Maternal chewing alleviates prenatal stress-related neuroinflammation mediated by microglia in the hippocampus of the mouse offspring

Abstract

Prenatal stress affects the hippocampal structure and function in pups. Maternal chewing ameliorates hippocampus-dependent cognitive impairments induced by prenatal stress. In this study, we investigated hippocampal microglia-mediated neuroinflammation in pups of dams exposed to prenatal stress with or without chewing during gestation. Methods: Pregnant mice were randomly assigned to control, stress, and stress/chewing groups. Stress and stress/chewing animals were subjected to restraint stress for 45 min three times daily from gestation day 12 to parturition, and were given a wooden stick to chew during the stress period. Four-month-old male pups were intraperitoneally administered with lipopolysaccharide (LPS). Serum corticosterone levels were determined 24 h after administration. The expression levels of hippocampal inflammatory cytokines were measured, and the microglia were analyzed morphologically. Results: Prenatal stress increased serum corticosterone levels, induced hippocampal microglia priming, and facilitated the release of interleukin-1β and tumor necrosis factor-α in the offspring. LPS treatment significantly increased the effects of prenatal stress on serum corticosterone levels, hippocampal microglial activation, and hippocampal neuroinflammation. Maternal chewing significantly inhibited the increase in serum corticosterone levels, suppressed microglial overactivation, and normalized inflammatory cytokine levels under basal prenatal stress conditions as well as after LPS administration. Conclusions: Our findings indicate that maternal chewing can alleviate the increase in corticosterone levels and inhibit hippocampal microglia-mediated neuroinflammation induced by LPS administration and prenatal stress in adult offspring.

Prenatal Stress Modifies Spatial Cognition in Mice: Effects of Age and Sex

“…Additionally, despite subjecting the dams to prenatal stress 3 times daily for eleven days, the dams may have received comparatively less stress through behavioral coping skills during the gestational restraint stress procedure such as maternal chewing behavior (Hisada et al, 2023). However, we have shown that prenatal stress impacts the behavioral outcomes in Swiss Webster mice, indicating that this prenatal stress exposure is successful in another strain of mouse.…”

“…Additionally, despite subjecting the dams to prenatal stress 3 times daily for eleven days, the dams may have received comparatively less stress through behavioral coping skills during the gestational restraint stress procedure such as maternal chewing behavior (Hisada et al, 2023).…”

Resveratrol ameliorates maternal immune activation-associated cognitive impairment in adult male offspring by relieving inflammation and improving synaptic dysfunction

“…Maternal exposure to LPS during the late stages of gestation led to an increase in inflammatory cytokine concentrations through a series of downstream signaling pathways. These cytokines could cross the maternalplacenta barrier and induce an inflammatory response in the fetus (Hisada et al, 2023). Previous studies have demonstrated that maternal exposure to LPS induced the activation of microglia/ macrophages and stimulated the release of inflammatory cytokines such as IL-1β, IL-6, and TNF-α in the brains of offspring (Dominguez Rubio et al, 2017;Rahimi et al, 2020).…”