TNF and obesity due to melanocortin 4 receptor deficiency: Despite the advantages of selectively investigating a role for IL-6 trans-signaling in obesity-linked VT, our data (Figure 5) revealed that while overactive IL-6-trans-signaling ΔQTc was statistically significant, it was less remarkable than the effects of HFD, suggesting that other cytokines (IL-1β, TNF-α, IL-18, Figure 2) likely contributed to the HFD-linked ΔQTc.