Medicine and Health Sciences Commons^™

The P38alpha Mitogen-Activated Protein Kinase Limits The Cns Proinflammatory Cytokine Response To Systemic Lipopolysaccharide, Potentially Through An Il-10 Dependent Mechanism, Adam D. Bachstetter, Bin Xing, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The p38α mitogen-activated protein kinase (MAPK) is a well-characterized intracellular kinase involved in the overproduction of proinflammatory cytokines from glia. As such, p38α appears to be a promising therapeutic target for neurodegenerative diseases associated with neuroinflammation. However, the in vivo role of p38α in cytokine production in the CNS is poorly defined, and prior work suggests that p38α may be affecting a yet to be identified negative feedback mechanism that limits the acute, injury-induced proinflammatory cytokine surge in the CNS.

METHODS: To attempt to define this negative feedback mechanism, we used two in vitro and two in vivo models …

Transition From An M1 To A Mixed Neuroinflammatory Phenotype Increases Amyloid Deposition In App/Ps1 Transgenic Mice, Erica M. Weekman, Tiffany L. Sudduth, Erin L. Abner, Gabriel J. Popa, Michael D. Mendenhall, Holly M. Brothers, Kaitlyn Braun, Abigail Greenstein, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The polarization to different neuroinflammatory phenotypes has been described in early Alzheimer's disease, yet the impact of these phenotypes on amyloid-beta (Aβ) pathology remains unknown. Short-term studies show that induction of an M1 neuroinflammatory phenotype reduces Aβ, but long-term studies have not been performed that track the neuroinflammatory phenotype.

METHODS: Wild-type and APP/PS1 transgenic mice aged 3 to 4 months received a bilateral intracranial injection of adeno-associated viral (AAV) vectors expressing IFNγ or green fluorescent protein in the frontal cortex and hippocampus. Mice were sacrificed 4 or 6 months post-injection. ELISA measurements were used for IFNγ protein levels and …

Il-4 Signaling Drives A Unique Arginase+/Il-1Β+ Microglia Phenotype And Recruits Macrophages To The Inflammatory Cns: Consequences Of Age-Related Deficits In Il-4rα After Traumatic Spinal Cord Injury, Ashley M. Fenn, Jodie C.E. Hall, John C. Gensel, Phillip G. Popovich, Jonathan P. Godbout

Spinal Cord and Brain Injury Research Center Faculty Publications

Alternative activation of microglia/macrophages (M2a) by interleukin (IL)-4 is purported to support intrinsic growth and repair processes after CNS injury. Nonetheless, alternative activation of microglia is poorly understood in vivo, particularly in the context of inflammation, injury, and aging. Here, we show that aged mice (18-19 months) had reduced functional recovery after spinal cord injury (SCI) associated with impaired induction of IL-4 receptor α (IL-4Rα) on microglia. The failure to successfully promote an IL-4/IL-4Rα response in aged mice resulted in attenuated arginase (M2a associated), IL-1β, and chemokine ligand 2 (CCL2) expression, and diminished recruitment of IL-4Rα⁺ macrophages to …

Expression Of Mir-15/107 Family Micrornas In Human Tissues And Cultured Rat Brain Cells, Wang-Xia Wang, Robert J. Danaher, Craig S. Miller, Joseph R. Berger, Vega G. Nubia, Bernard R. Wilfred, Janna H. Neltner, Christopher M. Norris, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

The miR-15/107 family comprises a group of 10 paralogous microRNAs (miRNAs), sharing a 5' AGCAGC sequence. These miRNAs have overlapping targets. In order to characterize the expression of miR-15/107 family miRNAs, we employed customized TaqMan Low-Density micro-fluid PCR-array to investigate the expression of miR-15/107 family members, and other selected miRNAs, in 11 human tissues obtained at autopsy including the cerebral cortex, frontal cortex, primary visual cortex, thalamus, heart, lung, liver, kidney, spleen, stomach and skeletal muscle. miR-103, miR-195 and miR-497 were expressed at similar levels across various tissues, whereas miR-107 is enriched in brain samples. We also examined the expression …