Diclofenac inhibits proliferation and differentiation of neural stem cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in clinical situations as anti-inflammatory, analgesic and antipyretic drugs. However, it is still unknown whether NSAIDs have effects on the development of the central nervous system. In the present study, we investigated the effects of NSAIDs on neural stem cell (NSC) proliferation and differentiation into neurons. In contrast to aspirin, naproxen, indomethacin and ibuprofen, treatment with diclofenac (10 μM) for 2 days induced the death of NSCs in a concentration-dependent manner. Diclofenac also inhibited the proliferation of NSCs and their differentiation into neurons. Treatment with diclofenac resulted in nuclear condensation (a morphological change due to apoptosis of NSCs) 24 hr after the treatment and activated caspase-3 after 6 hr, indicating that diclofenac may cause apoptosis of neuronal cells via activation of the caspase cascade. These results suggest that diclofenac may affect the development of the central nervous system.