Research articleThe role of morphine on rat neural stem cells viability, neuro-angiogenesis and neuro-steroidgenesis properties

- Morphine induced cell cytotoxicity, apoptosis and necrosis in rat neural stem cells.
- Naloxone could blunt the adverse effects of morphine on rat neural stem cells.
- Up-regulation of p53, aromatase and 5-alpha reductase genes occurred in morphine-primed cells while naloxone inhibited these effects.
- Morphine inhibited endothelial differentiation of rat neural stem cells.

A lack of comprehensive data exists on the effect of morphine on neural stem cell neuro-steroidogenesis and neuro-angiogenesis properties. We, herein, investigated the effects of morphine (100 μM), naloxone (100 μM) and their combination on rat neural stem cells viability, clonogenicity and Ki-67 expression over a period of 72 h. Any alterations in the total fatty acids profile under treatment protocols were elucidated by direct transesterification method. We also monitored the expression of p53, aromatase and 5-alpha reductase by real-time PCR assay. To examine angiogenic capacity, in vitro tubulogenesis and the level of VE-cadherin transcript were investigated during neural to endothelial differentiation under the experimental procedure.Cells supplemented with morphine displayed reduced survival (p < 0.01) and clonogenicity (p < 0.001). Flow cytometric analysis showed a decrease in Ki-67 during 72 h. Naloxone potentially blunted morphine-induced all effects. The normal levels of fatty acids, including saturated and unsaturated were altered by naloxone and morphine supplements. Following 48 h, the up-regulation of p53, aromatase and 5-alpha reductase genes occurred in morphine-primed cells. Using three-dimensional culture models of angiogenesis and real time PCR assay, we showed morphine impaired the tubulogenesis properties of neural stem cells (p < 0.001) by the inhibition of trans-differentiation into vascular cells and led to decrease of in VE-cadherin expression. Collectively, morphine strongly impaired the healthy status of neural stem cells by inducing p53 and concurrent elevation of aromatase and 5-alpha reductase activities especially during early 48 h. Also, neural stem cells-being exposed to morphine lost their potency to elicit angiogenesis.