Yoon HS, et al. - Researchers here assessed if whether CART peptide levels are altered in the cerebrospinal fluid (CSF) of patients with MDD patients and are correlated with MDD symptoms. In this work, patients with MDD showed reduced CSF CART peptide levels compared to healthy controls. The CART levels were observed to had negative correlations with antidepressant dose and some symptoms, supporting the possibility that CART peptide is involved in the development of depressive symptoms.