Query: adenovirus 36

Relevant passages:
Association of Adenovirus 36 Infection with Obesity and Metabolic Markers in Humans: A Meta-Analysis of Observational Studies <=SEP=> Background Several studies have shown that Adenovirus 36 (Ad36) influences the risk of obesity in humans. Clarifying the relationship between Ad36 infection and obesity could lead to more effective approaches for the management of obesity. The objective of this study was to conduct a meta-analysis to confirm the influence of Ad36 infection on obesity and metabolic markers. Methodology/Principal Findings We searched MEDLINE and the Cochrane Library for pertinent articles (including their references) published between 1951 and April 22, 2012. Only English language reports of original observational studies were included in this meta-analysis. Data extraction was performed independently by two reviewers. Weighted mean differences (WMDs) and pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated using the random effects model. Of 237 potentially relevant studies, 10 cross-sectional studies (n = 2,870) conformed to the selection criteria. Pooled analysis showed that the WMD for BMI of Ad36 infection compared with non-infection was 3.19 (95% CI 1.44–4.93; P<0.001). Sensitivity analysis restricted to studies of adults yielded a similar result of 3.18 (95% CI 0.78–5.57; P = 0.009). The increased risk of obesity associated with Ad36 infection was also significant (OR: 1.9; 95% CI: 1.01–3.56; P = 0.047). No significant differences were found in relation to total cholesterol (P = 0.83), triglycerides (P = 0.64), HDL (P = 0.69), blood glucose (P = 0.08), waist circumstance (P = 0.09), and systolic blood pressure (P = 0.25). Conclusion/Significance Ad36 infection was associated with the risk of obesity and weight gain, but was not associated with abnormal metabolic markers including waist circumstance. It suggests that Ad36 infection is more associated with accumulation of subcutaneous fat than that of visceral fat. The relationship between Ad36 and obesity should be assessed by further studies, including well-designed prospective studies, to gain a better understanding of whether Ad36 plays a role in the etiology of human obesity.

Comparative genome analysis with the human genome reveals chicken genes associated with fatness and body weight. <=SEP=> The selection of meat-type chickens (broilers) for rapid growth has been accompanied by excessive fat deposition. In this study, we analysed 53 candidate genes that are associated with obesity and obesity-related traits in humans, for which we found chicken orthologues by BLAST searches. We have identified single nucleotide polymorphisms (SNPs) with significant differences in allele frequencies between broilers and layers in each of the following six candidate genes: adrenergic, beta-2-, receptor, surface (ADRB2); melanocortin 5 receptor (MC5R); leptin receptor (LEPR), McKusick-Kaufman syndrome (MKKS), milk fat globule-EGF factor 8 protein (MFGE8) and adenylate kinase 1 (AK1). To examine associations with fatness and/or body weight, we used birds of extreme phenotypes in F(2) and backcross populations with varying levels of abdominal fat weight per cent (%AFW) and body weight. We then assessed the level of gene expression by real-time PCR. In two genes, ADRB2 and MFGE8, we found significant association with %AFW. The ADRB2 gene was found to have a significantly higher expression in the liver of lean chickens compared with those of the fat individuals. We believe that this approach can be applied for the identification of other quantitative genes. © 2011 The Authors, Animal Genetics © 2011 Stichting International Foundation for Animal Genetics.

Adenovirus 36 infection and obesity. <=SEP=> The most important factors leading to fat accumulation in children are genetic inheritance, endocrine alterations, and behavioural/environmental causes. In addition, experimental animal studies have shown that infections due to various pathogens can lead to overweight and obesity conditions, and studies of humans have found that the incidence of seroconversion against some of these may be significantly more frequent in obese adults and children than in normal subjects. However, the results of these studies are not conclusive and, in some cases, have raised more questions than answers. We reviewed the literature concerning the role of adenovirus 36 (AD-36), the most widely studied infectious agent in animals and humans, because of its potential association with childhood obesity. The available evidence suggests that more studies are needed to evaluate whether or not the association between the presence of AD-36 antibodies and obesity is simply unrelated, and to verify whether there are subjects that have greater tendency to become obese because more easily susceptible to AD-36 infection or with a predisposition to suffer from persistent viral infection more easily leading to the development of obesity. If it is demonstrated that AD-36 does play a role in obesity, it will be important to investigate possible vaccines against the infection itself or antiviral drugs capable of inhibiting disease progression. Copyright © 2012 Elsevier B.V. All rights reserved.

Adipogenic Human Adenovirus Ad-36 Induces Commitment, Differentiation, and Lipid Accumulation in Human Adipose-Derived Stem Cells <=SEP=> Human adenovirus Ad-36 is causatively and correlatively linked with animal and human obesity, respectively. Ad-36 enhances differentiation of rodent preadipocytes, but its effect on adipogenesis in humans is unknown. To indirectly assess the role of Ad-36-induced adipogenesis in human obesity, the effect of the virus on commitment, differentiation, and lipid accumulation was investigated in vitro in primary human adipose-derived stem/stromal cells (hASC). Ad-36 infected hASC in a time- and dose-dependent manner. Even in the presence of osteogenic media, Ad-36-infected hASC showed significantly greater lipid accumulation, suggestive of their commitment to the adipocyte lineage. Even in the absence of adipogenic inducers, Ad-36 significantly increased hASC differentiation, as indicated by a time-dependent expression of genes within the adipogenic cascade—CCAAT/Enhancer binding protein-β, peroxisome proliferator-activated receptor-γ, and fatty acid-binding protein—and consequentially increased lipid accumulation in a time- and viral dose-dependent manner. Induction of hASC to the adipocyte state by Ad-36 was further supported by increased expression of lipoprotein lipase and the accumulation of its extracellular fraction. hASC from subjects harboring Ad-36 DNA in their adipose tissue due to natural infection had significantly greater ability to differentiate compared with Ad-36 DNA-negative counterparts, which offers a proof of concept. Thus, Ad-36 has the potential to induce adipogenesis in hASC, which may contribute to adiposity induced by the virus.

Adenovirus-36 Is Associated with Obesity in Children and Adults in Sweden as Determined by Rapid ELISA <=SEP=> Background Experimental and natural human adenovirus-36 (Adv36) infection of multiple animal species results in obesity through increasing adipogenesis and lipid accumulation in adipocytes. Presence of Adv36 antibodies detected by serum neutralization assay has previously been associated with obesity in children and adults living in the USA, South Korea and Italy, whereas no association with adult obesity was detected in Belgium/the Netherlands nor among USA military personnel. Adv36 infection has also been shown to reduce blood lipid levels, increase glucose uptake by adipose tissue and skeletal muscle biopsies, and to associate with improved glycemic control in non-diabetic individuals. Principal Findings Using a novel ELISA, 1946 clinically well-characterized individuals including 424 children and 1522 non-diabetic adults, and 89 anonymous blood donors, residing in central Sweden representing the population in Stockholm area, were studied for the presence of antibodies against Adv36 in serum. The prevalence of Adv36 positivity in lean individuals increased from ∼7% in 1992–1998 to 15–20% in 2002–2009, which paralleled the increase in obesity prevalence. We found that Adv36-positive serology was associated with pediatric obesity and with severe obesity in females compared to lean and overweight/mildly obese individuals, with a 1.5 to 2-fold Adv36 positivity increase in cases. Moreover, Adv36 positivity was less common among females and males on antilipid pharmacological treatment or with high blood triglyceride level. Insulin sensitivity, measured as lower HOMA-IR, showed a higher point estimate in Adv36-positive obese females and males, although it was not statistically significant (p = 0.08). Conclusion Using a novel ELISA we show that Adv36 infection is associated with pediatric obesity, severe obesity in adult females and lower risk of high blood lipid levels in non-diabetic Swedish individuals.

Modern organic and broiler chickens sold for human consumption provide more energy from fat than protein. <=SEP=> OBJECTIVE: In 1976, the Royal College of Physicians and the British Cardiac Society recommended eating less fatty red meat and more poultry instead because it was lean. However, the situation has changed since that time, with a striking increase in fat content of the standard broiler chicken. The aim of the present study was to report a snapshot of data on fat in chickens now sold to the public. DESIGN: Samples were obtained randomly between 2004 and 2008 from UK supermarkets, farm shops and a football club. The amount of chicken fat was estimated by emulsification and chloroform/methanol extraction. SETTING: Food sold in supermarkets and farms in England. SUBJECTS: Chicken samples. RESULTS: The fat energy exceeded that of protein. There has been a loss of n-3 fatty acids. The n-6:n-3 ratio was found to be as high as 9:1, as opposed to the recommendation of about 2:1. Moreover, the TAG level in the meat and whole bird mostly exceeded the proportion of phospholipids, which should be the higher for muscle function. The n-3 fatty acid docosapentaenoic acid (DPA, 22 : 5n-3) was in excess of DHA (22 : 6n-3). Previous analyses had, as usual for birds, more DHA than DPA. CONCLUSIONS: Traditional poultry and eggs were one of the few land-based sources of long-chain n-3 fatty acids, especially DHA, which is synthesized from its parent precursor in the green food chain. In view of the obesity epidemic, chickens that provide several times the fat energy compared with protein seem illogical. This type of chicken husbandry needs to be reviewed with regard to its implications for animal welfare and human nutrition.

Longitudinal changes in BMI in older adults are associated with meat consumption differentially, by type of meat consumed. <=SEP=> Hypotheses regarding the role of meat consumption in body weight modulation are contradictory. Prospective studies on an association between meat consumption and BMI change are limited. We assessed the association between meat consumption and change in BMI over time in 3902 men and women aged 55-69 y from the Netherlands Cohort Study. Dietary intake was estimated at baseline using a FFQ. BMI was ascertained through baseline self-reported height (1986) and weight (1986, 1992, and 2000). Analyses were based on sex-specific categories of daily total fresh meat, red meat, beef, pork, minced meat, chicken, processed meat, and fish consumption at baseline. Linear mixed effect modeling adjusted for confounders was used to assess longitudinal associations. Significant cross-sectional differences in BMI between quintiles of total meat intake were observed (P-trend < 0.01; both sexes). No association between total fresh meat consumption and prospective BMI change was observed in men (BMI change highest vs. lowest quintile after 14 y: -0.06 kg/m²; P = 0.75) and women (BMI change: 0.26 kg/m²; P = 0.20). Men with the highest intake of beef experienced a significantly lower increase in BMI after 6 and 14 y than those with the lowest intake (BMI change after 14 y 0.60 kg/m²). After 14 y, a significantly higher increase in BMI was associated with higher intakes of pork in women (BMI change highest vs. lowest quintile: 0.47 kg/m²) and chicken in both sexes (BMI change highest vs. lowest category in both men and women: 0.36 kg/m²). The results remained similar when stratifying on median baseline BMI, and age-stratified analyses yielded mixed results. Differential BMI change effects were observed for several subtypes of meat. However, total meat consumption, or factors directly related to total meat intake, was not strongly associated with weight change during the 14-y prospective follow-up in this elderly population.

A framework for identification of infections that contribute to human obesity. <=SEP=> WHO has declared obesity to be a global epidemic. Obesity management strategies mainly target behavioural components of the disorder, but are only marginally effective. A comprehensive understanding of the causative factors of obesity might provide more effective management approaches. Several microbes are causatively and correlatively linked with obesity in animals and human beings. If infections contribute to human obesity, then entirely different prevention and treatment strategies and public health policies could be needed to address this subtype of the disorder. Ethical reasons preclude experimental infection of human beings with candidate microbes to unequivocally determine their contribution to obesity. As an alternative, the available information about the adipogenic human adenovirus Ad36 has been used to create a template that can be used to examine comprehensively the contributions of specific candidate microbes to human obesity. Clinicians should be aware of infectobesity (obesity of infectious origin), and its potential importance in effective obesity management. Copyright © 2011 Elsevier Ltd. All rights reserved.

Human adenovirus-36 and childhood obesity. <=SEP=> There is increasing evidence that obesity in humans is associated with infection with human adenovirus-36 (Adv36). Infection of experimental animals with Adv36 demonstrates that this virus causes obesity. Human studies have shown a prevalence of Adv36 infection of 30% or greater in obese adult humans, but a correlation with obesity has not always been demonstrated. In contrast, three published studies and one presented study with a total of 559 children all show that there is an increase in prevalence of Adv36 infection in obese children (28%) compared to non-obese children (10%). The explanation for the apparently more robust correlation of Adv36 infection with obesity in children vs. adults is not clear. The data in animals and people suggests that Adv36 has contributed to the worldwide increase in childhood obesity. More research is needed to identify prevalences and consequences of Adv36 infection in people of all age groups and geographic locations.

Association of adenovirus infection with human obesity. <=SEP=> We previously reported that chickens infected with the avian adenovirus SMAM-1 developed a unique syndrome characterized by excessive intra-abdominal fat deposition accompanied by paradoxically low serum cholesterol and triglyceride levels. There have been no previous reports of avian adenoviruses infecting humans. We screened the serum of 52 humans with obesity in Bombay, India, for antibodies against SMAM-1 virus using the agar gel precipitation test (AGPT) method. Bodyweights and serum cholesterol and triglyceride levels were compared in SMAM-1-positive (P-AGPT) and SMAM-1-negative (N-AGPT) groups. Ten subjects were positive for antibodies to SMAM-1, and 42 subjects did not have antibodies. The P-AGPT group had a significantly higher bodyweight (p < 0.02) and body mass index (p < 0.001) (95.1 +/- 2.1 kg and 35.3 +/- 1.5 kg/m2, respectively) compared with the N-AGPT group (80.1 +/- 0.6 kg and 30.7 +/- 0.6 kg/m2, respectively). Also, the P-AGPT group had significantly lower serum cholesterol (p < 0.02) and triglyceride (p < 0.001) values (4.65 mmol/L and 1.45 mmol/L, respectively) compared with the N-AGPT group (5.51 mmol/L and 2.44 mmol/L, respectively). Two subjects positive for SMAM-1 antibodies had antibodies against each others' serum, suggesting the presence of antigens in one or both. When these two serum samples were inoculated into chicken embryos, macroscopic lesions compatible with SMAM-1 infection developed. The inoculation of serum from N-AGPT subjects did not produce such lesions. The presence of increased obesity, antibodies to SMAM-1, reduced levels of blood lipids, and viremia that produces a typical infection in chicken embryos suggests that SMAM-1, or a serologically similar human virus, may be involved in the cause of obesity in some humans.

Long-Term Changes in Adiposity and Glycemic Control Are Associated With Past Adenovirus Infection <=SEP=> OBJECTIVE Ad36, a human adenovirus, increases adiposity but improves glycemic control in animal models. Similarly, natural Ad36 infection is cross-sectionally associated with greater adiposity and better glycemic control in humans. This study compared longitudinal observations in indices of adiposity (BMI and body fat percentage) and glycemic control (fasting glucose and insulin) in Ad36-infected versus uninfected adults. RESEARCH DESIGN AND METHODS Baseline sera from Hispanic men and women (n = 1,400) were screened post hoc for the presence of Ad36-specific antibodies. Indices of adiposity and glycemic control at baseline and at ∼10 years past the baseline were compared between seropositive and seronegative subjects, with adjustment for age and sex. In addition to age and sex, indices of glycemic control were adjusted for baseline BMI and were analyzed only for nondiabetic subjects. RESULTS Seropositive subjects (14.5%) had greater adiposity at baseline, compared with seronegative subjects. Longitudinally, seropositive subjects showed greater adiposity indices but lower fasting insulin levels. Subgroup analyses revealed that Ad36-seropositivity was associated with better baseline glycemic control and lower fasting insulin levels over time in the normal-weight group (BMI ≤25 kg/m2) and longitudinally, with greater adiposity in the overweight (BMI 25–30 kg/m2) and obese (BMI >30 kg/m2) men. Statistically, the differences between seropositive and seronegative individuals were modest in light of the multiple tests performed. CONCLUSIONS This study strengthens the plausibility that in humans, Ad36 increases adiposity and attenuates deterioration of glycemic control. Panoptically, the study raises the possibility that certain infections may modulate obesity or diabetes risk. A comprehensive understanding of these under-recognized factors is needed to effectively combat such metabolic disorders.

Intake of total, animal and plant protein and subsequent changes in weight or waist circumference in European men and women: the Diogenes project. <=SEP=> BACKGROUND: As protein is considered to increase thermogenesis and satiety more than other macronutrients, it may have beneficial effects on prevention of weight gain and weight maintenance. OBJECTIVE: The objective of this study is to assess the association between the amount and type of dietary protein, and subsequent changes in weight and waist circumference (WC). METHODS: 89,432 men and women from five countries participating in European Prospective Investigation into Cancer and Nutrition (EPIC) were followed for a mean of 6.5 years. Associations between the intake of protein or subgroups of protein (from animal and plant sources) and changes in weight (g per year) or WC (cm per year) were investigated using gender and centre-specific multiple regression analyses. Adjustments were made for other baseline dietary factors, baseline anthropometrics, demographic and lifestyle factors and follow-up time. We used random effect meta-analyses to obtain pooled estimates across centres. RESULTS: Higher intake of total protein, and protein from animal sources was associated with subsequent weight gain for both genders, strongest among women, and the association was mainly attributable to protein from red and processed meat and poultry rather than from fish and dairy sources. There was no overall association between intake of plant protein and subsequent changes in weight. No clear overall associations between intakes of total protein or any of the subgroups and changes in WC were present. The associations showed some heterogeneity between centres, but pooling of estimates was still considered justified. CONCLUSION: A high intake of protein was not found associated with lower weight or waist gain in this observational study. In contrast, protein from food items of animal origin, especially meat and poultry, seemed to be positively associated with long-term weight gain. There were no clear associations for waist changes.

Human adenovirus-36 antibody status is associated with obesity in children. <=SEP=> BACKGROUND: Human adenovirus-36 (Ad-36) is thought to induce obesity by a direct effect of the viral E4orf1 gene on lipogenic enzymes in host adipocytes. Ad-36 prevalence is 30% in obese adults, but prevalence has not been reported in childhood obesity. OBJECTIVES: To determine the prevalence of Ad-36 infection in obese Korean children (age 14.8 +/- 1.9; range 8.3-6.3 years); correlation of infection with BMI z-score and other obesity measures. METHODS: Blood was drawn at the annual school physical exam or clinic visit; Ad-36 status was determined by serum neutralization assay; and routine serum chemistry values. RESULTS: A total of 30% of subjects were positive (N = 25) for Ad-36; 70% were negative (N = 59). Significantly higher BMI z-scores (1.92 vs. 1.65, p < 0.01) and waist circumferences (96.3 vs. 90.7 cm, p = 0.05) were found in infected versus uninfected children. Cardiovascular risk factors were not significantly different. CONCLUSIONS: Ad-36 infection is common in obese Korean children and correlates highly with obesity. Ad-36 may have played a role in the obesity and Type 2 diabetes epidemic in children.

Effect of adenovirus infection on adiposity in chicken. <=SEP=> Excessive fat accumulation has been observed in the field in chickens infected with adenovirus. In the present study this has been verified under experimental conditions. Chickens inoculated with adenovirus showed lesser weight gain but excessive adiposity compared to normal control chickens. These changes could not be explained by variation in food consumption. Chickens acquiring adenovirus naturally from the inoculated group showed similar adiposity. Serum cholesterol and triglyceride levels of inoculated and naturally infected chickens were significantly lower compared to those of the control group. Such an association between adenovirus infection and adiposity has been shown, probably, for the first time, which might help in further understanding of the complex problem of obesity.

Transmissibility of adenovirus-induced adiposity in a chicken model. <=SEP=> BACKGROUND: We previously reported that human adenovirus Ad-36 induces adiposity and paradoxically lower levels of serum cholesterol (CHOL) and triglycerides (TG) in animals. OBJECTIVE: To evaluate the transmissibility of Ad-36 and Ad-36 induced adiposity using a chicken model. DESIGN: Experiment 1--four chickens were housed (two per cage) and one from each cage was inoculated with Ad-36. Duration of presence of Ad-36 DNA in the blood of all chickens was monitored. Experiment 2--two groups of chickens were intranasally inoculated with Ad-36 (infected donors, I-D) or media (control donors, C-D). Blood drawn 36 h later from I-D and C-D groups was inoculated into wing veins of recipient chickens (infected receivers, I-R, and control receivers, C-R, respectively). On sacrifice, 5 weeks post-inoculation, blood was drawn, body weight noted and visceral fat was separated and weighed. RESULTS: Experiment 1--Ad-36 DNA appeared in the blood of the inoculated chickens and that of uninoculated chickens (cage mates) within 12 h of inoculation and the viral DNA persisted up to 25 days in the blood. Experiment 2--compared with C-D, visceral and total body fat were significantly greater and CHOL significantly lower for the I-D and I-R. TG were significantly lower for the I-D. Ad-36 was isolated from 12 out of 16 blood samples of the I-D that were used for inoculating I-R chickens. Ad-36 DNA was present in the blood and the adipose tissue of the I-D and I-R but not in the skeletal muscles of animals selected randomly for testing. CONCLUSION: As seen in experiment 1, Ad-36 infection can be transmitted horizontally from an infected chicken to another chicken sharing the cage. Additionally, experiment 2 demonstrated blood-borne transmission of Ad-36-induced adiposity in chickens. Transmissibility of Ad-36-induced adiposity in chicken model raises serious concerns about such a possibility in humans that needs further investigation.