[go: up one dir, main page]

WO2008068762A2 - Formulation de chitosan pour la réduction du cholestérol chez les hommes - Google Patents

Formulation de chitosan pour la réduction du cholestérol chez les hommes Download PDF

Info

Publication number
WO2008068762A2
WO2008068762A2 PCT/IL2007/001512 IL2007001512W WO2008068762A2 WO 2008068762 A2 WO2008068762 A2 WO 2008068762A2 IL 2007001512 W IL2007001512 W IL 2007001512W WO 2008068762 A2 WO2008068762 A2 WO 2008068762A2
Authority
WO
WIPO (PCT)
Prior art keywords
formulation
chitosan
particles
acid
cholesterol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IL2007/001512
Other languages
English (en)
Other versions
WO2008068762A3 (fr
Inventor
Noah Ben-Shalom
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of WO2008068762A2 publication Critical patent/WO2008068762A2/fr
Anticipated expiration legal-status Critical
Publication of WO2008068762A3 publication Critical patent/WO2008068762A3/fr
Ceased legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
    • A61K31/715—Polysaccharides, i.e. having more than five saccharide radicals attached to each other by glycosidic linkages; Derivatives thereof, e.g. ethers, esters
    • A61K31/716—Glucans
    • A61K31/722—Chitin, chitosan
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/66—Phosphorus compounds
    • A61K31/683—Diesters of a phosphorus acid with two hydroxy compounds, e.g. phosphatidylinositols
    • A61K31/685—Diesters of a phosphorus acid with two hydroxy compounds, e.g. phosphatidylinositols one of the hydroxy compounds having nitrogen atoms, e.g. phosphatidylserine, lecithin
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/14—Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
    • A61K9/16—Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
    • A61K9/1605—Excipients; Inactive ingredients
    • A61K9/1617—Organic compounds, e.g. phospholipids, fats
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/14—Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
    • A61K9/16—Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
    • A61K9/1682—Processes
    • A61K9/1694—Processes resulting in granules or microspheres of the matrix type containing more than 5% of excipient
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/20—Pills, tablets, discs, rods
    • A61K9/2004—Excipients; Inactive ingredients
    • A61K9/2022—Organic macromolecular compounds
    • A61K9/205—Polysaccharides, e.g. alginate, gums; Cyclodextrin
    • A61K9/2054—Cellulose; Cellulose derivatives, e.g. hydroxypropyl methylcellulose

Definitions

  • the present invention relates to the field of cholesterol-reducing formulations. More particularly, the present invention relates to a cholesterol-reducing formulation comprising hydrophobic microparticles of a positively charged polymer such as chitosan and an anionic or non-ionic surfactant, such as lecithin, methods of preparation and uses thereof.
  • a positively charged polymer such as chitosan
  • an anionic or non-ionic surfactant such as lecithin
  • Cholesterol is a sterol lipid found in the bloodstream and in the cell membranes of all body tissues.
  • the structure of cholesterol is as follows:
  • Cholesterol is composed of three regions: a hydrocarbon tail; a ring structure region with 4 hydrocarbon rings; and a hydroxyl group.
  • the hydroxyl group is polar, which makes it soluble in water.
  • the ring region and tail region are non-polar, so are soluble in organic solvents, but insoluble in water.
  • LDL Low-density lipoprotein
  • High-density lipoprotein (HDL) is known as “good” cholesterol.
  • Aa elevated LDL blood cholesterol level may lead to slow build up of cholesterol deposits in the walls of the arteries feeding the heart and brain, forming a plaque which can clog these arteries, a condition known as artherosclerosis.
  • a clot thrombus that forms near this plaque can block the blood flow to part of the heart muscle and cause a heart attack. If such a clot blocks the blood flow to part of the brain, a stroke results.
  • a high level of LDL cholesterol 160 mg/dL and above) reflects an increased risk of heart disease.
  • Chitosan is the only naturally occurring, positively charged polysaccharide, and is generally produced by deacetylation of chitin, a naturally occurring biopolymer, found in the cytoskeleton and hard shells of marine organisms such as Crustacea, shrimps, crabs, fungi, etc.
  • Chitosan is biocompatible, non-toxic, and non-immunogenic, allowing its use in the medical, pharmaceutical, and cosmetic fields.
  • the soluble form of chitosan contains positively charged amino groups that are able to form ionic bonds with anionic compounds, including proteins and fatty acids.
  • chitosan may form hydrophobic bonds.
  • chitosan In order to use chitosan in aqueous solution, dissolution of the crystalline structure must take place. In hydrated crystalline chitosan, water molecules form columns between chitosan sheets and contribute to stabilizing the structure by making water-bridges between polymer chains. The hydrogen bonds are broken during the dissolution process of the chitosan using weak organic acids like acetic acid.
  • the mechanism of dissolution of polyelectrolyte powders is believed to involve the formation of a spherical grain structure. In pure water, this includes the rapid formation of a gel layer around the particle, followed by the slow release of polymer chains into the solvent. The slow process of polymeric chains leaving an aggregate was explained as being due to the effect of an attractive potential forming between the charged individual polymer and the electroneutral aggregate. It is known that equilibration times for the dissolution of polyelectrolytes are often in the order of hours and even many days (Michel, RC et al. Biopolymers 53: 19- 39, 2000; Reed WF et al. Ber Bunzen Phys Chem 100: 685-695, 1996). The duration time of stirring of the chitosan solution is reported to be 12-24 h at room temperature Fredheim GE et al Biomacromolecules 4:232-239, 2003.
  • chitosan is able to absorb blood cholesterol in small animals (particularly mice and rats), as well as bile lipids, thereby lowering the blood levels of these molecules [J. Nutr. 2000; 130: 2753-2759 ⁇ A number of studies have shown that chitosan has the unique ability to lower levels of "bad” LDL cholesterol, while boosting "good” HDL cholesterol levels.
  • Cholesterol is a precursor of bile acids, which are steroid acids found mainly in the bile of mammals, having both a hydrophilic and a hydrophobic face. It has been suggested that chitosan reduces blood cholesterol by absorption of bile acids, causing increased use of cholesterol in further synthesis of bile acids, thereby removing cholesterol from the blood.
  • a food fiber supplement comprising chitosan and glucomannan has been shown to lower blood cholesterol in rats [J Nutr. 2000; 130: 2753-2759] and in humans [J. Am. College Nutrition 2002; 21(5): 428-433].
  • large amounts of the fiber supplement were required in order to produce the cholesterol-lowering effect in humans, requiring the ingestion of fifteen capsules per day, providing 1.2 g/day each of chitosan and glucomannan.
  • the total serum cholesterol in the human study was lowered by only about 7%, and the LDL cholesterol by 10%.
  • U.S Patent Nos. 7,067,146 and 6,814,975; U.S. Patent Application No. 20050079204; and European Patent No. 1233682 to Eritocap teach use of chitosan together with eritadenine in the preparation of a foodstuff for reduction of cholesterol.
  • U.S. Patent No. 6,323,189 and European Patent No. 1100344 teach a stable chitosan-containing liquid suspension for weight treatment.
  • U.S. Patent Application. No. 20050175763 teaches a phospholipd-containing stable matrix consisting of a supporting material in the form of a carbohydrate, such as chitosan.
  • U.S. Patent Application No. 20050100619 teaches a cholesterol-lowering supplement which may include chitosan and a phospholipid, together with a further composition capable of inhibiting cholesterol biosynthesis and a composition capable of increasing cholesterol metabolism.
  • Chitosan is unable to reduce cholesterol in the stomach, since it cannot absorb non-emulsified fats in the absence of bile salts, which are secreted only in the small intestine.
  • chitosan dissolves and becomes positively charged in the acid conditions of the stomach, due to its functional amino groups.
  • the highly charged polymer can react strongly with negatively-charged materials, such as phospholipids, which are present in the stomach, and become partially saturated. As a result, the amount of ingested chitosan having positively-charged groups available for interaction with the negatively charged bile acids after passing through the stomach is decreased. There is thus a widely recognized need for, and it would be highly advantageous to have an improved formulation comprising chitosan which provides delivery of an increased proportion of unsaturated chitosan to the small intestine, for reducing blood cholesterol in humans.
  • the present invention provides formulations for reduction of cholesterol in humans, the formulation comprising chitosan and an anionic or non-ionic surfactant, methods of preparation and uses thereof.
  • a formulation for the reduction of cholesterol in humans comprising composite, hydrophobic particles of chitosan and an anionic or non-ionic surfactant.
  • a method of producing a formulation for the reduction of cholesterol in humans comprising preparing a first solution comprising chitosan by mixing with an acid for at least 24 hours; preparing a second solution comprising an anionic or non- ionic surfactant; mixing the first and second solutions in acid conditions to form composite particles; and preparing a powder of the composite particles.
  • the first solution is prepared in an acid selected from the group consisting of hydrochloric acid or an organic acid.
  • the organic acid is selected from the group consisting of lactic acid and glutamic acid.
  • the second solution is prepared in water.
  • the chitosan concentration in the first solution may comprise, for example, about 0.7%.
  • the pH of the solution is preferably adjusted to a value of about 3.5.
  • the method may optionally further comprise the step of adjusting the pH of the suspension medium, after removal of said particles, to a value of about 7.
  • the suspension medium may optionally be allowed to stand for about 30 minutes, then filtered to remove the particles. Further optionally, the removed particles may be resuspended in acid medium.
  • the powder may be prepared, for example, by spray drying or lyophlization.
  • mixing of the first and second solutions is carried out at a temperature of 25° for a time of no greater than 15 minutes.
  • a method for increasing cholesterol reduction in humans by chitosan comprising increasing the hydophobicity of said chitosan.
  • the hydrophobicity is increased by reacting chitosan with an anionic or non-ionic surfactant.
  • a method for the reduction of cholesterol in a human subject comprising administering to the subject a formulation comprising composite, hydrophobic particles of chitosan and an anionic or non-ionic surfactant.
  • the composite, hydrophobic particles may comprise microparticles.
  • a formulation for the reduction of cholesterol in humans comprising composite, hydrophobic microparticles comprising a cationic polymer and an anionic or non-ionic surfactant.
  • the cationic polymer comprises chitosan.
  • the anionic surfactant is preferably selected from the group consisting of phospholipids; bile salts; sodium lauryl ether sulfate; citric acid esters of monoglycerides; sodium, calcium or acid stearoyl lactylate; stearyl citrate; fatty acids or salts thereof; diacetyl tartaric acid esters of monoglycerides; or combinations thereof. More preferably, the phospholipids comprises lecithin.
  • the non-ionic surfactant is a fatty alcohol.
  • the chitosan has a degree of acetylation of from about 70% to about 95%.
  • the chitosan comprises high molecular weight chitosan having a molecular weight in the range of from about 5x10 5 to about 3x10 6 daltons,.
  • a ratio of surfactant: chitosan is optionally and preferably in the range of from about 0.2:1 to about 5:1. More preferably, the ratio is in the range of from about 3:1 to about 4:1.
  • a concentration of chitosan is preferably about 0.7% w/w. More preferably, the concentration is in the range of from about 0.7% w/w to about 3.5% w/w.
  • the chitosan and the surfactant in the composite particles are connected by ionic and hydrophobic interactions
  • the formulation may optionally further comprise a cholesterol-reducing agent selected from the group consisting of a statin, a fibrate, niacin, a bile acid sequestrant, ezetimibe, or a phytosterol, or combinations thereof.
  • a cholesterol-reducing agent selected from the group consisting of a statin, a fibrate, niacin, a bile acid sequestrant, ezetimibe, or a phytosterol, or combinations thereof.
  • the formulation may optionally further comprise an enteric coating layer.
  • the formulation or method of the present invention may be used in the treatment or prevention of a condition selected from the group consisting of hypercholesterolemia, artherosclerosis, myocardial infarction, and cerebrovascular accident.
  • the formulation or method of the present invention may be used for reduction of body fat, such as, for example, in the treatment of obesity.
  • th particles upon introducing the composite particles at a concentration of about 0.25% for about 30 minutes into an aqueous solution comprising a bile acid or its analog at a concentration of about 0.5%, at about pH 6.8 and about 25 degrees Celsius, th particles are capable of hydrophobically binding and removing bile acids or their analogs from solution by at least about 47% at a surfactantchitosan ratio of from about 2:1 to about 3:1, and by at least about 80% at a surfactantxhitosan ratio of from about 4:1 to about 5:1.
  • all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below.
  • FIG. 1 presents a flowchart of a method of reducing cholesterol in a human subject, in accordance with the principles of the present invention
  • FIG. 2 shows a photographic recording of lecithin-chitosan particles at different lecithin:chitosan ratios after 3 hours in phosphate buffer with SKlO chitosan
  • FIGS. 3a-3b show photographic recordings of lecithin-chitosan particles at different lecithin:chitosan ratios after 5 minutes, 30 minutes, and 3 hours, respectively, in phosphate buffer, with SKl 00 chitosan;
  • FIG. 4 shows the relationship between particle size and lecithin concentration in the lecithin-chitosan particles of the present invention.
  • FIG. 5 shows a graph of the relationship between sodium cholate concentration in solution and absorbance by colorimeteric analysis.
  • the present invention provides a formulation for reduction of cholesterol in humans, the formulation comprising composite, hydrophobic, microparticles of a positively charged polymer such as chitosan, and an anionic or non-ionic surfactant, such as lecithin.
  • the chitosan and the surfactant in the composite particles are chemically bound to form composite particles, due to ionic interactions between the cationic polymer, and the anionic surfactant, as well as hydrophobic interactions between the hydrodphobic regions of the polymer and the lipid fraction of the lecithin during drying of the particles.
  • the interaction between the cationic polymer and non-ionic surfactants involves non-ionic interactions.
  • Chitosan is less effective in reducing cholesterol in humans than in rats. It was considered by the present inventor that absorption of bile acids by chitosan in small animals occurs as a result of non-specific ionic interactions between the positively- charged chitosan polymer (which competes with many other positively-charged blood proteins) and the negatively-charged bile acids, while binding of chitosan to the hydrophobic face of bile acids would be much more specific.
  • the difference in intestinal pH between humans and rats may be significant in this respect. In humans, the pH is around 7.0-7.3, while in rats the pH is around 6.2-6.5. This range is significant because chitosan is insoluble at pH values above 6.5, such that a semi-gel precipitate is formed. Insoluble chitosan has very little effect on binding bile acids.
  • non-ionic surfactants may absorb chitosan molecules via interaction with the hydrophobic tail region, resulting in the formation of an uncharged chitosan molecule that is water-insoluble at the pH of the intestine. It was thus considered that increasing the hydrophobicity of chitosan would increase its binding to bile acids in humans.
  • the formulation therefore comprises particles having a strong hydrophobic region, which are soluble in the acid conditions of the stomach, entering the small intestine in solution, wherein the microparticles bind bile salts and then precipitate.
  • Magdassi is 0.5:033. The process was carried out at pH 6. If the pH of the emulsion described by Magdassi were to be increased to above 7, at the chitosan:lecithin ratio used, precipitation of chitosan would immediately result, before interaction with bile acids could occur.
  • a formulation comprising a positively charged polymer such as chitosan and an anionic or non-ionic surfactant, such as lecithin, provides composite hydrophobic microparticles, wherein chitosan is prevented from undergoing ionic interactions with positively charged molecules in the stomach, such that the chitosan is delivered to the intestine in state which is readily available for binding bile acids.
  • the formulation of the present invention preferably comprises particles that are able to interact with bile salts to form a complex with passes through the small intestine in the form of a stable, insoluble suspension, in order to prevent digestion and disintegration by free bile salts which are able to break down the particles and interact with the lecithin.
  • a formulation comprising such composite micropatticles would therefore be highly useful in binding bile acids and thereby reducing LDL cholesterol levels in humans.
  • the formulation of the present invention is soluble in the acidic conditions of the stomach and forms suspended particles in the higher pH environment of the human small intestine. Such particles are able to interact with bile salts through hydrophobic interactions with the hydrophobic part of the bile salts, resulting in precipitation to form an insoluble agglomerate, within which the bile salts are trapped.
  • the particles of the present invention must therefore be sufficiently hydrophobic to provide strong hydrophobic interactions with the hydrophobic region of bile salts.
  • the formulation is designed such that upon entry into the human intestine, the particles remain for a short time as a stable particle suspension in intestinal medium, while interaction with bile salts takes place. The particles then precipitate as an agglomerate with the bile salts. Bile salts are thus trapped inside the polymer through hydrophobic interactions, and prevented from undergoing hydrolysis during passage through the intestine.
  • the time for which the particles remain in suspension must be sufficient to enable interaction with bile salts to occur. Particles which are insufficiently unstable in solution will undergo rapid flocculation in intestinal fluid, such that binding and entrapment of bile salts is not able to occur.
  • the particles of the present invention must therefore be capable of providing a suspension in intestinal medium, be sufficiently hydrophobic to react strongly with the hydrophobic region of bile salts, and form a precipitate with bile salts. It was found that absorption of bile salts by the lecithin-chitosan particles of the present invention is affected by hydrophobic degree and particle size. The hydrophobic degree is primarily controlled by the lecithin concentration in the particles.
  • the formulation thus provides for effective absorption of bile acids by chitosan under the high pH conditions of the human small intestine.
  • the formulation also limits emulsification of dietary fats, which are thus inaccessible to lipase, and are therefore excreted in greater amounts in the feces.
  • Microparticles are particularly suitable for the formulation of the present invention. Microparticles are solid particles having a size range of from about 1 ⁇ m to about 1 mm, as opposed to nanoparticles, which range in size from about 10 nm to about 1 ⁇ m. Nanoparticles are stable in suspension, whereas microparticles are only partially stable. The greater stability of nanoparticles in suspension would not permit such particles to precipitate in the intestine.
  • the particles of the present invention are in the range of from about 0.3 to about 1.5 ⁇ m.
  • Figure 1 presents a flow-chart of a method of reducing cholesterol in a human subject, in accordance with the principles of the present invention. As seen in the
  • the method comprises first dissolving chitosan in acid (step 10) and dissolving lecithin in water (step 12).
  • chitosan must be mixed for at least 24 hours in acid in order for solubilization to occur. Chitosan which has been dissolved under such conditions and dried may be easily re-dissolved in the acid conditions of the stomach.
  • the two solutions are then mixed at a lecithin: chitosan ratio of from about 1:1 to about 5:1 at pH 3.5 (step 14), such that the lecithin and chitosan chemically react to form composite particles of chitosan and lecithin.
  • a powder formulation is then prepared by drying (step 16).
  • the formulation is administered to the subject (step 18).
  • the particles of the formulation dissolve in the stomach of the subject (step 20) and enter the intestine of the subject in soluble form, forming a temporarily stable suspension (step 22).
  • the suspended particles form a complex with bile acids through hydrophobic interactions (step 24), which precipitates and leaves the body via the feces (step 26).
  • This removal of bile acids results in a reduction of bile salts in the intestine (step 28), causing increased hydrolysis of LDL in the blood in order to form new bile salts (step 30), resulting in decreased blood LDL levels (step 32).
  • the present invention further provides a method of producing a formulation for the reduction of cholesterol in humans.
  • the method comprises preparing a first solution of chitosan in acid, by mixing for at least 24 hours, preparing a second solution of an anionic or non-ionic surfactant, mixing the solution of chitosan with the solution of anionic or non-ionic surfactant to form composite, soluble hydrophobic particles of chitosan and surfactant and drying the particles to form a powder.
  • the chitosan solution is prepared in. hydrochloric acid and the surfactant solution is prepared in water. More preferably, the pH of each of the solutions is adjusted to a value of about 3.5 prior to mixing the two solutions together.
  • the method generally produces a powder comprising soluble solids at a concentration of from about 4% to about 8% w/w.
  • the pH of the solution of particles obtained under acid conditions may be increased to a pH value of about 7.0, and precipitation allowed to occur for about 30 minutes, after which the supernatant is filtered to obtain a pellet.
  • the pellet may then be resuspended in a minimal amount of acid medium, and added to the particles obtained in the first precipitation step, prior to spray drying.
  • hydrophobic microparticles of any of the embodiments of the present invention preferably have diameters in the range of from about 0.3 ⁇ m to about 1.5 ⁇ m.
  • any anionic or non-ionic surfactant may be used.
  • suitable anionic surfactants include phospholipids; bile salts; sodium lauryl ether sulfate; citric acid esters of monoglycerides; sodium, calcium or acid stearoyl lactylate; stearyl citrate; fatty acids or salts thereof; diacetyl tartaric acid esters of monoglycerides; or combinations thereof.
  • non-ionic surfactants include cetyl alcohol or oleyl alcohol.
  • the anionic surfactant comprises the phospholipids, lecithin (phosphatidylcholine), also known as 1, 2-diacyl-sn-glyceiO-3-phosphocholine, or PtdCho, which is represented by the following chemical structure:
  • lecithin itself has different meanings when used in chemistry and biochemistry than when used commercially.
  • Chemically, lecithin is phosphatidylcholine.
  • Phosphatidylcholine which is a polar lipid, is present in commercial lecithin in concentrations of 20 to 90%. Most of the commercial lecithin products contain about 20% phosphatidylcholine.
  • Lecithins containing phosphatidylcholine are produced from vegetable, animal and microbial sources, but mainly from vegetable sources. Soybean, sunflower and rapeseed are the major plant sources of commercial lecithin. Soybean is the most common source. Plant lecithins are considered to be GRAS (generally regarded as safe). Egg yolk lecithin is not a major source of lecithin in nutritional supplements. Eggs themselves naturally contain from 68 to 72% phosphatidylcholine, while soya contains from 20 to 22% phosphatidylcholine. The fatty acid makeups of phosphatidylcholine from plant and animal sources differ.
  • Saturated fatty acids such as palmitic and stearic, make up 19 to 24% of soya lecithin; the monounsaturated oleic acid contributes 9 to 11%; linoleic acid provides 56 to 60%; and alpha-linolenic acid makes up 6 to 9%.
  • the saturated fatty acids, palmitic and stearic make up 41 to 46% of egg lecithin, oleic acid 35 to 38%, linoleic acid 15 to 18% and alpha-linolenic 0 to 1%.
  • Soya lecithin is clearly richer in polyunsaturated fatty acids than egg lecithin.
  • Unsaturated fatty acids are mainly bound to the second or middle carbon of glycerol.
  • Lecithin has a number of advantages over other surfactants.
  • lecithin is an intrinsic part of the bile salt complex, it is cheap, and it is well recognized by bile acids.
  • any suitable positively charged polymer may be used.
  • suitable positively charged polymers include polyamines such as polylysine and polyamidoanine.
  • high molecular weight chitosan is preferably used, since low molecular weight chitosan has low hydrophobicity, and is therefore less effective in the formulation of the present invention.
  • the preferred range for high molecular weight chitosan is about 5x10 - 3xl0 6 daltons.
  • a ratio of from about 4:1 may result in excessively rapid precipitation of particles, such that insufficient time for the particles to interact with bile acids would be allowed.
  • a ratio of from about 3:1 to about 4:1 is preferable.
  • Increasing the hydrophobic part of the microparticles improves the affinity of the particles for the hydrophobic region of the bile acids and not for the hydrophilic region, leading to increased interaction with, and precipitation of, bile acids.
  • Table 3 shows that an increased lecithinxhitosan ratio, and the subsequent increase in hydrophobic character of the microparticles, resulted in an improved affinity for bile acids.
  • the range may comprise, for example, 0.2:1, 0.25:1, 0.4:1, 0.6:1, 1 :1, 1.2:1, 2:1, 2.8:1, 3:1, 4:1 or 5:1. More preferably, the range is from about 3:1 to about 4:1, such as, for example, 3:1, 3.3:1, 3.5:1, 3.7:1 or 4:1.
  • the concentration of chitosan in the formulation is optionally and preferably no greater than about 2% (w/w), such as, for example, about 0.1%, about 0.2%, about 0.25%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1%, about 1.1%, about 1.2%, about 1.25%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9% or about 2% (w/w).
  • the concentration of lecithin in the formulation is optionally and preferably in the range of from about 0.5% to about 5% (w/w).
  • the formulation of the present invention may optionally further comprise a pharmaceutically acceptable carrier, and may optionally further comprise one or more excipients, such as, for example, a binder, a filler, or a disintegrant.
  • excipients such as, for example, a binder, a filler, or a disintegrant.
  • Suitable binders may include, for example, Povidone (PVP: polyvinyl pyrrolidone), low molecular weight HPC (hydroxypropyl cellulose), low molecular weight HPMC (hydroxypropyl methylcellulose), carboxy methyl cellulose, hydroxylethyl cellulose, ethylcellulose, gelatin polyethylene oxide, acacia, dextrin, magnesium aluminum silicate, starch, and polymethacrylates.
  • PVP polyvinyl pyrrolidone
  • HPC hydroxypropyl cellulose
  • HPMC hydroxypropyl methylcellulose
  • carboxy methyl cellulose hydroxylethyl cellulose
  • ethylcellulose ethylcellulose
  • gelatin polyethylene oxide acacia
  • dextrin magnesium aluminum silicate
  • Suitable fillers may include, for example, at least one of sugars such as lactose, glucose, fructose, or sucrose; dicalcium phosphate; sugar alcohols such as sorbitol, manitol, mantitol, lactitol, xylitol, isomalt, erythritol, and hydrogenated starch hydrolysates; malto dextrines; corn starch, potato starch, sodium carboxymethycellulose, ethylcellulose and cellulose acetate, or a mixture thereof.
  • sugars such as lactose, glucose, fructose, or sucrose
  • dicalcium phosphate sugar alcohols such as sorbitol, manitol, mantitol, lactitol, xylitol, isomalt, erythritol, and hydrogenated starch hydrolysates
  • malto dextrines corn starch, potato starch, sodium carboxymethycellulose, eth
  • the disintegrant is optionally and preferably at least one of low-substituted carboxymethyl cellulose sodium, cross-linked polyvinyl pyrrolidone, sodium starch glycolate, cross-linked sodium carboxymethyl cellulose, pregelatinized starch, microcrystalline starch, water insoluble starch, calcium carboxymethyl cellulose, and low substituted hydroxypropyl cellulose magnesium aluminum silicate.
  • the formulation, of the present invention may be used in the treatment or prevention of any condition involving hypercholesterolemia, such as, for example, artherosclerosis, myocardial infarction, and cerebrovascular accident.
  • the formulation of the present invention may also be used as in the treatment of obesity by reducing body fat. Reduction of bile salts in the intestine reduces emulsification of fat, such that fat absoiption by the body is decreased. According to any of the embodiments of the present invention, the formulation or method may further comprise an additional agent for cholesterol reduction, such as, for example, a statin, a fibrate, niacin, a bile acid sequestrant, ezetimibe, or a phytosterol, or combinations thereof.
  • an additional agent for cholesterol reduction such as, for example, a statin, a fibrate, niacin, a bile acid sequestrant, ezetimibe, or a phytosterol, or combinations thereof.
  • the additional agent may optionally be provided in a combined dosage form, together with the chitosan-lecithin microparticles.
  • the additional agent may be provided in a separate dosage form, for co-administration or sequential administration, either before or after administration of the chitosan-lecithin microparticles.
  • statins examples include atorvastatin, cerivastatin, fluvastatin, lovastatin, mevastatin, pravastatin, pravastatin, rosuvastatin, and simvastatin, or combinations thereof.
  • Suitable fibrates include, for example, bezafibrate, cirpofibrate, clofibrate, gemfibrozil, and fenobirate, or combinations thereof.
  • Suitable bile acid sequestrants include, for example, cholestyramine, colesevlam, and colestipol, or combinations thereof.
  • phytosterols examples include, for example, ⁇ -sitosterol, campesterol, stigmasterol, brassicasterol, ergosterol, or combinations thereof.
  • the additional cholesterol-reducing agent is a statin; more preferably simvastatin. Since the statins affect cholesterol levels by an entirely different mechanism from that described herein for cholesterol reduction by chitosan, the effects of chitosan and statin would be expected to be additive, or even synergistic.
  • the formulation of the present invention may optionally further comprise an enteric coating layer. Enteric coating layers are formed by use of enteric polymers, such as cellulose, vinyl, and acrylic derivatives. These polymers exhibit resistance to gastric fluids, yet are readily soluble or permeable in intestinal fluid. Enteric polymeric materials are primarily weak acids containing acidic functional groups, which are capable of ionization at elevated pH.
  • enteric polymers are unionized, and therefore, insoluble. As the pH increases in the intestinal tract, these functional groups ionize, and the polymer becomes soluble in the intestinal fluids.
  • an enteric polymeric film coating allows the coated solid to pass intact through the stomach to the small intestine, where the drug is then released for absorption through the intestinal mucosa into the human body where it can exert its pharmacologic effects.
  • enteric polymers examples include cellulose acetate phthalate, cellulose acetate succinate, methylcellulose- phthalate., ethylhydroxycellulose phthalate, polyvinylacetatephthalate, polyvinylbutyrate acetate, vinyl acetate-maleic anhydride copolymer, styrene-maleic mono-ester copolymer, methyl acrylate-methacrylic acid copolymer, methacrylate-methacrylic acid-octyl acrylate copolymer.
  • Guinea pigs are useful models for investigation of the hypocholesterolemic effects of drugs. As in humans, most of the plasma cholesterol in guinea pigs is in the LDL form, making them a unique animal model with which to study hepatic cholesterol and lipoprotein metabolism. Guinea pigs show other striking similarities to humans in terms of hepatic cholesterol and lipoprotein metabolism. Guinea pig responses to dietary factors, drug treatment, ascorbic acid deficiency, oxidative stress, exercise, gender and hormonal status, undoubtedly mimic the human situation. In addition, many of the mechanisms by which guinea pigs regulate cholesterol and lipoprotein metabolism as a response to diet or drug treatment are analogous to those reported in clinical experiments. These studies clearly document the suitability and appropriateness of the guinea pig model and reinforce the importance of the use of alternatives to the more-established and more widely used animal models.
  • the two solutions were mixed for 15 minutes at 25 0 C at the following lecithin: chitosan ratios: 1:1, 2:1; 3:1; 4:1; and 5:1 to form a suspension.
  • the suspension was stirred for one hour and than transferred to a spray dryer (BUCHI mini spray dryer B-290).
  • the temperature at the entrance of the spray dryer was 12O 0 C, the degree of the aspirator was 70% and the pumping degree was 25%.
  • the powder that formed was first resuspended in hydrochloric acid (pH 3.0) to form a suspension of particles comprising chitosan at a concentration of 0.25% w/w, with varying concentrations of lecithin, to provide different ratios of lecith ⁇ v.chitosan, as follows:
  • the powder that formed was first resuspended in hydrochloric acid (pH 3.0) to form a suspension of particles comprising chitosan at a concentration of 0.25% w/w, with varying concentrations of lecithin, to provide different ratios of lecithin:chitosan, as follows:
  • An exemplary formulation comprises the following components in 100 g tablets:
  • the particles were prepared as described above, and suspended in HCl for 30 minutes. The particles were then transferred to phosphate buffer at pH 6.8 and test solutions prepared by mixing with sodium cholate for 30 minutes. Particles were then centrifuged and filtered in order to separate between the particles and the free cholate in the supernatant, before being subjected to colorimetric analysis. Controls consisted of chitosan-lecithin particles in phosphate buffer, without sodium cholate, which have some absorbance in intestinal media. Colorimetric results are presented in Table 2 below. Hypocholesterolemic effects of chitosan formulations in the guinea pig hypercholesterolemia-induced model
  • the cholesterol blood levels of guinea pigs, fed ad libitum a high level fat diet rich in lauric and myristic acids alone, or in combination with various orally- administered chitosan formulations is examined.
  • Animals Twenty male guinea pigs are used, each of body weight about 300-400 g, such that the body weight of the group does not exceed ⁇ 20% of the group mean body weight.
  • a spray drier of capacity 16 liters per hour is used. By using such a spray drier, from about 0.5 to about 1 kg can be produced per day.
  • a solution of chitosan (1%) is dissolved in 1% lactic acid for 24 hours with stirring at 25 0 C.
  • Lecithin (10%) in water is prepared by stirring for 24 hours at 25 0 C.
  • the pH of each solution is adjusted to 3.3.
  • the two solutions are mixed for 5 minutes at 45 0 C at lecithin: chitosan ratios of from about 1:1 to about 4:1 and then transferred to a spray drier.
  • Samples of lecithin:chitosan ratios 1:1, 2:1 and 3:1 are dried with 50% maltodextrin in order to obtain dry samples.
  • Samples of ratio 3.5:1 and 4:1 are dried with 80% maltodextrin.
  • Animal care Animals are handled according to the National Institute of Health and the Association for Assessment and Accreditation of Laboratory Animal Care standards. Housing consists of polyethylene cages (1 animal per cage), measuring 35 x 30 x 15 cm, with stainless steel top grill having facilities for drinking water in a glass bottle. Animals are housed under standard laboratory conditions, air conditioned and filtered (HEPA F 6/6) with adequate fresh air supply (31 air changes/hour). Animals are kept in a climate controlled environment. Temperature range is between 20 - 24 0 C and RH is between 30 - 70% with 12 hours light and 12 hours dark cycle.
  • Pelleted food is placed in hoppers on the bottom of the cage.
  • Bedding is steam sterilized clean paddy husk (Harlan, Sani-chip, cat. No. 2018SC+F), and is changed along with the cage at least twice weekly.
  • mice Prior to commencement of the study, animals are randomized using a computer generated randomization program "Research Randomizer” and divided into 5 groups of 4 animals each. Initially, all animals are fed ad libitum with the Controlled diet, D22316, detailed above, for 3 weeks. After this period, a control group is fed freely with D22316 alone. Test groups are fed with D22316 and lecithin-chitosan particles at lecithin:chitosan ratios of 3:1, 3.5:1, or 4:1 at concentrations of 0.3% lecithin, or statin at a concentration of 0.05% for a period of 4 weeks, as follows:
  • Determination of individual body weights of animals will be made once weekly during acclimation and test periods. Measurements of food consumption will be made once per 24-hour period during the acclimation period, and at least once per 24-hour period during the study period. Determination of food consumption (g/animal) is based on diet provided in hoppers and unused diet including noticable scatter.
  • blood samples (approximately 3 ml/animal) are withdrawn for blood lipid profile determination, following overnight food deprivation. Blood collection is performed by abdominal aorta puncture under isoflurane anesthesia. Animals are then sacrificed.
  • Blood samples are maintained at room temperature for at least 30 minutes, then centrifuged (5000 RCF, 10 minutes) for serum separation. Following serum separation, samples are transferred to clean vials, labeled with study code, animal number and date, and kept at -2-8 0 C until transferred for blood lipid profile analysis. Samples are packed in a closed Styrofoam receptacle containing ice pack and transferred within 24 hours of blood collection.
  • test groups are provided with lecithin.xhitosan particles in combination with statins.
  • animals are provided with D22316 alone.
  • a second control group is provided with D23316 containing statin.
  • Test groups are fed different concentrations of statins in combination with different combinations of lecithin-chitosan particles.
  • a synergistic effect is expected due to the reduction of cholesterol by two separate mechanisms.
  • the zeta potential represents the charge of the particle. As shown in the Table, zeta potential decreases with increased lecithin.-chitosan ratio.
  • Table 2 shows particle size for different concentrations of lecithin.
  • concentration of chitosan in the experiment is 0.25%.
  • the lecithinxhitosan ratios are therefore 1.2:1; 2:1; 2.8:1; and 4:1.
  • particle sizes generally increase with time and with increased lecithinxhitosan ratio.
  • Figure 2 shows dispersion of the SK-IO particles after 3 hours in phosphate buffer at lecithin:chitosan ratios of 1:1, 2:1, 3:1, 4:1 and 5:1.
  • Figures 3a-3c show dispersion of SK-100 particles, after 5 minutes, 30 minutes and 3 hours in phosphate buffer.
  • particles were stable at a ratio of 1 :1 lecithin: chitosan, and did not precipitate with time over at least 3 hours.
  • the average size of these particles was found to be around 300-400 nano microns.
  • lecithin: chitosan ratio was increased, it was found that particle size ranging from several hundred nanometers to one or two microns were obtained, and the particles lost their stability in the solution and begin to precipitate.
  • nanoparticles of diameter about 0.4 ⁇ m
  • these particles absorbed about 60% sodium cholate.
  • bile salts which are absorbed by these nanoparticles will not be able to pass through the intestine without undergoing further hydrolysis, but will instead quickly separate from the particles and remain in the intestinal tract.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Epidemiology (AREA)
  • Medicinal Chemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Molecular Biology (AREA)
  • Biophysics (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Medicinal Preparation (AREA)

Abstract

L'invention concerne une formulation pour la réduction des niveaux de cholestérol chez les hommes, comprenant du chitosan et un tensioactif anionique ou non ionique, ainsi que ses procédés de préparation et ses utilisations.
PCT/IL2007/001512 2006-12-07 2007-12-06 Formulation de chitosan pour la réduction du cholestérol chez les hommes Ceased WO2008068762A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US87315206P 2006-12-07 2006-12-07
US60/873,152 2006-12-07

Publications (2)

Publication Number Publication Date
WO2008068762A2 true WO2008068762A2 (fr) 2008-06-12
WO2008068762A3 WO2008068762A3 (fr) 2009-09-03

Family

ID=39492726

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IL2007/001512 Ceased WO2008068762A2 (fr) 2006-12-07 2007-12-06 Formulation de chitosan pour la réduction du cholestérol chez les hommes

Country Status (1)

Country Link
WO (1) WO2008068762A2 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008101723A3 (fr) * 2007-02-23 2008-11-27 Krka Composition pharmaceutique comprenant un inhibiteur d'absorption du cholestérol
WO2019077611A1 (fr) * 2017-10-18 2019-04-25 Mor Research Applications Ltd. Compositions de cannabidiol et de chitosane et leurs procédés d'utilisation
CN115154407A (zh) * 2022-02-22 2022-10-11 佑道(天津)健康咨询有限公司 一种壳聚糖亚麻籽胶交联水凝胶和制备方法及其在胃填充剂中的应用

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2755856B1 (fr) * 1996-11-21 1999-01-29 Merck Clevenot Laboratoires Microcapsules de chitine ou de derives de chitine contenant une substance hydrophobe, notamment un filtre solaire et procede de preparation de telles microcapsules
US20030092673A1 (en) * 1997-02-06 2003-05-15 Henryk Struszczyk Substance and method for reduction of lipids and cholesterol
US20030069206A1 (en) * 1998-07-10 2003-04-10 Nichols Everett J. Methods and kits for absorbing fat
WO2005072088A2 (fr) * 2003-12-11 2005-08-11 Sciperio, Inc. Compositions d'immunotherapie, methodes de preparation et d'utilisation de ces dernieres
KR100578382B1 (ko) * 2004-07-16 2006-05-11 나재운 항암제의 전달체용 수용성 키토산 나노입자 및 그 제조방법

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008101723A3 (fr) * 2007-02-23 2008-11-27 Krka Composition pharmaceutique comprenant un inhibiteur d'absorption du cholestérol
WO2019077611A1 (fr) * 2017-10-18 2019-04-25 Mor Research Applications Ltd. Compositions de cannabidiol et de chitosane et leurs procédés d'utilisation
EP3697409A4 (fr) * 2017-10-18 2021-06-02 Mor Research Applications Ltd. Compositions de cannabidiol et de chitosane et leurs procédés d'utilisation
US11679094B2 (en) 2017-10-18 2023-06-20 Mor Research Applications Ltd. Cannabidiol and chitosan compositions and methods of using the same
AU2018352039B2 (en) * 2017-10-18 2024-03-14 Mor Research Applications Ltd. Cannabidiol and chitosan compositions and methods of using the same
IL273988B1 (en) * 2017-10-18 2025-01-01 Mor Research Applic Ltd Cannabidiol and chitosan compounds, and methods of using them
US12233044B2 (en) * 2017-10-18 2025-02-25 Mor Research Applications Ltd. Cannabidiol and chitosan compositions and methods of using the same
IL273988B2 (en) * 2017-10-18 2025-05-01 Mor Research Applic Ltd Cannabidiol and chitosan compositions and methods of using the same
CN115154407A (zh) * 2022-02-22 2022-10-11 佑道(天津)健康咨询有限公司 一种壳聚糖亚麻籽胶交联水凝胶和制备方法及其在胃填充剂中的应用

Also Published As

Publication number Publication date
WO2008068762A3 (fr) 2009-09-03

Similar Documents

Publication Publication Date Title
KR102263277B1 (ko) 입자를 포함하는 제제
CN1893930B (zh) 胃肠道递送系统
EP3083031B1 (fr) Microcapsules avec un revêtement polymère comprenant un lipide et un agent actif
DK2654463T3 (en) ANTIOXIDANTS IN FISH OIL POWDER AND TABLETS
JP2004501170A (ja) 体重管理のための組成物及び方法
EP3188713B1 (fr) Procédé permettant d'induire la satiété
WO2019008101A1 (fr) Forme posologique solide à enrobage entérique comprenant des sels d'acides aminés d'acides gras oméga-3
JP4755633B2 (ja) 下痢止め剤および抗潰瘍剤として使用される、ペクチンとリン脂質とを含有する医薬組成物
Wu et al. Oral quercetin nanoparticles in hydrogel microspheres alleviate high-altitude sleep disturbance based on the gut-brain axis
WO2008068762A2 (fr) Formulation de chitosan pour la réduction du cholestérol chez les hommes
CA2671177A1 (fr) Melange et procede pour reduire le cholesterol en utilisant des microparticules hydrophobes
JP2005295854A (ja) 健康食品および栄養物質の吸収改善を目的とする組成物
WO2007109884A1 (fr) Composition piégeant les matières grasses comprenant un polysaccharide cationique non digestible et un agent émulsifiant
WO2023037053A1 (fr) Composition comprenant des gouttelettes de matière grasse ou d'huile et procédé de production de la composition
US20210275572A1 (en) Methods for reducing cholesterol with superabsorbent materials
BR112014032472B1 (pt) Processo para obter uma composição compreendendo beta-glicano, quitina e quitosana, e composição resultante do mesmo
KR100186907B1 (ko) 이온 복합체를 이용한 대장약물 전달시스템
JPH09241169A (ja) 化合物の放出性及び吸着性を有するゲル状組成物
US20040091545A1 (en) Solid polyunsaturated fatty acid compositions
HK1230132B (en) Microcapsules with polymeric coating comprising a lipid and an active agent
HK1230132A1 (en) Microcapsules with polymeric coating comprising a lipid and an active agent
Shiv Design and evaluation of floating drug delivery system for antimicrobial drug

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07849545

Country of ref document: EP

Kind code of ref document: A2

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 07849545

Country of ref document: EP

Kind code of ref document: A2