Influence of adenovirus 36 seropositivity on the expression of adipogenic microRNAs in obese subjects.

BACKGROUND: Infection by Adenovirus 36 (Ad-36) has been associated with adipogenesis using cell and animal models, and a high risk of developing obesity has been reported in Ad-36-seropositive individuals. However, molecular mechanisms involved in the maintenance over the years of adipogenesis associated with Ad-36 has not been investigated in human adipose tissue. Epigenetic mechanisms, such as micro-RNAs (miRNAs) that regulate gene expression at the post-transcriptional level, have shown an important role in the development and maintenance of metabolic diseases. AIM: This study investigated the expression of miRNA associated with the adipogenic process in visceral adipose tissue from obese individuals according to Ad-36 serology. METHODS: Obese individuals were separated according to their status of Ad-36 serology in seropositive (Ad-36 (+); n = 29) and seronegative (Ad-36 (-); n = 28) groups. Additionally, a group of lean controls (n = 17) was selected to compare with obese individuals. Biopsies of visceral adipose tissue were obtained to evaluate miRNA and gene expression. The study of Ad-36 serology was carried out by ELISA. The expression of pro-adipogenic (miR-17 and miR-210) and anti-adipogenic (miR-155, miR-130 and miR-27a) miRNAs was evaluated using Taqman advanced miRNA assays by qPCR. The expression of adipogenes encoding LEP, ADIPOQ, and PPARγ was evaluated by Taqman predesigned assays through qPCR. RESULTS: The obese group had higher LEP (p < 0.001) and PPARγ (p = 0.016) expression and lower ADIPOQ expression (p = 0.017), and also had higher expression of miR-210 (p = 0.039), whereas lower expression of miR-155 (p = 0.019) and miR-27a (p = 0.028) as compared to lean controls. Higher PPARγ expression (p = 0.008), but no influence on LEP or ADIPOQ expression was observed in Ad-36 (+) group. Those seropositive individuals also had higher expression of the miR-17 (p = 0.028) and lower levels of miR-155 (p = 0.031) in adipose tissue as compared to seronegative subjects. CONCLUSIONS: Individuals with previous infection by Ad-36 had higher expression of the pro-adipogenic miR-17 and lower expression of the anti-adipogenic miR-155, which could lead to an increased adipogenic status by positively modulating PPARγ expression in adipose tissue from obese subjects.

Adenovirus 36 seropositivity is related to obesity risk, glycemic control, and leptin levels in Chilean subjects.

BACKGROUND: Adenovirus 36 (Ad-36) has been associated to adiposity in animal and in vitro studies. Ad-36 seropositivity has also been reported to contribute to obesity risk in children and adult populations. We investigated the relationship of Ad-36 serology with obesity and metabolic parameters in a Chilean population. SUBJECTS AND METHODS: Clinical and anthropometric data were obtained and blood samples were drawn from 99 lean (BMI: 18.5-24.9 kg/m2) and 151 obese (BMI > 30 kg/m2) subjects. Laboratory tests included lipid profile as well as glucose, insulin, leptin, and adiponectin levels. Ad-36 seropositivity was evaluated in serum samples by enzyme-linked immunosorbent assay. RESULTS: Seroprevalence of Ad-36 was higher in the obese group (58%) than in lean controls (34%) demonstrating that individuals previously infected with Ad-36 have higher risk of obesity in the study population (OR: 2.67, 95%CI: 1.58-4.51, p < 0.001). Interestingly, Ad-36 was related to lower concentrations of triglycerides and VLDL cholesterol in lean subjects (p = 0.049) and lower leptin in obese individuals (p = 0.014). Previous Ad-36 infection was also related to lower glycemia, insulinemia, and HOMA-IR (p < 0.05) in obese subjects who were not under antidiabetic drugs. CONCLUSIONS: Our results provide evidence of the contribution of previous Ad-36 infection to an increased risk of obesity in adult Chilean population. Ad-36 seropositivity was also associated to lipid profile, glycemic control, and leptin levels in adult Chilean population.

Healthy Lifestyle Fitness Camp: A Summer Approach to Prevent Obesity in Low-Income Youth.

OBJECTIVE: To examine the effect of participation in a summer camp focused on nutrition and fitness among low-income youth. METHODS: In 2011-2012, overweight and obese youth (n = 126) from Fresno, CA participated in a free 6-week summer program, Healthy Lifestyle Fitness Camp (HLFC), which included 3 h/wk of nutrition education provided by University of California CalFresh and 3 hours of daily physical activity through Fresno Parks and Recreation. The researchers used repeated-measures ANOVA to examine changes in weight, waist circumference, and waist-to-height ratio (WHtR) between HLFC and the comparison group (n = 29). RESULTS: Significant pre-post WHtR reductions were observed in HLFC: 0.64 to 0.61 (P < .001). In addition, WHtR reductions were maintained in HLFC 2 months afterward whereas an increase occurred in the comparison group (P < .007). CONCLUSIONS AND IMPLICATIONS: Understanding the impact of nutrition- and fitness-themed summer camps during unstructured months of summer is integral to obesity prevention among low-income youth.

Development and use of an evaluation tool for taste-testing activities by school-aged children.

We describe the development and application of a teacher-administered tool for routine program evaluation of food-tasting activities among low-income children and adolescents in a classroom or afterschool setting. This six-item evaluation tool is intended to capture student willingness to try new foods and ask for them at home. Phase 1 involved one-on-one interviews to determine the feasibility of the taste test tool among nine elementary school teachers in 2009 (168 students) and a validation pilot study in 2010 among 114 school-aged students participating in a University of California Supplemental Nutrition Assistance Program Nutrition Education (UC SNAP-Ed) summer program. Phase 2 determined instrument reliability and compared student response by grade level and food category in a convenience sample of 514 UC SNAP-Ed classrooms in 2010-2011. The mean proportion of the classroom ever having tried the foods before was 0.62 ± 0.33, and 0.77 ± 0.27 were willing to ask for the foods at home (P<0.0001). Compared with younger students (preschool through sixth grade), older students (seventh through 12th grade) were less likely to try the foods in class and less willing to try them again or ask for them at home (P<0.05). Students reported significantly greater previous exposure and willingness to try the food again for fruits than for vegetables (P<0.0001). A teacher-administered taste test tool is feasible to use in a group setting and capable of yielding valid, reliable information to evaluate student response and to guide SNAP-Ed program delivery.