Distinct roles of AdipoR1 and AdipoR2 in modulating neuronal firing homeostasis in response to adiponectin and AdipoRon
摘要
The regulation of neuronal network activity depends on interactions between intrinsic circuit mechanisms and metabolic signals. Adiponectin (APN) is a peripheral adipokine whose receptors are present in the central nervous system (CNS), but whether APN/APN receptor (AdipoR) signaling shapes network-level firing dynamics remains incompletely understood.
MethodsWe used multi-electrode array (MEA) recordings in WT, APN-KO, AdipoR1-KO, and AdipoR2-KO primary cortical cultures to examine APN/AdipoR-associated regulation of network-level firing dynamics. Genetic and pharmacological experiments with native APN and the synthetic AdipoR agonist AdipoRon (AR) were complemented by dose-response, washout, time-matched control, developmental-control, ELISA, and bicuculline-challenge assays in neuronal cultures and human forebrain organoids.
ResultsAR modulated WT network activity in a concentration-dependent manner, with strong suppression at higher concentrations and smaller or bidirectional effects at lower concentrations. APN was detectable in neuron-conditioned medium, supporting local APN-related signaling in the culture system. APN-KO and AdipoR1-KO cultures showed increased firing-rate-related activity relative to matched controls, whereas AdipoR2-KO cultures showed reduced basal firing. Native APN and AR produced distinct temporal profiles. In bicuculline-disinhibited networks, AR suppressed network firing, whereas APN did not acutely silence the networks in the same manner.
ConclusionThese data support a role for AdipoR signaling in neuronal network balance and indicate non-identical contributions of AdipoR1 and AdipoR2 to firing-rate control, bursting, and synchrony. Collectively, these findings identify AdipoR1 and AdipoR2 as differential regulators of firing homeostasis and establish a metabolic pathway for the homeostatic control of neuronal network excitability.