Category: Pathophysiology

The Neuroinflammatory Etiopathology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating multi-systemic chronic illness of unknown etiology, classified as a neurological disorder by the World Health Organization (WHO). The symptomatology of the condition appears to emanate from a variety of sources of chronic neurological disturbance and associated distortions, and chronicity, in noxious sensory signaling and neuroimmune activation. This article incorporates a summary review and discussion of biomedical research considered relevant to this essential conception perspective. It is intended to provide stakeholders with a concise, integrated outline disease model in order to help demystify this major public health problem. The primary etiopathological factors presented are:

(A) Postural/biomechanical pain signaling, affecting adverse neuroexcitation, in the context of compression, constriction, strain, or damage of vertebral-regional bone and neuromuscular tissues;

(B) Immune mediated inflammatory sequelae, in the context of prolonged immunotropic neurotrophic infection-with lymphotropic/gliotropic/glio-toxic varieties implicated in particular;

(C) A combination of factors A and B. Sustained glial activation under such conditions is associated with oxidative and nitrosative stress, neuroinflammation, and neural sensitivity. These processes collectively enhance the potential for multi-systemic disarray involving endocrine pathway aberration, immune and mitochondrial dysfunction, and neurodegeneration, and tend toward still more intractable synergistic neuro-glial dysfunction (gliopathy), autoimmunity, and central neuronal sensitization.

 

Source: Glassford JA. The Neuroinflammatory Etiopathology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Front Physiol. 2017 Feb 17;8:88. doi: 10.3389/fphys.2017.00088. eCollection 2017. http://journal.frontiersin.org/article/10.3389/fphys.2017.00088/full (Full article)

 

Characteristic chemical signature for chronic fatigue syndrome identified

Chronic fatigue syndrome (CFS) is a mysterious and maddening condition, with no cure or known cause. But researchers at the University of California San Diego School of Medicine, using a variety of techniques to identify and assess targeted metabolites in blood plasma, have identified a characteristic chemical signature for the debilitating ailment and an unexpected underlying biology: It is similar to the state of dauer, and other hypometabolic syndromes like caloric restriction, diapause and hibernation.

Dauer is the German word for persistence or long-lived. It is a type of stasis in the development in some invertebrates that is prompted by harsh environmental conditions. The findings are published online in the August 29 issue of PNAS.

“CFS is a very challenging disease,” said first author Robert K. Naviaux, MD, PhD, professor of medicine, pediatrics and pathology and director of the Mitochondrial and Metabolic Disease Center at UC San Diego School of Medicine. “It affects multiple systems of the body. Symptoms vary and are common to many other diseases. There is no diagnostic laboratory test. Patients may spend tens of thousands of dollars and years trying to get a correct diagnosis.”

As many as 2.5 million Americans are believed to have CFS. It most often afflicts women in their 30s to 50s, though both genders and all ages can be affected. The primary symptom is severe fatigue lasting at least six months, with corollary symptoms ranging from muscle pain and headaches to sleep and memory problems.

Naviaux and colleagues studied 84 subjects: 45 men and women who met the diagnostic criteria for CFS and 39 matched controls. The researchers targeted 612 metabolites (substances produced by the processes of metabolism) from 63 biochemical pathways in blood plasma. They found that individuals with CFS showed abnormalities in 20 metabolic pathways. Eighty percent of the diagnostic metabolites measured were decreased, consistent with hypometabolic syndrome or reduced metabolism. The diagnostic accuracy rate exceeded 90 percent.

“Despite the heterogeneity of CFS, the diversity of factors that lead to this condition, our findings show that the cellular metabolic response is the same in patients,” said Naviaux. “And interestingly, it’s chemically similar to the dauer state you see in some organisms, which kicks in when environmental stresses trigger a slow-down in metabolism to permit survival under conditions that might otherwise cause cell death. In CFS, this slow-down comes at the cost of long-term pain and disability.”

Naviaux said the findings show that CFS possesses an objectively identifiable chemical signature in both men and women and that targeted metabolomics, which provide direct small molecule information, can provide actionable treatment information. Only 25 percent of the metabolite disturbances found in each person were needed for the diagnosis of CFS. Roughly 75 percent of abnormalities were unique to each individual, which Naviaux said is useful in guiding personalized treatment.

“This work opens a fresh path to both understanding the biology of CFS and, more importantly to patients, a robust, rational way to develop new therapeutics for a disease sorely in need of them.”

The study authors noted additional research using larger groups of participants from diverse geographical areas is needed to validate both the universality and specificity of the findings.

 

Journal Reference: Robert K. Naviaux, Jane C. Naviaux, Kefeng Li, A. Taylor Bright, William A. Alaynick, Lin Wang, Asha Baxter, Neil Nathan, Wayne Anderson, Eric Gordon. Metabolic features of chronic fatigue syndrome. Proceedings of the National Academy of Sciences, 2016; 201607571 DOI: 10.1073/pnas.1607571113

 

Source: University of California – San Diego. “Characteristic chemical signature for chronic fatigue syndrome identified: Discovery, along with revealed underlying biology, could lead to faster, more accurate diagnoses and more effective, personalized therapies.” ScienceDaily. ScienceDaily, 29 August 2016. https://www.sciencedaily.com/releases/2016/08/160829163253.htm

 

Chronic fatigue syndrome is in your gut, not your head

Physicians have been mystified by chronic fatigue syndrome, a condition where normal exertion leads to debilitating fatigue that isn’t alleviated by rest. There are no known triggers, and diagnosis requires lengthy tests administered by an expert.

Now, for the first time, Cornell University researchers report they have identified biological markers of the disease in gut bacteria and inflammatory microbial agents in the blood.

In a study published June 23 in the journal Microbiome, the team describes how they correctly diagnosed myalgic encephalomyeletis/chronic fatigue syndrome (ME/CFS) in 83 percent of patients through stool samples and blood work, offering a noninvasive diagnosis and a step toward understanding the cause of the disease.

“Our work demonstrates that the gut bacterial microbiome in chronic fatigue syndrome patients isn’t normal, perhaps leading to gastrointestinal and inflammatory symptoms in victims of the disease,” said Maureen Hanson, the Liberty Hyde Bailey Professor in the Department of Molecular Biology and Genetics at Cornell and the paper’s senior author. “Furthermore, our detection of a biological abnormality provides further evidence against the ridiculous concept that the disease is psychological in origin.”

“In the future, we could see this technique as a complement to other noninvasive diagnoses, but if we have a better idea of what is going on with these gut microbes and patients, maybe clinicians could consider changing diets, using prebiotics such as dietary fibers or probiotics to help treat the disease,” said Ludovic Giloteaux, a postdoctoral researcher and first author of the study.

In the study, Ithaca campus researchers collaborated with Dr. Susan Levine, an ME/CFS specialist in New York City, who recruited 48 people diagnosed with ME/CFS and 39 healthy controls to provide stool and blood samples.

The researchers sequenced regions of microbial DNA from the stool samples to identify different types of bacteria. Overall, the diversity of types of bacteria was greatly reduced and there were fewer bacterial species known to be anti-inflammatory in ME/CFS patients compared with healthy people, an observation also seen in people with Crohn’s disease and ulcerative colitis.

At the same time, the researchers discovered specific markers of inflammation in the blood, likely due to a leaky gut from intestinal problems that allow bacteria to enter the blood, Giloteaux said.

Bacteria in the blood will trigger an immune response, which could worsen symptoms.

The researchers have no evidence to distinguish whether the altered gut microbiome is a cause or a whether it is a consequence of disease, Giloteaux added.

In the future, the research team will look for evidence of viruses and fungi in the gut, to see whether one of these or an association of these along with bacteria may be causing or contributing to the illness.

 

Journal Reference: Ludovic Giloteaux, Julia K. Goodrich, William A. Walters, Susan M. Levine, Ruth E. Ley, Maureen R. Hanson. Reduced diversity and altered composition of the gut microbiome in individuals with myalgic encephalomyelitis/chronic fatigue syndrome. Microbiome, 2016; 4 (1) DOI: 10.1186/s40168-016-0171-4

 

Source: Cornell University. “Chronic fatigue syndrome is in your gut, not your head.” ScienceDaily. ScienceDaily, 27 June 2016. https://www.sciencedaily.com/releases/2016/06/160627160939.htm

 

Further clues in the fight against chronic fatigue syndrome

New findings regarding the pathology of Chronic Fatigue Syndrome (CFS) are bringing Griffith University researchers closer to identifying the cause of this disabling illness.

This is the news from a team at the National Centre for Neuroimmunology and Emerging Diseases at the Menzies Health Institute Queensland.

Professors Marshall-Gradisnik and Don Staines and their research team have identified significant impairments in cellular function of people with CFS.

CFS — sometimes known as ME (myalgic encephalomyelitis) — is a complex illness characterized by impaired memory and concentration, metabolic, cardiac, gut and immune dysfunction and debilitating muscle pain and fatigue on exertion (also known as neuroimmune exhaustion).

It is estimated that the prevalence rate of CFS/ME worldwide is between 1 and 2 per cent.

“While the patho-mechanism of CFS/ME is unknown, these recent findings by NCNED researchers provide further evidence for the pathology of this illness,” says Professor Sonya Marshall-Gradisnik, who speaks as we approach International CFS Awareness Day on Thursday May 12.

Published in the Journal of Translational Medicine, the results report significant differences in intracellular signalling of cells with CFS patients.

“In this group, we see that dysfunctional signalling may contribute to impaired cell activity. These findings are consistent with our previous findings and align with the presentation of symptoms in patients,” says Professor Staines.

The current research findings build upon recent discoveries including novel identification of key genetic changes in cells of the immune system.

The NCNED — internationally recognised for research into CFS/ME — will present a seminar on current research findings on this disease on International CFS/ME Awareness Day, Thursday May 12 at Griffith University, Gold Coast Campus, commencing 1pm, location G17, Lecture theatre 3.

Griffith University will also be illuminating the Griffith Health Centre in blue to further help raise awareness for CFS/ME.

Journal Reference: Teilah Kathryn Huth, Donald Staines, Sonya Marshall-Gradisnik. ERK1/2, MEK1/2 and p38 downstream signalling molecules impaired in CD56dimCD16 and CD56brightCD16dim/− natural killer cells in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis patients. Journal of Translational Medicine, 2016; 14 (1) DOI: 10.1186/s12967-016-0859-z

 

Source: Griffith University. “Further clues in the fight against chronic fatigue syndrome.” ScienceDaily. ScienceDaily, 10 May 2016. https://www.sciencedaily.com/releases/2016/05/160510093906.htm

 

New light shed on cause of chronic fatigue syndrome

New research findings may shed new light on the potential cause of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

Researchers from Griffith University’s National Centre for Neuroimmunology and Emerging Diseases (NCNED) — part of the new Menzies Health Institute Queensland — have uncovered significant factors contributing to the pathology of this illness.

The results reveal genetic changes in important receptors associated with immunological and cellular function and contribute to the development of this complex illness.

“These findings have been achieved through a team effort involving researchers, patients, funding bodies, clinicians and the support of Griffith University and the Queensland Government,” say chief investigators Professor Sonya Marshall-Gradisnik and Professor Donald Staines.

Co-researcher and consultant immunologist Professor Pete Smith said that important signalling mechanisms are disrupted as a result of these genetic changes involving the detection and response to threats.

“These are primitive genes that are involved in many cellular signals in the brain, gut, cardiovascular and immune systems, as well as in the mediation of pain.”

These research findings coincide with International Neuroimmune Awareness week commencing Monday 11 May.

The Griffith Health Centre on the university’s Gold Coast campus is being lit up each evening from 10 -12 May to raise awareness of neurological conditions such as CFS/ME as well as other conditions such as Fibromyalgia and Gulf War Syndrome.

“The lighting up of the Griffith Health Centre signifies Griffith’s commitment to the CFS patient community and our team approach to this research,” says Pro-Vice Chancellor (Health) Professor Allan Cripps.

CFS/ME is a highly debilitating disorder characterized by profound fatigue, muscle and joint pain, cerebral symptoms of impaired memory and concentration, impaired cardiovascular function, gut disorder and sensory dysfunction such as noise intolerance and balance disturbance. Many cases can continue for months or years. It is believed to affect around 250,000 Australians.

The research findings are to be presented at an international conference in London later this month.

Journal Reference: Sonya Marshall-Gradisnik, Donald Staines, Pete Smith, Bernd Nilius, Ekua Brenu, Sandra Ramos. Examination of Single Nucleotide Polymorphisms (SNPs) in Transient Receptor Potential (TRP) Ion Channels in Chronic Fatigue Syndrome Patients. Immunology and Immunogenetics Insights, 2015; 1 DOI: 10.4137/III.S25147

 

Source: Griffith University. “New light shed on cause of chronic fatigue syndrome.” ScienceDaily. ScienceDaily, 11 May 2015. https://www.sciencedaily.com/releases/2015/05/150511172755.htm 

 

Chronic fatigue syndrome patients had reduced activity in brain’s ‘reward center’

Chronic fatigue syndrome, a medical disorder characterized by extreme and ongoing fatigue with no other diagnosed cause, remains poorly understood despite decades of scientific study. Although researchers estimate that more than 1 million Americans are affected by this condition, the cause for chronic fatigue syndrome, a definitive way to diagnose it, and even its very existence remain in question. In a new study, researchers have found differing brain responses in people with this condition compared to healthy controls, suggesting an association between a biologic functional response and chronic fatigue syndrome.

The findings show that patients with chronic fatigue syndrome have decreased activation of an area of the brain known as the basal ganglia in response to reward. Additionally, the extent of this lowered activation was associated with each patient’s measured level of fatigue. The basal ganglia are at the base of the brain and are associated with a variety of functions, including motor activity and motivation. Diseases affecting basal ganglia are often associated with fatigue. These results shed more light on this mysterious condition, information that researchers hope may eventually lead to better treatments for chronic fatigue syndrome.

The study was conducted by Elizabeth R. Unger, James F. Jones, and Hao Tian of the Centers for Disease Control and Prevention (CDC), Andrew H. Miller and Daniel F. Drake of Emory University School of Medicine, and Giuseppe Pagnoni of the University of Modena and Reggio Emilia. An abstract of their study entitled, “Decreased Basal Ganglia Activation in Chronic Fatigue Syndrome Subjects is Associated with Increased Fatigue,” will be discussed at the meeting Experimental Biology 2012, being held April 21-25 at the San Diego Convention Center. The abstract is sponsored by the American Society for Investigative Pathology (ASIP), one of six scientific societies sponsoring the conference which last year attracted some 14,000 attendees.

More Fatigue, Less Activation

Dr. Unger says that she and her colleagues became curious about the role of the basal ganglia after previous studies by collaborators at Emory University showed that patients treated with interferon alpha, a common treatment for chronic hepatitis C and several other conditions, often experienced extreme fatigue. Further investigation into this phenomenon showed that basal ganglia activity decreased in patients who received this immune therapy. Since the fatigue induced by interferon alpha shares many characteristics with chronic fatigue syndrome, Unger and her colleagues decided to investigate whether the basal ganglia were also affected in this disorder.

The researchers recruited 18 patients with chronic fatigue syndrome, as well as 41 healthy volunteers with no symptoms of CFS. Each study participant underwent functional magnetic resonance imaging, a brain scan technique that measures activity in various parts of the brain by blood flow, while they played a simple card game meant to stimulate feelings of reward. The participants were each told that they’d win a small amount of money if they correctly guessed whether a preselected card was red or black. After making their choice, they were presented with the card while researchers measured blood flow to the basal ganglia during winning and losing hands.

The researchers showed that patients with chronic fatigue syndrome experienced significantly less change in basal ganglia blood flow between winning and losing than the healthy volunteers. When the researchers looked at scores for the Multidimensional Fatigue Inventory, a survey often used to document fatigue for chronic fatigue syndrome and various other conditions, they also found that the extent of a patient’s fatigue was tightly tied with the change in brain activity between winning and losing. Those with the most fatigue had the smallest change.

Results Suggest Role of Inflammation

Unger notes that the findings add to our understanding of biological factors that may play a role in chronic fatigue syndrome. “Many patients with chronic fatigue syndrome encounter a lot of skepticism about their illness,” she says. “They have difficulty getting their friends, colleagues, coworkers, and even some physicians to understand their illness. These results provide another clue into the biology of chronic fatigue syndrome.”

The study also suggests some areas of further research that could help scientists develop treatments for this condition in the future, she adds. Since the basal ganglia use the chemical dopamine as their major neurotransmitter, dopamine metabolism may play an important role in understanding and changing the course of this illness. Similarly, the difference in basal ganglia activation between the patients and healthy volunteers may be caused by inflammation, a factor now recognized as pivotal in a variety of conditions, ranging from heart disease to cancer.

Estimates from the CDC suggest that annual medical costs associated with chronic fatigue syndrome total about $14 billion in the United States. Annual losses to productivity because of lost work time range between $9 and $37 billion, with costs to individual households ranging between $8,000 and $20,000 per year.

 

Source: Federation of American Societies for Experimental Biology (FASEB). (2012, April 24). Chronic fatigue syndrome patients had reduced activity in brain’s ‘reward center’. ScienceDaily. Retrieved March 4, 2017 from https://www.sciencedaily.com/releases/2012/04/120424142109.htm

 

Epigenetic modifications and glucocorticoid sensitivity in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating idiopathic disease characterized by unexplained fatigue that fails to resolve with sufficient rest. Diagnosis is based on a list of symptoms and exclusion of other fatigue-related health conditions. Despite a heterogeneous patient population, immune and hypothalamic-pituitary-adrenal (HPA) axis function differences, such as enhanced negative feedback to glucocorticoids, are recurring findings in ME/CFS studies. Epigenetic modifications, such as CpG methylation, are known to regulate long-term phenotypic differences and previous work by our group found DNA methylome differences in ME/CFS, however the relationship between DNA methylome modifications, clinical and functional characteristics associated with ME/CFS has not been examined.

METHODS: We examined the DNA methylome in peripheral blood mononuclear cells (PBMCs) of a larger cohort of female ME/CFS patients using the Illumina HumanMethylation450 BeadChip Array. In parallel to the DNA methylome analysis, we investigated in vitro glucocorticoid sensitivity differences by stimulating PBMCs with phytohaemagglutinin and suppressed growth with dexamethasone. We explored DNA methylation differences using bisulfite pyrosequencing and statistical permutation. Linear regression was implemented to discover epigenomic regions associated with self-reported quality of life and network analysis of gene ontology terms to biologically contextualize results.

RESULTS: We detected 12,608 differentially methylated sites between ME/CFS patients and healthy controls predominantly localized to cellular metabolism genes, some of which were also related to self-reported quality of life health scores. Among ME/CFS patients, glucocorticoid sensitivity was associated with differential methylation at 13 loci.

CONCLUSIONS: Our results indicate DNA methylation modifications in cellular metabolism in ME/CFS despite a heterogeneous patient population, implicating these processes in immune and HPA axis dysfunction in ME/CFS. Modifications to epigenetic loci associated with differences in glucocorticoid sensitivity may be important as biomarkers for future clinical testing. Overall, these findings align with recent ME/CFS work that point towards impairment in cellular energy production in this patient population.

 

Source: de Vega WC, Herrera S, Vernon SD, McGowan PO. Epigenetic modifications and glucocorticoid sensitivity in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). BMC Med Genomics. 2017 Feb 23;10(1):11. doi: 10.1186/s12920-017-0248-3. https://www.ncbi.nlm.nih.gov/pubmed/28231836

 

Mechanisms Explaining Muscle Fatigue and Muscle Pain in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a Review of Recent Findings

Abstract:

PURPOSE OF REVIEW: Here, we review potential causes of muscle dysfunction seen in many patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) such as the effects of oxidative and nitrosative stress (O&NS) and mitochondrial impairments together with reduced heat shock protein production and a range of metabolic abnormalities.

RECENT FINDINGS: Several studies published in the last few years have highlighted the existence of chronic O&NS, inflammation, impaired mitochondrial function and reduced heat shock protein production in many patients with ME/CFS. These studies have also highlighted the detrimental effects of chronically elevated O&NS on muscle functions such as reducing the time to muscle fatigue during exercise and impairing muscle contractility.

Mechanisms have also been revealed by which chronic O&NS and or impaired heat shock production may impair muscle repair following exercise and indeed the adaptive responses in the striated muscle to acute and chronic increases in physical activity. The presence of chronic O&NS, low-grade inflammation and impaired heat shock protein production may well explain the objective findings of increased muscle fatigue, impaired contractility and multiple dimensions of exercise intolerance in many patients with ME/CFS.

 

Source: Gerwyn M, Maes M. Mechanisms Explaining Muscle Fatigue and Muscle Pain in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a Review of Recent Findings. Curr Rheumatol Rep. 2017 Jan;19(1):1. doi: 10.1007/s11926-017-0628-x. https://www.ncbi.nlm.nih.gov/pubmed/28116577

 

Metabolic profiling of a myalgic encephalomyelitis/chronic fatigue syndrome discovery cohort reveals disturbances in fatty acid and lipid metabolism

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) remains a continuum spectrum disease without biomarkers or simple objective tests, and therefore relies on a diagnosis from a set of symptoms to link the assortment of brain and body disorders to ME/CFS. Although recent studies show various affected pathways, the underlying basis of ME/CFS has yet to be established.

In this pilot study, we compare plasma metabolic signatures in a discovery cohort, 17 patients and 15 matched controls, and explore potential metabolic perturbations as the aftermath of the complex interactions between genes, transcripts and proteins.

This approach to examine the complex array of symptoms and underlying foundation of ME/CFS revealed 74 differentially accumulating metabolites, out of 361 (P < 0.05), and 35 significantly altered after statistical correction (Q < 0.15). The latter list includes several essential energy-related compounds which could theoretically be linked to the general lack of energy observed in ME/CFS patients. Pathway analysis points to a few pathways with high impact and therefore potential disturbances in patients, mainly taurine metabolism and glycerophospholipid metabolism, combined with primary bile acid metabolism, as well as glyoxylate and dicarboxylate metabolism and a few other pathways, all involved broadly in fatty acid metabolism.

Purines, including ADP and ATP, pyrimidines and several amino acid metabolic pathways were found to be significantly disturbed. Finally, glucose and oxaloacetate were two main metabolites affected that have a major effect on sugar and energy levels. Our work provides a prospective path for diagnosis and understanding of the underlying mechanisms of ME/CFS.

 

Source: Germain A, Ruppert D, Levine SM, Hanson MR. Metabolic profiling of a myalgic encephalomyelitis/chronic fatigue syndrome discovery cohort reveals disturbances in fatty acid and lipid metabolism. Mol Biosyst. 2017 Jan 31;13(2):371-379. doi: 10.1039/c6mb00600k. https://www.ncbi.nlm.nih.gov/pubmed/28059425

 

Metabolic profiling indicates impaired pyruvate dehydrogenase function in myalgic encephalopathy/chronic fatigue syndrome

Abstract:

Myalgic encephalopathy/chronic fatigue syndrome (ME/CFS) is a debilitating disease of unknown etiology, with hallmark symptoms including postexertional malaise and poor recovery. Metabolic dysfunction is a plausible contributing factor.

We hypothesized that changes in serum amino acids may disclose specific defects in energy metabolism in ME/CFS. Analysis in 200 ME/CFS patients and 102 healthy individuals showed a specific reduction of amino acids that fuel oxidative metabolism via the TCA cycle, mainly in female ME/CFS patients. Serum 3-methylhistidine, a marker of endogenous protein catabolism, was significantly increased in male patients.

The amino acid pattern suggested functional impairment of pyruvate dehydrogenase (PDH), supported by increased mRNA expression of the inhibitory PDH kinases 1, 2, and 4; sirtuin 4; and PPARδ in peripheral blood mononuclear cells from both sexes. Myoblasts grown in presence of serum from patients with severe ME/CFS showed metabolic adaptations, including increased mitochondrial respiration and excessive lactate secretion. The amino acid changes could not be explained by symptom severity, disease duration, age, BMI, or physical activity level among patients.

These findings are in agreement with the clinical disease presentation of ME/CFS, with inadequate ATP generation by oxidative phosphorylation and excessive lactate generation upon exertion.

 

Source: Fluge Ø, Mella O, Bruland O, Risa K, Dyrstad SE, Alme K, Rekeland IG, Sapkota D, Røsland GV, Fosså A, Ktoridou-Valen I, Lunde S, Sørland K, Lien K, Herder I, Thürmer H, Gotaas ME, Baranowska KA, Bohnen LM, Schäfer C, McCann A, Sommerfelt K, Helgeland L, Ueland PM, Dahl O, Tronstad KJ. Metabolic profiling indicates impaired pyruvate dehydrogenase function in myalgic encephalopathy/chronic fatigue syndrome. JCI Insight. 2016 Dec 22;1(21):e89376. doi: 10.1172/jci.insight.89376. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5161229/ (Full article)