Etude de l’effet inhibiteur des substances chimiques (magnésium et citrate) et naturelles (Origan et Gingembre sur la cristallisation oxalo-phosphocalcique in vitro

Abstract

Urolithiasis is a common and multifactorial complex that requires an understanding of the mechanisms involved in the pathology lithogenesis. Supersaturation of urinary medium is the initial stage of lithogenic process that generates primitive phase consisting of insoluble crystals and ensures growth. Indeed, when supersaturation is sufficient, it leads to nucleation and crystal growth in which, following aggregation, may cause stones formation. However, a better understanding of the stages of crystallization, is a good definition of therapeutic ways to reduce the formation of crystals in the urine, allow effective prevention to avoid the risk of recurrence in which the practitioner and patient face. Among the preventive therapeutic measures, we find the use of crystallization inhibitors. From this point of view we tested some chemicals (magnesium citrate) and natural (Origano, Ginger) on calcium oxalate (whewellite) and calcium phosphate (struvite) crystallization to eliminate, reduce or slow down the phenomenon of crystallization, kinetics was followed with time at 37 °C and under constant stirring. The analysis is done by polarized light microscope is confirmed by FTIR. The obtained results indicate that the effect of chemical inhibitors such as Mg and the citrate acts strongly on the germination phase of whewellite with an inhibition ratio exceeds 83 % and that for this the number and size, for struvite concentration of 7 mmol/l Mg was completely delay the onset of crystal 30 minutes crystallization concentration 2.5 mmol/l citrate had inhibitory effects on the number with 87% and 60% size. For natural inhibitors and their actions on the oregano extract whewellite decoction inhibitor seems to be the best at very high concentrations (75 %, 100 %) with a rate of 100 % at the beginning of the crystallization, ginger against has less effect on the number and size of crystals whewellite and this for all concentrations and extractions used modes. Finally for the inhibitory action of oregano and ginger on the phosphate crystallization (struvite) was found which was highly very effective in elimination of the crystals formed. In conclusion, the natural or chemical inhibitors tested had a significant inhibitory potency on artificial urine calcium oxalate and phosphate type, which gives signs of being profitable future in the prevention of urolithiasis.