Patent Application
20100056560
The present invention relates to the use of a composition, containing isoflavone-containing soybean extract, L-carnitine, caffeine and arginine as active ingredients, for the treatment of obesity and diabetes.
In the human body, there are about 2×1010 fatty acids, which serve to store or release energy in the living mammalian body. Energy in these cells is stored and released according to complex regulatory mechanisms, and when the supply of energy is much larger than the demand, fatty acids are stored as neutral fats, and when energy is consumed, the neutral fats are decomposed into free fatty acids and glucoses. It is considered that obesity occurs when excessive energy is stored due to the unbalance of this process, and it is attributable to an increase in the size of fatty acids or in the number thereof.
Obesity occurring in 30-40% of modern persons is known to be a strong risk factor, which can cause hypertension, coronary artery diseases, type 2 diabetes and various forms of cancers. Particularly, obesity and diabetes are very closely connected with each other in the prevalent mechanisms.
Generally, obesity shows a decrease in insulin sensitivity with an increase in an increase in body fat, and particularly, the accumulation of abdominal fat is associated with glucose intolerance. Obesity is one of various causes of insulin resistance, and in some cases, type 2 diabetes do not occur in morbid obesity. However, in patients having type 2 diabetes, obesity and insulin resistance are closely correlated with each other, and thus, as obesity becomes severe, insulin resistance also becomes severe.
Dyslipidemia in type 2 diabetes is generally improved when blood glucose is regulated, but in some patients, it is not improved. The latter case is called “insulin resistance syndrome” or “central obesity syndrome”. The most important feature of the insulin resistance syndrome is central obesity or visceral obesity. The central obesity and the visceral obesity cause insulin resistance and accompany hyperinsulinemia, hypertension or impaired glucose tolerance.
The induction of diabetes by obesity is currently considered as an important issue, and insulin sensitivity-improving agents, which can reduce insulin resistance in order to improve obesity and diabetes simultaneously, have been reported. Examples of the insulin sensitivity-improving agents include Xenical (Orlistat) and Reductil (Sibutramine), as obesity treatment drugs, the therapeutic effects of which were proven through long-term clinical trials of thiazolidinedione drugs and biguanide drugs on obesity patients having metabolic syndromes. However, such drugs shows anti-obesity effects through the mechanism of appetite inhibiting appetite and fat absorption rather than promoting the burning and decomposition of fat, and thus are not sufficient for solving insulin resistance. For this reason, such drugs cannot completely solve diabetes together with obesity, and in addition, the serious side effects thereof have been reported, so that the safety thereof is not yet established. Accordingly, there is a need to develop a novel substance, which shows an effect equal to or higher than that of the prior substances and, at the same time, is safer.
Thus, in view of various diseases acting as causes of diabetes resulting from obesity, it is evident that a decrease in body weight is more important than a simple decrease in bodyweight. Accordingly, it seems to be preferable to find out a method capable of inhibiting the accumulation of ingested fat and activating the burning of the fat, and in this point of view, a method capable of maintaining the expression level of adiponectin secreted from adipocytes while increasing the beta-oxidation of fatty acids can be an excellent target for anti-obesity and anti-diabetic effects.
The applicant filed obesity-related patent applications relating to promoting the reduction of body fat. The patent applications disclose that genistein and carnitine increase the expression of a carnitine palmitoyltransferase-1 (CPT-1), which is a key enzyme in the tatty acid degradation pathway, so as to promote the burning of body fat (Korean Patent Application No. 2003-0018559), and that a composition, containing theanine, caffeine, genistein and carnitine alone or in a mixture, shows excellent effects on lipolysis and cellulite removal (Korean Patent Application No. 2003-0098859). However, it is not known whether such compositions can promote the burning of fat and increase the expression level of adiponectin so as to improve diabetes caused by obesity.
Accordingly, the present inventors have conducted many studies and experiments in order to solve the above-described problems occurring in the prior art and, as a result, have developed an ideal anti-obesity and anti-diabetic composition, which contains components acting to promote lipolysis and fat burning, without containing components having diuretic action or appetite-suppressing action, so that the composition can improve obesity by removing excessive body fat, particularly, abdominal fat, through lipolysis and fat burning, and, at the same time, can treat diabetes by lowering blood glucose levels through an increase in the expression of adiponectin gene, which regulates insulin sensitivity.
Therefore, it is an object of the present invention to provide a composition for treating obesity and diabetes, which is effective in improving obesity by promoting the decomposition and burning of fat, accumulated in adipocytes, to reduce body fat, and at the same time, is effective in treating and improving diabetes by overcoming insulin resistance.
To achieve the above object, the present invention provides the use of a composition, containing isoflavone and L-carnitine as active ingredients, for the treatment of diabetes.
Preferably, the composition further contains caffeine and arginine as active ingredients.
Hereinafter, the present invention will be described in further detail.
The composition according to the present invention shows the effects of preventing and treating obesity and diabetes not only by reducing body weight and body fat, but also by improving diabetic syndromes, which are typical metabolic syndromes which can be induced due to obesity.
Isoflavone, which is contained in soybean in large amounts and is a vegetable hormone similar to a female hormone, was reported to show various physiological activities. Recently, it was reported to have various effects, for example, the effects of regulating fat metabolisms in adipocytes and reducing blood cholesterol levels.
Carnitine, which is synthesized in the liver or kidneys of normal persons and contained in red fishes in large amounts, is known to be an important component in oxidizing fat to produce energy. When L-carnitine is deficient, the concentration of fatty acids in mitochondria is reduced, and thus the production of energy is also reduced. Also, CPT-1, which uses L-carnitine as a substrate, was found to act as an enzyme of reducing the rate of fatty acid oxidation, among various enzymes involved in fatty acid oxidation (Eaton, Prog Lipid Res 41(3): 197-269, 2002).
Caffeine, which is a methylxanthine material known as a positive control group of a lipolysis promoter, shows a lipolytic effect by increasing intracellular cAMP through the inhibition of phosphodiesterase closely associated with lipolysis in adipocytes (Astrup, A. et al., Am J. Clin. Nutr. 51:759, 1990).
Arginine is a natural L-amino acid, which is widely present in nature, and particularly, is contained in the sperm protein of fishes in a relatively large amount. It was reported that the intake of arginine stimulates the secretion of glucagon, which directly accelerates the decomposition of human adipose tissue (Kalkhoff R K, et al., N Engl J Med 289: 465-467). In fact, it was found that, when the blood glucagon concentration is high, the contents of free fatty acid and glycerol are increased.
The extraction of the active ingredients, which are used in the present invention, can be performed using a method suitably selected from among methods known in the art.
The skeletal muscle, which accounts for about 40% of the human body, is a major tissue that depends on the carbohydrate metabolism, and is also a major site that forms insulin resistance in obesity and type 2 diabetes (DeFronzo, 1992). Type 2 diabetes are characterized by abnormal insulin resistance and sugar metabolism in the skeletal muscle, and result in not only the interference of blood glucose maintenance, but also the disturbance of the fat metabolism due to an increase in circulating free fatty acid levels in blood (Reaven et al., 1988), a decrease in fat oxidation in the body (Kelly et al., 1999), and an increase in lipid deposition in various tissues, including the skeletal muscle (Pan et al., 1997).
Skeletal muscles and fatty acids contain glucose carrier Glut4. When the translocation of the glucose carrier (Glut4), which is regulated by insulin, into the cell surface, is stimulated, glucose is imported into cells. Insulin stimulates the translocation of Glut4 toward the cell membrane.
In type 2 diabetes, a defect in the translocation of Glut4 by insulin occurs, and this is also the characteristic of type 2 diabetes. The translocation of Glut4 can also be induced by other stimuli in addition to insulin, and such stimuli include exercise (contraction) (Lundet et al., 1995), hypoxia (Wojtaszewski et al., 1998), and various chemicals (Tsakiridis et al., 1995).
Adiponectin, which is one of typical adipokines secreted from fatty acids, was reported to have anti-obesity action, anti-diabetic action, anti-arteriosclerotic action, and an activity of inhibiting active oxygen production. Adiponectin functions to increase insulin sensitivity so as to lower blood glucose levels, thus preventing diabetes, and in addition, it acts on the liver and muscles to increase AMP kinase activity, so that it shows an anti-obesity effect of promoting fatty acid oxidation and inhibiting fat synthesis.
Adiponectin is a protein, the expression of which is increased with the differentiation of adipocytes, and it is regulated by transcription factors, such as PPAR-γ, C/EBP-α, SREBP1c, liver receptor homolog-1, Krupperl-like factor 7 (KLF7) and the like. In particular, KLF7 is a zinc finger protein reported to be very closely connected with type 2 diabetes. KLF7 is expressed in almost all tissues and is known to induce diabetes by inhibiting the differentiation of adipocytes, inhibiting the secretion of adiponectin and the like and inhibiting the secretion of insulin from pancreatic cells.
The composition according to the present invention is applied in the form of oral drugs and foods to decompose body fat and subcutaneous fat and, at the same time, to restore the expression of Glut4 and adiponectin, which are major bio-markers involved in insulin sensitivity, thus lowering blood glucose levels. This is because the composition of the present invention has the effects of promoting lipolysis and fat combustion and improving and maintaining insulin resistance, through different mechanisms in adipocytes.
In the present invention, the isoflavone is preferably an isoflavone-containing soybean extract, which is contained in an amount of 0.001-30 wt % based on the total weight of the composition.
Also, the composition according to the present invention preferably contains, based on the total weight of the composition, 0.0001-10 wt % of isoflavone and 0.001-40 wt % of L-carnitine.
Moreover, the composition of the present invention preferably contains, based on the total weight of the composition, 0.0001-10 wt % of caffeine and 0.001-40 wt % of arginine.
The contents of the components in the composition of the present invention were determined considering the synergistic effect of the components in the human body and the characteristic of each of the components in terms of safety. Also, the upper limits of the contents of the components were determined considering the molding conditions of a formulation comprising the components.
Accordingly, the present invention provides an oral composition for improving obesity and diabetes, which contains isoflavone, L-carnitine, caffeine and arginine, so that the composition promotes the decomposition of neutral fat in adipocytes, and inhibits the induction of insulin resistance through the promotion of lipolysis and fat burning to restore insulin sensitivity, thus inhibiting blood glucose elevation.
The composition of the present invention can be used as health foods, medical drugs and the like by suitably selecting, in addition to the above-described components, components conventionally used in the art, and then formulating the components in the form of tablets, capsules, soft capsules, pills, granules, drinks, diet bars, chocolates, caramels, confectioneries and the like.
As described above, the composition of the present invention contains isoflavone, carnitine, caffeine and arginine, so that it has the effects of promoting a process of decomposing neutral fat, accumulated in adipocytes, into free fatty acid and glycerol, and in addition, has the effect of promoting a process of burning fatty acid. Moreover, the inventive composition is effective not only in reducing body weight and body fat, but also in treating and improving type 2 diabetes by inhibiting the induction of insulin resistance by caffeine, which has a function of inhibiting the differentiation of adipocytes.
Hereinafter, the present invention will be described in further detail with reference to the following test examples. However, it will be obvious to those skilled in the art that these test examples are illustrative only, and the scope of the present invention is not limited thereto.
The epididymal adipose tissue of male KK mice was isolated, and then finely cut with scissors, and 0.1% collagenase (in DMEM without phenol red) was added thereto. Then, the tissue was cultured at 37° C. for 2 hours, and then filtered, thus obtaining adipocytes.
In order to examine the effect of the inventive composition on the lipid metabolism of obesity animals fed with a high fat diet, male KK mice were selected for use in the test. In order to examine the effect of a mixture of isoflavone-containing soybean extract, carnitine, arginine and caffeine (hereinafter, referred to as “ICAC”), 6-week-old mice were acclimated for one week and fed with a high-calorie diet for 3 weeks. Then, the mice were randomly grouped into four test groups, each consisting of 12 animals. The test groups were as follows: (1) a normal-fat diet group; (2) a group fed with normal diet+20 mg isoflavone+150 mg L-carnitine; (3) a group fed with normal diet+600 mg arginine+25 mg caffeine; and (4) a group fed with normal diet+20 mg isoflavone+150 mg L-carnitine+600 mg arginine+25 mg caffeine. The test groups were fed with the test diets for 2 weeks. Herein, the test diets were prepared to have a total calorie of 3.1 kcal/g, because the total calorie of the high-calorie diet was 4.7 kcal/g as shown in Table 1 below.
During the feeding period of the test diets, the diet intake and body weight of the mice were measured three times each week. After completion of the feeding of the test diets, the body weight of the mice was finally measured, and the measurement results of a change in body weight, caused by the test diets, are shown in Table 2 below.
As can be seen in Table 2 above, before the start of the test, there was no difference in body weight between the test groups. However, during the test period, the group fed with isoflavone+L-carnitine and the group fed with L-arginine+caffeine showed increases in body weight of 5.3% and 5.6%, which were significantly lower than 12.8% for the normal diet group. Also, the group fed with isoflavone+L-carnitine+L-arginine+caffeine showed an increase in body weight of −3.0%, which was significantly lower than that of the normal diet group, suggesting that there was a synergistic effect between the components of the mixture. In addition, there was no significant difference in diet intake between the test groups.
In order to examine the effect of the inventive composition on the lipid metabolism of obesity animals fed with a high fat diet, male KK mice was selected as test models and grouped into four groups: a normal diet group; a group fed with normal diet+isoflavone+L-carnitine; normal diet+L-arginine+caffeine; normal diet+isoflavone+L-carnitine+L-arginine+caffeine. The test diets were fed to the test animals at the same concentrations as in Example 1 for 2 weeks. After completion of diet feeding, the animals were sacrificed, and 2 ml of blood was sampled from the mice using an orbital blood sampling method. The blood sample was centrifuged at 10000 rpm for 10 minutes, and the supernatant (plasma) was isolated and analyzed for plasma glucose, triglyceride and total cholesterol levels using an automatic blood analyzer (H1 system, Technicon, USA). In the glucose and total cholesterol levels, the group fed with isoflavone+L-carnitine and the group fed with L-arginine+caffeine showed no significant decrease compared to the normal diet group, but the group fed with isoflavone+L-carnitine+L-arginine+caffeine showed a significant decrease compared to the normal diet group. In the triglyceride level, the group fed with isoflavone+L-carnitine and the group fed with L-arginine+caffeine showed a significant decrease compared to the normal diet group, and the group fed with isoflavone+L-carnitine+L-arginine+caffeine showed a decrease of 34% compared to the normal diet group. These results are shown in Table 1 below. In
In order to examine the effect of the inventive composition on the lipid metabolism of obesity animals fed with a high fat diet, male KK mice was selected as test models and grouped into four groups: a normal diet group; a group fed with normal diet+isoflavone+L-carnitine; normal diet+L-arginine+caffeine; normal diet+isoflavone+L-carnitine+L-arginine+caffeine. The test diets were fed to the test animals at the same concentrations as in Example 1 for 2 weeks. After completion of diet feeding, the animals were sacrificed, and the liver, subcutaneous fat, epididymal adipose, peritoneal and retroperitoneal adipose and mesenteric adipose were resected from the animals. The resected tissues were washed with physiological saline and placed on filter paper so as to remove water. Then, the weights of the tissues measured, and the measurement results are shown in Table 3 below.
During the test period, the group fed with isoflavone+L-carnitine and the group fed with L-arginine+caffeine did not show a great decrease in the weight of adipose tissues compared to the normal diet group, but the group fed with isoflavone+L-carnitine+L-arginine+caffeine showed a statistically significant decrease in the weight of adipose tissues compared to the normal diet group. Thus, it was observed that isoflavone, L-carnitine, L-arginine and caffeine showed a synergistic effect on a reduction in body fat in the mice fed with high-calorie diet.
20-week-old male KK mice were fed with normal diet, normal diet+2 mg isoflavone+15 mg L-carnitine, normal diet+60 mg L-arginine+2.5 mg caffeine, and normal diet+2 mg isoflavone+15 mg L-carnitine+60 mg L-arginine+2.5 mg caffeine, and after 60 minutes, the animals were fed with 50 μg/100 g b.w. of epinephrine in order to induce lipolysis. At 120 minutes after the feeding of the diets, plasma was collected from the animals of the four test groups according to the method of Test Example 2, and tests for evaluating the effects of the diets on the promotion of decomposition of neutral fat in the adipocytes of the KK mice were performed using the collected plasma. The lipolysis effects were determined by measuring the concentration of glycerol released from the adipocytes into the plasma. The quantification of glycerol was performed using a GPO-trinder kit (Sigma, St. Louis, Mo., U.S.A), and the absorbance was measured at 540 nm using an ELISA reader.
In the results of glycerol quantification, as shown in
In order to evaluate the promotion of decomposition of neutral fat in the adipocytes of KK mice according to the same method as in Test Example 4, clamps were placed around the artery and vein of the muscle tissue of the mice, and at 0 min, 60 min and 90 min from 120 minutes after the diet feeding, 200 ml of blood was sampled from each of the test groups using a syringe (Sarstedt, Leicester, United Kingdom). Plasma was isolated from each of the blood sample. The effects of the test diets on fatty acid oxidation were determined by calculating non-esterified fatty acid (NEFA) uptake. The NEFA amount was quantified using a Wako NEFA C kit (Wako Chemicals Inc., Richmond, Va.), the absorbance was measured at 550 nm using an ELISA reader, and the NEFA uptake was calculated from the difference between the imported NEFA amount and the released NEFA amount.
In the results of quantification of NEFA uptake (non-esterified fatty acid uptake), as shown in
Step 1: Adipocyte Cell Line and Cell Differentiation
Mouse undifferentiated 3T3-L1 adipocytes) (purchased from ATCC) were cultured in 10% calf serum-containing DMEM (Dulbecco's modified Eagle's medium, Gibco 1210-0038) in a 10% CO2 incubator to a confluency of 70% while replacing the medium with a fresh medium at 2-day intervals. For differentiation into adipocytes, the cells were cultured in a medium (containing 10% fetal bovine serum, 0.5 mM 3-isobutyl-1-methyxanthine (Sigma), 1 μM dexamethasone (Sigma) and 167 nM insulin (Novo-Nordisk)) for 48 hours, and then the medium was replaced with a DMEM medium (containing 10% fetal bovine serum and 167 nM insulin), in which the cells were further cultured for 48 hours. Finally, the cells were further cultured in a medium (containing only 10% fetal bovine serum) for 48 hours, thus obtaining differentiated adipocytes.
Step 2: Effect of Treatment with Isoflavone, L-Carnitine, Caffeine and Arginine on Inhibition of 3T3-L1 Adipocyte Differentiation
The adipocytes, differentiated in the step 1, were cultured in a medium, containing 5% fatty acid-free calf serum, for 16 hours. On the next day, the cells were washed three times with PBS, and then treated with each of 1 μM isoflavone, 1 mM L-carnitine, 1 mM L-arginine, 10 ppm caffeine and a mixture of 1 μM isoflavone+1 mM+1 mM L-arginine+10 ppm caffeine. The cells were treated with each of the test materials together with the replacement of medium at 48-hr intervals, and after 8 days, the amount of neutral fat in the cells was measured through Sudan II staining. The measurement results are shown in
As can be seen in
Step 1: Adipocyte Cell Line and Cell Differentiation
This step was conducted in the same manner as in the step 1 of Test Example 6.
Step 2: Effect of Treatment with Isoflavone, L-Carnitine, Caffeine and Arginine on Promotion of Lipolysis in 3T3-L1 Adipocytes
The adipocytes, differentiated in the step 1, were cultured in a medium, containing 5% fatty acid-free calf serum, for 8 days. Then, the differentiated adipocytes were washed three times with PBS, and then treated with each of 10 μM isoflavone, 0.5 mM L-carnitine, 1 mM L-arginine, 10 ppm caffeine and a mixture of 10 μM isoflavone 0.5 mM L-carnitine+1 mM arginine+10 ppm caffeine for 6 hours. Then, the medium was collected, and the concentration of glycerol in the medium was measured using a GPO-Trinder kit (Sigma diagnostics, St. Louis, Mo.). The measurement results are shown in
As can be seen in
Step 1: Adipocyte Cell Line and Cell Differentiation
This step was performed in the same manner as in the step 1 of Test Example 6
Step 2: Effect of Treatment with Mixture of Isoflavone, L-Carnitine, Caffeine and Arginine on Increase in Expression of Adiponectin in 3T3-L1 Adipocytes
The adipocytes, differentiated in the step 1, were cultured in a medium, containing 51 fatty acid-free calf serum, for 16 hours. On the next day, the cultured cells were washed three times with PBS, and then treated with each of 100 μM isoflavone, 1 mM L-carnitine, 1 mM L-arginine, 100 ppm caffeine and a mixture of 100 μM isoflavone+1 mM L-carnitine+1 mM L-arginine+100 ppm caffeine. After 24 hours of cell incubation, a protein was isolated from each of the media and subjected to Western blot analysis in order to examine a change in the expression of adiponectin. The analysis results are shown in
This effect is believed to be because the four components were used in a mixture. That is, it was found that, when adipocytes were treated with the mixture of the four components, and the accumulation of fat in the adipocytes was inhibited, the consumption of energy in other tissues was continuously promoted. Thus, the use of the four components in a mixture is effective in improving type 2 diabetes caused by insulin resistance, which can occur when a substance having the same mechanism as that of caffeine is used alone.
Step 1: Adipocyte Cell Line and Cell Differentiation
This step was performed in the same manner as in the step 1 of Test Example 6
The adipocytes, differentiated in the step 1, were cultured in a medium, containing 5% fatty acid-free calf serum, for 16 hours. On the next day, the cultured cells were washed three times with PBS, and then treated with each of 100 μM isoflavone, 1 mM L-carnitine, 1 mM L-arginine, 100 ppm caffeine and a mixture of 100 μM isoflavone+1 mM L-carnitine+1 mM L-arginine+100 ppm caffeine. After 24 hours of cell incubation, a protein was isolated from each of the media and subjected to Western blot analysis in order to examine a change in the expression of Glut4. The analysis results are shown in
As can be seen in
As described above, the inventive composition for the improvement of obesity and diabetes is effective not only in reducing body weight and body fat, but also in treating and improving type 2 diabetes. Accordingly, it is very useful in the food and drug industries.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2006-0106362 | Oct 2006 | KR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/KR07/04160 | 8/29/2007 | WO | 00 | 6/18/2009 |
