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Characterization and Isolation of Mouse Primary Microglia by Density Gradient Centrifugation
Published on: February 16, 2018
Microglia Regulate Neuronal Circuits in Homeostatic and High-Fat Diet-Induced Inflammatory Conditions
Xiao-Lan Wang1, Lianjian Li2,3
1Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Abstract:
Microglia are brain resident macrophages, which actively survey the surrounding microenvironment and promote tissue homeostasis under physiological conditions. During this process, microglia participate in synaptic remodeling, neurogenesis, elimination of unwanted neurons and cellular debris. The complex interplay between microglia and neurons drives the formation of functional neuronal connections and maintains an optimal neural network. However, activation of microglia induced by chronic inflammation increases synaptic phagocytosis and leads to neuronal impairment or death. Microglial dysfunction is implicated in almost all brain diseases and leads to long-lasting functional deficiency, such as hippocampus-related cognitive decline and hypothalamus-associated energy imbalance (i.e., obesity). High-fat diet (HFD) consumption triggers mediobasal hypothalamic microglial activation and inflammation. Moreover, HFD-induced inflammation results in cognitive deficits by triggering hippocampal microglial activation. Here, we have summarized the current knowledge of microglial characteristics and biological functions and also reviewed the molecular mechanism of microglia in shaping neural circuitries mainly related to cognition and energy balance in homeostatic and diet-induced inflammatory conditions.
Insights
Microglia, the brain's immune cells, maintain neural networks but can impair cognition and energy balance when inflamed by a high-fat diet (HFD). Understanding microglial function is key to addressing diet-induced brain dysfunction.
Area of Science:
- Neuroscience
- Immunology
- Metabolism
Background:
- Microglia are essential brain-resident macrophages involved in synaptic remodeling and tissue homeostasis.
- Their dysfunction, driven by chronic inflammation, contributes to neurological disorders like cognitive decline and obesity.
- High-fat diet (HFD) consumption activates hypothalamic and hippocampal microglia, leading to inflammation and deficits.
Purpose of the Study:
- To review microglial characteristics and biological functions.
- To explore the molecular mechanisms of microglia in neural circuitry.
- To understand microglia's role in cognition and energy balance under homeostatic and inflammatory conditions.
Main Methods:
- Literature review of microglial biology.
- Analysis of molecular mechanisms in neural circuit shaping.
- Synthesis of data on diet-induced inflammation and microglial activation.
Main Results:
- Microglia play a dual role: maintaining homeostasis and causing impairment when activated.
- HFD triggers microglial activation in the hypothalamus and hippocampus.
- This activation leads to inflammation, synaptic changes, and associated functional deficits.
Conclusions:
- Microglial activation and dysfunction are central to HFD-induced cognitive and metabolic disorders.
- Targeting microglial pathways may offer therapeutic strategies for diet-related brain diseases.
- Further research into microglial mechanisms is crucial for understanding brain health and disease.
