Cranberries show potential as an anti-inflammatory therapeutic due to their high levels of polyphenol compounds. However, evidence on the anti-inflammatory effects of cranberry is from studies of polyphenol fractions at doses higher than those circulating in human serum post-supplementation. THP-1 macrophages were pre-incubated with serum from cranberry or placebo supplemented individuals, followed by LPS stimulation to determine potential anti-inflammatory effects of serum metabolites. We first aimed to determine baseline levels of inflammation and functional ability of macrophages in an older-overweight population compared to younger-athletic individuals. Results showed that serum from older individuals was less effective at overcoming cytotoxic effects of LPS on macrophages, compared to younger subjects. Macrophages exposed to serum from older subjects also exhibited lower levels of phagocytosis and expression of molecules associated with activation of adaptive immunity than younger-athletic subjects. We also aimed to determine whether cranberry supplementation could alleviate LPS-induced inflammation or alter macrophage functioning in older subjects. When older subjects were given an eight-week cranberry supplement, their serum did not lower levels of inflammation or alter macrophage functioning in our model of inflammation, compared to serum from placebo supplemented controls. We conclude that the ingestion of cranberry polyphenols was not anti-inflammatory in our model
