pp. 11-17 ◽

Cited By ~ 2

Author(s):

Renato Marchesini ◽

Elsa Melloni ◽

Giovanni Bottiroli ◽

Salvatore Andreola ◽

Giannino Fava ◽

...

Keyword(s):

Photodynamic Therapy ◽

Nude Mice ◽

Red Light ◽

Local Treatment ◽

Topical Administration ◽

Skin Lesions ◽

Drug Penetration ◽

Suitable Treatment ◽

Epithelial Layers ◽

Photosensitizing Agent

The main side effect in photodynamic therapy is photosensitization of the patient's skin following systemic administration of the photosensitizing agent. In the case of superficial lesions, this problem can be avoided by topically applying the drug: in this way a local treatment can be performed. We tested the photosensitizing properties of a 2 % solution of TPPS (tetrasodium-tetraphenylporphinesulfonate) in a vehicle containing a penetration enhancer, Azone, on skin of nude mice. An aliquot of 0.1 ml/cm2 of the solution was painted on the skin overlying an s.c. implanted NMU-1 tumor. Subsequently, animals were sacrificed at different times after application. Fluorescence microscopy revealed that TPPS penetration depth was related to time elapsed after application and to painting modalities. Solution penetration was enhanced by wiping with ether immediately before painting. Irradiation at 80 mW/cm2 for 20 min with a dye laser emitting at 640 am, 4 h after TPPS application, produced necrosis of the upper skin layers, up to 0.2 mm in depth. These findings suggest that topical TPPS administration, followed by laser irradiation, may be a suitable treatment modality for skin lesions involving epithelial layers, even though several aspects of this metodology need further investigation.

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Influence of Light Exposure on the Kinetics of Protoporphyrin IX Formation in Normal Skin of Hairless Mice After Application of 5-Aminolevulinic Acid Methyl Ester

Journal of Investigative Dermatology ◽

10.1111/j.0022-202x.2005.23863.x ◽

2005 ◽

Vol 125 (5) ◽

pp. 1039-1044 ◽

Cited By ~ 10

Author(s):

Johan Moan ◽

LiWei Ma ◽

Vladimir Iani ◽

Asta Juzeniene

Keyword(s):

Methyl Ester ◽

Aminolevulinic Acid ◽

Light Exposure ◽

Normal Skin ◽

Protoporphyrin Ix ◽

Acid Methyl Ester ◽

Hairless Mice ◽

Acid Methyl ◽

Kinetics Of

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Response of Liverwort Cells to Peroxidizing Herbicides

Zeitschrift für Naturforschung C ◽

10.1515/znc-1992-0613 ◽

1992 ◽

Vol 47 (5-6) ◽

pp. 394-399

Author(s):

Shuji Iwata ◽

Naoko Nakayama ◽

Shunji Nakagawara ◽

Yoshimoto Ohta ◽

Takaharu Tanaka ◽

...

Keyword(s):

Cell Growth ◽

Oxidative Damage ◽

Early Treatment ◽

Protoporphyrin Ix ◽

Cell Suspension Cultures ◽

Exponential Phase ◽

Marchantia Polymorpha ◽

Late Exponential Phase ◽

Kinetics Of

Cell suspension cultures of the liverwort, Marchantia polymorpha L. were found useful to study the influence of peroxidizing herbicides either on the greening process or on the fully green cells. The cells of both physiological stages exhibit a characteristic sensitivity to the herbicides. The sensitivity increased rapidly during the exponential phase of growth, reached a maximum during the late exponential phase, and then decreased in the stationary phase. We investigated the kinetics of accumulation of protoporphyrin IX (PPIX) in Marchantia cells treated with several peroxidizing herbicides at various stages of cell growth, and observed a correlation between accumulation of PPIX and herbicidal damage. The glutathione (GSH) content in the cell was also investigated to examine the role of GSH against herbicide treatment. In the light, GSH levels in the cells treated with AFM rose rapidly reaching a peak after 8 h, and rapidly decreased subsequently. The beginning of PPIX accumulation coincided with the decline of GSH after 8 h of treatment. Obviously, GSH plays a key role in protection against oxidative damage caused by AFM in the early treatment period. In the dark, AFM also induced an accumulation of GSH and PPIX, followed by a decline in GSH and PPIX contents during a 20 h incubation. The decline of PPIX was observed several hours after GSH starts to decrease, remaining at a constant level for the following 40 h, leading to accumulation of an other fluorescent still-unknown pigment.

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