Abstract
No therapies currently exist for intellectual disability in Down syndrome (DS). In view of its similarities with DS, including learning and memory (L&M) defects, the Ts65Dn mouse model of DS is widely used for the design of therapy. 7,8-dihydroxyflavone (7,8-DHF), a flavonoid that targets the tropomyosin-related kinase B (TrkB) receptor of brain-derived neurotrophic factor (BDNF), exerts positive effects in various brain disease models. Based on previous demonstration that administration of 7,8-DHF in the postnatal period P3-P15 restores hippocampal neurogenesis and spinogenesis, we sought to establish whether these effects translate into behavioral benefits after treatment cessation. We found that Ts65Dn mice treated with 7,8-DHF (5.0 mg/kg/day) during postnatal days P3-P15 did not show any L&M improvement at one month after treatment cessation, indicating that the effects of 7,8-DHF on the brain are ephemeral. Based on evidence that chronic treatment with 7,8-DHF in juvenile Ts65Dn mice restores L&M, we sought to establish whether a similar effect is elicited in adulthood. We found that Ts65Dn mice treated with 7,8-DHF (5.0 mg/kg/day) for about 40 days starting from 4 months of age did not show any improvement in L&M. The results suggest that timing of therapy with 7,8-DHF is a critical issue for attainment of positive effects on the brain.
Highlights
Down syndrome (DS), a relatively high-incidence (1:750/1000) genetic disorder due to triplication of chromosome 21 (Chr21), is characterized by various medical problems and intellectual disability (ID).The gene burden, due to triplication of Chr21, disrupts a number of developmental processes, including brain development
Ts65Dn mice were treated from postnatal day 3 (P3) to P15 and their behavior was examined at one month after treatment cessation
We evaluated swimming speed, in order to establish whether possible speed differences may affect the outcome of the Morris Water Maze (MWM) test
Summary
Down syndrome (DS), a relatively high-incidence (1:750/1000) genetic disorder due to triplication of chromosome 21 (Chr21), is characterized by various medical problems and intellectual disability (ID). The gene burden, due to triplication of Chr, disrupts a number of developmental processes, including brain development. The severity of ID may be variable, in most cases, individuals with DS cannot lead an autonomous life. ID represents a concern for families and society. Regarding the causes of ID, neurogenesis reduction during the earliest life stages and impaired dendritic development are the factors that most likely play a prominent role (see [1,2]). No therapies are currently available for the amelioration of ID in individuals with DS
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
