Prenatal stress induced depressive-like behavior and region dependently high CRP level in offspring rats

Geniposide improves depression-like behavior in prenatal stress male offspring through restoring HPA axis- and glucocorticoid receptor-associated dysfunction

AIMS

Prenatal stress (PS) has an important impact on the brain development of offspring, which can lead to attention deficits, anxiety and depression in offspring. Geniposide (GE) is a kind of iridoid glycoside extracted from Gardenia jasminoides Ellis. It has various pharmacological effects and has been proved that have antidepressant effects. The aim of this study was to investigate the effect of GE on depression-like behavior in PS-induced male offspring mice and explore the possible molecular mechanisms.

METHODS

We used a prenatal restraint stress model, focusing on male PS-induced offspring mice to study the effects of GE.

KEY FINDINGS

The results showed that GE administration for 4 weeks significantly improved the depression-like behavior in PS offspring mice, which was manifested by markedly increasing the sucrose preference of PS offspring and the activity in the open field test, and reducing the immobility time in the forced swimming test. In addition, GE significantly reduced the levels of hypothalamic-pituitary-adrenal (HPA) axis-related hormones and exceedingly increased the protein expression of MAP2 and GAP43 in PS offspring. Furthermore, GE increased Glucocorticoid receptors (GR) nuclear translocation in the hippocampus of PS offspring, and enhanced the expression of synaptic plasticity-related proteins.

CONCLUSION

The results of this study showed that GE exerts antidepressant effects in male PS offspring mice by regulating the HPA axis, GR function and proteins related to synaptic plasticity.

Vulnerability and resilience to prenatal stress exposure: behavioral and molecular characterization in adolescent rats

Exposure to stress can lead to long lasting behavioral and neurobiological consequences, which may enhance the susceptibility for the onset of mental disorders. However, there are significant individual differences in the outcome of stress exposure since only a percentage of exposed individuals may show pathological consequences, whereas others appear to be resilient. In this study, we aimed to characterize the effects of prenatal stress (PNS) exposure in rats at adolescence and to identify subgroup of animals with a differential response to the gestational manipulation. PNS adolescent offspring (regardless of sex) showed impaired emotionality in different pathological domains, such as anhedonia, anxiety, and sociability. However, using cluster analysis of the behavioral data we could identify 70% of PNS-exposed animals as vulnerable (PNS-vul), whereas the remaining 30% were considered resilient (PNS-res). At the molecular level, we found that PNS-res males show a reduced basal activation of the ventral hippocampus whereas other regions, such as amygdala and dorsal hippocampus, show significant PNS-induced changes regardless from vulnerability or resilience. Taken together, our results provide evidence of the variability in the behavioral and neurobiological effects of PNS-exposed offspring at adolescence. While these data may advance our understanding of the association between exposure to stress during gestation and the risk for psychopathology, the investigation of the mechanisms associated to stress vulnerability or resilience may be instrumental to develop novel strategies for therapeutic intervention.

The effect of prenatal stress on offspring depression susceptibility in relation to the gut microbiome and metabolome

Prenatal stress (PS) increases offspring susceptibility to depression, but the underlying mechanism remains unclear. Our previous results showed that PS can affect depression-like behavior in offspring through neurotransmitters and neuroinflammatory substances in the hippocampus and frontal cortex. In recent years there has been increasing evidence for a role of the gut microbiome in depression. The brain-gut axis theory suggests there is a need to further explore the mechanism involving the gut microbiome in the susceptibility of offspring to depression caused by PS. In the present study we used a stress model relevant to depression in which pregnant female rats undergo prenatal restraint stress and the offspring show susceptibility to depression. High-resolution gene sequencing for 16S ribosomal RNA markers and non-targeted metabolomic analysis were used to evaluate the fecal microbiome and the availability of metabolites, respectively. PS was found to induce depressive-like behavior in susceptible offspring (PS-S), as detected by the sucrose preference and forced swimming tests, as well as altering Alpha and Beta diversity. The different microbiota between the PS-S and control groups were mainly involved in membrane transport, carbohydrate metabolism, amino acid metabolism, and replication and repair pathways. In total, 237 and 136 important differential metabolites with significant influence on modeling analysis were obtained under positive and negative modes, respectively. The main canonical pathways found to be altered were glycerophospholipid metabolism and glycerolipid metabolism. These results suggest that gut microbiota might contribute to the onset of PS-induced depression-like behavior by affecting the glycerophospholipid and glycerolipid metabolic pathways.

Prenatal stress induced depressive-like behavior and region dependently high CRP level in offspring rats

INTRODUCTION

To explore the changes in C-reactive protein (CRP) level in different regions of one old offspring rats exposed to prenatal stress (PS).

METHODS

The rat model was constructed with prenatal restraint stress on pregnant dams on days 14-20 of gestation. Offspring rats were randomly divided into PS susceptibility (PS-S) group and control (CON) group. Behavioral experiments including sucrose preference test (SPT), open-field test (OFT), and forced swimming test (FST) were used to measure depressive-like behaviors. Immunohistochemistry, qRT-PCR, and Western blotting were applied to detect the changes in CRP level.

RESULTS

The results showed that PS could cause depressive-like behaviors in all SPT, OFT, and FST. Concomitantly, CRP mRNA and protein expression significantly increased in hippocampus, prefrontal cortex, and hypothalamus in the PS-S group when compared that in the CON group, while no significantly changes in liver, heart, olfactory bulb, striatum, and cerebellum in the PS-S group when compared that in the CON group.

CONCLUSION

Increasing of CRP expression in hippocampus, prefrontal cortex, and hypothalamus may play a critical role in the mechanism under depressive-like behavior in offspring rats exposed to PS.