Trial Parameters
Brief Summary
The study aims to investigate the effects of a 6-week leucine challenge on brain chemistry, connectivity, and behavior in people with midlife depression. The researchers will compare the leucine and an active comparator arm (lysine) for 6 weeks.
Eligibility Criteria
Inclusion Criteria: * Able and willing to provide informed consent * Diagnosis of major depression per Structured Interview for DSM-V (SCID-V) * Moderate to severe depression- Inventory of Depressive Symptoms - Self Reported (IDS-SR score \>34). * SHAPS score \>30 on the 0-56 scale * Body mass index (BMI) between 20-35 kg/m2 * Plasma CRP \>1 mg/L * No contraindications to MRI * Availability of friends or family for transportation after lumbar puncture procedure * Clinically significant findings on EKG * Patient Health Questionnaire (PHQ-9) score greater than 10 * Willingness to adopt contraceptive measures. Persons exempt from contraception requirements are: * Persons assigned male at birth * Persons assigned female at birth who: * have undergone a hysterectomy or bilateral oophorectomy; or * have been naturally postmenopausal for at least 24 consecutive months (i.e., has NOT had menses at any time in the preceding 24 consecutive months) Exclusion Criteria: * Leucine-Specific: * Histor