Theses and Dissertations
This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students.
Displaying 1 - 4 of 4
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- All Subjects: Tyramine
- All Subjects: Vegetarians
Description
Western diets, high in dietary fat and red meat, are associated with hyperglycemia and weight gain, symptoms that promote insulin resistance and diabetes. Previous studies have shown that elevated glucose promotes glycation of circulating proteins such as albumin, which is thought to lead to hyperglycemia complications. It was hypothesized that diets with no meat consumption (pesco-vegetarian and lacto-vegetarian) would reduce protein glycation, in comparison to a diet with meat. Forty six healthy adult omnivorous subjects were randomized into one of three groups and instructed to either consume red meat (i.e. meat) or poultry twice per day (control), eliminate meat and increase fish consumption (pesco-vegetarian), or adopt a vegetarian diet devoid of fish, meat or poultry (lacto-vegetarian) for four weeks. Fasting plasma samples were collected from participants at baseline and after 4 weeks of the dietary intervention. Plasma glucose concentrations were measured using a commercially available kit. Percent glycated albumin was measured on a separate aliquot of plasma by mass spectrometry. Plasma glucose concentrations were significantly increased following 4-weeks of pesco-vegetarian diet (P=0.002, paired t-test). Neither the lacto-vegetarian (P=0.898) or the control diet (P=0.233) affected plasma glucose concentrations. Despite the significant increase in plasma glucose following a pesco-vegetarian diet, no change in percent glycated albumin was observed (P>0.50, ANOVA). These findings may indicate a protective effect of the pesco-vegetarian diet on protein glycation in the presence of elevated plasma glucose and suggest the need for additional studies to examine the link between increased fish consumption and glucose regulation.
ContributorsRaad, Noor (Author) / Sweazea, Karen (Thesis director, Committee member) / Borges, Chad (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Male reproductive dysfunction accounts for almost half of male infertility cases, yet the signaling mechanisms involved in the male reproductive system remain unclear. Although the exact cause of male reproductive dysfunction varies, obtaining a better understanding of the modulators of smooth muscle contractions may provide new targets for the treatment of male reproductive conditions. The male reproductive tract, consisting of the testes, epididymis, vas deferens, and penis, is lined with innervated smooth muscle fibers that transport spermatozoa through the system. Contractions of these smooth muscle fibers can be modulated by neurotransmitters and hormones, like dopamine and norepinephrine, as well as biogenic amines. The focus of this study is on the biogenic amine tyramine, which is produced by the breakdown of tyrosine via decarboxylation. Tyramine has been shown to modulate vasoconstriction and increase blood pressure due to its effect on smooth muscle contractions. This study has found that tyramine localizes in male reproductive tissues and modulates smooth muscle contractions. Age and environment were also found to play a significant role in the expression of tyramine and its associated receptor, TAAR1.
ContributorsSteadman, Solange (Author) / Baluch, Debra (Thesis advisor) / Roberson, Robert (Committee member) / Sweazea, Karen (Committee member) / Arizona State University (Publisher)
Created2023
Description
Human preterm labor is the single most significant issue in modern obstetrics andgynecology, affecting ten percent of pregnancies, constituting the leading cause of infant death, and contributing significantly to chronic childhood disease. Obstetricians and reproductive scientists are faced with the major challenge of trying to increase the understanding of the complex molecular and cellular signals that regulate uterine activity during human pregnancy and labor. Even though preterm labor accounts for a large portion of perinatal mortality and morbidity, there still is not an effective therapeutic strategy for the treatment or prevention of preterm labor. This dissertation presents tyramine as an alternative modulator of uterine activity. In this dissertation the aims were as follows: 1) to investigate the localization of tyramine and trace amine associated receptor 1 (TAAR1) in the mouse uterine horn using immunohistochemistry as well as confirm the presence of tyramine in the uterine tissue using high performance liquid chromatography, 2) identify which TAAR 1-9 subtypes were present in the mouse uterine horn using RT-qPCR, 3) investigate ultrastructural differences in the mouse uterine horn following tyramine and dopamine treatment using transmission electron microscopy and 4) investigate pinopod ultrastructure as well as pinopod ultrastructural differences following tyramine and dopamine treatment. The research presented in this dissertation showed: 1) tyramine has very specific localization in the mouse endometrium, mainly in the uterine glands, TAAR1 is localized all throughout the perimetrium, myometrium and endometrium, and that tyramine was confirmed and quantified using HPLC, 2) TAAR 1- 9 genes are expressed in trace levels in the mouse uterine horn, 3) tyramine influences changes in endometrial ultrastructure, and 4) tyramine influences changes in pinopod ultrastructure. Ultimately these findings can help with identifying novel treatment options not only for spontaneous preterm labor contractions but also for other uterine related disorders.
ContributorsObayomi, SM Bukola (Author) / Baluch, Debra P (Thesis advisor) / Roberson, Robert (Thesis advisor) / Sweazea, Karen (Committee member) / Brent, Colin (Committee member) / Arizona State University (Publisher)
Created2023
Description
According to a 2016 census, eight million adults conform to a vegetarian diet within the United States, and about 50% of these adults follow a vegan diet. The census determined that plant-based diets are quickly growing in popularity particularly in young adults between the ages of 18 to 34 years. Many Americans are aware of the health benefits of a plant-based diet, however, the dietary risks associated with these diets are not well emphasized. Health concerns such as vitamin deficiencies and altered metabolism are heightened in vegetarian populations.
One Particular nutrient that is commonly lacking in the vegetarian diet is vitamin B12. Vitamin B12 is found mainly in animal-derived food sources such as meat, poultry, fish, dairy, and eggs. Although some vegetarians, called lacto-ovo vegetarians, consume dairy and eggs, vegans do not consume any animal products at all. Vitamin B12 deficiency can have devastating consequences on the human body due to its role as a methylation cofactor. Metabolism, DNA replication, and cancer formation all involve methylation processes.
This cross-sectional, differential study aimed to further understand the relationship between vegetarianism, vitamin B12 status, and methylation capacity in healthy adults. A group of 34 healthy adults (18 vegetarians and 16 omnivores) was recruited to analyze serum B12, homocysteine, methylmalonic acid, serum total folate, and transcobalamin II status. It was hypothesized that (1) vegetarians would have a lower vitamin B12 status, and thus, a lower methylation capacity than omnivores and that (2) low vitamin B12 status would be correlated with low methylation capacity.
The data show that vegetarians did not have significantly lower vitamin B12 methylation capacity status than omnivores. Nor was vitamin B12 status correlated with methylation capacity. However, the data revealed that diet quality had a positive influence on folate status. There was also a statistical trend (p=0.08) for homocysteine reduction in participants consuming high-quality diets. The data herein suggest that methylation capacity may be impacted by the quality of diet rather than the type of diet.
One Particular nutrient that is commonly lacking in the vegetarian diet is vitamin B12. Vitamin B12 is found mainly in animal-derived food sources such as meat, poultry, fish, dairy, and eggs. Although some vegetarians, called lacto-ovo vegetarians, consume dairy and eggs, vegans do not consume any animal products at all. Vitamin B12 deficiency can have devastating consequences on the human body due to its role as a methylation cofactor. Metabolism, DNA replication, and cancer formation all involve methylation processes.
This cross-sectional, differential study aimed to further understand the relationship between vegetarianism, vitamin B12 status, and methylation capacity in healthy adults. A group of 34 healthy adults (18 vegetarians and 16 omnivores) was recruited to analyze serum B12, homocysteine, methylmalonic acid, serum total folate, and transcobalamin II status. It was hypothesized that (1) vegetarians would have a lower vitamin B12 status, and thus, a lower methylation capacity than omnivores and that (2) low vitamin B12 status would be correlated with low methylation capacity.
The data show that vegetarians did not have significantly lower vitamin B12 methylation capacity status than omnivores. Nor was vitamin B12 status correlated with methylation capacity. However, the data revealed that diet quality had a positive influence on folate status. There was also a statistical trend (p=0.08) for homocysteine reduction in participants consuming high-quality diets. The data herein suggest that methylation capacity may be impacted by the quality of diet rather than the type of diet.
ContributorsUgarte, Noel (Author) / Johnston, Carol S (Thesis advisor) / Whisner, Corrie (Committee member) / Sweazea, Karen (Committee member) / Arizona State University (Publisher)
Created2019