Recherche et évaluation des activités biologiques de trois extraits d’Helix aspersa (aqueux, hydro alcoolique et organique)

Abstract

Although the field of biotechnology has developed extraordinarily in recent years, therapies remain ineffective and can cause side effects in patients, which is why the laboratories have turned to the search for new natural products. Helix aspersa is a terrestrial mollusk that is widespread in Mediterranean countries and is part of the food habitude. It is an important source of protein and mineral salts and has several therapeutic effects known for centuries. One of the main prospects of our study is the evaluation of the anti-inflammatory, anti-tumor and anti-angiogenic effects. Three extracts were prepared using solvents with different polarity: an aqueous extract, an hydroalcoholic extract and an organic extract. Then, a model of acute pulmonary inflammation was developed to evaluate in vivo the anti-inflammatory activity of extracts by measuring total white blood cells and white blood cells in bronchoalveolar fluid, myeloperoxydase activity and analyzing the histology of pulmonary tissue. Analysis of the results showed that the extracts had anti-inflammatory activity by decreasing the total leukocyte count in blood and in bronchoalveolar fluid, protecting the pulmonary tissue by modulating neutrophil activity and decreasing protein concentration in bronchoalveolar fluid. The antiproliferative activity of the extracts was evaluated by trypan blue and the MTT test on several cell lines: MK2, A549, HUH7, K562, HUT-78 and SeAx. The chromatin condensation and nuclear fragmentation were evaluated by the Hoechst test in the HUT-78 and SeAx tumor cell line stimulated by the aqueous extract. The aqueous and hydroalcoholic extracts had antiproliferative activity against the HUT-78 and SeAx lines. The aqueous extract induced apoptosis in HUT-78 cells. The hydroalcoholic and organic extracts had an antiproliferative activity on the HUH7 line. The three extracts were not toxic on the MK2 normal cell line. The antiangiogenic effect was evaluated by measuring the expression of MMP-9 in the two HUT-78 and SeAx lines stimulated in the presence of the aqueous and hydroalcoholic extracts using was the zymography method. The aqueous and hydroalcoholic extracts had no effect on the production of MMP-9. At the end, we extracted the soluble proteins from meat lyophilized and we fractionated the extracts by anions exchange chromatography. The proteolytic activity using synthetic substrates and protease inhibitors as well as the antiproliferative activity of the different fractions obtained were measured. One of the fractions contains proteases and has antiproliferative activity against the K562 liquid line. Nevertheless, other contained no enzymes and had a toxic effect on the matrix tumor lines A549 and HUH7. It was concluded that the aqueous, hydroalcoholic and organic extracts of Helix aspersa had an anti-inflammatory and an anti-tumor effects, but did not have an antiangiogenic effect (on the expression of MMP-9)