| First Author | Zegarra-Valdivia JA | Year | 2021 |
| Journal | Front Aging Neurosci | Volume | 13 |
| Pages | 682388 | PubMed ID | 34539376 |
| Mgi Jnum | J:311190 | Mgi Id | MGI:6765660 |
| Doi | 10.3389/fnagi.2021.682388 | Citation | Zegarra-Valdivia JA, et al. (2021) Reduced Insulin-Like Growth Factor-I Effects in the Basal Forebrain of Aging Mouse. Front Aging Neurosci 13:682388 |
| abstractText | It is known that aging is frequently accompanied by a decline in cognition. Furthermore, aging is associated with lower serum IGF-I levels that may contribute to this deterioration. We studied the effect of IGF-I in neurons of the horizontal diagonal band of Broca (HDB) of young (</=6 months old) and old (>/=20-month-old) mice to determine if changes in the response of these neurons to IGF-I occur along with aging. Local injection of IGF-I in the HDB nucleus increased their neuronal activity and induced fast oscillatory activity in the electrocorticogram (ECoG). Furthermore, IGF-I facilitated tactile responses in the primary somatosensory cortex elicited by air-puffs delivered in the whiskers. These excitatory effects decreased in old mice. Immunohistochemistry showed that cholinergic HDB neurons express IGF-I receptors and that IGF-I injection increased the expression of c-fos in young, but not in old animals. IGF-I increased the activity of optogenetically-identified cholinergic neurons in young animals, suggesting that most of the IGF-I-induced excitatory effects were mediated by activation of these neurons. Effects of aging were partially ameliorated by chronic IGF-I treatment in old mice. The present findings suggest that reduced IGF-I activity in old animals participates in age-associated changes in cortical activity. |
