Increased chromosome damage in systemic sclerosis skin fibroblasts.
OBJECTIVE
To evaluate chromosome damage, by means of micronucleus frequency, in dermal fibroblasts from affected and non-affected skin from systemic sclerosis (SSc) patients and from controls.


METHODS
Primary fibroblast cultures were obtained by biopsy from affected and non-affected skin from SSc patients. Control fibroblasts were derived from skin remnants from plastic surgery in healthy adults. The number of micronuclei-bearing cells per 1000 binucleated cells (MN+ cells/1000 BN) was determined in cultures with and without clastogenic stimulus (bleomycin 3 μg/mL).


RESULTS
Primary cultures from 10 SSc patients (affected and non-affected skin) and nine controls were analysed by two blinded examiners. In the absence of bleomycin, the frequency of MN+ cells was higher in cultures from affected (14.01 ± 11.96 MN+ cells/1000 BN; p = 0.004) and non-affected (15.41 ± 13.58 MN cells/1000 BN; p = 0.005) skin from SSc patients as compared to fibroblasts from healthy controls (4.74 ± 3.30 MN cells/1000 BN). In bleomycin-treated cultures, the frequency of MN cells was higher in SSc affected (38.03 ± 26.14 MN cells/1000 BN; p = 0.041) and non-affected skin (38.47 ± 17.88 MN cells/1000 BN; p = 0.034) as compared to healthy control fibroblasts (20.54 ± 13.09 MN cells/1000 BN). There was no difference in the frequency of MN cells in cultures from affected and non-affected skin of SSc patients.


CONCLUSIONS
This is the first demonstration that dermal fibroblasts from SSc patients present an increased frequency of spontaneous and clastogen-induced micronuclei. Increased clastogenesis seems to be a widespread phenomenon in SSc because fibroblasts from clinically affected and non-affected skin presented the equivalent increased micronuclei counts.
Martins
E P
EP
Rheumatology Division, Federal University of São Paulo, Brazil.
Fuzzi
H T
HT
Kayser
C
C
Alarcon
R T
RT
Rocha
M G C
MG
Chauffaille
M L
ML
Andrade
L E C
LE
D000328:Adult; D001706:Biopsy; D001761:Bleomycin / Q000009:adverse effects; D016022:Case-Control Studies; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000473:pathology*; D006801:Humans; D008297:Male; D048629:Micronuclei, Chromosome-Defective / Q000139:chemically induced / Q000706:statistics & numerical data*; D008875:Middle Aged; D009153:Mutagens / Q000009:adverse effects; D018384:Oxidative Stress / Q000235:genetics; D015995:Prevalence; D012595:Scleroderma, Systemic / Q000235:genetics* / Q000473:pathology*; D012867:Skin / Q000473:pathology*
D009153:Mutagens; D001761:Bleomycin