CA2139326A1 - Diagnostic procedure for evaluating short stature etiology - Google Patents
Diagnostic procedure for evaluating short stature etiologyInfo
- Publication number
- CA2139326A1 CA2139326A1 CA 2139326 CA2139326A CA2139326A1 CA 2139326 A1 CA2139326 A1 CA 2139326A1 CA 2139326 CA2139326 CA 2139326 CA 2139326 A CA2139326 A CA 2139326A CA 2139326 A1 CA2139326 A1 CA 2139326A1
- Authority
- CA
- Canada
- Prior art keywords
- growth hormone
- trp
- ghrp
- phe
- administered
- 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.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/74—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving hormones or other non-cytokine intercellular protein regulatory factors such as growth factors, including receptors to hormones and growth factors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/68—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving proteins, peptides or amino acids
- G01N33/6872—Intracellular protein regulatory factors and their receptors, e.g. including ion channels
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2333/00—Assays involving biological materials from specific organisms or of a specific nature
- G01N2333/435—Assays involving biological materials from specific organisms or of a specific nature from animals; from humans
- G01N2333/575—Hormones
- G01N2333/61—Growth hormones [GH] (Somatotropin)
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Molecular Biology (AREA)
- Chemical & Material Sciences (AREA)
- Urology & Nephrology (AREA)
- Biomedical Technology (AREA)
- Hematology (AREA)
- Immunology (AREA)
- Cell Biology (AREA)
- Food Science & Technology (AREA)
- Biochemistry (AREA)
- Biotechnology (AREA)
- Pathology (AREA)
- Medicinal Chemistry (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Microbiology (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Endocrinology (AREA)
- Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
- Investigating Or Analysing Biological Materials (AREA)
Abstract
A diagnostic procedure for evaluating the etiology of short stature in children which comprises measuring the effect of a growth hormone releasing compound and the effect of GHRP-6 or a peptide which releases growth hormone by the same cellular mechanism alone or in combination on the growth hormone levels in the blood of the child.
Description
W O 94/00759 2 1 3 9 3~ PC~r/US93/05955 FIELD OF INVENTION
The present invention provides a method for diagnosing the etiology of short stature in children.
R~C~(j~G~.v OF THE INVENTION
Stimulated growth hormone GH secretion using a variety of provocative agents including l-dopa, clonidine, arginine and insulin have been assessed in slowly or poorly growing children in an attempt to determine the etiology of short stature. However, the reliability of those tests has been the subject of significant debate because differential GH secretion in subsets of short-statured children makes the data difficult to interpret. For example, provocative agents whose action is mediated by growth hormone releasing hormone (GHRH) cannot differentiate hypothalamic defects from pituitary defects in the GH neuroendocrine axis. Thus, the isolation, characterization and synthesis of growth hormone-releasing hormone (GHRH) provided a potentially valuable diagnostic tool for evaluation of growth hormone (GH) deficiency and differentiation between hypothalamic and pituitary decrements (O. Butinandt, Acta Paediatr. Scand [suppl.]
1989; 349, 93-9). However, its diagnostic value has been surprisingly limited because of marked variability in GH secretion following administration of GHRH (A. Pertzelan et al., W 094/00759 PC~r/US93/05955 Hormone Res 1985; 22, 24-31). In an attempt to explain this variability, it was proposed that some children with GH deficiency due to hypothalamic etiology were hyporesponsive to a single dose of GHRH because of chronic deprivation of the exposure to the peptide (E.A.
Schriock et al., J. Clin. Endocrinol. Metab.
1984, 58: 1043-1049). This explanation was not completely adequate because subnormal GH
responses to a single GHRH injection were also observed in GH sufficient children (P. Chatelain et al., J. Clin. Endocrinol. Metab. 1987: 65:
387-394)-Another proposal to explain variable responses to provocative GHRH tests was that GH
releasing activity of the peptide varied with the time of its administration (P.M. Martha et al., J. Clin. Endocrinol. Metab. 1988; 67, 449-454) .
Endogenous hypothalamic-somatotroph secretory rhythm affect the GH response to GHRH in humans (J. Deversa et al., Clinical Endocrinology 1989;
30, 367-377), and rats in vivo (G.H. Albini et al., Clinical Pharmacol Ther. 1988, 43, 696-700) and in vitro (G.S. Tannenbaum et al., Endocrinology 1989; 124, 1380-1388) and this rhythm might cause the variation in GH
responsivity following exogenous GHRH. Thus, debate has considered whether spontaneous as well as stimulated GH secretion must be characterized to reliably identify children with low GH
secretion. Clearly, the greatest information would be derived from both methods, but the high cost and inconvenience of extended hospitalization for long-term analysis of spontaneous GH secretion limits the practical W094/00759 2 1 3 9 3 2 ~ PCT/US93/05955 _ _3_ utility of this procedure. On the other hand, the low cost and relatively quick procedure makes provocative testing most attractive, so long as the problem of response variability could be resolved. U.S. patents 5,065, 747 issued November 19, 1991, and 4,844,096 issued July 4, 1989 describe methods for reducing the variability in GH levels by administering somatostatin prior to provocative testing or prior to determining the etiology of growth hormone deficiency.
The present invention provides a new and more effective way to use stimulated GH
secretion as a reliable and effective tool for diagnosing GH secretory deficits in short-statured children.
The present invention provides adiagnostic procedure for determining whether short stature in a child is due to a deficiency in growth hormone releasing hormone (GHRH) or GHRP-6 or a peptite which causes release of growth hormone (GH) by the same cellular mechanism. The diagnostic procedure of the present invention is carried out by establishing baseline levels of growth hormone in the blood of the child having short stature, then administering sequentially a growth hormone releasing compound, GHRP-6, or a peptide which causes growth hormone release by the same cellular mechanism as GHRP-6, or the combination of GHRH and GHRP-6 and then measuring the changes, if any, in the levels of growth hormone in the blood of the short-statured child resulting from the three different 2 i3~ _4_ PCT/US93/05955 administrations. Children deficient in GHRH
would respond best to GHRH. Children deficient in the endogenous analog for GHRP-6 would respond best to GHRP-6. Children deficient in both GH
secretogogues would respond best to the combination of GHRH and GHRP-6. The growth hormone releasing compound can be administered either first or second, generally on different days, i.e., before or after the GHRP-6 or peptide which acts similarly at a cellular level. The quantities of each agent to be administered is any quantity known to be effective in causing an increase in growth hormone levels. i.e., an amount which will stimulate release of growth hormone.
There are a number of factors that are relevant to the underlying basis of the present invention. Recent studies show that GHRH may not be the only endogenous agent that provides stimulation for GH secretion. A xenobiotic hexapeptide, GHRP-6, which has different binding characteristics from GHRH (E.E. Codd et al., Neuropharmacology 1989; 28, 1139-1144 and A.D.
Blake, et al., J. Endocrinol. 1991; 129, 11-19) and utilizes a different somatotroph second messenger system (K. Cheng et al., Endocrinol.
1989; 124, 2791-2798) is a GH secretagogue that potentiates GHRH efficacy (C.Y. Bowers et al., J.
Clin. Endocrinol. Metab. 1990; 70, 975-982).
Furthermore, like GHRH, GHRP-6 is effective in some, but not all, short-statured children to whom it is administered (C.Y. Bowers et al., J.
Clin. Endocrinol. Metab. 1991; 74, 292-298 and V.
Merica et al., 1992: Growth Hormone Responses to a Second Generation Growth Hormone Releasing W094~00759 PCT/US93/05955 ~-52~ 3a~ .
Peptide and to GH Releasing Hormone [GHRH] in Growth Hormone Deficient Children, Endocrine Society Abstracts, 74th Annual Meeting, San Antonio, TX, June 24-27, No. 477, pg 171). The different mechanisms and synergistic effects of GHRH and GHRP-6 in vitro and in vivo, suggest the existence of an endogenous analog for the synthetic hexapeptide that may be physiologically relevant. Support for this hypothesis derives from two of our recent studies. In one study, passive immunization against endogenous GHRH in rats, reduced GHRP-6 activity approximately 90%
(B.B. Bercu et al., Endocrinology 1992; 130, 2579-2586). These data demonstrated the requirement of endogenous GHRH for expression of GHRP-6 activity. A reciprocal relationship, i.e., dependence of GHRH upon a yet unidentified, endogenous analog of GHRP-6 may also exist.
Thus, in individuals deficient in the endogenous GHRP-6 analog, GHRH efficacy would be blunted, whereas in individuals deficient in GHRH, GHRP-6 efficacy would be blunted. Support for this hypothesis derives from our recent finding in which old rats that were hyporesponsive to individually administered GHRH or GHRP-6, were hyperresponsive to co-administered GHRH and GHRP-6 lR.F. Walker et al., Life Science 1992;
49, 1499-1504 and B.B. Bercu et al., Endocrinol.
Abstracts, Annual Meeting San Antonio, TX, June 24-27, 1992). Hyposensitivity to the individually administered peptides suggested that more than one, interdependent, endogenous, - stimulatory factor contributed to GH secretion.
GHRP-6 is a hexapeptide having the following structure:
~393~ -6-His-D-Trp-Ala-Trp-D-Phe-Lys-NH2.
In practicing the present invention, GHRP-6, as well as all other synthetic peptides in the same class of drugs that release GH by the same cellular mechanism as GHRP-6 referred to hereinafter as GHRP-6 or analogs thereof, will be used as diagnostic agents in children for differential diagnosis of growth hormone (GH) deficiency of various etiologies. Responses to GHRP-6 or analogs thereof will be compared with those resulting from administration of the endogenous GH releasing hormone (GHRH) and from co-administration of GHRH and GHRP-6 to better understand the cause of growth deficits in short statured children. Since GHRP-6 acts as a functional analog for a yet undefined GHRH co-factor or co-secretagogue, hyposensitivity to a provocative GHRH challenge could represent deficiency of that endogenous co-secretagogue (represented by GHRP-6) rather than down-regulation of pituitary receptor or deficits in GH synthesis and/or release. Such a child could have normal GHRH concentrations/secretion and a normal pituitary, but display poor GH secretion in the absence of the endogenous GHRP-6 analog.
On the other hand, this child would respond normally to a challenge dose of GHRP-6 because his/her complement of GHRH would be available.
In contrast, a child with GHRH deficiency, but having normal concentrations of GHRP-6 endogenous analog would respond normally to a provocative dose of GHRH, and poorly to GHRP-6 since the child's GHRH complement would be lacking. The paradox in this hypothesis is that a normal W094/00759 213~3a~ PCT/US93/05955 _ --7--response to a provocative challenge by a given GH
secretagogue (GHRH or GHRP-6 or analog thereof) will be observed for the peptide that is lacking or deficient in the slow-growing child.
Poor responses to individually administered GHRH and GHRP-6 would suggest a deficiency of both endogenous GH secretagogues, and/or a defect in pituitary GH
synthesis/release.
Thus, the present invention provides a new clinical application for GHRP-6 and other synthetic GH secretagogues that function by the same mechanism as GHRP-6. The invention is important because it not only provides a reliable method for identifying children with low GH
secretory capability, but also helps diagnose the etiology of GH deficiency and perhaps provide a key to appropriate treatment.
In practicing the present invention, children who are shorter than other children of a comparable age who have been identified as in need potentially of growth hormone or some agent that would stimulate growth hormone production would be monitored for the purpose of establishing a baseline level of growth hormone in the blood. Once baseline levels are established, the child is administered GHRH at a dose ranging from 100 ng/kg body weight to 100 mg/kg body weight. The GHRH peptide is administered and blood samples are monitored over a period of 120 minutes to determine whether the exogenous GHRH increased growth hormone levels.
After the effects of GHRH administration are determined, the child is administered GHRP-6 or an analog thereof at a dose of 100 ng/kg body 2l393~6 weight to 1 mg/kg body weight for one day. Blood samples are measured for any change in growth hormone levels. Additional administration of peptides may be made but a day of rest, i.e., a day during which neither peptide type is administered should intervene administration days. The dosage amount can be varied to determine optimal dosages. The changes, if any, in growth hormone levels to either or both of GHRH or GHRP-6 or analog thereof will provide an insight to the etiology of the short stature condition of the child.
In addition to GHRH, any growth hormone releasing compound can be utilized in the diagnostic procedure of the present invention.
However, GHRH is the preferred growth hormone releasing compound for use in the claimed invention. The growth hormone releasing compounds which may be used in practicing the present invention are any such compounds known to induce growth hormone (GH) secretion and include growth hormone releasing hormone (GHRH) (1-44) and analogs GHRH (1-40) and GHRH (1-29) thereof.
There are numerous growth hormone releasing compounds known in the art and any of these known compounds will be useful in practicing the present invention. U.S. Patent 4,622,312 provides an excellent description of GHRH and analog thereof, which can be used in the presently claimed invention. Reissue patent RE33,699 provides a summary of patents which teach growth hormone releasing compounds. The growth hormone releasing compounds taught in each of the following U.S. patents are suitable for invention. Reissue Patent No. RE 33,699 provides 9 2139~26 a summary of patents which teach growth hormone releasing compounds taught in each of the following U.S. patents are suitable for use in the method of the present invention:
U.S. RE 33,699 1-4 U.S. 4,517,181 2 U.S. 4,518,586 1-4 U.S. 4,528,190 1-2 10 U.S. 4,529,595 1-4 U.S. 4,562,175 1-2 U.S. 4,563,352 1-4 U.S. 4,585,756 1-2 U.S. 4,595,676 1-2 15 U.S. 4,605,643 1-2 U.S. 4,610,976 1-2 U.S. 4,617,149 1-4 U.S. 4,622,312 1-4 10 U.S. 4,626,523 1-2 20 U.S. 4,649,131 1-4 19 U.S. 4,710,382 1-2 U.S. 4,774,319 The above U.S. patents, and in particular the portions indicated above by column and line number, are incorporated herein by reference as teaching growth hormone releasing compounds that are useful in the practice of the presently claimed invention.
The term GHRP-6 and analogs thereof means GHRP-6 and any peptide compound that releases GH by the same cellular mechanism. In addition to GHRP-6, the pentapeptide Tyr-D-Trp-Gly-Phe-Met-NH2 (K. Cheng et al., Endocrinol.
1989; 124, 2791-2798) is a useful analog in the release of GH. Other compounds considered analogs of GHRP-6 for purposes of the present invention have been reported. For example, C.Y.
Bowers et al., Endocrinol. 1980; 106, 663 teaches in addition to Tyr-D-Trp-Gly-Phe-Met-NH2, compounds Tyr-D-Phe-Gly-Phe-Met-NH2 and Trp-D-W O 94/00759 PC~r/US93/05955 21393~ o-Phe-Pro-Phe-Met-COOH as being useful in the release of growth hormone, and GHRP-1 having the formula Ala-His-D-~-Nal-Ala-Trp-D-Phe-Lys-NH2 disclosed in the 74th Annual Meeting of the Endocrine Society, June 24-27, 1992, p. 182, San Antonio, Texas, is also useful in the release of growth hormone. Also, F.A. Momany et al., Endocrinol. 1981; 108, 31 teaches the following compounds as being useful in the release of growth hormone: Try-Ala-D-Trp-Phe-Met-NH2; Tyr-D-Trp-D-Trp-Phe-Met-NH2; Tyr-D-Trp-D-Trp-Phe-NH2;
Tyr-D-Trp-D-Trp-Phe-COOH; and D-Trp-D-Trp-Phe-NH2. Additionally, F.A. Momany et al., Endocrinol. 114, lS31 (1984) teaches the following compounds as being useful in the release of growth hormone: His-D-Trp-Ala-Trp-D-Phe-NH2; His-D-Trp-Ala-Trp-D-Phe-Lys-NH2; Tyr-D-Trp-Ala-Trp-D-Phe-NH2; His-D-Trp-Ala-Trp-D-Phe-Arg-NH2; and His-D-Trp-Ala-Trp-D-Phe-Lys-COOH.
All of these compounds are useful in the diagnostic procedure of the present invention.
The growth hormone levels in the blood of the child can be measured by any well known procedures, e.g., using an immunoradiometric assay as described by C.Y. Bowers et al., J. Clin Endocrinol. Metab 1990; 70, 975-982 or any other contemporary, scientifically accepted method.
Once the short-statured child is diagnosed as having either a deficiency in GHRH
or GHRP-6 the appropriate replacement therapy can ensue whereby either a growth hormone releasing compound or a GHRP-6 or analog thereof or a combination of both GH secretagogues is administered to the child.
The present invention provides a method for diagnosing the etiology of short stature in children.
R~C~(j~G~.v OF THE INVENTION
Stimulated growth hormone GH secretion using a variety of provocative agents including l-dopa, clonidine, arginine and insulin have been assessed in slowly or poorly growing children in an attempt to determine the etiology of short stature. However, the reliability of those tests has been the subject of significant debate because differential GH secretion in subsets of short-statured children makes the data difficult to interpret. For example, provocative agents whose action is mediated by growth hormone releasing hormone (GHRH) cannot differentiate hypothalamic defects from pituitary defects in the GH neuroendocrine axis. Thus, the isolation, characterization and synthesis of growth hormone-releasing hormone (GHRH) provided a potentially valuable diagnostic tool for evaluation of growth hormone (GH) deficiency and differentiation between hypothalamic and pituitary decrements (O. Butinandt, Acta Paediatr. Scand [suppl.]
1989; 349, 93-9). However, its diagnostic value has been surprisingly limited because of marked variability in GH secretion following administration of GHRH (A. Pertzelan et al., W 094/00759 PC~r/US93/05955 Hormone Res 1985; 22, 24-31). In an attempt to explain this variability, it was proposed that some children with GH deficiency due to hypothalamic etiology were hyporesponsive to a single dose of GHRH because of chronic deprivation of the exposure to the peptide (E.A.
Schriock et al., J. Clin. Endocrinol. Metab.
1984, 58: 1043-1049). This explanation was not completely adequate because subnormal GH
responses to a single GHRH injection were also observed in GH sufficient children (P. Chatelain et al., J. Clin. Endocrinol. Metab. 1987: 65:
387-394)-Another proposal to explain variable responses to provocative GHRH tests was that GH
releasing activity of the peptide varied with the time of its administration (P.M. Martha et al., J. Clin. Endocrinol. Metab. 1988; 67, 449-454) .
Endogenous hypothalamic-somatotroph secretory rhythm affect the GH response to GHRH in humans (J. Deversa et al., Clinical Endocrinology 1989;
30, 367-377), and rats in vivo (G.H. Albini et al., Clinical Pharmacol Ther. 1988, 43, 696-700) and in vitro (G.S. Tannenbaum et al., Endocrinology 1989; 124, 1380-1388) and this rhythm might cause the variation in GH
responsivity following exogenous GHRH. Thus, debate has considered whether spontaneous as well as stimulated GH secretion must be characterized to reliably identify children with low GH
secretion. Clearly, the greatest information would be derived from both methods, but the high cost and inconvenience of extended hospitalization for long-term analysis of spontaneous GH secretion limits the practical W094/00759 2 1 3 9 3 2 ~ PCT/US93/05955 _ _3_ utility of this procedure. On the other hand, the low cost and relatively quick procedure makes provocative testing most attractive, so long as the problem of response variability could be resolved. U.S. patents 5,065, 747 issued November 19, 1991, and 4,844,096 issued July 4, 1989 describe methods for reducing the variability in GH levels by administering somatostatin prior to provocative testing or prior to determining the etiology of growth hormone deficiency.
The present invention provides a new and more effective way to use stimulated GH
secretion as a reliable and effective tool for diagnosing GH secretory deficits in short-statured children.
The present invention provides adiagnostic procedure for determining whether short stature in a child is due to a deficiency in growth hormone releasing hormone (GHRH) or GHRP-6 or a peptite which causes release of growth hormone (GH) by the same cellular mechanism. The diagnostic procedure of the present invention is carried out by establishing baseline levels of growth hormone in the blood of the child having short stature, then administering sequentially a growth hormone releasing compound, GHRP-6, or a peptide which causes growth hormone release by the same cellular mechanism as GHRP-6, or the combination of GHRH and GHRP-6 and then measuring the changes, if any, in the levels of growth hormone in the blood of the short-statured child resulting from the three different 2 i3~ _4_ PCT/US93/05955 administrations. Children deficient in GHRH
would respond best to GHRH. Children deficient in the endogenous analog for GHRP-6 would respond best to GHRP-6. Children deficient in both GH
secretogogues would respond best to the combination of GHRH and GHRP-6. The growth hormone releasing compound can be administered either first or second, generally on different days, i.e., before or after the GHRP-6 or peptide which acts similarly at a cellular level. The quantities of each agent to be administered is any quantity known to be effective in causing an increase in growth hormone levels. i.e., an amount which will stimulate release of growth hormone.
There are a number of factors that are relevant to the underlying basis of the present invention. Recent studies show that GHRH may not be the only endogenous agent that provides stimulation for GH secretion. A xenobiotic hexapeptide, GHRP-6, which has different binding characteristics from GHRH (E.E. Codd et al., Neuropharmacology 1989; 28, 1139-1144 and A.D.
Blake, et al., J. Endocrinol. 1991; 129, 11-19) and utilizes a different somatotroph second messenger system (K. Cheng et al., Endocrinol.
1989; 124, 2791-2798) is a GH secretagogue that potentiates GHRH efficacy (C.Y. Bowers et al., J.
Clin. Endocrinol. Metab. 1990; 70, 975-982).
Furthermore, like GHRH, GHRP-6 is effective in some, but not all, short-statured children to whom it is administered (C.Y. Bowers et al., J.
Clin. Endocrinol. Metab. 1991; 74, 292-298 and V.
Merica et al., 1992: Growth Hormone Responses to a Second Generation Growth Hormone Releasing W094~00759 PCT/US93/05955 ~-52~ 3a~ .
Peptide and to GH Releasing Hormone [GHRH] in Growth Hormone Deficient Children, Endocrine Society Abstracts, 74th Annual Meeting, San Antonio, TX, June 24-27, No. 477, pg 171). The different mechanisms and synergistic effects of GHRH and GHRP-6 in vitro and in vivo, suggest the existence of an endogenous analog for the synthetic hexapeptide that may be physiologically relevant. Support for this hypothesis derives from two of our recent studies. In one study, passive immunization against endogenous GHRH in rats, reduced GHRP-6 activity approximately 90%
(B.B. Bercu et al., Endocrinology 1992; 130, 2579-2586). These data demonstrated the requirement of endogenous GHRH for expression of GHRP-6 activity. A reciprocal relationship, i.e., dependence of GHRH upon a yet unidentified, endogenous analog of GHRP-6 may also exist.
Thus, in individuals deficient in the endogenous GHRP-6 analog, GHRH efficacy would be blunted, whereas in individuals deficient in GHRH, GHRP-6 efficacy would be blunted. Support for this hypothesis derives from our recent finding in which old rats that were hyporesponsive to individually administered GHRH or GHRP-6, were hyperresponsive to co-administered GHRH and GHRP-6 lR.F. Walker et al., Life Science 1992;
49, 1499-1504 and B.B. Bercu et al., Endocrinol.
Abstracts, Annual Meeting San Antonio, TX, June 24-27, 1992). Hyposensitivity to the individually administered peptides suggested that more than one, interdependent, endogenous, - stimulatory factor contributed to GH secretion.
GHRP-6 is a hexapeptide having the following structure:
~393~ -6-His-D-Trp-Ala-Trp-D-Phe-Lys-NH2.
In practicing the present invention, GHRP-6, as well as all other synthetic peptides in the same class of drugs that release GH by the same cellular mechanism as GHRP-6 referred to hereinafter as GHRP-6 or analogs thereof, will be used as diagnostic agents in children for differential diagnosis of growth hormone (GH) deficiency of various etiologies. Responses to GHRP-6 or analogs thereof will be compared with those resulting from administration of the endogenous GH releasing hormone (GHRH) and from co-administration of GHRH and GHRP-6 to better understand the cause of growth deficits in short statured children. Since GHRP-6 acts as a functional analog for a yet undefined GHRH co-factor or co-secretagogue, hyposensitivity to a provocative GHRH challenge could represent deficiency of that endogenous co-secretagogue (represented by GHRP-6) rather than down-regulation of pituitary receptor or deficits in GH synthesis and/or release. Such a child could have normal GHRH concentrations/secretion and a normal pituitary, but display poor GH secretion in the absence of the endogenous GHRP-6 analog.
On the other hand, this child would respond normally to a challenge dose of GHRP-6 because his/her complement of GHRH would be available.
In contrast, a child with GHRH deficiency, but having normal concentrations of GHRP-6 endogenous analog would respond normally to a provocative dose of GHRH, and poorly to GHRP-6 since the child's GHRH complement would be lacking. The paradox in this hypothesis is that a normal W094/00759 213~3a~ PCT/US93/05955 _ --7--response to a provocative challenge by a given GH
secretagogue (GHRH or GHRP-6 or analog thereof) will be observed for the peptide that is lacking or deficient in the slow-growing child.
Poor responses to individually administered GHRH and GHRP-6 would suggest a deficiency of both endogenous GH secretagogues, and/or a defect in pituitary GH
synthesis/release.
Thus, the present invention provides a new clinical application for GHRP-6 and other synthetic GH secretagogues that function by the same mechanism as GHRP-6. The invention is important because it not only provides a reliable method for identifying children with low GH
secretory capability, but also helps diagnose the etiology of GH deficiency and perhaps provide a key to appropriate treatment.
In practicing the present invention, children who are shorter than other children of a comparable age who have been identified as in need potentially of growth hormone or some agent that would stimulate growth hormone production would be monitored for the purpose of establishing a baseline level of growth hormone in the blood. Once baseline levels are established, the child is administered GHRH at a dose ranging from 100 ng/kg body weight to 100 mg/kg body weight. The GHRH peptide is administered and blood samples are monitored over a period of 120 minutes to determine whether the exogenous GHRH increased growth hormone levels.
After the effects of GHRH administration are determined, the child is administered GHRP-6 or an analog thereof at a dose of 100 ng/kg body 2l393~6 weight to 1 mg/kg body weight for one day. Blood samples are measured for any change in growth hormone levels. Additional administration of peptides may be made but a day of rest, i.e., a day during which neither peptide type is administered should intervene administration days. The dosage amount can be varied to determine optimal dosages. The changes, if any, in growth hormone levels to either or both of GHRH or GHRP-6 or analog thereof will provide an insight to the etiology of the short stature condition of the child.
In addition to GHRH, any growth hormone releasing compound can be utilized in the diagnostic procedure of the present invention.
However, GHRH is the preferred growth hormone releasing compound for use in the claimed invention. The growth hormone releasing compounds which may be used in practicing the present invention are any such compounds known to induce growth hormone (GH) secretion and include growth hormone releasing hormone (GHRH) (1-44) and analogs GHRH (1-40) and GHRH (1-29) thereof.
There are numerous growth hormone releasing compounds known in the art and any of these known compounds will be useful in practicing the present invention. U.S. Patent 4,622,312 provides an excellent description of GHRH and analog thereof, which can be used in the presently claimed invention. Reissue patent RE33,699 provides a summary of patents which teach growth hormone releasing compounds. The growth hormone releasing compounds taught in each of the following U.S. patents are suitable for invention. Reissue Patent No. RE 33,699 provides 9 2139~26 a summary of patents which teach growth hormone releasing compounds taught in each of the following U.S. patents are suitable for use in the method of the present invention:
U.S. RE 33,699 1-4 U.S. 4,517,181 2 U.S. 4,518,586 1-4 U.S. 4,528,190 1-2 10 U.S. 4,529,595 1-4 U.S. 4,562,175 1-2 U.S. 4,563,352 1-4 U.S. 4,585,756 1-2 U.S. 4,595,676 1-2 15 U.S. 4,605,643 1-2 U.S. 4,610,976 1-2 U.S. 4,617,149 1-4 U.S. 4,622,312 1-4 10 U.S. 4,626,523 1-2 20 U.S. 4,649,131 1-4 19 U.S. 4,710,382 1-2 U.S. 4,774,319 The above U.S. patents, and in particular the portions indicated above by column and line number, are incorporated herein by reference as teaching growth hormone releasing compounds that are useful in the practice of the presently claimed invention.
The term GHRP-6 and analogs thereof means GHRP-6 and any peptide compound that releases GH by the same cellular mechanism. In addition to GHRP-6, the pentapeptide Tyr-D-Trp-Gly-Phe-Met-NH2 (K. Cheng et al., Endocrinol.
1989; 124, 2791-2798) is a useful analog in the release of GH. Other compounds considered analogs of GHRP-6 for purposes of the present invention have been reported. For example, C.Y.
Bowers et al., Endocrinol. 1980; 106, 663 teaches in addition to Tyr-D-Trp-Gly-Phe-Met-NH2, compounds Tyr-D-Phe-Gly-Phe-Met-NH2 and Trp-D-W O 94/00759 PC~r/US93/05955 21393~ o-Phe-Pro-Phe-Met-COOH as being useful in the release of growth hormone, and GHRP-1 having the formula Ala-His-D-~-Nal-Ala-Trp-D-Phe-Lys-NH2 disclosed in the 74th Annual Meeting of the Endocrine Society, June 24-27, 1992, p. 182, San Antonio, Texas, is also useful in the release of growth hormone. Also, F.A. Momany et al., Endocrinol. 1981; 108, 31 teaches the following compounds as being useful in the release of growth hormone: Try-Ala-D-Trp-Phe-Met-NH2; Tyr-D-Trp-D-Trp-Phe-Met-NH2; Tyr-D-Trp-D-Trp-Phe-NH2;
Tyr-D-Trp-D-Trp-Phe-COOH; and D-Trp-D-Trp-Phe-NH2. Additionally, F.A. Momany et al., Endocrinol. 114, lS31 (1984) teaches the following compounds as being useful in the release of growth hormone: His-D-Trp-Ala-Trp-D-Phe-NH2; His-D-Trp-Ala-Trp-D-Phe-Lys-NH2; Tyr-D-Trp-Ala-Trp-D-Phe-NH2; His-D-Trp-Ala-Trp-D-Phe-Arg-NH2; and His-D-Trp-Ala-Trp-D-Phe-Lys-COOH.
All of these compounds are useful in the diagnostic procedure of the present invention.
The growth hormone levels in the blood of the child can be measured by any well known procedures, e.g., using an immunoradiometric assay as described by C.Y. Bowers et al., J. Clin Endocrinol. Metab 1990; 70, 975-982 or any other contemporary, scientifically accepted method.
Once the short-statured child is diagnosed as having either a deficiency in GHRH
or GHRP-6 the appropriate replacement therapy can ensue whereby either a growth hormone releasing compound or a GHRP-6 or analog thereof or a combination of both GH secretagogues is administered to the child.
Claims (15)
1. A method for measuring the effect of a growth hormone releasing compound and GHRP-6 or a peptide which causes release of growth hormone by the same cellular mechanism as GHRP-6 on the blood levels of growth hormone in a child of short stature which comprises the steps of:
(a) establishing a baseline level of growth hormone in the blood of said child;
(b) administering an amount of growth hormone releasing compound known to be effective to cause an increase in growth hormone levels in the blood;
(c) administering an amount of GHRP-6, or a peptide which causes release of growth hormone by the same cellular mechanism as GHRP-6, known to be effective to cause an increase in growth hormone levels in the blood;
(d) administering a combination of GHRH
and GHRP-6 or a peptide which causes release of growth hormone by the same cellular mechanism as GHRP-6 in amounts known to be effective to cause an increase in growth hormone levels in the blood; and (e) measuring levels of growth hormone in the blood after each of steps (b), (c) and (d).
(a) establishing a baseline level of growth hormone in the blood of said child;
(b) administering an amount of growth hormone releasing compound known to be effective to cause an increase in growth hormone levels in the blood;
(c) administering an amount of GHRP-6, or a peptide which causes release of growth hormone by the same cellular mechanism as GHRP-6, known to be effective to cause an increase in growth hormone levels in the blood;
(d) administering a combination of GHRH
and GHRP-6 or a peptide which causes release of growth hormone by the same cellular mechanism as GHRP-6 in amounts known to be effective to cause an increase in growth hormone levels in the blood; and (e) measuring levels of growth hormone in the blood after each of steps (b), (c) and (d).
2. The method of claim 1 wherein the growth hormone releasing compound is growth hormone releasing hormone.
3. The method of claim 2 wherein the GHRP-6 or analog thereof is selected from GHRP-6, GHRP-1, or one of the following peptides:
Tyr-D-Trp-Gly-Phe-Met-NH2;
Tyr-D-Phe-Gly-Phe-Met-NH2;
Trp-D-Phe-Pro-Phe-Met-COOH;
Tyr-Ala-D-Trp-Phe-Met-NH2;
Tyr-D-Trp-D-Trp-Phe-Met-NH2;
Tyr-D-Trp-D-Trp-Phe-NH2;
Tyr-D-Trp-D-Trp-Phe-COOH;
D-Trp-D-Trp-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-Lys-NH2;
Tyr-D-Trp-Ala-Trp-D-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-Arg-NH2;
His-D-Trp-D-Trp-Ala-Trp-D-Phe-Lys-COOH.
Tyr-D-Trp-Gly-Phe-Met-NH2;
Tyr-D-Phe-Gly-Phe-Met-NH2;
Trp-D-Phe-Pro-Phe-Met-COOH;
Tyr-Ala-D-Trp-Phe-Met-NH2;
Tyr-D-Trp-D-Trp-Phe-Met-NH2;
Tyr-D-Trp-D-Trp-Phe-NH2;
Tyr-D-Trp-D-Trp-Phe-COOH;
D-Trp-D-Trp-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-Lys-NH2;
Tyr-D-Trp-Ala-Trp-D-Phe-NH2;
His-D-Trp-Ala-Trp-D-Phe-Arg-NH2;
His-D-Trp-D-Trp-Ala-Trp-D-Phe-Lys-COOH.
4. The method of claim 1 wherein the amount of growth hormone releasing compound administered is 100 ng/kg-100 mg/kg of body weight once daily.
5. The method of claim 4 wherein the amount of GHRP-6 or a peptide which causes release of growth hormone by the same cellular mechanism administered is 100 ng/kg-1 mg/kg of body weight once daily.
6. The method of claim 5 wherein the growth hormone releasing compound is administered first.
7. The method of claim 5 wherein the growth hormone releasing compound is administered second.
8. The method of claim 1 wherein a combination of GHRH and GHRP-6 or a peptide which causes release of growth hormone by the same cellular mechanism is administered.
9. The method of claim 8 wherein the amount of GHRH administered is 100 ng/kg to 100 mg/kg of body weight and the amount of GHRP-6 or a peptide which acts by the same cellular mechanism as GHRP-6 is from 100 ng/kg to 1 mg/kg of body weight, each being administered once daily for one day.
10. The method of claim 1 wherein a day during which no peptide or hormone is administered intervenes each day on which a dosage is administered.
11. A method for diagnosing the etiology of short stature in a child which comprises administering sequentially an agent which is a growth hormone releasing compound and an agent which is GHRP-6 or a peptide which causes growth hormone release by the same cellular mechanism, and a combination of each said agent, each of said agents being administered in a quantity known to be effective in increasing blood levels of growth hormone and measuring the effects each agent has either alone or in combination on the growth hormone levels in the blood of said child.
12. The method of claim 11 wherein a baseline level of growth hormone in the blood is established for the child prior to the diagnostic procedure.
13. The method of claim 12 wherein the growth hormone releasing compound is GHRH.
14. The method of claim 13 wherein the GHRP-6 or peptide which causes growth hormone release by the same cellular mechanism is GHRP-6.
15. The method of claim 14 wherein a day during which neither agent is administered intervenes the days on which dosing occurs.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US90576092A | 1992-06-29 | 1992-06-29 | |
| US905,760 | 1992-06-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2139326A1 true CA2139326A1 (en) | 1994-01-06 |
Family
ID=25421421
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2139326 Abandoned CA2139326A1 (en) | 1992-06-29 | 1993-06-22 | Diagnostic procedure for evaluating short stature etiology |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0650597A4 (en) |
| CA (1) | CA2139326A1 (en) |
| WO (1) | WO1994000759A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5811074A (en) * | 1992-06-29 | 1998-09-22 | University Of South Florida | Method of diagnosing pituitary dependent growth hormone deficiency |
| WO1996029002A1 (en) * | 1995-03-17 | 1996-09-26 | University Of South Florida | Method of diagnosing pituitary dependent growth hormone deficiency |
| CU23016A1 (en) * | 2002-01-24 | 2005-01-25 | Ct Ingenieria Genetica Biotech | METHOD FOR THE STIMULATION OF THE GROWTH AND RESYMULATION FOR THE STIMULATION OF THE GROWTH AND RESISTANCE TO DISEASES IN AQUATIC ORGANISMS AND FSTENCE TO DISEASES IN AQUATIC ORGANISMS AND VETERINARY FORMULATION VETERINARY ORMULATION |
| US20130095122A1 (en) * | 2010-03-17 | 2013-04-18 | Anja Katrin Bosserhoff | Peptides or Antibodies Which Bind to Melanoma Inhibitory Activity (MIA) Protein |
| PL3939590T3 (en) * | 2015-09-21 | 2024-03-25 | Lumos Pharma, Inc. | Detecting and treating growth hormone deficiency |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4622312A (en) * | 1984-09-24 | 1986-11-11 | Hoffmann-La Roche Inc. | Growth hormone releasing factor analogs |
| US5246920A (en) * | 1992-06-15 | 1993-09-21 | University Of South Florida | Treatment of hyperprolactinemia |
-
1993
- 1993-06-22 EP EP93916678A patent/EP0650597A4/en not_active Withdrawn
- 1993-06-22 WO PCT/US1993/005955 patent/WO1994000759A1/en not_active Application Discontinuation
- 1993-06-22 CA CA 2139326 patent/CA2139326A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| EP0650597A4 (en) | 1996-12-18 |
| WO1994000759A1 (en) | 1994-01-06 |
| EP0650597A1 (en) | 1995-05-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Kaye et al. | Altered cerebrospinal fluid neuropeptide Y and peptide YY immunoreactivity in anorexia and bulimia nervosa | |
| Huhn et al. | Twenty-four-hour growth hormone (GH)-releasing peptide (GHRP) infusion enhances pulsatile GH secretion and specifically attenuates the response to a subsequent GHRP bolus. | |
| Chapman et al. | Stimulation of the growth hormone (GH)-insulin-like growth factor I axis by daily oral administration of a GH secretogogue (MK-677) in healthy elderly subjects | |
| Corpas et al. | Growth hormone (GH)-releasing hormone-(1-29) twice daily reverses the decreased GH and insulin-like growth factor-I levels in old men | |
| Liddle et al. | Cholecystokinin bioactivity in human plasma. Molecular forms, responses to feeding, and relationship to gallbladder contraction. | |
| Bearn et al. | Neuroendocrine responses to d-fenfluramine and insulin-induced hypoglycemia in chronic fatigue syndrome | |
| US8008024B2 (en) | Methods, products and treatments for diabetes | |
| EP1984744B1 (en) | Methods and kits to diagnose growth hormone deficiency | |
| Allain et al. | Changes in growth hormone, insulin, insulinlike growth factors (IGFs), and IGF-binding protein-1 in chronic fatigue syndrome | |
| ROSE et al. | Hypothyroidism and deficiency of the nocturnal thyrotropin surge in children with hypothalamic pituitary disorders | |
| Sato et al. | Effect of VIP on sweat secretion and cAMP accumulation in isolated simian eccrine glands | |
| Ranke | Diagnosis of growth hormone deficiency and growth hormone stimulation tests | |
| Alster et al. | The growth hormone (GH) response to GH-releasing peptide (His-DTrp-Ala-Trp-DPhe-Lys-NH2), GH-releasing hormone, and thyrotropin-releasing hormone in acromegaly | |
| Robertson et al. | Prolactin response to morphine in depression | |
| CA2139326A1 (en) | Diagnostic procedure for evaluating short stature etiology | |
| Ho et al. | Defining growth hormone deficiency in adults | |
| Korbonits et al. | Hexarelin as a test of pituitary reserve in patients with pituitary disease | |
| Facchinetti et al. | Neuroendocrine evaluation of central opiate activity in primary headache disorders | |
| Lesem et al. | Measurement of CSF dynorphin A 1–8 immunoreactivity in anorexia nervosa and normal-weight bulimia | |
| US5811074A (en) | Method of diagnosing pituitary dependent growth hormone deficiency | |
| D'Alessio et al. | Fasting and postprandial concentrations of somatostatin-28 and somatostatin-14 in type II diabetes in men | |
| Popovic et al. | The effectiveness of arginine+ GHRH test compared with GHRH+ GHRP‐6 test in diagnosing growth hormone deficiency in adults | |
| Pozo et al. | Growth hormone secretion in children with normal variants of short stature | |
| Tan et al. | Low renin essential hypertension: failure to demonstrate excess 11-deoxycorticosterone production | |
| Frohman et al. | Ectopic GRH syndromes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |