Immune Suppression and Neuronal Toxicity

Immune suppressants are required for differentiated cells derived from embryonic stem cells and for bone marrow transplants to prevent severe graft versus host reactions. Immune suppressants often include corticosteroids (cortisone) that in elevated concentrations are toxic to neural progenitor cells and new neurons. Therefore the use of these immune suppressants could be counterproductive in stem cell therapies for neurological disorders, particularly those involving learning and memory. Umbilical cord stem cells can be beneficial in treating neurological injuries and disorders if the stem cells are well tested for purity and potency so that immune suppressants are not needed.

• Corticosterone enhances neural toxicity in the hippocampus.

• Chronic corticosterone impairs inhibitory avoidance learning

• Corticosterone reduces mitochondrial membrane potential in hippocampal neurons

• Glucocorticoids can cause hippocampal cell death by apoptosis and necrosis