Histone lysine methylation is an important epigenetic mark for regulation of gene expression and chromatin organization. Setdb1 (Set domain, bifurcate 1), one of the histone lysine methyltransferases, specifically methylates histone H3 at lysine 9 (H3K9) and participates in transcriptional repression and heterochromatin formation. The major task of my thesis work was to investigate the epigenetic roles of Setdb1 in regulating brain functions. I started my thesis work by examining Setdb1 expression pattern during mouse brain development. The most robust signal of Setdb1 was detected in the fetal brains at embryonic day 12.5, with a ubiquitous distribution in all the proliferative zones, as well as the cortical plate and other regions comprised of postmitotic neurons. The expression of Setdb1 decreased as the brain developed, and this down-regulation profile was correlated to neuronal maturation as examined in a primary culture model of mouse cortical neurons. I then generated CK-Setdb1 transgenic mice, in which a myc-tagged full length mouse Setdb1 was constantly expressed in postmitotic neurons under the control of the CaMK II alpha promoter (CK). The expression of mycSetdb1 was detected in NeuN positive cells throughout most forebrain regions including cerebral cortex, striatum and hippocampus. A sustained increase of Setdb1 in CK-Setdb1 transgenics was verified at both mRNA and protein levels. Furthermore, an increase of H3K9 trimethylation was detected at major satellite DNA repeats in CK-Setdb1forebrains, which indicated that transgene-expressed mycSetdb1 was functionally active in adult brains. The behavioral phenotype of CK-Setdb1 transgenics was examined by using two separate founder lines. Gross neurological functions including body weight, locomotion activity, motor coordination, and breeding behavior were generally normal in CK-Setdb1 mice. CK-Setdb1 mice were further subjected to behavioral paradigms related to mood and cognitive functions. Intriguingly, as compared to the littermate controls, CK-Setdb1 mice represent a lower level of depression as indicated by decreased total immobility in two different behavioral despair tests. Moreover, CK-Setdb1 mice showed an accelerated extinction in the learned helplessness paradigm after a delayed interval (7 days), indicating a faster recovery from an established status of despair. The potential confounding factors, like memory deficits, were ruled out as CK-Setdb1 mice showed normal or even improved performances in different memory-related paradigms. Anxiety scores and stimulant drug response were normal in CK-Setdb1mice. Taken together, these findings suggested that a specific antidepressant-like phenotype was elicited by the over-expression of Setdb1 in adult mice forebrains. To further study the molecular mechanism underlying Setdb1-associated antidepressant-like behavioral changes, I screened for Setdb1-binding sites in a genome-scale by ChIP-on-chip using a tiling microarray from Affymetrix. Unexpectedly, Setdb1 showed a very restricted binding profile with a high specificity towards ionotropic glutamate receptor genes including the NMDA receptor 2B subunit gene Grin2b, which is a new target for the treatment for major depression. An increase of H3K9 dimethylation at Setdb1-binding site on Grin2b locus was detected in CK-Setdb1 hippocampus, which was correlated to a decrease of Grin2b expression as well as an accelerated desensitization of NMDA receptor. Furthermore, Chromosome Conformation Capture (3C) on Grin2b locus revealed a repressive chromatin loop structure, which tethered the distal Setdb1-binding site (~ 32 Kb downstream of transcriptional start site (TSS)) to a proximal intronic region (~12 Kb downstream of TSS) that is enriched for the binding of KAP1, a well-studied Setdb1-interacting transcriptional corepressor. Taken together, our data indicated that Setdb1 repressed Grin2b expression via H3K9 hypermethylation and higher-order chromatin loop formation, which may contribute to the antidepressant-like phenotype we observed in CK-Setdb1mice. The second part of my thesis work was to investigate the role of Setdb1 in the animal model of a neurodevelopmental disorder - Rett syndrome (RTT). Loss-of-function mutations of the gene encoding methyl-CpG binding protein 2 (MECP2) is the primary cause of RTT. There is an overlap between Setdb1- and Mecp2-associated repressive chromatin machineries, which both include histone deacetylase complex, H3K9 methyltransferase, DNA methyltransferase and heterochromatin protein 1 (HP1). Moreover, in contrast to Setdb1, which is downregulated during the cortical neuronal differentiation, Mecp2 is upregulated and the expression level is positively correlated to neuronal maturation. Therefore, we hypothesized that there is a functional redundancy between Setdb1 and Mecp2, and the up-regulation of Setdb1 in mature neurons will compensate for brain deficiency due to the loss of Mecp2. To test this hypothesis, I crossed CK-Setdb1 transgenic mice with nestincre-Mecp2 conditional knockout mice (Mecp2-/y). The behavior changes of CK-Setdb1/Mecp2-/y mice, including body weight, locomotion, motor coordination, and life span, were then compared to Mecp2-/y mice. No significant improvements in behaviors or survival were observed from CK-Setdb1/Mecp2-/y mice. Because the activation of CK promoter is limited to defined population of postmitotic neurons in forebrain, I tested our hypothesis by generating another strain of Setdb1 overexpression mice – tauSetdb1, in which the expression of mycSetdb1 is under the control of an endogenous pan-neuronal active promoter Tau. However, the introduction of tauSetdb1 also failed to rescue Mecp2 deficiency. The life span of tauSetdb1/ Mecp2-/y was even shorter as compared to Mecp2-/y mice (Kaplan-Meier, p=0.07). In conclusion, up-regulation of Setdb1 in adult brain was not sufficient to rescue Mecp2deficiency in the mouse model of RTT. One of the most challenges to study neuronal dysfunctions in brain diseases is the cellular heterogeneity of central nervous system. Current techniques for chromatin studies, including chromatin immunoprecipitation (ChIP) assays, usually lack of single cell resolution and are unable to examine the neurobiological changes in defined cell populations. In the third part of my thesis work, I developed a modified protocol to isolate neuronal nuclei from brain homogenates via Fluorescence-Activated Cell Sorting (FACS). In general, total nuclei was extracted from frozen brains, neuronal nuclei were then immuno-tagged with NeuN and sorted via FACS. Besides the NeuN labeling-FACS protocol, I also generated CK-H2BeGFP transgenic mice, in which a histone H2B-eGFP (enhanced green fluorescent protein) fusion protein was expressed in the nuclei of postmitotic neurons in mouse forebrain. Nuclei extracted from CKH2BeGFP brain were directly applied for FACS sorting. By using this protocol, we routinely got around 6-8 x106neuronal nuclei from one adult mouse forebrain, which was sufficient for ChIP applications followed by single gene PCR and microarray studies. In conclusion, our protocol permits large-scale studies of chromatin modifications or any other nuclei events in defined cell populations from distinct brain regions. Taken together, my dissertation work will lead to a better understanding of the epigenetic roles of histone H3K9 methyltransferase Setdb1 in brain functions, and may provide new targets for the therapeutic treatment of major depression.

The overarching goal of this dissertation was to elucidate the psychosocial and behavioral determinants of medication nonadherence among African Americans with hypertension. One in three Americans in the United States has hypertension, and the prevalence of hypertension among African Americans is among the highest in the world. In addition to healthy behaviors such as following a low-salt and low-fat diet, getting regular exercise, and reducing stress, patients with hypertension must also adhere to antihypertensive medications. Poor medication adherence may be driven by psychosocial and behavioral factors; however, the impact of these factors on medication adherence is unclear especially within the African American community. To date, a paucity of research has examined the relationship between psychosocial and behavioral factors such as reported racial discrimination, John Henryism (a measure of active coping and an unhealthy response to stress) and home remedies with medication nonadherence. However, each of these factors has individually been linked with poorer health outcomes among African Americans. Using data from the TRUST study (2006-2008) the association between these constructs and medication adherence was assessed within our sample of 788 African Americans and a comparison group of 137 White participants with hypertension. Ordinal logistic regression was used to assess the association between racial discrimination, John Henryism, home remedies, and medication adherence. The findings from this research indicated more reported racial discrimination, higher John Henryism scores, and greater use of home remedies were associated with lower medication adherence. These findings yield new knowledge about medication adherence and provide practical insights about the psychosocial and behavioral determinants of medication adherence.

BACKGROUND: Of the 22 known measures of nicotine dependence (ND), none capture the overall disease severity of physical dependence alone. Instead, they capture constructs related to dependence, such as perceived risk, psychological addiction, smoker motivations, or smoking related behaviors, but none of the measures include only physical withdrawal symptoms to capture physical dependence on nicotine. AIM: To develop a range of nicotine dependence measures that capture physical dependence on nicotine. METHODS: The final measures were developed in a cross-sectional study conducted in three phases: 1) candidate item development through literature review and cognitive interviews, 2) developing and pre-testing the survey, and 3) survey administration and psychometric evaluation to validate three distinct measures. The final survey was conducted at four health clinics and three high schools. Psychometric tests used to select the final measure items included inter-item correlations, sensitivity analyses done by subgroup, item-total correlations, convergent validity tests, and confirmatory factor analysis. The final measures were evaluated using confirmatory factor analysis (CFA), internal reliability, total score distributions, and convergent validity correlations. Relative validity analyses were also conducted using a ratio of F-Statistics to compare the ability of each new measure to differentiate dependent smokers as compared previous measures. RESULTS: The final sample included 275 smokers ranging from 14 to 76 years old (mean=30.9, SD=16.2), who smoked an average of 11.5 cigarettes per day (range=0-50, SD=9.4). The sample was 86.5% white and 57.5% male. The three new measures developed included: 1) the 4-item Withdrawal-Induced Craving Scale (WICS) used to capture severity of craving, the most common physical withdrawal symptom; 2) the 12- item Nicotine Withdrawal Symptom Checklist (NWSC), which measures both overall disease severity and the severity of a comprehensive list of individual physical withdrawal symptoms including withdrawal-induced craving, anger, anxiety, depression, headache, insomnia, loss of focus, restlessness, and stress; and 3) the 6-item brief NWSC (NWSC-b), a short measure which only captures overall disease severity. All of the new measures exhibited a unidimensional factor structure loading highly on a single factor (thought to be physical dependence). They also correlated highly (over 0.6) and significantly (p<0.001) to a battery of convergent validity indices including four widely used nicotine dependence measures: Hooked on Nicotine Checklist (HONC), the Autonomy Over Tobacco Scale (AUTOS), the Fagerström Test for Nicotine Dependence (FTND), and self-rated addiction. CONCLUSION: The WICS, NWSC, and NWSC-b provide three distinct validated tools that can be used by researchers, clinicians, and educators to track the progression of physical dependence on nicotine across a range of smoking behaviors and histories.

Background: Mothers’ diets impact their health and the health of their children, but diet quality is suboptimal among women with young children. Evening snacking among women with young children, especially consumption of high-calorie, high-carbohydrate snacks, may impact overall diet quality and glucose metabolism. Short sleep duration and poor sleep quality may be potential risk factors. We examined whether sleep duration and poor sleep quality were associated with diet quality and evening snacking among women with young children. Methods: Data were from the National Health and Nutrition Examination Survey (NHANES) 2005-2012, nationally representative cross-sectional surveys of noninstitutionalized U.S. population. Eligible participants were non-pregnant women aged 20-44 years within 5 years of childbirth who completed two 24-hour dietary recalls and completed questions on sleep duration and quality. Results: Among US women with young children, sleep duration was not associated with diet quality. However, overall sleep quality was associated with poorer diet quality. Short sleep duration was not associated with the consumption of neither evening snacks, nor energy intake from or nutrient consumption of evening snacks. Conclusion: The findings of this dissertation provide information useful for informing the direction of future research of dietary quality and eating behaviors of U.S. women with young children. Studies are needed to explore whether improvement in sleep quality may improve diet quality among women with young children, which has the potential to improve both maternal and children’s health. Research may be better focused on identifying other psychosocial and behavioral risk factors for unhealthy dietary behaviors among US women with young children.

Chronic obstructive pulmonary disease (COPD) is a major health problem in the United States. Acute exacerbations of COPD are primarily responsible for the physical, psychological and economic burden of this disease. Early identification and treatment of exacerbations is important to improve patient and healthcare outcomes. Little is known about how patients with COPD recognize an impending exacerbation and subsequently decide to seek treatment. The purpose of this qualitative descriptive study was to explore and describe symptom recognition and treatment delay in individuals experiencing an acute exacerbation of chronic obstructive pulmonary disease (COPD). Leventhal’s Common Sense Model of illness representation undergirded this study. Using semi-structured interviews, adults hospitalized with an acute exacerbation of COPD were asked to describe their symptom experience and self care behaviors, including treatment seeking, in the days to weeks prior to hospitalization. Data analysis revealed one main theme: Recognizing, responding and reacting to change, and six subthemes: Something’s coming, Here we go again, Seeking urgent treatment, Riding it out, Not in charge anymore and My last day that richly described the COPD exacerbation experience. The study revealed that patients experience an illness prodrome prior to exacerbation and have a recurrent exacerbation symptom pattern that was self-recognized. Treatment seeking was most influenced by the speed and acuity of exacerbation onset, severity of breathlessness, fears of death, nature of patient-provider relationship and the perception of stigmatization during prior healthcare encounters. These findings are important for the development of interventions to improve patient recognition and management of COPD exacerbations in the future.

Little is known about what variables affect self-management practices of adolescents with T1D. Few studies have examined differences in self-management behaviors by stage of adolescence. Similarly, no studies have examined all of the attributes of self-management, including Collaboration with Parents and Goals. In order to fill the gaps in the literature, a secondary data analysis with a descriptive correlation design was conducted to describe T1D self-management behaviors (Collaboration with Parents, Diabetes Care Activities, Diabetes Problem Solving, Diabetes Communication and Goals) during early, middle and late stages of adolescence. This study also examined whether the roles of covariates (regimen, duration of illness (DOI), gender) in self-management behaviors vary by stage of adolescence. Data from 504 subjects aged 13 – 21 years were analyzed and the age variable was transformed into three adolescent stages early (13-14) (n=163), middle (15-16) (n=159) and late (17-21) (n=182). The findings revealed significant differences between adolescent stages on Collaboration with Parents and the Diabetes Problem Solving subscale. The covariate analysis showed no significant effect modification for the covariates and stage on any of the subscales so the results did not differ from the ANOVA model. Covariate analysis showed significant associations between regimen and Collaboration with Parents, Diabetes Care Activities and Diabetes Problem Solving. DOI showed significant associations only with Diabetes Problem solving and gender had significant associations with Diabetes Care Activities and Diabetes Communication. The mean scores on Collaboration with Parents show an incremental decline in collaboration with parents as adolescents move through stages. The higher mean Diabetes Problem Solving scores found in the late adolescent group compared correlated with a higher degree of problem solving in this group when compared to those in the early or middle adolescent stage group. Regimen had significant associations with three of the five subscales suggesting this is an important variable for future study. DOI did not have a significant impact on self-management whereas gender related differences in the areas of Diabetes Activities and Diabetes communication warrant further investigation.

Purpose: Assess the effectiveness of an online intervention to encourage self-management in adolescents with cerebral palsy (CP). Specific Aims: (a) assess effectiveness of an online intervention to promote readiness for self-management in adolescents with CP, (b) describe health literacy and associations with readiness to assume self-management, and (c) evaluate adolescents’ exposure to the online intervention. Hypotheses: (a) intervention subjects would demonstrate improvement in self-management, and (b) subjects with higher health literacy would demonstrate higher self-management capabilities. Framework: Transtheoretical Model of Health Behavior Change Design: Randomized control trial, performed in a multidisciplinary CP clinic at a university based children’s hospital. Instruments used: (a) Transition Readiness Assessment Questionnaire (TRAQ) and (b) the Health Literacy Skills Instrument-SF (HLSI). Due to low engagement, the study terminated early. Intervention subjects were interviewed to assess their limited engagement. Results: Seventy-five percent of subjects demonstrated inadequate HL. Mean baseline TRAQ score (n=24) was 2.71 (SE = .24). Positive associations were found between TRAQ and age (.47, p = .00) and TRAQ and HL (.48, p = .00). Conclusion: Failure to engage with the intervention appeared to be related to: (a) low HL, (b) low TRAQ scores (indicating subjects in contemplation stage) (c) inconsistency between subjects’ preference for learning and delivery of information, and (d) low motivation for self directed learning. Online interventions should be easy to use and include learning preferences. Lessons learned will inform future development of interventions for this population.

Recent studies have shown elevated neuroinflammation in a large subset of individuals diagnosed with schizophrenia. A pro-inflammatory cytokine, tumor necrosis factor-alpha (TNFα), has been directly linked to this neuroinflammation. This study examined the effects of two TNFα modulators (PD2024 and PD340) produced by our collaborators at P2D Bioscience, Inc., to alleviate auditory sensorimotor gating deficits and reduce microglial cell activation present in the polyinosinic:polycytidylic (Poly I:C) rodent model of schizophrenia. Auditory sensorimotor gating was assessed using prepulse inhibition and microglial activation was examined and quantified using immunohistochemistry and confocal microscopy, respectively. Both PD2024 and PD340 alleviated auditory sensorimotor gating deficits and reduced microglia activation and thereby demonstrated the ability to treat both the behavioral and neuroinflammatory aspects of the disorder. These results are significant and suggest that neural TNFα is a potential pharmacological target for the treatment of schizophrenia.

Parenting children with neurodevelopmental deficits (NDDs) is very stressful, more so than the parenting of typically developing children. There is considerable research on the topic of chronic stress experienced by caregivers; however, less is understood of parental stress experienced when raising children with NDDs. The purpose of this study was to examine how parental traits and habits, in the forms of mindfulness and social support levels, affect this cohort's general stress levels. The study was guided by Self-Determination Theory, which explored how parental acts could be classified along a continuum of being intrinsically or extrinsically derived. A convenience sample of parents (n =71) with a child diagnosed with at least one NDD were recruited from online support groups on Facebook. The participants fully completed the Parental Stress Scale to measure parental stress, the Mindful Attention Awareness Scale to measure trait mindfulness, and the Family Support Scale to quantify social support to the family. Correlation analysis and multilinear regression analysis were used to determine that higher levels of social support and mindfulness in the participants predicted lower levels of perceived parental stress; the model was statistically significant, R²=.284, F(2,68)=13.504.p<.001. As a set, the two predictors accounted for 28.4% of the variation in stress. This study helps to promote positive social change by providing informing data on population-specific research, which can assist in the development of empirically supported treatments that could be used by professionals and paraprofessionals in treatment planning, therapies, and psychoeducational interventions.

Many older youth in foster care lack adequate resources and ongoing support in their social networks as they transition into young adulthood, while other youth in these circumstances experience stable social networks providing comprehensive support. Systematically measuring the supportive personal and service-oriented relationships in youth networks expands the scope of inquiry in this area by identifying patterns of social network structure, member composition, and relational qualities that are associated with more or less support provision through formal and informal relationships. These can also be measured over time to observe changes in network form and content and assess network stability. This exploratory study (1) describes the support networks for a small sample of youth with foster care experience who are enrolled in post-secondary education and training programs, (2) assesses changes in these networks over time, and (3) demonstrates the reliability and validity of this methodology for broader use with populations of transition-age foster youth. Findings show that family (biological and foster) and friends are the most prevalent informal supports, relationship ties to parent figures are strongest and provide the most stable and multi-dimensional support, and ties with formal service providers are not as strong, but provide more informational support. The stability of a network ties over time is associated with the breadth of support provided, and network-based social support is associated with post-secondary enrollment at follow-up. Support network profiles are described and interpreted in terms of bonding and bridging social capital. Discussion includes implications for future support network research and guidelines for pre-transition assessment of youth networks in practice.