Associations between Traumatic Brain Injury, Drug Abuse, Alcohol Use, Adverse Childhood Events, and Aggression Levels in Individuals with Foster Care History

Antibiotic-induced microbiota depletion in normally-reared adult rats mimics the neuroendocrine effects of early life stress

Early life stress induced by maternal separation (MS) causes neuroendocrine, behavioral, and metabolic alterations that are related to gut dysbiosis. MS also increases microglial activation and decreases neurogenesis. Whether these long-term alterations are maintained or worsened in the absence of gut microbiota remains unknown. Hence, this study evaluated the effect of MS symptomatology after antibiotic-induced microbiota depletion (AIMD) in adult rats. Control and maternally separated (3 h per day from postnatal day one to 14, MS180) rats were subjected to AIMD for one month, then assessed for behavioral, metabolic, and neuroendocrine responses. Effects of MS180 and AIMD on gut microbiota were confirmed by qPCR. The data indicate that MS180 caused a passive coping strategy in the forced swimming test and decreased hippocampal neurogenesis. In addition, fasting glucose, cholesterol, and corticosterone levels increased, which correlated with a decrease in Lactobacillus spp counts in the caecum. AIMD also increased immobility in the forced swimming test, decreased hippocampal neurogenesis, and augmented corticosterone levels. However, it had no effects on glucose homeostasis or plasma lipid levels. Furthermore, the MS180-induced long-term effects on behavior and neurogenesis were not affected by microbiota depletion. Meanwhile, the metabolic imbalance was partially reversed in MS180 + AIMD rats. These results show that AIMD mimics the behavioral consequences of MS180 but may prevent metabolic imbalance, suggesting that gut dysbiosis could be part of the mechanisms involved in the maintenance of the long-term consequences of early life stress.

A Life Course Study on Traumatic Brain Injury and Physical and Emotional Trauma in Foster Children

Foster children are exposed to high levels of abuse, violence, and other adverse events throughout their childhood and adolescent years. Forms of brain injury, notably traumatic brain injury (TBI), are understudied in the foster child population. This study aimed to explore different forms of brain injury and their cognitive, behavioral, and psychological/emotional effects on current and former foster children using a life course perspective. A thematic analysis with a life course perspective was used to examine semi-structured, open-ended interviews conducted with current and previous foster children between the ages of 16 and 29 years. The study included 47 participants: 25 males (53%) and 22 females (47%) with an average age of 21 years and an average of 11.2 years of education. Of 47 current and previous foster children between the ages of 16 and 29, two-thirds had sustained one or more TBIs. Through a thematic analysis, four overarching and inter-related themes emerged from the data: frequent TBI, normalization (of abuse, violence, injury, and neglect), emotional trauma, and dangerous coping methods such as alcohol use in 94% and recreational drug use in 81%. Normalization of adverse events, emotional trauma, and the use of dangerous coping methods occurred in 66%, 81%, and 49% of participants, respectively, and are the cumulative toxic long-term effects of early negative life experiences and repeated forms of brain injury. Early and continued exposure to TBI, abuse, violence, and/or neglect with continued maladaptive behaviors suggests that the participants may have experienced changes in brain structure and function over their lives that provided the milieu for continued vulnerability to personal and future injury to future generations. These behavioral and perceptual changes point to a toxic combination of injuries that result in continued vulnerability to repeated injury through contextual exposure to risks and maladaptive normalization, emotional trauma, and risky coping styles.