4-Deoxypyridoxine inhibits chronic granuloma formation induced by potassium permanganatein vivo

4-Deoxypyridoxine (4-DPD) is a potent antagonist of Vitamin B6 coenzyme which inhibits IL-1, lymphocyte proliferation and has demonstrated that tollerance to skin grafts can be induced by administering splenic cells to pyridoxine-deficient mice. Chronic inflammation induced by dorsal injections of 200 l of a 140 saturated crystal solution of potassium permanganate (KMnO₄) in mice treated or untreated with 4-DPD (400 g/dose), has been investigated. After 7 days all mice developed a subcutaneous granulomatous tissue indicative of a chronic inflammatory response, at the site of injection. KMnO₄-treated mice injected intraperitoneally with 4-DPD (400 g/dose) on 5 consecutive days (the first at the same time of induction of the granuloma) show a significant decrease in size and weight of granuloma when compared to mice not treated with 4-DPD (Controls). In addition, in all mice treated with 4-DPD there was a strong inhibition of TNF in serum (P<0.01) and in supernatant fluids (P<0.05) from minced granuloma, while IL-6 was inhibited in the supernatant fluids (P<0.05) of minced granulomas but was not detected in the serum of treated and untreated mice. In this study we show for the first time the antiinflammatory effect of 4-DPD on chronic inflammation and the inhibitory effect of TNF and IL-6 generation in supernatant fluids from minced granulomas.