Fluorophilia

Fluorophore-containing compounds adhere non-specifically to injured neurons

Bridget Hawkins, Christopher J. Frederickson, Douglas Dewitt, Donald Prough

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Ionic (free) zinc (Zn 2 +) is implicated in apoptotic neuronal degeneration and death. In our attempt to examine the effects of Zn 2 + in neurodegeneration following brain injury, we serendipitously discovered that injured neurons bind fluorescein moieties, either alone or as part of an indicator dye, in histologic sections. This phenomenon, that we have termed "fluorophilia", is analogous to the ability of degenerating neuronal somata and axons to bind silver ions (argyrophilia - the basis of silver degeneration stains). To provide evidence that fluorophilia occurs in sections of brain tissue, we used a wide variety of indicators such as Fluoro-Jade (FJ), a slightly modified fluorescein sold as a marker for degenerating neurons; Newport Green, a fluorescein-containing Zn 2 + probe; Rhod-5N, a rhodamine-containing Ca 2 + probe; and plain fluorescein. All yielded remarkably similar staining of degenerating neurons in the traumatic brain-injured tissue with the absence of staining in our sham-injured brains. Staining of presumptive injured neurons by these agents was not modified when Zn 2 + in the brain section was removed by prior chelation with EDTA or TPEN, whereas staining by a non-fluorescein containing Zn 2 + probe, N-(6-methoxy-8-quinolyl)-p-toluenesulfonamide (TSQ), was suppressed by prior chelation. Thus, certain fluorophore-containing compounds nonspecifically stain degenerating neuronal tissue in histologic sections and may not reflect the presence of Zn 2 +. This may be of concern to researchers using indicator dyes to detect metals in brain tissue sections. Further experiments may be advised to clarify whether Zn 2 +-binding dyes bind more specifically in intact neurons in culture or organotypic slices.

Original languageEnglish (US)
Pages (from-to)28-35
Number of pages8
JournalBrain Research
Volume1432
DOIs
StatePublished - Jan 13 2012

Fingerprint

Fluorescein
Neurons
Coloring Agents
Staining and Labeling
Brain
Silver
Rhodamines
Carisoprodol
Edetic Acid
Brain Injuries
Axons
Zinc
Metals
Research Personnel
Ions

Keywords

  • Fluorescent indicator
  • Fluoro-Jade
  • Neuronal degeneration
  • Newport Green
  • Traumatic brain injury
  • TSQ

ASJC Scopus subject areas

  • Neuroscience(all)
  • Clinical Neurology
  • Developmental Biology
  • Molecular Biology

Cite this

Fluorophilia : Fluorophore-containing compounds adhere non-specifically to injured neurons. / Hawkins, Bridget; Frederickson, Christopher J.; Dewitt, Douglas; Prough, Donald.

In: Brain Research, Vol. 1432, 13.01.2012, p. 28-35.

Research output: Contribution to journalArticle

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