Elise J. Heesbeen , Elisabeth Y. Bijlsma , Tristan A. Risseeuw , Ellen V.S. Hessel , Lucianne Groenink
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引用次数: 0
Abstract
Background
The pathophysiology of several neurodegenerative and neuropsychiatric disorders is linked to an altered immune system. However, it is often unclear how the immune system specifically affects these disorders since neuroimmune interactions are very complex. In this paper, we introduce an adjusted version of the adverse outcome pathway (AOP) approach from toxicology to the field of neuroimmunology. A review of the effect of TNF-α on fear learning deficits is used as a worked example to demonstrate how an AOP approach can help identify gaps of knowledge and crucial steps in the pathophysiology of neuroimmunological disorders.
Methods
The AOP was constructed in five steps. First, the adverse outcome was formulated clearly and specifically. Second, the link between the molecular initiating event and the adverse outcome was established with a preliminary literature search in the Medline database. Third, a systematic literature search was performed in which we identified 95 relevant articles. Fourth, the main biological processes and relevant key events were identified. Fifth, the links between key events were determined and an AOP network was constructed.
Results
We identified three pathways through which TNF-α may affect fear learning. First, TNF-α receptor activation increases NF-κB levels which increases oxidative stress levels and reduces the activity of glutamate transporters. This alters the synaptic plasticity which is associated with impaired fear acquisition, consolidation, and fear extinction. Second, activation of TNF-α receptors increases the expression and capacity of the serotonin transporter which is linked to impaired fear acquisition, expression, and extinction. Third, TNF-α receptor 1 activation can induce necroptosis, leading to neuroinflammation which is linked to fear learning deficits.
Conclusion
To successfully apply the AOP approach in neuroimmunology we recommend defining adverse outcomes more precisely, establishing stronger connections between key events from various biological processes, incorporating feedforward and feedback loops, and identifying more mechanistic knowledge in later key events. These adjustments are needed to map the complex processes within the field of neuroimmunology and to identify gaps of knowledge.
期刊介绍:
Established in 1987, Brain, Behavior, and Immunity proudly serves as the official journal of the Psychoneuroimmunology Research Society (PNIRS). This pioneering journal is dedicated to publishing peer-reviewed basic, experimental, and clinical studies that explore the intricate interactions among behavioral, neural, endocrine, and immune systems in both humans and animals.
As an international and interdisciplinary platform, Brain, Behavior, and Immunity focuses on original research spanning neuroscience, immunology, integrative physiology, behavioral biology, psychiatry, psychology, and clinical medicine. The journal is inclusive of research conducted at various levels, including molecular, cellular, social, and whole organism perspectives. With a commitment to efficiency, the journal facilitates online submission and review, ensuring timely publication of experimental results. Manuscripts typically undergo peer review and are returned to authors within 30 days of submission. It's worth noting that Brain, Behavior, and Immunity, published eight times a year, does not impose submission fees or page charges, fostering an open and accessible platform for scientific discourse.