Potential roles of telomeres and telomerase in neurodegenerative diseases

Telomeres, protective DNA-protein complexes at the end of eukaryotic linear chromosomes, play pivotal roles in the maintenance of genomic stability during cell division. When telomeres are severely shortened, cells stop dividing and die, consequently leading to tissues degeneration. Concretely, replicative senescence and genomic damage are generally accompanied with telomere shortening, which may be a potential contributor in the pathogenesis of neurological disorders. Regardless of occasional negative findings, accelerated telomere erosion is routinely found in neurodegenerative diseases and has been believed to be positively correlated with the severity of neurodegenerative diseases. As considerable knowledge of telomeres and telomerase continues to accumulate, telomerase is increasingly being recognized as a promising therapeutic target for neurodegenerative disease. Until now, strong evidence has accumulated that activated telomerase is responsible for telomere elongation that may be sufficient to prevent "mother cells" from replicative aging, and besides, telomerase activators exhibit remarkable neuroprotective effects through the prolongation of telomere length and the promotion of neuronal survival as well as proliferation. Therefore, a consensus is emerging that the activation of telomerase, promoted by peptides, natural herbal extracts, small molecules compounds and others, represents a novel promising treatment strategy for neurodegenerative diseases.