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Cell migration is centrally involved in a myriad of physiological processes, including morphogenesis, wound healing, tissue repair, and metastatic growth. The bioenergetics that underlie migratory behavior are not fully understood, in part because of variations in cell culture media and utilization of experimental cell culture systems that do not model physiological connective extracellular fibrous networks. In this study, we evaluated the bioenergetics of C2C12 myoblast migration and force production on fibronectin-coated nanofiber scaffolds of controlled diameter and alignment, fabricated using a nonelectrospinning spinneret-based tunable engineered parameters (STEP) platform. The contribution of various metabolic pathways to cellular migration was determined using inhibitors of cellular respiration, ATP synthesis, glycolysis, or glucose uptake. Despite immediate effects on oxygen consumption, mitochondrial inhibition only modestly reduced cell migration velocity, whereas inhibitors of glycolysis and cellular glucose uptake led to striking decreases in migration. The migratory metabolic sensitivity was modifiable based on the substrates present in cell culture media. Cells cultured in galactose (instead of glucose) showed substantial migratory sensitivity to mitochondrial inhibition. We used nanonet force microscopy to determine the bioenergetic factors responsible for single-cell force production and observed that neither mitochondrial nor glycolytic inhibition altered single-cell force production. These data suggest that myoblast migration is heavily reliant on glycolysis in cells grown in conventional media. These studies have wide-ranging implications for the causes, consequences, and putative therapeutic treatments aimed at cellular migration.
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Low‐Glucose Culture Conditions Bias Neuronal Energetics Towards Oxidative Phosphorylation
Neurons are almost exclusively cultured in media containing glucose at much higher concentrations than found in the brain. To test whether these “standard” hyperglycemic culture conditions affect neuronal respiration relative to near‐euglycemic conditions, we compared neuronal cultures grown with minimal glial contamination from the hippocampus and cortex of neonatal C57BL/6NCrl mice in standard commercially available media (25 mM Glucose) and in identical media with 5 mM glucose. Neuronal growth in both glucose concentrations proceeded until at least 14 days in vitro, with similar morphology and synaptogenesis. Neurons grown in high glucose were highly dependent on glycolysis as their primary source of ATP, measured using ATP luminescence and cellular respirometry assays. In contrast, neurons grown in 5 mM glucose showed a more balanced dependence on glycolysis and mitochondrial oxidative phosphorylation (OXPHOS), greater reserve mitochondrial respiration capacity, and increased mitochondrial population relative to standard media. Our results show that neurons cultured in artificially high glucose‐containing media preferentially use glycolysis, opposite to what is known for neurons in vivo as the primary pathway for ATP maintenance. Changes in gene and protein expression levels corroborate these changes in function and additionally suggest that high glucose culture media increases neuronal inflammation. We suggest using neuronal culture systems in 5 mM glucose to better represent physiologically relevant neuronal respiration.
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- Award ID(s):
- 1943514
- PAR ID:
- 10616087
- Editor(s):
- Lawrence, Andrew
- Publisher / Repository:
- John Wiley & Sons Ltd on behalf of International Society for Neurochemistry
- Date Published:
- Journal Name:
- Journal of Neurochemistry
- Volume:
- 169
- Issue:
- 6
- ISSN:
- 0022-3042
- Subject(s) / Keyword(s):
- cell culture glucose mitochondrial respiration neurobasal media neuronal bioenergetics primary mouse neuron
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/jnc.70125
