Linked Life Data

9679450

Source:http://linkedlifedata.com/resource/pubmed/id/9679450

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-8-24
pubmed:abstractText
The fluorescent pH probe carboxy-seminaphtorhodafluor-1 (C-Snarf-1) has been used for laser microspectro-fluorometric assays of intracellular pH in 3T3 mouse fibroblasts treated with hypocrellin A. These results are compared to those previously obtained with the structurally related hydroxylated polycyclic quinone, hypericin (Sureau et al., J. Am. Chem. Soc. 118, 9484-9487, 1996). A mean local intracellular pH drop of 0.6 units has been observed in the presence of 1 microM hypocrellin A after 90 s of exposure to 0.1 microW of laser irradiation at 514.5 nm. The time evolution of the cytoplasm acidification for hypocrellin A-treated cells is faster than that for cells treated by hypericin. Thus, release of protons from an excited state of hypocrellin A appears to be more efficient than that from hypericin. In addition, the pH dependence of the quenching of C-Snarf-1 fluorescence in 3T3 cells under continuous irradiation has been observed. It is shown here that under continuous illumination, a pH decrease is able to induce a modification of the intracellular binding equilibrium of C-Snarf-1 that results in an increase of C-Snarf-1 fluorescence intensity. This latter observation suggests that the protons generated upon the photoexcitation of hypericin or its analogs may be involved in the production of other photoreactive species. Finally, we suggest that, just as for hypericin, this pH drop may be involved in the antiviral and antitumor activity of hypocrellin A.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0031-8655
pubmed:author
pubmed:issnType
Print
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44-50
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Hypocrellin A photosensitization involves an intracellular pH decrease in 3T3 cells.
pubmed:affiliation
L.P.B.C., Université P. et M. Curie, Paris, France.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't