Aging alters mechanisms underlying voluntary movements in spinal motor neurons of mice, primates, and humans.

ABSTRACT: Spinal motor neurons have been implicated in the loss of motor function that occurs with advancing age. However, the cellular and molecular mechanisms that impair the function of these neurons during aging remain unknown. Here, we show that motor neurons do not die in old female and male mice, rhesus monkeys, and humans. Instead, these neurons selectively and progressively shed excitatory synaptic inputs throughout the soma and dendritic arbor during aging. Thus, aged motor neurons contain a motor circuitry with a reduced ratio of excitatory to inhibitory synapses that may be responsible for the diminished ability to activate motor neurons to commence movements. An examination of the motor neuron translatome (ribosomal transcripts) in male and female mice reveals genes and molecular pathwa

SUBMITTER: Castro RW 

PROVIDER: S-EPMC10243831 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature