Skeletal muscle wastage in Crohn's disease: a pathway shared with heart failure?
BACKGROUND
Lean body mass wastage in active Crohn's disease is not only related to malnutrition, but also to local and systemic inflammation. Altered bowel permeability can represent a source of pro-inflammatory cytokines, that have been shown to produce muscle wastage by several mechanisms such as apoptosis. In our study we have evaluated the body composition and the pathological changes of skeletal muscle in patients with Crohn's disease to see whether a relationships between altered gut permeability, proinflammatory cytokines production and muscle wastage existed.


METHODS
Thirteen consecutive steroid-free patients with active Crohn's disease underwent evaluation of body composition, sugar test for intestinal permeability, determination of serum levels of TNF-alpha, sphingosine, bacterial lipopolysaccaride, and biopsy of gastrocnemius. In bioptic samples we determined fibres cross sectional area, distribution of myosin heavy chains and apoptosis. Twenty healthy subjects formed the control group.


RESULTS
In patients lean body mass was reduced and intestinal permeability increased (p<0.01 for both). TNFalpha, sphingosine and lipopolysaccaride were increased (p<0.01). Fibres size was reduced (p<0.01), with shift of Myosin Heavy Chains from the slow to the fast type. Apoptosis was found in 5 patients' biopsies, never in controls.


CONCLUSIONS
Crohn's patients have a myopathy characterized by myocyte apoptosis, modifications of myosin and muscle atrophy. TNF-alpha and sphingosine, that are increased because of the enhanced lipopolysaccaride concentration due to altered gut permeability, may play a pathophysiological role in the development of this myopathy.
Cuoco
Lucio
L
Gastroenterology and Internal Medicine Unit, S. Bortolo Hospital, Vicenza, Italy.
Vescovo
Giorgio
G
Castaman
Roberto
R
Ravara
Barbara
B
Cammarota
Giovanni
G
Angelini
Annalisa
A
Salvagnini
Mario
M
Dalla Libera
Luciano
L
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D017209:Apoptosis; D001706:Biopsy; D001823:Body Composition; D016022:Case-Control Studies; D003424:Crohn Disease / Q000097:blood / Q000473:pathology* / Q000503:physiopathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D020287:In Situ Nick-End Labeling; D007408:Intestinal Absorption / Q000502:physiology; D016014:Linear Models; D008070:Lipopolysaccharides / Q000097:blood; D008297:Male; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology*; D009133:Muscular Atrophy; D018995:Myosin Heavy Chains / Q000032:analysis; D009752:Nutritional Status; D013110:Sphingosine / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D015854:Up-Regulation
D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D018995:Myosin Heavy Chains; D013110:Sphingosine