WO2008135642A1

WO2008135642A1 - Method for determining a score representing the oxidative stress of a patient, on a scale of 0 to 10

Info

Publication number: WO2008135642A1
Application number: PCT/FR2007/051215
Authority: WO
Inventors: Michel Brack; Olivier Brack; Gérard Dreyfus; John Chapman; Anatol Kontush; Dominique Bonnefont-Rousselot
Original assignee: Swiss Line Services Ltd
Priority date: 2007-05-04
Filing date: 2007-05-04
Publication date: 2008-11-13
Also published as: CN101842791A

Abstract

Method for determining a score representing the oxidative stress of a patient, characterized by the succession of the following steps: - in an initial calibration step: - a series of biomarkers is chosen and these biomarkers are evaluated by assaying a panel of people in order to obtain a database, and - a statistical analysis of this database is carried out so as to: - establish a severity scale for each of the biomarkers, - assemble the biomarkers into a set of groups of biomarkers, and - attribute a weight, on the one hand, to each group of biomarkers and, on the other hand, to each of the biomarkers within each group, then - several biomarkers of the patient are evaluated, - a rating on the severity scale is attributed to each of the values thus obtained, and - a score of the oxidative stress specific to the patient, Spatient, is calculated using the formula.

Description

"Method for determining a representative score of the oxidative stress of a patient, on a scale of 0 to 10"

The present invention relates to a method for determining a score representative of the oxidative stress of a patient on a scale of 0 to 10.

It is known that oxygen is the fuel of cells, and there are many publications in the literature on this subject.

However, some forms of oxygen, including free radicals, can be highly toxic to the body and cells as they catalyze oxidation reactions that may randomly alter biological molecules.

This is the phenomenon known to specialists as oxidative stress.

This phenomenon is involved in a wide range of diseases, in particular hepatitis, cancer, AIDS, Alzheimer's disease, Parkinson's disease ... and is also the essential motor of aging.

However, the medical profession today has the means to intervene on oxidative stress such as, for example, an improvement in lifestyle, nutritional care (following the recommendations of the National Program Nutrition Santé) or the administration of natural or synthetic antioxidants.

It would therefore be desirable to be able to evaluate the oxidative stress in each particular case in order to predict a risk of developing a pathology and to take early, as soon as an anomaly is detected, all the possible measures to remedy it.

However, the evaluation of oxidative stress in human medicine does not correspond to a problem solved today, even though different laboratories propose to explore this stress from essentially blood-based assessments based on the assay of certain biological markers.

However, these are more empirical approaches than truly scientific evaluation methods, especially since the markers used vary widely from one laboratory to another. Consequently, these assessments are not likely to allow the treatment of oxidative stress in current medicine and their particularly complex interpretation is the prerogative of a few specialists who have been exposed to oxidative stress for several years. The present invention aims to fill this gap by providing the medical profession with a scientific tool for obtaining from blood tests and biological assays an assessment of the oxidative stress of a patient materialized by a representative score of this stress, on a scale from 0 to 10 (from the least disturbed balance sheet to the most disturbed balance sheet).

Such a score is therefore indicative of a normal or more or less abnormal balance.

In the presence of an abnormal assessment, the doctor must then perform an interpretation work to assess the origin of this anomaly and prescribe to the patient the necessary measures to remedy it.

The relevance of these measures (advice on the hygiene of life, modification of the diet, in particular by increasing the intake of fruits and vegetables or antioxidant supplementation) can be controlled after a few months thanks to a new determination of the representative score oxidative stress.

In this context, the subject of the invention is thus a method for determining a score representative of the oxidative stress of a patient on a scale of 0 to 10, characterized by the following succession of steps: in a calibration step initial:

a series of biological markers related to oxidative stress are chosen and these biological markers are evaluated by assay, in particular from blood samples, in a panel of healthy persons or possibly with different types of pathologies and clinical disorders known in order to obtain a database, and

a statistical analysis of this database is carried out on the basis of relationships known in the medical field and described in the literature so as to:

- to establish for each biomarker a scale of severity associated with the observed deviations from reference values, - to gather the biological markers into a set of groups of biological markers respectively expressing different information that can be associated at different stages development of oxidative stress, and assigning a weight on the one hand to each group of biological markers, and on the other hand to each of the biological markers within each group, then

several biomarkers of the patient belonging to several groups of biological markers are evaluated,

- each of the values thus obtained is assigned a score on the gravity scale, and

a patient-specific Spatient oxidative stress score is calculated using the formula

where Max _m arker represents the maximum score of the biological marker in the gravity scale.

The process according to the invention was originally conceived, thanks to a multidisciplinary, medical and mathematical work, having lasted for a period of about four years.

Approximately 600 "first" blood tests for oxidative stress were performed on healthy patients or with different types of pathologies and clinical disorders, each time using a dosage of ten to twenty biological markers. In a second step, about 120 checkups were performed on patients who had been treated following an initial assessment that turned out to be abnormal.

This work made it possible to obtain a very complete database which appears in appendix 1 as an example. The abbreviations of the different biological markers, their units and the standards are given in Annex 2.

This database has been supplemented by information relating to the descriptive characteristics of the population monitored: sex, age, housing, professional activity ... and the medical history of patients: health status, personal medical history, and surgical, antecedents of direct siblings, progressive disease, treatments, level of stress ....

This database was examined by a medical team to identify and eliminate any outliers and then statistical analysis by a modeling technique so as to weight the values of the different biological markers according to parameters such as the age of the patient and to validate it based on the verification of known relationships and mentioned in medical literature.

Thus, correlations were found between the different biological markers on the one hand and between certain abnormalities of these biological markers and certain elements of the patient's personal and medical file on the other hand. It appeared that all of the biological markers assayed did not make it possible to recognize this or that disease, but that their abnormalities provided perfect information on the overall state of health of the patients.

Thus, two groups remarkable for their extreme phenotypes (perfect health and very poor health) have been individualized and studied for their absence or high level of oxidative stress.

The study of the information obtained led:

to associate with each biological marker a scale of gravity according to the results obtained on the whole of the balance sheets, to bring together the biological markers tested in groups of biological markers expressing different information, some expressing more the state of health of the patients and others are more related to a high risk of developing a particular pathology, and

to evaluate a weighting grid of the different groups of biological markers and of the different biological markers within each group.

Finally, a scale was developed that allows mathematical algorithms that take into account all of the above elements to calculate for each patient a score of 0 to 10 representative of their own level of oxidative stress.

This scale allowed to find on the whole of the database the patients in perfect health and those presenting a bad state of health.

It should be noted that, from a purely statistical point of view, this work made use of the following techniques and methods:

Descriptive statistics: Graphical and numerical adequacy tests with statistical laws - Determination of mean level and dispersion estimators, Graphical and numerical tests for the detection of outliers, Analysis of deviations by study of paired differences and associated tests (parametric and non-parametric),

Correlation Analysis and Modeling in Simple Linear Regression, Principal Component Analysis,

PLS (Partial Least Squares & Discriminant Analysis) regression modeling with cross-validation according to the so-called "split" blocks principle.

Evaluation of the scale is currently feasible interactively thanks to a utility developed under Microsoft ^® Excel in its 2003 version (Professional) in the form of a macro-command accepting the incomplete balance sheets due to a weighting adjusted in according to the dosages available.

To validate the scale thus conceived, a random file of 30 patients was assigned to three independent observers A, B and C experts in the field of oxidative stress.

They were asked to record the balance of each of these patients from 0 to 10 according to the severity of the oxidative stress that they imagined spontaneously, without having access to the personal and medical file.

Appendix 3 reproduces the diagnoses of each of the experts, their consensus, that is to say the average of the scores given by these experts, the Spatient score obtained following the implementation of the process according to the invention. as well as the gap between this consensus and this score.

These results show that the three experts made evaluations that were globally equivalent and superimposable on the quotation obtained by the process according to the invention. According to another characteristic of the invention, the biological markers are brought together in at least three groups of biological markers of increasing importance corresponding respectively to exogenous antioxidants, that is to say supplied from outside, to endogenous antioxidants. that is, cell synthesis and markers of oxidative damage.

The first two groups of biomarkers provide information on the state of health of the patients while the third group informs about the risks they have to develop certain pathologies. According to the invention, one can advantageously attribute to the first group of biological markers corresponding to exogenous antioxidants a weight equal to 1, the second group of biological markers corresponding to endogenous antioxidants a weight equal to 5 and the third group of corresponding biomarkers to markers of biological damage a weight equal to 10.

The first group of biological markers preferably contains at least seven biological markers consisting of vitamin C, vitamin E, copper, zinc, selenium, and vitamin C / vitamin E and copper / zinc ratios.

This first group may of course also contain other markers, among which, for example, alpha tocopherol (or vitamin E), gamma tocopherol, cholesterol, vitamin E / cholesterol ratio or beta carotene may be mentioned. . The second group of biological markers preferably contains at least four biological markers consisting of total glutathione GSH, oxidized glutathione GSSG, thiol proteins and the ratio GSH / GSSG.

This second group may also contain other biological markers such as, for example, glutathione peroxidase or even uric acid.

Finally, the third group of biological markers contains at least one biological marker chosen from oxidized low-density lipids (LDL Oxyd.) And the 8-hydroxy-guanosine / creatinine ratio, or oxidized DNA / creatinine.

This third group may also contain other biological markers such as, for example, lipid peroxides and antibodies against LDL Oxyd. or oxidized DNA.

It should be noted that in the context of the invention, overall satisfactory results have been obtained by attributing in each group the same weight, in particular equal to 1, to each of the aforementioned main biological markers.

It should also be noted that the score of a biological marker on the scale of gravity can according to the markers vary between 0 to 2 and from 0 to 10.

The method according to the invention therefore makes it possible to provide the physician with a score of between 0 and 10 giving an indication of the oxidative stress state of a patient, (moderate or significant oxidative stress).

This can, depending on whether this score should be considered normal or not, determine whether the patient is in good or bad health.

In the case of abnormal oxidative stress (moderate or important) the method allows to perform a qualitative interpretation of the score obtained by looking what is in this score the relative weight of different groups of biomarkers. This interpretation allows the physician to determine whether the abnormal oxidative stress that was revealed by the patient's score is essentially related, in order of importance:

- a relative deficiency in exogenous antioxidants: vitamin C and / or vitamin E and / or copper and / or zinc and / or selenium ..., - a relative deficiency in endogenous antioxidants: glutathione, thiol proteins ...,

- or the objectification of oxidative damage already present: LDL Oxyd., oxidized DNA ...,

From this observation, the doctor can decide to supplement this assessment by auxiliary dosages, to check the food intake in fruits and vegetables and / or to prescribe to the patient a treatment of the proven deficiencies thanks in particular to the administration of antioxidant compounds.

This prescription will of course be accompanied by a check of the balance sheet after a few months, after appropriate care.

ANNEX 2

Claims

R E V E N D I C A T IO N S

1 °) Method for determining a score representative of the oxidative stress of a patient, on a scale of 0 to 10, characterized by the succession of the following steps:

in an initial calibration step:

- to establish for each biological marker a gravity scale associated with the deviations from reference values,

to bring together the biological markers in at least three groups of biological markers respectively expressing different information that can be associated with different stages of development of the oxidative stress and respectively corresponding to exogenous antioxidants, endogenous antioxidants and biomarker markers. oxidative damage, and - assigning a weight to each group of biomarkers, and to each of the biological markers within each group, and

- several biological markers of the patient belonging to several groups of biological markers are evaluated, - each of the values thus obtained is assigned a score on the scale of gravity, and

2) Method according to claim 1, characterized in that the first group of biological markers corresponding to exogenous antioxidants is assigned a weight equal to 1, the second group of biological markers corresponding to endogenous antioxidants a weight of 5, and the third group of biological markers corresponding to markers of biological damage a weight equal to 10.

3. Process according to claim 1, wherein the first group of biological markers contains at least seven biological markers consisting of vitamin C, vitamin E, selenium and vitamin C / vitamin E and copper / zinc ratios.

4) Method according to any one of claims 1 to 3, characterized in that the second group of biological markers contains at least four biological markers consisting of total glutathione GSH, oxidized glutathione GSSG, thiol proteins and the GSH / GSSG report.

5) Method according to any one of claims 1 to 4, characterized in that the third group of biological markers contains at least one biological marker selected from low-density LDL oxidized Oxyd oxides. and the 8 hydroxy 2 guano sine / creatinine ratio.

6) Method according to any one of claims 1 to 5, characterized in that the note of a biological marker on the scale of gravity can vary from 1 to 2 to 1 to 10 depending on the markers.