Extracorporeal shock waves enhance normal fibroblast proliferation in vitro and activate mRNA expression for TGF-beta1 and for collagen types I and III.
OBJECTIVE
Extracorporeal shock waves (ESWs) are used to good effect in the treatment of soft tissue injuries, but the underlying mechanisms are still unknown. We therefore determined the effects of ESWs on normal fibroblasts in vitro, in order to assess treatment-induced cell response.


METHODS
A normal human fibroblast cell line (NHDF-12519) was treated with ESWs generated by a piezoelectric device (Piezoson 100; Richard Wolfe) using different protocols of impulses (300, 1,000, or 2,000 shots) and energy (0.11 or 0.22 mJ/mm(2)). Untreated controls and treated cells were cultivated for 12 days following a single shock-wave treatment. Viability, growth rate, and expression of mRNA for TGFbeta-1 and collagen types I and III were evaluated at days 3, 6, 9, and 12.


RESULTS
1 hour after shock-wave treatment, cell viability showed a decrease related mainly to impulse numbers applied. Fibroblasts treated with energy of 0.22 mJ/mm(2) subsequently showed an increase in proliferation from day 6 to day 9 that was higher than in untreated controls, without interference with the normal cell kinetic profile. mRNA expression was also higher in treated fibroblasts than in untreated controls for TGFbeta-1 on day 6 and day 9, for collagen type I on day 6, and for collagen type III on day 9.


CONCLUSIONS
These in vitro data confirm that the main factors involved in the repair process of connective tissues are activated by ESWs. The study gives the rationale for, and may provide schedules for, ESW treatment of tendonopathies.
Berta
Laura
L
Department of Clinical Pathophysiology, University of Turin, Turin, Italy.
Fazzari
Annamaria
A
Ficco
Anna Maria
AM
Enrica
Patrizia Maurici
PM
Catalano
Maria Graziella
MG
Frairia
Roberto
R
D002460:Cell Line; D049109:Cell Proliferation / Q000528:radiation effects*; D002470:Cell Survival / Q000528:radiation effects; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism*; D024061:Collagen Type III / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000528:radiation effects*; D015870:Gene Expression / Q000528:radiation effects; D019220:High-Energy Shock Waves / Q000627:therapeutic use*; D006801:Humans; D012333:RNA, Messenger / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing / Q000528:radiation effects*
D024042:Collagen Type I; D024061:Collagen Type III; D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1