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- Creators: College of Integrative Sciences and Arts
- Creators: Caplan, Michael
Description
Background: Both puberty and diets composed of high levels of saturated fats have been shown to result in central adiposity, fasting hyperinsulinemia, insulin resistance and impaired glucose tolerance. While a significantly insulinogenic phenotypic change occurs in these two incidences, glucose homeostasis does not appear to be affected. Methods: Male, Sprague-dawley rats were fed diets consisting of CHOW or low fat (LF), High Fat Diet and High Fat Diet (HFD) with supplementary Canola Oil (Monounsaturated fat). These rats were given these diets at 4-5 weeks old and given intraperitoneal and oral glucose tolerance tests(IPGTT; OGTT) at 4 and 8 weeks to further understand glucose and insulin behavior under different treatments. (IPGTT: LF-n=14, HFD-n=16, HFD+CAN-n=12; OGTT: LF-n=8, HFD-n=8, HFD+CAN-n=6). Results: When comparing LF fed rats at 8 weeks with 4 week glucose challenge test, area under the curve (AUC) of glucose was 1.2 that of 4 weeks. At 8 weeks, HFD fed rats AUCg was much greater than LF fed rats under both IPGTT and OGTT. When supplemented with Canola oil, HFD fed rats AUC returned to LF data range. Despite the alleviating glucose homeostasis affects of Canola oil the AUC of insulin curve, which was elevated by HFD, remained high. Conclusion: HFD in maturing rats elevates fasting insulin levels, increases insulin resistance and lowers glucose homeostasis. When given a monounsaturated fatty acid (MUFA) supplement fasting hyperinsulinemia, and late hyperinsulinemia still occur though glucose homeostasis is regained. For OGTT HFD also induced late hyper c-peptide levels and compared to LF and HFD+CAN, a higher c-peptide level over time.
ContributorsRay, Tyler John (Author) / Caplan, Michael (Thesis director) / Herman, Richard (Committee member) / Towner, Kali (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / W. P. Carey School of Business (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
White-nose syndrome (WNS) is a fungal infection devastating bat populations throughout eastern North America. WNS is caused by a fungus, Pseudogymnoascus destructans (Pd), that invades the skin of hibernating bats. While there are a number of treatments being researched, there is currently no effective treatment for WNS that is deployed in the field, except a few being tested on a limited scale. Bats have lowered immune function and response during hibernation, which may increase susceptibility to infection during the winter months. Antimicrobial peptides (AMPs) are a crucial component of the innate immune system and serve as barriers against infection. AMPs are constitutively expressed on skin and facilitate wound healing, stimulate other immune responses, and may also stay active on bat skin during hibernation. AMPs are expressed by all tissues, have direct killing abilities against microbes, and are a potential treatment for bats infected with Pd. In this investigation, the fungicidal activity of several readily available commercial AMPs were compared, and killing assay protocols previously investigated by Frasier and Lake were replicated to establish a control trial for use in future killing assays. Another aim of this investigation was to synthesize a bat-derived AMP for use in the killing assay. Sequences of bat-derived AMPs have been identified in bat skin samples obtained from a large geographic sampling of susceptible and resistant species. Contact was made with GenScript Inc., the company from which commercially available AMPs were purchased, to determine the characteristics of peptide sequences needed to synthesize an AMP for lab use. Based on recommendations from GenScript Inc., peptide sequences need to have a hydrophobicity of less than 50% and a sequence length of less than 50 amino acids. These criteria serve as a potential barrier because none of the known bat-derived sequences analyzed satisfy both of these requirements. The final aim of this study was to generate a conceptual model of the immune response molecules activated when bats are exposed to a fungal pathogen such as Pd. Overall, this work investigated sources of variability between trials of the killing assay, analyzed known bat-derived peptide sequences, and generated a conceptual model that will serve as a guideline for identification of immune response molecules on the skin of bats in future proteomics work.
ContributorsBarton, Madisen L (Author) / Moore, Marianne (Thesis director) / Penton, Christopher (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
White-nose syndrome (WNS) is a fungal disease that infects hibernating bats of multiple species across large portions of eastern North America. To date, WNS has been responsible for the deaths of over seven million bats. It is not yet known why certain species are able to resist infection. Since the fungus invades the skin and some resistant species show no signs of the characteristic cutaneous lesions, it seems likely that resistant species contain specific defense mechanisms within their skin, such as antimicrobial peptides (AMPs) and other immunologically relevant proteins expressed by specific cell types or as secreted soluble components. Proteomics could be a useful tool for understanding differences in susceptibility, and could help identify AMPs that could be synthesized and used as control agents against the spread of the causative fungus. This study is the first to optimize proteomics methods for bat wing tissues in order to compare the skin proteomes of species variably impacted by WNS, including those of two endangered species. Further tests are planned to investigate methods of increasing protein yield without altering the size of the tissue sample collected, as well as the analysis of mass spectrometry data from processed skin tissues of five bat species differentially affected by WNS.
ContributorsPatrose, Reena Paulene (Author) / Moore, Marianne (Thesis director) / Steele, Kelly (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Type II diabetes is a serious, chronic metabolic disease that has serious impacts on both the health and quality of life in patients diagnosed with the disease. Type II diabetes is also a very prevalent disease both in the United States and around the world. There is still a lot that is unknown about Type II diabetes, and this study will aim to answer some of these questions. The question posed in this study is whether insulin resistance changes as a function of time after the start of a high fat diet. We hypothesized that peripheral insulin resistance would be observed in animals placed on a high fat diet; and peripheral insulin resistance would have a positive correlation with time. In order to test the hypotheses, four Sprague-Dawley male rats were placed on a high fat diet for 8 weeks, during which time they were subjected to three intraperitonal insulin tolerance tests ((NovoLogTM 1 U/kg). These three tests were conducted at baseline (week 1), week 4, and week 8 of the high fat diet. The test consisted of serially determining plasma glucose levels via a pin prick methodology, and exposing a droplet of blood to the test strip of a glucometer (ACCUCHEKTM, Roche Diagnostics). Two plasma glucose baselines were taken, and then every 15 minutes following insulin injection for one hour. Glucose disposal rates were then calculated by simply dividing the glucose levels at each time point by the baseline value, and multiplying by 100. Area under the curve data was calculated via definite integral. The area under the curve data was then subjected to a single analysis of variance (ANOVA), with a statistical significance threshold of p<0.05. The results of the study did not indicate the development of peripheral insulin resistance in the animals placed on a high fat diet. Insulin-mediated glucose disposal was about 50% at 30 minutes in all four animals, during all three testing periods. Furthermore, the ANOVA resulted in p=0.92, meaning that the data was not statistically significant. In conclusion, peripheral insulin resistance was not observed in the animals, meaning no determination could be made on the relation between time and insulin resistance.
ContributorsBrown, Kellen Andrew (Author) / Caplan, Michael (Thesis director) / Herman, Richard (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
It is presently believed that brown adipose tissue (BAT) is an important tissue in the control of obesity because it has the propensity to increase energy expenditure. The purpose of this study was to attempt to quantify the thermogenesis of BAT when four rats were exposed to a progression of low-fat to high-fat diet. Exogenous norepinephrine (NE) injections (dose of 0.25 mg/kg i.p.) were administered in order to elicit a temperature response, where increases in temperature indicate increased activity. Temperatures were measured via temperature sensing transponders that had been inserted at the following three sites: interscapular BAT (iBAT), the abdomen (core), and lower back (reference). Data showed increased BAT activity during acute (2-3 weeks) high fat diet (HFD) in comparison to low fat diet (LFD), but a moderate to marked decrease in BAT activity during chronic HFD (6-8 weeks) when compared to acute HFD. This suggests that while a HFD may initially stimulate BAT in the short-term, a long-term HFD diet may have negative effects on BAT activation.
ContributorsSivak, Hanna (Author) / Sweazea, Karen (Thesis director) / Herman, Richard (Committee member) / Caplan, Michael (Committee member) / School of Life Sciences (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Across large areas of eastern and midwestern North America, a severe reduction in multiple populations of bat species has been observed as the result of the emerging fungal disease, white-nose syndrome (WNS). WNS is caused by a psychrophilic (i.e. cold loving) fungus, Pseudogymnoascus destructans (Pd), that invades the skin of bats during hibernation. Recent studies have shown that during hibernation, bats have decreased immune system activity which would suggest increased susceptibility to infection. Antimicrobial peptides (AMPs) are an important component of the innate immune system and are expressed constitutively within all tissues that serve as barriers against infection. Killing pathogens at the level of the skin could prevent the need for more complex immune responses likely inhibited during hibernation, and therefore AMPs could be critical in combating infection by Pd and reducing population loss of susceptible bat species. In this investigation, the fungicidal activity of commercially available AMPs derived from the skin of multiple taxa, including amphibians, catfish, and humans were compared in order to study immunity at the level of the skin. Additionally, our aim was to create optimal methods for a low-cost antimicrobial-assay protocol that would provide quantitative results. We found that killing abilities at various concentrations of dermaseptin S-1 against Ca ATCC 10231 were consistent with literature values, while our values for magainin 2 and parasin 1 were far from the values previously recorded by other studies. It is possible that some differences can be accounted for by the difference in antimicrobial assay procedures, but our findings suggest potential differences to the well-known killing abilities of certain peptides nonetheless. Overall, the protocol established for the antimicrobial assays using serial dilutions and Sabouraud Dextrose plates was successful.
ContributorsFrazier, Eric (Co-author) / Lake, Alexis M. (Co-author) / Moore, Marianne (Thesis director) / Penton, Christopher (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Across large areas of eastern and midwestern North America, a severe reduction in multiple populations of bat species has been observed as the result of the emerging fungal disease, white-nose syndrome (WNS). WNS is caused by a psychrophilic (i.e. cold loving) fungus, Pseudogymnoascus destructans (Pd), that invades the skin of bats during hibernation. Recent studies have shown that during hibernation, bats have decreased immune system activity which would suggest increased susceptibility to infection. Antimicrobial peptides (AMPs) are an important component of the innate immune system and are expressed constitutively within all tissues that serve as barriers against infection. Killing pathogens at the level of the skin could prevent the need for more complex immune responses likely inhibited during hibernation, and therefore AMPs could be critical in combating infection by Pd and reducing population loss of susceptible bat species. In this investigation, the fungicidal activity of commercially available AMPs derived from the skin of multiple taxa, including amphibians, catfish, and humans were compared in order to study immunity at the level of the skin. Additionally, our aim was to create optimal methods for a low-cost antimicrobial-assay protocol that would provide quantitative results. We found that killing abilities at various concentrations of dermaseptin S-1 against Ca ATCC 10231 were consistent with literature values, while our values for magainin 2 and parasin 1 were far from the values previously recorded by other studies. It is possible that some differences can be accounted for by the difference in antimicrobial assay procedures, but our findings suggest potential differences to the well-known killing abilities of certain peptides nonetheless. Overall, the protocol established for the antimicrobial assays using serial dilutions and Sabouraud Dextrose plates was successful.
ContributorsLake, Alexis (Co-author) / Frazier, Eric (Co-author) / Moore, Marianne (Thesis director) / Penton, Christopher (Committee member) / W.P. Carey School of Business (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
White-nose syndrome (WNS) is a cutaneous fungal infection caused by Pseudogymnoascus destructans (Pd) which was first observed in the United States in 2006. Pd infects bats during hibernation and leads to the development of cutaneous lesions and behavioral changes that can result in the animal's death. This study generated the first complete bat skin proteome for the WNS resistant gray bat (Myotis grisescens) to optimize sample preparation methods and identify immune proteins that may signal resistance. Wing tissue was collected from a female gray bat and processed in a Barocycler using 4M or 8M urea followed by an in-gel trypsin digestion of pooled samples and processing of separate samples without digestion specifically to capture and identify small antimicrobial peptides. Both undigested and digested samples were analyzed using a Thermo Fisher LTQ Orbitrap Velos mass spectrometer and interpreted using PEAKS software. A total of 29 immune proteins were identified including the antimicrobial peptide dermcidin. This method will be applied to a larger range of samples from five species variably impacted by WNS to compare skin proteomes with the aim of identifying immune proteins that are responsible for resistance at the barrier where Pd invades.
ContributorsBoone, Brianna Marie (Author) / Moore, Marianne (Thesis director) / Steele, Kelly (Committee member) / College of Integrative Sciences and Arts (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Adaptive thermogenesis is an innate mechanism that assists the body in controlling its core temperature that can be stimulated in two ways: cold and diet. When adaptive thermogenesis is stimulated through diet, the metabolic rate of the body should increase and the metabolic efficiency of the body should decrease. This activation should, theoretically, help to control weight gain. A protocol was developed to study four male Sprague-Dawley rats throughout a fourteen week period through the measurement of brown adipose tissue blood flow and brown adipose tissue, back, and abdomen temperatures to determine if diet induced thermogenesis existed and could be activated through norepinephrine. The sedative used to obtain blood flow measurements, ketamine, was discovered to induce a thermal response prior to the norepinephrine injection by mimicking the norepinephrine response in the sympathetic nervous system. This discovery altered the original protocol to exclude an injection of norepinephrine, as this injection would have no further thermal effect. It was found that ketamine sedation excited diet induced thermogenesis in periods of youth, low fat diet, and early high fat diet. The thermogenic capacity was found to be at a peak of 2.1 degrees Celsius during this time period. The data also suggested that the activation of diet induced thermogenesis decreased as the period of high fat diet increased, and by week 4 of the high fat diet, almost all evidence of diet induced thermogenesis was suppressed. This indicated that diet induced thermogenesis is time and diet dependent. Further investigation will need to be made to determine if prolonged high fat diet or age suppress diet induced thermogenesis.
ContributorsJayo, Heather Lynn (Author) / Caplan, Michael (Thesis director) / Herman, Richard (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Corynorhinus townsendii, a bat species residing in north-central Arizona, has historically been observed hibernating in highly ventilated areas within caves and abandoned mines, but there is little to no specific data regarding this tendency. Understanding how air movement may influence hibernacula selection is critical in bettering conservation efforts for Arizona bats, especially with white-nose syndrome continuing to devastate bat species populations throughout the United States. My study aimed to begin filling in this knowledge gap. I measured wind speed in three known Arizona hibernacula during the winter hibernation season and combined this data with the locations of bats observed throughout each of the three survey locations. I modeled our findings using a generalized linear model, which confirmed that wind speed is indeed a predictor of C. townsendii roost selection.
ContributorsKitchel, Heidi (Author) / Moore, Marianne (Thesis director) / Saul, Steven (Committee member) / Barrett, The Honors College (Contributor) / College of Integrative Sciences and Arts (Contributor)
Created2022-05