WO2019235591A1

WO2019235591A1 - Disease-state biomarker for kidney disease

Info

Publication number: WO2019235591A1
Application number: PCT/JP2019/022611
Authority: WO
Inventors: 隆志和田; 賢吾古市; 宣彦坂井; 恭宜岩田; 信治北島; 祐介中出; 健司浜瀬; 真史三田; 舞子中根; 百合香三次
Original assignee: 国立大学法人金沢大学; 株式会社資生堂
Priority date: 2018-06-07
Filing date: 2019-06-06
Publication date: 2019-12-12
Also published as: JP7471581B2; JP2019215338A; TW202016546A

Abstract

The present invention provides a saliva analysis method that includes: a step in which at least one D-form and/or L-form amino acid in saliva is measured; and a step on in which the disease state index for kidney disease is calculated on the basis of the at least one D-form and/or L-form amino acid. The present invention also provides a saliva analysis system that includes a storage unit, an input unit, an analysis and measurement unit, a data processing unit, and an output unit. The storage unit stores reference values for disease state index values for kidney disease that have been input from the input unit. The analysis and measurement unit separates and analyses at least one D-form and/or L-form amino acid in the saliva. The data processing unit calculates a disease state index value for kidney disease, on the basis of the at least one D-form and/or L-form amino acid. The data processing unit determines kidney disease by comparing against the reference values for disease state index values stored in the storage unit. The output unit outputs disease state information for kidney disease in a subject.

Description

Pathological biomarkers for kidney disease

The present invention relates to an analysis method including a step of calculating a disease state index value of kidney disease based on D-form and / or L-form of amino acids in saliva, a test method for kidney disease, and a sample that outputs disease state information about kidney disease It relates to an analysis system.

The kidney is an organ whose main role is to maintain the homeostasis of body fluids by filtering waste products and excess water in the blood and discharging them as urine. The kidneys are impaired due to immune system abnormalities, drugs, high blood pressure, diabetes, bleeding, rapid blood pressure drop, infections, dehydration associated with burns, etc., resulting in decreased kidney function. When renal function is reduced to about 60% or less due to renal disorder, it is called renal failure. Due to the difference in progression rate of renal function decrease, acute renal disorder (Acute Kidney Injury: AKI) and chronic kidney disease (Chronic Kidney Disease: CKD) ). In particular, the cause of diabetes is called diabetic kidney disease (DKD).

Acute kidney injury (AKI) refers to kidney injury that takes several hours to several weeks as the period until onset. Acute kidney injury is a condition in which renal function has rapidly declined due to causes such as ischemia, drugs, endotoxin shock, etc., such as increased blood concentrations of urea nitrogen and creatinine, internal metabolic products, abnormalities in electrolyte metabolism, acidosis, etc. Symptoms are observed, and acute kidney injury is generally diagnosed by a rapid rise in blood creatinine. Since acute kidney injury is expected to be recovered by treatment, development of a diagnostic marker capable of distinguishing earlier acute kidney injury is desired. However, since the value of blood creatinine generally used varies depending on conditions such as age, sex, muscle mass, and drugs to be taken, it cannot be said to be a specific diagnostic marker (Non-patent Document 1). Also, proteins such as neutrophil gelatinase-related lipocalin (NGAL), interleukin-18 (IL-18), nephropathy molecule (KIM-1), liver fatty acid binding proteins (FABPs), cystatin C, homovanillic acid sulfate, trimethylamine Metabolic low molecular weight compounds such as -N-oxide have been reported as markers of acute kidney injury, but development of diagnostic markers capable of detecting pathological conditions faster and more accurately than these markers is expected.

Chronic kidney disease (CKD) is a condition in which there is a decrease in renal function expressed by glomerular filtration rate due to various renal disorders, or the findings suggestive of renal disorders are chronic (more than 3 months). Say. Chronic kidney disease is a disease that affects 13.3 million people, equivalent to about 13% of the adult population in Japan, and has a high risk of end-stage renal disease (ESKD), which threatens the health of the people. There is no effective treatment for chronic kidney disease. If chronic kidney disease progresses and kidney function declines, there is a risk of uremia, which requires artificial dialysis and kidney transplantation, which is a heavy burden on the medical economy. (Non-Patent Document 2). Since chronic kidney disease progresses without subjective symptoms, diagnosis with an early diagnostic marker for renal disorder is necessary for early detection and suppression of progression of chronic kidney disease. However, the values of creatinine and urea nitrogen (BUN), which are currently widely used in clinical practice, are not satisfactory as diagnostic markers that accurately reflect the occurrence and progression of kidney damage.

In recent years, D-amino acids that were thought not to exist in mammalian organisms have been found in various tissues and are expected to have some physiological function. It has been shown that among D-amino acids in blood, the amount of D-serine, D-alanine, D-proline, D-glutamic acid, and D-aspartic acid can be a biomarker for kidney disease (non-) Patent Document 3, Non-Patent Document 4, Non-Patent Document 5, Non-Patent Document 6). Further, one or more kinds of D selected from the group consisting of D-serine, D-threonine, D-alanine, D-asparagine, D-allo-threonine, D-glutamine, D-proline and D-phenylalanine. -It is disclosed that an amino acid can be used as a disease state index value of kidney disease (Patent Document 1). In this document, blood, plasma, serum, ascites, amniotic fluid, Listed are body fluids such as lymph, saliva, semen, and urine, and excreta such as feces, sweat, and nasal discharge, and body tissues such as body hair, nails, skin tissue, and visceral tissue, but only serum and urine are actually tested. However, there is no indication that the D-form amino acid in saliva was used as a diagnostic marker.

International Publication No. 2013/140785

Since existing kidney disease markers such as creatinine and BUN values may not have sufficient sensitivity and / or specificity in clinical practice, an analysis / analysis technique for identifying a kidney disease disorder marker based on a different principle, Development of a technique for accurately determining, examining or diagnosing a disease is desired.

The present inventors have found that saliva is used as a sample, and the value based on the D-form and / or L-form of amino acids in saliva correlates with the estimated glomerular filtration rate (eGFR) and the value of blood creatinine. Invented.

Therefore, the present invention is a method for analyzing saliva of a subject,
Measuring the D-form and / or L-form of amino acids in the saliva of the subject, and calculating as a disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid, It relates to the analysis method.

In another aspect of the present invention, a method for examining kidney disease using saliva as a sample,
Measuring D-form and / or L-form of at least one amino acid in saliva;
Calculating as a disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid,
The test method further includes a step of associating a disease state index value of kidney disease with a disease state of kidney disease. Such a test method can correlate the pathological index value with the pathological condition of kidney disease by comparing the pathological index value with a reference value of a predetermined pathological index value.

In still another aspect, the present invention relates to a sample analysis system capable of performing the analysis method or the inspection method of the present invention. Such a sample analysis system includes a storage unit, an input unit, an analysis measurement unit, a data processing unit, and a disease state information output unit, and can analyze a saliva sample and output disease state information. .

In still another aspect, the present invention relates to a program that can be installed in the sample analysis system of the present invention and a storage medium that stores the program.

The value calculated based on the ratio of D-form and L-form of amino acids in saliva correlated with the estimated glomerular filtration rate and blood creatinine value. In addition, the value calculated based on one or more selected from the group consisting of the amount of D-form of amino acids in the saliva sample, the amount of L-form, and the total amount thereof is calculated between the healthy subject group and the kidney disease patient group. There was a significant difference between them. This makes it possible to diagnose kidney disease.

FIG. 1A is a scatter plot in which the ratio of lysine (Lys) D and L isomers (D / L ratio) and blood creatinine values (blood Cr) contained in the saliva of chronic kidney disease patients are plotted. It is. FIG. 1B is a scatter diagram in which a D / L ratio of histidine (His) contained in saliva of a chronic kidney disease patient and a blood creatinine value (blood Cr) are plotted. FIG. 2A is a scatter diagram in which the D / L ratio of lysine (Lys) contained in the saliva of a chronic kidney disease patient and the estimated glomerular filtration rate (eGFR) are plotted. FIG. 2B is a scatter plot in which the D / L ratio of histidine (His) contained in the saliva of a chronic kidney disease patient and the estimated glomerular filtration rate (eGFR) are plotted. FIG. 3 shows the estimated glomerular filtration rate (eGFR) in patients with chronic kidney disease, the amount of D-form of each amino acid in saliva, the amount of L-form, the total amount thereof, and the ratio of D-form to L-form (D It is the table | surface which analyzed the correlation with / L ratio. When the correlation coefficient is 0.6 or more, it can be said that the correlation is high, when it is 0.4 to 0.6, there is a correlation, and when it is 0.2 to 0.4, there is a low correlation. It can be said. FIG. 4 is a graph showing the amount of D-form amino acids contained in the saliva of healthy subjects and chronic kidney disease patients (CKD patients) for each amino acid. FIG. 5 is a graph showing the amount of L-form amino acids contained in the saliva of healthy subjects and chronic kidney disease patients (CKD patients) for each amino acid. FIG. 6 is a graph showing the total amount of D-form and L-form amino acids contained in the saliva of healthy subjects and chronic kidney disease patients (CKD patients) for each amino acid. FIG. 7 is a configuration diagram of the sample analysis system of the present invention. FIG. 8A is a flowchart illustrating an example of an operation for determining a disease state index value. FIG. 8B is a flowchart illustrating an example of an operation for determining pathological condition information and / or pathological condition index values.

The saliva analysis method according to the present invention includes the following:
Measuring the D-form and / or L-form of at least one amino acid in the saliva of the subject, and calculating the disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid;
including. The analysis method can provide data for a doctor to make a diagnosis, and can also be referred to as a preliminary diagnosis method or a diagnosis assisting method. This analysis method may further include a step of associating a disease state index value of kidney disease with a disease state of kidney disease. Such an analysis method may be performed by an analysis company or an analysis engineer to provide a result associated with the pathology of kidney disease.

The sample to be analyzed in the present invention is saliva. Saliva is a fluid secreted into the oral cavity from the salivary glands and can be collected by any method. The collected sample may be stored at room temperature, refrigerated or frozen, or may be subjected to pretreatment such as derivatization for analysis.

In the present invention, the amino acids used for calculating the disease state index value of kidney disease are preferably protein-constituting amino acids and optical isomers thereof. Examples of protein constituent amino acids include glycine, alanine, cysteine, aspartic acid, glutamic acid, phenylalanine, histidine, isoleucine, lysine, leucine, methionine, asparagine, proline, glutamine, arginine, serine, threonine, valine, tryptophan, and tyrosine. Here, since amino acids other than glycine have asymmetric carbon and optical isomers exist, and isoleucine and threonine have two asymmetric carbons, alloisomers exist. For example, isoleucine and allo-isoleucine have a relationship of D-allo-isoleucine in which the α-position of L-isoleucine is inverted, L-allo-isoleucine in which the β-position is inverted, and D-isoleucine in which the α-position and β-position are inverted. For at least one of these amino acids, the amount of D-form and / or L-form can be measured, and the disease state index value of kidney disease can be calculated based on the D-form and / or L-form of amino acid. The amino acid may be 1, or a combination of a plurality of amino acids, for example, 2 to 19 amino acids.

The disease state index value of kidney disease is a numerical value that can indicate the disease state of kidney disease, and can also be referred to as a biomarker. By comparing with a pathological index reference value determined based on a pathological index value measured in advance in a group of healthy subjects and a group of patients with kidney disease, the pathological index value of the subject can be associated with the pathological condition of kidney disease. Such a disease state index reference value can be determined as a threshold value. A person skilled in the art can appropriately set a threshold value serving as a disease condition index reference value from the condition index values of the healthy subject group and the kidney disease patient group. As the threshold value, for example, an average value, a median value, and an X percentile value of a group of healthy subjects or a group of patients with kidney disease can be used, but are not limited thereto. Here, any numerical value can be selected for X, and 3, 5, 10, 15, 20, 30, 40, 60, 70, 80, 85, 90, 95, and 97 can be appropriately used. The threshold may be one, or the pathology and cause of kidney disease (eg, drug nephropathy, diabetic nephropathy, IgA nephropathy, membranous nephropathy, nephrosclerosis, etc.), condition (early, middle term) , Late stage), as well as depending on the amino acids used or combinations thereof, and the pathological condition can be classified according to the severity. By comparing the reference value set in advance with the pathological condition index value of the subject, it becomes possible to determine, determine, or diagnose the pathological condition of the subject's kidney disease. In yet another aspect, the reference value (cut-off value) can be determined by analyzing the healthy person group and each stage.

In the present invention, the disease state index value of kidney disease is calculated based on amino acid D-form and / or L-form. More specifically, it is calculated based on the amount of D isomer, the amount of L isomer, and their total amount, or the ratio of D isomer to L isomer. The ratio of D-form and L-form of amino acid in the present invention is the ratio of D-form to the sum of D-form and L-form of amino acid, the ratio of L-form to the sum of D-form and L-form, and the ratio of L-form to D-form It may be a ratio or a ratio of D body to L body. As long as it is used as a kidney disease marker, the pathological index value may be corrected by addition, subtraction, integration, and / or division. In that case, any age, weight, sex, BMI, GFR, etc. Variables may be used.

When the amount of D form of amino acid is used as an index, from the correlation with estimated glomerular filtration rate (eGFR) (| r |> 0.2), from glutamic acid, alanine, lysine, histidine, aspartic acid, proline, and serine It is preferable to calculate the disease state index value using the D-form amount of an amino acid selected from the group consisting of: From the viewpoint that the correlation with eGFR is higher (| r |> 0.4), using the amount of D form of an amino acid selected from the group consisting of glutamic acid, alanine, lysine, histidine, aspartic acid, and proline, More preferably, the disease state index value is calculated. From the viewpoint that the correlation with eGFR is higher (| r |> 0.6), the pathological index value is calculated using the amount of D-form of an amino acid selected from the group consisting of glutamic acid, alanine, lysine and proline. Even more preferred.

When the amount of amino acid L-form is used as an index, glutamic acid, threonine, proline, lysine, histidine, serine, glutamine, aspartic acid are correlated with the estimated glomerular filtration rate (eGFR) (| r |> 0.2). It is preferable to calculate a disease state index value using the amount of L-form of an amino acid selected from the group consisting of glycine, alanine, valine, leucine, and tyrosine. From the viewpoint of higher correlation with eGFR (| r |> 0.4), the pathologic index value is calculated using the amount of L-form of an amino acid selected from the group consisting of glutamic acid, threonine, proline and lysine More preferably.

When the total amount of amino acids D-form and L-form is used as an index, from the correlation with the estimated glomerular filtration rate (eGFR) (| r |> 0.2), glutamic acid, threonine, proline, lysine, It is preferable to calculate the pathological condition index value using the total amount of D-form and L-form of amino acids selected from the group consisting of histidine, serine, glutamine, aspartic acid, glycine, alanine, valine, leucine, and tyrosine. From the viewpoint of higher correlation with eGFR (| r |> 0.4), the total amount of D-form and L-form of amino acids selected from the group consisting of glutamic acid, threonine, proline, lysine and alanine is used. More preferably, the disease state index value is calculated.

When the ratio of D-form to L-form is used as an index, from the correlation with estimated glomerular filtration rate (eGFR) (| r |> 0.2), amino acids are histidine, lysine, aspartic acid, glutamic acid, alanine, and It is preferable to calculate the disease state index value using at least one amino acid selected from the group consisting of proline. From the viewpoint that the correlation with eGFR is higher (| r |> 0.4), the amino acid is at least one amino acid selected from the group consisting of histidine, lysine, aspartic acid, alanine, and proline. More preferably, the index value is calculated. From the viewpoint of higher correlation with eGFR (| r |> 0.6), it is more preferable to use at least one amino acid selected from the group consisting of histidine, lysine, proline and alanine. A combination of two or more selected from the group consisting of histidine, lysine, proline and alanine, that is, histidine and lysine, histidine and proline, histidine and alanine, lysine and proline, lysine and alanine, proline and alanine, or histidine and lysine A combination of proline and alanine can also be used.

On the other hand, from the viewpoint of having a significant difference between healthy subjects and patients with chronic kidney disease, the amounts of D-aspartic acid, D-glutamic acid, D-alanine, D-proline, and L-histidine, L-serine, L- Glutamine, L-aspartic acid, glycine, L-glutamic acid, L-threonine, L-alanine, L-proline, L-valine, L-isoleucine, L-leucine, amount of L-tyrosine, and (D + L) -histidine, (D + L) -serine, (D + L) -glutamine, (D + L) -aspartic acid, (D + L) -glutamic acid, (D + L) -threonine, (D + L) -alanine, (D + L) -proline, (D + L) -valine, ( D + L) -isoleucine, (D + L) -leucine, (D + L) -tyrosine, and threonine and isoleucine allo Therefore, the amount of D-threonine + L-allo-threonine, D-allo-threonine + L-threonine, D-isoleucine + L-allo-isoleucine, D-allo-isoleucine + L-isoleucine can be calculated as a disease state index value. preferable.

The measurement of D-amino acid and L-amino acid in a sample in the present invention may be carried out using any method known to those skilled in the art. For example, enzymatic methods (Y. Nagata et al., Clinical Science, 73 (1987), 105. Analytical Biochemistry, 150 (1985), 238., A. D'Aniello et al., Comparative Biochemistry and Physiology Part B, 66 (1980), 319. Journal of Neurochemistry, 29 (1977), 1053., A. Berneman et al., Journal of Microbial & Biochemical Technology, 2 (2010), 139., W. G. Gutheil et al., Analy. Biochemistry, 287 (2000), 196., G. Molla et al., Methods in Molecular Biology, 794 (2012), 273., T. Ito et al., Analytical Biochemistry, 371 (2007), 167., etc.) Antibody method (T. Ohgusu et al., Analytical Biochemistry, 357 (2006), 15., etc.), Gas chromatography (GC) (H. Hasegawa et al., Journal of Mass Spectrometry, 46 (2011), 502. , M. C. Waldhier et al., Analytical and Bioanalytical Chemistry, 394 (2009), 695., A. Hashimoto, T. Nishikawa et al., FEBS Letters, 296 (1992), 33., H. Bruckn er and A. Schieber, Biomedical Chromatography, 15 (2001), 166., M. Junge et al., Chirality, 19 (2007), 228., M. C. Waldhier et al., Journal of Chromatography A, 12 2011), 4537. etc.), capillary electrophoresis (CE) (H.） Miao et al., Analytical Chemistry, 77 (2005), 7190., D. L. Kirschner et al., Analytical Chemistry, 79 (2007) , 736., F. Kitagawa, K. Otsuka, Journal of Chromatography B, 879 (2011), 3078., G. Thorsen and J. Bergquist, Journal of Chromatography B, 745 (2000), 389. etc.), liquid Chromatography (HPLC) (N. Nimura and T. Kinoshita, Journal of Chromatography, 352 (1986), 169., A. Hashimoto et al., Journal of Chromatography, 582 (1992), 41., H. Bruckner et al ., Journal of Chromatography A, 666 (1994), 259., N. Nimura et al., Analytical Biochemistry, 315 (2003), 262., C. Muller et al., Journal of Chromatograph y A, 1324 (2014), 109., S. Einarsson et al., Analytical Chemistry, 59 (1987), 1191. E. Okuma and H. Abe, Journal of Chromatography B, 660 (1994), 243., Y. Gogami et al., Journal of Chromatography B, 879 (2011), 3259., Y. Nagata et al., Journal of Chromatography, 575 (1992), 147., S. A. Fuchs et al., Clinical Chemistry , 54 (2008), 1443., D. Gordes et al., Amino Acids, 40 (2011), 553., D. Jin et al., Analytical Biochemistry, 269 (1999), 124., J. Z. Min et al., Journal of Chromatography B, 879 (2011), 3220., T. Sakamoto et al., Analytical and Bioanalytical Chemistry, 408 (2016), 517., W. F. Visser et al., Journal ofChromatic , 1218 (2011), 7130., Y. Xing et al., Analytical and Bioanalytical Chemistry, 408 (2016), 141., K. Imai et al., Biomedical Chromatography, 9 (1995), 106., T. Fukushima et al., Biomedical Chromatography, 9 (1995), 10., R. J . Reischl et al., Journal of Chromatography A, 1218 (2011), 8379., R. J. Reischl and W. Lindner, Journal of Chromatography A, 1269 (2012), 262., S. Karakawa et.al. of Pharmaceutical and Biomedical Analysis, 115 (2015), 123, etc.).

The optical isomer separation analysis system in this specification may combine a plurality of separation analyses. More specifically, passing a sample containing components having optical isomers along with a first liquid as a mobile phase through a first column filler as a stationary phase to separate the components of the sample; Individually holding each of the components of the sample in a multi-loop unit, each of the components of the sample individually held in the multi-loop unit as a stationary phase together with a second liquid as a mobile phase Supplying the second column packing material having an optically active center through a flow path to split the optical isomers contained in each of the sample components, and the optical isomerism contained in each of the sample components The D- / L-amino acid concentration in the sample can be measured by using an optical isomer analysis method characterized by including a step of detecting a body ( Patent No. 4,291,628). Alternatively, D-amino acids can be measured by immunological techniques using monoclonal antibodies that identify optical isomers of amino acids, such as monoclonal antibodies that specifically bind to D-leucine, D-aspartic acid, etc. (Japanese Patent Application No. 2008-27650). Further, when the total amount of D-form and L-form is used as an index, it is not necessary to separate and analyze D-form and L-form, and amino acids can be analyzed without distinguishing D-form and L-form. In that case, it can be separated and quantified by enzymatic method, antibody method, GC, CE, and HPLC.

In the present invention, kidney disease refers to all the states in which the kidney is damaged. Causes of decreased renal function include multiple factors such as immune system abnormalities, drugs, high blood pressure, diabetes, bleeding, rapid blood pressure decrease, infection, dehydration associated with burns, and the like. Acute kidney injury (AKI) has been proposed for stage classification such as RIFLE classification, AKIN classification, and KDIGO classification. Acute kidney injury is classified into Risk (stage 1), Injury (stage 2), Failure (stage 3), Furthermore, it classified into Loss and End stage kidney disease according to the duration. All of these classifications are based on the amount of blood creatinine and the amount of urine. For example, in Risk (stage 1), blood creatinine increases 1.5 to 2.0 times from the baseline or 0 The urine volume of less than 5 ml / kg / hour is 6 hours or more. In Injury (Stage 2), blood creatinine increases 2.0 to 3.0 times from the baseline, or 0.5 ml / kg. The urine volume of less than 12 hours / hour is 12 hours or more, and in Failure (stage 3), blood creatinine increases 3.0 times or more from the baseline, or urine volume of less than 0.3 ml / kg / hour The criterion is 24 hours or more. On the other hand, these classifications make it possible to classify acute kidney injury more accurately by using another index, for example, a change amount of GFR in combination. As for chronic kidney disease (CKD), the diagnostic criteria for stage 1 (normal renal function, eGFR ≧ 90) to stage 5 (renal failure, eGFR <15) are shown in the Japanese Society of Nephrology guidelines (2013 revision) Yes. The estimated glomerular filtration rate (eGFR), which is an index here, is calculated from the value of blood creatinine, age, and sex, and can represent the degree of progression of kidney disease. In the analysis / inspection method of the present invention, kidney disease is detected based on a principle different from that of conventional kidney disease markers. Further, by using in combination with blood creatinine, GFR, etc., it becomes possible to distinguish and diagnose kidney disease in more detail.

In another aspect of the present invention, the present invention relates to a method for examining kidney disease using saliva as a sample. This inspection method includes the following steps:
Measuring D-form and / or L-form of at least one amino acid in saliva;
Calculating as a disease state index value of kidney disease based on D-form and / or L-form of the at least one amino acid,
The method further includes the step of associating a disease state index value of kidney disease with a disease state of kidney disease. In the associating step, the pathological condition index value and the pathological condition of kidney disease can be associated by comparing the pathological condition index value with a predetermined reference value of the pathological condition index value. The test method of the present invention may be performed by an analysis company or an analysis engineer to provide a result associated with the pathology of kidney disease. The sample used in the test method, the associated renal disease pathology, and each step performed may be the same as defined in the analytical method.

FIG. 8 is a configuration diagram of the sample analysis system of the present invention. The sample analysis system 10 of the present invention shown in FIG. 8 is configured so that the analysis method and the inspection method of the present invention can be performed. Such a sample analysis system 10 includes a storage unit 11, an input unit 12, an analysis measurement unit 13, a data processing unit 14, and an output unit 15, and analyzes a saliva sample and outputs pathological condition information. be able to. More specifically, in the sample analysis system 10 of the present invention,
The storage unit 11 stores a reference value of a disease state index value for determining kidney disease input from the input unit 12,
The analytical measurement unit 13 separates and measures an optical isomer of at least one amino acid among the amino acids in the saliva sample of the subject,
The data processing unit 14 calculates a disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid,
The data processing unit 14 determines the pathological information of kidney disease by comparing with the reference value stored in the storage unit 11,
The output unit 15 can output pathological information about the kidney disease of the subject.

The storage unit 11 includes a memory device such as a RAM, a ROM, and a flash memory, a fixed disk device such as a hard disk drive, or a portable storage device such as a flexible disk and an optical disk. The storage unit stores data measured by the analysis measurement unit, data and instructions input from the input unit, calculation processing results performed by the data processing unit, etc., as well as computer programs and databases used for various processes of the information processing apparatus. Remember. The computer program may be installed via a computer-readable recording medium such as a CD-ROM or DVD-ROM, or via the Internet. The computer program is installed in the storage unit using a known setup program or the like.

The input unit 12 is an interface or the like, and includes operation units such as a keyboard and a mouse. As a result, the input unit can input data measured by the analysis measurement unit 13, instructions for calculation processing performed by the data processing unit 14, and the like. For example, when the analysis measurement unit 13 is outside, the input unit 12 may include an interface unit that can input measured data or the like via a network or a storage medium, separately from the operation unit.

Analytical measurement unit 13 performs a process of measuring the amount of D-form and / or L-form of amino acid in the saliva sample. Therefore, it is preferable that the analytical measurement unit 13 has a configuration that enables separation and measurement of D-form and L-form of amino acids, but when measuring only the total amount, the D-form and L-form are not separated. It is also possible to measure together. Amino acids may be analyzed one by one, but some or all types of amino acids may be analyzed together. The analytical measurement unit 13 is not intended to be limited to the following, but may be a high performance liquid chromatography system including a sample introduction unit, an optical resolution column, and a detection unit, for example. The analysis measurement unit 13 may be configured separately from the sample analysis system, and the measured data or the like may be input via the input unit 12 using a network or a storage medium.

The data processing unit 14 calculates the D-form amount, the L-form quantity, the total amount of the D-form and the L-form, or the ratio of the D-form and the L-form from the measured D-form and L-form measurements of each amino acid. Based on this, a pathological condition index value of kidney disease is calculated and compared with a reference value stored in the storage unit 11 to determine kidney disease. The data processing unit 14 performs various arithmetic processes on the data measured by the analysis measurement unit 13 and stored in the storage unit 11 in accordance with a program stored in the storage unit. Arithmetic processing is performed by a CPU included in the data processing unit. The CPU includes a functional module that controls the analysis measurement unit 13, the input unit 12, the storage unit 11, and the output unit 15, and can perform various controls. Each of these units may be configured by an independent integrated circuit, a microprocessor, firmware, and the like.

The output unit 15 is configured to output a pathological condition index value and / or pathological condition information, which is a result of performing arithmetic processing in the data processing unit. The output unit 15 may be a display device such as a liquid crystal display that directly displays the result of the arithmetic processing, an output unit such as a printer, or an interface unit for outputting to an external storage device or via a network. There may be.

FIG. 8A is a flowchart showing an example of a procedure for determining a disease state index value by the program of the present invention, and FIG. 8B shows an example of an operation for determining a disease state index value and / or disease state information by the program of the present invention. It is a flowchart which shows.
Specifically, the program of the present invention is a program that causes an information processing apparatus including an input unit, an output unit, a data processing unit, and a storage unit to determine a pathological condition index value and / or pathological condition information. The program of the present invention is as follows:
Storing the measured value of D-form and / or L-form of at least one amino acid input from the input unit in the storage unit;
Based on the value stored in the storage unit, the data processing unit calculates a disease state index value,
A command for causing the information processing apparatus to store the calculated pathologic index value in the storage unit and cause the output unit to output the stored pathologic index value; The program of the present invention may be stored in a storage medium or provided via an electric communication line such as the Internet or a LAN.

When the information processing apparatus includes an analysis measurement unit, instead of inputting measurement values of at least one amino acid D-form and L-form from the input unit, the analysis measurement unit measures the measurement value from the saliva sample and stores it in the storage unit. A command for causing the information processing apparatus to execute the storage may be included.

In determining the pathological information,
By causing the data processing unit to compare the stored disease state index value and the reference value stored in the storage unit in advance, the disease state of the kidney disease is determined,
A command for causing the information processing apparatus to store the determined disease state information in the storage unit and cause the output unit to output the stored disease state information may be included.

In the present invention, the subject is not limited to humans, and may include laboratory animals such as mice, rats, rabbits, dogs, monkeys, and the like. In the most preferred embodiment, the analysis method and test method of the present invention can be performed for a definitive diagnosis on a subject who has subjective symptoms of kidney disease or a subject suspected of having kidney disease. It can also be implemented as a health checkup for subjects who have no subjective symptoms.

The analysis method of the present invention can be used to collect preliminary data for a method for diagnosing chronic kidney disease and / or acute kidney injury. A doctor can diagnose chronic kidney disease and / or acute kidney injury using such preliminary data, but such an analysis method may be performed by a medical assistant or the like who is not a doctor. Etc. can also be performed. Therefore, it can be said that the analysis method of the present invention is a preliminary method or an auxiliary method of diagnosis. In a more preferred embodiment, the analysis method of the present invention is performed on a saliva sample collected in a health examination.

Referring to the result of the test by the analysis method of the present invention makes it possible to classify the severity of kidney disease. As an example, it can classify | categorize according to six severity of G1, G2, G3a, G3b, G4, and G5 which is a classification | category of a chronic kidney disease patient. A therapeutic intervention is performed on subjects classified into the categories corresponding to G2 to G5. Depending on each category, treatment intervention can be selected as appropriate. As for the therapeutic intervention, lifestyle improvement, dietary guidance, blood pressure management, anemia management, electrolyte management, uremic toxin management, blood glucose level management, immune management, lipid management, etc. are guided independently or in combination. As lifestyle improvement, smoking cessation and reduction of BMI value to less than 25 are recommended. As dietary guidance, salt reduction and protein restriction are performed. Among these, in particular, blood pressure management, anemia management, electrolyte management, uremic toxin management, blood glucose level management, immune management, and lipid management can be treated by medication. As blood pressure management, the blood pressure is controlled to be 130/80 mmHg or less, and a hypertension therapeutic drug may be administered depending on the case. Antihypertensive drugs include diuretics (thiazide diuretics such as trichlormethiazide, benchyl hydrochlorothiazide, hydrochlorothiazide, thiazide-like diuretics such as methiclan, indamide, tribamide, meflucid, loop diuretics such as furosemide, potassium retention Diuretics and aldosterone antagonists such as triamterene, spironolactone, eplerenone, etc., calcium antagonists (dihydropyridines such as nifedipine, amlodipine, efonidipine, cilnidipine, nicardipine, nisoldipine, nitrendipine, nilvadipine, varnidipine, felidipine, manidipine, manidipine, manidipine, manidipine, Alanidipine, benzothiazepine, diltiazem, etc.), angiotensin converting enzyme inhibitor (captop) , Enalapril, acelapril, delapril, cilazapril, lisinopril, benazepril, imidapril, temocapril, quinapril, trandolapril, verindopril erbumine, etc.), angiotensin receptor antagonist (angiotensin II receptor antagonist such as losartan, candesartan, Valsartan, telmisartan, olmesartan, irbesartan, azilsartan, etc.), sympathetic blockers (β-blockers such as atenolol, bisoprolol, betaxolol, metoprolol, acetrol, ceriprolol, propranolol, nadolol, carteolol, pindolol, aiprazolol , Arotinolol, carvedilol, labetalol, bevantolol, urapidil, terazosin, brazosi , Doxazosin, bunazosin, etc.) can be used. As an anemia treatment agent, erythropoietin preparation, iron agent, HIF-1 inhibitor and the like are used. Calcium receptor agonists (such as cinacalcet and ethercalcetide) and phosphorus adsorbents are used as electrolyte regulators. Activated carbon or the like is used as the uremic toxin adsorbent. The blood glucose level is managed to be less than 6.9% of Hba1c, and a hypoglycemic drug is sometimes administered. SGLT2 inhibitors (ipragliflozin, dapagliflozin, luceogliflozin, tofogliflozin, canagliflozin, empagliflozin, etc.), DPP4 inhibitors (sitagliptin phosphate, vildagliptin, saxagliptin, alogliptin, linagliptin, trenagliptin, trelagliptin , Anagliptin, omalipliptin, etc.), sulfonylurea drugs (tolbutamide, acetohexamide, chlorpropamide, glyclopyramide, glibenclamide, gliclazide, glimepiride, etc.), thiazolidine drugs (pioglitazone, etc.), biguanide drugs (metformin, buformin, etc.), α ―Glucosidase inhibitors (Acarbose, voglibose, miglitol, etc.), Glinide drugs (nateglinide, mitiglinide, Glinides, etc.) insulin preparations, NRF2 activator (Bardo Kiso Lung methyl, etc.) and the like. For immunological management, immunosuppressants (steroids, tacrolimus, anti-CD20 antibody, cyclohexamide, mycophenolate mofetil (MMF), etc.) are used. In lipid management, LDL-C is controlled to be less than 120 mg / dL, and sometimes treatments for dyslipidemia such as statins (rosuvastatin, pitavastatin, atorvastatin, cerivastatin, fluvastatin, simvastatin, pravastatin, lovastatin, mevastatin, etc.), Fibrate drugs (clofibrate, bezafibrate, fenofibrate, clinofibrate, etc.), nicotinic acid derivatives (tocolol nicotinate, nicomol, niceritrol, etc.), cholesterol transporter inhibitors (eg ezetimibe etc.), PCSK9 inhibitors (eg ebolokumab etc.) EPA A preparation or the like is used. Any drug may be used as a single agent or a combination. Depending on the degree of decrease in renal function, renal replacement therapy such as peritoneal dialysis, hemodialysis, continuous hemofiltration dialysis, blood apheresis (plasma exchange, plasma adsorption, etc.) and kidney transplantation may be performed.

All documents mentioned in this specification are incorporated herein by reference in their entirety.

The embodiments of the present invention described below are for illustrative purposes only and are not intended to limit the technical scope of the present invention. The technical scope of the present invention is limited only by the appended claims. Modifications of the present invention, for example, addition, deletion, and replacement of the configuration requirements of the present invention can be made on the condition that the gist of the present invention is not deviated.

Materials and methods
Research Ethics All experiments were conducted in accordance with the guidelines of the “Declaration of Helsinki (revised at the WMA Fortaleza General Assembly in October 2013)” and “Ethics Guidelines for Medical Research on Humans (Promulgated on December 22, 2014)” .

Material amino acid enantiomers and HPLC grade acetonitrile were purchased from Nacalai Tesque (Kyoto). HPLC grade methanol, trifluoroacetic acid, boric acid and the like were purchased from Wako Pure Chemical (Osaka). The water was purified using a Mill-Q gradient A10 system.

As a sample saliva sample, 5 ml of saliva was collected 2 hours after brushing from a subject who had brushed his teeth after breakfast. Saliva was collected from the entire oral cavity. The collected saliva was stored at 4 ° C. or −80 ° C. under anaerobic conditions until the experiment. A blood sample was collected from the same subject.

The analyzed saliva sample was subjected to an amino acid optical isomer analysis system using a D, L-amino acid simultaneous high sensitivity analysis system (Patent No. 4291628) developed by Zaitsu et al. Details of the analysis conditions for each amino acid are described in Miyoshi Y. et al. , Et al. Chromatogr. B, 879: 3184 (2011) and Sasabe, J. et al. Et al., Proc. Natl. Acad. Sci. U. S. A. 109: 627 (2012). Briefly, 5 μl of an anhydrous methyl cyanide solution of NBD-F (4-fluoro-7-nitro-2,1,3-benzoxadiazole, Tokyo Chemical Industry Co., Ltd.) is added to the saliva sample, Heated at 0 ° C. for 2 minutes. After the reaction, 75 μl of 2% (v / v) aqueous trifluoroacetic acid solution was added. 2 μL of this mixed solution was subjected to an HPLC system (NANOSPACE SI-2, Shiseido Co., Ltd.). Briefly, an in-house manufactured monolithic ODS column (inner diameter 0.53 mm × 500 mm) kept at 40 ° C. was used as the analytical column for reverse phase separation. The mobile phase was methyl cyanide-trifluoroacetic acid-water (volume ratio 5: 0.05: 95). The flow rate was 35 μL per minute. Fluorescence detection was performed with an excitation wavelength of 470 nm and a detection wavelength of 530 nm. After reverse phase separation, it was subjected to an optical isomer separation system. For the optical isomer separation, a Sumichiral OA-2500S column (250 mm × 1.5 mm, self-packing, material is manufactured by Sumika Chemical Analysis Co., Ltd.) using (S) -naphthylglycine as a chiral selector was used. The two-dimensional HPLC system described in this example can quantitatively measure in the range of 1 fmol to 100 pmol, for example, by distinguishing optical isomers of serine in a biological sample. This was sufficient sensitivity to discriminate changes in the concentrations of histidine and lysine D-form and L-form in healthy subjects and kidney disease patients. From the measured values of the D-form amino acid and the L-form amino acid, the D-form amino acid concentration, the L-form amino acid concentration, the total concentration of the D-form and the L-form, and the D / L ratio were calculated. FIGS. 4 to 6 show the concentrations of D-form, L-form, and total D-form and L-form of amino acids in healthy subjects and chronic kidney disease patients, respectively. Note that glycine does not have an asymmetric carbon and therefore does not have an optical isomer. However, for convenience, glycine is represented as an L-amino acid category.

Serum creatinine was measured by an enzyme method for the obtained blood sample. The estimated glomerular filtration rate (eGFR) was determined based on the measured serum creatinine value and age. The formula for determining eGFR is as follows:

{In the formula, the unit of age is year, the unit of SCr is mg / dL, and the unit of estimated glomerular filtration rate (eGFR) is mL / min / 1.73 m ² body surface}.
For female patients, a correction factor of 0.739 was applied to the calculated value of the mathematical formula.
The relationship between the subject's eGFR value, the amount of D-form amino acids, the amount of L-form amino acids, the total amount thereof, and the ratio of D-form to L-form for each of the 22 types of amino acids, and Pearson's product-moment correlation coefficient (Pearson's product-moment correlation coefficient) was used to analyze the correlation. The result is shown in FIG.

When the relationship between the obtained serum creatinine value and the D / L-lysine ratio and D / L-histidine ratio was analyzed, a high correlation was found (r = 0.762, p = 0.046 and r = 0.762, p = 0.046). Analysis of the relationship between the estimated glomerular filtration rate obtained and the D / L-lysine ratio and D / L-histidine ratio revealed a high negative correlation (r = −0.926, p = 0). .003 and r = −0.749, p = 0.053). Graphs showing correlations between serum creatinine values and D / L-lysine ratio and D / L-histidine ratio are shown in FIGS. 2A and 2B are graphs showing correlations between the estimated glomerular filtration rate and the D / L-lysine ratio and D / L-histidine ratio. An unpaired t-test (Student's t-test) was performed for comparison between the two groups, and statistical significance was measured.

Claims

A method for analyzing saliva,
Analyzing the D-form and / or L-form of at least one amino acid in saliva, and calculating as a disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid Method.
The renal disease state index value is a ratio of D-form to the sum of D-form and L-form of the at least one amino acid, ratio of L-form to sum of D-form and L-form, ratio of L-form to D-form, or The analysis method according to claim 1, which is a ratio of D-form to L-form.
The analysis method according to claim 2, wherein the amino acid is selected from the group consisting of lysine, proline, histidine, alanine, aspartic acid, and glutamic acid.
The analysis method according to claim 3, wherein the amino acid is selected from the group consisting of lysine, proline, histidine, and alanine.
The analysis method according to claim 1, wherein the disease state index value of the kidney disease is selected from the group consisting of the amount of D form of the at least one amino acid, the amount of L form, and the total amount thereof.
The analysis method according to claim 5, wherein the amino acid is selected from the group consisting of histidine, serine, glutamine, aspartic acid, glycine, glutamic acid, threonine, alanine, proline, valine, isoleucine, leucine, tyrosine, and lysine.
The pathological index value is D-glutamic acid amount, D-alanine amount, D-lysine amount, D-histidine amount, D-aspartic acid amount, D-proline amount, L-glutamic acid amount, L-threonine amount, L-proline. Selected from the group consisting of: quantity, L-lysine quantity, (D + L) -glutamic acid quantity, (D + L) -threonine quantity, (D + L) -proline quantity, (D + L) -lysine quantity, and (D + L) -alanine quantity. Item 7. The analysis method according to Item 6.
The analysis method according to claim 7, wherein the disease state index value is selected from the group consisting of a D-glutamic acid amount, a D-alanine amount, a D-lysine amount, and a D-proline amount.
The analysis method according to any one of claims 1 to 8, wherein the analysis method further includes a step of associating a disease state index value of kidney disease with a disease state of kidney disease.
The step of associating the pathological index value of kidney disease with the pathological condition of kidney disease is determined based on the pathological index value determined from the pathological index value of the healthy group and the pathological index value of the patient group of kidney disease. The analysis method according to claim 9.
A saliva analysis system including a storage unit, an input unit, an analysis measurement unit, a data processing unit, and an output unit,
The storage unit stores a reference value of a disease state index value of kidney disease input from the input unit,
The analytical measurement unit separates and measures D-form and / or L-form of at least one amino acid in the saliva;
The data processing unit calculates a disease state index value of kidney disease based on the D-form and / or L-form of the at least one amino acid,
The data processing unit determines kidney disease by comparing with a reference value of a disease state index value stored in a storage unit,
The analysis system, wherein the output unit outputs pathological information about kidney disease of a subject.
The renal disease state index value is a ratio of D-form to the sum of D-form and L-form of the at least one amino acid, ratio of L-form to sum of D-form and L-form, ratio of L-form to D-form, or The analysis system according to claim 11, wherein the analysis system is a ratio of D body to L body.
The analysis system according to claim 12, wherein the amino acid is selected from the group consisting of lysine, proline, histidine, alanine, aspartic acid, and glutamic acid.
The analysis system according to claim 13, wherein the amino acid is selected from the group consisting of lysine, proline, histidine, and alanine.
12. The analysis system according to claim 11, wherein the disease state index value of the kidney disease is the amount of D-form, the amount of L-form, and the total amount of the at least one amino acid.
The analysis system according to claim 15, wherein the amino acid is selected from the group consisting of histidine, serine, glutamine, aspartic acid, glycine, glutamic acid, threonine, alanine, proline, valine, isoleucine, leucine, tyrosine, and lysine.
The pathological index value is D-glutamic acid amount, D-alanine amount, D-lysine amount, D-histidine amount, D-aspartic acid amount, D-proline amount, L-glutamic acid amount, L-threonine amount, L-proline. Selected from the group consisting of: quantity, L-lysine quantity, (D + L) -glutamic acid quantity, (D + L) -threonine quantity, (D + L) -proline quantity, (D + L) -lysine quantity, and (D + L) -alanine quantity. Item 17. The analysis system according to Item 16.
The analysis system according to claim 17, wherein the disease state index value is selected from the group consisting of an amount of D-glutamic acid, an amount of D-alanine, an amount of D-lysine, and an amount of D-proline.