Histochemical and ultrastructural analysis of the action of naproxen on tail fin regeneration in carp (Cyprinus carpio)

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of rheumatoid arthritis and osteoarthritis, and are also indicated for periarticular and musculoskeletal diseases. However, the use of NSAIDs is limited by their toxicity. NSAIDs have a variable effect on the regeneration of cells and extracellular matrix that depends on the dose used. In this work, we examined the effect of naproxen, a NSAID, on tail fin regeneration in carp (Cyprinus carpio), a teleost fish that is a good model for studying the growth of connective tissue in vivo. We used histochemical, ultrastructural and morphometric analyses to assess the synthesis, deposition and organization of the lepidotrichial extracellular matrix components and the total area of regenerating fins, including lepidotrichia, epidermis and connective tissue. Naproxen (15.6 mg/L in the tank water) did not affect the formation of the epidermal cap and blastema, the differentiation of blastemal cells in scleroblasts or the synthesis, deposition, organization and mineralization of lepidotrichial matrix components. In addition, there was no significant difference in the area of regenerated tissue between control and naproxen-treated fishes. These results indicate that at the concentration tested, naproxen had no effect on tail fin regeneration.

Binding of naproxen to serum proteins in patients with liver cirrhosis and healthy individuals

A three-fold decrease of the in vitro ability of serum proteins to bind naproxen was shown in patients with cirrhosis of the liver compared to healthy individuals. This decrease was caused by quantitative changes in serum proteins in the sera of patients with liver damage. Lower doses of naproxen are therefore suggested in the treatment of patients with liver dysfunction