Instituto de Neurociencia, Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
Laboratory of Stress Neurobiology, Centre for Integrative Neurobiology and Pathophysiology, Institute of Physiology, Faculty of Sciences, Universidad de Valparaíso, Valparaíso, Chile.
J Neurosci Res. 2021 Oct;99(10):2493-2510. doi: 10.1002/jnr.24902. Epub 2021 Jun 29.
Resilience to stress is the ability to quickly adapt to adversity. There is evidence that exposure to prolonged stress triggers neuroinflammation what produces individual differences in stress vulnerability. However, the relationship between stress resilience, neuroinflammation, and depressive-like behaviors remains unknown. The aim of this study was to analyze the long-term effects of social defeat stress (SDS) on neuroinflammation in the hippocampus and depressive-like behaviors. Male rats were subjected to the SDS paradigm. Social interaction was analyzed 1 and 2 weeks after ending the SDS to determine which animals were susceptible or resilient to stress. Neuroinflammation markers glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, and elevated membrane permeability in astrocytes and microglia, as well as depressive-like behaviors in the sucrose preference test and forced swim test were evaluated in all rats. One week after SDS, resilient rats increased their sucrose preference, and time spent in the floating behavior decreased in the forced swim test compared to susceptible rats. Surprisingly, resilient rats became susceptible to stress, and presented neuroinflammation 2 weeks after SDS. These findings suggest that SDS-induced hippocampal neuroinflammation persists in post-stress stages, regardless of whether rats were initially resilient or not. Our study opens a new approach to understanding the neurobiology of stress resilience.
抗压能力是指迅速适应逆境的能力。有证据表明，长期暴露于压力下会引发神经炎症，从而导致个体对压力的易感性存在差异。然而，压力适应能力、神经炎症和类似抑郁的行为之间的关系尚不清楚。本研究旨在分析社交挫败应激（SDS）对海马体神经炎症和类似抑郁的行为的长期影响。雄性大鼠接受 SDS 范式处理。SDS 结束后 1 周和 2 周分析社交互动，以确定哪些动物对压力敏感或有抗压能力。在所有大鼠中评估神经炎症标志物胶质纤维酸性蛋白、钙结合衔接分子 1、星形胶质细胞和小胶质细胞的膜通透性升高以及蔗糖偏好测试和强迫游泳测试中的类似抑郁行为。SDS 后 1 周，抗压大鼠增加了蔗糖偏好，而在强迫游泳测试中漂浮行为的时间减少。令人惊讶的是，抗压大鼠在 SDS 后 2 周变得对压力敏感，并出现了神经炎症。这些发现表明，SDS 诱导的海马体神经炎症在应激后阶段持续存在，无论大鼠最初是否具有抗压能力。我们的研究为理解压力适应能力的神经生物学提供了新的方法。
