Estrogen provision by reactive glia decreases apoptosis in the zebra finch (Taeniopygia guttata) - PubMed (original) (raw)

Comparative Study

. 2005 Aug;64(2):192-201.

doi: 10.1002/neu.20147.

Affiliations

• PMID: 15818556
• DOI: 10.1002/neu.20147

Comparative Study

Estrogen provision by reactive glia decreases apoptosis in the zebra finch (Taeniopygia guttata)

Colin J Saldanha et al. J Neurobiol. 2005 Aug.

Abstract

Upregulation of aromatase (estrogen synthase) in glia around the site of neural injury may limit neural degeneration. Systemic administration of estrogen limits neural damage, but the specific role of local estrogen provision in this effect is unclear. In male zebra finches, we tested the effect of local aromatase inhibition and estrogen replacement on type of cellular degeneration and the distance of this degeneration from the source of insult. Subjects received injections of the aromatase inhibitor fadrozole into one telencephalic lobe and fadrozole and estradiol into the contralateral lobe. Seventy-two hours later, we used Fluoro-Jade B and TUNEL to label dying and apoptotic cells, respectively. Since each subject was its own control, we were able to assess the influence of local estrogen replacement in relative distinction from circulating steroids and constitutive aromatization. Cellular degeneration around the lesion was measured with Fluoro-Jade B, TUNEL, and indirectly with aromatase expression. Additionally, the glial nature of aromatase-positive cells around the injury was queried by co-localization with vimentin. The estrogen replaced injury had fewer apoptotic cells clustered more closely around the injury compared to the hemisphere injected with fadrozole alone. Since Fluoro-Jade B and TUNEL labeled similar numbers of cells, and the distance of these cells from the injection was identical, we suggest that estrogen replacement functions primarily to restrict apoptosis in the current paradigm. Lastly, aromatase-positive cells around injuries co-localize vimentin, establishing their glial nature. Thus, glial estrogen provision at sites of neural insult may be critical in limiting the cellular degeneration caused by injury via an inhibition of apoptosis.

PubMed Disclaimer

Similar articles

• Inhibition of injury-induced glial aromatase reveals a wave of secondary degeneration in the songbird brain.
  Wynne RD, Walters BJ, Bailey DJ, Saldanha CJ. Wynne RD, et al. Glia. 2008 Jan 1;56(1):97-105. doi: 10.1002/glia.20594. Glia. 2008. PMID: 17955551
• Glial aromatization decreases neural injury in the zebra finch (Taeniopygia guttata): influence on apoptosis.
  Wynne RD, Saldanha CJ. Wynne RD, et al. J Neuroendocrinol. 2004 Aug;16(8):676-83. doi: 10.1111/j.1365-2826.2004.01217.x. J Neuroendocrinol. 2004. PMID: 15271060
• Aromatase expression and cell proliferation following injury of the adult zebra finch hippocampus.
  Peterson RS, Fernando G, Day L, Allen TA, Chapleau JD, Menjivar J, Schlinger BA, Lee DW. Peterson RS, et al. Dev Neurobiol. 2007 Dec;67(14):1867-78. doi: 10.1002/dneu.20548. Dev Neurobiol. 2007. PMID: 17823932
• Glia-neuron crosstalk in the neuroprotective mechanisms of sex steroid hormones.
  Garcia-Ovejero D, Azcoitia I, Doncarlos LL, Melcangi RC, Garcia-Segura LM. Garcia-Ovejero D, et al. Brain Res Brain Res Rev. 2005 Apr;48(2):273-86. doi: 10.1016/j.brainresrev.2004.12.018. Epub 2005 Jan 15. Brain Res Brain Res Rev. 2005. PMID: 15850667 Review.
• Aromatase enzyme and Alzheimer's disease.
  Hiltunen M, Iivonen S, Soininen H. Hiltunen M, et al. Minerva Endocrinol. 2006 Mar;31(1):61-73. Minerva Endocrinol. 2006. PMID: 16498364 Review.

Cited by

• Neuroprotective astroglial response to neural damage and its relevance to affective disorders.
  Miguel-Hidalgo JJ. Miguel-Hidalgo JJ. Explor Neuroprotective Ther. 2023;3(5):328-345. doi: 10.37349/ent.2023.00054. Epub 2023 Oct 31. Explor Neuroprotective Ther. 2023. PMID: 37920189 Free PMC article.
• Brain-Derived Estrogen and Neurological Disorders.
  Brann DW, Lu Y, Wang J, Sareddy GR, Pratap UP, Zhang Q, Tekmal RR, Vadlamudi RK. Brann DW, et al. Biology (Basel). 2022 Nov 24;11(12):1698. doi: 10.3390/biology11121698. Biology (Basel). 2022. PMID: 36552208 Free PMC article. Review.
• Spatial and temporal specificity of neuroestradiol provision in the songbird.
  Saldanha CJ. Saldanha CJ. J Neuroendocrinol. 2023 Feb;35(2):e13192. doi: 10.1111/jne.13192. Epub 2022 Aug 19. J Neuroendocrinol. 2023. PMID: 35983989 Free PMC article. Review.
• Glial estradiol synthesis after brain injury.
  Saldanha CJ. Saldanha CJ. Curr Opin Endocr Metab Res. 2021 Dec;21:100298. doi: 10.1016/j.coemr.2021.100298. Epub 2021 Nov 27. Curr Opin Endocr Metab Res. 2021. PMID: 35274063 Free PMC article.
• Estrogen as a Neuroprotectant in Both Sexes: Stories From the Bird Brain.
  Saldanha CJ. Saldanha CJ. Front Neurol. 2020 Jun 23;11:497. doi: 10.3389/fneur.2020.00497. eCollection 2020. Front Neurol. 2020. PMID: 32655477 Free PMC article. Review.

Publication types

MeSH terms

Substances

LinkOut - more resources

• Full Text Sources

  • Wiley