Related Experiment Videos
Acid-labile subunit (ALS) measurements in children
A Nimura1, N Katsumata, R Horikawa
1Department of Endocrinology and Metabolism, National Children's Medical Research Center, Tokyo, Japan.
Insights
Serum acid-labile subunit (ALS) levels increase with age in children, peaking earlier in girls. Low ALS may indicate growth hormone deficiency (GHD) in children, aiding diagnosis.
Area of Science:
- Pediatric Endocrinology
- Growth Hormone Axis
- Biochemical Markers
Background:
- Insulin-like growth factors (IGFs) circulate in a ternary complex with IGFBP-3 and acid-labile subunit (ALS).
- Previous research suggests serum ALS levels exhibit age- and sex-dependent variations.
Purpose of the Study:
- To investigate serum ALS levels in normal children and those with growth hormone deficiency (GHD).
- To determine the relationship between ALS, IGF-I, and IGFBP-3 levels.
- To evaluate the diagnostic utility of ALS in childhood GHD.
Main Methods:
- Serum ALS levels were measured in 264 healthy children (5 days to 16 years) and 15 children with GHD.
- Age and sex were recorded for all participants.
- Correlations between ALS, IGF-I, and IGFBP-3 were analyzed.
Main Results:
- Serum ALS levels increased with age, peaking in mid-to-late puberty, approximately 2 years earlier in girls than boys.
- ALS levels showed significant positive correlations with IGF-I and IGFBP-3 levels.
- 6 of 7 children with complete GHD (CGHD) had ALS levels below -2SD; 1 of 8 with partial GHD (PGHD) did.
Conclusions:
- Serum ALS levels are regulated by growth hormone (GH) in children.
- Measurement of serum ALS is a valuable tool for diagnosing complete GHD in pediatric patients.
Abstract:
Almost all of the serum IGFs are found in a ternary complex composed of IGF, IGFBP-3 and acid-labile subunit (ALS). It was reported that ALS levels were age- and sex-dependent. In the present study we measured serum ALS levels in 264 normal children (145 boys and 119 girls) aged from 5 days to 16 years, and 15 patients with growth hormone deficiency (GHD) aged from 11 months to 13 years. Serum ALS levels increased during childhood, and reached peak values in mid to late puberty. ALS levels reached their highest levels 2 years earlier in girls than in boys. Serum ALS levels were significantly correlated with serum IGF-I levels and IGFBP-3 levels. Serum ALS levels were below -2SD in 6 out of 7 children with complete GHD (CGHD), while serum ALS levels were below -2SD in 1 out of 8 patients with partial GHD (PGHD). These results indicate that serum ALS levels are regulated by GH, and that the measurement of ALS is useful for the diagnosis of CGHD in children.