TGF-beta1 TESTICULAR EXPRESSION IN TRANSGENIC MICE OVER-EXPRESSING hCG. IN VITRO EFFECT OF hCG AND PROGESTERONE IN FVB/N MICE TESTES

CANDELA R. GONZALEZ; BETINA GONZALEZ; SUSANA RULLI; ILPO HUHTANIEMI; RICARDO CALANDRA; SILVIA GONZALEZ-CALVAR

Buenos Aires, Argentina

Congreso; VIII Jornadas Multidisciplinarias de la Sociedad Argentina de Biología; 2006

Sociedad Argentina de Biología

TGF-b1 TESTICULAR EXPRESSION IN TRANSGENIC MICE OVER-EXPRESSING hCG. IN VITRO EFFECT OF hCG AND PROGESTERONE IN FVB/N MICE TESTES. Gonzalez C1, Gonzalez B1, Rulli S1, Huhtniemi I2, Calandra R1,3, Gonzalez Calvar SI1,4 1IBYME, CONICET, Argentina, 2 University of Turku, Finland, 3IMBICE, Argentina, 4 School of Medicine, UBA, Argentina. E-mail: cgonzalez@dna.uba.ar Transgenic male mice (TG) over-expressing a and b subunits of hCG are infertile and show enhanced steroidogenesis with high levels of testosterone and progesterone. The chronic hCG hyper-stimulation leads to Leydig cell hyperplasia and hypertrophy in prepubertal mice, being reduced at adulthood (Rulli et al; Endocrinology, 144: 4980, 2003). Transforming growth factor-b1 (TGF-b1) is a growth factor that regulates cell cycle progression, cell differentiation, reproductive function and development. The aim of this study was to analyze by RT-PCR the expression of TGF-b1 and endoglin (a co-receptor which leads to proliferation) in the testes of TG at 3 and 8 weeks of age, as well as the “in vitro” effect of hCG and progesterone on TGF-b1 testicular expression in wild type mice (FVB/n) at both ages. TG showed an increase in the expression of TGF-b1 at 8 weeks of age (p<0.05). Endoglin showed an increment on its expression at 3 weeks of age (p<0.05). “In vitro” incubation (1 hour) with hCG (10UI/ml) induced the expression of TGF-b1 at both ages studied (p<0.05). Otherwise, “in vitro” incubation (1 hour) with progesterone (10-5 M) had no effect on TGF-b1 expression. These results indicate that high and chronic levels of hCG induced TGF-b1 testicular expression in TG at 8 weeks of age. In contrast, this factor is not regulated by progesterone, at least in these experimental conditions. The expression of endoglin in TG correlates with the hyperplasia and hypertrophy of Leydig cells in prepubertal animals. The temporal expression of TGF-b1 might influence the growth and development of the testes in this experimental model.