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- Evaldsson, Chamilly, et al.
(author)
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4-Thiouridine induces dose-dependent reduction of oedema, leucocyte influx and tumour necrosis factor in lung inflammation
- 2009
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In: Clinical and Experimental Immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 155:2, s. 330-338
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Journal article (peer-reviewed)abstract
- Recent reports demonstrate a role for nucleotides as inflammatory modulators. Uridine, for example, reduces oedema formation and leucocyte infiltration in a Sephadex-induced lung inflammation model. Tumour necrosis factor (TNF) concentration was also reduced. Previous in vivo observations indicated that 4-thiouridine might have similar effects on leucocyte infiltration and TNF release. The aim of this study was thus to investigate the effects of 4-thiouridine in greater detail. We used a Sephadex-induced acute lung inflammation model in Sprague-Dawley rats. The dextran beads were instilled intratracheally into the lungs, which were excised and examined after 24 h. Sephadex alone led to massive oedema formation and infiltration of macrophages, neutrophils and eosinophils. Microgranulomas with giant cell formations were clearly visible around the partially degraded beads. A significant increase in bronchoalveolar lavage fluid (BALF) content of TNF and leukotrienes was also seen. 4-Thiouridine co-administration affected all variables investigated in this model, i.e. oedema, microscopic and macroscopic appearance of lung tissue, total leucocyte and differential leucocyte counts in BALF, TNF and leukotrienes C-4 (LTC4), LTD4 and LTE4 in BALF, indicating a reproducible anti-inflammatory effect. In conclusion, we have demonstrated that 4-thiouridine has anti-inflammatory effects similar to those of uridine. To our knowledge, this is the first demonstration of pharmacological 4-thiouridine effects in vivo. The results suggest nucleoside/nucleotide involvement in inflammatory processes, warranting further studies on nucleoside analogues as attractive new alternatives in the treatment of inflammatory diseases.
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| 2. |
- Evaldsson, Chamilly, 1978-
(author)
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Uridine, 4-thiouridine and isomaltitol in an asthma-like model : Anti-inflammatory and modulating effects
- 2009
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Doctoral thesis (other academic/artistic)abstract
- In chronic inflammatory diseases like asthma or rheumatoid arthritis, erroneous and exaggerated accumulation of leukocytes in a tissue inadvertently causes the body harm. Several efficient anti-inflammatory drugs exist, for example corticosteroids and cyclo-oxygenase inhibitors. However, these drugs have potent and diverse effects and often act by inhibiting events subsequent to initiation of the inflammatory response, leading to more or less severe side-effects, especially when used in high doses for long periods of time. For this reason, strategies aimed at early inhibition of recruitment and activation of leukocytes have been suggested as safer and more specific approaches to reduce inflammation.Leukocyte adhesion to activated endothelium is a prerequisite to the following activation and extravasation, and takes place in the initial phase of inflammation. By using a model that allows leukocytes to adhere to tumour necrosis factor (TNF)-activated endothelial cells, thus mimicking aspects of an inflammatory reaction, we found that uridine, 4-thiouridine and isomaltitol could all reduce adhesion. This suggested that they may have anti-inflammatory potential.We therefore tried the three substances in a Sephadex-induced lung inflammation model and found that uridine and 4-thiouridine have several anti-inflammatory effects, such as being able to reduce leukocyte accumulation, decrease TNF protein levels and partly inhibit the oedema induced by Sephadex. Isomaltitol turned out to have immunomodulating, rather than anti-inflammatory, effects, which could be of interest in diseases where inadequate inflammatory responses are a problem.
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