Increased type III procollagen in serum and skin of patients with amyotrophic lateral sclerosis

Objectives - Collagen abnormalities of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerni ng the aminoterminal propeptide of type III procollagen (PIIIP) and type II I collagen in ALS. The aim of this study is to measure PIIIP, a precursor f orm of type III collagen, in skin and serum of ALS. Material ann methods - We studied PIIIP immunoreactivity of skin and measured serum levels of PIII P in ALS patients, and the results were compared with those of control subj ects. Results - Collagen bundles in the dermis of ALS were immunohistochemi cally strongly positive for PIIIP as compared with those of controls. The o ptical density of PIIIP immunostaining reactivity in ALS patients was signi ficantly higher than in controls, and was significantly increased with dura tion of illness. Serum PIIIP levels in patients with ALS were significantly increased as compared with those in diseased control subjects and those in healthy control ones, and were positively and significantly associated wit h duration of illness. There was an appreciable positive correlation betwee n concentrations of serum PIIIP and the density of PIIIP immunoreactivity o f skin in ALS patients. Conclusion - These data suggest that a metabolic al teration of PIIIP may take place in the skin of ALS and the increased level s of serum PIIIP may reflect the increased PIIIP immunoreactivity of skin i n ALS.