22 research outputs found
Prenatal stress programs neuroendocrine stress responses and affective behaviors in second generation rats in a sex-dependent manner
AbstractAn adverse environment in early life is often associated with dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis and higher rates of mood disorders in adulthood. In rats, exposure to social stress during pregnancy results in hyperactive HPA axis responses to stress in the adult offspring and heightened anxiety behavior in the males, but not the females. Here we tested whether, without further intervention, the effects of prenatal stress (PNS) in the first filial generation (F1) are transmitted to the F2 generation via the maternal line. F1 control and PNS female rats were mated with control males and housed under non-stress conditions throughout pregnancy. HPA axis responses to acute stress, anxiety- and depressive-like behavior were assessed in the adult F2 offspring.ACTH and corticosterone responses to an acute stressor were markedly enhanced in F2 PNS females compared with controls. This was associated with greater corticotropin releasing hormone (Crh) mRNA expression in the paraventricular nucleus and reduced hippocampal glucocorticoid (Gr) and mineralocorticoid receptor (Mr) mRNA expression. Conversely, in the F2 PNS males, HPA axis responses to acute stress were attenuated and hippocampal Gr mRNA expression was greater compared with controls.F2 PNS males exhibited heightened anxiety-like behavior (light-dark box and elevated plus maze) compared with F2 control males. Anxiety-like behavior did not differ between F2 control and PNS females during metestrus/diestrus, however at proestrus/estrus, F2 control females displayed a reduction in anxiety-like behavior, but this effect was not observed in the F2 PNS females. Heightened anxiety in the F2 PNS males was associated with greater Crh mRNA expression in the central nucleus of the amygdala compared with controls. Moreover, Crh receptor-1 (Crhr1) mRNA expression was significantly increased, whereas Crhr2 mRNA was significantly decreased in discrete regions of the amygdala in F2 PNS males compared with controls, with no differences in the F2 females. No differences in depressive-like behavior (sucrose preference or forced swim test) were observed in either sex. In conclusion, the effects of maternal stress during pregnancy on HPA axis regulation and anxiety-like behavior can be transmitted to future generations in a sex-dependent manner. These data have implications for human neuropsychiatric disorders with developmental origins
Fetal brain 11β-hydroxysteroid dehydrogenase type 2 selectively determines programming of adult depressive-like behaviors and cognitive function, but not anxiety behaviors in male mice
Stress or elevated glucocorticoids during sensitive windows of fetal development increase the risk of neuropsychiatric disorders in adult rodents and humans, a phenomenon known as glucocorticoid programming. 11β-Hydroxysteroid dehydrogenase type 2 (11β-HSD2), which catalyses rapid inactivation of glucocorticoids in the placenta, controls access of maternal glucocorticoids to the fetal compartment, placing it in a key position to modulate glucocorticoid programming of behavior. However, the importance of the high expression of 11β-HSD2 within the midgestational fetal brain is unknown. To examine this, a brain-specific knockout of 11β-HSD2 (HSD2BKO) was generated and compared to wild-type littermates. HSD2BKO have markedly diminished fetal brain 11β-HSD2, but intact fetal body and placental 11β-HSD2 and normal fetal and placental growth. Despite normal fetal plasma corticosterone, HSD2BKO exhibit elevated fetal brain corticosterone levels at midgestation. As adults, HSD2BKO show depressive-like behavior and have cognitive impairments. However, unlike complete feto-placental deficiency, HSD2BKO show no anxiety-like behavioral deficits. The clear mechanistic separation of the programmed components of depression and cognition from anxiety implies distinct mechanisms of pathogenesis, affording potential opportunities for stratified interventions
The porous cell: monastic ritual, intentional living, and varieties of knowledge in American Contemplative Christianity
Based on three and a half years of research among semi-cloistered Christian monastics and a dispersed network of non-monastic Christian contemplatives around the United States, this study shows how religious practitioners in both settings combined social action and intentional living with intellectual study and intensive contemplative practices in an effort to modify their ways of knowing, sensing, and experiencing the world. It explores the interplay of social diversity and cohesiveness in pluralistic society and the relationship of agency and habitus in practitioners' conscious attempts at spiritual transformation. Organized by the metaphor of a seeker journeying towards the inner chambers of a monastic chapel, The Porous Cell uses innovative "intersubjective" fieldwork methods to study these opaque interiorized, often silent communities, in order to show how solitude, chant, contemplation, attention, and a paradoxical capacity to combine active ritual with intentional "unknowing" develop and hone a powerful sense of communion and foster a unitive state in relationship to "life in the world." Cloistered monastics encouraged a commitment to ancient Christian ideals and practices, but both they and dispersed non-monastics enriched the movement's character by including aspects of other religious traditions.
Partially inspired by Fredrik Barth's anthropology of knowledge, the thesis develops a novel theory of clines of multiple epistemologies, which include intellectual, experiential, performative, and contemplative knowledges, as well as the notion of "unknowing." This model of variable knowledges (both conscious and "embodied") shows how contemplative communities can be diverse and yet retain considerable cohesiveness and stability.
American Christian contemplatives' ability to fuse so many spheres of knowledge and to live contemplatively challenges the often taken-for-granted segregation of the religious, secular, sacred, and profane in the modern world. Further, this study contributes to the anthropologies of perception, silence, embodiment, and experience, and to the anthropology and epistemology of Christianity. It extends American ethnography by its use of new methods for studying silence and performance, and by focusing on a highly educated and mostly urban, professional, Euro-American community (in both its geographically-situated and "non-gathered," network-based guises) which is rarely the subject of ethnographic research and is often assumed to be the demographic most likely to reject religion.2022-08-01T00:00:00
Forming “Mediators and Instruments of Grace”: The Emerging Role of Monastics in Teaching Contemplative Ambiguity and Practice to the Laity
Drawing from long-term ethnographic research with a global network of contemplative Christians, this paper discusses an emerging teaching role for North American monasteries as the numbers of avowed religious decline. Since the Trappist community of St. Joseph’s Abbey in Spencer, Massachusetts, first developed the Christian meditation technique called Centering Prayer in the 1970s, monks and nuns have increasingly become teachers, models, and stabilizers of non-monastic practitioners who attempt to transform their ways of being and thinking towards monastic-inspired sensibilities. Their guidance includes the use of face-to-face, literary, and virtual means to teach methods of contemplative intersubjectivity and a commitment to lives based on service, hospitality, and humility, as well as on study and formalized rites. The paper focuses on non-monastics’ strong attraction to monastic teachings on ambiguity as a source of creativity and wonder in uncertain times, as practiced through a combination of cataphatic and apophatic ritual, including Centering Prayer. The number of monastic postulants continues to falter, yet a much larger, “non-gathered” community of non-monastic oblates and neo-monastic contemplatives has grown increasingly reliant on monastics to help provide alternatives. The rising interdependence of monastics and non-monastics may become the basis of a transformation of Christian monasticism and a new concept of religious community.Arts, Faculty ofAnthropology, Department ofReviewedFacult
Cardenolides in nectar may be more than a consequence of allocation to other plant parts: a phylogenetic study of Asclepias
The primary function of secondary plant metabolites is thought to be defence against herbivores. The frequent occurrence of these same noxious compounds in floral nectar, which functions primarily to attract pollinators, has been seen as paradoxical. Although these compounds may have an adaptive purpose in nectar, they may also occur as a nonadaptive consequence of chemical defence in other plant parts. If nectar chemistry reflects physiological constraints or passive leakage from other tissues, we expect that the identity and relative concentration of nectar cardenolides to be correlated with those of other plant parts; in contrast, discordant distributions of compounds in nectar and other tissues may suggest adaptive roles in nectar. We compared the concentrations and identities of cardenolides in the nectar, leaves and flowers of 12 species from a monophyletic clade of Asclepias. To measure putative toxicity of nectar cardenolides, we then examined the effects of a standard cardenolide (digoxin) on the behaviour of bumblebees, a common generalist pollinator of Asclepias. We found that the average cardenolide concentrations in nectar, leaves and flowers of the 12 Asclepias species were positively correlated as predicted by nonadaptive hypotheses. However, significant differences in the identities and concentrations of individual cardenolides between nectar and leaves suggest that the production or allocation of cardenolides may be independently regulated at each plant part. In addition, cardenolide concentrations in leaves and nectar exhibited no phylogenetic signal. Surprisingly, bumblebees did not demonstrate an aversion to digoxin-rich nectar, which may indicate that nectar cardenolides have little effect on pollination. Although the idea that discordant patterns of secondary metabolites across tissue types may signal adaptive functions is attractive, there is evidence to suggest constraint contributes to nectar secondary chemistry. Further work testing the ecological impacts of such patterns will be critical in determining the functional significance of nectar cardenolide