The High Costs of Low-Grade Inflammation: Persistent Fatigue as a Consequence of Reduced Cellular-Energy Availability and Non-adaptive Energy Expenditure. — CFSMEATLAS
The High Costs of Low-Grade Inflammation: Persistent Fatigue as a Consequence of Reduced Cellular-Energy Availability and Non-adaptive Energy Expenditure.
Lacourt, Tamara E, Vichaya, Elisabeth G, Chiu, Gabriel S et al. · Frontiers in behavioral neuroscience · 2018 · DOI
Quick Summary
This study explores why people with ME/CFS experience persistent fatigue by examining how inflammation in the body may damage cells' ability to produce energy. The researchers propose that chronic inflammation forces cells to switch to a less efficient energy-production method, while at the same time the body may be spending energy at rates it cannot sustain, creating an energy crisis. Sleep problems and disrupted body rhythms may also play a role in this imbalance.
Why It Matters
This work provides a testable mechanistic framework for understanding ME/CFS fatigue rooted in cellular energy metabolism and inflammation, moving beyond descriptive symptom accounts. If accurate, it suggests that interventions targeting metabolic switching, mitochondrial function, sleep, and circadian alignment could address fatigue at its physiological source rather than symptomatically.
Observed Findings
Low-grade inflammation is associated with a metabolic switch from efficient oxidative phosphorylation to inefficient aerobic glycolysis.
Chronic inflammation increases reactive oxygen species and reduces insulin sensitivity, limiting glucose availability to cells.
Chronic low-grade inflammation is associated with increased willingness to exert effort, despite reduced cellular energy.
Circadian-rhythm disruption and sleep disturbances co-occur with inflammation and fatigue.
Behavioral energy expenditure appears to exceed cellular-energy availability in patients with persistent fatigue.
Inferred Conclusions
Low-grade inflammation impairs cellular-energy production through metabolic rewiring and mitochondrial dysfunction.
A mismatch between behavioral energy demands and reduced cellular-energy capacity may be a core mechanism of persistent fatigue in ME/CFS.
Circadian and sleep disturbances are likely mediators linking inflammation to fatigue, not merely consequences.
Multiple metabolic pathways (glucose metabolism, ROS, insulin signaling) converge to reduce available cellular energy in fatigue states.
Remaining Questions
Which specific inflammatory molecules or cytokines are most critical in driving the metabolic switch in ME/CFS patients?
What This Study Does Not Prove
This is a narrative review, not a primary experimental study, so it does not provide new empirical data proving the proposed mechanism in ME/CFS patients. The model describes correlation and proposed causality but does not establish that inflammation directly causes the metabolic switch or that preventing the switch would resolve fatigue. The review acknowledges limited mechanistic evidence specifically in cancer-related fatigue, leaving that connection uncertain.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
How do circadian disruptions and sleep loss mechanistically amplify the metabolic dysfunction, and can restoring sleep/circadian alignment partially reverse energy depletion?
Why do some individuals show increased effort expenditure despite energy depletion, and what neurobiological factors control this maladaptive drive?
Do interventions targeting mitochondrial function, metabolic switching, or sleep restoration improve fatigue in ME/CFS, and which metabolic changes correlate with symptom improvement?