Regulation of structural and functional synapse density by L-threonate through modulation of intraneuronal magnesium concentration.
Level 5 - mechanism / opinion, no new human data
Preclinical in vitro and mechanistic bench research
PubMed 27178134 · doi:10.1016/j.neuropharm.2016.05.006
What was done
The authors investigated the cellular mechanisms of L-threonate, a component of L-threonic acid magnesium salt (L-TAMS). They evaluated cerebrospinal fluid (CSF) threonate levels after oral L-TAMS administration and examined the effects of threonate—compared to other magnesium anions—on intracellular magnesium, NR2B-containing NMDAR expression, mitochondrial membrane potential, and synapse density in cultured rat hippocampal neurons and human neural stem cell-derived neurons. The role of glucose transporters (GLUTs) in mediating these effects was also tested.
What was found
Threonate was detected in baseline CSF and increased after oral L-TAMS treatment. In cultured hippocampal neurons, threonate directly raised intracellular magnesium, upregulated NR2B-containing NMDAR expression, boosted mitochondrial membrane potential, and increased functional synapse density, whereas other magnesium anions did not. These actions were mediated via glucose transporters. Upregulation of synapse density was also replicated in human neural stem cell-derived neurons. The abstract reports no numerical values or effect sizes.
Why it matters
This study provides a cellular and transport-mediated explanation for how L-threonate facilitates neuronal magnesium entry to support synapse density, distinguishing it from conventional magnesium formulations.
Limits
The abstract provides no quantitative data, sample sizes, or statistical confidence metrics. The findings derive from in vitro cell cultures and animal CSF measurements, which cannot establish clinical efficacy or human in vivo pharmacokinetics.
Cited by
- supports Magnesium L-threonate crosses the blood-brain barrier more efficiently than other forms of magnesium.