The purpose of the study was to determine if perceived severity of the consequences of physical inactivity is an important component for exercise motivation in college students. The participants of the study were 581 college students who had enrolled in HSC 160, Fundamentals of Human Health, at Ball State University during the spring semester of 2001. Using a cross-sectional data collection process, participants completed a survey instrument consisting of the stages of change for exercise scale, the perceived severity of the consequences of physical inactivity scale, and demographic questions.The data were analyzed using both univariate and bivariate analyses. Specific descriptive and inferential statistic analyses were used to: 1) determine the degree of association between the participants' perceived severity and their identified stages of change for exercise, 2) examine the relationship between the stages of change for exercise and the participants' demographic characteristics, and 3) determine the difference between perceived severity of consequences of physical inactivity and the Participants' demographic characteristics.The results indicated that those who perceived the threat of a health condition as a result of not being physically active to be high were more likely to exercise regularly. Males and females differed in their exercise stage of change with males being more likely in the maintenance stage whereas females were more likely to be in the preparation stage. Also, perceived severity of the consequences from the lack of physical activity was greater in females than males, suggesting that those men who exercise regularly do so, but not exclusively for preventing negative health conditions.The results of this study should be useful to health and physical education instructors to assist them with organizing and tailoring appropriate physical activity lecture topics and emphasizing the severity of the consequences to those who are not physically active.Finally, additional research should be conducted in order to determine what factors affect perceived severity of a health threat as it relates to physical inactivity such as demographics, sociopsychological, and structural variables, to help identify all the possible factors that could impact future program planning efforts. / Department of Biology

The aim of this research was to implement and evaluate guidelines that will be used by treatment support counsellors in an attempt to increase client adherence to antiretroviral treatment.

HIV-associated lipodystrophy (HIVLD) syndrome is a condition comprising abnormalities in distribution of body fat and metabolism of lipids and glucose that arises in HIV-infected patients on long-term antiretroviral therapy. This thesis describes clinical research into aspects of the natural history and treatment of HIVLD, as well as molecular research into its pathogenesis centred on subcutaneous adipose tissue. Results demonstrate HIVLD to be a treatment-induced syndrome characterised by initial gains in body fat followed by selective, progressive loss of limb fat. Exposure to thymidineanalogue nucleoside reverse transcriptase inhibitors (tNRTI) induces lipoatrophy through mitochondrial dysfunction of which inhibition of mitochondrial RNA expression, rather than mitochondrial DNA depletion, is an early feature. Mitochondrial dysfunction is associated with decreases in expression of peroxisome proliferatoractivated receptor gamma (PPAR??), an adipocyte transcription factor, which helps explain how tNRTI exposure leads to the loss of adipocyte function. Once established, lipoatrophy is characterised by mitochondrial DNA depletion, although this depletion occurs throughout the mitochondrial genome, suggesting an underlying cause other than inhibition of DNA polymerase gamma. HIVLD is a difficult syndrome to treat. Lipoatrophy is resistant to treatment with rosiglitazone, an agonist of PPAR??, which is ineffective in the setting of ongoing tNRTI therapy and mitochondrial dysfunction. Dyslipidaemia is also difficult to treat as use of pravastatin in the setting of ongoing exposure to protease inhibitors results in only modest declines in fasting cholesterol concentrations. Gains in central fat, such as that seen in patients with buffalo hump, are associated with insulin resistance and diabetes, but only occur in a relatively small percentage of treated patients, suggesting a role for genetic factors in its development. Use of strategies such as avoidance of tNRTI in firstline ART, genetic screening to identify those at risk of toxicities and targeted selection of interventions in subgroups of affected patients, may help prevent this syndrome occurring and better treat those patients in which it has already occurred.

M.Sc. / To successfully intervene in the HIV/AIDS pandemic, knowledge of the pathogenesis of the disease and factors that stimulate or inhibit viral replication are crucial. Plants are expected to produce antiviral compounds since viruses form one of the major groups of plant pathogens. The objective in this project was to investigate the effects of 6 plant extracts on immune responses as well as evaluate their potential anti-HIV activity. Plant species tested were: Hypoxis hemerocal/idea, Elephantorrhiza elephantina, Spirulina platensis, Echinacea purpurea, Echinacea pal/ida and Cannabis sativa. Extracts were prepared via 24 hour extraction or 12 hour reflux in H20, methanol and ethanol in a 1:5 ratio. The crude extracts were analysed by TLC and HPLC and shown to consist of complex related mixtures of compounds. Using LC-MS, partial identification of methanol extracts revealed the following expected compounds: 9- octadecenoic acid (E)- in Hypoxis hemerocallidea, 4H-1-benzopyran-4-one,2-(3,4- dihydroxyphenyl)-7 -(13-D-glucopyranosyloxy)-5-hydroxy- in E/ephantorrhiza e/ephantina, ethanol,2-butoxy-,phosphate in Spirulina platensis, 2-propenoic acid,3-(3,4-dihydroxyphenyl)- in Echinacea purpurea, 2-propenoic acid,3-(3,4-dihydroxyphenyl)- in Echinacea pal/ida and ~-9- tetrahydrocannabivarin in Cannabis sativa tincture. Viability assays using tetrazolium salts (XTT) gave a qualitative picture of events allowing us to assess host cell responses and extract toxicity. Extracts exhibited intrinsic absorbances at some visible wavelengths but did not interfere at the wavelengths used in this viability assay. Having analysed cell viability it was thought prudent to report on the type of cell death induced by either HIV or the extracts, so Annexin-V (indicator of apoptosis) and PI (indicator of necrosis) detected by flow cytometry was employed. Results obtained revealed that cells were driven towards necrosis rather than apoptosis. None of the extracts showed significant in vitro toxicity in CEMss, CEMNKR. U937, Jurkat and PM1 cells or ex vivo in PBMC at a concentration range of 1000f..lg/ml-4f.!g/ml. Viability assays were also an indirect indication of HIV's effect on the cells. As for the effect of extracts on the immune system, IL-2 secretion was stimulated by most of the extracts. The effect of plant extracts on HIV activity was also investigated by looking at core protein levels (p24 was generally decreased by methanol extracts), reverse transcriptase activity (no detectable influence) and envelope glycoprotein levels (gp120 levels were only marginally reduced). It appears that Echinacea purpurea, Echinacea pal/ida and Spirulina platensis have immune enhancing abilities, while Hypoxis hemerocallidea, Elephantorrhiza e/ephantina and Cannabis sativa have dual purposes by enhancing both immunity and inhibiting HIV activity.

The acquired immunodeficiency syndrome (AIDS) in humans, which is caused by the human immunodeficiency virus type 1 (HIV-1) remains among the leading causes of death worldwide. Although HAART has reduced HIV mortality significantly, adhering to the recommended drug schemes, significant toxicities experienced by treated patients, and the high mutation rate of the virus that seem to easily circumvent the action of these drugs emphasize the need for alternative treatment strategies. Medicinal plants are a good source for the discovery of novel antimicrobial chemotherapeutic agents. Reverse transcription is the most essential step for viral replication to succeed successfully. This makes reverse transcriptase the prime target for antiviral therapy against HIV. Emphasis was placed on the discovery of plants with inhibitory activity against HIV-1 reverse transcriptase. Crude extracts from the active plant(s) was screened in vitro for their ability to suppress HIV replication in suitable cell systems. The potential of isolating and identifying the active principle(s) was also investigated. Crude extracts from different parts of Gunnera perpensa showed similar amounts of inhibition: aqueous extracts (97% „b 0.110%SD), methanol/chloroform extracts (94% „b 2.374%SD), rhizome extracts (96% „b 0.475%SD), stem extracts (94% „b 3.723%SD), leaf extracts (96% „b 1.097% SD). Crude extracts were found to be significantly (P„T0.027) non-toxic to CEM.NKR.CCR5 cells and PBMCs at 5 ƒÝg/ml. In acutely infected CEM.NKR.CCR5 cells, acutely infected PBMCs, and chronically infected PBMCs Gunnera perpensa extracts did not significantly (P>0.05) increase cell viability or reduced HIV core protein content, over 4 days. The in vitro test did therefore not reflect the findings with the reverse transcriptase assay. Activity-guided fractionations of Gunnera perpensa rhizome extract lead to the collection of a significantly active fraction. NMR studies revealed the presence of an epimeric mixture of glucose ¡§contaminants¡¨ in this active fraction. The presence of these ¡§contaminants¡¨ concealed the true structure of the active principle. Gunnera perpensa was identified as containing a potential active principle that significantly inhibits recombinant HIV reverse transcriptase. Unfortunately, in vitro experiments could not confirm this finding. The identity and structure of the active principle remains unidentified. Future studies will be concerned with in vitro antiviral studies of the pure active principle. Furthermore, preliminary tests indicated that some of the original collection of crude extracts had anti-bacterial and anti-malarial activities. These findings can be investigated in future. / Dr. D. Meyer

Alzheimer's disease is a progressive neurodegenerative disorder, in which there is a marked decline in neurotransmitters, especially those of the cholinergic pathways. One of the approaches to the symptomatic treatment of Alzheimer's disease is the inhibition of the breakdown of the neurotransmitter acetylcholine, using an acetylcholinesterase inhibitor. One such drug tested, is the organophosphate, metrifonate. Any drug used for the treatment of neurodegenerative disorders should preferably not induce further neurological damage. Thus, in the present study, we investigated whether or not metrifonate is neuroprotective. The in vivo and in vitro effect of this drug on free radicals generation shows that metrifonate increases the level ofthese reactive species. Lipid peroxidation induced using quinolinic acid (QA) and iron (II) and show that metrifonate increased the peroxidative damage induced by using quinolinic acid. Metrifonate is also able to induce lipid peroxidation both in vivo and in vitro. This was reduced in vitro in the presence of melatonin. Using iron (II), in vi/ro, there was no significant difference in the level of lipid peroxidation in the presence of this drug. An investigation of the activity of the mitochondrial electron transport chain and complex I of the electron transport chain in the presence of metrifonate revealed that metrifonate reduces the activity of the electron transport chain at the level of complex I. The activity of the mitochondrial electron transport chain was restored in the presence of melatonin. Pineal organ culture showed that metrifonate does not increase melatonin production. Histological and apoptosis studies show that tissue necrosis and apoptosis respectively, occur in the presence of this agent, which is reduced in the presence of melatonin. Metal binding studies were performed USing ultraviolet spectroscopy, and electrochemical analysis to examine the interaction of metrifonate with iron (II) and iron (III). No shift in the peak was observed in the ultraviolet spectrum when iron (ll) was added to metrifonate. Electrochemical studies show that there may be a very weak or no ligand formed between the metal and drug. This study shows that while drugs such as metrifonate may be beneficial in restoring cognitive function in Alzheimer's disease, it could also have the potential to enhance neurodegeneration, thus worsening the condition, in the long term. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

The potent analgesic property of acetylsalicylic acid and acetaminophen makes these the most commonly used analgesics in the world. Easy accessibility and cost effectiveness of these agents are attractive to patients seeking pain relief. However, the abuse of nonnarcotic analgesics such as acetaminophen and acetylsalicylic acid by alcoholics and patients seeking to relieve dysphoric moods is well documented. These agents therefore impact on the brain neurotransmitter levels and therefore all processes involved in the synthesis and metabolism of neurotransmitters may be affected. The use of non-narcotic analgesics has been reported to reduce the incidence of neurodegenerative disorders such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The mode of action by which acetylsalicylic acid and acetaminophen elicit neuroprotection is however unclear as many mechanisms of action have been inconclusively postulated. The first part of this study aims to elucidate the various mechanisms by which acetylsalicylic acid and acetaminophen affect the enzymes responsible for the catabolism of tryptophan, which is a precursor for the mood elevating neurotransmitter serotonin, as well as to investigate whether these agents alter the interplay between serotonin and pineal indole metabolism. The second part of this study focuses on the neuroprotective properties of acetylsalicylic acid and acetaminophen utilizing the neurotoxic metabolite of the kynurenine pathway, quinolinic acid and the potent Parkinsonian neurotoxin, 1-methyl-4-phenylpyridinium (MPP+). The ability of acetylsalicylic acid and acetaminophen to alter TRP metabolism was determined by investigating the effects of these agents on the primary enzymes of the kynurenine pathway i.e. tryptophan 2, 3-dioxygenase and indoleamine 2,3-dioxygenase as well as to investigate whether these agents would have any effects on 3-hydroxyanthranilic acid oxygenase. 3-Hydroxyanthranilic acid oxygenase is the enzyme responsible for the synthesis of quinolinic acid. Acetylsalicylic acid and acetaminophen alter tryptophan metabolism by inhibiting tryptophan 2, 3-dioxygenase and indoleamine 2,3-dioxygenase thus increasing the availability of tryptophan for the production of serotonin. Acetylsalicylic acid and acetaminophen also inhibit 3-hydroxyanthranilic acid oxygenase thus implying that these agents could reduce quinolinic acid production. Acetaminophen administration in rats induces a rise in serotonin and norepinephrine in the forebrain. Acetylsalicylic acid curtails the acetaminophen-induced rise in brain norepinephrine levels as well as enhances serotonin metabolism, indicating that analgesic preparations containing both agents would be advantageous, as this would prevent acetaminophen-induced mood elevation. The results from the pineal indole metabolism study show that acetylsalicylic acid enhances pineal metabolism of serotonin whereas acetaminophen induces an increase in melatonin levels in the pineal gland. Neuronal damage due to oxidative stress has been implicated in several neurodegenerative disorders such as AD and PD. The second part of the study aims to elucidate and characterize the mechanism by which acetylsalicylic acid and acetaminophen afford neuroprotection. The hippocampus is an important region of the brain responsible for memory. Agents such as quinolinic acid that are known to induce stress in this area have detrimental effects and could lead to various types of dementia. The striatum is also a vulnerable region to oxidative stress and hence (MPP+), which is toxic for this particular region of the brain, was also used as a neurotoxin. The results show that ASA and acetaminophen alone and in combination, are potent superoxide anion scavengers. In addition, the results imply that these agents offer protection against oxidative stress and lipid peroxidation induced by several neurotoxins in rat brain particularly, the hippocampus and striatum. Histological studies, using Nissl staining and Acid fuchsin, show that acetylsalicylic acid and acetaminophen are able to protect hippocampal neurons against quinolinic acidinduced necrotic cell death. Immunohistochemical investigations show that QA induces apoptotic cell death in the hippocampus, which is inhibited by ASA and acetaminophen. In addition, ASA and acetaminophen inhibited MPP+ induced apoptotic cell death in the rat striatum. The study also sought to elucidate possible mechanisms by which ASA and acetaminophen exert neuroprotective effects in the presence of MPP+ as these agents are shown to prevent the MPP+-induced reduction in dopamine levels. The results show that acetylsalicylic acid and acetaminophen inhibit the action of this neurotoxin on the mitochondrial electron transport chain, a common source of free radicals in the cell. In addition, these agents were shown to block the neurotoxic effects of MPP+ on the enzymatic defence system of the brain i.e. superoxide dismutase, glutathione peroxidase and catalase. The reduction in glutathione levels induced by MPP+ is significantly inhibited by acetylsalicylic acid and acetaminophen. The results imply that these agents are capable of not only scavenging free radicals but also enhance the cell defence mechanism against toxicity in the presence of MPP+. These agents also block the MPP+-induced inhibition of dopamine uptake into the cell. This would therefore reduce auto-oxidation of dopamine thus implying another mechanism by which these agents exert a neuroprotective role in MPP+-induced neurotoxicity. The discovery of neuroprotective properties of acetylsalicylic acid and acetaminophen is important considering the high usage of these agents and the increased incidence in neurological disorders. The findings of this thesis point to the need for clinical studies to be conducted as the results show acetylsalicylic acid and acetaminophen to have a definite role to play as antioxidants. This study therefore provides novel information regarding the neuroprotective effects of these agents and favours the use of these agents in the treatment of neurodegenerative disorders, such as AD and PD, in which oxidative stress is implicated.

The purpose of this research study was to evaluate the effectiveness of the Arthritis Self-Management Program (ASMP), developed by Dr. K. Lorig, on a population of persons with scleroderma. This particular condition is a type of arthritis (also known as progressive systemic sclerosis) involving a disorder of the small blood vessels and connective tissues. It is characterized by the induration and thickening of the skin and by inflammatory, fibrotic, ischemic, and degenerative changes in the tissues throughout the body. Eighteen people, most of which were female, in the Vancouver Lower Mainland with the diagnosis of scleroderma volunteered for this study. Quantitative and qualitative methodological orientations were used to collect and analyze the data. A quasi-experimental, pretest-posttest nonequivalent comparison group design was used. Self-administered, standardized questionnaires were distributed to a sample of subjects to collect the quantitative data, and a standardized open-ended interview questionnaire was used to collect the qualitative data. The quantitative questionnaire comprised research instruments including The Visual Analogue Pain Scale, Health Assessment Questionnaire, Centre for Epidemiological Studies of Depression Scale, Cantril Quality of Life Scale, Arthritis Self-Efficacy Scale, and Health Locus of Control Scale. The quantitative findings indicated that no statistically significant improvements in health status were found. However, clinically significant improvement trends in health status were found. The qualitative findings generally indicated that the experimental subjects enjoyed the ASMP, found it to increase their perceived level of coping with the management of scleroderma, and found the ASMP to be a positive learning experience. With the exception of the ASMP being limited in its specific application to people with scleroderma, it proved to be a feasible patient education course for these people. / Arts, Faculty of / Social Work, School of / Graduate

Small molecules are powerful tools to probe biological systems and cure diseases. In the scope of this dissertation, small molecules were applied to study three distinct disease models: cancer, Sedaghatian-type spondylometaphyseal dysplasia (SSMD), and COVID-19. First, encouraged by the recently reported vulnerability of drug-resistant, metastatic cancers to GPX4 (Glutathione Peroxidase 4) inhibition, we examined the basis for nanomolar potency of proof-of-concept GPX4 inhibitors, which revealed an unexpected allosteric binding site. Through hierarchical screening of a lead-optimized compound library, we identified novel small molecules binding to this allosteric site. Second, a homozygous point mutation in the GPX4 gene was identified in three living patients with SSMD. With a structure-based analysis and cell models of the patient-derived variant, we found that the missense variant significantly changed the protein structure and caused substantial loss of enzymatic function. Proposed proof-of-concept treatments were subsequentially validated in patient fibroblasts. Our further structural investigation into the origin of the reduced enzymatic activity revealed a key residue modulating GPX4 enzymatic function. We also found that the variant alters the degradation of GPX4, unveiling the native degradation mechanism of GPX4 protein. Third, driven by the recent urgent need for COVID-19 antiviral therapeutics, we utilized the conservation of 3CL protease substrate-binding pockets across coronaviruses to identify four structurally divergent lead compounds that inhibit SARS-CoV-2 3CL protease. With structure-based optimization, we ultimately identified drug-like compounds with < 10 nM potency for inhibiting the SARS-CoV-2 3CL protease and blocking SARS-CoV-2 replication in human cells.

Parkinson’s disease (PD) is a multi-organ disorder. It is diagnosed from motor impairments that arise from neurodegeneration in the midbrain. However, the disease begins decades earlier in the gut prior to involvement of the brain. PD is characterized by persistent inflammation, both in the brain and in the periphery in addition to neurodegeneration. Here, I investigate the role of the adaptive immune system in disease pathogenesis and as a driver of prodromal symptoms of PD in both humans and mice. In Chapter 1, I introduce Parkinson’s disease, its pathological hallmarks and the progression of the symptoms, and discuss genetic and environmental influences. Then, I elaborate on the inflammatory phenotypes observed in the disease and recent work describing the role of inflammation in animal models for PD. In Chapter 2, I examine the autoimmune features of Parkinson’s disease from analysis of patients’ blood. I found that approximately 40% of PD patients possess aspects of autoimmunity against α-synuclein. By screening peripheral blood mononuclear cells of patients and healthy controls for potential neoantigens derived from α-synuclein protein, I identified two antigenic regions of the protein that elicit an immune response. The immune responses to a specific α-synuclein neo-antigens were linked to unique HLAs that are over-represented in our PD cohort and are associated with PD in genome wide association studies (GWAS). In Chapters 3 and 4, I describe the effects of recapitulating α-synuclein autoimmunity in a humanized mouse strain expressing the HLA allele risk for PD. In Chapter 3, I show that the humoral and cellular immunity is mounted against α-synuclein in the humanized mice, similar to what is observed in PD patients; however, there is no inflammation or immune response toward the brain. In Chapter 4, I show how the autoimmune response to α-synuclein induces inflammation and neurodegeneration in the gut leading to constipation in mice, recapitulating the prodromal aspects of the human disease. Finally, in Chapter 5, I discuss the implications of these findings for α-synuclein autoimmunity in the periphery, gut and brain in Parkinson’s disease. I also elaborate on the implications of these findings for potential future diagnostic screening and treatments for Parkinson’s disease.