The expression and preliminary functional exploration of Olfaxin in the central nervous system of mice

Prune homolog 2 (Drosophila) (PRUNE2) protein has five subtypes, four of which have been reported to play important roles in the central nervous system (CNS), but the fifth ,Olfaxin still remains unclear. Therefore, this study aims to investigate Olfaxin expression in the CNS of mouse. In vivo and in vitro , experiments indicate Olfaxin is expressed in the olfactory bulb (OB) neurons: glutamatergic neuron marked by Excitatory Amino Acid Carrier 1 (EAAC1), GABA-ergic neuron marked by Glutamic Acid Decarboxylase 67 (GAD67), Cholinergic neuron marked by Choline Acetyltransferase (ChAT) and dopaminergic neuron marked by Tyrosine Hydroxylase (TH). While,in the OB glia, its expression pattern differed between in vivo and in vitro settings. Under low - glucose conditions, Olfaxin and Monocarboxylate Transporter 1 (MCT1) expression increased in microglia, suggesting a role in energy metabolism. In an Alzheimer's disease (AD) mouse model, Olfaxin expression varied in different brain regions. These results indicate that Olfaxin may influence AD progression, possibly through microglial energy metabolism, although the underlying mechanisms remain to be further investigated.