Understanding the role of microglia and inflammatory biomarkers in stress-associated neuropsychiatric disorders

Li Tian, Ph.D.


Research Professor in Neuroimmunology, Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Estonia;

Adjunct Professor, Neuroscience Center, University of Helsinki, Finland



Background My presentation explores certain (micro)glia-enriched immune genes for their potential contribution to psychiatric disorders as genetic biomarkers and the underlying mechanisms. Microglia are extremely sensitive to stress and their ‘activation’ has been regarded as exacerbating stress response.


Method We have explored the effects of chronic restraint stress (CRS) on microglial physiological functions in adult male C57BL/6 and CX3CR1KO mice. Alongside behavioral tests of CRS-treated animals, microglial functions in the hippocampus (HPC), infralimbic cortex (IL), prefrontal cortex (PFC) and amygdala (AMYG), as well as control areas (the secondary motor cortex M2 or somatosensory cortex SSC) were studied by various laboratory methods. 


Result We found that CRS strengthened social dominance and spatial learning motivation. Meanwhile, microglia showed region-specific modifications of cell body volume and process ramification, reduced contacts with synaptic elements and accumulation of phagocytic debris in the IL and AMYG, and a decreased MHCII+ / CD206+ sub-populational ratio, particularly in the HPC, accompanied by upregulation of genes C3, Cd200r1 and Sgk1 but downregulation of P2ry12 in various regions.


Conclusion Overall, these findings identify adaptive changes in microglial function that may contribute to mediating the beneficial behavioral response to CRS.