Modification of the functional capacity of sarcoplasmic reticulum membranes in patients suffering from chronic fatigue syndrome

Laboratorio Interuniversitario di Miologia, Università 'G. d'Annunzio', Nuovo Polo Didattico, 66013 Chieti Scalo, Italy.
Neuromuscular Disorders (Impact Factor: 2.64). 09/2003; 13(6):479-84. DOI: 10.1016/S0960-8966(03)00042-7
Source: PubMed


In chronic fatigue syndrome, several reported alterations may be related to specific oxidative modifications in muscle. Since sarcoplasmic reticulum membranes are the basic structures involved in excitation-contraction coupling and the thiol groups of Ca(2+) channels of SR terminal cisternae are specific targets for reactive oxygen species, it is possible that excitation-contraction coupling is involved in this pathology. We investigated the possibility that abnormalities in this compartment are involved in the pathogenesis of chronic fatigue syndrome and consequently responsible for characteristic fatigue. The data presented here support this hypothesis and indicate that the sarcolemmal conduction system and some aspects of Ca(2+) transport are negatively influenced in chronic fatigue syndrome. In fact, both deregulation of pump activities (Na(+)/K(+) and Ca(2+)-ATPase) and alteration in the opening status of ryanodine channels may result from increased membrane fluidity involving sarcoplasmic reticulum membranes.

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Available from: Stefania Fulle
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    • "This binding assay was performed with membranes purified from the wild-type and MLC/mIGF-1 mature myotubes sonicated in sodium phosphate buffer (20 mM NaPO4, pH 7.0) supplemented with protease inhibitors according to a procedure described by Fulle et al. [22]. The dihydropyridine receptor (DHPR) concentrations were determined using the radioligand [3H]-PN200-110. "
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    • "Increased activity of Na + /K + -ATPase has been reported in several other pathological conditions such as in experimentally induced epilepsy (Fernandes et al., 1996; Reime et al., 2007), and in Crush syndrome (Desai and Desai, 2007). In chronic fatigue syndrome, the activities of both Na + / K + -ATPase and Ca 2+ /Mg 2+ -ATPase are increased in sarcoplasmic reticulum membranes (Fulle et al., 2003). In addition, Takser et al. (2003) reported a correlation of ATPase activities with early psychomotor development in humans. "
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