Category: Pathophysiology

Elevated levels of protein carbonyls in sera of chronic fatigue syndrome patients

Abstract:

Protein carbonyl levels, a measure of protein oxidation, were found to be significantly elevated (p < 0.0005) in the sera of chronic fatigue syndrome (CFS) patients vs. controls. In contrast, the total protein levels in sera CFS patients were unchanged from those of controls. The elevated protein carbonyl levels confirm earlier reports suggesting that oxidative stress is associated with chronic fatigue syndrome and are consistent with a prediction of the elevated nitric oxide/peroxynitrite theory of chronic fatigue syndrome and related conditions.

 

Source: Smirnova IV, Pall ML. Elevated levels of protein carbonyls in sera of chronic fatigue syndrome patients. Mol Cell Biochem. 2003 Jun;248(1-2):93-5. http://www.ncbi.nlm.nih.gov/pubmed/12870659

 

Hypothalamic digoxin, cerebral chemical dominance and myalgic encephalomyelitis

Abstract:

The isoprenoid pathway was assessed in 15 patients with chronic fatigue syndrome. The pathway was also assessed in individuals with differing hemispheric dominance to assess whether hemispheric dominance had any correlation with these disease states.

The isoprenoid metabolites–digoxin, dolichol, and ubiquinone–RBC membrane Na+-K+ ATPase activity, serum magnesium and tyrosine/tryptophan catabolic patterns were assessed. The free-radical metabolism, glycoconjugate metabolism, and RBC membrane composition was also assessed. Membrane Na+-K+ ATPase activity and serum magnesium levels were decreased while HMG CoA reductase activity and serum digoxin levels were increased in myalgic encephalomyelitis (ME). There were increased levels of tryptophan catabolites–nicotine, strychnine, quinolinic acid, and serotonin–and decreased levels of tyrosine catabolites–dopamine, noradrenaline, and morphine in ME. There was an increase in dolichol levels, carbohydrate residues of glycoproteins, glycolipids, total/individual GAG fractions, and lysosomal enzymes in ME. Reduced levels of ubiquinone, reduced glutathione, and free-radical scavenging enzymes, as well as increased lipid peroxidation products and nitric oxide, were noticed in ME.

The biochemical patterns in ME correlated with those obtained in right hemispheric chemical dominance. The role of hypothalamic digoxin and neurotransmitter induced immune activation, altered glycoconjugate metabolism, and resultant defective viral antigen presentation, NMDA excitotoxicity and cognitive dysfunction, and mitochondrial dysfunction related myalgia in the pathogenesis of ME is stressed. ME occurs in individuals with right hemispheric chemical dominance.

 

Source: Kurup RK, Kurup PA. Hypothalamic digoxin, cerebral chemical dominance and myalgic encephalomyelitis. Int J Neurosci. 2003 May;113(5):683-701. https://ammes.orgwp-admin/post-new.php

 

Cerebral and systemic hemodynamics changes during upright tilt in chronic fatigue syndrome

Abstract:

BACKGROUND AND PURPOSE: During head-up tilt (HUT), patients with chronic fatigue syndrome (CFS) have higher rates of neurally mediated hypotension (NMH) and postural tachycardia syndrome (POTS) than healthy controls. The authors studied whether patients with CFS were also more likely to have abnormal cerebral blood flow velocity (CBFV) compared with controls in response to orthostatic stress.

METHODS: Transcranial Doppler monitoring of middle cerebral artery (MCA) CBFV was performed during 3-stage HUT prospectively in 26 patients with CFS and 23 healthy controls. At the same time, continuous monitoring of arterial blood pressure (BP), heart rate (HR), endtidal CO2 (ET-CO2) were performed. Results are reported as mean +/- SD.

RESULTS: NMH developed in 21 patients with CFS and in 14 controls (P = .22). POTS was present in 9 CFS patients and 7 controls (P = .76). Supine HR was higher in CFS patients, but all other hemodynamics and CBFV measures were similar at baseline. The median time to hypotension did not differ, but the median time to onset of orthostatic symptoms was shorter in those with CFS (P < .001). The CBFV did not differ between groups in the supine posture, at 1 or 5 minutes after upright tilt, at 5 or 1 minute before the end of the test, or at termination of the test. Mean CBFV fell at termination of tilt testing in those with CFS and controls. ET-CO2 was lower at termination of the test in those with CFS versus controls (P = .002).

CONCLUSIONS: The results of this study are not consistent with the hypothesis that patients with CFS have a distinctive pattern of MCA CBFV changes in response to orthostatic stress.

 

Source: Razumovsky AY, DeBusk K, Calkins H, Snader S, Lucas KE, Vyas P, Hanley DF, Rowe PC. Cerebral and systemic hemodynamics changes during upright tilt in chronic fatigue syndrome. J Neuroimaging. 2003 Jan;13(1):57-67. http://www.ncbi.nlm.nih.gov/pubmed/12593133

 

Blood flow and muscle metabolism in chronic fatigue syndrome

Abstract:

The purpose of this study was to determine if chronic fatigue syndrome (CFS) is associated with reduced blood flow and oxidative delivery to skeletal muscle. Patients with CFS according to CDC (Center for Disease Control) criteria ( n =19) were compared with normal sedentary subjects ( n =11). Muscle blood flow was measured with Doppler ultrasound after cuff ischaemia and exercise. Muscle oxygen delivery was measured as the rate of post-exercise and post-ischaemic oxygen-haem resaturation. Oxygen-haem resaturation was measured in the medial gastrocnemius muscle using continuous wavelength near-IR spectroscopy. Muscle metabolism was measured using (31)P magnetic resonance spectroscopy. CFS patients and controls were not different in the peak blood flow after cuff ischaemia, the rate of recovery of phosphocreatine after submaximal exercise, and the rate of recovery of oxygen saturation after cuff ischaemia. In conclusion, CFS patients showed no deficit in blood flow or oxidative metabolism. This suggests that CFS symptoms do not require abnormal peripheral function.

 

Source: McCully KK, Smith S, Rajaei S, Leigh JS Jr, Natelson BH. Blood flow and muscle metabolism in chronic fatigue syndrome.  Clin Sci (Lond). 2003 Jun;104(6):641-7. http://www.ncbi.nlm.nih.gov/pubmed/12589704

 

Relationship between musculoskeletal symptoms and blood markers of oxidative stress in patients with chronic fatigue syndrome

Abstract:

In 21 patients with chronic fatigue syndrome (CFS) versus 20 normal subjects, we investigated the oxidant/antioxidant balance and its correlation with muscle symptoms. Patients versus controls showed significantly: lower Lag Phase and Vitamin E (Vit E) concentrations in plasma and low-density lipoproteins (LDL), higher LDL thiobarbituric acid reactive substances (TBARS), higher fatigue and lower muscle pain thresholds to electrical stimulation.

A significant direct linear correlation was found between fatigue and TBARS, thresholds and Lag Phase, thresholds and Vit E in plasma and LDL. A significant inverse linear correlation was found between fatigue and Lag Phase, fatigue and Vit E, thresholds and TBARS. Increased oxidative stress and decreased antioxidant defenses are related to the extent of symptomatology in CFS, suggesting that antioxidant supplementation might relieve muscle symptoms in the syndrome.

 

Source: Vecchiet J, Cipollone F, Falasca K, Mezzetti A, Pizzigallo E, Bucciarelli T, De Laurentis S, Affaitati G, De Cesare D, Giamberardino MA. Relationship between musculoskeletal symptoms and blood markers of oxidative stress in patients with chronic fatigue syndrome. Neurosci Lett. 2003 Jan 2;335(3):151-4. http://www.ncbi.nlm.nih.gov/pubmed/12531455

 

Chronic fatigue syndrome: what role does the autonomic nervous system play in the pathophysiology of this complex illness?

Abstract:

Chronic fatigue syndrome (CFS) is a serious health concern affecting over 800000 Americans of all ages, races and socioeconomic groups and both genders. The etiology and pathophysiology of CFS are unknown, yet studies have suggested an involvement of the autonomic nervous system (ANS). A symposium was organized in December 2000 to explore the possibility of an association between ANS dysfunction and CFS, with special emphasis on the interactions between ANS dysfunction and other abnormalities noted in the immune and endocrine systems of individuals with CFS. This paper represents the consensus of the panel of experts who participated in this meeting.

Copyright 2002 S. Karger AG, Basel

 

Source: Gerrity TR, Bates J, Bell DS, Chrousos G, Furst G, Hedrick T, Hurwitz B, Kula RW, Levine SM, Moore RC, Schondorf R. Chronic fatigue syndrome: what role does the autonomic nervous system play in the pathophysiology of this complex illness? Neuroimmunomodulation. 2002-2003;10(3):134-41. http://www.ncbi.nlm.nih.gov/pubmed/12481153

 

Chronic fatigue syndrome: a risk factor for osteopenia?

Abstract:

No data documenting a possible depletion of bone mineral density in patients with chronic fatigue syndrome (CFS) are currently available. However, recent pathophysiological observations in CFS patients may have deleterious consequences on bone density.

Firstly, the deregulation of the 2,5A synthetase RNase L antiviral pathway and its associated channelopathy, implicates increased demands for calcium and consequent increased calcium-re-absorption from the skeletal system.

Secondly, Mycoplasma fermentans which has been frequently associated with CFS, produces a lipopeptide, named 2-kDa macrophage-activating lipopeptide (MALP-2), which stimulates macrophages. MALP-2 has been shown to enhance bone resorption in a dose-dependent manner, at least in part by stimulating the formation of prostaglandins.

Thirdly, decreased levels of insulin-like growth factor I (IGF-I) have been reported in CFS-patients. IGF-I is critical to the proliferation of osteoblasts. Consequently, depleted levels of IGF-I may shift the balance between osteoclastic and osteoblastic activity towards bone resorption.

 

Source: Nijs J, De Meirleir K, Englebienne P, McGregor N. Chronic fatigue syndrome: a risk factor for osteopenia? Med Hypotheses. 2003 Jan;60(1):65-8. http://www.ncbi.nlm.nih.gov/pubmed/12450768

 

High prevalence of Mycoplasma infections among European chronic fatigue syndrome patients. Examination of four Mycoplasma species in blood of chronic fatigue syndrome patients

Abstract:

Prevalence of Mycoplasma species infections in chronic fatigue syndrome (CFS) has been extensively reported in the scientific literature. However, all previous reports highlighted the presence of Mycoplasmas in American patients. In this prospective study, the presence of Mycoplasma fermentans, M. penetrans, M. pneumoniae and M. hominis in the blood of 261 European CFS patients and 36 healthy volunteers was examined using forensic polymerase chain reaction.

One hundred and seventy-nine (68.6%) patients were infected by at least one species of Mycoplasma, compared to two out of 36 (5.6%) in the control sample (P<0.001). Among Mycoplasma-infected patients, M. hominis was the most frequently observed infection (n=96; 36.8% of the overall sample), followed by M. pneumoniae and M. fermentans infections (equal frequencies; n=67; 25.7%). M. penetrans infections were not found. Multiple mycoplasmal infections were detected in 45 patients (17.2%). Compared to American CFS patients (M. pneumoniae>M. hominis>M. penetrans), a slightly different pattern of mycoplasmal infections was found in European CFS patients (M. hominis>M. pneumoniae, M. fermentansz.Gt;M. penetrans).

 

Source: Nijs J, Nicolson GL, De Becker P, Coomans D, De Meirleir K. High prevalence of Mycoplasma infections among European chronic fatigue syndrome patients. Examination of four Mycoplasma species in blood of chronic fatigue syndrome patients. FEMS Immunol Med Microbiol. 2002 Nov 15;34(3):209-14. http://femsim.oxfordjournals.org/content/34/3/209.long (Full article)

 

Brain regions involved in fatigue sensation: reduced acetylcarnitine uptake into the brain

Abstract:

Fatigue is an indispensable sense for ordering rest. However, the neuronal and molecular mechanisms of fatigue remain unclear. Chronic fatigue syndrome (CFS) with long-lasting fatigue sensation seems to be a good model for studying these mechanisms underlying fatigue sensation.

Recently, we found that most patients with CFS showed a low level of serum acetylcarnitine, which well correlated with the rating score of fatigue, and that a considerable amount of acetyl moiety of serum acetylcarnitine is taken up into the brain. Here we show by metabolite analysis of the mouse brain that an acetyl moiety taken up into the brain through acetylcarnitine is mainly utilized for the biosynthesis of glutamate.

When we studied the cerebral uptake of acetylcarnitine by using [2-(11)C]acetyl-L-carnitine in 8 patients with CFS and in 8 normal age- and sex-matched controls, a significant decrease was found in several regions of the brains of the patient group, namely, in the prefrontal (Brodmann’s area 9/46d) and temporal (BA21 and 41) cortices, anterior cingulate (BA24 and 33), and cerebellum.

These findings suggest that the levels of biosynthesis of neurotransmitters through acetylcarnitine might be reduced in some brain regions of chronic fatigue patients and that this abnormality might be one of the keys to unveiling the mechanisms of the chronic fatigue sensation.

 

Source: Kuratsune H, Yamaguti K, Lindh G, Evengård B, Hagberg G, Matsumura K, Iwase M, Onoe H, Takahashi M, Machii T, Kanakura Y, Kitani T, Långström B, Watanabe Y. Brain regions involved in fatigue sensation: reduced acetylcarnitine uptake into the brain. Neuroimage. 2002 Nov;17(3):1256-65. http://www.ncbi.nlm.nih.gov/pubmed/12414265

 

Chronic fatigue syndrome: neurological findings may be related to blood–brain barrier permeability

Abstract:

Despite volumes of international research, the etiology of chronic fatigue syndrome (CFS) remains elusive. There is, however, considerable evidence that CFS is a disorder involving the central nervous system (CNS).

It is our hypothesis that altered permeability of the blood-brain barrier (BBB) may contribute to ongoing signs and symptoms found in CFS. To support this hypothesis we have examined agents that can increase the blood-brain barrier permeability (BBBP) and those that may be involved in CFS.

The factors which can compromise the normal BBBP in CFS include viruses, cytokines, 5-hydroxytryptamine, peroxynitrite, nitric oxide, stress, glutathione depletion, essential fatty acid deficiency, and N-methyl-D-aspartate overactivity. It is possible that breakdown of normal BBBP leads to CNS cellular dysfunction and disruptions of neuronal transmission in CFS. Abnormal changes in BBBP have been linked to a number of disorders involving the CNS; based on review of the literature we conclude that the BBB integrity in CFS warrants investigation.

Copyright 2001 Harcourt Publishers Ltd.

 

Source: Bested AC, Saunders PR, Logan AC. Chronic fatigue syndrome: neurological findings may be related to blood–brain barrier permeability. Med Hypotheses. 2001 Aug;57(2):231-7. http://www.ncbi.nlm.nih.gov/pubmed/11461179