Free axial vibrations at 0 to 200 Hz positively affect extracellular matrix messenger ribonucleic acid expression in bovine nucleus pulposi.
METHODS
Bovine caudal intervertebral discs (IVDs) were exposed to free axial vibration for 10 to 60 minutes at 0 to 0.5 g and 0 to 200 Hz. Expression of messenger ribonucleic acid for aggrecan, collagen type I, collagen type II, biglycan, decorin, and versican were assayed, as was apoptosis.


OBJECTIVE
To determine the vibration conditions which are most effective in altering intervertebral disc IVD gene expression.


BACKGROUND
Various studies have suggested widely varying effects of vibration in the IVD, ranging from harmful (increased risk of degeneration) to beneficial (increased analgesia) to neutral (no effect).


METHODS
Vibration was applied using a custom designed voice coil system, which generated controlled motion in the axial direction. Gene expression in the nucleus pulposus was assessed using RT-PCR and the SYBR green chemistry; apoptosis was assessed using TUNEL staining.


RESULTS
Expression of messenger ribonucleic acids for biglycan, collagen type I, collagen type II, decorin, and versican were significantly affected by vibration duration, frequency, and amplitude. Aggrecan was unaffected. Of the 3 factors, amplitude had the largest and widest effect.


CONCLUSIONS
Expression of extracellular matrix genes was significantly upregulated at high amplitudes (>0.4 g) in as little as 10 minutes. This may indicate a potential therapeutic stimulus; periodic application of controlled vibration could positively influence matrix maintenance. Further studies on the protein level and long-term effects are warranted.
Desmoulin
Geoffrey T
GT
Optima Health Solutions International Corporation (KKT International), Vancouver, British Columbia, Canada.
Reno
Carol R
CR
Hunter
Christopher J
CJ
D053674:Aggrecans / Q000235:genetics; D000818:Animals; D017209:Apoptosis; D058578:Biglycan; D002417:Cattle; D024042:Collagen Type I / Q000235:genetics; D024043:Collagen Type II / Q000235:genetics; D058575:Decorin; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D020869:Gene Expression Profiling; D020287:In Situ Nick-End Labeling; D066298:In Vitro Techniques; D007403:Intervertebral Disc / Q000166:cytology / Q000378:metabolism*; D011509:Proteoglycans / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053675:Versicans / Q000235:genetics; D014732:Vibration
D053674:Aggrecans; D058578:Biglycan; D024042:Collagen Type I; D024043:Collagen Type II; D058575:Decorin; D016326:Extracellular Matrix Proteins; D011509:Proteoglycans; D012333:RNA, Messenger; D053675:Versicans