Glucose alleviates ammonia-induced inhibition of short-chain fatty acid metabolism in rat colonic epithelial cells
| Autor: | Mark Fitch, Sharon E. Fleming, John D. Cremin |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Male
medicine.medical_specialty Colon Physiology Citric Acid Cycle Ketone Bodies Butyrate Acetates Biology Ammonium Chloride chemistry.chemical_compound Ammonia Physiology (medical) Internal medicine medicine Animals Coenzyme A Intestinal Mucosa Diuretics chemistry.chemical_classification 3-Hydroxybutyric Acid Hepatology Gastroenterology Tricarboxylic Acids Fatty acid Epithelial Cells Metabolism Tricarboxylic acid Carbon Dioxide Fatty Acids Volatile Rats Inbred F344 Rats Glutamine Citric acid cycle Butyrates Glucose Endocrinology chemistry Biochemistry Ketone bodies Ammonium chloride Propionates Energy Metabolism Oxidation-Reduction |
| Zdroj: | American Journal of Physiology-Gastrointestinal and Liver Physiology. 285:G105-G114 |
| ISSN: | 1522-1547 0193-1857 |
| DOI: | 10.1152/ajpgi.00437.2002 |
| Popis: | Ammonia decreased metabolism by rat colonic epithelial cells of butyrate and acetate to CO2and ketones but increased oxidation of glucose and glutamine. Ammonia decreased cellular concentrations of oxaloacetate for all substrates evaluated. The extent to which butyrate carbon was oxidized to CO2after entering the tricarboxylic acid (TCA) cycle was not significantly influenced by ammonia, suggesting there was no major shift toward efflux of carbon from the TCA cycle. Ammonia reduced entry of butyrate carbon into the TCA cycle, and the proportion of CoA esterified with acetate and butyrate correlated positively with the production of CO2and ketone bodies. Also, ammonia reduced oxidation of propionate but had no effect on oxidation of 3-hydroxybutyrate. Inclusion of glucose, lactate, or glutamine with butyrate and acetate counteracted the ability of ammonia to decrease their oxidation. In rat colonocytes, it appears that ammonia suppresses short-chain fatty acid (SCFA) oxidation by inhibiting a step before or during their activation. This inhibition is alleviated by glucose and other energy-generating compounds. These results suggest that ammonia may only affect SCFA metabolism in vivo when glucose availability is compromised. |
| Databáze: | OpenAIRE |
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