Increased expression of laminin 1 in the skin of amyotrophic lateral sclerosis

Abnormalities of collagen and glycosaminoglycans of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerning laminin in ALS. The aim of this study is to evaluate laminin 1 immunohistochemistry of skin in ALS patients. We studied laminin 1 immunoreactivity of skin from 17 patients with ALS, 17 patients with other neurological or muscular diseases (control group A) and 10 patients without neurological or muscular disorders (control group B). The dermis, the epithelial basement membrane of the epidermal layer and the basement membrane of skin appendages and blood vessels of skin in ALS patients were significantly higher than in control groups A and B, and showed a significant positive correlation with the duration of illness in the optical density for laminin 1 immunoreactivity. In addition, there was an appreciable positive relationship in the laminin 1 immunoreactivity between the dermis and the basement membrane in ALS patients. These data suggest that alterations of laminin 1 in the skin of ALS patients could be related to the pathogenesis of ALS and may contribute to changes in the mechanical properties of the skin, resulting in the absence of bedsores in ALS patients.