Activation of the 5-HT1A Receptor by Eltoprazine Restores Mitochondrial and Motor Deficits in a Drosophila Model of Fragile X Syndrome

Int J Mol Sci. 2024 Aug 13;25(16):8787. doi: 10.3390/ijms25168787.

Abstract

Neurons rely on mitochondrial energy metabolism for essential functions like neurogenesis, neurotransmission, and synaptic plasticity. Mitochondrial dysfunctions are associated with neurodevelopmental disorders including Fragile X syndrome (FXS), the most common cause of inherited intellectual disability, which also presents with motor skill deficits. However, the precise role of mitochondria in the pathophysiology of FXS remains largely unknown. Notably, previous studies have linked the serotonergic system and mitochondrial activity to FXS. Our study investigates the potential therapeutic role of serotonin receptor 1A (5-HT1A) in FXS. Using the Drosophila model of FXS, we demonstrated that treatment with eltoprazine, a 5-HT1A agonist, can ameliorate synaptic transmission, correct mitochondrial deficits, and ultimately improve motor behavior. While these findings suggest that the 5-HT1A-mitochondrial axis may be a promising therapeutic target, further investigation is needed in the context of FXS.

Keywords: FXS therapy; eltoprazine; intellectual disability; neuromuscular junction; serotonin; synaptic transmission.

MeSH terms

  • Animals
  • Disease Models, Animal*
  • Drosophila
  • Drosophila melanogaster / drug effects
  • Fragile X Syndrome* / drug therapy
  • Fragile X Syndrome* / metabolism
  • Mitochondria* / drug effects
  • Mitochondria* / metabolism
  • Motor Activity / drug effects
  • Piperazines / pharmacology
  • Receptor, Serotonin, 5-HT1A* / metabolism
  • Serotonin 5-HT1 Receptor Agonists / pharmacology
  • Serotonin 5-HT1 Receptor Agonists / therapeutic use
  • Synaptic Transmission / drug effects

Substances

  • Receptor, Serotonin, 5-HT1A
  • Piperazines
  • Serotonin 5-HT1 Receptor Agonists

Grants and funding

This work was initially supported by KUL Opening the Future (OTF), and continued under the support of Etat de Vaud, SNFS 310030-182651, and the Novartis Foundation for medical–biological research (#17C166) (Switzerland), along with PRIN-MUR 20227JA8R3 as granted to C.B. A.K.K. was the Autism Speaks Meixner Postdoctoral Fellowship (grant #9728) recipient and received funding from the Fondation Pierre Mercier.