4-Deoxypyridoxine inhibits chronic granuloma formation induced by potassium permanganate in vivo

MCP-1 and MIP-2 response in Trichinella spiralis infected mice treated with 4-deoxypyridoxine (4-DPD)

Chemokines are involved in a number of pathophysiological conditions, such as inflammatory processes and are divided in two major subfamilies, C-X-C and C-C chemokines. The C-C chemokines are monocyte chemotactic protein 1-2-3-4-5, while C-X-C chemokines include MIP-2, IL-8, etc. We studied the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue and serum in Trichinella spiralis infected mice treated and not treated with 4-deoxypyridoxine, a potent Vit. B6 antagonist which inhibits humoral and cellular immune response. MCP-1 and MIP-2 were measured in homogenized tissue and serum and determined by a specific ELISA. Here we found the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue of T. spiralis infected mice were significantly increased after 10 days and peaked on day 20 post-infection; however, the levels of MIP-2 in mice treated with 4-DPD was lower than that of untreated mice at day 20. MCP-1 also peaked at days 20 and 40. Animals treated with 4-DPD also inhibited the production of MCP-1, compared with untreated animals. The maximum inhibition was at day 40. These inhibitory effects on MIP-2 and MCP-1 were also repeated in the serum determinations, but were not significant. This study demonstrates that MIP-2 and MCP-1 are stimulated in serum and tissue of T. spiralis infected mice and 4-DPD-treated animals significantly inhibited them.

Vitamin B6-deficient diet plus 4-deoxypyridoxine (4-DPD) reduces the inflammatory response induced by T. spiralis in diaphragm, masseter and heart muscle tissue of mice

Animals fed diets deficient in vitamin B6 develop microcytic anemia, alterations of growth, and other pathologies. 4-deoxypirydoxine is a potent antagonist of vitamin B6 coenzyme which depresses IL-1, TNF and IL-6 and has anti-inflammatory properties. The aim of this study was to show the anti-inflammatory effects of 4-DPD on chronic inflammation caused by the nematode parasite T. spiralis, specifically on the recruitment and the activation of inflammatory cells. Two groups of mice, 6 weeks of age, were used: one was maintained on a vitamin B6-deficient synthetic pellet diet for 15 days before injection of the nematode, and administered an intraperitoneal injection (i.p.) of 4-DPD (250 microg/mouse) for 15 days (the first, 5 days before infection), and the second group was maintained on a normal diet for the total duration of the experiment. These two groups were then injected with 150 larvae (L1-T7 spiralis) per os. Chronic inflammation was caused by infection of treated or untreated mice with T7 spiralis parasite. After 14 days post-infection all mice developed a chronic inflammatory response. Mice fed with a B6-deficient diet showed a significant decrease in the number of cysts found in the diaphragm when compared to mice treated with normal diet. In addition, in all mice treated with vitamin B6-deficient diet plus 4-DPD the average body weight was significantly lower, compared to the mice on normal diet in all weeks examined. Moreover, in sections of the diaphragm, masseter and myocardium muscles, the infiltration of inflammatory cells, such as macrophages, lymphocytes, and eosinophils were more intense in untreated mice compared to those fed a vitamin B6-deficient diet. These results show that BALB/c mice infected with T. spiralis and fed a vitamin B6-deficient diet plus the vitamin B6 antagonist, 4-DPD, prolong the time of invasion of the larvae in the muscle cells, influence the recruitment of inflammatory cells and the intensity of the inflammatory reaction compared to infected untreated mice (control).

IgG, IgG1 and IgM response in Trichinella spiralis-infected mice treated with 4-deoxypirydoxine or fed a Vitamin B6-deficient diet

The aim of this study was to investigate the effect of pyridoxine (Vitamin B6) deficiency on the immunological response of BALB/c mice infected with the parasite T. spiralis. Specific anti-parasite IgM and IgG immunoglobulins were detected by ELISA method in the serum of treated animals at different periods for 60 days post infection. Vitamin B6-deficiency was induced in two separate groups of mice by either (1) maintaining the mice on a Vitamin B6-deficient synthetic pellet diet for 40 days before infection, or (2) by daily intraperitoneal injection of 8 x 10(5) M/100 microl of 4-Deoxypyridoxine (4-DPD), a potent antagonist of Vitamin B6 for 20 days prior to infection. These two groups of mice were then injected with 100 larvae (L1-T. spiralis) per os. Parasite burdens in the mice were observed by light microscopy. Cysts were present in the diaphragms of the mice after 60 days post-infection. Parasite specific IgG, as well as IgG1 levels were determined in the sera of infected mice fed a normal diet. These levels were found to be lower in the 4-DPD-treated mice compared to the untreated mice. The inhibition started from the 10th day and continued to the 60th day, and in the 4-DPD-treated group the inhibition initiated after 24 h to 60 days. IgM level also was depressed by 4-DPD, starting from 24 h after injection of the compound. In mice fed Vitamin B6-deficient diets the levels of IgG were lower than in mice fed normal diets. These results show that BALB/c mice infected with T. spiralis and fed either a Vitamin B6-deficient diet or a diet which included the Vitamin B6-antagonist, 4-DPD, both influence the course of IgG, IgG1 and IgM production.

Pyridoxine deficiency: new approaches in immunosuppression and chemotherapy

Pyridoxine deficiency leads to impairment of immune responses. It appears that the basic derangement is the decreased rate of production of one-carbon units necessary for the synthesis of nucleic acids. The key factor is a pyridoxine enzyme, serine hydroxymethyltransferase. This enzyme is very low in resting lymphocytes but increases significantly under the influence of antigenic or mitogenic stimuli, thus supplying the increased demand for nucleic acid synthesis during an immune response. Serine hydroxymethyltransferase activity is depressed by deoxypyridoxine, a potent antagonist of pyridoxal phosphate, and also by known immunosuppressive or antiproliferative agents. The combination of these agents is additive. Our results lead us to suggest the following medical applications: (a) combination of deoxypyridoxine with immunosuppressive or chemotherapeutic drugs may be effective in cases of immunosuppressive therapy or organ transplantation, (b) the development of special agents directed against the serine hydroxymethyltransferase apoprotein may prove to be a valuable medical tool, since this enzyme presents an excellent target for chemotherapy, (c) lymphocytes of individual patients could be used to design tailor-made specific immunosuppressive or chemotherapeutic treatment, and (d) the serine hydroxymethyltransferase activity of lymphocyte culture presents an excellent indicator for the evaluation of potency of immunosuppressive, chemotherapeutic or genotoxic compounds in a simple and rapid test.

Prevention of splenic granuloma formation in adjuvant arthritis by 2-acetyl-4-tetrahydroxybutylimidazole (THI)

Adjuvant-induced arthritis (AA) in Lewis rats is a widely used model of chronic inflammatory arthritis. Non-articular features such as weight loss and necrotizing granulomas of the spleen and lymph nodes also occur in this model. The compound 2-acetyl-4-tetrahydroxybutylimidazole (THI) marginally delayed the development of AA. However, this agent had no effect on the incidence or severity of disease. In contrast, THI totally prevented granuloma formation in the spleen and associated splenomegaly. We conclude that THI may be a useful adjunctive agent for some inflammatory diseases.

Generation of TNF alpha, IFN gamma, IL-6, IL-4 and IL-10 in mouse serum from trichinellosis: effect of the anti-inflammatory compound 4-deoxypyridoxine (4-DPD)

Infections caused by the nematode Trichinella spiralis is characterized in the host by an inflammatory response with cytokine production. In these studies we have detected TNF alpha, IL-6, IFN gamma, IL-4 and IL-10 in the serum of 10 mice infected with T. spiralis. Moreover, we detected, for the first time, these cytokines in the serum of mice treated with 4-DPD, a potent antagonist of vitamin B6 coenzyme which has anti-inflammatory properties. 4-DPD was used at 100, 400, 800 micrograms/bolus for 20 days, starting one day before the infection. After 15 days of T. spiralis infection, TNF alpha reached a maximum level, while IL-6 was maximal after 7 days, IFN gamma at 20 days and IL-4 at 14 days. IL-10 was not affected by the T. spiralis infection. When the animals were treated with 4-DPD at the reported dosages and infected with T. spiralis the inhibition of TNF alpha and IL-6, were dose-dependent in the first 7 days while IL-4 was reduced only at 400-800 micrograms/bolus. 4-DPD-treated mice did not statistically (P > 0.05) affect the generation of IFN gamma. In healthy animals the production of cytokines were not measurable, just as it was in non-infected animals treated with 4-DPD. The increase of cytokines such as, TNF alpha and IL-6 may be related to the severity of the disease, boosting the host's resistance to the pathogen and inhibiting parasite survival. In addition, the augmentation of IL-4 production enhances T and B cells and macrophage responses and may stimulate T-cell antibody-mediated response to the pathogen. 4-DPD, an inhibitor of IL-1 and inflammatory reactions, proved to be most effective on TNF alpha and IL-6, which are mainly produced by macrophages.