CSF insulin-like growth factor-1 in infantile neuronal ceroid lipofuscinosis

Background: Infantile neuronal ceroid lipofuscinosis (INCL) is a progressiv e encephalopathy in which the patients are severely disabled by the age of 3 years. It is characterized by cerebral atrophy, selective loss of cortica l neurons, and secondary loss of axons and myelin sheaths of the white matt er. INCL has been shown to result from a palmitoyl protein thioesterase def iciency. The authors suggested that insulin-like growth hormones and apopto sis might play a role in the pathogenesis of INCL. Methods: The authors mea sured insulin-like growth factor-1 (IGF-1) and IGF binding protein 3 (IGFBP -3) in the CSF of patients with INCL by radioimmunoassay at an early stage when myelin was starting to diminish. Results: The authors found low CSF IG F-1 but normal IGFBP-3 in patients with INCL compared with control subjects . Also, they observed apoptotic cell death in biopsies of INCL patients. Co nclusions: Because the IGF system seems to be important for early brain dev elopment, myelination, and neuroprotection, the authors suggest that the pa thology in INCL may be associated with low CSF IGF-1.