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Title: Cellular metabolism and IL-6 concentrations during stimulated inflammation in small and large dog breeds’ primary fibroblasts cells, as they age
The immune system undergoes marked changes during aging characterized by a state of chronic, low-grade inflammation, so called inflammaging. Domestic dogs are the most morphological and physiological diverse group of mammals, with the widest range in body masses for a single species. Additionally, smaller dogs tend to live significantly longer than larger dogs across all breeds. Body mass is intricately linked to mass-specific metabolism and aging rates, thus, dogs are exemplary for studies in inflammaging. Dermal fibroblasts cells play an important role in skin inflammation, and as such, are a good cell type to determine inflammatory patterns in dogs. Here, we examine aerobic and glycolytic cellular metabolism, and IL-6 concentrations in primary fibroblast cells isolated from small and large, young and old dogs when treated with lipopolysaccharide (LPS) from Escherichia coli to stimulate an inflammatory phenotype. We found no differences in cellular metabolism of any group when treated with LPS. Unlike mice and humans, there was a less drastic amplification of IL-6 concentration after LPS treatment in the geriatric population of dogs compared with puppies. We also found evidence that large breed puppies have significantly less background or control IL-6 concentrations compared with small breed puppies. This implies that the more » patterns of inflammaging in dogs may be distinct and different from other mammals commonly studied. « less
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Journal of Experimental Biology
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National Science Foundation
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