TY - JOUR
T1 - Heterogenous response to aging of astrocytes in murine Substantia Nigra pars compacta and pars reticulata
AU - Bondi, Heather
AU - Chiazza, Fausto
AU - Masante, Irene
AU - Bortolotto, Valeria
AU - Canonico, Pier Luigi
AU - Grilli, Mariagrazia
N1 - Publisher Copyright:
© 2022
PY - 2023/3
Y1 - 2023/3
N2 - Currently, little is known about the impact of aging on astrocytes in substantia nigra pars compacta (SNpc), where dopaminergic neurons degenerate both in physiological aging and in Parkinson's disease, an age-related neurodegenerative disorder. We performed a morphometric analysis of GFAP+ astrocytes in SNpc and, for comparison, in the pars reticulata (SNpr) of young (4–6 months), middle-aged (14–17 months) and old (20–24 months) C57BL/6J male mice. We demonstrated an age-dependent increase of structural complexity only in astrocytes localized in SNpc, and not in SNpr. Astrocytic structural remodelling was not accompanied by changes in GFAP expression, while GFAP increased in SNpr of old compared to young mice. In parallel, transcript levels of selected astrocyte-enriched genes were evaluated. With aging, decreased GLT1 expression occurred only in SNpc, while xCT transcript increased both in SNpc and SNpr, suggesting a potential loss of homeostatic control of extracellular glutamate only in the subregion where age-dependent neurodegeneration occurs. Altogether, our results support an heterogenous morphological and biomolecular response to aging of GFAP+ astrocytes in SNpc and SNpr.
AB - Currently, little is known about the impact of aging on astrocytes in substantia nigra pars compacta (SNpc), where dopaminergic neurons degenerate both in physiological aging and in Parkinson's disease, an age-related neurodegenerative disorder. We performed a morphometric analysis of GFAP+ astrocytes in SNpc and, for comparison, in the pars reticulata (SNpr) of young (4–6 months), middle-aged (14–17 months) and old (20–24 months) C57BL/6J male mice. We demonstrated an age-dependent increase of structural complexity only in astrocytes localized in SNpc, and not in SNpr. Astrocytic structural remodelling was not accompanied by changes in GFAP expression, while GFAP increased in SNpr of old compared to young mice. In parallel, transcript levels of selected astrocyte-enriched genes were evaluated. With aging, decreased GLT1 expression occurred only in SNpc, while xCT transcript increased both in SNpc and SNpr, suggesting a potential loss of homeostatic control of extracellular glutamate only in the subregion where age-dependent neurodegeneration occurs. Altogether, our results support an heterogenous morphological and biomolecular response to aging of GFAP+ astrocytes in SNpc and SNpr.
KW - Aging
KW - Astrocytes
KW - GLT1
KW - Glial plasticity
KW - Morphometry
KW - Substantia nigra
UR - https://www.scopus.com/pages/publications/85146075818
U2 - 10.1016/j.neurobiolaging.2022.12.010
DO - 10.1016/j.neurobiolaging.2022.12.010
M3 - Article
SN - 0197-4580
VL - 123
SP - 23
EP - 34
JO - Neurobiology of Aging
JF - Neurobiology of Aging
ER -