JP7595271B2 - Composition for suppressing increase in blood PCSK9 concentration - Google Patents

Description

The present invention relates to a composition for suppressing an increase in blood PCSK9 concentration.

In recent years, the number of patients developing dyslipidemia (hypercholesterolemia, hyperlipidemia) and resulting arteriosclerosis due to obesity caused by a shift to a high-calorie, high-cholesterol diet and poor lifestyle habits has been increasing rapidly, making it urgent to take measures.

Currently, HMG-CoA reductase inhibitors (statins) are approved as one of the treatments for hypercholesterolemia. However, although statins strongly lower LDL (low-density lipoprotein) cholesterol, the side effect of statins is that they increase the risk of rhabdomyolysis, which means that they cannot be administered in high doses. Therefore, there has been a demand for the development of a drug that has a different mechanism of action from statins and can lower LDL cholesterol.

On the other hand, PCSK9 (Proprotein Convertase Subtilisin/Kexin type 9), which regulates the metabolism of LDL receptors by binding to them and breaking them down, has recently been attracting attention. Although the role of PCSK9 in the body is still unclear, the effect of reducing blood LDL cholesterol by suppressing the expression of PCSK9 has been clarified. Blood LDL cholesterol is taken up into cells by the LDL receptors present on the cell surface, but when PCSK9 is overexpressed, the degradation of the LDL receptors progresses and the receptors become insufficient. As a result, the uptake of blood LDL cholesterol into cells becomes insufficient, and as a result, blood LDL cholesterol increases, increasing the risk of arteriosclerosis and other diseases.

Currently, therefore, development of pharmaceuticals that inhibit the activity of PCSK9 in the blood or suppress the expression of PCSK9 is underway. For example, Patent Document 1 discloses fully human monoclonal antibodies (mAbs) that specifically bind to human PCSK9 (hPCSK9) and antigen-binding fragments thereof, and Patent Document 2 discloses antisense nucleotides that target PCSK9 mRNA and conjugates thereof.

However, although these antibody and nucleic acid drugs are highly specific and effective, they currently have low productivity and are expensive, which means that they impose a large economic burden on patients who require long-term treatment, and some patients may experience side effects.

Special Publication No. 2012-511913 Special Publication No. 2016-523094

Therefore, the object of the present invention is to provide a composition or agent for suppressing an increase in blood PCSK9 concentration that is inexpensive and has few side effects.

After extensive research into PCSK9, the inventors unexpectedly discovered that continuous intake of D-psicose can suppress increases in blood PCSK9 concentrations.

That is, the present invention has been completed based on the above findings, and comprises the following [1] to [7].
[1] A composition for suppressing an increase in blood PCSK9 concentration, comprising D-psicose as an active ingredient.
[2] The composition according to the above-mentioned [1], for allowing the intake of 0.1 g to 0.5 g of D-psicose per kg of body weight per day.
[3] The composition according to the above-mentioned [1], for continuously ingesting 0.1 g to 0.5 g of D-psicose per kg of body weight per day for at least 28 days.
[4] An agent for suppressing an increase in blood PCSK9 concentration, comprising D-psicose as an active ingredient.
[5] The agent according to the above-mentioned [4], for allowing the intake of 0.1 g to 0.5 g of D-psicose per kg of body weight per day.
[6] The agent according to the above-mentioned [4], for continuously ingesting D-psicose at a rate of 0.1 g to 0.5 g per kg of body weight per day for at least 28 days.
[7] A method for suppressing an increase in blood levels of PCSK9, comprising administering 0.1 g to 0.5 g of D-psicose per kg of body weight per day for at least 28 consecutive days.

By ingesting the composition for suppressing an increase in blood PCSK9 concentration, which contains D-psicose as an active ingredient, the increase in blood PCSK9 concentration can be suppressed.

FIG. 1 is a diagram showing the procedure of a test (Example 3) on the first and last days of continuous ingestion of a sample (15 g of D-psicose). FIG. 1 shows the average blood PCSK9 concentrations of all subjects (14 subjects) whose blood was drawn on the first and last days of continuous sample intake (Example 3).

In the present invention, "inhibition of increase" of blood PCSK9 concentration means that the blood PCSK9 concentration does not increase relatively after ingestion of a sample. Specifically, the blood PCSK9 concentration of each subject is measured by taking a sample for a certain period of time and blood samples are taken before and after ingestion of the sample using a commercially available kit (e.g., "CircuLex Human PCSK9 ELISA Kit" or "CircuLex Mouse/Rat PCSK9 ELISA Kit" manufactured by CircuLex Corporation), and the blood PCSK9 concentration after ingestion of the sample does not increase compared to the blood PCSK9 concentration before ingestion of the sample.

The D-psicose in the present invention is most simply produced by using an enzyme (epimerase) from D-fructose as a raw material, but it is not limited to being produced enzymatically, and may also be produced chemically.

The daily intake of D-psicose, the active ingredient of the present invention, must be at least 0.05 g/kg body weight, preferably 0.1 g to 0.5 g/kg body weight, more preferably 0.2 to 0.5 g/kg body weight, and even more preferably 0.2 to 0.4 g/kg body weight. The composition or agent of the present invention is preferably designed to allow intake of this dose.

The intake period of the composition for suppressing an increase in blood PCSK9 concentration in the present invention is at least 14 days, preferably 28 days, and more preferably 56 days.

The method of ingestion of the composition or agent for suppressing an increase in blood PCSK9 concentration in the present invention is not particularly limited, but for example, it can be taken orally in the form of an aqueous solution, tablet, granule, etc., and if it is an aqueous solution, it can also be administered by subcutaneous injection. The timing of ingestion may be before, during, or after a meal, but before or during a meal is preferable, and before a meal is more preferable.

The composition or agent for suppressing an increase in blood PCSK9 concentration in the present invention can also be incorporated into food and beverages. Examples of the composition or agent include, but are not limited to, bakery foods, noodles, snack foods such as okonomiyaki, takoyaki, and pancakes, Japanese sweets, fish pastes, batter for fried foods, fritters, yogurt, puddings, jellies, dressings including mayonnaise and sauces, thickened sauces, frozen desserts such as ice cream, meat products, cooked rice, powdered drinks, soft drinks, carbonated drinks, and various drinks such as jellies.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

<Continuous D-psicose intake test in hamsters>
The effect of D-psicose intake on the PCSK9 concentration in the blood of hamsters was confirmed. The experimental animals were 16 male Golden Syrian hamsters (hereinafter referred to as hamsters) aged 5 weeks and 16 hamsters aged 4 weeks. First, 16 hamsters aged 5 weeks were pre-bred for 1 week, and then divided into two groups (8 animals per group), a control intake group and a 3% D-psicose intake group, and bred for 8 weeks with free intake of normal experimental feed (hereinafter referred to as normal diet) according to the composition of Table 1 and water. Then, blood was collected from each hamster. Next, 16 hamsters aged 4 weeks were pre-bred for 1 week, and then free intake of high-fat experimental feed (hereinafter referred to as high-fat diet) according to the composition of Table 1 and water was induced for 4 weeks to induce obesity.

After inducing obesity, the hamsters were divided into two groups (8 animals per group), a control group and a 3% D-psicose group, and were kept with free access to a high-fat diet and water for four weeks. Blood was then collected from each hamster.

<Measurement and results of PCSK9 concentration in hamster blood>
The PCSK9 concentration in the blood of the above-mentioned hamsters (32 animals) was measured using a commercially available kit (CircuLex Mouse / Rat PCSK9 ELISA Kit manufactured by Cyclex). The average value of the blood PCSK9 concentration of each individual by group is shown in Table 2.

As a result, the group that ingested 3% D-psicose on a normal diet had a significantly reduced blood PCSK9 concentration compared to the control group (Example 1). The group that ingested 3% D-psicose on a high-fat diet also had a significantly reduced blood PCSK9 concentration compared to the control group (Example 2).

The hamsters ingested an average of 205 kcal/kg of body weight of food per day, which was calculated to be about 6.1 times the daily energy intake of a human (body weight 60 kg). The hamsters ingested an average of 1.5 g/kg of body weight of D-psicose per day, which is six times the amount (0.25 g/kg of body weight) of a human (body weight 60 kg) ingesting 15 g of D-psicose per day. Therefore, the amount of D-psicose ingested by the hamsters was equivalent to that of a human (body weight 60 kg) ingesting 15 g of D-psicose per day.

<Continuous D-psicose intake test in humans>
Next, the effect of continuous intake of D-psicose on the PCSK9 concentration in human blood was confirmed. The subjects were men aged 20 years or older and younger than 70 years old, and were untreated hypercholesterolemia (120 mg/dl≦fasting LDL-C<160 mg/dl: 7 subjects) and untreated borderline diabetes mellitus with expected elevated LDL cholesterol levels (110 mg/dl≦fasting blood glucose level<126 mg/dl, or 6.2<HbA1c (NGSP)<6.5: 7 subjects).

The total intake period was 56 days, and for the 54 days excluding the first and last days of intake, participants were asked to take 15 g of the sample D-psicose together with water or other liquids once a day within one hour before any meal.

The following test was conducted at the test facility for the first and last two days of taking 15 g of D-psicose (Figure 1). After the subjects were examined by a doctor at the test facility one hour before the start of the test, they took 15 g of D-psicose (the time when the ingestion started was the start of the test), and blood was collected from each subject every two hours from just before the start of the test until 10 hours after. Immediately after taking 15 g of D-psicose, the designated breakfast was taken with 150 ml of water over a 15-minute period, and 4 hours after the start of the test, the designated lunch was taken, and 8 hours after the start of the test, the designated dinner was taken with 150 ml of water over a 15-minute period. In addition, 6 hours after the start of the test, 150 ml of water was taken. The collected blood from each subject was used to measure PCSK9.

<Measurement and results of PCSK9 concentration in human blood>
The blood PCSK9 concentration of all the above subjects (14 people) was measured using a commercially available kit (CircuLex Human PCSK9 ELISA Kit manufactured by Cyclex). The average value and standard deviation of the blood PCSK9 concentration of each individual for all subjects are shown in Table 3 and FIG.

As a result, the PCSK9 concentration in blood drawn immediately before the start of the test on the final day was lower than the same time period on the first day (Figure 2: 0 hr). In addition, the PCSK9 concentration in blood 2 and 4 hours after the start of the test on the final day was significantly lower than the same time period on the first day (Figure 2: 2-4 hr). Furthermore, the PCSK9 concentration in blood 6-10 hours after the start of the test on the final day was even more significantly lower than the same time period on the first day (Figure 2: 6-10 hr).

As described above, since the increase in blood PCSK9 concentration is suppressed by taking D-psicose, it is possible to provide a composition for suppressing the increase in blood PCSK9 concentration that contains D-psicose as an active ingredient, and it is expected that the intake of such a composition will reduce LDL cholesterol in the blood.

Claims (6)

A composition for suppressing increases in blood PCSK9 levels that contains D-psicose as an active ingredient. The composition according to claim 1, for ingesting 0.1 g to 0.5 g of D-psicose per kg of body weight per day. The composition according to claim 1, for allowing a subject to continuously ingest 0.1 g to 0.5 g of D-psicose per kg of body weight per day for at least 28 days. An inhibitor of elevated blood PCSK9 levels, with D-psicose as the active ingredient. The agent according to claim 4, for allowing a subject to take 0.1 g to 0.5 g of D-psicose per kg of body weight per day. The agent according to claim 4, for allowing a subject to continuously ingest 0.1 g to 0.5 g of D-psicose per kg of body weight per day for at least 28 days.

Images