Related Experiment Video
Updated: Jun 18, 2026
Chemogenetic Regulation in Reprogrammed Stem Cell-derived Precursor Cells in Treating Neurodegenerative Diseases
Published on: May 2, 2025
Delta opioid peptide DADLE and naltrexone cause cell cycle arrest and differentiation in a CNS neural progenitor cell
Shang-Yi Tsai1, Chung-Ting Lee, Teruo Hayashi
1Cellular Pathobiology Section, Cellular Neurobiology Research Branch, Intramural Research Program, NIDA, NIH, DHHS, Baltimore, Maryland 21224, USA.
Abstract:
Opioids have been demonstrated to play an important role in CNS development by affecting proliferation and differentiation in various types of neural cells. This study examined the effect of a stable delta opioid peptide [D-Ala(2), D-Leu(5)]-enkephalin (DADLE) on proliferation and differentiation in an AF5 CNS neural progenitor cell line derived from rat mesencephalic cells. DADLE (1 pM, 0.1 nM, or 10 nM) caused a significant growth inhibition on AF5 cells. The opioid antagonist naltrexone at 0.1 nM also caused growth inhibition in the same cells. When DADLE and naltrexone were both added to the AF5 cells, the resultant growth inhibition was apparently additive. DADLE alone or DADLE in combination with naltrexone did not cause apoptosis as evidenced by negative TUNEL staining. The cell-cycle progression analysis indicated that both DADLE (0.1 nM) and naltrexone (0.1 nM) caused an arrest of AF5 cell cycle progression at the G1 checkpoint. Neuronal marker indicated that DADLE- or naltrexone-treated AF5 cells tend to differentiate more when compared to controls. Results demonstrate the nonopioid action of both DADLE and naltrexone on cell cycle arrest and differentiation in a CNS neural progenitor cell line. Results also suggest some potential utilization of DADLE and/or naltrexone in stem cell research.
Insights
This study found that [D-Ala(2), D-Leu(5)]-enkephalin (DADLE) and naltrexone inhibit neural progenitor cell growth and promote differentiation, suggesting non-opioid roles in CNS development and potential stem cell applications.
Area of Science:
- Neuroscience
- Developmental Biology
- Pharmacology
Background:
- Opioids influence central nervous system (CNS) development by modulating neural cell proliferation and differentiation.
- Understanding these effects is crucial for developmental neuroscience and regenerative medicine.
Purpose of the Study:
- To investigate the impact of a stable delta opioid peptide, [D-Ala(2), D-Leu(5)]-enkephalin (DADLE), on the proliferation and differentiation of AF5 CNS neural progenitor cells.
- To examine the effects of the opioid antagonist naltrexone on these cells.
Main Methods:
- AF5 neural progenitor cells were treated with varying concentrations of DADLE (1 pM, 0.1 nM, 10 nM) and naltrexone (0.1 nM).
- Cell proliferation was assessed, and apoptosis was evaluated using TUNEL staining.
- Cell cycle progression was analyzed, and differentiation markers were examined.
Main Results:
- DADLE and naltrexone significantly inhibited AF5 cell growth.
- Both compounds induced cell cycle arrest at the G1 checkpoint without causing apoptosis.
- DADLE and naltrexone treatment promoted neuronal differentiation in AF5 cells.
Conclusions:
- DADLE and naltrexone exhibit non-opioid actions on CNS neural progenitor cells, affecting cell cycle arrest and differentiation.
- These findings suggest potential therapeutic applications for DADLE and naltrexone in stem cell research and CNS development.
