Figure 10.

Serum cytokine levels day 70 post-infection. On day 70 post-infection, blood was collected and processed as described earlier. Minimum levels of detection in picogramme per millilitre are 1.1 for interleukin 6 (IL-6), 1.1 for interferon (IFN)-gamma and 2.3 for tumour necrosis factor (TNF)-alpha. Each bar represents the mean (+/ standard error of the mean) concentration in picogramme per millilitre. The number of pools (n=5) is listed for each group. Serum IL-6 (A), TNF-alpha (B) and IFN-gamma (C) levels were determined using Luminex XPONENT for Magpix. (A) IL-6: infected mice fed with an HFD have increased IL-6 levels compared with uninfected mice fed with a HFD and to infected RD-fed mice. No difference is observed between RD-fed infected and RD-fed non-infected groups. (B) TNF-alpha: TNF-alpha levels did not alter significantly between any of the groups, regardless of diet/treatment or infection status. (C) IFN-gamma: serum levels of IFN-gamma were significantly higher in infected HFD mice treated with metformin. Several in vivo and in vitro studies have demonstrated that IFN-gamma enhances macrophage killing of Trypanosoma cruzi and resistance to T. cruzi (Note: our protocol included measuring serum cytokines at day 30, but these specimens were lost during processing).