Reserpine-induced model of stress suppresses mucosal immunity

New insights into the neurobiological mechanisms of major depressive disorders

OBJECTIVE

To review the current evidence about the neurobiological mechanisms in major depressive disorders (MDD) and the key findings from studies using neuroimaging tools and animal models.

METHOD

This paper gives an overview of the role of genetic and environmental factors in the pathophysiology of MDD and describes the structural changes in brain structures of depressed individuals. A closer look is given at the molecular processes and neurotransmitters implicated in this mental disorder. Moreover, this paper discusses key findings from recent research using animal models and their relevance for clinical applications.

RESULTS

Although the exact cause of MDD is not known, there is enough evidence showing that genetic, psychological and environmental factors significantly increase the risk of developing this disease. Individuals affected by MDD exhibit a reduced volume of structures such as the amygdala, hippocampus and basal ganglia, as well as altered level of neurotransmitters in the brain.

CONCLUSION

The studies presented in this review show promising results that could shed light on the molecular mechanisms of MDD. However, more work needs to be done to better understand this psychiatric disorder and promote the development of new treatment strategies.

The effect of restraint stress on experimental colitis is IFN-gamma independent

Stress, a protective reaction to external threats, may be deleterious if linked to an inflammatory stimulus. Stress may influence intestinal immunity, thereby contributing to the development of colitis. Less severe histological abnormalities and clinical scores were detected in dextran sulphate sodium (DSS)-induced colitis in IFN-gamma(-/-), compared to Wt, mice. Disease severity was increased by restraint stress in DSS-treated IFN-gamma(-/-) and Wt mice, accompanied by suppressed colonic pro and anti inflammatory cytokine responses. Our data suggest that IFN-gamma is important in the development of acute colitis. Stress increases the severity of colitis, but is independent of the IFN-gamma pathway.