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Turner et al. LPS preconditioning neuroprotective
to the brain, but acute LPS preconditioning provides American Foundation of Pharmaceutical Education
“inflamaprepping” that primes the nervous system Pre-doctoral Fellowship. Brandon Lucke-Wold also
for response to injury. [43] Although inflamaprepping received a Neurosurgery Research and Education
is not a universal to all TBIs, it offers a potential Foundation Medical Student Summer Research
therapeutic advantage for a certain subset of Fellowship, a Sigma Xi Grants in Aid of Research,
individuals, namely soldiers and athletes. Soldiers American Association of Pharmaceutical Scientists
and athletes are at increased risk of concussion and Pre-doctoral fellowship, and American Medical
subconcussive injury. Prevent injury and enhancing Association Foundation Seed Grant.
recovery in these individuals is receiving increasing
attention. Inflamaprepping with a systemically Conflicts of interest
injected agent such as low-dose LPS is clinically There are no conflicts of interest.
feasible and may limit gliosis and subsequent
glial scar formation by preparing the brain for Patient consent
trauma. Ultimately this would facilitate rapid No patients were involved.
axonal regeneration guided by preserved myelin
tracts. In the current study, we have shown that Ethical approval
inflamaprepping inhibits gliosis, downregulates the Ethical approval was obtained prior to the
OSMR receptor, and shifts the microglia phenotype commencement of the study.
balance away from the pro-inflammatory M1
state, thereby decreasing neurodegeneration and REFERENCES
promoting neuroprotection. The benefits of this
neuroprotection on preventing behavioral decline 1. Walshe CM, Laffey JG, Kevin L, O’Toole D. Sepsis protects
will be investigated in a future study. the myocardium and other organs from subsequent ischaemic/
reperfusion injury via a MAPK-dependent mechanism. Intensive
Care Med Exp 2015;3:35.
There are some limitations to the present study. 2. Longhi L, Gesuete R, Perego C, Ortolano F, Sacchi N, Villa P,
Firstly, we did not assess post-injury behavior. Based Stocchetti N, De Simoni MG. Long-lasting protection in brain
on our histopathologic findings, we expect that trauma by endotoxin preconditioning. J Cereb Blood Flow Metab
LPS preconditioning prevents behavioral deficits 2011;31:1919-29.
following TBI, but needs to be verified in a future 3. Lozano D, Gonzales-Portillo GS, Acosta S, de la Pena I, Tajiri
study. Secondly, we did not or examine glial marker N, Kaneko Y, Borlongan CV. Neuroinflammatory responses
to traumatic brain injury: etiology, clinical consequences, and
expression later than 7 days after LPS treatment. therapeutic opportunities. Neuropsychiatr Dis Treat 2015;11:97-
This data would have indicated the current state of 106.
gliosis and inflammation at the time of injury. 4. Schaafsma W, Zhang X, van Zomeren KC, Jacobs S, Georgieva
PB, Wolf SA, Kettenmann H, Janova H, Saiepour N, Hanisch UK,
In conclusion, we have shown for the first time that Meerlo P, van den Elsen PJ, Brouwer N, Boddeke HW, Eggen
low-dose LPS preconditioning has protective effects BJ. Long-lasting pro-inflammatory suppression of microglia by
in a diffuse axonal injury model. LPS preconditioning LPS-preconditioning is mediated by RelB-dependent epigenetic
silencing. Brain Behav Immun 2015;48:205-21.
prevented both astrocyte and microglia activation 5. Hayakawa K, Okazaki R, Morioka K, Nakamura K, Tanaka S,
through downregulation of the OSMR receptor. Ogata T. Lipopolysaccharide preconditioning facilitates M2
This protective effect was verified by reduced activation of resident microglia after spinal cord injury. J Neurosci
FJB staining, indicating decreased degeneration. Res 2014;92:1647-58.
Preconditioning and inflamaprepping may be viable 6. Kumar A, Alvarez-Croda DM, Stoica BA, Faden AI, Loane
targets for TBI treatment and may prevent long- DJ. Microglial/macrophage polarization dynamics following
term behavioral sequelae in patients. Future work traumatic brain injury. J Neurotrauma 2016;33:1732-50.
will examine the long-term functional changes that 7. Zamanian JL, Xu L, Foo LC, Nouri N, Zhou L, Giffard RG,
Barres BA. Genomic analysis of reactive astrogliosis. J Neurosci
lead to neurodegenerative disease progression 2012;32:6391-410.
and tauopathies. We will elucidate whether LPS 8. Johnson VE, Meaney DF, Cullen DK, Smith DH. Animal models
preconditioning reduces tau hyperphosphorylation of traumatic brain injury. Handb Clin Neurol 2015;127:115-28.
and improves behavior following repetitive 9. Oliva AA Jr, Kang Y, Sanchez-Molano J, Furones C, Atkins
injury. Mediating the gliosis response with LPS CM. STAT3 signaling after traumatic brain injury. J Neurochem
2012;120:710-20.
preconditioning may decrease neurodegeneration 10. Godbout JP, Chen J, Abraham J, Richwine AF, Berg BM, Kelley
and slow the development of tauopathy. KW, Johnson RW. Exaggerated neuroinflammation and sickness
behavior in aged mice following activation of the peripheral
Financial support and sponsorship innate immune system. FASEB J 2005;19:1329-31.
Aric Logsdon and Brandon Lucke-Wold received an 11. Mills JD, Bailes JE, Sedney CL, Hutchins H, Sears B. Omega-3
14 Neuroimmunology and Neuroinflammation ¦ Volume 4 ¦ January 20, 2017