Parental Depression: Animal Models of an Adverse Life Event (original) (raw)
Related papers
Maternal postnatal depression predicts altered offspring biological stress reactivity in adulthood
Psychoneuroendocrinology, 2015
The offspring of depressed parents have been found to show elevated basal levels of the stress hormone cortisol. Whether heightened cortisol stress reactivity is also present in this group has yet to be clearly demonstrated. We tested whether postnatal maternal depression predicts subsequent increases in offspring biological sensitivity to social stress, as indexed by elevated cortisol reactivity. Participants (mean age 22.4-years) derived from a 22-year prospective longitudinal study of the offspring of mothers who had postnatal depression (PND group; n=38) and a control group (n=38). Salivary cortisol response to a social-evaluative threat (Trier Social Stress Test) was measured. Hierarchical linear modelling indicated that PND group offspring showed greater cortisol reactivity to the stress test than control group participants. Group differences were not explained by offspring depressive or anxiety symptoms, experiences of negative life events, elevated basal cortisol at age 13-y...
Divergent maternal behavioral patterns in two genetic animal models of depression
Physiology & Behavior, 2009
Maternal behavior was examined in Flinders Sensitive-Line (FSL) and Wistar-Kyoto (WKY) rats, two different genetic animal models of depression. Behavioral patterns were assessed by undisturbed observations in the nest [Post-Partum Days (PPD) 4 and 9] and post-disturbance observations ("retrieval tests") on PPD 10. Litters were randomly allocated to a mild chronic-stress condition (limiting available bedding between PPD 2 and 9) or a standard rearing condition. The findings indicated that FSL dams did not differ from control dams in the undisturbed observations. However, in the post-disturbance observations FSL dams exhibited less pupdirected behaviors, a shorter latency to first pup carrying/retrieval and more self-directed behaviors than controls (the latter effect only in dams' interaction with whole litter). In contrast, WKY dams performed more pup-directed activities (e.g., nursing and licking) and less self-directed activities in both the undisturbed and post-disturbance observations (in both dams' interaction with single-pup and with the whole-litter) compared to controls. Accordingly, WKY dams exhibited a shorter latency for first pup-licking bout (in both post-disturbance observations). The early life mild chronic-stress used in the study ('limited-bedding') had a minor effect on the dams' behavior. Overall, the study investigated for the first time the maternal behavior of WKY dams and suggests that these dams show an almost opposite behavioral pattern to that of FSL dams. The results are discussed with regard to earlier findings in the FSL strain and behavioral patterns documented in depressed human mothers.
Braw 2009- Divergent maternal behavioral patterns in two genetic animal models of depression
Maternal behavior was examined in Flinders Sensitive-Line (FSL) and Wistar-Kyoto (WKY) rats, two different genetic animal models of depression. Behavioral patterns were assessed by undisturbed observations in the nest [Post-Partum Days (PPD) 4 and 9] and post-disturbance observations ("retrieval tests") on PPD 10. Litters were randomly allocated to a mild chronic-stress condition (limiting available bedding between PPD 2 and 9) or a standard rearing condition. The findings indicated that FSL dams did not differ from control dams in the undisturbed observations. However, in the post-disturbance observations FSL dams exhibited less pupdirected behaviors, a shorter latency to first pup carrying/retrieval and more self-directed behaviors than controls (the latter effect only in dams' interaction with whole litter). In contrast, WKY dams performed more pup-directed activities (e.g., nursing and licking) and less self-directed activities in both the undisturbed and post-disturbance observations (in both dams' interaction with single-pup and with the whole-litter) compared to controls. Accordingly, WKY dams exhibited a shorter latency for first pup-licking bout (in both post-disturbance observations). The early life mild chronic-stress used in the study ('limited-bedding') had a minor effect on the dams' behavior. Overall, the study investigated for the first time the maternal behavior of WKY dams and suggests that these dams show an almost opposite behavioral pattern to that of FSL dams. The results are discussed with regard to earlier findings in the FSL strain and behavioral patterns documented in depressed human mothers.
Translational Psychiatry
Depressive mothers often find mother-child interaction to be challenging. Maternal stress may further impair mother-child attachment, which may increase the risk of negative developmental consequences. We used rats with different vulnerability to depressive-like behavior (Wistar and Kyoto) to investigate the impact of stress (maternal separation-MS) on maternal behavior and adolescent offspring cognition. MS in Kyoto dams increased pup-contact, resulting in higher oxytocin levels and lower anxiety-like behavior after weaning, while worsening their adolescent offspring cognitive behavior. Whereas MS in Wistar dams elicited higher quality of pup-directed behavior, increasing brain-derived neurotrophic factor (BDNF) in the offspring, which seems to have prevented a negative impact on cognition. Hypothalamic oxytocin seems to affect the salience of the social environment cues (negatively for Kyoto) leading to different coping strategies. Our findings highlight the importance of contextu...
Interdisciplinary toxicology, 2017
Depression is one of the most prevalent and life-threatening forms of mental illness affecting about 20% of the population. Depressive disorder as a biochemical phenomenon, was first recognized in the mid-20 century of research, however the etiology of this disease is still not well understood. Although the need to investigate depressive disorders has emerged from the needs of clinical practice, there are many preclinical studies, which brought new insights into this field of research. During experimental work it was crucial to develop appropriate animal models, where the neurohumoral mechanism was similar to humans. In the past decades, several animal models of maternal depression have been developed. We describe the three most popular rodent models of maternal depression which are based on 1. stress prior to gestation, 2. prenatal stress and 3. early life stress. The above-mentioned animal models appear to fulfill many criteria for a relevant animal model of depression; they alter...
Repeated long separations from pups produce depression-like behavior in rat mothers
Psychoneuroendocrinology, 2007
Long (LMS) versus brief (BMS) daily separations of rat pups from their mothers have contrasting effects on their adult stress responses and maternal behavior by respectively decreasing and increasing licking received from their mothers. We hypothesized that LMS decreases pup licking in mothers by inducing learned helplessness, creating a depression-like state. We subjected postpartum rats to LMS (3 h), BMS (15 min) or no separation (NMS) on postpartum days 2-14. After weaning, mothers were given a forced swim test (FST). LMS mothers exhibited more immobility and fewer escape attempts than BMS or NMS mothers. These results suggest that LMS induces a depressionlike state, which may account for the reductions in maternal behavior seen in LMS mothers. Immobility in the FST is recognized as an animal model of depression. Therefore, LMS may be a model of maternal depression.
Progress in Neuro-Psychopharmacology and Biological Psychiatry, 2006
In order to study the gene-environment interaction as well as investigate prophylactic/ameliorative effects of early intervention on development of adult life psychopathology, we superimposed maternal separation on an animal model of depression the Flinders Sensitive Line (FSL) rats and their controls the Flinders Resistant Line (FRL) rats and studied behavior following treatment with escitalopram. Animals were maternally separated for 180 min/day from postnatal day 2 (PND 2) to 14. The control groups were left undisturbed. Treatment with escitalopram or vehicle admixed to food pellets was commenced on PND 43 and continued until PND 73. The Porsolt swim test was carried out on PND 65. Baseline FRL/ FSL differences in body weight and swim duration, considered to be an inverse index of depression, were found (p's < 0.001). In the FSL, maternal separation further decreased swim duration (p < 0.001) while the FRL strain was unaffected. Escitalopram had no effect in FRL, but increased swim duration in both maternally non-separated and separated FSL (p < 0.05 and p = 0.001; respectively). These results confirm the strain differences between the FSL and FRL and demonstrate that the long-term effects of early life adverse experience will to a significant degree depend on the genetic make-up of an individual. Finally, antidepressant treatment reversed behavioral abnormalities caused by genetic and environmental factors. This study highlights the importance of genetic factors in susceptibility to early life adverse events, and demonstrates the efficiency of early antidepressant treatment in reversing behavioral abnormalities, both those caused by genetic factors and by environmental factors.
Brain, Behavior, and Immunity, 2005
Recent studies in humans suggest that alterations in the activity of the neuroendocrine system mediate the eVects of psychosocial stress on fetal development and birth outcome. Chronic maternal distress compromises the normal regulation of hormonal activity during pregnancy and elevates free circulating corticotrophin-releasing hormone (CRH), probably of placental origin, before the normal increase occurs at term. Excess CRH, and other hormones like cortisol and met-enkephalin that pass through the placenta, could precipitate preterm labor, reduce birth weight and slow growth rate in prenatally stressed infants. CRH and/or cortisol have also been associated with impaired fetal habituation to stimuli and temperamental diYculties in infants. These changes may result from actions of the hormones on their receptors in the fetal limbic system. In the rat, gestational stress and excess maternal and fetal plasma corticosterone cause downregulation of fetal glucocorticoid (GR) and mineralocorticoid (MR) receptors and impair the feedback regulation of the hypothalamic-pituitary adrenal (HPA) axis in infancy and adulthood. The impairment in HPA axis activity can be prevented by maternal adrenalectomy and mimicked by administration of glucocorticoids. Gestational stress also increases CRH activity in the amygdala and the incidence of anxiogenic and depressive-like behavior in rats and non-human primates, which can be ameliorated by CRH antagonists. Excess amounts of CRH and cortisol reaching the human fetal brain during periods of chronic maternal stress could alter personality and predispose to attention deWcits and depressive illness through changes in neurotransmitter activity.