Running exercise protects the capillaries in white matter in a rat model of depression

Abstract

Running has been shown to improve depressive symptoms when used as an adjunct to medication. However, the mechanisms underlying the antidepressant effects of running are not fully understood. Changes of capillaries in white matter have been discovered in clinical patients and depression model rats. Considering the important part of white matter in depression, running may cause capillary structural changes in white matter. Chronic unpredictable stress (CUS) rats were provided with a 4-week running exercise (from the fifth week to the eighth week) for 20 minutes each day for 5 consecutive days each week. Anhedonia was measured by a behavior test. Furthermore, capillary changes were investigated in the control group, the CUS/Standard group, and the CUS/Running group using stereological methods. The 4-week running increased sucrose consumption significantly in the CUS/Running group and had significant effects on the total volume, total length, and total surface area of the capillaries in the white matter of depression rats. These results demonstrated that exercise-induced protection of the capillaries in white matter might be one of the structural bases for the exercise-induced treatment of depression. It might provide important parameters for further study of the vascular mechanisms of depression and a new research direction for the development of clinical antidepressant means. J. Comp. Neurol. 524:3577-3586, 2016. © 2016 Wiley Periodicals, Inc.

Exercise protects myelinated fibers of white matter in a rat model of depression

“…In the present study, 4 weeks of exercise induced a significant improvement in anhedonia, the core depressive symptom, which was reflected in the significantly higher sucrose consumption by the running model group than by the model control group on the SPT. This result was consistent with the conclusion of the studies by Blumenthal et al, as well as a large number of previous reports that affirmed the counteractive effects of running exercise on stress-induced anhedonia (Archer, Josefsson, & Lindwall, 2014;Chen et al, 2016;Wen et al, 2014), and the current results further demonstrated the efficacy of exercise against depression.…”

Stereological Study on the Positive Effect of Running Exercise on the Capillaries in the Hippocampus in a Depression Model

“…The rats in the CUS/Running group were forced to run on a six-lane motorized treadmill. The exercise protocol was similar to that of a previous study (Chen et al, 2016 ).…”

“…The main CUS process was described in a previous study (Chen et al, 2016 ). The basic steps are as follows: the rats were randomly divided into two groups: control group ( n = 10) and CUS group ( n = 90).…”

“…Sampling methods were described by our previous work (Chen et al, 2016 ). The obtained slabs were embedded in optimal cutting temperature compound (OCT) to obtain frozen sections, and the sector technique was used to produce isotropic and uniformly random (IUR) sections (Chao et al, 2015 ).…”

“…Swain et al ( 2003 ) found that after 30 days of running exercise, in 6- to 12-month-old rats the volume fraction of the cortex capillaries is increased in the II/III layer of the motor cortex. Using unbiased stereological methods, our previous work revealed that after running exercise the total length, total volume and total surface area of the capillaries in the cortex of aged rats (Huang et al, 2013 ) and in white matter in a rat model of depression (Chen et al, 2016 ) are increased. In treating vascular depression, greater depression reduction and lower rates of recurrence are found when combined antidepressant therapy with vasodilator drug (nimodipine), which supported the argument that cerebrovascular disease is related to the pathogenesis and recurrence of depression in patients (Taragano et al, 2001 ).…”