CURCUMIN PROTECS OLFACTORY ENSHEATHING CELLS EXPOSED TO HYPOXIA

Curcumin is a natural polyphenolic compound which is extracted from the rhizomes of Curcuma longa and it has been used in traditional Chinese and Indian medicine for centuries. Recently, a wide range of pharmacological activities have been widely recognized, such as anti-inflammatory, anti-tumor, anti-depression and anti-oxidant activity; in addition curcumin is able to cross the blood-brain barrier because of its low molecular weight, therefore it has been used as a therapeutic agent since it confers protection in different neurodegenerative diseases, cerebral ischemia and excitotoxicity. Olfactory Ensheathing Cells (OECs), glial cells of the olfactory system, are able to secrete several neurotrophic growth factors, promoting axonal growth and supporting remyelination of damaged axons. OEC transplantation has emerged as a possible experimental therapy to induce repair of spinal cord injury (SCI), even if the functional recovery is still limited. Since hypoxia is a secondary effect in SCI, this in vitro study investigates on the protective effect of curcumin in OECs exposed to hypoxia. Primary OECs were obtained from neonatal rat olfactory bulbs and placed both in normal and hypoxic conditions. Furthermore, some cells were grown with basic Fibroblast Growth Factor (bFGF) and/or curcumin at different concentration and times. The results were analyzed by immunocytochemical procedures to assess morphological features and by MTT test to evaluate cell viability. We showed that curcumin stimulated cell viability in OECs grown in normal and hypoxic conditions and the synergistic effect of curcumin and bFGF was the most effective exerting protection on OECs. Since SCI is often accompanied by secondary insults, such as ischemia or hypoxia, our results suggest that curcumin in combination with bFGF might be considered a possible approach for restoration in injuries.