Helicobacter pylori infection and low dietary iron alter behavior, induce iron deficiency anemia, and modulate hippocampal gene expression in female C57BL/6 mice.

Helicobacter pylori (H.pylori), a bacterial pathogen, is a causative agent of gastritis and peptic ulcer disease and is a strong risk factor for development of gastric cancer. Environmental conditions, such as poor dietary iron resulting in iron deficiency anemia (IDA), enhance H.pylori virulence and increases risk for gastric cancer. IDA affects billions of people worldwide, and there is considerable overlap between regions of high IDA and high H.pylori prevalence. The primary aims of our study were to evaluate the effect of H.pylori infection on behavior, iron metabolism, red blood cell indices, and behavioral outcomes following comorbid H. pylori infection and dietary iron deficiency in a mouse model. C57BL/6 female mice (n = 40) were used; half were placed on a moderately iron deficient (ID) diet immediately post-weaning, and the other half were maintained on an iron replete (IR) diet. Half were dosed with H.pylori SS1 at 5 weeks of age, and the remaining mice were sham-dosed. There were 4 study groups: a control group (-Hp, IR diet) as well as 3 experimental groups (-Hp, ID diet; +Hp, IR diet; +Hp,ID diet). All mice were tested in an open field apparatus at 8 weeks postinfection. Independent of dietary iron status, H.pylori -infected mice performed fewer exploratory behaviors in the open field chamber than uninfected mice (p<0.001). Hippocampal gene expression of myelination markers and dopamine receptor 1 was significantly downregulated in mice on an ID diet (both p<0.05), independent of infection status. At 12 months postinfection, hematocrit (Hct) and hemoglobin (Hgb) concentration were significantly lower in +Hp, ID diet mice compared to all other study groups. H.pylori infection caused IDA in mice maintained on a marginal iron diet. The mouse model developed in this study is a useful model to study the neurologic, behavioral, and hematologic impact of the common human co-morbidity of H. pylori infection and IDA.

Adolescent experience affects postnatal ultrasonic vocalizations and gene expression in future offspring.

The present study measured postnatal ultrasonic vocalization (USV) and gene expression to examine potential changes in communication and/or attachment in the offspring of mothers exposed to morphine during adolescence. Offspring of morphine-exposed (Mor-F1), saline-exposed (Sal-F1), or non-handled control (Con-F1) female Sprague-Dawley rats were tested for separation-induced distress calls and maternal potentiation of distress calls during early postnatal development. We also examined relative expression of dopamine D2 receptor and mu opioid receptor (oprm1) mRNA in the nucleus accumbens and hypothalamus in these offspring, as their activity has been implicated in the regulation of postnatal USV in response to maternal separation. The findings indicate that adolescent experiences of future mothers, including their 10 daily saline or morphine injections, can result in significant region-specific differences in gene expression. In addition, these experiences resulted in fewer numbers of separation-induced distress calls produced by offspring. In contrast, augmented maternal potentiation was only observed in Mor-F1 offspring. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58:714-723, 2016.