Recent Advances in Translational Magnetic Resonance Imaging in Animal Models of Stress and Depression

Abstract

Magnetic resonance imaging (MRI) is a valuable translational tool that can be used to investigate alterations in brain structure and function in both patients and animal models of disease. Regional changes in brain structure, functional connectivity, and metabolite concentrations have been reported in depressed patients, giving insight into the networks and brain regions involved, however preclinical models are less well characterized. The development of more effective treatments depends upon animal models that best translate to the human condition and animal models may be exploited to assess the molecular and cellular alterations that accompany neuroimaging changes. Recent advances in preclinical imaging have facilitated significant developments within the field, particularly relating to high resolution structural imaging and resting-state functional imaging which are emerging techniques in clinical research. This review aims to bring together the current literature on preclinical neuroimaging in animal models of stress and depression, highlighting promising avenues of research toward understanding the pathological basis of this hugely prevalent disorder.

White Matter Changes Following Chronic Restraint Stress and Neuromodulation: A Diffusion Magnetic Resonance Imaging Study in Young Male Rats

“…However, the DTI and DKI results are less clear-cut. Microstructural disruption in WM, axonal degeneration, and demyelination in depression are generally believed to produce higher RD and MD and lower FA in both patients with depression ( 11 , 59 , 60 , 61 ) and animal models of depression ( 62 , 63 ), such as the Wistar–Kyoto strain genetic model ( 14 ) and chronic unpredicted mild stress model ( 13 ). Keeping in mind that relating DTI and DKI measures to tissue microstructure is difficult, our observation of higher FA values being driven by a decrease in RD and MD contradicts the above-mentioned studies.…”

Neural cell adhesion molecule Negr1 deficiency in mouse results in structural brain endophenotypes and behavioral deviations related to psychiatric disorders

“…Reduced total brain and hippocampal volume has been observed in several animal models, such as a SCZ model 46 , a MDD model 47 , ASD model 48 , and a post-traumatic stress disorder (PTSD) model 49 . Smaller globus pallidus in Negr1 −/− mice is indicative of disrupted cortico-basal ganglia circuitry and/or connections of the limbic pallidum with the dopaminergic system 50 .…”

Lack of FKBP51 Shapes Brain Structure and Connectivity in Male Mice

“…Similarly, Laine et al demonstrated that mice exposed to chronic social defeat stress showed significantly more activation in several brain regions known to regulate depressive and anxiety‐like behavior 21 . In a recent review, McIntosh et al concluded that increased lateral ventricular volume and decreased hippocampal volume are relatively consistent hallmarks in both patients with MDD and animals model 22 …”