Jodi M Cahill

Activation of Transcription Factor Nrf-2 and Its Downstream Targets in Response to Moloney Murine Leukemia Virus ts1-Induced Thiol Depletion and Oxidative Stress in Astrocytes

ABSTRACT The neuroimmunodegenerative syndrome that develops in mice infected with ts1, a mutant of Moloney murine leukemia virus, resembles human AIDS. Both ts1 and human immunodeficiency virus type 1 infect astrocytes, microglia, and oligodendrocytes but do not infect neurons. Oxidative stress has been implicated in the neuropathology of AIDS dementia and other neurodegenerative diseases. We report here that ts1 infection of astrocytes (both transformed C1 cells and primary cultures) also induces thiol (i.e., glutathione and cysteine) depletion and reactive oxygen species (ROS) accumulation, events occurring in parallel with viral envelope precursor gPr80env accumulation and upregulated expression of endoplasmic reticulum chaperones GRP78 and GRP94. Furthermore, ts1-infected astrocytes mobilize their thiol redox defenses by upregulating levels of the Nrf-2 transcription factor, as well its targets, the xCT cystine/glutamate antiporter, γ-glutamylcysteine ligase, and glutathione peroxidase. Depleting intracellular thiols by treating uninfected astrocytes with buthionine sulfoximine (BSO), a glutathione synthesis inhibitor, or by culturing in cystine-deficient medium, also induces ROS accumulation, activates Nrf-2, and upregulates Nrf-2 target gene expression in these astrocytes. Overexpression of Nrf-2 in astrocytes specifically increases expression of the above thiol synthesis-related proteins. Further treatment with BSO or N-acetylcysteine in transfected cells modulates this expression. Thiol depletion also accelerates cell death, while thiol supplementation promotes survival of ts1-infected cells. Together, our results indicate that ts1 infection of astrocytes, along with ts1-induced gPr80env accumulation, endoplasmic reticulum stress, thiol depletion, and oxidative stress, accelerates cell death; in response to the thiol depletion and oxidative stress, astrocytes activate their Nrf-2-mediated thiol antioxidant defenses, promoting cell survival.

Diet Quality as Measured by the Healthy Eating Index and the Association with Lipid Profile in Low-Income Women in Early Postpartum

Early postpartum is a critical period that may initiate consumption of an unhealthful diet, which can lead to obesity and adverse lipid profiles. The Healthy Eating Index 2005 (HEI 2005) is a tool that assesses diet quality in terms of adherence to the 2005 Dietary Guidelines for Americans. Previous versions of HEI have shown to be associated with serum lipids. The aim of this research is to evaluate the diet quality of women in early postpartum using the HEI 2005 and to examine the relationship of index scores with serum lipids and anthropometrics. A convenience sample of 125 multiethnic, overweight/obese women in early postpartum was recruited from urban clinics from June 2004 through April 2007. Dietary intake was measured via the average of a 24-hour dietary recall and 2-day food intake records. The HEI 2005 scores were computed to assess diet quality and were compared to anthropometrics and serum lipids. Descriptive statistics, analysis of covariance, and linear regression were utilized. This sample had low mean scores in fruits, total vegetables, whole grains, and oil components. Conversely, participants consumed more than recommended amounts of sodium, saturated fats, and discretionary calories. The HEI 2005 scores inversely predicted body mass index and low-density lipoprotein and total cholesterol, and positively predicted high-density lipoprotein cholesterol. Low-income women in early postpartum exhibited poor diet quality, as indicated by low total index scores. Further studies are warranted to identify appropriate dietary modifications in this population and to confirm the association of diet quality, as assessed by this HEI 2005 index, with lipids and other markers of health.

Development and validation of the eating stimulus index in low-income, minority women in early postpartum.

Dietary modification to achieve weight loss during the postpartum period may be critical for prevention of obesity, particularly in low-income, minority women. The aim of this cross-sectional study was to develop and validate a measure to examine motivations to eat in low-income, minority women during early postpartum. A convenience sample of 179 triethnic women was recruited from the Special Supplemental Program for Women, Infants, and Children clinics from June 2004 to April 2007. Subjects made one visit to a study center where they completed the Eating Stimulus Index and questions regarding individual demographic characteristics including ethnicity, age, income, education, marital status, breastfeeding, and employment status. Weight and height were also measured during this visit and used to calculate body mass index (BMI; calculated as kg/m(2)). An additional sample of 31 women completed the Eating Stimulus Index on two occasions with 2 weeks between to establish test-retest reliability. The factor structure of the scale was examined with principal components analysis. Total scale scores and subscale scores were calculated and Pearsons correlation and multiple regression analysis examined relationships to BMI. Principal component analysis produced an eight-factor structure with loadings >0.40. Cronbachs alpha coefficients for each subscale ranged from .54 to .89. Subscales of Convenience Eating, Emotional Eating, and Dietary Restraint were related to BMI in mothers. African-American, exclusively formula-feeding, and older women were most vulnerable to convenience eating. White women and those with the highest level of education were most vulnerable to emotional eating. The Eating Stimulus Index is a valid and reliable instrument with the ability to discriminate by weight. It can be used to assess motivations to eat in order to facilitate development of tailored weight-loss messages during early postpartum.

Validation of a 3-dimensional laser body scanner for assessment of waist and hip circumference.

Objectives: To evaluate the reliability and validity of a 3-dimensional laser body scanner for estimation of waist and hip circumferences and waist:hip ratio. Methods: Seventy women were evaluated for waist and hip circumference and waist∶hip ratio via laser scanner and tape measure. In a subset of 34 participants, 8 repeated measures of laser scanning were performed for reproducibility analysis. Validity of the instrument was assessed by regression and Bland-Altman comparison of measures of waist and hip circumferences and waist∶hip ratio to tape measure. Results: Reproducibility analysis showed little difference between within-subjects measurements of circumferences (intraclass correlation coefficient ≥0.992, p < 0.01). Evaluation of waist and hip circumferences measured by body scanning did not differ significantly from tape measure (p > 0.05). Bland-Altman analysis showed no bias between laser scanning and tape measure. Conclusion: These findings indicate that the 3-dimensional laser body scanner is a reliable and valid technique for the estimation of waist and hip circumferences as compared with tape measure. This instrument is promising as a quick and simple method of body circumference analysis.

Motivations to eat are related to diet quality and food intake in overweight and obese, low-income women in early postpartum

Healthful dietary practices and a return to prepregnancy weight are of significant importance in the prevention of obesity for women. The Eating Stimulus Index (ESI) was used to determine the relationship between motivations to eat and diet quality and food intake in 115 overweight/obese, low-income women in early postpartum. In this cross-sectional design, participants completed the ESI and food frequency questionnaire. Diet quality was assessed using the Dietary Guidelines Adherence Index. Diet quality was related to greater fruit and vegetable availability, convenience eating resistance, and vegetable taste preference. Women with high fruit and vegetable availability consumed more vegetables, as compared to those with low availability. High convenience eating resistance was associated with lower discretionary energy intakes. High taste preference for vegetables was related to greater intakes of these foods. Hierarchical regression analysis indicated that convenience eating resistance was the strongest predictor of diet quality followed by vegetable taste preference, and fruit and vegetable availability. Convenience eating resistance was also the strongest predictor of discretionary energy intake. In conclusion, women who were less vulnerable to environmental eating cues, had greater fruit and vegetable availability, and preferred the taste of vegetables consumed a more healthful diet. Thus, the ESI may be a useful screening tool for the design of personalized weight loss messages in the treatment of obesity.