IL6 and depressive disorder: They used the current feasibility study using functional neuroimaging and biospecimen data to identify whether changes in inflammatory markers, fecal short-chain fatty acids, as well as neural circuit-based targets predicted depression and anxiety outcomes in comorbid obese participants, and preliminary correlation analyses showed significant correlated changes in three inflammatory markers (IL-1RA, IL-6, and TNF-α) and five neural targets (negative influence circuit, positive influence circuit, and default mode circuit) at 2 months [139].