Tag: ADP

Mapping the Complexity of ME/CFS: Evidence for Abnormal Energy Metabolism, Altered Immune Profile and Vascular Dysfunction

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disorder with no known underlying mechanisms, diagnostic tools, or treatments.  Multiple areas of dysfunction have been extensively studied, but rarely examined together. We recruited age- and sex-matched ME/CFS patients and healthy controls for a multi-modal study examining energy metabolism, immune profiles and plasma protein levels.

Elevated levels of adenosine monophosphate (AMP) were detected in both plasma and immune cells. Additionally, immune cells showed higher levels of adenosine diphosphate (ADP) and a reduced adenosine triphosphate/adenosine diphosphate (ATP/ADP) ratio.

These findings imply decreased ATP generation and the presence of energy stress within the immune cell population. Adaptive immune cell populations were skewed towards less mature effector subsets of CD4+, CD8+ and gd T cells, and proportions of CD1c+CD141-conventional DC type 2 (cDC2) and CD56lowCD16+ terminal natural killer (NK) cells were also reduced. Elevated levels of plasma proteins associated with thrombus formation and vascular reactivity may contribute to the endothelial dysfunction observed in ME/CFS patients. Using Classification and Regression Tree (CART) modelling, we identified variables from each mode of investigation with strong predictive potential for ME/CFS. Together, this study provides new insights into the somatic symptoms and underlying biology of ME/CFS.

Source: Heng, Ruiwen Benjamin and Gunasegaran, Bavani and Krishnamurthy, Shivani and Bustamante, Sonia and Staats, Ananda and Chow, Sharron and Ahn, Seong Beom and Paul-Heng, Moumita and Maciver, Yolande and Smith, Kirsten and Tran, Denise Phuong and Howley, Peter P. and Bilgin, Ayse Aysin and Sharland, Alexandra and Schloeffel, Richard and Guillemin, Gilles J. and Administrator, Sneak Peek, Mapping the Complexity of ME/CFS: Evidence for Abnormal Energy Metabolism, Altered Immune Profile and Vascular Dysfunction. Available at SSRN: https://ssrn.com/abstract=5131664 or http://dx.doi.org/10.2139/ssrn.5131664  https://papers.ssrn.com/sol3/papers.cfm?abstract_id=5131664 (Full text available as PDF file)

Reduced oxidative muscle metabolism in chronic fatigue syndrome

Abstract:

The purpose of this study was to determine if chronic fatigue syndrome (CSF) is characterized by abnormalities in oxidative muscle metabolism. Patients with CFS according to Centers for Disease Control (CDC) criteria (n = 22) were compared to normal sedentary subjects (n = 15).

CFS patients were also tested before and 2 days after a maximal treadmill test. Muscle oxidative capacity was measured as the maximal rate of postexercise phosphocreatine (PCr) resynthesis using the ADP model (Vmax) in the calf muscles using 31P magnetic resonance spectroscopy. Vmax was significantly reduced in CFS patients (39.6 +/- 2.8 mmol/L/min, mean +/- SE) compared to controls (53.8 +/- 2.8 mmol/L/min). Two days postexercise there was no change in resting inorganic phosphate (Pi)/PCr or Vmax in the CFS patients (n = 14).

In conclusion, oxidative metabolism is reduced in CFS patients compared to sedentary controls. In addition, a single bout of strenuous exercise did not cause a further reduction in oxidative metabolism, or alter resting Pi/PCr ratios.

Comment in: Chronic fatigue syndrome and skeletal muscle mitochondrial function. [Muscle Nerve. 1997]

 

Source: McCully KK, Natelson BH, Iotti S, Sisto S, Leigh JS Jr. Reduced oxidative muscle metabolism in chronic fatigue syndrome. Muscle Nerve. 1996 May;19(5):621-5. http://www.ncbi.nlm.nih.gov/pubmed/8618560