IL6 and obesity due to melanocortin 4 receptor deficiency: The relative expression of interleukin (IL)-1β and IL-6 presented a hierarchic ascending trend in the four groups, from the control group, obese group, and periodontitis group to the combination group, which indicated that the status of obesity or periodontitis would work as an inducement alone to trigger increased levels of the pro-inflammatory cytokines IL-1β and IL-6, while the comorbidity model would amplify such an inflammatory effect.