Apoptotic cell death has been proposed to play a role in the neuronal loss observed following traumatic injury in the CNS and PNS. The present study uses an in vitro tissue culture model to investigate whether free fatty acids (FFAs), at concentrations comparable to those found following traumatic brain injury, trigger cell death. Nerve growth factor (NGF)-differentiated PC12 cells exposed to oleic and arachidonic acids (2 : 1 ratio FFA/BSA) showed normal cell survival. However, when cells were exposed to stearic and palmitic acids, there was a dramatic loss of cell viability after 24 h of treatment. The cell death induced by stearic acid and palmitic acid was apoptotic as assessed by morphological analysis, and activation of caspase-8 and caspase-3-like activities.Western blotting showed that differentiated PC12 cells exposed to stearic and palmitic acids exhibited the signature apoptotic cleavage fragment of poly (ADP-ribose) polymerase (PARP). Interestingly, blockade of caspase activities with the pan-caspase inhibitor z-VAD-fmk failed to prevent the cell death observed induced by palmitic or stearic acid. RT-PCR and RNA blot experiments showed an up-regulation of the Fas receptor and ligand mRNA. These findings are consistent with our hypothesis that FFAs may play a role in the cell death associated with trauma in the CNS and PNS.

Cyclodextrins (CDs) are used to deliver hydrophobic molecules in aqueous environments. Methyl-β-cyclodextrin (MβCD), a member of this family of molecules, has been proposed to be a good carrier to deliver fatty acids to cells in culture. This report focuses on studying the in vitro effects of MβCD on nerve growth factor-differentiated PC12 (NGFDPC12) cells, a tissue culture model to study neuronal survival and differentiation. The main findings are: (1) NGFDPC12 cells have normal viability when exposed to 0.12% MβCD but showed a significant loss in cell viability at higher concentrations; (2) NGFDPC12 cells exposed to 0.25% MβCD exhibit nuclear condensation, blebbing and apoptotic bodies, and whole cell lysates exhibited an increase in caspase-3-like activity and high levels of Bax and Bcl-X L protein expression compared to control. Cultures treated with 0.25% MβCD also showed cleavage of normal 21-kDa Bax protein into a 18-kDa fragment. (3) Experiments using 0.12% MβCD to deliver oleic acid did not affect cell viability, in contrast NGFDPC12 cultures in which 0.25% MβCD concentration is used exhibited similar loss of cell viability as observed with 0.25% MβCD alone. Treating these cultures with caspase-3 inhibitor z-VAD-fmk did not protect the cells from MβCD toxic effects. (4) Immortalized Schwann cells (iSC) exposed to MβCD 0.12% did not show loss of cell viability while 0.25% MβCD triggered a significant toxicity but with a different dose and time course dynamic than NGFDPC12 cells. Thus, NGDPC12 or iSC cell cultures exposed to 0.12% MβCD exhibits normal viability while higher concentrations increase in cell death and apoptosis.

Acupuncture is a frequently used adjuvant treatment for chronic pain conditions. The authors report the case of a patient in whom the delayed migration of embedded acupuncture needles into the lumbar spinal canal caused the formation of a cerebrospinal fluid fistula and spine-related headache. The needles were safely removed surgically and the patient improved clinically.

✓Acupuncture is a frequently used adjuvant treatment for chronic pain conditions. The authors report the case of a patient in whom the delayed migration of embedded acupuncture needles into the lumbar spinal canal caused the formation of a cerebrospinal fluid fistula and spine-related headache. The needles were safely removed surgically and the patient improved clinically.