Everyday limits to adaptation

Adaptation to climate change, in terms of both academic and policy debates, has been treated predominantly as a local issue. This scalar focus points towards local agency as well as the contested responsibilisation of local actors and potential disconnects with higher-level dynamics. While there are growing calls for individuals to take charge of their own lives against mounting climatic forces, little is known about the day-to-day actions people take, the many hurdles, barriers, and limits they encounter in their adaptation choices, and the trade-offs they consider envisaging the future. To address this gap, this article draws on 80+ interviews with urban and rural residents in Western Australia to offer a nuanced analysis of everyday climate adaptation and its limits. Our findings demonstrate that participants are facing significant adaptation barriers and that, for many, these barriers already constitute limits to what they can do to protect what they value most. They also make visible how gender, age, and socioeconomic status shape individual preferences, choices, and impediments, revealing compounding layers of disadvantage and differential vulnerability. We argue that slow and reflexive research is needed to understand what adaptation limits matter and to whom and identify opportunities to harness and support local action. Only then will we be able to surmount preconceived neoliberal ideals of the self-sufficient, resilient subject, engage meaningfully with ontological pluralism, and contribute to the re-politicisation of adaptation decision making.

Natural History of Retinal Degeneration in Ovine Models of CLN5 and CLN6 Neuronal Ceroid Lipofuscinoses

Neuronal ceroid lipofuscinoses (NCL; Batten disease) are a group of inherited neurodegenerative diseases with a common set of symptoms including cognitive and motor decline and vision loss. Naturally occurring sheep models of CLN5 and CLN6 disease display the key clinical features of NCL, including a progressive loss of vision. We assessed retinal histology, inflammation, and lysosomal storage accumulation in CLN5 affected (CLN5−/−) and CLN6 affected (CLN6−/−) sheep eyes and age-matched controls at 3, 6, 12, and 18 months of age to determine the onset and progression of retinal pathology in NCL sheep. The retina of CLN5−/− sheep shows progressive atrophy of the outer retinal layers, widespread inflammation, and accumulation of lysosomal storage in retinal ganglion cells late in disease. In contrast, CLN6−/− retina shows significant atrophy of all retinal layers, progressive inflammation, and earlier accumulation of lysosomal storage. This study has highlighted the differential vulnerability of retinal layers and the time course of retinal atrophy in two distinct models of NCL disease. This data will be valuable in determining potential targets for ocular therapies and the optimal timing of these therapies for protection from retinal dysfunction and degeneration in NCL.

Stressful Life Events, Differential Vulnerability, and Depressive Symptoms: Critique and New Evidence

Depressive symptoms are disproportionately high among women and less educated individuals. One mechanism proposed to explain this is the differential vulnerability hypothesis—that these groups experience particularly strong increases in symptoms in response to stressful life events. We identify limitations to prior work and present evidence from a new approach to life stress research using the UK Household Longitudinal Study. Preliminarily, we replicate prior findings of differential vulnerability in between-individual models. Harnessing repeated measures, however, we show that apparent findings of differential vulnerability by both sex and education are artifacts of confounding. Men and women experience similar average increases in depressive symptoms after stressful life events. One exception is tentative evidence for a stronger association among women for events occurring to others in the household. We term this the “female vulnerability to network events” hypothesis and discuss with reference to Kessler and McLeod’s related “cost of caring” hypothesis.

The essential role of transcription factor Pitx3 in preventing mesodiencephalic dopaminergic neurodegeneration and maintaining neuronal subtype identities during aging

Pituitary homeobox 3 (Pitx3) is required for the terminal differentiation of nigrostriatal dopaminergic neurons during neuronal development. However, whether Pitx3 contributes to the normal physiological function and cell-type identity of adult neurons remains unknown. To explore the role of Pitx3 in maintaining mature neurons, we selectively deleted Pitx3 in the mesodiencephalic dopaminergic (mdDA) neurons of Pitx3fl/fl/DATCreERT2 bigenic mice using a tamoxifen inducible CreERT2/loxp gene-targeting system. Pitx3fl/fl/DATCreERT2 mice developed age-dependent progressive motor deficits, concomitant with a rapid reduction of striatal dopamine (DA) content and a profound loss of mdDA neurons in the substantia nigra pars compacta (SNc) but not in the adjacent ventral tegmental area (VTA), recapitulating the canonical neuropathological features of Parkinson’s disease (PD). Mechanistic studies showed that Pitx3-deficiency significantly increased the number of cleaved caspase-3+ cells in SNc, which likely underwent neurodegeneration. Meanwhile, the vulnerability of SNc mdDA neurons was increased in Pitx3fl/fl/DATCreERT2 mice, as indicated by an early decline in glial cell line-derived neurotrophic factor (GDNF) and aldehyde dehydrogenase 1a1 (Aldh1a1) levels. Noticeably, somatic accumulation of α-synuclein (α-syn) was also significantly increased in the Pitx3-deficient neurons. Together, our data demonstrate that the loss of Pitx3 in fully differentiated mdDA neurons results in progressive neurodegeneration, indicating the importance of the Pitx3 gene in adult neuronal survival. Our findings also suggest that distinct Pitx3-dependent pathways exist in SNc and VTA mdDA neurons, correlating with the differential vulnerability of SNc and VTA mdDA neurons in the absence of Pitx3.

Post-trauma behavioral phenotype predicts vulnerability to fear relapse after extinction

Current treatments for trauma-related disorders remain ineffective for many patients. Here, we modeled interindividual differences in post-therapy fear relapse with a novel ethologically relevant trauma recovery paradigm. After traumatic fear conditioning, rats underwent fear extinction while foraging in a large enriched arena, permitting the expression of a wide spectrum of behaviors, assessed by an automated pipeline. This multidimensional behavioral assessment revealed that post-conditioning fear response profiles clustered into two groups, respectively characterized by active vs. passive fear responses. After trauma, some animals expressed fear by freezing, while others darted, as if fleeing from danger. Remarkably, belonging to the darters or freezers group predicted differential vulnerability to fear relapse after extinction. Moreover, genome-wide transcriptional profiling revealed that these groups differentially regulated specific sets of genes, some of which have previously been implicated in anxiety and trauma-related disorders. Our results suggest that post-trauma behavioral phenotypes and the associated epigenetic landscapes can serve as markers of fear relapse susceptibility, and thus may be instrumental for future development of more effective treatments for psychiatric patients.

Genetic Markers of Differential Vulnerability to Sleep Loss in Adults

In this review, we discuss reports of genotype-dependent interindividual differences in phenotypic neurobehavioral responses to total sleep deprivation or sleep restriction. We highlight the importance of using the candidate gene approach to further elucidate differential resilience and vulnerability to sleep deprivation in humans, although we acknowledge that other omics techniques and genome-wide association studies can also offer insights into biomarkers of such vulnerability. Specifically, we discuss polymorphisms in adenosinergic genes (ADA and ADORA2A), core circadian clock genes (BHLHE41/DEC2 and PER3), genes related to cognitive development and functioning (BDNF and COMT), dopaminergic genes (DRD2 and DAT), and immune and clearance genes (AQP4, DQB1*0602, and TNFα) as potential genetic indicators of differential vulnerability to deficits induced by sleep loss. Additionally, we review the efficacy of several countermeasures for the neurobehavioral impairments induced by sleep loss, including banking sleep, recovery sleep, caffeine, and naps. The discovery of reliable, novel genetic markers of differential vulnerability to sleep loss has critical implications for future research involving predictors, countermeasures, and treatments in the field of sleep and circadian science.