Linked Life Data

19692249

Source:http://linkedlifedata.com/resource/pubmed/id/19692249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2009-9-2
pubmed:abstractText
Mitochondria are attractive targets in photodynamic therapy. Two conjugates: TPP-Rh (a porphyrin-rhodamine B conjugate) and TPP-AO (a porphyrin-acridine orange conjugate), each possessing a single delocalized lipophilic cation, were designed and synthesized as photosensitizers. Their ability to target the mitochondria for photodynamic therapy was evaluated. The conjugates were synthesized by conjugating a monohydroxy porphyrin (TPP-OH) to rhodamine B (Rh B) and acridine orange base (AO), respectively, via a saturated hydrocarbon linker. To evaluate the efficiency of the conjugates as photosensitizers, their photophysical properties and in vitro photodynamic activities were studied in comparison to those of TPP-OH. Although fluorescence energy transfer (FRET) was observed in the conjugates, they were capable of generating singlet oxygen at rates comparable to TPP-OH. Biologically, exciting results were observed with TPP-Rh, which showed a much higher phototoxicity [IC(50), 3.95 microM: irradiation of 400-850 nm light (3 mW cm(-2)) for 1 h] than either TPP-OH or Rh B (both, IC(50), >20 microM) without significant dark toxicity at 20 microM. This improved photodynamic activity might be due to a greater cellular uptake and preferential localization in mitochondria. The cellular uptake of TPP-Rh was 8 and 14 times greater than TPP-OH and Rh B, respectively. In addition, fluorescence imaging studies suggest that TPP-Rh localized more in mitochondria than TPP-OH. On the other hand, TPP-AO showed some dark toxicity at 10 microM and stained both mitochondria and nucleus. Our study suggests that conjugation of photosensitizers to Rh might provide two benefits, higher cellular uptake and mitochondrial localization, which are two important subjects in photodynamic therapy.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1464-3391
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6631-40
pubmed:dateRevised
2010-4-27
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Evaluation of delocalized lipophilic cationic dyes as delivery vehicles for photosensitizers to mitochondria.
pubmed:affiliation
Department of Chemistry and Biochemistry, South Dakota State University, Brookings, SD 57007, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't