NEUROINFLAMMATION MECHANISMS, CLINICAL IMPLICATIONS, AND THERAPEUTIC APPROACHES

neuroinflamationkapak

UNDERSTANDING NEUROINFLAMMATION

Çağla Şişman1
Ufuk Emre Toprak2

1İstanbul Training and Research Hospital, Department of Neurology, İstanbul, Türkiye
2İstanbul Training and Research Hospital, Department of Neurology, İstanbul, Türkiye

Şişman Ç, Toprak UE. Understanding Neuroinflammation. In: Şahin Ş editor. Neuroinflammation: Mechanisms, Clinical Implications, and Therapeutic Approaches. 1st ed. Ankara: Türkiye Klinikleri; 2025. p.1-10.

ABSTRACT

Neuroinflammation is defined as an inflammatory response occurring in the structures of the nervous system. This process, which develops in the brain and spinal cord, is a biological reaction initiated by the central nervous system to protect itself from harmful stimuli and to prevent or limit potential tissue damage. Neuroinflammation is shaped by the interaction of glial cells, endothelial cells, and peripheral immune cells. During this process, inflammatory mediators such as cytokines, chemokines, and reactive oxygen radicals are produced. Although this response initially serves as a protective mechanism, if it becomes excessive or chronic, it can lead to impairments in nervous system functions.

The severity of neuroinflammation varies depending on the intensity, duration, and nature of the stimulus. Inflammation can lead to the accumulation of immune cells in the tissue, tissue damage, and cell death. While this process aims to protect neural cells, prolonged or excessive activation of the immune system may contribute to the development of depression, cognitive disorders, and neurological diseases. Studies in recent years have supported the view that chronic neuroinflammation plays a significant role in neurological conditions such as Alzheimer Disease (AD), Parkinson Disease (PD), and Multiple Sclerosis (MS).

Neuroinflammation is necessary for neuronal protection and the regulation of synaptic plasticity. However, when this process is persistent and at high levels, it can lead to damage in synaptic connections. Therefore, neuroinflammation is a dual-faceted condition that can be both protective and harmful. The adverse effects of neuroinflammation can generally be maintained within a balanced state referred to as “euinflammation.” This article thoroughly examines the definition, development, and impact of neuroinflammation on neurological diseases.

Keywords: Neuroinflammation; Inflammation; Microglia; Glymphatic system; Cytokines; Immunity; Neurodegeneration; Gut-brain axis; Blood-brain barrier

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