Western diet changes cardiac acyl-CoA composition in obese rats: a potential role for hepatic lipogenesis.

The "lipotoxic footprint" of cardiac maladaptation in diet-induced obesity is poorly defined. We investigated how manipulation of dietary lipid and carbohydrate influenced potential lipotoxic species in the failing heart. In Wistar rats, contractile dysfunction develops at 48 weeks on a high-fat/high-carbohydrate "Western" diet, but not on low-fat/high-carbohydrate or high-fat diets. Cardiac content of the lipotoxic candidates--diacylglycerol, ceramide, lipid peroxide, and long-chain acyl-CoA species--was measured at different time points by high-performance liquid chromatography and biochemical assays, as was lipogenic capacity in the heart and liver by qRT-PCR and radiometric assays. Changes in membranes fluidity were also monitored using fluorescence polarization. We report that Western feeding induced a 40% decrease in myocardial palmitoleoyl-CoA content and a similar decrease in the unsaturated-to-saturated fatty acid ratio. These changes were associated with impaired cardiac mitochondrial membrane fluidity. At the same time, hepatic lipogenic capacity was increased in animals fed Western diet (+270% fatty acid elongase activity compared with high-fat diet), while fatty acid desaturase activity decreased over time. Our findings suggest that dysregulation of lipogenesis is a significant component of heart failure in diet-induced obesity.

Dietary factors in the modulation of inflammatory bowel disease activity.

CONTEXT: As patients look to complementary therapies for management of their diseases, it is important that the physician know the effectiveness and/or lack of effectiveness of a variety of dietary approaches/interventions. Although the pathogenesis of the inflammatory bowel diseases (ulcerative colitis and Crohn's disease) is not fully understood, many suspect that diet and various dietary factors may play a modulating role in the disease process. EVIDENCE ACQUISITION: The purpose of this article is to present some of what is known about various dietary/nutritional factors in inflammatory bowel disease, with inclusion of evidence from various studies regarding their putative effect. MedLINE was searched (1965-present) using combinations of the following search terms: diet, inflammatory bowel disease, Crohn's disease, and ulcerative colitis. Additionally, references of the articles obtained were searched to identify further potential sources of information. EVIDENCE SYNTHESIS: While much information is available regarding various dietary interventions/supplements in regard to inflammatory bowel disease, the lack of controlled trials limits broad applicability. Probiotics are one of the few interventions with promising results and controlled trials. CONCLUSION: While there are many potential and promising dietary factors that may play a role in the modulation of inflammatory bowel disease, it is prudent to await further controlled studies before broad application/physician recommendation in the noted patient population.

Western diet, but not high fat diet, causes derangements of fatty acid metabolism and contractile dysfunction in the heart of Wistar rats.

Obesity and diabetes are associated with increased fatty acid availability in excess of muscle fatty acid oxidation capacity. This mismatch is implicated in the pathogenesis of cardiac contractile dysfunction and also in the development of skeletal-muscle insulin resistance. We tested the hypothesis that 'Western' and high fat diets differentially cause maladaptation of cardiac- and skeletal-muscle fatty acid oxidation, resulting in cardiac contractile dysfunction. Wistar rats were fed on low fat, 'Western' or high fat (10, 45 or 60% calories from fat respectively) diet for acute (1 day to 1 week), short (4-8 weeks), intermediate (16-24 weeks) or long (32-48 weeks) term. Oleate oxidation in heart muscle ex vivo increased with high fat diet at all time points investigated. In contrast, cardiac oleate oxidation increased with Western diet in the acute, short and intermediate term, but not in the long term. Consistent with fatty acid oxidation maladaptation, cardiac power decreased with long-term Western diet only. In contrast, soleus muscle oleate oxidation (ex vivo) increased only in the acute and short term with either Western or high fat feeding. Fatty acid-responsive genes, including PDHK4 (pyruvate dehydrogenase kinase 4) and CTE1 (cytosolic thioesterase 1), increased in heart and soleus muscle to a greater extent with feeding a high fat diet compared with a Western diet. In conclusion, we implicate inadequate induction of a cassette of fatty acid-responsive genes, and impaired activation of fatty acid oxidation, in the development of cardiac dysfunction with Western diet.

Hormonal risk factors and testicular cancer

The cause of testicular cancer is not known and recent hypotheses have suggested an altered hormonal milieu may increase the risk of testis cancer. This study examined modulation of testicular cancer risk by hormonal factors, specifically: environmental xenoestrogens (e.g. organochlorines), prenatal maternal estrogens, testosterone indices (age at puberty, severe adolescent acne, self-reported balding), sedentary lifestyle and dietary consumption of fats and phytoestrogens.^ A hospital based friend matched case-control study was conducted at the University of Texas M. D. Anderson Cancer Center in Houston, Texas, between January 1990 and October 1996. Cases had a first primary testis tumor diagnosed between age 18 to 50 years and resided in Texas, Louisiana, Oklahoma or Arkansas.^ Cases and friend controls completed a mail questionnaire and case/control mothers were contacted by phone regarding pregnancy related variables. The study population comprised 187 cases, 148 controls, 147 case mothers and 86 control mothers. Odds ratios were virtually identical whether the match was retained or dissolved, thus the analyses were conducted using unconditional logistic regression.^ Cryptorchidism was a strong risk factor for testis cancer with an age-adjusted odds ratio (OR) of 7.7 (95% confidence interval (CI): 2.3-26.3). In a final model (adjusted for age, education, and cryptorchidism), history of severe adolescent acne and self-reported balding were both significantly protective, as hypothesized. For acne (yes vs. no) the OR was 0.5 (CI: 0.3-1.0) and for balding (yes vs. no) the OR was 0.6 (CI: 0.3-1.0). Marijuana smoking was a risk factor among heavy, regular users (17 times/week, OR = 2.4; CI: 0.9-6.4) and higher saturated fat intake increased testis cancer risk (saturated fat intake $>$ 15.2 grams/day vs. $<$ 11.8 grams/day, OR = 3.3; CI: 1.5-7.1). Early puberty, xenoestrogen exposure, elevated maternal estrogen levels, sedentary lifestyle and dietary phytoestrogen intake were not associated with risk of testicular cancer.^ In conclusion, testicular cancer may be associated with endogenous androgen metabolism although environmental estrogen exposure can not be ruled out. Further research is needed to understand the underlying hormonal mechanisms and possible dietary influences. ^

Estimated current patterns of food consumption and perceived changes among patients with lymphoma

Usual food choices during the past year, self-reported changes in consumption of three important food groups, and weight changes or stability were the questions addressed in this cross-sectional survey and retrospective review. The subjects were 141 patients with Hodgkin's disease or other B-cell types of lymphoma within their first three years following completion of initial treatments for lymphoma at the University of Texas M. D. Anderson Cancer Center in Houston, Texas. ^ The previously validated Block-98 Food Frequency Questionnaire was used to estimate usual food choices during the past year. Supplementary questions asked about changes breads and cereals (white or whole grain) and relative amounts of fruits and vegetables compared with before diagnosis and treatment. Over half of the subjects reported consuming more whole grains, fruits, and/or vegetables and almost three quarters of those not reporting such changes had been consuming whole grains before diagnosis and treatment. ^ Various dietary patterns were defined in order to learn whether proportionately more patients who changed in healthy directions fulfilled recognized nutritional guidelines such as 5-A-day fruits and vegetables and Dietary Reference Intakes (DRIB) for selected nutrients. ^ Small sizes of dietary pattern sub-groups limited the power of this study to detect differences in meeting recommended dietary guidelines. Nevertheless, insufficient and excessive intakes were detected among individuals with respect to fruits and vegetables, fats, calcium, selenium, iron, folate, and Vitamin A. The prevalence of inadequate or excess intakes of foods or nutrients even among those who perceived that they had increased or continued to eat whole grains and/or fruits and vegetables is of concern because of recognized effects upon general health and potential cancer related effects. ^ Over half of the subjects were overweight or obese (by BMI category) on their first visit to this cancer center and that proportion increased to almost three-quarters by their last follow-up visits. Men were significantly heavier than women, but no other significant differences in BMI measures were found even after accounting for prescribed steroids and dietary patterns. ^

Food advertisements during children's television programming in 2007: Comparison with ads in 1994 and the 2005 dietary recommendations

Childhood overweight and obesity are two major public health problems that are of economic and medical concern in the world today (Lobstein, Baur, & Uauy, 2004). Overweight conditions in childhood are important because they are widely prevalent, serious, and carry lifetime consequences for health and well being (Lobstein et al., 2004). Several studies have shown an association between television viewing and obesity in all age groups (Caroli, Argentieri, Cardone, & Masi, 2004; Harper, 2006; Vandewater & Huang, 2006; Wiecha et al., 2006). One mechanism that potentially links television viewing to childhood obesity is food advertising (Story, 2003). ^ The purpose of this study was to examine the types of foods advertised on children's television programming and to determine if there have been any changes in the number and types of commercials over the last 13 years. In addition, the food content of the advertisements was compared to the 2005 Dietary Guidelines to determine if the foods targeted were consistent with the current recommendations. Finally, each television network was analyzed individually to determine any differences between advertising on cable and regular programming. ^ A descriptive analysis was conducted on the most commonly advertised commercials during children's television programming on Saturday morning from 7 a.m. to 10:30 a.m. A total of 10 major television networks were viewed on three different Saturday mornings during June and July 2007. Commercial advertising accounted for approximately 19% of children's total viewing time. Of the 3,185 commercials, 28.5% were for foods, 67.7% were for non-food items, and 3.8% were PSAs. On average, there were 30 commercial advertisements and PSAs per hour, of which approximately nine were for food. ^ Of the 907 food advertisements, 72.0% were for foods classified in the fats, oils, and sugar group. The next largest group (17.3%) was for restaurant food of which 15.3% were for unhealthy/fast food restaurant fare. The most frequently advertised food product on Saturday morning television was regular cereal, accounting for 43.9% of all food advertisements. ^ Cable and regular programming stations varied slightly in the amount, length, and category of commercials. Cable television had about 50% less commercials and PSAs (1098) than regular programming (2087), but only had approximately 150 minutes less total commercial and PSA time; therefore, cable, in general, had longer commercials than regular programming. Overall, cable programming had more advertisements encouraging increased physical activity and positive nutrition behavior with less commercials focusing on the fats, oils, and sugar groups, compared to regular programming. ^ During the last 13 years, food advertisements have not improved, despite the recent IOM report on marketing foods to children (Institute of Medicine-Committee on Food Marketing and the Diets of Children and Youth, 2005), although the frequency of food advertisements has improved slightly. Children are now viewing an average of one food advertisement every 7 minutes, compared to one food advertisement every 5 minutes in 1994 (Kotz & Story, 1994). Therefore, manufacturers are putting a greater emphasis on advertising other products to children. Despite the recent attention to the issue of marketing unhealthy foods to children through television advertisements, not much progress has been noted since 1994. Further advocacy and regulatory issues concerning the content of advertisements during Saturday morning TV need to be explored. ^

Genetic variability and the hypothalamic control of energy balance

Background. Obesity is a major health problem throughout the industrialized world. Despite numerous attempts to curtail the rapid growth of obesity, its incidence continues to rise. Therefore, it is crucial to better understand the etiology of obesity beyond the concept of energy balance.^ Aims. The first aim of this study was to first investigate the relationship between eating behaviors and body size. The second goal was to identify genetic variation associated with eating behaviors. Thirdly, this study aimed to examine the joint relationships between eating behavior, body size and genetic variation.^ Methods. This study utilized baseline data ascertained in young adults from the Training Interventions and Genetics of Exercise (TIGER) Study. Variables assessed included eating behavior (Emotional Eating Scale, Eating Attitudes Test-26, and the Block98 Food Frequency Questionnaire), body size (body mass index, waist and hip circumference, waist/hip ratio, and percent body fat), genetic variation in genes implicated related to the hypothalamic control of energy balance, and appropriate covariates (age, gender, race/ethnicity, smoking status, and physical activity. For the genetic association analyses, genotypes were collapsed by minor allele frequency, and haplotypes were estimated for each gene. Additionally, Bayesian networks were constructed in order to determine the relationships between genetic variation, eating behavior and body size.^ Results. We report that the EAT-26 score, Caloric intake, percent fat, fiber intake, HEAT index, and daily servings of vegetables, meats, grains, and fats were significantly associated with at least one body size measure. Multiple SNPs in 17 genes and haplotypes from 12 genes were tested for their association with body size. Variation within both DRD4 and HTR2A was found to be associated with EAT-26 score. In addition, variation in the ghrelin gene (GHRL) was significantly associated with daily Caloric intake. A significant interaction between daily servings of grains and the HEAT index and variation within the leptin receptor gene (LEPR) was shown to influence body size.^ Conclusion. This study has shown that there is a substantial genetic component to eating behavior and that genetic variation interacts with eating behavior to influence body size.^

The relationship between supermarket nutrient movements and the mortality rates from fat-associated and non-fat-associated cardiovascular disease: Development of an ecologic method for determining community food patterns

Supermarket nutrient movement, a community food consumption measure, aggregated 1,023 high-fat foods, representing 100% of visible fats and approximately 44% of hidden fats in the food supply (FAO, 1980). Fatty acid and cholesterol content of foods shipped from the warehouse to 47 supermarkets located in the Houston area were calculated over a 6 month period. These stores were located in census tracts with over 50% of a given ethnicity: Hispanic, black non-Hispanic, or white non-Hispanic. Categorizing the supermarket census tracts by predominant ethnicity, significant differences were found by ANOVA in the proportion of specific fatty acids and cholesterol content of the foods examined. Using ecological regression, ethnicity, income, and median age predicted supermarket lipid movements while residential stability did not. No associations were found between lipid movements and cardiovascular disease mortality, making further validation necessary for epidemiological application of this method. However, it has been shown to be a non-reactive and cost-effective method appropriate for tracking target foods in populations of groups, and for assessing the impact of mass media nutrition education, legislation, and fortification on community food and nutrient purchase patterns. ^

Mexico: A new heavy weight in a global world

In the last three decades, obesity has been gaining recognition as a serious public health problem in Mexico. This epidemic developed insidiously in a country that was still focused on chronic under-nutrition in the population. During that same period, macro-economic reforms projected Mexico into the global economic arena. Foreign investments, trade in goods and services, and technological transfers were promoted through participation in numerous trade agreements between Mexico and other countries. The North American Trade Agreement (NAFTA), signed in 1994, promised an integrated market between the three North American countries: Canada, the United States, and Mexico. Although these trade policies were likely to have effects on the available food supply in Mexico, this association has not been elucidated. In this case study, we examine how these trade liberalization policies may have influenced the food supply in Mexico.^ Information on the trade of food commodities between the United States and Mexico and the nature of foreign investment in Mexico was compiled using public data available through American, Mexican, and other international published reports for 1986 through 2011. After the implementation of NAFTA, an increase in trade and investments was observed between Mexico and its two North American partners, but most of the trade increase occurred between the US and Mexico. Since the liberalization of trade policies between these counties, exports of fruit and vegetables into the U.S. from Mexico have increased, while exports of cereals, fats, vegetable oils, meat, dairy products and processed foods from the U.S. into Mexico have increased. During this same time period, there has been an increase in the foreign direct investment in the food industry in Mexico, as well as changes in the types and amounts of dietary energy available on a population level. Specifically, between 1990 to 2006, the dietary energy supply per person has increased 6.1% available animal protein has increased 35.8%, and available fat has increased 18.9%.^ Thus, this case study suggests that the recent changes in food-related industries through foreign direct investment and market liberalization may be likely contributors to the obesogenic food environment in Mexico. Although this initial case study provides interesting data, whether trade liberalization policies should be considered hazardous for health as a distal determinant of the obesity epidemic needs to be further examined using a more stringent study design or further follow up of the US Mexico trade data.^