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Abstract
Advanced glycation end products (AGEs) are formed during the Maillard reaction when cooking foods using high heat and low moisture. Pet food processing uses high temperatures to increase safety by reduction of microbial load and allow storage. Dietary AGEs have been implicated as a risk factor for development of obesity and other diseases in human beings suggesting that high dietary intake by dogs may be detrimental to their health. Soluble RAGE (sRAGE) acts as a decoy receptor that binds AGEs preventing cellular RAGE activation and inflammation.
We measured the AGEs carboxymethyllysine (CML), carboxyethyllysine (CEL) and methylglyoxal hydroimidazolone-1 (MG-H1) in four differently processed diets (two high heat – canned wet and dry kibble; two low heat – air-dried and mildly cooked/raw) and plasma levels of CML, CEL, MG-H1, glyoxal hydroimidazolone-1 (GH-1) and argpyrimidine (AP) via mass spectrometry, to determine the influence of dietary AGE intake on plasma levels. Serum concentrations of sRAGE were determined by immunoassay. High heat processed diets contained higher total AGEs that influenced plasma AGEs while sRAGE levels did not change.
We proposed that differently processed diets containing varied amounts of AGEs will alter the serum and urine metabolome. Nuclear magnetic resonance (NMR) spectroscopy was used to determine serum and urine metabolic changes. We identified eight discriminatory metabolites in serum and six in urine, and observed lower metabolite concentrations with the dry kibble. Serum and urine metabolite profiles fluctuated minimally over the feeding period for each diet.
We hypothesized that the fecal microbiome would change in response to the four differently processed diets. Microbiome analysis via 16S rRNA sequencing showed a decrease in -diversity with the dry kibble, changes in genera and higher microbial, but non-pathogenic, load of the low heat processed diets.
This work demonstrates how processing methods and associated dietary AGE levels, by way of its metabolic transit through the canine body, can predispose dogs to diseases as in human beings. Further investigations are recommended to provide additional information that can guide pet food processing and nutritional management of inflammatory and degenerative diseases in dogs related to dietary AGE intake.
We measured the AGEs carboxymethyllysine (CML), carboxyethyllysine (CEL) and methylglyoxal hydroimidazolone-1 (MG-H1) in four differently processed diets (two high heat – canned wet and dry kibble; two low heat – air-dried and mildly cooked/raw) and plasma levels of CML, CEL, MG-H1, glyoxal hydroimidazolone-1 (GH-1) and argpyrimidine (AP) via mass spectrometry, to determine the influence of dietary AGE intake on plasma levels. Serum concentrations of sRAGE were determined by immunoassay. High heat processed diets contained higher total AGEs that influenced plasma AGEs while sRAGE levels did not change.
We proposed that differently processed diets containing varied amounts of AGEs will alter the serum and urine metabolome. Nuclear magnetic resonance (NMR) spectroscopy was used to determine serum and urine metabolic changes. We identified eight discriminatory metabolites in serum and six in urine, and observed lower metabolite concentrations with the dry kibble. Serum and urine metabolite profiles fluctuated minimally over the feeding period for each diet.
We hypothesized that the fecal microbiome would change in response to the four differently processed diets. Microbiome analysis via 16S rRNA sequencing showed a decrease in -diversity with the dry kibble, changes in genera and higher microbial, but non-pathogenic, load of the low heat processed diets.
This work demonstrates how processing methods and associated dietary AGE levels, by way of its metabolic transit through the canine body, can predispose dogs to diseases as in human beings. Further investigations are recommended to provide additional information that can guide pet food processing and nutritional management of inflammatory and degenerative diseases in dogs related to dietary AGE intake.