Diagnostic and Treatment of Chelicobacteriosis of Stomach
Development of New Methods of the Treatment and Diagnosis Diseases Caused by the Bacterium Helicobacter Pylori
Tech Area / Field
- MED-DID/Diagnostics & Devices/Medicine
- MED-DRG/Drug Discovery/Medicine
3 Approved without Funding
National Academy of Sciences of the Republic of Belarus / Institute of Biophysics and Cell Engineering, Belarus, Minsk
- Belarusian State Medical University, Belarus, Minsk
Project summaryThe main purpose of the present project is the development of a principally new effective method of treatment and prophylaxis of gastric diseases caused by the pathogenic microorganism Helicobacter pylori (H. pylori) and also creation of a noninvasive express test-method of laboratory diagnosis of Н. pylori infection.
The urgency of the given research is conditioned by extraordinary abundance of Н. pylori infection, that is a pathogenic microorganism of the majority of gastric diseases of the population all over the world, and absence of effective methods of treatment and diagnosis of Н. pylori infection.
It is widely accepted that gastric diseases are the most widespread pathology of man. No less than 50% of world population is affected by chronic gastritis discounting its consequences Parsonnet J.(1995) Aliment. Pharmacol. Ther. 9. Suppl.2, 45.
Since 1995 it has been proved that the bacterium Helicobacter pylori (H. pylori) is the main cause of chronic gastritis and the majority of other gastric diseases. According to the latest evidence the mentioned bacterium is found at 95% duodenum ulceration and at 70-80% cases of stomach peptic ulcer [Marachovsky K.J. (1998) Medicine 23, 38].
More recent studies have shown an association between long-term infection with H. pylori and the development of gastric cancer. Gastric cancer is the second most common cancer worldwide [Forman D., et al. (1994) Lancet 343, 243].
There is an opinion that the H. pylori infection is the most widespread infections human disease Achtman M., Suerbaum S. (eds). Helicobacter pylori: Molecular and Cellular Biology (Horizon Scientific, Norfolk, 2001). Such mass infection of the population by the Н. pylori bacteria and accordingly high abundance of gastric diseases, caused by it undoubtedly testifies to insufficient efficiency of present methods of treatment of the Н. pylori infection. In connection with this the development of new effective method of treatment of the gastric Н. pylori infection is an extremely significant and indispensable problem.
According to the adopted viewpoint, the possibility of the survival and viability of this bacterium in acidic environment of a stomach (1% of a hydrochloric acid) is due to two the most important features. H. pylori contains urease enzyme, which is absent both in man and animals Eaton K.A., et al. (1991)Infect. Immun. 59, 2470. Another characteristic property of H. pylori bacillus is extraordinary high mobility Josenhans C., Suerbaum S. in Helicobacter pylori: Molecular and Cellular Biology (eds Achtman M., Suerbaum S.) P. 171-184 (Horizon Scientific, Norfolk, 2001). Above-mentioned properties are considered usually as dominating virulence factors in the development on H. pylori infection.
Urease plays a determining role in colonization by bacteria of a stomach mucous of the man. It is considered that bacillus splitting a urea frees an ammonia which neutralizes an acid and thus promotes the initial colonization and survival [Mobley H.L.T., et al. (1995) Microbiol. Rev. 59, 451].
In this connection participants of the project propose new methods of H. pylori diagnosis and treatment. Our preliminary but positive results give every reason to hope that a simple and express test-method may be developed for H. pylori associated diseases diagnosis. This method is utterly not traumatic therefore it is especially suitable for the daily examination of inpidual patients and for the inspection of considerable population groups.
The elaborated method is founded on employment of urease inhibitors as chemotherapeutic agents. Preliminary selection and testing of such compounds already has been carried out at the Institute of Photobiology of Belarus National Academy of Sciences. Essentially the offered method of the cure is directed to realization of the stomach natural defending possibility, a high acidity of milieu, which is neutralized in consequence of H. pylori urease enzymatic activity. We consider high acidity of the gastric milieu to be rather a basic protective mechanism than a pathogenic factor.
Antibiotics and some other anti-microbial compounds are generally accepted means of H. pylori eradication. In comparison with them, urease inhibitors have obvious advantage due to the strict by specific character of the action and thus are unable to damage the intestine microflora and to disturb their natural composition.
Our preliminary researches show that we could select some principally new anti-Helicobacter substances in addition to urease inhibitors. The mobility of pathogenic organism’s cells plays the essential role in the development of Н. pylori – infection. It was found that as against the wild strains, not mobile mutants of Н. pylori are not capable to survive long time in a stomach. Rather perspective is the selection and bacteriological tests of the agents capable to lock up the mobility of Н. pylori cells effectively. Such agents will be taken from among natural metabolites and foodstuff.
From a number of the widely used food additions we select the product, which is capable to sour fast and intensively the intracellular contents of microorganisms in acidic environment. Its preliminary tests have shown that it causes fast and full destruction of cells of acidophilus microorganism in acidic values of рН. As substances with the potential eradication possibility we select substances of not antibiotic nature, actively at acidic values of pH, corresponding to the substances from group of natural metabolites in a human body. Moreover, a series from selected substances have passed standardized toxicological study at an international level, as it is used as additive components in food production.
Perspectives of a clinical employment of urease inhibitors may be broader than the exceptionally gastric diseases. The problems, caused by urease-producing bacteria are not limited to the pathogenesis of gastric and duodenal ulceration – the damaging effects on urease have been shown to contribute to the pathogenesis of urinary calculus formation, pyelonephritis, and cardio-vasculas diseases. Urease activity is also involved in the pathogenesis of hepatic encephalopathy. The mechanism of this may be connected with the toxic effect of ammonia. Excess ammonia produced by urease activity of some bacteria is inadequately dealt with deteriorating liver function and may eventually lead to hepatic coma.
On the basis of express diagnostic method we propose to carry out preliminary but extensive screening of illnesses that presumably is associated with H. pylori infection.
Influence of the proposed project on progress in the field of development.
The creation of a not traumatic express test-method of laboratory diagnosis of Н. pylori infection will allow not only to control a process of the treatment of inpidual patients systematically, but also to make mass tests of the population and thus to appraise real epidemiological situation in regions.
The introduction of a principally new effective method of eradication of Н. pylori is capable to improve considerably the situation in unsuccessful now areas of medicine – in gastroenterology.
Development of new methods of diagnosis and the treatments of the Н. pylori infection has no analogy in world experimental and clinical medicine. Their introduction in clinical practice will undoubtedly promote the health improvement of the population - the treatment of one of the most mass infectious diseases of the man.
The participants of the project.
The group of the project participants consists of 9 main executors, among which there are 4 doctors of sciences (2 academicians of NASB) and 3 candidates of sciences. The group consists of 2 teams representing Institute of Photobiology of NASB and Byelorussian State Medical University. IPB NASB has a wide experience of researches in the field of a membrane biophysics, enzymology and microbiology. The analysis of Н. pylori associated gastroduodenal diseases is carried out in clinics of BSMU during a number of years. The laboratory tests of diagnosis and then chemotherapeutic methods of treatment of Н. pylori infection will be carried out in IPB NASB. Also the selection of pharmaceuticals and definition of their effective concentrations with the use of a vegetative urease and cells of Н. pylori will be carried out. Methods of diagnostic and the treatments of Н. pylori infection will pass the final tests and further introduction in medical practice in clinic of BSMU. The execution of project envisages continuity and tight cooperation between IPB NASB and BSMU.
Expected results and their applying.
The solution of 4 primary goals will allow obtaining the following results:
– The development of reliable and effective noninvasive urease method of diagnosis of Н. pylori infection.
– Creation of a principally new method of treatment the of stomach chelicobacteriosis.
– The development of a not traumatic express test-method of laboratory diagnosis of H. pylori infection.
– Investigation of the role of Н. pylori - stomach infection as a pathogenic factor in case of diseases of other vital organs.
Proposed noninvasive express method of diagnosis of the Н. pylori infection is especially suitable for mass inspections of the population and also for the constant control of dynamics of disease for the inpidual patients. The development of the principally new methods of eradication of Н. pylori and consequently the treatment and prophylaxis of gastroduodenal diseases that are the most widespread human pathology, and will promote essential health improvement of the population of many and first of all developed countries. The indicated methods of treatment and diagnosis are simple and safe and so can be widely used not only in clinical but also in ambulant medical practice.
The participants of the project intend a protection of created intellectual property and first of all the protection of diagnostic and medical preparations that will matter for organization of their commercial production.
Peculiarity of the present project is the orientation to use of simple and cheap products of mass production as medical means that will be used as additive components and do not require toxicological tests.
Implementation of the purposes and problems of ISTC.
The execution of the project corresponds to the purposes and problems of ISTC:
– affords to scientists and specialists of Republic of Belarus involved in weapons designing a possibility for reorientation of their activity in the peace purposes;
– promotes integration of scientists of the Republic of Belarus in international community;
– supports fundamental and applied research in the peace purposes in the field of experimental and practical medicine;
– contributes to the solution of national and international problems of diagnosis and treatment of mass gastric diseases;
– supports transition to market economy and create conditions for self-financing of scientists involved in weapons designing in the future.
Volume of activity.
Duration of the project – 33 months. The participants of the project – Institute of Photobiology of NASB (IPB NASB) and the Byelorussian State Medical University (BSMU).
In the process of an execution of the project it is supposed to solve the following problems:
1. Modification of the urease method of diagnosis of the chelicobacteriosis of a stomach.
2. Development and implementation of the principally new methods of eradication of the H.pylori infection.
3. Creation of Noninvasive express test of diagnosis of H.pylori infection.
4. Detection of damages of other organs and systems of and organism associated with chelicobacteriosis of a stomach; searching of methods of their radical therapy.
Role of foreign collaborator.
According to the volume of activity within the framework of the tendered project the following forms of cooperation with foreign collaborator are matched:
– regular information exchange during implementation of the project;
– submission of the comments to the scheduled reports routed the participants of the project in ISTC;
– crossevaluation of results obtained during implementation of the project;
– testing and estimation of the methods of diagnosis and treatment of Н. pylori infection, elaborated during execution of the project;
– consulting on protection of intellectual property;
– joint patenting the methods of diagnosis and treatment of Н. pylori infection;
– rendering promotion to the participants of the project in visiting of international conferences; realization of joint working conferences and seminars.
The technical approach and methodology.
The basic researches in the field of a biophysics of diaphragms, enzymology and microbiology (IPB NASB), clinical experience of diagnosis and treatment of chelicobacteriosis of a stomach and its complications (BSMU) and also analysis of the literary served as the theoretical and methodological fundamentals of the present project. Qualification of the participants of the project, engaging the knowledge of medical biophysics and the microbiology have allowed to offer and to justify the principally new concepts of diagnosis and treatment of gastric diseases caused by the bacteria Н. pylori for the first time in medical practice.
The conditions of realization the urease reaction will be updated and the adequate pH-indicator will be selected for sensitization and accuracy of the urease method of diagnostis of Н. pylori. In the process of solution of the problem of eradication of Н. pylori infection the principally new method will be realized – the mobilization of natural protect mechanisms of a stomach, first of all high acidity. Proposed chemotherapeutic agents belong to the class of physiological metabolites and additive components and are not antibiotics. Their action is directed to suppression of adaption systems (factors of virulence) of Н. pylori bacteria – a high urease activity and mobility.
Problem 1. The reliability and sensitivity of invasive urease method of diagnosis of Н. pylori infection will be raised by selection of dye – рH-indicator possessing advantages in comparison with traditionally used phenolphtalein in the following parameters: proximity of a рH-optimum of catalytic activity of a urease and zone of рH-dependent transition of coloring, contrast рH-dependent change of colour. The researches will be executed with use of a vegetative urease and slurries of Н. pylori cells.
Problem 2. On the initial stage the potential inhibitors of urease from among pharmaceuticals, metabolites and additive components will be tested according to their capacity to block up catalytic activity of an enzyme. The definition of the mechanism of inhibition (competitive, noncompetitive etc.), kinetic parameters of the interaction of inhibitors with urease will be executed by a spectrophotometric method with the use of a vegetative enzyme.
From the group of inhibitors of a urease and protonofors of an alimentary genesis free fat acids will be selected those, which are most effective as the antibacterial agents in real conditions of the Н. pylori inhabitation - in acidic gastric environment.
Problem 3. As the living cells of a pathogenic organism are determined by the bacteriological method in evacuation of infected by chelicobacteriosis of stomach patients, the noninvasive express test for diagnosis of Н. pylori infection according to its urease activity will be developed. In order to prevent false – positive results the urease reaction will be conducted in acidic environment (рН 3.0), i.e. in conditions when only the enzyme of Н. рylori bacteria saves its activity.
Problem 4. The persistently developing diseases of the vital organs (ischemic illness of heart, encephalopathy etc.) are often associated with urease positive bacterial infections, including Н. pylori. The most probable pathogenic factor of the indicated complications is the urease activity of bacterial cells causing the increase of concentration of ammonia in liquid environments of an organism. In this connection the extensive examination of the patients with somatopathies will be conducted with the purpose of detection of Н. pylori infection and definition of a level of ammonia in their blood. In cases of urease – associated hyperammoniemia an eradication of an exciter will be used. Investigation of methods of radical therapy of hyperammoniemia and its complications with the use of physiological metabolites of an organism also will be attempted.