Type

Other / n/a

Authors

Jochen HM Prehn
Heinrich J Huber
Ujval Anilkumar
Heiko Düssmann
Niamh M Connolly

Subjects

Pharmacology

Topics
excitotoxicity single cell imaging bioenergetics physics receptors glutamate oxygen physiology protein kinase

Single-Cell Imaging of Bioenergetic Responses to Neuronal Excitotoxicity and Oxygen and Glucose Deprivation (2014)

Abstract Excitotoxicity is a condition occurring during cerebral ischemia, seizures, and chronic neurodegeneration. It is characterized by overactivation of glutamate receptors, leading to excessive Ca2+/Na+ influx into neurons, energetic stress, and subsequent neuronal injury.We and others have previously investigated neuronal populations to study how bioenergetic parameters determine neuronal injury; however, such experiments are often confounded by population-based heterogeneity and the contribution of effects of non-neuronal cells. Hence, we here characterized bioenergetics during transient excitotoxicity in rat and mouse primary neurons at the single-cell level using fluorescent sensors for intracellular glucose, ATP, and activation of the energy sensor AMP-activated protein kinase (AMPK). We identified ATP depletion and recovery to energetic homeostasis, along withAMPKactivation, as surprisingly rapid and plastic responses in two excitotoxic injury paradigms. We observed rapid recovery of neuronal ATP levels also in the absence of extracellular glucose, or when glycolytic ATP production was inhibited, but found mitochondria to be critical for fast and complete energetic recovery. Using an injury model of oxygen and glucose deprivation, we identified a similarly rapid bioenergetics response, yet with incompleteATPrecovery and decreasedAMPKactivity. Interestingly, excitotoxicity also induced an accumulation of intracellular glucose, providing an additional source of energy during and after excitotoxicity-induced energy depletion. We identified this to originate from extracellular, AMPKdependent glucose uptake and from intracellular glucose mobilization. Surprisingly, cells recovering their elevated glucose levels faster to baseline survived longer, indicating that the plasticity of neurons to adapt to bioenergetic challenges is a key indicator of neuronal viability.
Collections Ireland -> Royal College of Surgeons in Ireland -> Physiology and Medical Physics Articles
Ireland -> Royal College of Surgeons in Ireland -> Department of Physiology and Medical Physics

Full list of authors on original publication

Jochen HM Prehn, Heinrich J Huber, Ujval Anilkumar, Heiko Düssmann, Niamh M Connolly

Experts in our system

1
Jochen H M Prehn
Royal College of Surgeons in Ireland
Total Publications: 206
 
2
Heinrich J Huber
Royal College of Surgeons in Ireland
Total Publications: 39
 
3
Ujval Anilkumar
Royal College of Surgeons in Ireland
Total Publications: 14
 
4
Heiko Düssmann
Royal College of Surgeons in Ireland
Total Publications: 45
 
5
Niamh M C Connolly
Royal College of Surgeons in Ireland
Total Publications: 14