Male hormone for the treatment of telomere diseases

• Grant number: 16/17900-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2017
• End date: March 31, 2019
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Rodrigo do Tocantins Calado de Saloma Rodrigues
• Grantee: Renan Carvalho Albino
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Telomeres are repeated sequences of nucleotides coated by specialized proteins that are located at the end of linear chromosomes with the function to protect them from damages in the genetic material. Telomerase is an enzyme responsible for the synthesis and maintenance of telomeres, fundamentally important in high rate proliferative cells such as stem cells and hematopoietic progenitors. When there is a damage in the formation of the telomere complex, there is excessive telomeric shortening and thus the diseases related to telomere shortening as aplastic anemia and dyskeratosis congênita appear. Moreover, telomeropathys are associated with idiopathic pulmonary fibrosis and cirrhosis. In vitro studies indicate that telomerase expression can be modulated by sexual hormones, potentially decreasing telomere erosion. This occurs because the promoter region of the TERT (gene of the telomerase) contains at least two binding sites for the estrogen receptor. Thus, increased expression of telomerase modulated by the hormone improves the events of formation and maintenance of the telomeres and, therefore must have effects on disease progression. The present study aims at assessing the effects of the treatment of patients with telomere diseases with nandrolone decanoate on telomere length of peripheral blood leukocytes and disease progression. Nandrolone decanoate is administered intramuscularly every two weeks, 5 mg/kg/dose. Patients will be followed at landmark visits and will be evaluated for drug tolerability, telomere length, and clinical improvement. Patients who cannot tolerate the initial dose will have the dose reduced or eventually stopped. Thereby, with the aid of androgens, it can increases the telomerase activity, reducing telomeric shortening rate and consequent pancytopenia, which lately should promote increased proliferation and tissue regeneration. (AU)