0908 Adenovirus as a cause of obesity

Perhaps the currently best known association between an infection and fat metabolism is that of lipodystrophy with HIV infection. However there is another that is receiving attention and that is the association between adenovirus infection and obesity. Over the past decade work emanating from Dhurandar’s laboratory in the USA has shown that human adenovirus-36 (Ad-36) induces adiposity in experimentally-infected chickens, mice and non-human primates. The virus does this by increasing replication, differentiation, lipid accumulation and insulin sensitivity in fat cells, and by reducing the fat cells’ leptin secretion and expression. Ad-36 also acts at the primary preadipocyte level where it has been shown that the virus is capable of inducing the adipogenic cascade in the absence of adipogenic media i.e. it is an exogenous regulator of the adipogenic process. Beyond showing that a human adenovirus is capable of infecting animals and affecting adipogenesis it has also been shown in a study population that 30% of obese subjects have antibodies to Ad-36 vs 11% of controls. This suggests a) there is indeed an association between obesity and the virus, and b) that there are likely other factors that ‘protect’ the non-obese or expose some of the obese to the effects of the virus. What also needs to be answered is whether the adipogenic effects are permanent i.e. there is clearly an acute effect of infection but humans typically eliminate adenovirus in other situations (e.g. with ophthalmic, respiratory and gastrointestinal infection) – does the same apply to this infection? Nobody is suggesting anything other than Ad-36 possibly being added to the list of causes of obesity, but there is also the possibility that elucidation of the molecular pathways involved may lead to novel treatments and interventions for obesity.

Read more:
Obesity (Silver Spring) 2009 Jan 22; Epub ahead of print
Arch Virol 2008; 153: 2097-2102
Drug News Perspect 2004; 17: 307-13