Poster Topical Area: Neurobiology

Location: Hall D

Poster Board Number: 724

P16-022 - Comparison of Supplemental Magnesium Forms for CNS Uptake in Rats

Monday, Jun 11
8:00 AM – 3:00 PM

Objectives: Magnesium (Mg) is an essential mineral that supports brain health and cognitive function by modulating neurotransmitter release, neuronal excitability, and synaptic plasticity. Mg is ubiquitous in food and available in numerous chelated forms as dietary supplements, but it is not known if any forms offer enhanced delivery to the central nervous system. Therefore, we sought to compare how different Mg forms affect plasma and cerebrospinal fluid (CSF) levels of Mg following intragastric administration for 14 days.

Methods: Male Sprague Dawley rats (150-175 g, n=5/group) with ad libitum access to water and chow (0.2% Mg) were orally gavaged 2x/d for 14 d with either water vehicle or 50 mg/kg/d of the following Mg chelates: glycinate, glycinate (tablet), malate, citrate, lactate dehydrate, bisglycinate, threonate, lactate, glycerophosphate, orotate, or taurate. At the end of the study, animals were anesthetized and samples were collected for biochemical assessments of Mg levels. CSF was extracted from cisterna magna and whole blood samples (cardiac puncture) were separated into plasma and red blood cells (RBCs). Free Mg from CSF and plasma were measured by ion chromatography and RBC Mg was measured spectrophotometrically. Data were analyzed by ANOVA followed by Fisher's post-hoc comparison.

Results: Compared to vehicle, body weight was moderately reduced over days 2-8 in citrate and bisglycinate groups but not different for remaining days. After 14 d treatment, there were no group differences in plasma or RBC Mg levels. In CSF, Mg levels were lower in citrate, lactate (dihydrate), and bisglycinate groups compared to vehicle. Although not statistically different from vehicle, taurate CSF Mg was significantly greater than all Mg groups except glycinate (tablet) and malate.

Conclusions: In this proof of concept study, oral administration of Mg taurate for 14 consecutive days resulted in increased CSF levels of Mg in comparison to several other supplemental forms of Mg. These findings merit further study to evaluate Mg taurate's potential superiority as a brain-targeted Mg form.

Funding Source: This study was funded by Metagenics.

CoAuthors: Milene Brownlow – Metagenics; Taleen Hanania – Psychogenics; Nikky Contractor – Metagenics

Christopher Moulton

Therapeutic Platform Lead, Cognition & Special Projects
Aliso Viejo, California