Transforming growth factor-β plasma levels and its role in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive muscle paralysis. Respiratory complications are the main cause of death in ALS. For this reason, initial respiratory status and its decline over disease progression are strong independent predictors of survival. Riluzole, a glutamatergic neurotransmission inhibitor, is the only drug that has shown to extend survival. Therefore, both novel molecular biomarkers and treatment strategies are needed. Transforming growth factor-β (TGF-β) family cytokines are important regulators of cell fate affecting both neurogenesis and neurodegeneration. Several studies demonstrate that TGF-β signalling protects neurons from glutamate-mediated excitotoxicity, a recognized mechanism underlying the pathogenesis of various neurodegenerative disorders such as ALS. Recent studies report dysregulations of the TGF-β system as a common feature of neurodegenerative disorders. The upregulation of this system has been linked with ALS progression. We have quantified TGF-β1, TGF-β2 and TGF-β3 serum levels in 23 ALS patients and 12 healthy controls, our preliminary results support the hypothesis that TGF-β3 levels can be a marker disease severity ALS. Further results are necessary to confirm this hypothesis.