Sex Differences in the Brain-Blood Barrier in Rats Exposed to Early life Stress and the Treatment with Antidepressants and Psychobiotic

Abstract Major depressive disorder is a debilitating mental disorder. Although the etiology is not fully understood, the impairment to the blood-brain barrier (BBB) integrity may be involved. Maternal deprivation was performed in the first 10 postnatal days for 3h/day. Male and female rats were divided into control and maternal deprivation. Maternal deprivation animals were subdivided and received treatment with saline, escitalopram, ketamine, or probiotic. The integrity of BBB was evaluated in the prefrontal cortex and hippocampus at postnatal days 11, 21, 41, and 61. Maternal deprivation caused BBB breakdown in the prefrontal cortex and hippocampus in female and male rats in all ages evaluated, except in the prefrontal cortex of females at postnatal day 41. In females, escitalopram, ketamine, and probiotic reversed BBB breakdown in all ages evaluated, except probiotic at postnatal day 21 (prefrontal cortex), and ketamine at postnatal days 21 and 41 (hippocampus). In males, escitalopram, ketamine, and probiotic reversed BBB breakdown in the prefrontal cortex in all ages evaluated, except escitalopram at postnatal days 41 and 61. In the hippocampus of males, BBB damage was reversed by escitalopram at postnatal day 21 and ketamine at postnatal day 41. Treatment with escitalopram, ketamine, or probiotics can prevent changes in the BBB integrity, depending on the age and sex of the animal. Clinically it is important to evaluate different treatments depending on age and sex.