April - June 2008, Volume 4, Issue 2

Catrina SB, Botusan I, Cucu C, Radian S, Caragheorgheopol A, Coculescu M

IGF-1 levels in the cerebrospinal fluid in patients with acromegaly

Acta Endo (Buc) 2008, 4 (2): 143-150
doi: 10.4183/aeb.2008.143

IGF-I (Insulin like growth factor-I) plays a definitive role in the central nervous system (CNS) by modulating neuronal regeneration and survival. The local production of IGF-I in CNS has been demonstrated, but the contribution of circulating IGF-I transported through blood-brain barrier (BBB) has been just suggested in animals. There is currently no data available concerning IGF-I transport in CNS in humans. In order to investigate the passage of IGF-I over BBB in humans we have simultaneously measured the IGF-I and GH levels in serum and CSF in 25 patients with active acromegaly. IGF-I and GH levels in CSF were lower than in serum (2.2 ? 0.24 ng/mL vs 686.6 ? 46.83 ng/mL for IGF-I and 2.13 ? 0.627 mU/l vs 58.8 ? 15.86 mU/L for GH). However, both IGF-I and GH serum levels correlated with their CSF levels (r= 0.4, p<0.05 for IGF-I and r= 0.651, p= 0.006 for GH), suggesting that BBB is permeable for both hormones. In conclusion, we demonstrate the correlation of the IGF-I levels in serum and CSF, providing indirect evidence for IGF-I passage through BBB.

Keywords: IGF-I, cerebrospinal fluid, acromegaly, GH, blood-brain-barrier

Correspondence: Sergiu-Bogdan Catrina MD, PhD, Department of Molecular Medicine and Surgery, Karolinska Institutet, Rolf Luft Center for Diabetes and Endocrinology, Karolinska Hospital, L1:01, Stockholm, S-17176, Stockholm Sweden, email: Sergiu-Bogdan.Catrina@ki.se