A crystallographer of St Petersburg University, Alina Izatulina, became the winner of the initiative research competition for young scientists of the Russian Science Foundation. In the next two years, she will study how the formation of kidney stones is affected by bacterial infections, and whether it is possible to stop the development of urolithiasis with antimicrobial agents.
«I plan to continue research related to the study of the effect of various pathogenic processes on the formation of kidney stones,» said Alina Izatulina. «With the help of model experiments, we have already managed to prove that, for example, in the presence of the Pseudomonas aeruginosa the crystallisation of calcium oxalate begins twice as fast. We conducted targeted experiments with staphylococcus, E. coli, rotavirus and the Coxsackie virus. On model systems, the presence of bacteria leads to the production of new crystalline phases, for example, apatite and struvite. Now I want to understand how these processes will be affected by antibacterial drugs.»
The second area of the research is related to the study of the zonality of stones, that is, a description of the «life history» of the human kidney aggregate. If you cut a stone, you can see that it has rings that look like tree rings. They can help answer important questions for urologists. What affects the speed of stone formation? How can you slow it down? And how to make the stone have a «smooth» structure, which is less likely to damage the urinary tract when removing the stone?
Previously, scientists of St Petersburg University during model experiments succeeded in demonstrating that the amino acids present in the urine affect the crystallisation in the human urinary system. For example, glycine, aspartic and glutamic amino acids, adsorbed on the surface of the growing stone, prevent stone formation; and the popular taste enhancer sodium glutamate, on the contrary, stimulates the formation of sediment in a fluid that mimics human urine. True, the researcher notes, simply increasing the amino acids in the diet does not solve the problem — the kidneys have more complex chemical processes. To conduct similar experiments Alina Izatulina and her colleagues are assisted by a large collection of kidney stones, which includes about 2000 specimens with data on patients. By the way, the length of the largest stone is 13 centimetres — it was removed during a surgical operation.
«Kidney stones in terms of mineral composition are basically of three kinds: phosphate, oxalate and urate,» Alina Izatulina stated. «In my candidate’s dissertation I paid most attention to oxalate stones, because they make up about 70% of all cases of urolithiasis in St Petersburg and the Leningrad region, now I plan to include all kinds of urinary stones. The wide prevalence of oxalate stones is associated with food: oxalates are salts of oxalic acid, which is found in many vegetables, in particular in tomatoes and sorrel. However, the disease does not arise because of the characteristics of the diet, its main cause is a metabolic disorder».
The study was supported by the grant of the RNF No. 18-77-00026.
In the risk group, as the researcher notes, there are people who lead a sedentary lifestyle, in which various inflammatory processes are observed. Similar problems are faced by pregnant women, as well as those who drastically change their place of residence and start eating other food and water. The study of crystallographers of St Petersburg University will help to better understand the mechanisms of formation of kidney stones, and hence — to find effective ways of treating this disease.