Reducing the reproductive capacity of mammals
10646501 ยท 2020-05-12
Assignee
Inventors
Cpc classification
A01K2207/20
HUMAN NECESSITIES
A61K2300/00
HUMAN NECESSITIES
A61K31/343
HUMAN NECESSITIES
A61K2300/00
HUMAN NECESSITIES
A61K31/665
HUMAN NECESSITIES
A61K31/665
HUMAN NECESSITIES
A61K31/336
HUMAN NECESSITIES
A61K31/585
HUMAN NECESSITIES
International classification
A61K31/665
HUMAN NECESSITIES
A61K31/585
HUMAN NECESSITIES
A61K31/343
HUMAN NECESSITIES
Abstract
Provided are compositions and methods for reducing the reproductive capacity of mammals. The compositions and methods involve the use and administration of (a) a diterpenoid epoxide comprising a triptolide skeleton and which causes ovarian follicle depletion in female mammals and (b) an organic diepoxide which causes ovarian follicle depletion in female mammals.
Claims
1. A method of controlling the size of a population of non-human mammals, providing to a population of non-human mammals an effective amount of a composition comprising: (a) a diterpenoid epoxide or a salt thereof which causes ovarian follicle depletion in female mammals selected from the group consisting of triptolide, tripdiolide, 16-hydroxytriptolide, triptonide or a salt thereof, and (b) an organic diepoxide which causes ovarian follicle depletion in female mammals selected from the group consisting of 4-vinylcyclohexene diepoxide (VCD), glycerol diglycidyl ether, 3,4-epoxy-cyclohexyl-methyl-3,4-epoxycyclohexyl carboxylate, 1,4-cyclohexanedimethanol diglycidyl ether, ethylene glycol diglycidyl ether, resorcinol glycidyl ether and 1,4-butanediol diglycidyl ether, wherein the composition is in the form of an edible bait that can be consumed by the male and female non-human mammals and wherein (a) and (b) are present in an amount to synergistically reduce the reproductive capacity of the male and female non-human mammals while not otherwise negatively effecting general health of the male and female non-human mammals.
2. The method of claim 1, wherein the composition is provided to the non-human mammals in an urban public transit system.
3. The method of claim 1, wherein the composition is provided to the non-human mammals in an urban subway system.
4. The method of claim 1, wherein the composition is provided to the non-human mammals in the New York City subway system.
5. The method of claim 1, wherein the non-human mammals are rodents.
6. The method of claim 1, wherein the non-human mammals are rats.
7. The method of claim 1, wherein male and female non-human mammals consume the composition.
8. The method of claim 1, wherein the composition is provided to the non-human mammals in an urban public transit system and the composition is provided throughout the urban public transit system.
9. The method of claim 1, wherein the size of the population of the non-human mammals is reduced.
10. The method of claim 1, wherein the population of the non-human mammals is suppressed.
11. The method of claim 1, wherein male and female non-human mammals consume the composition and the reproductive capacity of the male and female non-human mammals is reduced.
12. The method of claim 1, wherein the non-human mammals become sterilized by consuming the composition.
13. The method of claim 1, wherein the diterpenoid epoxide is triptolide.
14. The method of claim 1, wherein the organic diepoxide is 4-vinylcyclohexene diepoxide.
15. The method of claim 1, wherein (a) is triptolide and (b) is 4-vinylcyclohexene diepoxide.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1) The exemplary embodiments of the present invention will be described in connection with the appended drawing figures.
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17) It will be appreciated that the figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of illustrated embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
(18) The present invention provides a composition suitable for depleting ovarian follicles in female mammals, comprising:
(19) (a) a diterpenoid epoxide comprising a triptolide skeleton and which causes ovarian follicle depletion in female mammals when incorporated into the composition, i.e., used in combination with the epoxide (b), and
(20) (b) an organic diepoxide which causes ovarian follicle depletion in female mammals.
(21) Triptolide is a well-known diterpenoid epoxide and many derivatives and analogs of this compound are also well-known and may be used in the present invention.
(22) As a reference, the triptolide skeleton may be represented by the following structure:
(23) ##STR00002##
(24) Of course, compounds of the present invention have a variety of different substituents on the skeleton. Examples of such compounds are described below.
(25) In a preferred embodiment of the invention, the diterpenoid epoxide comprising a triptolide skeleton (a) is represented by formula (I):
(26) ##STR00003##
where
(27) X.sup.1 is H, R.sup.1, OH or OR.sup.1,
(28) X.sup.2 is H, R.sup.1, OH, OR.sup.1, O or Y,
(29) X.sup.3 is H or OH.
(30) X.sup.4 is H, OH or OR.sup.1,
(31) R.sup.1 is a C.sub.1-4 alkyl group,
(32) Y is (CR.sup.2R.sup.3O).sub.nP(O)(O.sup.Z.sup.+).sub.2,
(33) each R.sup.2 is, independently, H, C.sub.1-6 alkyl, aryl-C.sub.1-6 alkyl-, C.sub.1-6 cycloalkyl or aryl,
(34) each R.sup.3 is, independently, H, C.sub.1-6 alkyl, aryl-C.sub.1-6 alkyl-, C.sub.3-6 cycloalkyl or aryl,
(35) or R.sup.2 and R.sup.3, together with the carbon atom to which they are bonded form a C.sub.3-7 cycloalkyl group,
(36) wherein any alkyl or cycloalkyl group in R.sup.2 or R.sup.3 may be optionally substituted with one to five substituents selected from the group consisting of halo, C.sub.1-6 alkoxy and NR.sup.aR.sup.b,
(37) wherein any aryl group in R.sup.2 or R.sup.3 may be optionally substituted with one to five substituents selected from the group consisting of C.sub.1-6 alkyl, C.sub.1-6 alkoxy, NR.sup.aR.sup.b, nitro and cyano,
(38) n is 1, 2 or 3,
(39) each Z is H,
(40) R.sup.a and R.sup.b are each, independently, H, C.sub.1-6 alkyl, C.sub.3-6 cycloalkyl or aryl,
(41) or R.sup.a and R.sup.b, together with the nitrogen atom to which they are bonded, form a pyrrolidino, piperidino, piperanino, azetidino, morpholino, or thiomorpholino group,
(42) or a salt thereof.
(43) In a preferred embodiment of the invention, X.sup.1 is H, CH.sub.3, OH or OCH.sub.3.
(44) In another preferred embodiment of the invention, X.sup.2 is H, CH.sub.3, OH, OCH.sub.3 or O.
(45) In another preferred embodiment, X.sup.2 is Y. In a particularly preferred embodiment of the invention, when X.sup.2 is Y, then X.sup.1, X.sup.3 and X.sup.4 are H.
(46) In another preferred embodiment of the invention, X.sup.3 is H.
(47) In another preferred embodiment of the invention, X.sup.4 is H, OH or OCH.sub.3.
(48) In a preferred embodiment of the invention, (a) is triptolide, tripdiolide, 16-hydroxytriptolide, triptonide or minnelide, including salts thereof.
(49) In a particularly preferred embodiment, (a) is triptolide.
(50) Detailed descriptions and methods of making compound (a) are provided in a variety of references, such as U.S. Pat. Nos. 6,294,546, 7,626,044, 6,548,537, 6,004,999, 8,268,882 and WO 2010/129918, each of which is incorporated herein by reference. Mixtures of different compounds within the scope of (a) are included in the present invention.
(51) Component (b) of the inventive composition is an organic diepoxide which is capable of causing ovarian follicle depletion in female mammals. In a preferred embodiment of the invention, the organic diepoxide contains 8 to 14 carbon atoms. In another preferred embodiment of the invention, the organic diepoxide contains two to four rings, inclusive of the two epoxide rings.
(52) In a preferred embodiment of the invention, the organic diepoxide comprises at least one member selected from the group consisting of 4-vinylcyclohexene diepoxide (VCD), glycerol diglycidyl ether, 3,4-epoxy-cyclohexyl-methyl-3,4-epoxycyclobexyl carboxylate, 1,4-cyclohexanedimethanol diglycidyl ether, ethylene glycol diglycidyl ether, resorcinol glycidyl ether and 1,4-butanediol diglycidyl ether. Mixtures of diexpoxides are within the scope of the invention.
(53) Other organic diepoxides that may be used in the present invention include 1,2,3,4-diepoxybutane, 1,2,4,5-diepoxypentane, 1,2,5,6-diepoxypentane, 1,2,6,7-diepoxypentane, 1,2,7,8-diepoxyoctane, 1,2,3,4-diepoxycyclohexane, 1,2,5,6-diepoxycyclooctane, 9,10,12,13-diepoxystearic acid, 3,4-epoxy-6-methyl-cyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, resorcinoldiglycidyl ether, hexaepoxyysqualene, bis-(2,3-epoxy-2-methylpropyl)ether, bis-(3,4-epoxybutyl)ether, ethylene glycol bis-(2,3-epoxy-2-methylpropyl)ether, 2,3-epoxy-2-ethylhexyl-9,10-epoxystearate, 2-ethyl-1,3-hexanediol bis-(9,10-epoxystearate), 2,3-bis(glycidyloxy)-1,4-dioxane, bis-(3,4-epoxycyclohexylmethyl) adipate, bis-(3,4-epoxy-methylcyclohexylmethyl) adipate, 3,4-epoxy-6-methylcyclohexylmethyl 3-4-epoxy-6-methylcyclohexanecarboxylate, limonene dioxide and bis-(2,3-epoxycyclopentyl) ether. Such compounds are described in, for example, Weil, Industrial Hygiene Journal, July-August 1963, pp. 305-325 and Van Duuren, Annals New York Academy of Sciences, 1969, pp. 633-651, both incorporated herein by reference.
(54) In a preferred embodiment of the invention, the organic diepoxide comprises 4-vinylcyclohexene diepoxide. In a very particularly preferred embodiment of the invention, (a) is triptolide and (b) is 4-vinylcyclohexene diepoxide.
(55) The chemical reactivity of the epoxides can determined in an alkylating assay using 4-(p-nitrobenzyl) pyridine (NBP) based on the method reported in Detection of epoxides with 4-(p-nitrobenzyl) pyridine. Agarwal et. al. 1979, Bull. Environm. Contam. Toxicol. 23, 825-829, incorporated herein by reference.
(56) The biological activity of the epoxides can be evaluated in an in vitro bioassay using rat pup ovaries based on method reported in Characterization of a rat in vitro ovarian culture system to study the ovarian toxicant 4-vinylcyclohexene diepoxide. Devine et. al. 2002, Taxicol. Appl. Pharmacol. 184, 107-115, incorporated herein by reference. Biological activity can be determined by follicle counts in ovarian sections after week long culture with micro molar concentrations of the epoxide. In general, biologically active epoxides will also be chemically active as well but not vice versa.
(57) The present invention also includes a method of inducing ovarian follicle depletion in a female mammal, comprising administering an effective amount of the composition described above to the female mammal.
(58) In a preferred embodiment of the invention, the mammal is a human or a non-human mammal. Examples of non-human mammals include rodents (e.g., rats, mice, squirrels, prairie dogs, gophers, woodchucks, hamsters, nutria, beavers, voles), muskrats, cats, dogs, pigs, horses, cattle, coyotes, foxes, sheep, deer, goats, stoats, possums, opossums, rabbits, hares, kangaroos, wallabies, badgers, camels, elephants, burros, raccoons, bears, groundhogs, moles, bats and boars, for example.
(59) The mammals listed above may be used in any embodiment of the invention described herein.
(60) The present invention also includes a method of reducing the reproductive capacity of a mammal, comprising administering an effective amount of the composition described above to the mammal.
(61) In a preferred embodiment of the invention, the mammal is a female. In another embodiment of the invention, the mammal is a male. It is noted that triptolide oral exposure is known to compromise male rat fertility to ultimate sterility. Thus, both male and females can be treated according to the present invention. In a preferred embodiment of the invention, the mammal is sterilized by the treatment in the present invention, i.e., the animal has lost its reproductive capacity.
(62) The present invention also includes a method of controlling population size of a population of non-human mammals, comprising administering an effective amount of the composition described above to the population of non-human mammals. In this aspect of the invention, a number of animals, i.e., a population, are targeted for treatment over a range of area, e.g., in a park or wild-life preserve, agriculture, concentrated animal feeding operations, commercial businesses, residential, Federal lands. This embodiment of the invention is particularly useful in controlling the rodent (e.g., rat) population in an urban public transit system. For example, an urban subway system. New York City's subway system, for example, is well-known to have large rodent population. In this embodiment of the invention, the inventive composition is provided for the rodents to ingest throughout the system. Such a treatment is expected to reduce the size of the animal population, and possibly eliminate the population.
(63) The present invention also includes all of the methods described above in which (a) and (b) are administered separately if desired, i.e., (a) and (b) are not incorporated into a single composition. In addition, while (a) and (b) will preferably administered at the same time, it is also within the scope of the present invention with respect to this embodiment that (a) and (b) can be administered at different times, with the understanding that both (a) and (b) will be present together to provide the synergistic effect provided by the present invention. Preferably, (a) and (b) are administered within 24, 12, 6, 3, 2 or 1 hour, or less, of each other.
(64) In accordance with various embodiments, the composition of the present invention is configured to cause sterility in mammals by inducing ovarian depletion of follicles. According to various aspects of these embodiments, all stages of follicles are targeted. To cause permanent loss of ovarian function, the finite primordial pool of follicles is targeted. To cause rapid reduction in offspring production, growing follicles are targeted.
(65) Component (b) of the present invention (e.g., VCD) is used to target primordial/primary follicles, and component (a) (e.g., triptolide) is used to target growing follicles. The combination is used to permanently suppress reproduction in the mammals so treated by the present invention. Additionally, triptolide is known to reduce fertility in male mammals, and so the composition reduces fertility in both male and female mammals. The composition can also be used to accelerate ovarian failure in mammals, such as peri-menopausal women.
(66) A dose of an active agent may vary according to the purpose of treatment and type of animal. However, in accordance with exemplary embodiments of the disclosure, the composition includes about 1 mM to about 750 mM, or about 1 mM to about 500 mM, or about 10 mM to about 100 mM of (b) and about 1 nM to about 10 mM, or about 5 nM to about 1 mM, or about 5 nM to about 20 nM of (a). These ranges include all specific values and subranges therebetween, such as 10 nM, 25 nM, 50 nM, 100 nM, 250 nM, 500 nM, 5 mM, 25 nM, 50 mM and 250 mM. Surprisingly and unexpectedly, the compositions of the present invention were found to deplete all stages of ovarian follicles. The depletion is thought to result from the synergistic combination of (b) and (a), which is thought to allow for the use of lower concentrations of each of the agents, compared to compositions that do not include the combination, and which results in higher depletion percentages of follicles.
(67) For in vitro culture applications, the molar ratio of (a) to (b) may range from 1/5 to 1/75,000, including all specific values and subranges therebetween, such as 1/10, 1/25, 1/50, 1/100, 1/250, 1/500, 1/1,000, 1/2,500, 1/5,000, 1/10,000, 1/25,000 and 1/50,000. For in vivo application (e.g., a bait), the corresponding molar ratio is generally 1/5 to 1/500, inclusive of all specific values and subranges therebetween, such as 1/10, 1/25, 1/50, 1/100 and 1/250.
(68) For In vitro culture applications, the weight ratio of (a) to (b) generally ranges from 1/2 to 1/50,000, including all specific values and subranges therebetween, such as 1/10, 1/25, 1/50, 1/100, 1/250, 1/500, 1/1,000, 12,500, 1/5,000, 1/10,000 and 1/25,000. For in vivo application (e.g., a bait), the corresponding weight ratio is generally 1/5 to 1/500, inclusive of all specific values and subranges therebetween, such as 1/10, 1/25, 1/50, 1/100 and 1:250.
(69) Although compositions including VCD were studied for inducing follicle depletion, it was found that VCD aloneas the only active ingredient-did not cause premature ovarian failure at low concentrations, or short exposure durations <15 days. Premature ovarian failure is when no more ovulations occur in spite of eggs/follicles being present in an ovary. For compositions and methods to function as a means of population control, the ovarian failure desirably occurs rapidly, for example within 10 days of treatment for rodents.
(70) In accordance with various embodiments, a method of inducing ovarian follicle depletion includes the steps of providing a composition comprising VCD and triptolide, wherein the composition induces depletion of multiple stages of ovarian follicles. For example, the composition may cause depletion of primordial, secondary, and tertiary follicles and of corpora lutea. In accordance with further aspects, the combination may cause an increase in primordial follicle depletion and more complete destruction of the primordial follicles, compared to compositions including only VCD.
(71) The composition and method disclosed herein can be used to sterilize various mammals (e.g., rodents, pigs, coyotes, dogs, cats, horses and the other animals described above), control the population of such animals, and the like by feeding the composition to mammal populations. As noted above, the composition reduces fertility in male mammals, so administering the composition to both males and females of a population is thought to further reduce the population, compared to compositions that only affect fertility of either males or females.
(72) In accordance with additional embodiments, a non-human mammalian female having ovarian follicle depletion induced by the administration of a composition comprising VCD and triptolide, wherein the composition induces depletion of multiple stages of ovarian follicles, is provided. The animal may be used to, e.g., study menopause and post-menopausal treatments and may be used as an animal model for animals, such as humans.
(73) The mammals may be fed in accordance with a variety of techniques, such as gavage and using bait. When gavage is used, the concentration of (b) (e.g., VCD) typically ranges from about 50 to about 200 mg/kg/day of the feed and the amount of (a) (e.g., triptolide) ranges from about 25 g/kg body weight to about 100 g/kg body weight of the composition. These ranges include all specific values and subranges therebetween, including 35, 60, 75, 90, 125, 150 and 175 g/kg body weight.
(74) When bait is used, in accordance with exemplary embodiments, the bait is formulated, such that: the active ingredients consumed do not cause adverse side effects, bait takes occur in the presence of other food sources, the bait is environmentally neutrali.e., the active ingredients do not persist in the environment and no residual tissue accumulation occurs, which could lead to secondary exposure of non-target animals, the active ingredients should not put humans at risk, and the bait production should be scalable for production. The bait may be solid, semisolid, or liquid.
(75) Compositions in accordance with the present invention may include the ingredients described herein as well as additional and/or alternative inert materials, preservatives, and other constituents typically found in similar compositions. In the case where exemplary inert materials and/or preservatives are listed, these ingredients are merely exemplary, and it is understood that other similar ingredients may be substituted for the materials listed in the examples below.
EXAMPLES
(76) Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified.
In Vitro
Comparative Example 1
(77)
Comparative Example 2
(78)
(79)
Example 3
(80)
Example 4
(81)
In Vivo
Example 5
(82) In vivo studies were performed using a 15-day feeding trial of juvenile female Sprague-Dawley rats. The VCD concentration was held constant at 75 mM and the triptolide concentration was varied as noted below. The Experiment design was as follows:
(83) Control no active ingredients (n=6)
(84) VCD+triptolide 25 g/kg body weight (n=7)
(85) VCD+triptolide 50 g/kg body weight (n=7)
(86) VCD+triptolide 100 g/kg body weight (n=7)
(87) The experiment was designed to assess: palatability and quantity of bait consumed, health of rats (body weight recorded daily), and ovaries collected for follicular analysis. The rats had access to standard chow along with the control or treatment bait for 15 consecutive days.
(88)
(89) Efficacy In Vivo
(90) A bait composition containing two active ingredients, 4-vinylcyclohexene diepoxide at 0.099% by weight and triptolide at 0.0012% was provided to immature Sprague Dawley female rats for 15 successive nights in the presence of unlimited water and laboratory rat chow and they consumed >10% of their body weight/night. The next day after the end of dosing the female rats were bred for 21 days with untreated, proven adult male breeders. The control rats that consumed an emulsion without active ingredients gave birth to average litters of 12.2 rat pups after an average of 39.7 days from the start of dosing. The rats that consumed the inventive bait composition had an average litter size of 4.3 pups after an average of 55.9 days from the start of dosing. However, 2 of the 8 rats that drank the inventive composition never delivered a litter and another 2 rats delivered a litter of 1 pup.
(91) Additionally in the group fed the inventive bait, the rat that consumed the least amount of all 8 rats, 8 mg/kg body weight versus 16 mg/kg body weight for the other 7 rats, gave birth to a litter of 15 pups-clearly indicating an inverse dose response relationship between composition consumed and number of pups/litter. These results are consistent with the data presented above which were reduced follicle counts after consumption of the inventive bait. In that data set there was a more pronounced effect of bait on growing follicles and corpora lutea suggesting there were fewer ovulations. Therefore, consumption of the composition of the present invention by female rats reduced ovarian ovulations to the extent that there are 65% fewer pups produced and the delayed ovulations significantly extend the time to delivery. Combining these two effects in rats that have short lives, less than 1 year in the wild, exerts a profound effect on the total of number of rat pups born per female rat and ultimately the overall population size.
Example 6: In Vivo Application of a Bait Composition
(92) Bait compositions with a constant concentration of VCD and increasing triptolide concentrations were prepared.
(93) Immature female rats consumed bait with constant VCD (0.099% concentration) combined with increasing triptolide concentrations, low 3.99 g/ml, medium 7.96 g/ml, and high 11.92 g/ml for 15 days.
(94) Immature female rats had unlimited chow and water during entire treatment period. Day 0 represents the first night of having bait with active ingredients triptolide and VCD presented during lights off time period. The next morning the amount of bait consumed was measured and the rats were assessed for general health and weighed. The results are shown in
(95) Immature female rats ate bait with high triptolide concentration and VCD at 0.099% for 15 days. The day after the last bait take the female rats were bred with untreated, proven male breeder rats. Number of pups per litter were counted at post natal day 4. The results are shown in
(96) Immature female rats ate control bait, no active ingredients, and treated females ate bait with VCD at 0.099% and high dose of triptolide for 15 days. The day after end of baiting the treated female rats were bred with proven male breeder rats. Days to delivery were counted from day 0 of breeding to parturition. The data is presented in
Example 7: In Vitro Assay
(97) In vitro bioassay of follicle depletion, ovaries cultured for 8 days with different chemicals
(98) Controlno chemicals, Triptolide5 nM (Trip), Diepoxides. RDE, CHDE, Quetol, ERL 4221, BDE, GDE, each at 30 M+Trip 5 nM
(99) Ovaries were prepared for histological analysis for determination of follicle depletion
(100) Compared chemical (reactivity in epoxide assay) to biological activity (follicle depletion)
(101) TABLE-US-00001 Chemical reactivity Diepoxide Biological activity 4 RDE 1 5 GDE 2 6 BDE 3 3 CHDE 4 2 Quetol 5 1 ERL 42221 6
(102) Ranking, 1least chemical reactivity/biological activity, 6most chemical reactivity/biological activity
CONCLUSIONS
(103) 1. In a previous experiment none of these diepoxides tested at 30 M caused significant follicle depletion.
(104) 2. In this experiment, Triptolide (Trip) at 5 nM did not cause significant follicle depletion.
(105) 3. Only when Triptolide and GDE, BDE, CHDE, Quetol and ERL 4221 were combined was there significant follicle depletion. Triptolide+RDE combination did not cause significant follicle depletion.
(106) 4. ERL 4221 is best illustration of relationship between chemical and biological activity. ERL 4221 was least chemically reactive while being most biologically active when combined with Trip.
(107) 5. The combination of Trip and these diepoxides GDE, BDE, CHDE, Quetol, ERL 4221 caused significant follicle depletion apparently via synergistic interactions.
(108) The present invention has been described above with reference to a number of exemplary embodiments and examples. It should be appreciated that the particular embodiments shown and described herein are illustrative of the preferred embodiments of the invention and its best mode, and are not intended to limit the scope of the invention as set forth in the claims. It will be recognized that changes and modifications may be made to the embodiments described herein without departing from the scope of the present invention. These and other changes or modifications are intended to be included within the scope of the present invention, as expressed in the following claims and the legal equivalents thereof.
(109) Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.