Amelioration of rat adjuvant arthritis by therapeutic treatment with bindarit, an inhibitor of MCP-1 and TNF-alpha production.

OBJECTIVE: This study was designed to evaluate therapeutic effects of bindarit, an indazolic derivative able to inhibit monocyte chemoattractant protein-1 (MCP-1) production, in adjuvant induced arthritis in rats. MATERIALS AND METHODS: Arthritis was induced by Freund's complete adjuvant injection. Bindarit was given as a 0.5% medicated diet starting on day 11 after adjuvant injection. The course of arthritis was monitored by sequential paw volume measurement and by radiologic and histologic evaluations. Human osteoblast cell line Saos-2 stimulated with Interleukin-1 (IL-1) was used to assess in vitro bindarit effect on MCP-1 release. In addition, in vivo effects of bindarit on cytokine production were studied in mice injected with lipopolysaccharide (LPS). Immune function studies were performed in mice by evaluating ex vivo antibody response to ovalbumin and splenocytes proliferation to Concanavalin A (Con A). RESULTS: In adjuvant-induced arthritis in rats, bindarit possessed therapeutic activity resulting in a significant inhibition of paw inflammation. Evidence for a disease-modifying activity was also indicated by amelioration of radiologic alterations and by histological evaluation of joints. Additional evidence for beneficial effects in osseous inflammation was provided by an in vitro assay in which bindarit inhibited the release of MCP-1 from IL-1 stimulated osteoblast cells. Moreover, in a murine model of LPS-induced cytokine production bindarit reduced MCP-1 and tumor necrosis factor (TNF)-alpha increase without affecting IL-1 and IL-6 levels. Finally, the drug, given as a 0.5% medicated diet for 14 days, did not affect either anti-ovalbumin serum antibody production or splenocytes proliferative response in mice. CONCLUSIONS: Results obtained indicate that bindarit beneficial effects in experimental arthritis are correlated to MCP-1 and TNF-alpha inhibition and suggest that the control of cytokines and chemokines production can have considerable relevance as regards strategies for the treatment of chronic inflammatory diseases.

Mechanism of the inhibitory effect of melatonin on tumor necrosis factor production in vivo and in vitro.

Melatonin is an antioxidant. Since other antioxidants inhibit the production of tumor necrosis factor (TNF) induced by lipopolysaccharide, we investigated its effect on TNF production in vivo and in vitro and on lethality associated with endotoxic shock. Administration of melatonin to mice (5 mg/kg, s.c., 30 min before or simultaneously with lipopolysaccharide) inhibited serum TNF levels by 50-80% and improved survival of mice treated with a lethal dose of lipopolysaccharide. By studying other, structurally related, indolamines (N-acetyl-5-hydroxytryptamine, 5-methoxytryptamine and 5-hydroxytryptamine) we found a good correlation between antioxidant activity (for which the 5-methoxy group is essential) and the inhibition of TNF production in vivo and in vitro in mononuclear cells. Melatonin did not increase serum corticosterone and did not modify the elevation of serum corticosterone levels by lipopolysaccharide or by interleukin-1. Furthermore, it exerted its inhibitory effect in adrenalectomized or hypophysectomized mice also, indicating that its effect is independent of the hypothalamus-pituitary-adrenal axis.

Bindarit prolongs survival and reduces renal damage in NZB/W lupus mice.

OBJECTIVE: The present study was designed to investigate the effects of bindarit on animal survival and renal damage in murine lupus autoimmune disease. METHODS: Female NZB/W mice were used. Bindarit was administered, as a 0.5% medicated diet, starting either before the onset of the pathology or early in the course of the disease, in order to assess the effects of age upon the response. Furthermore, the effects of combined administration of bindarit with low dose i.p. cyclophosphamide bolus were also studied. Proteinuria and anti-dsDNA antibody levels were determined during the course of the study. Renal damage was evaluated by light microscopy. RESULTS: Bindarit markedly prolonged the NZB/W mouse life span (p < 0.001 vs. controls), showing a significant difference even against high dose cyclophosphamide (90 mg/kg ip bolus) chosen as the reference (p < 0.01). Bindarit significantly reduced the degree of renal damage, delayed proteinuria and did not prevent autoantibody development, thus confirming the lack of immunosuppressive activity. CONCLUSION: The present results and other experimental data demonstrating the capacity of the drug to interfere with the inflammatory and immune response cross-talking, indicate that bindarit exerts its action in murine lupus through a novel and original mechanism. These findings, coupled with the evidence that the drug possesses a very safe toxicological profile, suggest that further investigations to assess the potential value of bindarit in the treatment of SLE are warranted.

Benzydamine protection in a mouse model of endotoxemia.

OBJECTIVE: Previous studies have shown that benzydamine (40 mg/kg s.c.) is able to inhibit tumor necrosis factor (TNF) production and to reduce mouse lethality when administered before or concomitantly with LPS. The present study was designed to further investigate benzydamine activity against LPS-induced toxicity in terms of potency and therapeutic effects. METHODS: Female Balb/c mice were used. A dose-response curve of animal lethality versus endotoxin dose was performed (LD50 = 45 micrograms/mouse). Therapeutic effects were studied selecting the dose of LPS to achieve an LD100 (160 micrograms/mouse). Mortality was assessed daily and mice were followed for 8 days. The potential mode of action of therapeutically administered benzydamine was also investigated. TNF alpha and IL-1 beta levels were measured, at 5 h after LPS injection, both in sera and in lungs. Moreover, the drug was assayed in a TNF-dependent cytoxicity test. RESULTS: Benzydamine, administered at 20 mg/kg s.c. simultaneously with the endotoxin, significantly increased LPS LD50 up to 230 micrograms/mouse (p < 0.05). Moreover, the drug significantly protected mice against LPS-induced lethality when administered either 30 min or 4 h after endotoxin injection (p < 0.001). Benzydamine, therapeutically administered at 20 mg/kg s.c., significantly reduced TNF alpha and IL-1 beta production induced by LPS both in serum and lungs and it was shown to inhibit TNF-dependent cytoxicity on L929 cells. CONCLUSIONS: These results clearly demonstrate the therapeutic activity of benzydamine in a simple model of endotoxic shock. Available data confirm the potential role of benzydamine as an anti-cytokine agent and provide suggestions for novel therapeutic applications of this anti-inflammatory drug.