The Wnt/Ca²⁺signaling pathway is essential for the regeneration of GABAergic neurons in planarianDugesia japonica

Abstract

The nervous system is one of the most complex and fascinating organ systems in the metazoan. Neural networks regulate many aspects of animal physiology and behavior. The longheld doctrine that neurons are only produced in the embryo 1,2 has been challenged by the discovery that neurogenesis persists in the central nervous system (CNS) of adult animals. 3 It is now accepted that adult neurogenesis is a widespread phenomenon in different metazoans. 4,5 As vertebrates, zebrafish have shown that adult neurogenesis is along the entire rostral-caudal axis of the brain 6 and when their CNS

U73122 and m-3M3FBS Regulate the GABAergic Neuron Regeneration via PLCβ in Planarian Dugesia japonica

“…Many studies have shown that m-3M3FBS is a selective PLC activator in various systems, including snail neurons [39], neuronal cells [40], and mouse taste cells [41]. Our previous research found that down-regulation of DjPLCβ can lead to defects in regenerated brains resulting in partial brain deletion, and failure of posterior brain lateral branches to regenerate [32]. In this study, we demonstrate that the U73122 strongly inhibits brain regeneration in planarian (Figs.…”

“…There are no studies on the relationship between PLC and GABAergic neuron regeneration in vertebrates. Our previous research found that down-regulation of DjPLCβ can affect the brain regeneration and decrease the number of GABAergic neurons in planarian [32]. Our results showed that DjGAD mRNA and protein were decreased in U73122-treated planarian compared with control animals (Figs.…”

“…The PLC/IP 3 R/PKC pathway has been shown to be necessary for ethanol to increase spontaneous GABA release, suggesting that PLC is required for GABA synthesis [42]. We have proved that down-reg- ulation of DjPLCβ can lead to a significant decrease in GABAergic neurons in regenerated planarian [32]. To confirm that U73122 and m-3M3FBS might affect the regeneration of GABAergic neurons at 5, 7, and 10 days after amputation, the neurotransmitter-synthesizing enzymeglutamic acid decarboxylase (DjGAD) was used as a neuron marker in WISH analyses in order to measure the numbers of neurons in decapitated planarians.…”

“…We have demonstrated that the expression level of DjPLCβ mRNA in the brain during the regeneration decreases after decapitation. Reduction of DjPLCβ(RNAi) at the posterior region of the new brain was correlated with a failure to regenerate lateral branches during planarian regeneration [32]. To deter-mine whether U73122 and m-3M3FBS affected regeneration, immunostaining with anti-SYNORF1 antibody, revealing synapses [36] revealed that U73122 treatment affected synapses at 7 and 10 days of regeneration.…”

“…Knockdown of DjPLCβ led to defects in regenerated brains including brain partial deletions and lateral branches, which could not regenerate. Furthermore, the expressions of GAD and the number of GABAergic neurons decreased [32].…”