Decreased levels of aquaporin-4 in the cerebrospinal fluid of patients with idiopathic intracranial hypertension

Abstract

Idiopathic intracranial hypertension is characterized by increased intracranial pressure. Its pathogenesis is largely unknown. Aquaporins may play a role in the homeostasis of cerebrospinal fluid. We aimed to elucidate the role of aquaporins in idiopathic intracranial hypertension by measuring the level of aquaporin-1 and aquaporin-4 in the cerebrospinal fluid and plasma of 28 patients and 29 controls by enzyme-linked immunosorbent assay. The adipokines leptin and retinol-binding protein 4 were also measured. We found a reduction in aquaporin-4 in the cerebrospinal fluid of patients. Leptin levels were increased in the cerebrospinal fluid and plasma of patients and were correlated with weight, body mass index and body fat. There was no difference between patients and controls in the levels of aquaporin-1 and retinol-binding protein 4. Our data suggest that an imbalance of aquaporin-4 in the cerebrospinal fluid of patients with idiopathic intracranial hypertension may contribute to the pathogenesis of this disorder.