Perhaps the most famous example of this phenomena is that children of Holocaust survivors have altered levels of stress hormones, which may increase the risk of mental health issues, even if those children were conceived during peacetime.
Scientists at the University of New South Wales, Columbia University, and the University of Melbourne now report that giving those first generation offspring probiotics may prevent the transmission of potential detrimental effects to their own children.
The scientists used Lacidofil, which contains 95% Lactobacillus rhamnosus R0011 and 5% Lactobacillus helveticus R0052 (Lallemand Health Solutions).
“Regardless of the ultimate mechanism, the ease of administration, minimal risk, low cost, and general public acceptance of probiotics make them an ideal candidate to investigate as a first line of defense against stress-induced vulnerabilities,” wrote the authors in Psychological Science.
“The fact that early life adversity is often highly comorbid with poor nutrition and gastrointestinal problems further strengthens the case for probiotic interventions in stress and mental illness. Note that the probiotic used in the current studies already has established safety and efficacy in pediatric populations because it is frequently used in the treatment of gastrointestinal diseases.
“Together with these past studies, the current data make a strong case for further investigations into the clinical efficacy of these particular probiotic strains for the treatment of stress-related emotional health problems in children.”
The researchers examined the effects of paternal stress on the mental health of the offspring by assessing how long the animals retained any aversive associations and when they stopped with the aversive associations.
Almost 400 animals across three generations were used in the study: For the first generation, some of the animals were separated from their mothers (maternal separation or MS group) between two and 14 days after birth (compared to other that were weaned between 21 and 23 days after birth: the standard rearing or SR group). Males in the first generation (F0) group, were further divided into subgroups, with some given the probiotic for 12 days.
The first generation males mated with females to produce a second generation (F1), which were subjected to the MS or SR treatment, with or without the probiotic intervention.
Results showed that second generation rats of the males subjected to maternal separation in the first generation did show “longer-lasting aversive associations and greater relapse after extinction […] compared with the offspring of rats not exposed to maternal separation”, said the researchers.
“These data are the first to demonstrate that stress-induced behavioral alterations in affective learning could be “inherited” by infant offspring,” wrote the researchers. “This is important clinically because transmitted behavioral alterations that are detectable early in development are a useful target for intervention.”
Probiotic administration was associated with a reversal of these generational effects, and these benefits were observed whether the probiotic was given to the first or second generation animals.
“These findings suggest that behavioral phenotypes that are putatively involved in vulnerability to later-life anxiety, and that are transmitted across generations through fathers, can be effectively prevented or treated with noninvasive probiotic manipulations.”
Source: Psychological Science
Volume 27, Number 9, Pages 1171–1180, doi: 10.1177/0956797616653103
“Treating Generational Stress: Effect of Paternal Stress on Development of Memory and Extinction in Offspring Is Reversed by Probiotic Treatment”
Authors: B.L. Callaghan, C.S.M. Cowan, R. Richardson