Methemoglobin Is an Endogenous Toll-Like Receptor 4 Ligand—Relevance to Subarachnoid Hemorrhage
Abstract
:1. Introduction
2. Results and Discussion
2.1. Purification of Bovine metHgb
Steps | Protein (mg) | Yield (%) |
---|---|---|
Starting hemolysate | 2094 | 100 |
Centrifugation | 2017 | 96 |
Q-Sepharose | 1822 | 87 |
Ultrafiltration | 1651 | 79 |
PD-10 | 1374 | 66 |
EndoTrap HD | 1364 | 65 |
2.2. metHgb Induces p65 Nuclear Translocation in Microglia
2.3. metHgb Induces Secretion of TNFα in Microglia and Macrophages
2.4. metHgb-Induced TNFα Secretion Is TLR4-Dependent
2.5. metHgb Is the Main Constituent of Hemolysate Responsible for TLR4 Activation
2.6. metHgb Induces Neuroinflammation
2.7. Discussion
3. Experimental Section
3.1. Purification of Bovine metHgb
3.2. Mass Spectrometry
3.3. Cell Culture
3.4. TNFα ELISA
3.5. siRNA Transfection
3.6. In Vivo metHgb Infusion
3.7. Immunohistochemistry
3.8. Statistical Analysis
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Kwon, M.S.; Woo, S.K.; Kurland, D.B.; Yoon, S.H.; Palmer, A.F.; Banerjee, U.; Iqbal, S.; Ivanova, S.; Gerzanich, V.; Simard, J.M. Methemoglobin Is an Endogenous Toll-Like Receptor 4 Ligand—Relevance to Subarachnoid Hemorrhage. Int. J. Mol. Sci. 2015, 16, 5028-5046. https://doi.org/10.3390/ijms16035028
Kwon MS, Woo SK, Kurland DB, Yoon SH, Palmer AF, Banerjee U, Iqbal S, Ivanova S, Gerzanich V, Simard JM. Methemoglobin Is an Endogenous Toll-Like Receptor 4 Ligand—Relevance to Subarachnoid Hemorrhage. International Journal of Molecular Sciences. 2015; 16(3):5028-5046. https://doi.org/10.3390/ijms16035028
Chicago/Turabian StyleKwon, Min Seong, Seung Kyoon Woo, David B. Kurland, Sung Hwan Yoon, Andre F. Palmer, Uddyalok Banerjee, Sana Iqbal, Svetlana Ivanova, Volodymyr Gerzanich, and J. Marc Simard. 2015. "Methemoglobin Is an Endogenous Toll-Like Receptor 4 Ligand—Relevance to Subarachnoid Hemorrhage" International Journal of Molecular Sciences 16, no. 3: 5028-5046. https://doi.org/10.3390/ijms16035028