WO1994025042A1

WO1994025042A1 - Method for treating atherosclerosis with psyllium

Info

Publication number: WO1994025042A1
Application number: PCT/US1994/004756
Authority: WO
Inventors: Shirley Chen; Victor Fulgoni
Original assignee: Kellogg Company
Priority date: 1993-05-03
Filing date: 1994-05-02
Publication date: 1994-11-10
Also published as: AU6778694A; AU668045B2

Abstract

The invention is a method of preventing atherosclerosis via administering psyllium to a subject in need of atherosclerosis prevention. The psyllium is preferably administered as a farinaceous foodstuff, such as a ready to eat cereal. Prophylactic treatment of recurrence is described, as is total prevention. The method may be used alone, or in combination with other therapies.

Description

METHOD FOR TREATING ATHEROSCLEROSIS

WITH PSYLLIUM

FIELD OF THE INVENTION

This invention relates to prevention and treatment of atherosclerosis. More particularly, it relates to prevention and treatment of atherosclerosis by administration of psyllium to a subject.

BACKGROUND AND PRIOR ART

Atherosclerosis, sometimes referred to as "nodular sclerosis", is a form of arteriosclerosis characterized by the accumulation of irregularly distributed lipid deposits in the intima of large and medium sized arteries. These deposits are associated with arterial fibrosis and calcification. Severe atherosclerosis leads to reduction of the arterial lumen, and a predisposition to thrombosis. Ischemic manifestations include angina pectoris, myocardial infarction, strokes, intermediate claudication and, in some cases, gangrene of the lower extremities.

The foregoing listing of conditions associated with atherosclerosis will suggest that efforts have been made to treat the condition once it has been established and/or diagnosed. Current prevention strategies have been directed, by and large, to reducing risk factors associated with atherosclerosis rather than atherosclerosis per se. Without question, the emphasis in this area has been on lowering blood cholesterol through the dietary management of individuals at greater risk for developing atherosclerosis. One approach toward achieving this end is a passive or substitution strategy of diet management, i.e., the reduction of fat and cholesterol from the diet by substitution of low-fat or lower fat foods, (e.g., substituting skim milk for whole milk). Another, more aggressive approach has been the treatment of the risk factor with antihyperlipidemic, and/or anti- hypercholesterolemic drugs in addition to dietary management. These drugs include various heterocyclic compounds, such as indole derivatives (U.S. Patent No. 5,195,446); iminocarbonyl derivatives (U.S. Patent Nos. 5,189,058 and 5,185,358), mevalonolactones (U.S. Patent No. 5,185,328), and so forth. Other approaches address the enzymatic mechanisms by which complex lipids and cholesterol esters are manufactured and/or metabolized, seeking to modify these mechanisms in a way that reduces the serum levels of cholesterol or other lipids. All of these approaches, however, address only one part of a much broader condition. While high blood cholesterol has clearly been shown to be a controllable risk factor in developing atherosclerosis, it is not the only factor. Further, an ability to lower serum cholesterol levels does not de facto mean that atherosclerosis can be treated, prevented or alleviated.

A natural product which has become known for its cholesterol lowering efficacy is psyllium. This material is a mucilaginous substance, derived from the seeds of the Plantago genus. Initially, psyllium was used extensively in bulk laxatives. Eventually, it was employed in foodstuffs, as it was associated with digestion regulating properties, satiation, and "fullness feeling", as is noted in, e.g., U.S. Patent Nos. 3,574,634 and 4,348,379.

The earliest suggestions of psyllium's usefulness as a cholesterol lowering agent may be found in U.S. Patent No. 3,148,114. This reference suggests that ground husks of whole psyllium (Plantago psyllium) may be used to lower blood cholesterol. U.S. Patent No. 4,849,222 discloses a medicinal composition containing psyllium seed gum, and nonabsorbable, nondigestible polyol polyester as an agent for lowering blood cholesterol levels. Other examples of the patent literature which disclose medicinal type compositions which contain psyllium include Colliopoulos et al., U.S. Patent No. 4,459,280; Day et al., U.S. Patent No. 4,824,672; Day et al., U.S. Patent No. 4,883,788; Leitz et al., U.S. Patent No. 4,877,627; Colliopoulos, U.S. Patent No. 5,009,916; and Day, U.S. Patent No. 5,102,664.

Attempts have been made to incorporate psyllium into foodstuffs, so that the resulting high-fiber foods can be consumed as part of a meal or other aspect of a low-fat diet, without any connotation or association with medicines. These plant or grain-based products are designed so that their organoleptic properties are accepted by the consumer and easily replace lower fiber, non-efficacious staple foods. Examples of the patent literature involving psyllium incorporated into foodstuffs are U.S. Serial Nos. 817,244 and

819,569 both filed January 6, 1992, now U.S Patent Nos.

and No.

, both of which are incorporated by reference. These patents teach psyllium containing ready to eat cereals. Additional examples of cereals containing psyllium are set forth by Moskowitz, U.S. Patent No. 4,766,004; Ringe U.S. Patent No. 5,024,996; and Ringe et al., U.S. Patent No. 5,026,689. Other foodstuffs which include psyllium are taught in U.S. Patent Nos. 5,095,008 and 5,950,140 both of which teach cookies with incorporated psyllium, U.S. Patent No. 5,015,486, which teaches microwavable muffins, and U.S. Patent No. 5,024,996, which teaches almond paste containing compositions, such as marzipan.

The cited patents generally teach that psyllium containing compositions are useful as bulking agents and/or laxatives, as well as for reducing blood or serum cholesterol levels. There are no teachings in the references of the use of psyllium to prevent or to treat atherosclerosis. Indeed, one cannot generalize from a serum cholesterol lowering effect to anti-atherosclerotic efficacy.

It has now been found, however, that atherosclerosis can be prevented and treated by administering psyllium to a subject in need of such treatment. The manner in which the psyllium is administered is preferably in the form of a foodstuff, although this is not required.

How the invention is achieved will be seen in the disclosure which follows. The model used, the so-called "SEA quail" model, is established as an animal model which provides results directly correlatable to humans. Thus, the experiments now set out permit one to conclude that the claimed invention is efficacious in humans.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Example 1

The experimental model used in all of the experiments described herein is the "susceptible to experimental atherosclerosis" or "SEA" Japanese quail.

Subject animals (eighty-four, approximately six month old males) were randomized into seven treatment groups, caged individually. The birds were acclimated for one week prior to the experimental period by being fed "diet 1" as described in Table 1, which follows. During this period of time, as well as throughout the experiments, the birds were given free access to food and water.

Each group received a different diet, as described in Table 1. These diets were designed to be nearly nutritionally identical, save for the presence or absence of dietary cholesterol and the source of dietary fiber. Each diet included 10% dietary fiber. The diets were fed to the quail for eight weeks.

Psyllium was administered either as a ready-to-eat cereal, the recipe for which is given in Serial Nos. 817,244 and 819,569, now U.S. Patent Nos.

, and

, the disclosure of which is incorporated by reference, or as untreated psyllium. For untreated psyllium, samples from two different batches were used, referred to as "Psyllium 1" and "Psyllium 2", respectively. For convenience, the recipe for the cereal is provided in Example 3, which follows. When the cereal was used, it was ground and mixed with the other dietary components.

In the diets, cellulose without added cholesterol acts as a negative control. Cellulose is a highly purified source of dietary fiber, does not contain soluble dietary fiber, and does not reduce blood cholesterol. Similarly, the cellulose diet augmented with dietary cholesterol acts as another control, demonstrating the hypercholesterolemic effect of a diet including cholesterol but no soluble fiber. These two regimes can then be compared to diet containing wheat bran a natural source of dietary fiber with levels of soluble fiber, and psyllium another natural source of dietary fiber with high levels of soluble fiber. Wheat bran was tested with and without cholesterol. This allows one to determine if an anti-atherosclerotic effect can be attributed to natural source of dietary fiber with varying levels of soluble fiber.

TABLE 1

COMPOSITION OF DIETS (IN PARTS) CONTAINING DIFFERENT DIETARY FIBERS FED TO MALE SEA QUAIL

FOR EIGHT WEEKS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Diet 1 2 3 4 5 6 7

Fiber source cellulose cellulose wheat bran wheat bran Fiberwise psylliuml psyllium2

Fiber amount 10. .0 10.0 24.6 24.6 53.3 14.8 13.4

Soy protein

isolate (92%) 30 .0 30.0 25.9 25.9 24.7 29.3 29.3

Lard 10.0 10.0 9.2 9.2 8.9 9.8 9.8

Corn starch 29.7 29.7 23.9 23.9 4.7 28.8 28.8

Dextrose 10.0 10.0 9.4 9.4 1.0 9.3 9.3

Cholesterol 0 0.5 0 0.5 0.5 0.5 0.5

Choline chloride 0 .2 0.2 0.2 0.2 0.2 0.2 0.2

DL-Methionine 0 .3 0.3 0.3 0.3 0.3 0.3 0.3

CaCO3 5.0 5.0 5.0 5.0 5.0 5.0 5.0

AIN mineral mix 4 .0 4.0 4.0 4.0 4.0 4.0 4.0

AIN vitamin mix 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Total Parts 99.7 100.2 103.0 103.5 103. 3 101.7 101. 1

Example 2

Each bird was weighed at the beginning of the study, and at two week intervals thereafter. Pre-weighed portions of diet were provided weekly, and food remaining at the end of every two weeks was measured, so that the total amount of food consumed could be determined.

At the end of the eight week period, blood was obtained from non-fasted animals via venipuncture of the right jugular vein. The sampled blood was allowed to clot at room temperature, after which serum was recovered via centrifugation. The serum was assayed as described infra.

After blood sampling, the animals were decapitated, and major arteries removed (i.e., the thoracic aorta and brachycephalic arteries), as a single piece of tissue, which was then cleaned of adventitia.

The sampled serum was tested to determine total cholesterol. This was done using an enzymatic cholesterol reagent (Sigma), within 24 hours of sampling, on 5 ul samples prepared as follows. High density lipoprotein (HDL) cholesterol was measured by diluting 10 ul of serum with 500 ul distilled water, followed by addition with mixing of 20 ul of 0.5 M CaCl₂ and 50 ul of 1% bovine lung heparin. After setting at refrigerator temperature overnight, HDL cholesterol was measured in the clear supernatant procured after centrifugation. The sum of very low density lipoprotein (VLDL) cholesterol and low density lipoprotein (LDL) cholesterol was determined by subtracting the HDL values from total serum cholesterol levels.

Arterial analyses were carried out by longitudinally opening each artery, photographing it, and studying the resulting photographs for various parameters. Specifically, total surface area of the arteries was calculated, as was the area covered by macroscopic atherosclerotic lesions. (These data were measured via planar planimetry from enlarged photographs).

After the photographs were prepared, the arteries were blotted, weighed, and finely ground in a glass tissue homogenizer with isopropanol. Tissue (arterial) cholesterol was extracted from the homogenate by mixing overnight at room temperature. Cholesterol analyses were carried out, using the same enzymatic reagent described supra. Results were calculated as milligrams cholesterol per gram of arterial tissue on a wet weight basis.

During the study, some animals died before the end of the eight week period. These were subjected to gross necropsies and histopathologic examination. Further, in the analysis which follows, all groups were compared, statistically, with the two cellulose groups discussed supra. using a one-tailed t-test.

Tables 2 and 3 summarize the results of these experiments. The studies on atherosclerotic plaque formation, and arterial cholesterol concentrations (Table 2) are discussed first.

There were no macroscopic atherosclerotic lesions observed in any animals fed diets without cholesterol supplements (the "cellulose" and "wheat bran" values of Table 2) . There is a significant increase in blood cholesterol when these two diets are supplemented with dietary cholesterol (items 2 and 4 in Table 2) . Ten of 12 (83%) animals fed diets containing cellulose plus cholesterol showed grossly visible atherosclerotic lesions, as did 7 of 12 (58%) of the animals fed wheat bran plus cholesterol. There was no significant difference in degree of macroscopic atherosclerosis (29±40% versus 21±35%), nor in total arterial cholesterol (18.57±15.25 g/mg, versus 15.42±12.59 mg/g). Thus, wheat bran, an excellent source of dietary fiber but little soluble fiber, had no observable impact on prevention of atherosclerosis.

In contrast, all three groups fed diets containing psyllium and cholesterol showed dramatic and startling decreases in all atherosclerotic indices as compared to the other groups. Of the 30 animals which survived, only two showed any evidence of atherosclerosis. Indeed, the values obtained for both plaque formation and arterial cholesterol content, are nearly the same as those resulting from diets without added cholesterol.

The results presented in Table 3, i.e., the analysis of serum cholesterol, are of significant interest. When the animals were fed cholesterol, serum cholesterol levels increased significantly. Neither cellulose nor wheat bran significantly decreased blood cholesterol, although wheat bran tended to decrease total, low-density, and very low density lipoproteins. Wheat bran had no effect on HDL. In the first comparison, the data are nearly identical. In the second case, wheat bran did cause a significant drop in serum cholesterol.

TABLE 2

ATHEROSCLEROTIC PLAQUE AND ARTERIAL CHOLESTEROL CONCENTRATIONS (MEAN±SD) IN THE

BRACHIOCEPHALIC ARTERIES AND THORACIC AORTAS OF MALE SEA QUAIL FED DIFFERENT DIETARY FIBERS FOR EIGHT WEEKS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Treatment dence of Atherosclerosis Arterial cholesterol rosclerosis (% of total lumenal (mg/g)

surface area covered)

Cellulose 0/12 0±0a 4.47±1.37a

Cellulose + cholesterol 10/12 29±40b 18.57±15.25b

Wheat bran 0/12 0±0a 4.92±1.53a

Wheat bran + cholesterol 7/12 21±35b 15.42±12.59b

Fiberwise# + cholesterol 1/12 2±7a 5.90±2.80a

Psyllium 1 + cholesterol 0/10 0±0a 5.41±2.75a

Psyllium 2 - cholesterol 1/8 0.4±la 6.38±4.07a

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - a P<0.01 compared to cellulose + cholesterol,

b P<0.01 compared to cellulose.

TABLE 3

SERUM CHOLESTEROL VALUES (MEAN±SD) OF MALE SEA QUAIL FED VARIOUS FIBER CONTAINING DIETS FOR A PERIOD OF EIGHTS WEEKS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Treatment Total ULDL + LDL HDL

cholesterol cholesterol cholesterol

(mg/dl) (mg/dl) (mg/dl)

Cellulose 312±44a 54±18a 258±39a

Cellulose + cholesterol 1655±862b 1322±869b 333±72b

Wheat bran 289±29a 35±16ab 254±31a

Wheat bran +cholesterol 1097±764b 736±733bc 361±75b

Fiberwise# + cholesterol 461±196ab 216±204ab 245±45a

Psyllium 1 + cholesterol 346±177a 149±164ad 197±42ab

Psyllium 2 + cholesterol 390±208a 180±181ad 210±62ad

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - a P<0.01 compared to cellulose + cholesterol, b P<0.01 compared to cellulose, c P<0.05 compared to cellulose + cholesterol, d P<0.05 compared to cellulose.

As was seen in the analysis of atherosclerosis, however, wheat bran had absolutely no effect whatsoever. Thus, one conclusion that can be drawn from these results is that efficacy in lowering serum cholesterol is not necessarily correlatable to an atherosclerosis preventive effect.

In contrast, all psyllium containing formulations caused a dramatic drop in serum cholesterol levels, which confirms the studies reported in, e.g., the two pending applications reported supra. The studies in these references, however, present no information on atherosclerosis prevention and, as is seen from the foregoing experiments, such a connection is not to be expected.

Example 3

Psyllium-containing intermediate nuggets were prepared having a final composition on a dry weight basis as set forth in Table 4 below.

Table 4

Ingredient Percent Dry Basis

Psyllium Husks with 1.5% Citric Acid 75.0

Oat Bran 15.0

Rice Flour 5.0

Sucrose 5.0

100.0

The psyllium husks had been sterilized by extrusion. All of the ingredients were first mixed and then directly expanded using an extruder. The product exit temperature from the extruder was 190°F and the moisture content after cooling was 31%. The product was then dried for 30 minutes at 210°F to a moisture content of 3%. The nuggets were then combined in the following cereal. Table 5

Ingredients Percent Dry Basis

Bran Cook at 80.15%:

Whole Wheat, Chopped 44.71

Oat Brim 11.98

Sugar 8.27

Wheat Bran 7.19

Prune Powder 2.33

Rice Flour 2.08

High Fructose Corn Syrup 1.60

Salt 0.88

Barley Malt Syrup 0.80

Guar Gun 0.09

Calcium Carbonate 0.08

Trisodium Phosphate 0.05

Caramel Color 0.04

Vitamin B3 0.01828

Iron, Reduced 0.01645

Zinc Oxide 0.00685

Vitamin B2 0.00155

Folic Acid 0.00037

Psyllium Nuggets at 16.65%;

75% Psyllium Husk with 1.5% Citric Acid 12.50

15% Oat Bran 2.50

5% Sucrose 0.82

5% Rice Flour 0.82

<0.1 % Annatto Color 0.0083

coating at 3.2%:

Sucrose 3.00

Salt 0.20

Vitamin Spray:

Vitamin A & D cone, 3% BHT 0.02285 Vitamin B6 0.00234 Vitamin B1 0.00137 Vitamin B12

100 The bulk ingredients were first mixed. The flavoring ingredients comprising sugar, salt, color, HFCS and malt syrup (previously diluted with warm water) were then added to and mixed with the bulk ingredients in a rotating cooker. The bulk ingredients were cooked for 65 minutes at 17 psi, cooled and screen separated. Thereafter, psyllium-containing intermediate nuggets having a composition as set forth in Table 4 above, and prepared as described, were blended with the bran, and the mixture cooked to completion in a mixer. The mixture was then milled, pelletized, and the pellets dried to a moisture content of about 20%. The product was tempered hot for 30 minutes, flaked and toasted at 370°F. The flakers were then sprayed with the coating composition together with Vitamins A and D, B6, B12 and Bl. The finished flakes had a food moisture content of about 3%.

The foregoing examples describe a method for preventing, reducing or treating atherosclerosis in a subject. The method, simply stated, involves administering to a subject in need thereof an amount of psyllium sufficient to prevent or reduce atherosclerosis. The subject of interest is preferably a human, typically a human particularly susceptible to development of atherosclerosis. Such individuals are easily identified from the population at large via a number of parameters, including prior incidence of the pathological condition, family history showing predilection for the disease, a high risk lifestyle, and so forth. The invention also embraces preventing recurrence of atherosclerosis, also by consumption of psyllium.

The psyllium may be administered in a number of ways. The survey of the art in this field indicates that while psyllium may be administered "as is", it is unpleasant in this form. Indeed, it is far more preferable to administer the psyllium in the form of a foodstuff, such as those described in the art. Farinaceous products are particularly preferred, with ready to eat cereals being especially preferred.

Formulations which are described in, e.g.. Serial Nos. 817,244 and 819,569, now U.S. Patent Nos. , the

disclosures of which are incorporated by reference are especially preferred psyllium-containing ready-to-eat cereals.

The manner of administration and amount of psyllium to be administered may vary, depending upon the subject in question. Generally, it is preferred that the psyllium be administered in an amount of about 3 grams per "serving", a "serving" referring to a full meal, snack, or other point at which food is consumed. The psyllium may be spread over a number of different food items consumed in a meal, or in one food stuff. In a preferred embodiment, the foodstuff contains about 1.5g-6.0g of psyllium per ounce. It is especially preferred that the subject consume anywhere from about 3 grams to about 25 grams of psyllium daily. Most particularly preferred are regimes where the subject consumes from about 3 to about 12 grams of psyllium daily. These ranges, of course, must be treated as very general guidelines, as age, prior medical history, and other factors will determine how much psyllium should be consumed.

"Preventing" atherosclerosis as this term is used herein refers both to avoiding any atherosclerosis "ab initio", but also to prophylaxis in eliminating recurrence of the condition or aggravation thereof. Thus, the method can be used in connection with other therapies, in addition to a therapeutic regime, such as drug based therapy, is completed.

The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, it being recognized that various modifications are possible within the scope of the invention.

Claims

We claim :

1. Method for preventing atherosclerosis in a subject comprising administering an atherosclerosis preventing amount of psyllium to a subject in need thereof.

2. The method of claim 1, wherein said psyllium is administered in the form of a foodstuff.

3. The method of claim 2, wherein said foodstuff is farinaceous.

4. The method of claim 2, wherein said foodstuff is a cereal.

5. The method of claim 4, wherein said cereal is a ready to eat cereal.

6. The method of claim 2, wherein said foodstuff is a baked product.

7. The method of claim 6, wherein said baked product is a muffin, a cookie, or a pie crust.

8. The method of claim 2, wherein said foodstuff is a confection.

9. The method of claim 8, wherein said confection contains almond paste.

10. The method of claim 2, wherein said psyllium is contained in said foodstuff in an amount ranging from about 1.5 grams to about 6.0 grams per ounce of foodstuff.

11. The method of claim 1, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 25.0 grams per day.

12. The method of claim 11, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 12.0 grams daily.

13. Method for alleviating atherosclerosis comprising administering to a subject with atherosclerosis an atherosclerosis reducing amount of psyllium.

14. The method of claim 13, wherein said psyllium is administered in the form of a foodstuff.

15. The method of claim 14, wherein said foodstuff is farinaceous.

16. The method of claim 14, wherein said foodstuff is a cereal.

17. The method of claim 16, wherein said cereal is a ready to eat cereal.

18. The method of claim 14, wherein said foodstuff is a baked product.

19. The method of claim 18, wherein said baked product is a muffin, a cookie, or a pie crust.

20. The method of claim 14, wherein said foodstuff is a confection.

21. The method of claim 20, wherein said confection contains almond paste.

22. The method of claim 14, wherein said psyllium is contained in said foodstuff in an amount ranging from about 1.5 grams to about 6.0 grams per ounce of foodstuff.

23. The method of claim 13, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 25.0 grams daily.

24. The method of claim 23, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 12.0 grams daily.

25. Method for preventing recurrence of atherosclerosis in a subject previously treated for atherosclerosis comprising administering to said subject an amount of psyllium sufficient to prevent recurrence of atherosclerosis.

26. The method of claim 25, wherein said psyllium is administered in the form of a foodstuff.

27. The method of claim 26, wherein said foodstuff is farinaceous.

28. The method of claim 26, wherein said foodstuff is a cereal.

29. The method of claim 28, wherein said cereal is a ready to eat cereal.

30. The method of claim 25, wherein said foodstuff is a baked product.

31. The method of claim 30, wherein said baked product is a muffin, a cookie, or a pie crust.

32. The method of claim 25, wherein said foodstuff is a confection.

33. The method of claim 23, wherein said confection contains almond paste.

34. The method of claim 25, wherein said psyllium is contained in said foodstuff in an amount ranging from about 1.5 grams to about 6.0 grams per ounce of foodstuff.

35. The method of claim 25, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 25.0 grams per day.

₃₆. The method of claim 35, comprising administering said psyllium in an amount ranging from about 3.0 grams to about 12.0 grams daily.