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Updated: Apr 19, 2026
Mitochondrial Preparation from Microglia for Glycan Analysis
Published on: May 30, 2025
iTRAQ-based proteomic analysis of tetramethylpyrazine inhibition on lipopolysaccharide-induced microglial activation
Qiang-Hong Pu1, Jun-Lin He1, Ming-Jun Wu1
1Institute of Life Science and School of Public Health, Chongqing Medical University, Chongqing 400016, PR China.
Aims:
Neurodegenerative diseases are the leading cause of morbidity and mortality worldwide. Several studies have shown that tetramethylpyrazine (TMP) is an effective therapy for neurodegenerative diseases and that it acts by inhibiting the activation of microglial cells in response to inflammatory stimuli. However, the molecular mechanisms underlying the action of TMP remain unknown.
Main Methods:
Proteomic analysis was used to generate novel insights into the mechanism by which TMP inhibits microglial activation, and western blotting was used to validate candidate proteins.
Key Findings:
To identify candidate proteins affected by TMP in lipopolysaccharide-activated microglia, we performed proteomic analysis using iTRAQ labelling coupled with LC TRIPLE-TOF, and we identified 5187 unique proteins. Among these, 266 proteins were differentially expressed and considered putative candidate proteins. Protein annotation revealed that the differentially expressed proteins, such as inducible nitric oxide synthase (iNOS) and ERO1-like protein (ERO1L), might be involved in reducing cellular oxidation in response to stress. Ingenuity pathway analysis revealed that the differentially expressed proteins were involved in a variety of signalling pathways, including liver X receptor/retinoid X receptor (LXR/RXR) activation and the production of nitric oxide and reactive oxygen species in macrophages. Furthermore, one of the differentially expressed protein candidates detected by iTRAQ, iNOS, was confirmed by western blotting.
Significance:
Our data suggest that iTRAQ technology is an effective tool to study the mechanism by which TMP inhibits activated microglia. TMP decreased the expression of LXR/RXR-mediated iNOS, which reduced microglial activation in response to inflammatory stimuli.
Insights
Tetramethylpyrazine (TMP) reduces neuroinflammation by inhibiting microglial activation. This study reveals TMP decreases inducible nitric oxide synthase (iNOS) expression, offering a novel therapeutic mechanism for neurodegenerative diseases.
Area of Science:
- Neuroscience
- Immunology
- Biochemistry
Background:
- Neurodegenerative diseases pose a significant global health burden.
- Tetramethylpyrazine (TMP) shows therapeutic potential for neurodegenerative diseases by inhibiting microglial activation.
- The precise molecular mechanisms of TMP's action remain unclear.
Purpose of the Study:
- To elucidate the molecular mechanisms by which tetramethylpyrazine (TMP) inhibits microglial activation.
- To identify key proteins and pathways affected by TMP in activated microglia.
Main Methods:
- Proteomic analysis using iTRAQ labeling coupled with LC TRIPLE-TOF to identify proteins affected by TMP in lipopolysaccharide-activated microglia.
- Western blotting to validate candidate proteins, specifically inducible nitric oxide synthase (iNOS).
Main Results:
- Proteomic analysis identified 5187 unique proteins, with 266 differentially expressed in response to TMP.
- Differentially expressed proteins, including iNOS and ERO1-like protein (ERO1L), suggest roles in reducing cellular oxidation.
- Pathway analysis indicated involvement in liver X receptor/retinoid X receptor (LXR/RXR) activation and nitric oxide/reactive oxygen species production.
- iNOS was confirmed as a differentially expressed protein by western blotting.
Conclusions:
- iTRAQ technology is effective for studying TMP's mechanism in inhibiting microglial activation.
- TMP reduces microglial activation by decreasing LXR/RXR-mediated iNOS expression.
- This provides a molecular basis for TMP's therapeutic effects in neuroinflammation.
