Photoprotection prevents TPN-induced lung procollagen mRNA in newborn guinea pigs.

BACKGROUND

Photo-exposed intravenous multivitamin solutions (MVP) carry a peroxide load. Peroxidation induces gene expression of procollagen. We hypothesized that photo exposure of the MVP solution might promote pulmonary fibrosis. The aim of the study was to assess the potential for MVP to increase procollagen mRNA.

METHODS

Three day old guinea pigs were assigned to the following intravenous regimens, either: Control (C): 5% dextrose + 0.45% NaCl; C + 200 or 500 microM H(2)O(2); C + 500 microM H(2)O(2) + 10 microM GSSG; [C + 1% MVP +/- [amino acids + lipids]] +/- photoprotected. After 4 d, levels of pulmonary alpha1(I) procollagen mRNA and glutathione were determined. Results were compared by ANOVA.

RESULTS

Photoprotection of MVP or TPN prevents light induction of procollagen mRNA. The effect of MVP + light was associated with a peroxide load coupled with a low glutathione level. This was also observed with the 500 microM H(2)O(2) group. The addition of GSSG prevented the increase of procollagen mRNA caused by H(2)O(2).

CONCLUSION

An oxidant stress caused by the infusion of peroxides in an organism with a weak antiperoxide capacity induces the transcription of the gene encoding for procollagen alpha1(I). The results confirm the antiperoxide activity of lung glutathione. Parenteral nutrition could be a clinical condition favoring the initiation of lung fibrosis, especially in premature newborn infants who have low glutathione levels.