Effect of dietary nucleosides and nucleotides on murine allergic rhinitis.

Although there are studies that report the effects of dietary nucleoside and nucleotide mixtures on the immune response, none are concerned with the role in allergic disease. This study evaluated the effect of dietary nucleic acid mixture (NAM) on mice with a nasal allergy model. One group of mice was supplemented with a 0.5% NAM and the other two groups were fed with a nucleic acid-free diet with 20% casein that served as sensitized and nonsensitized controls. The mice of the NAM group and the sensitized control group were sensitized in two courses by 2 microl of 5% 2,4-toluene diisocyanate (TDI), whereas the nonsensitized control was given 2 microl of ethylacetate instead of TDI. On the 28th day, an allergy was provoked with 4 microl of 2.5% TDI and the allergic responses were observed for 10 minutes. Results showed that the NAM diet group had more severe symptoms of itching, rhinorrhea, snorting, and irritability compared with the controls; also observed were a high incidence of sneezing at 34.7 +/- 4.0 in NAM compared with 19.0 +/- 3.0 (P < 0.001) in sensitized controls and 2.8 +/- 0.7 in nonsensitized controls. From this study, it can be concluded that diets supplemented with nucleic acid mixture contribute to the severity of murine allergic rhinitis.