Allopregnanolone attenuates N-methyl-D-aspartate-induced excitotoxicity and apoptosis in the human NT2 cell line in culture.
Progesterone modulates gamma-aminobutyric acid and excitatory amino acid neurotransmitter systems and has neuroprotective properties in models of hypoxia-ischemia. This study examined the in vitro effects of allopregnanolone, the active progesterone metabolite, in models of N-methyl-D-aspartate (NMDA)-induced necrosis and apoptosis. Cultured NT2 neurons were exposed to 1 mM NMDA. Lactate dehydrogenase (LDH) release was measured 24 h later. NMDA at a concentration of 1 mM produced a 39 +/- 19% release of total LDH. Exposure to 10 microM allopregnanolone prior to NMDA exposure reduced LDH release by 51% (P = 0.0028). NMDA stimulated apoptotic cell changes defined by terminal dUTP nick-end labeling (TUNEL) and 5,5', 6,6'-tetrachloro-1,1,3,3'-tetra ethlybenzimidazolycarbocyanide iodide staining were reduced to baseline values by both 10 microM allopregnanolone and 100 microM MK-801. Pretreatment with allopregnanolone (0-10 microM) reduced the percentage of TUNEL-positive cells in a dose-dependent manner (EC(50) = 2.7 +/- 0.1 nM). Physiologic concentrations of allopregnanolone provided protection against both necrotic and apoptotic injury induced by NMDA excitotoxicity.
Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA. ellen.lockhart@mcmail.vanderbilt.edu
Ellen M
EM
Lockhart
David S
DS
Warner
Robert D
RD
Pearlstein
Donald H
DH
Penning
Saeed
S
Mehrabani
Rose-Mary
RM
Boustany
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001238:Asphyxia Neonatorum / Q000378:metabolism* / Q000503:physiopathology; D001562:Benzimidazoles; D002232:Carbocyanines; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D020287:In Situ Nick-End Labeling; D007231:Infant, Newborn; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018696:Neuroprotective Agents / Q000378:metabolism / Q000627:therapeutic use*; D009498:Neurotoxins / Q000494:pharmacology; D011247:Pregnancy; D011280:Pregnanolone / Q000494:pharmacology / Q000627:therapeutic use; D011374:Progesterone / Q000378:metabolism / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured
D001562:Benzimidazoles; D002232:Carbocyanines; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D005456:Fluorescent Dyes; D018696:Neuroprotective Agents; D009498:Neurotoxins; C068624:5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine; D011374:Progesterone; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D011280:Pregnanolone; D007770:L-Lactate Dehydrogenase