BONE MINERAL DENSITY AND BIOCHEMICAL VARIABLES OF THE IGF SYSTEM IN SMALL FOR GESTATIONAL AGE CHILDREN

SILVANO LILIANA, PÉREZ ADRIANA, MIRAS MIRTA, MUÑOZ LILIANA, PRETEL ESTEBAN, PICOTTO GABRIELA, MARTIN SILVIA, ELÍAS VANINA, SOBRERO GABRIELA, DE GRANDIS SUSANA, ARMELINI PEDRO, TOLOSA DE TALAMONI NORI

Buenos Aires

Congreso; XXII Reunión Anual de la Asociación Argentina de Osteología y Metabolismo Mineral; 2005

Asociación Argentina de Osteología y Metabolismo Mineral

ABSTRACT Body mass is associated with bone mineral density (BMD), which is determined by genetic and environmental factors. The present work was designed to relate BMD and calcium and phosphorus metabolism biochemical variables in small for gestational age (SGA) children, with vitamin D (VDR) and estrogen receptor (ER) genotypes. Children (n=72) included controls, SGA with postnatal catch-up and without catch-up. Serum calcium and phosphorous, PTH, osteocalcin and beta cross-laps (EQLIA), IGF-I and IGFBP3 (IRMA) and acid labil subunit (ALS) by EIA, were measured. DNA was isolated from blood. VDR genotypes were determined using Bsm-I and Fok-I restriction enzymes, while for ER genotypes, Pvu-II y Xba-I were employed. BMD were analyzed in lumbar spine and femoral neck using DEXA (Norland). SGA children without catch-up have lower femoral neck and lumbar spine BMD than those from SGA children with catch-up or control ones (p< 0.01); they also showed lower levels of serum IGF-I, IGFBP3 and ALS (p< 0.01). VDR and ER polymorphism distribution did not show statistically significant differences between groups. Nevertheless, a better femoral BMD in the control group is correlated with the Ff genotype. In conclusion, SGA children without catch-up have biochemical variables related to the IGF system completely different of those from other groups and lower BMD values at both skeletal sites. A BMD-Fok I association is observed in control children while the same tendency has been shown in SGA children.