D-beta-hydroxybutyrate exhibits protective effects against microglia activation in lipopolysaccharide-treated mice and BV-2 cells

AbstractMicroglia activation is the key player in neuro-inflammation, which is the central process of neuro-disorders. The protective effects of D-beta-hydroxybutyrate (BHB) against microglia activation were evaluated in lipopolysaccharide (LPS)-treated mice and BV-2 cells. Behavioral test, morphological change and immunofluorescence of microglia marker ionizing calcium-binding adaptor molecule 1 (IBA-1) in the hippocampus, and the generation of inflammatory interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), and protective brain-derived neurotrophic factor (BDNF) and transforming growth factor-β (TGF-β) in the brain, were measured in LPS and/or BHB treated mice. In addition, the effects of BHB on the generation of IL-6, TNF-α, BDNF and TGF-β, and reactive oxygen species (ROS) level were detected in LPS-stimulated BV-2 cells. We found that BHB treatments attenuated behavioral abnormality of LPS-treated mice and reduced the number of IBA-1-positive cells with attenuation of cell morphological changes in the hippocampus. Meanwhile, BHB inhibited IL-6 and TNF-α generations; but promoted BDNF and TGF-β generations in the brain in LPS-treated mice. Furthermore, BHB concentration-dependently inhibited IL-6 and TNF-α generations, promoted BDNF and TGF-β generations, and reduced the level of reactive oxygen species with attenuation of cellular changes in LPS-stimulated BV-2 cells. In conclusion, BHB exhibits protective effects against microglia activation in LPS-treated mice and BV-2 cells, antagonizing neuro-inflammation.