Purpose:
To examine the effects of diets enriched with n-3 and n-6 polyunsaturatedfatty acids (PUFAs) in a murine model of herpetic chorioretinitis.
Methods:
BALB/c mice were fed on high-fat diets which contained Menhadenoil (rich in n-3 PUFAs) (diet 1), Safflower oil (rich in n-6PUFAs) (diet 2), or Corn oil as control(diet 3), 14 days previouslyand 12 days following anterior chamber (AC) HSV-1 inoculation.After 14 days of treatment and before infection, splenic cellproliferation was evaluated as well as cytokines synthesis onculture supernatants.Development of chorioretinitis and encephalitiswas followed-up by clinical and histological signs. On day 12p.i. mice were sacrificed. Both eyes and brain were obtainedfor viral titration and RT-PCR analysis.
Results:
Mice fed on Menhaden oil experimented a decreased synthesisof TNF-α, IFN-γ, IL-2 and IL-10 in splenic cells isolated andstimulated by Con-A. Post HSV-1 inoculation, mice fed on Menhadenoil showed clinical and histological signs of chorioretinitisin both eyes and encephalitis. Moreover, high titers of viruswere recovered in ocular and brain tissue homogenates.
Conclusions:
Our findings indicate that mice fed on fish oil have impairedTh-1 immune respons which could lead to increased virus titersand consequent development of encephalitis and chorioretinisin both eyes. We also conclude that small but detectable amountsof virus (1x10(4) PFU/ml) could be present at uninoculated eyeswithout clinical and histopathological evidence of retinitis.It suggests that the triggering of retinal injury should requirea critical threshold of virus.
Keywords: uveitis-clinical/animal model • pathology: experimental • inflammation