No, we haven’t fallen off the face of the earth… just busy. (well, I can’t speak for Bayle)
Interesting news in the AOP section of Nature Medicine. Looks like a combined therapy of cAMP and schwann cells can aid in spinal cord regeneration. This study shows that inhibition of cyclic AMP signaling is a major problem in axon regeneration. (Definitely some connections here with the MM Poo work on growth cone turning in response to cAMP from a pipette.)
Read on for the abstract….
Here’s the abstract:
cAMP and Schwann cells promote axonal growth and functional recovery after spinal cord injury
Damien D Pearse1, Francisco C Pereira2, Alexander E Marcillo1, Margaret L Bates1, Yerko A Berrocal1, Marie T Filbin3 & Mary Bartlett Bunge
Central neurons regenerate axons if a permissive environment is provided; after spinal cord injury, however, inhibitory molecules are present that make the local environment nonpermissive. A promising new strategy for inducing neurons to overcome inhibitory signals is to activate cAMP signaling. Here we show thatcAMP levels fall in the rostral spinal cord, sensorimotor cortex and brainstem after spinal cord contusion. Inhibition of cAMP hydrolysis by the phosphodiesterase IV inhibitor rolipram prevents this decrease and when combined with Schwann cell grafts promotes significant supraspinal and proprioceptive axon sparing and myelination. Furthermore, combining rolipram with an injection of db-cAMP near the graft not only prevents the drop in cAMP levels but increases them above those in uninjured controls. This further enhances axonal sparing and myelination, promotes growth of serotonergic fibers into and beyond grafts, and significantly improves locomotion. These findings show that cAMP levels are key for protection, growth and myelination of injured CNS axons in vivo and recovery of function.