F. Hernandezhernandez et al., NOCARDIA-BRASILIENSIS - IN-VITRO AND IN-VIVO GROWTH-RESPONSE TO STEROID SEX-HORMONES, Mycopathologia, 132(2), 1995, pp. 79-85
As actinomycetoma is more frequent in males than in females, the possi
bility that hormones might modify the Nocardia brasiliensis growth and
the course of experimental actinomycetoma was explored. Five N. brasi
liensis strains were grown on Sabouraud agar containing estradiol, pro
gesterone or testosterone, in 3 different concentrations. Colony diame
ters were measured weekly for 7 weeks. N. brasiliensis strains were al
so grown in Sabouraud broth containing hormones. Glucose concentration
was measured weekly for 6 weeks. Finally, experimental actinomycetoma
was produced in male and female hormone-treated mice. Invasion rate,
plantar pad diameter and positive retrocultures were assessed. In vitr
o experiments showed that progesterone and testosterone inhibit N. bra
siliensis growth, manifested by lower colony diameters and greater glu
cose concentrations. In vivo experiments demonstrated that estradiol l
imits actinomycetoma development. Progesterone and testosterone induce
d greater diameters of inoculated plantar pads and greater invasion ra
tes with greater positive culture numbers than estradiol. Results part
ially explain the resistance of females to actinomycetoma.