No abstract

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of unknown cause. Absence of specific targets and biomarkers compromise the development of new therapeutic strategies and of innovative tools to stratify patients and assess their responses to treatment. Here, we investigate changes in neuroprotective-neuroinflammatory actions in the spinal cord of SOD1 mice, at presymptomatic and symptomatic stages to identify stage-specific biomarkers and potential targets. Results showed that in the presymptomatic stage, there are alterations in both astrocytes and microglia, which comprise decreased expression of GFAP and S100B and upregulation of GLT-1, as well as reduced expression of CD11b, M2-phenotype markers, and a set of inflammatory mediators. Reduced levels of Connexin-43, Pannexin-1, CCL21, and CX3CL1 further indicate the existence of a compromised intercellular communication. In contrast, in the symptomatic stage, increased markers of inflammation became evident, such as NF-κB/Nlrp3-inflammasome, Iba1, pro-inflammatory cytokines, and M1-polarizion markers, together with a decreased expression of M2-phenotypic markers. We also observed upregulation of the CX3CL1-CX3CR1 axis, Connexin-43, Pannexin-1, and of microRNAs (miR)-124, miR-125b, miR-146a and miR-21. Reduced motor neuron number and presence of reactive astrocytes with decreased GFAP, GLT-1, and GLAST further characterized this inflammatory stage. Interestingly, upregulation of miR-155 and downregulation of MFG-E8 appear as consistent biomarkers of both presymptomatic and symptomatic stages. We hypothesize that downregulated cellular interplay at the early stages may represent neuroprotective mechanisms against inflammation, SOD1 aggregation, and ALS onset. The present study identified a set of inflamma-miRNAs, NLRP3-inflammasome, HMGB1, CX3CL1-CX3CR1, Connexin-43, and Pannexin-1 as emerging candidates and promising pharmacological targets that may represent potential neuroprotective strategies in ALS therapy.

Advances in ocean observing technologies and modeling provide the capacity to revolutionize the management of living marine resources. While traditional fisheries management approaches like single-species stock assessments are still common, a global effort is underway to adopt ecosystem-based fisheries management (EBFM) approaches. These approaches consider changes in the physical environment and interactions between ecosystem elements, including human uses, holistically. For example, integrated ecosystem assessments aim to synthesize a suite of observations (physical, biological, socioeconomic) and modeling platforms [ocean circulation models, ecological models, short-term forecasts, management strategy evaluations (MSEs)] to assess the current status and recent and future trends of ecosystem components. This information provides guidance for better management strategies. A common thread in EBFM approaches is the need for high-quality observations of ocean conditions, at Frontiers in Marine Science | www.frontiersin.org 1 September 2019 | Volume 6 | Article 550 Schmidt et al. Ocean Observation Futures for Fisheriesscales that resolve critical physical-biological processes and are timely for management needs. Here we explore options for a future observing system that meets the needs of EBFM by (i) identifying observing needs for different user groups, (ii) reviewing relevant datasets and existing technologies, (iii) showcasing regional case studies, and (iv) recommending observational approaches required to implement EBFM. We recommend linking ocean observing within the context of Global Ocean Observing System (GOOS) and other regional ocean observing efforts with fisheries observations, new forecasting methods, and capacity development, in a comprehensive ocean observing framework.

Many seahorse species are already threatened worldwide, and we do not know how they will endure an additional threat as climate change. Our results show that adult seahorses (Hippocampus guttulatus) seem to be relatively well prepared to face future changes in ocean temperature, but not the combined effect of warming and acidification.

Despite the long evolutionary history of this group, the challenges brought by the Anthropocene have been inflicting an extensive pressure over sharks and their relatives. Overexploitation has been driving a worldwide decline in elasmobranch populations, and rapid environmental change, triggered by anthropogenic activities, may further test this group's resilience. In this context, we searched the literature for peer-reviewed studies featuring a sustained (>24 h) and controlled exposure of elasmobranch species to warming, acidification, and/or deoxygenation: three of the most pressing symptoms of change in the ocean. In a standardized comparative framework, we conducted an array of mixed-model meta-analyses (based on 368 control-treatment contrasts from 53 studies) to evaluate the effects of these factors and their combination as experimental treatments. We further compared these effects across different attributes (lineages, climates, lifestyles, reproductive modes, and life stages) and assessed the direction of impact over a comprehensive set of biological responses (survival, development, growth, aerobic metabolism, anaerobic metabolism, oxygen transport, feeding, behavior, acid-base status, thermal tolerance, hypoxia tolerance, and cell stress). Based on the present findings, warming appears as the most influential factor, with clear directional effects, namely decreasing development time and increasing aerobic metabolism, feeding, and thermal tolerance. While warming influence was pervasive across attributes, acidification effects appear to be more context-specific, with no perceivable directional trends across biological responses apart from the necessary to achieve acid-base balance. Meanwhile, despite its potential for steep impacts, deoxygenation has been the most neglected factor, with data paucity ultimately precluding sound conclusions. Likewise, the implementation of multi-factor treatments has been mostly restricted to the combination of warming and acidification, with effects approximately matching those of warming. Despite considerable progress over recent years, research regarding the impact of these drivers on elasmobranchs lags behind other taxa, with more research required to disentangle many of the observed effects. Given the current levels of extinction risk and the quick pace of global change, it is further crucial that we integrate the knowledge accumulated through different scientific approaches into a holistic perspective to better understand how this group may fare in a changing ocean.

Highlights d BHLHA9 function in C-LTMRs is sexually dimorphic d Loss of BHLHA9 impaired formalin-evoked pain selectively in males d BHLHA9 in C-LTMRs is required for fine discriminative aspects of temperature in males d Loss of BHLHA9 non-cell-autonomously impairs ionotropic GABAergic signaling

No abstract

Sharks have maintained a key role in marine food webs for 400 million years and across varying physicochemical contexts, suggesting plasticity to environmental change. In this study, we investigated the biochemical effects of ocean acidification (OA) levels predicted for 2100 (pCO ~ 900 μatm) on newly hatched tropical whitespotted bamboo sharks (Chiloscyllium plagiosum). Specifically, we measured lipid, protein, and DNA damage levels, as well as changes in the activity of antioxidant enzymes and non-enzymatic ROS scavengers in juvenile sharks exposed to elevated CO for 50 days following hatching. Moreover, we also assessed the secondary oxidative stress response, i.e., heat shock response and ubiquitin levels. Newly hatched sharks appear to cope with OA-related stress through a range of tissue-specific biochemical strategies, specifically through the action of antioxidant enzymatic compounds. Our findings suggest that ROS-scavenging molecules, rather than complex enzymatic proteins, provide an effective defense mechanism in dealing with OA-elicited ROS formation. We argue that sharks' ancient antioxidant system, strongly based on non-enzymatic antioxidants (e.g., urea), may provide them with resilience towards OA, potentially beyond the tolerance of more recently evolved species, i.e., teleosts. Nevertheless, previous research has provided evidence of detrimental effects of OA (interacting with other climate-related stressors) on some aspects of shark biology. Moreover, given that long-term acclimation and adaptive potential to rapid environmental changes are yet experimentally unaccounted for, future research is warranted to accurately predict shark physiological performance under future ocean conditions.