Linked Life Data

18754047

Source:http://linkedlifedata.com/resource/pubmed/id/18754047

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2008-8-28
pubmed:abstractText
The hexylester of 5-aminolevulinic acid (HAL) is a very efficient precursor of the photosensitizer protoporphyrin IX (PpIX) for photodynamic therapy (PDT). Our previous study, performed in rat orthotopic bladder tumors, indicated an opposite effect of HAL/PpIX-PDT according to HAL concentration. The present study investigated possible reasons for this differential effect considering the impact of extracted amounts of PpIX in normal and tumor bearing bladders along with PpIX distribution in distinctive histopathological layers. High performance liquid chromatography (HPLC) analysis of tumor and normal bladder tissues after 8 mM and 16 mM HAL instillation showed that PpIX was the main porphyrin species. The PpIX production in tumor bladders instilled with 8 mM HAL was significantly higher than after 16 mM HAL. Fluorescence confocal microscopy demonstrated a punctuate bright fluorescence pattern in tumor zones of bladders instilled with 8 mM HAL, whereas a more diffuse cytoplasmatic fluorescence distribution was observed after 16 mM HAL instillation. Immunofluorescence staining together with transmission electron microscopy showed severe mitochondrial damage in tumor zones of bladders treated with 8 mM HAL/PpIX PDT, with intact mitochondria in tumor zones of bladders treated with 16 mM HAL/PpIX PDT. We conclude that the differential response to HAL/PpIX PDT in function of HAL concentrations could be attributed to diminished PpIX synthesis and differential intracellular localisation of PpIX. Mitochondria were shown to be the critical photodamaged sites of HAL/PpIX PDT and as such tissue sensitivity to treatment can be estimated through investigation of intracellular PpIX distribution.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1474-905X
pubmed:author
pubmed:issnType
Print
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1018-24
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Analysis of differential PDT effect in rat bladder tumor models according to concentrations of intravesical hexyl-aminolevulinate.
pubmed:affiliation
Photobiology in Cancerology, Centre Alexis Vautrin, CRAN Nancy University, CNRS, Avenue de Bourgogne 54511, and Department of pathology and cytology, University Hospital Nancy, Vandoeuvre les Nancy Cedex, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't