Abstracts Infectious Obesity

New Page 18

Abstracts and News on Obesity Virus


Abstracts Titles    
Infectobesity: obesity of infectious origin.
Association of adenovirus infection with human obesity
Alteration of the Leptin Network in Late Morbid Obesity Induced in Mice by Brain Infection with Canine Distemper Virus

News Links

Doctors Guide: Virus May Be Linked to Obesity


Infectobesity: Obesity of Infectious Origin  

(Journal of Nutrition. 2001;131:2794S-2797S.)

Dhurandhar NV. The Department of Nutrition and Food Science and the Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48202, USA.

In the U.S., the prevalence of obesity increased by 30% from 1980 to 1990, and this increase appears to be continuing. Although obesity has multiple etiologies, an overlooked possibility is obesity of an infectious origin. Six pathogens are reported to cause obesity in animals. Canine distemper virus was the first virus reported to cause obesity in mice, followed by Rous-associated virus-7, an avian retrovirus, which has been shown to cause stunting, obesity and hyperlipidemia in chickens. Next, the obesity-promoting effect of Borna disease virus was demonstrated in rats. Scrapie agents were reported to induce obesity in mice and hamsters. The final two reports were of SMAM-1, an avian adenovirus, and Ad-36, a human adenovirus that caused obesity in animals. Additionally, an association with human obesity is the unique feature of SMAM-1 and Ad-36. Although the exact mechanism of pathogen-induced obesity is unclear, infection attributable to certain organisms should be included in the long list of potential etiological factors for obesity. In addition, the involvement of some pathogens in etiology of obesity suggests the possibility of a similar role for additional pathogens. Publication Types: Review Review, Tutorial PMID: 11584109 [PubMed - indexed for MEDLINE]


Association of adenovirus infection with human obesity

Obesity Research 5: 464-469 (1997)

V Dhurandhar, PR Kulkarni, SM Ajinkya, AA Sherikar and RL Atkinson Department of Medicine, University of Wisconsin, Madison 53706, USA.

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.


Alteration of the Leptin Network in Late Morbid Obesity Induced in Mice by Brain Infection with Canine Distemper Virus  

Biotherapy 1996;9(1-3):87-90

De Vinci C, Levine PH, Pizza G, Fudenberg HH, Orens P, Pearson G, Viza D.

Viruses can induce progressive neurologic disorders associated with diverse pathological manifestations, and therefore, viral infection of the brain can impair differentiated neural functions, depending on the initial viral tropism. We have previously reported that canine distemper virus (CDV) targets certain mouse brain structures, including the hypothalamus, early and selectively. Infected mice exhibit acute encephalitis, with late disease, characterized by motor impairment or obesity syndrome, appearing in some of the surviving mice several months after the initial viral replication. In the present study, we show viral persistence in the hypothalami of obese mice, as demonstrated by low, but still significant, levels of CDV nucleoprotein transcripts, associated with a dramatic decrease in F gene mRNAs. Given the pivotal role of the hypothalamus in obesity (eating behavior, energy consumption, and neuroendocrine function) and that of leptin, the adipose tissue-derived satiety factor acting through hypothalamic receptors, we analyzed the leptin networks in both obese and nonobese mice. The discrepancy found between the chronic and dramatic increase in blood leptin levels and the occurrence of obesity may be due to leptin resistance in the brain. In fact, expression of the long leptin receptor isoform, representing the functional leptin receptor, was specifically downregulated in the hypothalami of obese mice, explaining their inability to generate an adequate response to leptin in the brain. Intriguingly, during the acute phase of infection, its expression was increased in CDV-targeted structures in all infected mice and remained high in obese mice in all CDV-targeted structures, except for the hypothalamus. The biphasic change in hypothalamic leptin receptor expression seen during the progression of CDV-induced obesity provides a new paradigm for understanding mechanisms of neuroendocrinological, virus-induced abnormalities.

Learn how nutritional science can change your life

Subscribe for benefits that are only available to our subscribers.

• New product updates
• New discounts
• Corporate news
• Distributor information
• Information about nutrition
• Lifestyles
* indicates required

Dietary Nutritional Supplements | ShapeRite Weight Management with Nutritional Supplements | Health Vitamins Supplements | Adult Stem Cell Support | 4Life Transfer Factor Immune Support | Intestinal Cleanse Detox | Antioxidants - Acai Berry Juice | Herbal Dietary Nutritional Products