Changes in growth hormone receptor gene expression during therapy in children with juvenile idiopathic arthritis.
BACKGROUND
High levels of cytokines in juvenile idiopathic arthritis (JIA) can alter target cell sensitivity to growth hormone (GH) leading to short stature in adulthood. We hypothesized that the down-regulation of GH receptor (GHR) gene expression could be involved in growth failure of children with JIA.


METHODS
In 18 (12 F and 6 M) prepubertal JIA patients and 13 age- and sex-matched healthy children, we evaluated serum growth-promoting factors and inflammatory indexes. We also measured GHR gene expression, by real-time PCR, in lymphocytes of patients and controls. All parameters were evaluated in patients before and after treatment of JIA.


RESULTS
The most interesting (p = 0.007) result was the increase in GHR mRNA expression in all JIA patients. Moreover, we observed a significant (p = 0.0156) decrease in IL-6 levels in JIA patients after 2 years of therapy (19.37 ± 41.01) with respect to basal values (90.84 ± 124.71). On the contrary, IGF-I significantly (p = 0.0005) increased to a mean SDS value of 0 (range -1.69 to +1.70 SDS) with respect to values at disease onset (-0.64 SDS).


CONCLUSIONS
Our preliminary data suggest that the restoration of both GHR gene expression and IGF-I secretion correlate with inactive disease in JIA children.
Pediatrics Department Bambino Gesù Children's Hospital, Rome, Italy.
Elena
E
Bozzola
Sara
S
Pagani
Cristina
C
Meazza
Elisabetta
E
Cortis
Daniela
D
Lisini
Kamilia
K
Laarej
Mauro
M
Bozzola
D000886:Anthropometry; D001171:Arthritis, Juvenile / Q000378:metabolism* / Q000628:therapy; D016022:Case-Control Studies; D002648:Child; D005260:Female; D015870:Gene Expression; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D011986:Receptors, Somatotropin / Q000097:blood / Q000235:genetics / Q000378:metabolism*
D011986:Receptors, Somatotropin; D007334:Insulin-Like Growth Factor I