Oxidative and Nitrosative Stress in Major Depressive Disorder: A Case Control Study

Area of Science:

• Neuroscience
• Biochemistry
• Psychiatry

Background:

• Oxidative stress and nitric oxide (NO) pathway alterations are implicated in major depressive disorder (MDD).
• These pathways interact but haven't been studied simultaneously in MDD.
• This study investigated oxidative and nitrosative stress in neutrophils (PMNs) of drug-naive MDD patients and their relatives.

Purpose of the Study:

• To assess and compare oxidative and nitrosative stress markers in PMNs of drug-naive MDD patients and their first-degree relatives.
• To explore the familial association of these stress pathways in MDD.

Main Methods:

• Included 29 drug-naive MDD patients, 27 healthy first-degree relatives, and controls (aged 18-45).
• Measured reactive oxygen species (ROS), nitrites, neuronal NO synthase (nNOS), myeloperoxidase in PMNs, and serum cortisol.

Main Results:

• MDD patients showed significantly higher ROS, myeloperoxidase, nNOS mRNA in PMNs, and serum cortisol compared to controls.
• First-degree relatives also exhibited increased myeloperoxidase and serum cortisol.
• Both patients and relatives had significantly lower PMN and plasma nitrite levels.
• Positive correlations were found between ROS, nitrite levels, and serum cortisol in MDD patients and their relatives.

Conclusions:

• Neutrophil oxidative/nitrosative stress, plasma nitrite, and serum cortisol are positively correlated between MDD patients and their first-degree relatives.
• Findings suggest a familial component to these biochemical alterations in MDD.
• Further research with larger samples is needed to validate these pathways as potential early biomarkers for psychopathology risk.