Faculty, Staff and Student Publications
Language
English
Publication Date
11-1-2023
Journal
The Journal of Nutrition
DOI
10.1016/j.tjnut.2023.10.016
PMID
37898335
PMCID
PMC10739780
PubMedCentral® Posted Date
10-28-2023
PubMedCentral® Full Text Version
Post-print
Abstract
Background: Regulation of mechanistic target of rapamycin complex 1 (mTORC1) plays an important role in aging and nutrition. For example, caloric restriction reduces mTORC1 signaling and extends lifespan, whereas nutrient abundance and obesity increase mTORC1 signaling and reduce lifespan. Skeletal muscle-specific knockout (KO) of DEP domain-containing 5 protein (DEPDC5) results in constitutively active mTORC1 signaling, muscle hypertrophy and an increase in mitochondrial respiratory capacity. The metabolic profile of skeletal muscle, in the setting of hyperactive mTORC1 signaling, is not well known.
Objectives: To determine the metabolomic and lipidomic signature in skeletal muscle from female and male wild-type (WT) and DEPDC5 KO mice.
Methods: Tibialis anterior (TA) muscles from WT and transgenic (conditional skeletal muscle-specific DEPDC5 KO) were obtained from female and male adult mice. Polar metabolites and lipids were extracted using a Bligh-Dyer extraction from 5 samples per group and identified and quantified by LC-MS/MS. Resulting analyte peak areas were analyzed with t-test, analysis of variance, and Volcano plots for group comparisons (e.g., WT compared with KO) and multivariate statistical analysis for genotype and sex comparisons.
Results: A total of 162 polar metabolites (organic acids, amino acids, and amines and acyl carnitines) and 1141 lipid metabolites were detected in TA samples by LC-MS/MS. Few polar metabolites showed significant differences in KO muscles compared with WT within the same sex group. P-aminobenzoic acid, β-alanine, and dopamine were significantly higher in KO male muscle whereas erythrose-4-phosphate and oxoglutaric acid were significantly reduced in KO females. The lipidomic profile of the KO groups revealed an increase of muscle phospholipids and reduced triacylglycerol and diacylglycerol compared with the WT groups.
Conclusions: Sex differences were detected in polar metabolome and lipids were dependent on genotype. The metabolomic profile of mice with hyperactive skeletal muscle mTORC1 is consistent with an upregulation of mitochondrial function and amino acid utilization for protein synthesis.
Keywords
DEPDC5, sexual dimorphism, skeletal muscle, metabolites, lipidomics
Published Open-Access
yes
Recommended Citation
Nielsen, Marisa C; Cerqueira, Filipe M; Kavuri, Sri Bharathi; et al., "Diverse Clinical Manifestations and Challenges of Mucormycosis: Insights From Serial Cases." (2023). Faculty, Staff and Student Publications. 748.
https://digitalcommons.library.tmc.edu/uthshis_docs/748