Research 151

Decatur, GA, United States

Research 151

Decatur, GA, United States
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Duffy C.M.,Research 151 | Duffy C.M.,University of Minnesota | Xu H.,University of Minnesota | Nixon J.P.,Research 151 | And 4 more authors.
Molecular and Cellular Neuroscience | Year: 2017

Hypothalamic inflammation contributes to metabolic dysregulation and the onset of obesity. Dietary saturated fats activate microglia via a nuclear factor-kappa B (NFκB) mediated pathway to release pro-inflammatory cytokines resulting in dysfunction or death of surrounding neurons. Fatty acid binding proteins (FABPs) are lipid chaperones regulating metabolic and inflammatory pathways in response to fatty acids. Loss of FABP4 in peripheral macrophages via either molecular or pharmacologic mechanisms results in reduced obesity-induced inflammation via a UCP2-redox based mechanism. Despite the widespread appreciation for the role of FABP4 in mediating peripheral inflammation, the expression of FABP4 and a potential FABP4-UCP2 axis regulating microglial inflammatory capacity is largely uncharacterized. To that end, we hypothesized that microglial cells express FABP4 and that inhibition would upregulate UCP2 and attenuate palmitic acid (PA)-induced pro-inflammatory response. Gene expression confirmed expression of FABP4 in brain tissue lysate from C57Bl/6J mice and BV2 microglia. Treatment of microglial cells with an FABP inhibitor (HTS01037) increased expression of Ucp2 and arginase in the presence or absence of PA. Moreover, cells exposed to HTS01037 exhibited attenuated expression of inducible nitric oxide synthase (iNOS) compared to PA alone indicating reduced NFκB signaling. Hypothalamic tissue from mice lacking FABP4 exhibit increased UCP2 expression and reduced iNOS, tumor necrosis factor-alpha (TNF-α), and ionized calcium-binding adapter molecule 1 (Iba1; microglial activation marker) expression compared to wild type mice. Further, this effect is negated in microglia lacking UCP2, indicating the FABP4-UCP2 axis is pivotal in obesity induced neuroinflammation. To our knowledge, this is the first report demonstrating a FABP4-UCP2 axis with the potential to modulate the microglial inflammatory response. © 2017

Stemper B.D.,Medical College of Wisconsin | Stemper B.D.,Research 151 | Hallman J.J.,Medical College of Wisconsin | Peterson B.M.,Medical College of Wisconsin
Journal of Manipulative and Physiological Therapeutics | Year: 2011

Purpose: Chiropractic manipulation of the thoracic spine may induce chest deformations in the anterior-posterior direction. Yet, few studies have examined the biomechanical response of the chest associated with these manipulations. Consequently, an experimental analysis was undertaken to quantify chest compressions resulting from chiropractic thoracic spine manipulations and to estimate amount of risk for injury. Methods: A 2-part study approach was used with a Hybrid III anthropomorphic test dummy. In part 1, the dummy was positioned prone on a chiropractic table and subjected to thoracic spine manipulation by 2 experienced doctors of chiropractic. Chest compressions were quantified in the anterior-posterior direction. Manipulation forces were self-selected, with "typical" and "maximum" efforts examined. In part 2, the dummy was positioned beneath a force-instrumented mechanical piston device. Using the piston, chest compressions were induced with magnitudes identical to those recorded during chiropractic manipulation as well as magnitudes sufficient to induce injury. In all trials, force measurements were recorded. Results: Thoracic manipulations incorporating the typical and maximum efforts by the chiropractors resulted in maximum chest compressions attaining 1.8% and 4.5% of total chest depth, respectively. According to previously developed correlations between chest compression and injury severity defined using the Abbreviated Injury Scale (AIS), maximum chest compression measured during this study was only 22.7% of the compression required for greater than 10% risk of an AIS 1 injury. Abbreviated Injury Scale 1 level injuries are graded as minor severity and correspond to sternum contusion or fracture of a single rib. Conclusions: Results from this preliminary study showed that maximum chest compression during thoracic spine manipulation corresponded to minimal risk of AIS 1 level injuries. © 2011 National University of Health Sciences.

Zone J.J.,University of Utah | Schmidt L.A.,University of Utah | Schmidt L.A.,Veterans Affairs Medical Center | Taylor T.B.,University of Utah | And 9 more authors.
Journal of Immunology | Year: 2011

Dermatitis herpetiformis (DH) is characterized by deposition of IgA in the papillary dermis. However, indirect immunofluorescence is routinely negative, raising the question of the mechanism of formation of these immune deposits. Sardy et al. (2002. J. Exp. Med. 195: 747-757) reported that transglutaminase-3 (TG3) colocalizes with the IgA. We sought to create such deposits using passive transfer of Ab to SCID mice bearing human skin grafts. IgG fraction of goat anti-TG3 or control IgG were administered i.p. to 20 mice. Separately, sera from seven DH patients and seven controls were injected intradermally. Biopsies were removed and processed for routine histology as well as direct immunofluorescence. All mice that received goat anti-TG3 produced papillary dermal immune deposits, and these deposits reacted with both rabbit anti-TG3 and DH patient sera. Three DH sera high in IgA anti-TG3 also produced deposits of granular IgA and TG3. We hypothesize that the IgA class anti-TG3 Abs are directly responsible for the immune deposits and that the TG3 is from human epidermis, as this is its only source in our model. These deposits seem to form over weeks in a process similar to an Ouchterlony immunodiffusion precipitate. This process of deposition explains the negative indirect immunofluorescence results with DH serum. Copyright © 2011 by The American Association of Immunologists, Inc.

Zahner D.,Emory University | Zahner D.,Research 151 | Zhou X.,Emory University | Zhou X.,Research 151 | And 8 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2010

Macrolide resistance is a major concern in the treatment of Streptococcus pneumoniae. Inducible macrolide resistance in this pneumococcus is mediated by the efflux pump MefE/Mel. We show here that the human antimicrobial peptide LL-37 induces the mefE promoter and confers resistance to erythromycin and LL-37. Such induction may impact the efficacy of host defenses and of macrolide-based treatment of pneumococcal disease. Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Cho H.,University of Tennessee Health Science Center | Cho H.,Research 151 | Zook J.,University of Memphis | Banner T.,University of Memphis | And 6 more authors.
Tissue Engineering and Regenerative Medicine | Year: 2014

Self-assembled gold monolayers offer several advantages for the realization of novel modified electrodes for biosensor applications. This is due to their ability to decrease non-specific adsorption and provide for covalent attachment of biomolecules. Surfaces for these applications require the precise control of ligand density, the ability to immobilize ligands, and in situ-modulation of ligand activity. In this study, we focused our studies on the immobilization of antibody on a gold monolayer surface. We self-assembled thioctic acid onto the gold surface as an anchor point for the immobilization of anti-fibrinogen onto the surface. The modifications to the gold surface were characterized by ELISA, ellipsometry, and AFM.

Duffy C.M.,Research 151 | Duffy C.M.,University of Minnesota | Nixon J.P.,Research 151 | Nixon J.P.,University of Minnesota | And 2 more authors.
Molecular and Cellular Neuroscience | Year: 2016

Palmitic acid (PA), an abundant dietary saturated fatty acid, contributes to obesity and hypothalamic dysregulation in part through increase in oxidative stress, insulin resistance, and neuroinflammation. Increased production of reactive oxygen species (ROS) as a result of PA exposure contributes to the onset of neuronal apoptosis. Additionally, high fat diets lead to changes in hypothalamic gene expression profiles including suppression of the anti-apoptotic protein B cell lymphoma 2 (Bcl-2) and upregulation of the pro-apoptotic protein B cell lymphoma 2 associated X protein (Bax). Orexin A (OXA), a hypothalamic peptide important in obesity resistance, also contributes to neuroprotection. Prior studies have demonstrated that OXA attenuates oxidative stress induced cell death. We hypothesized that OXA would be neuroprotective against PA induced cell death. To test this, we treated an immortalized hypothalamic cell line (designated mHypoA-1/2) with OXA and PA. We demonstrate that OXA attenuates PA-induced hypothalamic cell death via reduced caspase-3/7 apoptosis, stabilization of Bcl-2 gene expression, and reduced Bax/Bcl-2 gene expression ratio. We also found that OXA inhibits ROS production after PA exposure. Finally, we show that PA exposure in mHypoA-1/2 cells significantly reduces basal respiration, maximum respiration, ATP production, and reserve capacity. However, OXA treatment reverses PA-induced changes in intracellular metabolism, increasing basal respiration, maximum respiration, ATP production, and reserve capacity. Collectively, these results support that OXA protects against PA-induced hypothalamic dysregulation, and may represent one mechanism through which OXA can ameliorate effects of obesogenic diet on brain health. © 2016

Stein J.J.,SUNY Upstate Medical University | Stein J.J.,Research 151 | Iwuchukwu C.,SUNY Upstate Medical University | Iwuchukwu C.,Research 151 | And 4 more authors.
Molecular and Cellular Biochemistry | Year: 2013

Angioplasty causes local vascular injury, leading to the release of thrombospondin-1 (TSP-1), which stimulates vascular smooth muscle cell (VSMC) migration and proliferation, important steps in the development of intimal hyperplasia. Transforming growth factor beta 2 (TGF-β2) and hyaluronic acid synthase (HAS) are two pro-stenotic genes upregulated in VSMCs by TSP-1. We hypothesized that inhibition of TGF-β2 or HAS would inhibit TSP-1-induced VSMC migration, proliferation, and TSP-1 signaling. Our data demonstrate that Inhibition of either TGF-β2 or HAS inhibited TSP-1-induced VSMC migration and proliferation. Activation of ERK 1 was decreased by TGF-β2 inhibition and unaffected by HAS inhibition. TGF-β2 and HAS are not implicated in TSP-1-induced thbs1 expression, while they are each implicated in TSP-1-induced expression of their own gene. In summary, TSP-1-induced VSMC migration and proliferation rely on intact TGF-β2 signaling and HAS function. TSP-1 activation of ERK 1 is dependent on TGF-β2. These data further expand our understanding of the complexity of TSP-1 cellular signaling and the involvement of TGF-β2 and HAS. © 2013 Springer Science+Business Media New York (outside the USA).

Dang I.,Hines Veterans Administration Hospital | Dang I.,Loyola University | De Vries G.H.,Research 151 | De Vries G.H.,Virginia Commonwealth University
Neurochemical Research | Year: 2011

Malignant peripheral nerve sheath (MPNST) cell lines derived from patients with neurofibromatosis type 1 (NF!) were found to have basal cAMP levels which are two-fold higher than cAMP levels in normal human adult Schwann cells (nHSC). PCR analysis also revealed that normal adult human Schwann cells express mRNA for types Ill, IV, and IX adenylyl cyclase (AC) while NF1 MPNST cells express AC mRNA of types II, V, and VIII in addition to expressing all the isoforms of normal adult human Schwann cells. Further PCR analysis revealed that NF1 MPNST lines express mRNA for EP2 and EP4 prostaglandin receptors whereas nHSC only express mRNA for the EP2 receptor. Exogenous prostaglandins alone or in combination with PDGF BB induced greater increases in cAMP levels and proliferation of NF1 MPNST cells compared to nHSC. We conclude that aberrant cAMP signaling in NF1 MPNST cells contributes to tumor formation in NF1 patients. © Springer Science+Business Media, LLC 2011.

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