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Vitamin D deficiency promotes accumulation of bioactive lipids and increased endocannabinoid tone in zebrafish.

ABSTRACT: Vitamin D is well known for its traditional role in bone mineral homeostasis; however, recent evidence suggests that vitamin D also plays a significant role in metabolic control. This study served to investigate putative linkages between vitamin D deficiency (VDD) and metabolic disruption of bioactive lipids by mass spectrometry imaging (MSI). Our approach employed infrared-matrix-assisted laser desorption electrospray ionization (IR-MALDESI) MSI for lipid metabolite profiling in 6-month-old zebrafish fed either a vitamin D-deficient (VDD) or a vitamin D-sufficient (VDS) diet. Using a lipidomics pipeline, we found that VDD zebrafish had a greater abundance of bioactive lipids (N-acyls, endocannabinoids (ECs), diacylglycerols/triacylglycerols, bile acids/bile alcohols, and vitamin D derivatives) suggestive of increased endocannabinoid tone compared to VDS zebrafish. Tandem mass spectrometry (MS²) was performed on several differentially expressed metabolites with sufficient ion abundances to aid in structural elucidation and provide additional support for MS¹ annotations. To confirm activation of the EC pathways, we subsequently examined expression of genes involved in EC biosynthesis, metabolism, and receptor signaling in adipose tissue and liver from VDD and VDS zebrafish. Gene expression changes were congruent with increased endocannabinoid tone, with VDD zebrafish demonstrating increased synthesis and metabolism of anandamide compared to VDS zebrafish. Taken together, our data suggest that VDD may promote accumulation of bioactive lipids and increased endocannabinoid tone in zebrafish.

SUBMITTER: Knuth MM

PROVIDER: S-EPMC8604674 | biostudies-literature |

REPOSITORIES: biostudies-literature

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