Posters (Missouri Regional Life Sciences Summit 2010)
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This collection contains the posters presented at the Missouri Regional Life Sciences Summit 2010. Please enter text in the search box above or click on one of the browse options to explore this collection.
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Item Small Business Support for Youth Physical Activity Opportunities(2010-03) Suminski, Richard R.; Tota, Tonya; Dinius, David; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Background: Increasing the number of youth physical activity opportunities (YPAO) (e.g., programs) may be a promising approach for encouraging physically active lifestyles among youth. To do this effectively, we need information on YPAO support systems (e.g., types [financial, in-kind]). Objective: To construct a comprehensive description of YPAO support systems with a focus on the involvement of small businesses. Methods: The first aim was to obtain detailed information about YPAO available to the public including their characteristics (e.g., amenities), operating costs, and the sources of support for the operating costs. The second aim was to describe characteristics related to supporting YPAO. Data from four minority (>70% minority) and four non-minority (<10% minority), inner-city Kansas City neighborhoods was obtained over an eight-month period using quantitative (e.g., surveys, community tours) and qualitative (e.g., key informants) data collection methods. Results: Of the 55 small businesses surveyed, those whose owner was middle-aged (40-50 y), white, with a sports background, and children between 5 and 16 years old were more likely to support YPAO. Only 33% of the business owners surveyed supported YPAO and less than 1% did this to advertise their business. Although YPAO support levels were low, all owners (supporters and non-supporters of YPAO) believed small businesses should support YPAO and how such support can make a difference in the neighborhood. Three main themes emerged regarding the culture of support. First, business owners were more apt to offer support for YPAO if family and friends were involved. Second, business owners tended to be aware of and offer support for broad initiatives focused on neighborhood improvements but experienced barriers to specifically supporting YPAO. For example, information about YPAO needing support was not readily available and few organizations soliciting support for neighborhood initiatives allowed for specific initiatives (e.g., YPAO) to be selected. Third, prominent stakeholders within a neighborhood heavily influenced the culture of giving which suggests they could be used to champion support for YPAO from small businesses. Several barriers to supporting YPAO by small businesses were identified. Small business owners did not track how their support was used and therefore did not receive feedback on the impact of their support. Credit was seldom given to small businesses for their support negating possible returns on their investments (e.g., positive exposure leading to increased business). Owners had little knowledge of who needed help and why they needed help within the neighborhood where their business was located, thus they did not know who or what cause to support. Some owners were not willing to give support because they did not trust the population of the neighborhood where their business was located and did not believe the support would be used for legitimate purposes. This was particularly true for non-minority business owners with a business in a minority neighborhood. Conclusions: Characteristics of small business owners, cultural trends regarding support, and the existence of modifiable barriers to support were identified that may help in the formulation of partnerships to promote youth physical activity.Item Toxicty of a Serotonin-derived Neuromelanin(2010) Miller, Elizabeth D.; Fibuch, Eugene; Seidler, N. W.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Introduction: POCD (Postoperative Cognitive Dysfunction) is associated with increased mortality and disability and may develop as a consequence of lipid peroxidative byproducts (i.e. acrolein), which accumulate with aging. We previously showed that sevoflurane sequesters acrolein, which promotes the formation of a novel species of neuromelanin (NM) that may play a role in POCD. In this current study, we examined the properties of NM and hypothesized that this novel serotonin-derived melanoid (SDM) product may be neurotoxic. Methods: SDM was produced at the interface of an upper aqueous phase containing serotonin and a lower sevoflurane phase containing acrolein. Uni-lamellar vesicles (ULVs) of dioleoyl-phosphatidylcholine were made using an extrusion technique. The interaction of SDM with ULVs was examined using two lipid membrane probes: diphenyl-hexatriene (DPH) and merocyanine (MC). Vesicle disruption was investigated by monitoring the leakage of dye from calcein-loaded ULVs. Absorbance spectra of SDM were also examined. Statistical analysis involved linear regression and unpaired Student t-tests (p<0.05). Results: We observed that SDM decreased DPH fluorescence anisotropy and increased the temperature-dependent change in anisotropy of DPH. SDM increased the ratio of absorbance (570nm/530nm) of MC-bound ULVs. Using calcein-loaded ULVs, SDM increased detergent-mediated calcein leakage. The intense absorbance band below 250nm of SDM was dramatically altered in the presence of ULVs, yielding three well-resolved peaks from a single broad band. Conclusion: From these data we conclude that SDM has the potential of being neurotoxic. Discussion: This study further characterizes SDM as an important species of NM. SDM disorganized the acyl chains and the phospholipid head groups of ULVs. The electronic structure of SDM was dramatically altered upon interaction with ULVs. We also observed that SDM enhanced detergent-mediated leakage of loaded ULVs, suggesting that SDM may be neurotoxic. We propose that inhalational agents that sequester acrolein [3], may promote the production of certain species of NM that deplete local serotonin and enhance neuronal vulnerability.Item Effects of Isoflurane on Plasma-Membrane Calcium ATPase(2010-03) Monaco, J.; Seidler, N. W.; Fibuch, Eugene; Zaidi, A.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Introduction: Plasma membrane Ca2+-ATPase (PMCA) is a transmembrane enzymatic protein present in human neurons, myocytes, and RBCs which plays a role in controlling cellular Ca2+ levels by regulating intracellular ATP. Inhaled anesthetic agents, such as isoflurane, affect transmembrane Ca2+ levels by inhibiting PMCA activity. However, the effect of isoflurane on the interaction between ATP and PMCA has not been studied. We hypothesized that the inhibitory effects of isoflurane on PMCA involve modulation of the interaction between ATP and PMCA. Methods: RBC membranes (containing PMCA) were isolated from human subjects with a previously validated methodology using a calmodulin affinity chromatographic technique. The membranes were treated with isoflurane using human serum albumin as an intermediary with transfer occurring via a dialysis membrane. The treated membranes were then assayed for PMCA activity using the Malachite Green Colorimetric Assay. Activity of PMCA was determined by measuring the release of inorganic phosphate. Varying concentrations of ATP were used to determine the inhibitory effect on PMCA by isoflurane. Results: Isoflurane inhibited basal and CaM-stimulated PMCA activity (nmol of inorganic phosphate per mg PMCA per minute) by 28.6% (P < 0.04) and 66.9% (saturating concentration of 300nM) (P < 0.02), respectively. Significant inhibition of PMCA activity (77.7%) also occurred at CaM concentration as low as 2nM. Isoflurane also inhibited PMCA activity at ATP concentrations between 10[mu]M and 1000[mu]M. Conclusion: Isoflurane inhibited basal and calmodulin-stimulated PMCA activity. Significant inhibition of PMCA activity occurred at all concentrations of CaM and as low as 2nM. Isoflurane suppressed the Michaelis-Menton kinetics of PMCA activity as a function of ATP at concentrations from 10[mu]M to 1000[mu]M. Discussion: We showed for the first time that isoflurane decreases PMCA activity as a function of ATP concentration. We also illustrated that isoflurane decreases the ability of CaM to stimulate PMCA activity. In addition, we introduced a novel physiologic delivery system for isoflurane using albumin as a surrogate transfer molecule. The concentration of isoflurane used for these experiments was not determined. Due to difficulties in studying neuronal PMCA, the RBC isoform was used as a substitute. Further investigations could include exploring the direct effects of isoflurane on CaM and ATP using neuronal isoforms of PMCA, and ensuring clinically relevent concentrations of isoflurane. These data would suggest that a primary biochemical target for isoflurane neural inhibition is intracellular ATP via a direct effect on PMCA activity.Item Regulation of Phosphorylation of Dopamine D3 Receptors in Mouse Striatal Neurons in vivo(2010-03) Rivera, D.; Mao, Li-Min; Fibuch, Eugene; Wang, John Q.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Introduction: Dopamine D3 receptors (D3Rs) are G-protein-coupled receptors. These D3Rs inhibit adenylyl cyclase and the downstream formation of cAMP. Due to their preferential expression in the mesolimbic areas, especially in the nucleus accumbens (NAc), they are known to play a major role in the mesolimbic function. Recently, we found that D3Rs are phosphorylated at serine 229 (Ser229) by Ca2+/calmodulin-dependent protein kinase II (CaMKII). This phosphorylation is subject to the modulation, and the phosphorylation level controls receptor function. In this study, an effort was made to develop a phospho- and site-specific antibody. Using this antibody, we hypothesized that the modulation of D3R phosphorylation at Ser229 by dopamine D1 receptors would occur in the mouse NAc in vivo. Methods: To detect phosphorylation of D3Rs at Ser229 in striatal neurons in vivo, we developed a phospho- and site-specific antibody. A short peptide containing phospho-Ser229 (KRILTRQNpSQCISI) was synthesized and used as an immunogen for producing a polyclonal antibody from rabbits. Upon demonstration of the selectivity of this antibody, we used it in Western blot to monitor changes in Ser229 phosphorylation in striatal neurons in response to dopamine D1 receptor stimulation by a D1 selective agonist SKF81297. Following IACUC approval, adult male mice (CL57/BL6) were randomly divided into 2 groups (n = 3 per group). The animals received an intraperitoneal injection of saline or SKF81297 (1 mg/kg). Animals were sacrificed by cervical dislocation 15 min after drug injection. The NAc was removed and homogenized. Homogenates were centrifuged (1000 g, 10 min), and the supernatant was used for Western blot. Densities of immunoblots were measured using optical scanning and the data were analyzed using Student's t-test (p < 0.05). Results: A series of control experiments validated the selectivity of the antibody against phosphorylated D3Rs at Ser229 (pD3R-Ser229). Using this antibody, we found that the level of pD3R-Ser229 in the NAc was significantly increased in mice treated with a systemic injection of the D1 receptor agonist SKF81297 (1 mg/kg, 15 min) compared to mice treated with saline. Conclusion: Using a phospho- and site-specific antibody against phospho-D3Rs at Ser229, we found that stimulation of dopamine D1 receptors increases phosphorylation of D3Rs in the mouse NAc in vivo. Discussion: Developing a phospho- and site-specific antibody is necessary for detecting changes in D3R phosphorylation in vivo. Using this newly acquired antibody, we found that Ser229 phosphorylation of D3Rs is subject to the modulation by dopamine D1 receptors. This seems to indicate a previously-unrecognized D1-dependent negative feedback control of D3R function given that Ser229 phosphorylation inhibits D3Rs1. In a subpopulation of striatal neurons that co-express D3Rs and D1 receptors, dopamine is able to concurrently enhance the D1-mediated phosphorylation of D3Rs to induce a heterologous desensitization of D3Rs after their activation. This regulation is deemed important for maintaining normal homeostasis of D3R function and could be altered to contribute to various neurological disorders.Item Amphetamine Alters Group I mGluR Expression in the Rat Striatum and Medial Prefrontal Cortex(2010-03) Shaffer, C. B.; Mao, Li-Min; Fibuch, Eugene; Wang, John Q.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Introduction: Group I metabotropic glutamate receptors (mGluR1/mGluR5 subtypes) and their key scaffolding protein Homer1b/c are densely expressed in the striatum. These receptors are believed to play important roles in the regulation of psychostimulant action. The psychostimulant amphetamine increases extracellular glutamate levels, which in turn activates postsynaptic mGluR1/5 in striatal neurons. It is, however, unclear whether amphetamine has any impact on striatal mGluR1/5 expression. In this study, we hypothesized that alterations in mGluR1/5 and Homer 1b/c expression in the rat striatum and medial prefrontal cortex (mPFC) would occur in response to an acute injection of amphetamine in vivo. Methods: Following IACUC approval, adult male Wistar rats received an intraperitoneal injection of saline (n = 4) or amphetamine (5 mg/kg, n = 5). Motor responses to amphetamine were monitored continuously following drug administration. For detecting gene expression, rats were anesthetized and sacrificed 1 h after saline or amphetamine injection. Brains were removed, and the striatum, including the dorsal (caudate putamen) and ventral (nucleus accumbens) striatum, and mPFC were dissected. Synaptic proteins were extracted for Western blot analysis of changes in mGluR1, mGluR5, and Homer1b/c protein levels with specific antibodies. The density of immunoblots was measured using optical scanning. Data were statistically analyzed using Student's t-test (p<0.05). Results: A single injection of amphetamine induced a typical increase in motor activity, confirming that a behaviorally active dose of the drug was used. At this dose, amphetamine markedly reduced mGluR5 protein levels in the striatum, while increasing mGluR5 protein levels in the mPFC. Unlike mGluR5, mGluR1 protein expression in both the striatum and mPFC was not significantly altered in amphetamine-treated rats relative to saline-treated rats. Homer1b/c protein levels in the two regions also remained stable in response to amphetamine administration. Actin protein levels showed no difference between amphetamine- and saline-treated groups. Conclusion: These data identify mGluR5 as a sensitive target of amphetamine. Acute amphetamine exposure is able to alter striatal mGluR5 expression in a subtype- and region-specific manner. Discussion: Amphetamine increases glutamate release in the striatum1 which can activate mGluRs in striatal neurons to produce drug effects. Group I mGluRs have been demonstrated to undergo rapid desensitization following ligand stimulation of the receptor1. Thus, our finding of a loss of synaptic mGluR5 after amphetamine suggests a previously unrecognized mechanism for such desensitization. Of note, amphetamine has no effect on glutamate release in the mPFC1. Future studies are needed to define the role of amphetamine-stimulated mGluR5 expression in this region.