Avaliação gastrotóxica e toxicológica pré-clínica da alga Lithothamnion calcareum

Abstract

Lithothamnion calcareum is a red alga that belongs to the family of coralinaceas. This family has as their main feature the precipitation of calcium carbonate and magnesium in their cell walls in the form of calcite crystals. Besides these two main compounds, the calcareous algae are composed of more than 20 oligoelements. L. calcareum is marketed in Brazil and abroad as a nutritional calcium and other minerals supplement under the brand name Vitalidade + 50 ® by the company Phoster Algamar. Because of the potential use of algae in the therapy of inflammation gastrotoxicity studies, were performed using the commercial product based on L. calcareum in doses of 30, 120 and 480 mg/kg, since the major side effects of the current anti-inflammatory drugs are gastrointestinal disorders. In addition, studies aimed to evaluate the pre-clinical toxicity of this product were also performed, since they are required from the regulatory agencies around the world. The acute toxicity test was performed at the dose of 2000 mg/kg, with no clinical sign of toxicity. The subchronic toxicity test (90 days) was performed at the doses of 1000 and 2000 mg/kg. A study with a satellite group was also carried out to evaluate whether it would occur reversibility of the potential toxic effect. Although it did not exercise a role in gastroprotection in rats, did not cause either an increase in gastric irritation, which occurs with the use of non-steroidal anti-inflammatory drugs. Our studies have also shown that L. calcareum can cause changes on biochemical patterns in the subchronic toxicity test. Serum levels of albumin, total proteins and calcium were decreased, whereas serum levels of creatinine increased, suggesting kidney damage associated or not with liver damage, with no reversibility observed for most of these parameters. However, most of the biochemical changes mentioned above occurred at the dose of 2000 mg/kg, which is very high when compared to those (10 to 100 mg/kg) under study for anti-inflammatory action, indicating the safety of the product in the therapeutical doses. We believe that further studies should be done (chronic test) in order to verify the occurrence of renal failure and/or liver disease and to elucidate possible mechanisms of pre-clinical toxicity.