A 65-year old patient has colon carcinoma metastatic to the liver and lungs. He has weight loss of 10 kg. Cytokine-dependent cachexia is attributable to which of the following
A. Increased glucose uptake and increased glycogen breakdown occursB. Suppressed activity of lipoprotein lipase from TNFα
C. TNFα stimulates lipolysis
D. The differentiation process of pre-adipocyte is impaired
E. none is true
The Answer
Is.: A. Increased glucose uptake and increased glycogen breakdown occurs, B.
Suppressed activity of lipoprotein lipase from TNFα , C. TNFa stimulates
lipolysis , D. The differentiation process of pre-adipocyte is impaired
Tumor cachexia appears to be mediated via TNFα.
Lipopolysaccharide (LPS), as well as other cytokines,
activate a variety of inflammatory cells, importantly macrophages, to produce
TNFα.
In vitro, higher TNFα concentrations alter glucose
metabolism by increasing glucose uptake and glycogen breakdown and also impairs
the Lipogenesis pathway
All of these metabolic effects somewhat explain the
chronic syndromes of anorexia, weight loss and cachexia that are associated
with chronic infection and malignancy.
