Psychotropic effects of Lactobacillus plantarum PS128® in early life-stressed and naïve adult mice.
Liu YW, Liu WH, Wu CC, Juan YC, Wu YC, Tsai HP, Wang Sabrina*, Tsai YChieh*. (2016) Psychotropic effects of Lactobacillus plantarum PS128® in early life-stressed and naïve adult mice. Brain Res. 1631:1-12.
Ingestion of specific probiotics, namely “psychobiotics”, produces psychotropic effects on
behavior and affects the hypothalamic–pituitary–adrenal axis and neurochemicals in the
brain. We examined the psychotropic effects of a potential psychobiotic bacterium,
Lactobacillus plantarum strain PS128® (PS128®), on mice subjected to early life stress (ELS)
and on naïve adult mice. Behavioral tests revealed that chronic ingestion of PS128®
increased the locomotor activities in both ELS and naïve adult mice in the open field test.
In the elevated plus maze, PS128® significantly reduced the anxiety-like behaviors in naïve
adult mice but not in the ELS mice; whereas the depression-like behaviors were reduced in
ELS mice but not in naïve mice in forced swimming test and sucrose preference test. PS128® administration also reduced ELS-induced elevation of serum corticosterone under both
basal and stressed states but had no effect on naïve mice. In addition, PS128® reduced
inflammatory cytokine levels and increased anti-inflammatory cytokine level in the serum
of ELS mice. Furthermore, the dopamine level in the prefrontal cortex (PFC) was
significantly increased in PS128® treated ELS and naïve adult mice whereas serotonin (5-
HT) level was increased only in the naïve adult mice. These results suggest that chronic
ingestion of PS128® could ameliorate anxiety- and depression-like behaviors and modulate
neurochemicals related to affective disorders. Thus PS128® shows psychotropic properties
and has great potential for improving stress-related symptoms.