BACKGROUND: The gut is a major energy consumer, but a comprehensive overview of the adaptive response to @entity4053 is lacking. Gene-expression profiling, pathway analysis, and immunohistochemistry were therefore carried out on @entity19 small intestine after 0, 12, 24, and 72 hours of @entity4053 . RESULTS: Intestinal weight declined to 50% of control, but this loss of tissue mass was distributed proportionally among the gut's structural components, so that the microarrays' tissue base remained unaffected. Unsupervised hierarchical clustering of the microarrays revealed that the successive time points separated into distinct branches. Pathway analysis depicted a pronounced, but transient early response that peaked at 12 hours, and a late response that became progressively more pronounced with continued @entity4053 . Early changes in gene expression were compatible with a cellular deficiency in @entity1160 , and metabolic adaptations directed at @entity1160 conservation, inhibition of @entity2388 oxidation, stimulation of @entity2227 catabolism via @entity492 and @entity7954 to @entity880 , and enhanced @entity844 oxidation and @entity6178 -body synthesis. In addition, the expression of key genes involved in cell cycling and apoptosis was suppressed. At 24 hours of @entity4053 , many of the early adaptive changes abated. Major changes upon continued @entity4053 implied the production of @entity413 rather than @entity880 from @entity1735 backbones, a downregulation of @entity844 oxidation and a very strong downregulation of the electron-transport chain. Cell cycling and apoptosis remained suppressed. CONCLUSION: The changes in gene expression indicate that the small intestine rapidly looses mass during @entity4053 to generate @entity880 or @entity413 and @entity6178 bodies. Meanwhile, intestinal architecture is maintained by downregulation of cell turnover.

Fasting induces a biphasic adaptive metabolic response in XXXX small intestine.

@entity844 :: ('CHEBI:35366', 'Chemical') :: ['fatty-acid'] @entity2227 :: ('CHEBI:29987', 'Chemical') :: ['glutamate'] @entity1160 :: ('CHEBI:28300', 'Chemical') :: ['glutamine'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity7954 :: ('MESH:D010728', 'Chemical') :: ['phosphoenolpyruvate'] @entity1735 :: ('CHEBI:16646', 'Chemical') :: ['carbohydrate'] @entity4053 :: ('MESH:D007003', 'Disease') :: ['fasting'] @entity492 :: ('CHEBI:29995', 'Chemical') :: ['aspartate'] @entity880 :: ('MESH:D019344', 'Chemical') :: ['lactate'] @entity6178 :: ('CHEBI:17087', 'Chemical') :: ['ketone'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose'] @entity2388 :: ('MESH:D019289', 'Chemical') :: ['pyruvate']
@entity19 :: (10090,Species) :: ['murine']
