Novel short-term effects of adenovirus Ad-36 on hamster lipoproteins.
OBJECTIVE
Human adenovirus Ad-36 induces adiposity and lowers total serum cholesterol in chickens, mice and marmosets and Ad-36 antibodies are associated with human obesity. We examined the early effects of Ad-36 inoculation on plasma cholesterol levels in hamsters fed a hyperlipidemic diet.


METHODS
A total of 32 male Golden Syrian hamsters were divided into two equal weight-matched groups and intranasally inoculated with Ad-36 (INF: infected) or media (CON: control). In each group, the animals were fed either a purified diet (PF, n=8) 40%en fat +/-194 mg cholesterol/1000 kcal or chow (C, n=8) ad libitum. Animals were killed 5 weeks postinoculation.


RESULTS
Nested PCR assay detected Ad-36 DNA in the lung, liver, visceral adipose tissue and skeletal muscle of the INF group, but not in the CON animals. Ad-36 antibodies were detected in the INF group only. For all animals, total plasma cholesterol (TC) was not significantly affected by Ad-36 treatment (203+/-92 vs 193+/-75 mg/dl, P=NS; INF vs CON, respectively). In 5 weeks, Ad-36 infection had no effect on TC concentration in hamsters fed chow (128+/-39 vs 130+/-27 mg/dl, INF-C vs CON-C, respectively) or those fed PF (269+/-70 vs 256+/-47 mg/dl, INF-P vs CON-P, respectively). However, lipoproteins isolated by density gradient ultracentrifugation showed a greater proportion of LDL cholesterol in INF animals, as compared to CON (28.4+/-1.6% vs 16.4+/-1.2%, P=0.02), regardless of dietary treatment (INF-P vs CON-P: 27.3+/-2.1 vs 15.7+/-1.5%, P=0.07; and INF-C vs CON-C: 29.4+/-1.2 vs 17.0+/-1.1%, P=0.009). This shift appears to be from HDL cholesterol to the LDL fractions.


CONCLUSIONS
These data suggest that in the hamster (a model resembling several aspects of human lipoprotein metabolism), Ad-36 infection may acutely affect the intravascular processing of lipoproteins resulting in a more atherogenic lipoprotein profile.
Kapila
M
M
Department of Nutrition and Food Science, Wayne State University, Detroit, MI 48202, USA.
Khosla
P
P
Dhurandhar
N V
NV
D000257:Adenoviridae Infections / Q000097:blood* / Q000473:pathology; D000260:Adenoviruses, Human / Q000254:growth & development / Q000302:isolation & purification; D000818:Animals; D001835:Body Weight; D002784:Cholesterol / Q000097:blood*; D006224:Cricetinae; D004032:Diet; D004195:Disease Models, Animal; D004435:Eating; D008074:Lipoproteins / Q000097:blood; D008297:Male; D008647:Mesocricetus
D008074:Lipoproteins; D002784:Cholesterol