Role of the habenulo-interpeduncular system in the neurodevelopmental basis of susceptibility and resilience to stress-induced anxiety

Experiencing stress during sensitive periods of brain development has a major impact on how individuals cope with later stress. Although many become more prone to develop anxiety or depression, some appear resilient. The mechanisms underlying these differences are unknown. Key answers may lie in how genetic and environmental stressors interact to shape the circuits controlling emotions. Here we studied the role of the habenulo-interpeducuncular system (HIPS), a critical node of reward circuits, in early stress-induced anxiety. We found that a subcircuit of this system, characterized by Otx2 expression, is particularly responsive to chronic stress during puberty, which induces HIPS hypersensitivity to later stress and susceptibility to develop anxiety. We further show that Otx2 deletion restricted to the HIPS counteracts these effects of stress. Together, these results demonstrate that Otx2 and stress interact, around puberty, to shape the HIPS stress-response, revealed here as a key modulator of susceptibility/resilience to develop anxiety.

Role of the habenulo-interpeduncular system in the neurodevelopmental basis of susceptibility and resilience to stressinduced anxiety

Experiencing stress during sensitive periods of brain development has a major impact on how individuals cope with later stress. Although many become more prone to develop anxiety or depression, some appear resilient. The mechanisms underlying these differences are unknown. Key answers may lie in how genetic and environmental stressors interact to shape the circuits controlling emotions. Here we studied the role of the habenulo-interpeducuncular system (HIPS), a critical node of reward circuits, in early stress-induced anxiety. We found that a subcircuit of this system, characterized by Otx2 expression, is particularly responsive to chronic stress during puberty, which induces HIPS hypersensitivity to later stress and susceptibility to develop anxiety. We further show that Otx2 deletion restricted to the HIPS counteracts these effects of stress. Together, these results demonstrate that Otx2 and stress interact, around puberty, to shape the HIPS stress-response, revealed here as a key modulator of susceptibility/resilience to develop anxiety.

Evaluating fixed-film nitrification systems in autotrophic mode: Enhanced biomass retention does not improve bioreactor performance during alkalinity induced stress

Use of fixed-film systems has shown promise towards improving the process stability of biological nitrogen removal (BNR). It allows for biofilm formation, which can offer enhanced resilience to environmental stressors...

TOXICITY MEDIATED OXIDATIVE STRESS AND ITS MITIGATION STRATEGIES IN CROP PLANTS

Oxidative stress occurs in plant due to various environmental stressors like drought, high temperature, pathogen invasion, heavy metals, pesticides etc. when plant faces these conditions, reactive oxygen species (ROS) are produced in the chloroplast, mitochondria, plasma membrane, peroxisomes, ER and cell wall due to the leakage of electrons. Depending upon its concentration the role of ROS is decided if less then it will act as a signaling molecule but if in excess it will damage the cellular machinery of plants as the production of species like free radicals would take place. Though to combat these stress plants have antioxidant defense machinery which include enzymatic and non- enzymatic which lower down the level of ROS. Through genetic engineering more tolerant plants are produced which include modification of key genes like transcription factors. In this review article the molecular physiology of plants is discussed where in the factors contributing to stress including biotic and abiotic factors and various mitigation strategies.

Considering variance in pollinator responses to stressors can reveal potential for resilience

Environmental stressors have sublethal consequences on animals, often affecting the mean of phenotypic traits in a population. However, potential effects on variance are poorly understood. Since phenotypic variance is the basis for adaptation, any influence of stressors may have important implications for population resilience. Here we explored this possibility in insect pollinators by analysing raw datasets from 24 studies (6,913 bees) in which individuals were first exposed to stressors and then tested for cognitive tasks. While all types of stressors decreased the mean cognitive performance of bees, their effect on variance was complex. Focusing on 15 pesticide studies, we found that the dose and the mode of exposure to stressors were critical. At low pesticide doses, cognitive variance decreased following chronic exposures but not for acute exposures. Acute exposure to low doses thus seems less damaging at the population level. In all cases however, the variance decreased with increasing doses. Policy implications: Current guidelines for the authorization of plant protection products on the European market prioritize acute over chronic toxicity assessments on non-target organisms. By overlooking the consequences of a chronic exposure, regulatory authorities may register new products that are harmful to bee populations. Our findings thus call for more research on stress-induced phenotypic variance and its incorporation to policy guidelines to help identify levels and modes of exposure animals can cope with.

Common Environmental Pollutants Negatively Affect Development and Regeneration in the Sea Anemone Nematostella vectensis Holobiont

The anthozoan sea anemone Nematostella vectensis belongs to the phylum of cnidarians which also includes jellyfish and corals. Nematostella are native to United States East Coast marsh lands, where they constantly adapt to changes in salinity, temperature, oxygen concentration and pH. Its natural ability to continually acclimate to changing environments coupled with its genetic tractability render Nematostella a powerful model organism in which to study the effects of common pollutants on the natural development of these animals. Potassium nitrate, commonly used in fertilizers, and Phthalates, a component of plastics are frequent environmental stressors found in coastal and marsh waters. Here we present data showing how early exposure to these pollutants lead to dramatic defects in development of the embryos and eventual mortality possibly due to defects in feeding ability. Additionally, we examined the microbiome of the animals and identified shifts in the microbial community that correlated with the type of water that was used to grow the animals, and with their exposure to pollutants.