WO2015098474A1

WO2015098474A1 - Serum uric acid-reducing agent having rice protein as active ingredient

Info

Publication number: WO2015098474A1
Application number: PCT/JP2014/082385
Authority: WO
Inventors: 斎藤　亮彦; 康宏細島; 基二門脇; 真敏久保田; 幹夫藤井; 葉月近藤
Original assignee: 亀田製菓株式会社
Priority date: 2013-12-24
Filing date: 2014-12-08
Publication date: 2015-07-02
Also published as: JPWO2015098474A1; JP2016172693A; JP6088071B2

Abstract

With increases in westernization of diet and alcohol consumption, the number of patients with hyperuricemia is increasing year by year. Although uric acid production-inhibiting drugs, uric acid excretion-promoting agents, etc. are being implemented, concern about side effects in those with renal dysfunction and risks of urolithiasis, etc. have become problematic. A material that has uric acid-reducing effects and can be taken daily was desired. It has been found that rice endosperm protein has human serum uric acid-reducing effects. Because serum uric acid-reducing agents having rice endosperm protein as an active ingredient are derived from rice and anticipated to be very safe and are able to reduce serum uric acid levels by daily ingestion thereof, said serum uric acid-reducing agents are effective for prevention/treatment of hyperuricemia and gout.

Description

Serum uric acid lowering agent containing rice protein as active ingredient

The present invention relates to a serum uric acid lowering agent containing a protein extracted from polished rice as an active ingredient.

Uric acid is the final metabolite of purines in humans, and is produced by the degradation of ATP and metabolism of nucleic acids in food, and finally excreted in urine. Usually, the production and excretion of uric acid is balanced, but if the balance is lost due to an increase in production or a decrease in excretion, and the serum uric acid level exceeds 7 mg / dl, it is defined as hyperuricemia. If it continues, it is said that the risk of gout attacks is high. Hyperuricemia was once a rare disease in Japan, but the number of patients has increased year by year due to factors such as westernization of diet and increased alcohol intake, and the current number of patients is estimated to reach more than 10 million. Has been. It has been pointed out that hyperuricemia not only causes gout but also causes gout kidneys and may increase the risk of cardiovascular and cerebrovascular disorders. Treatment of hyperuricemia is mainly dietary and exercise therapy in patients without gout attacks or complications. However, it is not easy to continue dietary restrictions and exercise such as avoiding high-pudding diets.

In addition, so far, allopurinol, a uric acid production inhibitor, and benzbromarone, a uric acid excretion promoter, have been put to practical use as agents that lower serum uric acid levels. However, allopurinol is required to be administered with caution because it may cause side effects in patients with renal impairment, and uric acid excretion-promoting drugs have been pointed out risks such as urinary calculi. Therefore, if there is a food material that has the effect of lowering the blood uric acid level and can be easily taken into a normal meal, it can be a very useful prevention / treatment method for gout attacks and hyperuricemia-related diseases.

Similar needs exist for diseases such as gout attacks, renal disease, cardiovascular and cerebrovascular disorders caused by monocyte chemotactic protein-1 induced by uric acid.

By the way, the main components of proteins contained in rice endosperm are easily digestible glutelin, globulin, albumin and indigestible prolamin. As a method of producing a protein composition extracted from rice endosperm, heat-resistant amylase is allowed to act on polished rice or rice flour, and the remaining protein is recovered as a precipitate (enzyme-treated rice protein), A method (alkaline-extracted rice protein) in which protein extracted by adding an alkaline solution is acid-precipitated and recovered is known. It has been reported that the protein utilization efficiency as a nutrient is significantly higher in the latter than in the former, and the protein utilization efficiency is comparable to casein (Non-patent Document 1).

An object of the present invention is to provide a serum uric acid lowering agent, a food and a medicine which have a blood uric acid level lowering action and can be taken on a daily basis.

Another object of the present invention is to reduce the risk of diseases that can be taken on a daily basis and suppress gout attacks, renal diseases, cardiovascular disorders and cerebrovascular disorders caused by monocyte chemotactic protein-1, Another object is to provide a monocyte chemotactic protein-1 expression-lowering agent and a high-density lipoprotein cholesterol enhancer.

As a result of various studies to solve the above problems, the present inventors have found that alkali-extracted rice protein has an effect of lowering human serum uric acid level, and have completed the present invention. In addition, intake of rice protein increases high-density lipoprotein cholesterol (HDL-cholesterol) in the blood, and monocyte chemotactic protein-1 (MCP-1), which is one of inflammatory chemokines. ) Was found to decrease the blood concentration.

That is, the present invention is a serum uric acid lowering agent containing rice endosperm protein as an active ingredient, and also decreases monocyte chemotactic protein (MCP) -1 induced by uric acid or high density lipoprotein cholesterol (HDL- It is an agent for reducing the risk of gout attacks associated with hyperuricemia, renal diseases such as gout kidney, and cardiovascular / cerebrovascular disorder through the reduction of MCP-1 induced by an increase in cholesterol.

Furthermore, the present invention includes a serum uric acid lowering agent having a serum uric acid level lowering action as described above, and an agent for reducing the risk of renal diseases such as gout attacks, gouty kidneys, and cardiovascular / cerebrovascular disorders through the reduction of MCP-1. , Pharmaceutical or food.

Preferably, the rice endosperm protein is obtained by drying a protein recovered by extraction from rice endosperm with an alkali and then precipitation with an acid.

It is known that MCP-1 is involved in the induction of various inflammations such as obesity, diabetes, cardiovascular disorders, diabetic nephropathy and diabetic retinitis (Panee et al., Cytokine Vol. 60, 1-12). (2012)). It is also known that blood MCP-1 levels are higher in patients with hyperuricemia than those with normal uric acid levels, and uric acid induces production of MCP-1 (Kanellis et al., Hypertension No. 1). 41, 1287-1293 (2003), Grainger et al., Rheumatology (Oxford) 52, 1018-1102 (2013)). HDL-cholesterol has also been reported to suppress the production of MCP-1 induced by uric acid (Acan et al., Arthritis Res Ther, Vol. 12, R23 (2010)).
Ingestion of rice protein not only lowers serum uric acid level but also suppresses uric acid-induced MCP-1 production directly or through an increase in HDL-cholesterol, leading to gout, gouty kidney and cardiovascular disorders This contributes to lower risk.
The serum uric acid lowering agent of the present invention is expected to be highly safe due to abundant dietary experience in rice, and since it can lower serum uric acid level by daily intake, it prevents hyperuricemia and gout・ It is extremely effective for treatment.

It is a figure which shows the change of the blood uric acid level accompanying the intake of rice protein (stratified analysis of the blood uric acid value top 6 persons), * mark is significant at 5% of the risk rate compared with the value before ingestion. It shows that. It is a figure which shows the change of the blood uric acid level accompanying the intake of rice protein (stratification analysis of the top 7 urine uric acid / creatinine ratios), and * and ** are respectively a risk factor 5 compared with the value before ingestion. % And 1% are significant.

Hereinafter, a composition containing rice protein alkali-extracted from rice endosperm is abbreviated as “rice endosperm protein”. Any variety of rice may be used for protein extraction. Rice endosperm protein can be extracted with alkali using rice endosperm such as polished rice or rice flour as a raw material. When using polished rice, a part of protein is extracted by immersing it in an alkaline solution. When the soaked rice is pulverized by wet grinding or the like, the protein contained in the rice tissue is also extracted, so that the recovery rate can be increased. When using rice flour, protein is extracted with high efficiency by immersing it in an alkaline solution for 1 hour to 1 day.

The concentration of alkali used for extraction is preferably 0.1% to 2%, more preferably 0.15 to 0.25%. Since the protein solution to be extracted contains a large amount of alkali-soluble fiber, it is preferably removed using a sieve or a filter cloth having a fine mesh. By adjusting the pH to 5 to 6 by adding an acid such as hydrochloric acid to the protein solution, the aggregated protein can be recovered as a precipitate. If the protein solution is pre-heated to about 50 ° C and then neutralized, protein aggregates can be obtained even at pH 7, and if this is heated to 80 ° C or higher, the aggregates grow even larger. At least protein aggregates can be efficiently recovered by filtration using a sieve or filter press. A rice endosperm protein can be obtained by appropriately washing the recovered protein aggregate and drying it using airflow drying, fluidized bed drying, freeze drying, or the like. By heating at the time of neutralization, swollen protein aggregates are obtained. By drying the aggregates, rice endosperm proteins having superior water retention and touch compared to the case without heating can be obtained, and can be used for a wider range of applications. Can be used.

The rice endosperm protein in the present invention may be used alone as a serum uric acid lowering agent, disease risk reducing agent, monocyte chemotactic protein-1 expression reducing agent, or high-density lipoprotein cholesterol enhancer. Endosperm protein may be used as an active ingredient together with excipients and food materials. The processed food containing the rice endosperm protein composition can be used for beverages, baked goods, jelly-like foods, soups, porridges, and the like. In particular, it is preferable to use it for chewable tablets together with excipients, for baked confectionery, or for beverages / soups with starchy thickness, because rice endosperm protein can be processed with good texture.

In the present invention, it is desirable that the dose is appropriately determined in consideration of factors such as the patient's age, weight, symptoms, and the processed form of rice endosperm protein. Preferably, a daily intake of 0.5 to 20 g, more preferably 3 to 10 g of pure protein is good. When 3 to 10 g of pure protein is continuously ingested per day, it is expected that a serum uric acid level lowering effect appears in about 2 weeks to 6 months.

Food and pharmaceuticals (especially hyperuricemia, gout, gout) containing the serum uric acid lowering agent, disease risk reducing agent, monocyte chemotactic protein-1 expression reducing agent, or high-density lipoprotein cholesterol enhancing agent of the present invention When preparing one or more medicinal products for the treatment or prevention of kidney, cardiovascular, or cerebrovascular disorder), other ingredients that have uric acid production inhibitory effects or uric acid excretion promoting effects may be used together Also good. Although there is no restriction | limiting in particular in the component and mixing ratio used together, A sufficient quantity is desirable with respect to the effective amount of each component. The form of the drug is not particularly limited, but is preferably a form that can be administered orally.

Example 1 Preparation of Rice Endosperm Protein for Clinical Test and Test Food Production 25 kg of Koshihikari rice flour (purchased from Niigata Flour Milling Co., Ltd.) was suspended in 100 L of 0.2% sodium hydroxide solution and left overnight. The above suspension was supplied to a centrifuge “H-130I” manufactured by Kokusan Co., Ltd. at a flow rate of about 5 L / min. The rotation speed was 1,400 rpm. The centrifugal supernatant flowing out was collected and centrifuged again under the same conditions to obtain a protein extract from which the starch granules were removed. The extract was passed through a 285 mesh (aperture 53 μm) sieve to remove the fibrous material. This solution was heated to 50 ° C., and 6N hydrochloric acid was added to adjust the pH to 7.0. The solution was incubated at 80 ° C. for 30 minutes to grow a large protein aggregate. After cooling this, the protein was recovered on a sieve using a 285 mesh sieve. The protein was suspended in about 50 L of water and subjected to the same sieving treatment, and this operation was repeated three times to wash the protein with water. The obtained wet protein was squeezed into a squeezed bag to remove moisture, and then freeze-dried. The same operation was repeated 10 times to obtain about 7.5 kg of rice endosperm protein preparation.

<Example 2>
A test meal for clinical trials was produced using the rice endosperm protein preparation (see Table 1). The formulation was determined so that 1 g of the test food contained 5 g of rice endosperm protein as a pure protein.

A clinical trial was conducted to ingest rice endosperm protein in patients diagnosed with metabolic syndrome with the approval of the Ethics Committee. The clinical trial was a 4 week + 4 week crossover format. The subjects were divided into two groups and fed either a test meal containing rice endosperm protein or a control test meal in which rice endosperm protein was replaced with casein. After the completion of the test for the first 4 weeks, there was a 3 day suspension period, after which the test meal was replaced and the test continued for another 4 weeks. Table 1 shows the composition of each of the test meals containing rice endosperm protein and casein. Each 11 g of the test meal (5 g as a rice endosperm protein pure product) was filled in an aluminum wrapping material, and this was dissolved in water or hot water twice a day for drinking. Instructions were given to continue the normal diet during the test period, and the test meal was added to the foods normally consumed.

Subjects were those who met the following criteria.
(I) Selection criteria 1) Patients diagnosed with metabolic syndrome 2) Those who understand the purpose (including data use) and who have obtained document consent (II) Exclusion criteria 1) Serious in heart, kidney, liver, etc. 2) Severe infections, before and after surgery, severe trauma 3) Food allergies 4) Others who are inadequate for research participation by medical doctor

Twenty-four men diagnosed with metabolic syndrome became subjects, and the test was conducted in 12 groups divided into 2 groups. 18 subjects (9 in each group), excluding 6 excluded from the subjects, completed the study and were analyzed. The measured values at the start of the test (baseline) are shown in Table 2.

At the start of the test, blood was collected for a total of 3 times in the 4th and 8th weeks after the start of the test meal intake, and the values of serum uric acid level, lipid metabolism marker, and renal function marker were examined. As shown in Table 2, in the first half period (4 weeks) of the crossover test, a decrease in serum uric acid level (−0.40 mg / dL) was observed in the rice endosperm protein intake group. On the other hand, the serum uric acid level slightly increased (+0.17 mg / dL) in the casein intake group. When the amount of change in serum uric acid level after 4 weeks from the initial value was compared between the two groups, there was a significant difference at the 5% level on both sides. The average serum uric acid level of subjects who participated in this clinical study was 6.38 mg / dL, which is lower than the standard value for hyperuricemia of 7.0 mg / dL. Nonetheless, a tendency to decrease serum uric acid levels was suggested, suggesting that rice endosperm protein has a preventive effect as well as a curative effect on hyperuricemia.

Similarly, analysis of MCP-1 showed a slight decrease in the rice protein intake group, while a significant increase was observed in the casein intake group, and the change between groups was significant at the 5% level on both sides. Met. On the other hand, HDL-cholesterol showed an upward trend in the rice protein group, but showed a slight decrease in the casein group, and became significant at the 5% level in comparison between the groups. No significant changes were observed in the values of total cholesterol, LDL-cholesterol, and neutral fat in both groups.

Table 4 shows the results of the crossover analysis that included the latter half of the test. As in the first half, a significant decrease in uric acid, a decrease in MCP-1 levels, and a significant increase in HDL-cholesterol were observed due to rice protein intake.

<Example 3>
Under the approval of the Ethics Committee, a clinical trial was conducted to ingest rice endosperm protein in 9 maintenance dialysis patients (3 men and 6 women). Each subject drank the test meal (Example 2) containing rice endosperm protein in water or hot water once a day for 2 weeks. During the study period, instruction was given to continue the normal diet, and the test meal was added in addition to the food that was normally consumed.

As subjects, we recruited adult maintenance hemodialysis patients with a general condition and a tendency toward malnutrition. The criteria for selection are those with a serum albumin level of 3.8 mg / dl or less, a tendency toward malnutrition, and an understanding of the purpose of this clinical trial and written consent (gender-independent). did. Excludes persons with serious diseases in the heart, liver, etc., severe infections, before and after surgery, persons with severe trauma, persons with food allergies, and other persons judged inappropriate by the attending physician. did.

Serum uric acid levels were measured from blood collected at the start of the test and 2 weeks after the intake of rice endosperm protein. The results are shown in Table 5. In addition, since the 2nd test subject did not ingest the test meal for 5 days due to the common cold during the test period, the test subjects were excluded from the analysis target and analyzed by 9 subjects. When the mean value of serum uric acid at the second week after ingestion was compared with the value at the start, it decreased from 8.00 mg / dL to 7.09 mg / dL, and this difference was significant at the 5% level on both sides. .

Compared to Example 3, in this example, although the amount of rice endosperm protein intake and the intake period were both small, the decrease in the uric acid level was 0.91 mg / dL on average in this example. It was. This suggests that the effect of lowering the uric acid level of rice endosperm protein appears more prominently in cases where the uric acid level is high. Moreover, since the test subject is a maintenance dialysis patient, uric acid excretion by urine does not occur. Therefore, it was suggested that a mechanism other than the promotion of uric acid excretion into urine is acting on the serum uric acid level lowering effect of rice endosperm protein.

<Example 4>
Under the approval of the Ethics Committee, 8 test subjects with high serum uric acid levels (6.0 to 8.0 mg / dL) were given jelly-like test foods with the composition shown in Table 6 once a day. Ingested weekly. The test meals were taken daily after breakfast, and during the test period, they were instructed to limit excessive exercise, saving food and overeating that greatly deviated from the daily range. On the day before the test day, alcohol is prohibited, meals should be finished by 10:00 pm, and no food or drink will be instructed after that. On the day of the test day, after waking up, the test will be fasted until the end of the test. Yes), I visited the hospital in the morning and confirmed that I had fasted for more than 8 hours from the previous night, and then received an examination. Blood and urine were collected at the visit, and hematological tests, blood biochemical tests including uric acid, and urinalysis were performed.

As shown in Table 7, when 5 g of rice endosperm protein was ingested daily, the uric acid value decreased by 0.33 mg / dL on average. The decrease in uric acid level was more pronounced in people with higher uric acid levels prior to ingestion.

<Example 5>
Under the approval of the Ethics Committee, 13 test subjects with high serum uric acid levels (7.0-9.0 mg / dL) were given a powdery test food with the composition shown in Table 8 once a day. Ingested weekly. The test meals were taken daily after breakfast, and during the test period, they were instructed to limit excessive exercise, saving food and overeating that greatly deviated from the daily range. Also, the day before the test day, alcohol is prohibited, meals are finished by 10:00 pm, and after that, instructions are given not to eat or drink, and on the day of the test day, after waking up, fast until the end of the test (please water) I was allowed to come to the hospital in the morning, and after having confirmed that I had fasted for more than 8 hours from the previous night, I was tested. Blood and urine were collected at the visit, and hematological tests, blood biochemical tests including uric acid, and urinalysis were performed.

As shown in Table 9, when 5 g or more of rice endosperm protein was ingested daily, the uric acid level decreased by an average of 0.20 mg / dL at the 4th week and by an average of 0.22 mg / dL at the 8th week did. A decrease in uric acid level was more noticeable in people with higher uric acid levels before ingestion, and in people with higher urinary uric acid levels (creatinine correction values), a stratified analysis was performed. The results are shown in FIG. 1 and FIG. In the analysis of the top 6 blood uric acid levels, the uric acid level at 4 and 8 weeks was significantly lower than before intake, and the analysis of the top 7 urinary uric acid levels was 4 The blood uric acid levels at weeks and 8 weeks were significantly lower than those before ingestion.

These analysis results show that rice endosperm protein significantly lowers blood uric acid levels in people with high blood uric acid levels or those with high urinary uric acid levels corrected for creatinine by ingesting 5 g or more daily. .

Claims

Serum uric acid lowering agent containing rice endosperm protein as an active ingredient.
The serum uric acid lowering agent according to claim 1, wherein the rice endosperm protein is obtained by drying a protein extracted from an alkali from rice endosperm and then precipitated with an acid.
A pharmaceutical comprising the serum uric acid lowering agent according to claim 1 or 2.
A disease risk reducing agent that uses rice endosperm protein as an active ingredient, reduces the expression of monocyte chemotactic protein-1 induced by uric acid, and suppresses gout attacks, renal diseases, cardiovascular disorders, and cerebrovascular disorders.
5. The disease risk reducing agent according to claim 4, wherein the decrease in monocyte chemotactic protein-1 expression induced by uric acid is an action accompanying an increase in high density lipoprotein cholesterol.
Monocyte chemotactic protein-1 expression lowering agent containing rice endosperm protein as an active ingredient.
A high-density lipoprotein cholesterol enhancer containing rice endosperm protein as an active ingredient.