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Description
There is preclinical evidence that the detrimental cognitive effects of hormone loss can be ameliorated by estrogen therapy (Bimonte, Acosta, & Talboom, 2010), however, one of the primary concerns with current hormone therapies is that they are nonselective, leading to increased risk of breast and endometrial cancers as well as

There is preclinical evidence that the detrimental cognitive effects of hormone loss can be ameliorated by estrogen therapy (Bimonte, Acosta, & Talboom, 2010), however, one of the primary concerns with current hormone therapies is that they are nonselective, leading to increased risk of breast and endometrial cancers as well as heart disease. Thus, in order to achieve a successful and clinically relevant long-term hormone therapy option, it is optimal to find an estrogen therapy regimen that is selective to its target tissue. Recently, phytoestrogens have been found to exert selective, beneficial effects on cognition and brain. For example, genistein and diadzein produce neuroprotective effects in cognitive brain regions (Zhao, Chen, & Diaz Brinton, 2002). The purpose of this study was threefold: 1) to examine the cognitive impact of phytoestrogens in young ovariectomized rats, 2) to replicate the dose effects found in the Luine study (Luine et al., 2006), while controlling for manufacturer differences, and 3) to assess if the rodent diet used in our laboratory has an estrogenic-like cognitive impact.The current findings suggest that, at least for object memory, diets containing varying amounts of phytoestrogens can alter cognition, with diets containing high amounts of phytoestrogens showing potential benefits to this type of memory.
ContributorsWhitton, Elizabeth Nicole (Author) / Bimonte-Nelson, Heather (Thesis director) / Presson, Clark (Committee member) / Baxter, Leslie (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2013-05
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Description
Chronic stress often leads to cognitive deficits, especially within the spatial memory domain mediated by the hippocampus. When chronic stress ends and a no-stress period ensues (i.e., washout, WO), spatial ability improves, which can be better than non-stressed controls (CON). The WO period is often the same duration as the

Chronic stress often leads to cognitive deficits, especially within the spatial memory domain mediated by the hippocampus. When chronic stress ends and a no-stress period ensues (i.e., washout, WO), spatial ability improves, which can be better than non-stressed controls (CON). The WO period is often the same duration as the chronic stress paradigm. Given the potential benefit of a post-stress WO period on cognition, it is important to investigate whether this potential benefit of a post-stress WO period has long-lasting effects. In this project, chronic restraint (6hr/d/21d) in Sprague-Dawley rats was used, as it is the minimum duration necessary to observe spatial memory deficits. Two durations of post-stress WO were used following the end of chronic restraint, 3 weeks (STR-WO3) and 6 weeks (STR-WO6). Immediately after chronic stress (STR-IMM) or the WO periods, rats were tested on various cognitive tests. We corroborated past studies that chronic stress impaired spatial memory (STR-IMM vs CON). Interestingly, STR-WO3 and STR-WO6 failed to demonstrate improved spatial memory on a radial arm water maze task, performing similarly as STR-IMM. Performance outcomes were unlikely from differences in anxiety or motivation because rats from all conditions performed similarly on an open field task and on a simple object recognition paradigm, respectively. However, performance on object placement was unusual in that very few rats explored, suggesting some degree of anxiety or fear in all groups. One possible interpretation of the unusual results of the 3 week washout group may be attributed to the different spatial memory tasks used across studies or external factors from the study. Further exploration of these other factors led to the conclusion that they did not play a role and the STR-WO3 RAWM data were anomalous to other studies. This suggests that a washout period following chronic stress may not be fully understood.
ContributorsFlegenheimer, Aaron Embden (Author) / Conrad, Cheryl (Thesis director) / Bimonte-Nelson, Heather (Committee member) / Ortiz, J. Bryce (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Description
Drospirenone (DRSP) is a novel, pharmacologically unique synthetic progestin with properties more similar to the endogenous progestogen, progesterone, than any other progestin currently on the market. While a significant amount of research has been conducted on the risks associated with DRSP, the impact of DRSP on cognition, especially in reference

Drospirenone (DRSP) is a novel, pharmacologically unique synthetic progestin with properties more similar to the endogenous progestogen, progesterone, than any other progestin currently on the market. While a significant amount of research has been conducted on the risks associated with DRSP, the impact of DRSP on cognition, especially in reference to learning and memory, is not well understood. However, it is imperative to fully understand the cognitive effects of DRSP, both alone and in combination with EE (as taken in a combined oral contraceptive [COC]), so that women and their physicians can make a fully-informed decision when deciding to take a DRSP-containing COC. Study 1 examined the effects of three doses of DRSP in order to determine the optimal dose for combining with EE, and found that the medium dose of DRSP (30 µg/day) enhanced spatial working memory performance. In Study 2, the medium dose of DRSP from Study 1 was combined with low (0.125 µg/day) and high (0.3 µg/day) doses of EE to examine the effects of DRSP as taken with EE in a COC. The results from Study 2 indicated that when DRSP was combined with a low, but not high, dose of EE, spatial working memory impairments were seen at the highest working memory load. Anxiety-like behavior was evaluated using the OFT, and DRSP was shown to decrease measures of anxiety-like behavior. Additionally, while treatment with a high dose of EE decreased several measures of anxiety-like behavior, a low dose of EE did not, suggestive of a dose response. Taken together, the findings presented from both studies suggest that some of the cognitive effects of the combination of DRSP with EE are different than those of either hormone administered on its own. Further exploration in a preclinical, ovary-intact animal model is a next step to fully understand these effects in the translational context of a contraceptive, given that women taking an EE-DRSP combination are typically ovary-intact.
ContributorsPoisson, Mallori Louise (Author) / Bimonte-Nelson, Heather (Thesis director) / Doane, Leah (Committee member) / School of Nutrition and Health Promotion (Contributor) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Description
The aim of this study was to determine whether IUD administration, with and without the presence of Levo, and with and without the presence of the ovaries, impacts cognition in a rat model. Rats received either Sham or Ovariectomy (Ovx) surgery (removal of the ovaries), plus either no IUD, a

The aim of this study was to determine whether IUD administration, with and without the presence of Levo, and with and without the presence of the ovaries, impacts cognition in a rat model. Rats received either Sham or Ovariectomy (Ovx) surgery (removal of the ovaries), plus either no IUD, a Blank IUD (without Levo), or a Levo-releasing IUD (Levo IUD), enabling us to evaluate the effects of Ovx and the effects of IUD administration on cognition. Two weeks after surgery, all treatment groups were tested on the water radial arm maze, Morris water maze, and visible platform task to evaluate cognition. At sacrifice, upon investigation of the uteri, it was determined that some of the IUDs were no longer present in animals from these groups: Sham\u2014Blank IUD, Ovx\u2014Blank IUD, and Sham\u2014Levo IUD. Results from the remaining three groups showed that compared to Sham animals with no IUDs, Ovx animals with no IUDs had marginally impaired working memory performance, and that Ovx animals with Levo IUDs as compared to Ovx animals with no IUDs had marginally enhanced memory performance, not specific to a particular memory type. Results also showed that Ovx animals with Levo IUDs had qualitatively more cells in their vaginal smears and increased uterine horn weight compared to Ovx animals with no IUDs, suggesting local stimulation of the Levo IUDs to the uterine horns. Overall, these results provide alternative evidence to the hypothesis that the Levo IUD administers Levo in solely a localized manner, and suggests that the possibility for the Levo IUD to affect reproductive cyclicity in ovary-intact animals is not rejected. The potential for the Levo IUD to exert effects on cognition suggests that either the hormone does in fact systemically circulate, or that the Levo IUD administration affects cognition by altering an as yet undetermined hormonal or other feedback between the uterus and the brain.
ContributorsStrouse, Isabel Martha (Author) / Bimonte-Nelson, Heather (Thesis director) / Glenberg, Arthur (Committee member) / Sirianni, Rachael (Committee member) / Conrad, Cheryl (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
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Description

Existing knowledge of Latina sexual health disparities has been discussed through traditional barriers such as financial, language, or location. Contraceptive use is proven to greater economic, social, and health outcomes across women of all racial and ethnic backgrounds. This study aims to explore another factor, specifically among young Mexican-American women

Existing knowledge of Latina sexual health disparities has been discussed through traditional barriers such as financial, language, or location. Contraceptive use is proven to greater economic, social, and health outcomes across women of all racial and ethnic backgrounds. This study aims to explore another factor, specifically among young Mexican-American women – whether or not cultural perceptions on sexual health impact the decision to use contraception. In- depth qualitative interviews were conducted among first-generation Mexican-American women ages 18-25 residing in Arizona. The results show that while negative cultural perceptions faced additional barriers in seeking contraception, it was not a complete deterrent for any participant. If anything, this motivated participants to actively destigmatize sexual health in their communities by speaking more openly about their experiences with others.

ContributorsNaranjo, Carla Andrea (Author) / Gonzales, Angela (Thesis director) / Coronado, Irasema (Committee member) / School of Politics and Global Studies (Contributor) / School of International Letters and Cultures (Contributor) / School of Social Transformation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The cerebellum is recognized for its role in motor movement, balance, and more recently, social behavior. Cerebellar injury at birth and during critical periods reduces social preference in animal models and increases the risk of autism in humans. Social behavior is commonly assessed with the three-chamber test, where a mouse

The cerebellum is recognized for its role in motor movement, balance, and more recently, social behavior. Cerebellar injury at birth and during critical periods reduces social preference in animal models and increases the risk of autism in humans. Social behavior is commonly assessed with the three-chamber test, where a mouse travels between chambers that contain a conspecific and an object confined under a wire cup. However, this test is unable to quantify interactive behaviors between pairs of mice, which could not be tracked until the recent development of machine learning programs that track animal behavior. In this study, both the three-chamber test and a novel freely-moving social interaction test assessed social behavior in untreated male and female mice, as well as in male mice injected with hM3Dq (excitatory) DREADDs. In the three-chamber test, significant differences were found in the time spent (female: p < 0.05, male: p < 0.001) and distance traveled (female: p < 0.05, male: p < 0.001) in the chamber with the familiar conspecific, compared to the chamber with the object, for untreated male, untreated female, and mice with activated hM3Dq DREADDs. A social memory test was added, where the object was replaced with a novel mouse. Untreated male mice spent significantly more time (p < 0.05) and traveled a greater distance (p < 0.05) in the chamber with the novel mouse, while male mice with activated hM3Dq DREADDs spent more time (p<0.05) in the chamber with the familiar conspecific. Data from the freely-moving social interaction test was used to calculate freely-moving interactive behaviors between pairs of mice and interactions with an object. No sex differences were found, but mice with excited hM3Dq DREADDs engaged in significantly more anogenital sniffing (p < 0.05) and side-side contact (p < 0.05) behaviors. All these results indicate how machine learning allows for nuanced insights into how both sex and chemogenetic excitation impact social behavior in freely-moving mice.
ContributorsNelson, Megan (Author) / Verpeut, Jessica (Thesis director) / Bimonte-Nelson, Heather (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2024-05