CA2293504A1 - Use of leptin antagonists for the treatment of diabetes - Google Patents
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- C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
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- A61P3/08—Drugs for disorders of the metabolism for glucose homeostasis
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- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
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- A61P3/08—Drugs for disorders of the metabolism for glucose homeostasis
- A61P3/10—Drugs for disorders of the metabolism for glucose homeostasis for hyperglycaemia, e.g. antidiabetics
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Abstract
The use of an antagonist of leptin for the manufacture of a medicament for the treatment of disorders resulting from deficiencies in insulin secretion, hyperglycaemia and insulin resistance.
Description
WO 98/55139 PCTlEP97/02240 USE OF LEPTIN ANTAGOMSTS FOR TIC TREATMIaVVT OF DIABETES
The invention relates to a novel use, in particular a use for the treatment of diabetes and complications thereof.
Non-insulin-dependent diabetes (NIDDM) is known to be caused by insulin resistance (particularly in skeletal muscle, adipose tissue and liver) and an inadequate insulin secretion from the beta-cells of the Islets of Langerhans in the pancreas. Thus, despite hyperinsulinaemia there is insufficient insulin to compensate for the insulin resistance and to maintain blood glucose in the desirable range.
Pelleymounter et al (Science, 1995, 269, 540-543) have reported that the ob polypeptide or "leptin" lowers both plasma insulin and glucose levels in the genetically obese oblob mouse.
United Kingdom patent application, Publication Number 2292382 relates inter alia to polypeptides, OB polypeptides, and antagonists thereof and their use for modulating bodyweight. The disclosures of GB 2292382 are incorporated herein by reference.
We have now shown that recombinant leptin directly inhibits insulin release from both isolated islets and the perfused pancreas of the oblob mouse. An antagonist of leptin is therefore indicated to be of value in enhancing insulin secretion and thereby assisting in the control of blood glucose levels. We have further shown that leptin inhibits basal and insulin-stimulated glycogen synthesis in isolated soleus muscle of oblob mice.
An antagonist of leptin is therefore also indicated to be of value in enhancing glucose utilisation and the action of insulin to enhance glucose utilisation.
Antagonists are therefore indicated to be of direct use in the treatment of disorders resulting from deficiencies in insulin secretion and action and of hyperglycaemia, such as non-insulin-dependent diabetes. Moreover, since hyperglycaemia is believed to lead to many of the long term complications of diabetes, an antagonist which enhances insulin secretion and assists in blood glucose control, may be useful in the treatment of diabetic complications, such as retinopathy, nephropathy and angiopathy.
Accordingly, the invention provides the use of an antagonist of leptin for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
In a further aspect, there is provided the use of an antagonist of leptin for the maunfacture of a medicament for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
Suitable antagonists of leptin are as disclosed in GB2292382 and may be prepared according to methods disclosed therein.
Particular antagonists include protein antagonists.
Particular antagonists include non-protein antagonists, especially small organic molecule antagonists.
The present invention also extends to a method for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM), in a human or non-human mammal, which method 45 comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
The present invention also extends to a pharmaceutical composition comprising an antagonist of leptin, or a pharmaceutically acceptable derivative thereof, and a pharmaceutically acceptable carrier.
50 Particular compositions of the invention are those used for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
Suitable pharmaceutically acceptable Garners are as dictated by conventional practice such as those disclosed in GB2292382 or in International Patent Application, 55 Publication Number WO 94/01420.
The compositions of the invention are prepared according to conventional practice, such as described in the above mentioned patent applications The dosages of the antagonists may be determined according to conventional methodology such as those described in the above mentioned patent applications.
60 The following is a brief description of the figures (Figures 1-S and Table 1) of the application:
Figure 1 and Table 1 show the effect of Ieptin (100nM) on basal insulin secretion from the perfused pancreas of ob mice;
Figure 2 shows the effect of ieptin (100 nmol/1) on glucose stimulated (16.7 mmoUl) 65 insulin secretion from ob/ob islets;
Figure 3 shows the dose - dependency of inhibitory effects of recombinant leptin on glucose-stimulated (16.7 mmol/1) insulin secretion from isolated pancreatic islets of ob/ob mice;
Figure 4 shows the effect of leptin on glycogen synthesis in isolated soleus muscle of 70 ob/ob mice; and Figure 5 shows the effect of leptin on the glycogen synthesis in isolated soleus muscle of ob/ob mice.
Lee et al (Nature, 1995, 379, 632-635) have shown that there are a number of forms of the leptin receptor. If the islet receptors) differs in nature or proportions to that 75 in other tissues, an especially useful antagonist would be one that antagonizes the action of leptin at the islet and/or skeletal muscle receptor, but does not antagonize other leptin receptors (e.g. in the hypothalamus) and thereby exacerbate insulin resistance.
Mutations in the mouse ob gene (J. Hered. 41, 317-318 ) 1950)) and the db gene (Science 153, 1127-1128 (1966)) result in obesity and non-insulin dependent diabetes.
80 The ob gene product, leptin, is expressed exclusively in adipose tissue (Nature (Lond.), 372, 425-432 (1994)) and it has been demonstrated that daily injections of recombinant leptin inhibits food intake and reduces body weight and fat-mass in ob/ob mice (Science 269, 543-546 (1995); Science 269, 540-543 (1995); Science 269, 546-549 (1995)). Such treatment also results in a reduction in the hyperinsulinaemia (Science 269, 85 (1995)). Recently, the gene that codes for the receptor for the ob-gene has been identified - (Cell 83, 1263-1271 (1995)). The leptin receptor has several alternatively spliced variants. One of these spliced variants is expressed at a high level in hypothalamus, and is believed to be the functional receptor in the regulation of energy balance.
It is abnormally spliced in C57B1/KSJ db/db mice (Nature (Loud.) 379, 622-635 (1996); Cell 90 84, 491-495 (1996); Science 271, 994-996 (1996)) so that the cytoplasmic region is missing, leading to defective signal transduction. We now report that, in addition to hypothalamus, the predicted functional leptin receptor ob-Rb, is expressed in several tissues, including pancreatic islets, in ob/ob mice. Furthermore, recombinant leptin inhibits directly insulin release from both isolated islets and the perfused pancreas of the 95 ob/ob mouse, and it inhibits basal and insulin-stimulated glycogen synthesis in isolated soleus muscle of oblob mice, demonstrating that leptin has both central and peripheral actions.
The diabetic (db) gene product in mice has been identified as the receptor for leptin. At least six alternatively spliced forms of the leptin message have been identified 100 (Nature (Loncl ) 379, 622-635 (1996)). One of these, Ob-Rb, has an extensive intracellular region containing a Box 2 sequence motif, which is required for the binding of JAK
protein kinases and is believed to encode the functional receptor. Short antisense oligodeoxynucleotide probes (Trayhurn et al, Biochem. Soc. Traps. Vol 23 page 4945, 1995) 30-34 mers, were designed to hybridise with different domains in the mouse leptin i OS receptor mRNA sequence and used to detect either expression of all transcripts of the leptin-receptor or to detect solely the leptin receptor long-form, Ob-Rb. Each oligonucleotide probe sequence was unique to the leptin receptor and had no significant homology to any other known sequence.
Expression in lean +/+ mice of total leptin receptor mRNA was detected in 110 hypothalamus, kidneys, lung, liver, whole pancreas, brain, soleus muscle and spleen but not in white adipose tissue, pituitary or heart. Total leptin receptor mRNA, standardised to poly(A) mRNA levels was over-expressed in ob/ob mice relative to the lean littermates. However, there were tissue specific differences in overexpression. Thus, hypothalamus which shows the highest level of expression in lean mice was only 2-fold 115 over-expressed in ob/ob mice. In kidney, total leptin mRNA was over-expressed 4-fold but in some other tissues that had low expression of total leptin mRNA in lean mice, total leptin mRNA was over-expressed by up to 10-fold in ob/ob mice.
Northern blot analysis of hypothalamus probed with a 34-mer corresponding to bases 3329-3363, which are part of the intracellular loop present only in the long-form of 120 this leptin receptor Ob-Rb, gave a single sharp band. This contrasted with the multiple bands when the blot was probed with the 33-mer corresponding to bases 1877-1910, which is a sequence common to all the known splice variants of the leptin receptor.
Molecular weight markers indicated that the 34-mer hybridised to a mRNA
fragment of approximately 3400 b.p. consistent with the putative functional leptin receptor. This was 125 found to be expressed at a high level in hypothalamus, in agreement with the recent studies of Lee et al (Nature (Loud.) 379, 622-635 (1996)).
- Furthermore, the hypothalami from ob/ob mice showed 2-fold over-expression relative to the +/+ mice. The Ob-Rb leptin receptor is also present (and over-expressed relative to lean +/+ mice) in liver, kidney and lung but not in whole brain, heart, soleus muscle or 130 pituitary. The finding of relative over-expression of the Ob-Rb leptin in ob/ob mice relative to lean +/+ mice is consistent with the findings of several workers (Science 269, 540-543 (1995); Proc. Natl, Acad. Sci., USA 93, 1726-1730 (1996)) that recombinant leptin is more effective in reducing food intake and body weight in the ob/ob mice. It also raises the possibility that leptin regulates the expression of its receptor. This could 135 result in leptin resistant states and could explain the relative lack of activity of recombinant leptin in dietary induced obesity (Science 269, 540-543 (1995)).
Using the slot-blot technique, no expression of the long-form of the leptin receptor was detected in whole pancreata from either lean +/+ or ob/ob mice. However, a strong signal was obtained using mRNA from ob/ob mouse pancreatic islets.
140 Previous studies have demonstrated that daily intraperitoneal injections of recombinant leptin for 28 days produced a dose-dependent significant reduction in serum insulin and blood glucose in ob/ob mice but not in lean mice (Science 269, 540-(1995)). Given the high expression of the long-form of the leptin receptor, which is the putative functional receptor, in pancreatic islets from ob/ob mice, we decided to examine 145 the functional response on insulin secretion using the ob/ob mouse perfused pancreas (Fig. l , Table 1 ).
Leptin ( 1 OOnM) produced an immediate reduction in the insulin release from the isolated pancreas.
The action of leptin in the perfused pancreas preparation could be either direct on 1 SO islets or via the release of a further mediator from the vasculature. To clarify this, the effect of leptin on insulin release from ob/ob mouse isolated pancreatic islets was determined. Leptin (100nM) completely inhibited the stimulatory effect of 16.7mM
glucose on insulin release in islets isolated from overnight-fasted mice (Fig.2). The inhibitory effect of leptin was dose-related over the range 1-100nM (Fig. 3).
Also leptin 155 (10 nm) inhibited glucose-stimulated insulin secretion by islets from wild-type mice, but leptin ( 100 nM) had no effect on insulin secretion by islets from ob/ob mice.
To evaluate the possibility that leptin might directly inhibit glucose uptake and insulin action, [14C]-glucose incorporation into glycogen was measured in isolated intact soleus muscles, from ob/ob mice, weighing 4-6mg using the method of Challiss et al.
160 (Biochemical Pharmacology, 1988, 37, 947-950). Recombinant marine leptin at 100nM
inhibited glycogen synthesis in soleus muscle (Fig 4), with 35% inhibition at basal (P<
0.01 ), and 28%, 30% and 45% at low insulin concentrations ( 10, 50 and 1 OOuU/ml respectively, P< 0.05). The maximal response to insulin (10,000uU/ml) was not significantly affected by leptin. The effects of lower concentrations of leptin ( 1 and 165 lOnM) were examined in the absence of insulin and in the presence of 100uU/ml insulin.
l OnM leptin caused significant inhibition of both basal and insulin-stimulated glycogen synthesis (32% and 35% respectively; P< 0.05), whereas 1nM leptin did not have a significant effect (Fig 5).
Obesity is the commonest nutritional disorder in Western Society and in many 170 developing countries. It is strongly associated with non-insulin dependent diabetes. The basis of this association has largely been assumed to relate to the increase in insulin resistance that occurs with developing adiposity. Insulin resistance might be expected to result in glucose intolerance but it is commonly believed that the development of non-insulin dependent diabetes requires the additional independent development of a 175 pancreatic lesion.
Initial studies using infusion of recombinant leptin to ob/ob mice and lean littermates suggested that the primary action of leptin was to control appetite possibly through a suppression of central NPY release (Nature (Loud.) 337, 530-532 (1995)).
However, a more recent study which included a group of ob/ob mice that consumed the 180 same amount of food as leptin infused mice, demonstrated that leptin had significant metabolic actions (Proc. Natl, Acad. Sci., USA 93, 1726-1730 (1996)). The infusion of leptin to ob/ob mice resulted in a significantly lower body weight and fat pad weight relative to pair-fed mice. However, the most dramatic difference between the mice infused with leptin and the pair-fed animals was in the serum insulin concentration. Pair-185 feeding reduced the insulin concentration from 30.6 ~ 6.2 mg/ml to 14.2 t 4.2 mg/ml. In the mice infused with leptin, the insulin concentration 0.09 ~ 0.08 ng/ml was not significantly different from lean animals (Proc. Natl, Acad. Sci., USA 93, (1996)). The present study demonstrates that the leptin receptor spliced variant that encodes the functional receptor is present in pancreatic islets of ob/ob mice, and that 190 leptin will directly inhibit basal insulin secretion in the perfused pancreas and glucose stimulated insulin release by isolated islets of the ob/ob mice. These data suggest for the first time that leptin over-production following excess adiposity may directly modify insulin secretion and could be involved in the development of the diabetic syndrome.
These data further suggest that leptin overproduction associated with obesity may be one 195 of a number of factors responsible for inducing insulin resistance in obesity.
Accordingly, in a further particular aspect the present invention provides the use of an antagonist of leptin for the treatment of insulin resistance, especially that associated with obesity.
Further provided is the use of an antagonist of leptin for the maunfacture of a 200 medicament for the treatment of insulin resistance, especially that associated with obesity.
Also provided is a method for the treatment of of insulin resistance, especially that associated with obesity, in a human or non-human mammal, which method comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
205 A further particular pharmaceutical composition of the invention is therefore a pharmaceutical composition useful for the treatment of of insulin resistance, especially that associated with obesity.
The invention relates to a novel use, in particular a use for the treatment of diabetes and complications thereof.
Non-insulin-dependent diabetes (NIDDM) is known to be caused by insulin resistance (particularly in skeletal muscle, adipose tissue and liver) and an inadequate insulin secretion from the beta-cells of the Islets of Langerhans in the pancreas. Thus, despite hyperinsulinaemia there is insufficient insulin to compensate for the insulin resistance and to maintain blood glucose in the desirable range.
Pelleymounter et al (Science, 1995, 269, 540-543) have reported that the ob polypeptide or "leptin" lowers both plasma insulin and glucose levels in the genetically obese oblob mouse.
United Kingdom patent application, Publication Number 2292382 relates inter alia to polypeptides, OB polypeptides, and antagonists thereof and their use for modulating bodyweight. The disclosures of GB 2292382 are incorporated herein by reference.
We have now shown that recombinant leptin directly inhibits insulin release from both isolated islets and the perfused pancreas of the oblob mouse. An antagonist of leptin is therefore indicated to be of value in enhancing insulin secretion and thereby assisting in the control of blood glucose levels. We have further shown that leptin inhibits basal and insulin-stimulated glycogen synthesis in isolated soleus muscle of oblob mice.
An antagonist of leptin is therefore also indicated to be of value in enhancing glucose utilisation and the action of insulin to enhance glucose utilisation.
Antagonists are therefore indicated to be of direct use in the treatment of disorders resulting from deficiencies in insulin secretion and action and of hyperglycaemia, such as non-insulin-dependent diabetes. Moreover, since hyperglycaemia is believed to lead to many of the long term complications of diabetes, an antagonist which enhances insulin secretion and assists in blood glucose control, may be useful in the treatment of diabetic complications, such as retinopathy, nephropathy and angiopathy.
Accordingly, the invention provides the use of an antagonist of leptin for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
In a further aspect, there is provided the use of an antagonist of leptin for the maunfacture of a medicament for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
Suitable antagonists of leptin are as disclosed in GB2292382 and may be prepared according to methods disclosed therein.
Particular antagonists include protein antagonists.
Particular antagonists include non-protein antagonists, especially small organic molecule antagonists.
The present invention also extends to a method for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM), in a human or non-human mammal, which method 45 comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
The present invention also extends to a pharmaceutical composition comprising an antagonist of leptin, or a pharmaceutically acceptable derivative thereof, and a pharmaceutically acceptable carrier.
50 Particular compositions of the invention are those used for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, such as non-insulin-dependent diabetes (NIDDM).
Suitable pharmaceutically acceptable Garners are as dictated by conventional practice such as those disclosed in GB2292382 or in International Patent Application, 55 Publication Number WO 94/01420.
The compositions of the invention are prepared according to conventional practice, such as described in the above mentioned patent applications The dosages of the antagonists may be determined according to conventional methodology such as those described in the above mentioned patent applications.
60 The following is a brief description of the figures (Figures 1-S and Table 1) of the application:
Figure 1 and Table 1 show the effect of Ieptin (100nM) on basal insulin secretion from the perfused pancreas of ob mice;
Figure 2 shows the effect of ieptin (100 nmol/1) on glucose stimulated (16.7 mmoUl) 65 insulin secretion from ob/ob islets;
Figure 3 shows the dose - dependency of inhibitory effects of recombinant leptin on glucose-stimulated (16.7 mmol/1) insulin secretion from isolated pancreatic islets of ob/ob mice;
Figure 4 shows the effect of leptin on glycogen synthesis in isolated soleus muscle of 70 ob/ob mice; and Figure 5 shows the effect of leptin on the glycogen synthesis in isolated soleus muscle of ob/ob mice.
Lee et al (Nature, 1995, 379, 632-635) have shown that there are a number of forms of the leptin receptor. If the islet receptors) differs in nature or proportions to that 75 in other tissues, an especially useful antagonist would be one that antagonizes the action of leptin at the islet and/or skeletal muscle receptor, but does not antagonize other leptin receptors (e.g. in the hypothalamus) and thereby exacerbate insulin resistance.
Mutations in the mouse ob gene (J. Hered. 41, 317-318 ) 1950)) and the db gene (Science 153, 1127-1128 (1966)) result in obesity and non-insulin dependent diabetes.
80 The ob gene product, leptin, is expressed exclusively in adipose tissue (Nature (Lond.), 372, 425-432 (1994)) and it has been demonstrated that daily injections of recombinant leptin inhibits food intake and reduces body weight and fat-mass in ob/ob mice (Science 269, 543-546 (1995); Science 269, 540-543 (1995); Science 269, 546-549 (1995)). Such treatment also results in a reduction in the hyperinsulinaemia (Science 269, 85 (1995)). Recently, the gene that codes for the receptor for the ob-gene has been identified - (Cell 83, 1263-1271 (1995)). The leptin receptor has several alternatively spliced variants. One of these spliced variants is expressed at a high level in hypothalamus, and is believed to be the functional receptor in the regulation of energy balance.
It is abnormally spliced in C57B1/KSJ db/db mice (Nature (Loud.) 379, 622-635 (1996); Cell 90 84, 491-495 (1996); Science 271, 994-996 (1996)) so that the cytoplasmic region is missing, leading to defective signal transduction. We now report that, in addition to hypothalamus, the predicted functional leptin receptor ob-Rb, is expressed in several tissues, including pancreatic islets, in ob/ob mice. Furthermore, recombinant leptin inhibits directly insulin release from both isolated islets and the perfused pancreas of the 95 ob/ob mouse, and it inhibits basal and insulin-stimulated glycogen synthesis in isolated soleus muscle of oblob mice, demonstrating that leptin has both central and peripheral actions.
The diabetic (db) gene product in mice has been identified as the receptor for leptin. At least six alternatively spliced forms of the leptin message have been identified 100 (Nature (Loncl ) 379, 622-635 (1996)). One of these, Ob-Rb, has an extensive intracellular region containing a Box 2 sequence motif, which is required for the binding of JAK
protein kinases and is believed to encode the functional receptor. Short antisense oligodeoxynucleotide probes (Trayhurn et al, Biochem. Soc. Traps. Vol 23 page 4945, 1995) 30-34 mers, were designed to hybridise with different domains in the mouse leptin i OS receptor mRNA sequence and used to detect either expression of all transcripts of the leptin-receptor or to detect solely the leptin receptor long-form, Ob-Rb. Each oligonucleotide probe sequence was unique to the leptin receptor and had no significant homology to any other known sequence.
Expression in lean +/+ mice of total leptin receptor mRNA was detected in 110 hypothalamus, kidneys, lung, liver, whole pancreas, brain, soleus muscle and spleen but not in white adipose tissue, pituitary or heart. Total leptin receptor mRNA, standardised to poly(A) mRNA levels was over-expressed in ob/ob mice relative to the lean littermates. However, there were tissue specific differences in overexpression. Thus, hypothalamus which shows the highest level of expression in lean mice was only 2-fold 115 over-expressed in ob/ob mice. In kidney, total leptin mRNA was over-expressed 4-fold but in some other tissues that had low expression of total leptin mRNA in lean mice, total leptin mRNA was over-expressed by up to 10-fold in ob/ob mice.
Northern blot analysis of hypothalamus probed with a 34-mer corresponding to bases 3329-3363, which are part of the intracellular loop present only in the long-form of 120 this leptin receptor Ob-Rb, gave a single sharp band. This contrasted with the multiple bands when the blot was probed with the 33-mer corresponding to bases 1877-1910, which is a sequence common to all the known splice variants of the leptin receptor.
Molecular weight markers indicated that the 34-mer hybridised to a mRNA
fragment of approximately 3400 b.p. consistent with the putative functional leptin receptor. This was 125 found to be expressed at a high level in hypothalamus, in agreement with the recent studies of Lee et al (Nature (Loud.) 379, 622-635 (1996)).
- Furthermore, the hypothalami from ob/ob mice showed 2-fold over-expression relative to the +/+ mice. The Ob-Rb leptin receptor is also present (and over-expressed relative to lean +/+ mice) in liver, kidney and lung but not in whole brain, heart, soleus muscle or 130 pituitary. The finding of relative over-expression of the Ob-Rb leptin in ob/ob mice relative to lean +/+ mice is consistent with the findings of several workers (Science 269, 540-543 (1995); Proc. Natl, Acad. Sci., USA 93, 1726-1730 (1996)) that recombinant leptin is more effective in reducing food intake and body weight in the ob/ob mice. It also raises the possibility that leptin regulates the expression of its receptor. This could 135 result in leptin resistant states and could explain the relative lack of activity of recombinant leptin in dietary induced obesity (Science 269, 540-543 (1995)).
Using the slot-blot technique, no expression of the long-form of the leptin receptor was detected in whole pancreata from either lean +/+ or ob/ob mice. However, a strong signal was obtained using mRNA from ob/ob mouse pancreatic islets.
140 Previous studies have demonstrated that daily intraperitoneal injections of recombinant leptin for 28 days produced a dose-dependent significant reduction in serum insulin and blood glucose in ob/ob mice but not in lean mice (Science 269, 540-(1995)). Given the high expression of the long-form of the leptin receptor, which is the putative functional receptor, in pancreatic islets from ob/ob mice, we decided to examine 145 the functional response on insulin secretion using the ob/ob mouse perfused pancreas (Fig. l , Table 1 ).
Leptin ( 1 OOnM) produced an immediate reduction in the insulin release from the isolated pancreas.
The action of leptin in the perfused pancreas preparation could be either direct on 1 SO islets or via the release of a further mediator from the vasculature. To clarify this, the effect of leptin on insulin release from ob/ob mouse isolated pancreatic islets was determined. Leptin (100nM) completely inhibited the stimulatory effect of 16.7mM
glucose on insulin release in islets isolated from overnight-fasted mice (Fig.2). The inhibitory effect of leptin was dose-related over the range 1-100nM (Fig. 3).
Also leptin 155 (10 nm) inhibited glucose-stimulated insulin secretion by islets from wild-type mice, but leptin ( 100 nM) had no effect on insulin secretion by islets from ob/ob mice.
To evaluate the possibility that leptin might directly inhibit glucose uptake and insulin action, [14C]-glucose incorporation into glycogen was measured in isolated intact soleus muscles, from ob/ob mice, weighing 4-6mg using the method of Challiss et al.
160 (Biochemical Pharmacology, 1988, 37, 947-950). Recombinant marine leptin at 100nM
inhibited glycogen synthesis in soleus muscle (Fig 4), with 35% inhibition at basal (P<
0.01 ), and 28%, 30% and 45% at low insulin concentrations ( 10, 50 and 1 OOuU/ml respectively, P< 0.05). The maximal response to insulin (10,000uU/ml) was not significantly affected by leptin. The effects of lower concentrations of leptin ( 1 and 165 lOnM) were examined in the absence of insulin and in the presence of 100uU/ml insulin.
l OnM leptin caused significant inhibition of both basal and insulin-stimulated glycogen synthesis (32% and 35% respectively; P< 0.05), whereas 1nM leptin did not have a significant effect (Fig 5).
Obesity is the commonest nutritional disorder in Western Society and in many 170 developing countries. It is strongly associated with non-insulin dependent diabetes. The basis of this association has largely been assumed to relate to the increase in insulin resistance that occurs with developing adiposity. Insulin resistance might be expected to result in glucose intolerance but it is commonly believed that the development of non-insulin dependent diabetes requires the additional independent development of a 175 pancreatic lesion.
Initial studies using infusion of recombinant leptin to ob/ob mice and lean littermates suggested that the primary action of leptin was to control appetite possibly through a suppression of central NPY release (Nature (Loud.) 337, 530-532 (1995)).
However, a more recent study which included a group of ob/ob mice that consumed the 180 same amount of food as leptin infused mice, demonstrated that leptin had significant metabolic actions (Proc. Natl, Acad. Sci., USA 93, 1726-1730 (1996)). The infusion of leptin to ob/ob mice resulted in a significantly lower body weight and fat pad weight relative to pair-fed mice. However, the most dramatic difference between the mice infused with leptin and the pair-fed animals was in the serum insulin concentration. Pair-185 feeding reduced the insulin concentration from 30.6 ~ 6.2 mg/ml to 14.2 t 4.2 mg/ml. In the mice infused with leptin, the insulin concentration 0.09 ~ 0.08 ng/ml was not significantly different from lean animals (Proc. Natl, Acad. Sci., USA 93, (1996)). The present study demonstrates that the leptin receptor spliced variant that encodes the functional receptor is present in pancreatic islets of ob/ob mice, and that 190 leptin will directly inhibit basal insulin secretion in the perfused pancreas and glucose stimulated insulin release by isolated islets of the ob/ob mice. These data suggest for the first time that leptin over-production following excess adiposity may directly modify insulin secretion and could be involved in the development of the diabetic syndrome.
These data further suggest that leptin overproduction associated with obesity may be one 195 of a number of factors responsible for inducing insulin resistance in obesity.
Accordingly, in a further particular aspect the present invention provides the use of an antagonist of leptin for the treatment of insulin resistance, especially that associated with obesity.
Further provided is the use of an antagonist of leptin for the maunfacture of a 200 medicament for the treatment of insulin resistance, especially that associated with obesity.
Also provided is a method for the treatment of of insulin resistance, especially that associated with obesity, in a human or non-human mammal, which method comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
205 A further particular pharmaceutical composition of the invention is therefore a pharmaceutical composition useful for the treatment of of insulin resistance, especially that associated with obesity.
WO 98/55139 PCTlEP97/02240 In addition to pancreatic islets, we have also detected the long-form of the leptin receptor in liver, kidney and lung. The functional effects of leptin in these tissues are at 210 present unknown. However, Levin et al (Proc. Natl, Acad. Sci., USA 93, (1996)) noted that hepatic glycogen content of liver was significantly reduced in leptin-infused ob/ob mice but not in pair-fed animals. Together with the current data these findings are suggestive that leptin might directly affect hepatic glycogen metabolism.
In summary, the present results present both molecular biology and functional 215 evidence for leptin having widespread peripheral metabolic activity as well as a central action on food intake.
The disclosures of the above mentioned references including patent applicatons GB2292382 and WO 94/01420 are incorporated herein by reference.
The following Figures and Table illustrate the invention but do not limit it in any 220 way.
In summary, the present results present both molecular biology and functional 215 evidence for leptin having widespread peripheral metabolic activity as well as a central action on food intake.
The disclosures of the above mentioned references including patent applicatons GB2292382 and WO 94/01420 are incorporated herein by reference.
The following Figures and Table illustrate the invention but do not limit it in any 220 way.
Table 1 Control Leptin AUC 0-l5min 0.20810.022 (4) 0.19010.028 (5) AUC 16-30min 0.19610.019 (4) 0.12810.019 (5)*
change 96.5111.3 (4) J 69.20.45 (5)*
0-l5min: Stabilization period I6-30min: treated period (PBS or Leptin) AUC: area under the curve Change: the means of 16-30min vs the means of 0-l~min Results are meanstSEM (n=4.5). *P<0.05 (un-paired test) _7_
change 96.5111.3 (4) J 69.20.45 (5)*
0-l5min: Stabilization period I6-30min: treated period (PBS or Leptin) AUC: area under the curve Change: the means of 16-30min vs the means of 0-l~min Results are meanstSEM (n=4.5). *P<0.05 (un-paired test) _7_
Claims (9)
1. The use of an antagonist of leptin for the manufacture of a medicament for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia.
2. A use according to claim 1, for the treatment of non-insulin-dependent diabetes (NIDDM).
3. The use of an antagonist of leptin for the manufacture of a medicament for the treatment of insulin resistance.
4. A use according to claim 3, for the treatment of insulin resistance associated with obesity.
5. A method for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, in a human or non-human mammal, which method comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
6. A method for the treatment of insulin resistance, which method comprises the administration to human or non-human mammal in need of such treatment, an effective, pharmaceutically acceptable, non-toxic amount of an antagonist of leptin.
7. A pharmaceutical composition for the treatment of disorders resulting from deficiencies in insulin secretion and of hyperglycaemia, comprising an antagonist of leptin, or a pharmaceutically acceptable derivative thereof, and a pharmaceutically acceptable carrier.
8. A pharmaceutical composition for the treatment of insulin resistance, comprising an antagonist of leptin, or a pharmaceutically acceptable derivative thereof, and a pharmaceutically acceptable carrier.
9. A use according to any one of claims 1 to 8, wherein the antagonist of leptin is a small organic molecule antagonist.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP1997/002240 WO1998055139A1 (en) | 1997-06-06 | 1997-06-06 | Use of leptin antagonists for the treatment of diabetes |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2293504A1 true CA2293504A1 (en) | 1998-12-10 |
Family
ID=8166613
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002293504A Abandoned CA2293504A1 (en) | 1997-06-06 | 1997-06-06 | Use of leptin antagonists for the treatment of diabetes |
Country Status (9)
| Country | Link |
|---|---|
| EP (1) | EP0986397A1 (en) |
| JP (1) | JP2002504102A (en) |
| KR (1) | KR20010013414A (en) |
| AU (1) | AU2951797A (en) |
| CA (1) | CA2293504A1 (en) |
| HU (1) | HUP0003428A3 (en) |
| IL (1) | IL133136A0 (en) |
| TR (1) | TR199902980T2 (en) |
| WO (1) | WO1998055139A1 (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7208572B2 (en) | 1998-08-21 | 2007-04-24 | Albany Medical College | Leptin-related peptides |
| US6777388B1 (en) | 1998-08-21 | 2004-08-17 | Clf Medical Technology Acceleration Program, Inc. | Leptin-related peptides |
| US20050272652A1 (en) | 1999-03-29 | 2005-12-08 | Gault Victor A | Peptide analogues of GIP for treatment of diabetes, insulin resistance and obesity |
| US8076288B2 (en) | 2004-02-11 | 2011-12-13 | Amylin Pharmaceuticals, Inc. | Hybrid polypeptides having glucose lowering activity |
| AU2005211755B2 (en) | 2004-02-11 | 2012-03-15 | Amylin Pharmaceuticals, Llc | Hybrid polypeptides with selectable properties |
| US8263545B2 (en) | 2005-02-11 | 2012-09-11 | Amylin Pharmaceuticals, Inc. | GIP analog and hybrid polypeptides with selectable properties |
| AU2006213607A1 (en) | 2005-02-11 | 2006-08-17 | Amylin Pharmaceuticals, Llc | GIP analog and hybrid polypeptides with selectable properties |
| AU2006279680B2 (en) | 2005-08-11 | 2012-12-06 | Amylin Pharmaceuticals, Llc | Hybrid polypeptides with selectable properties |
| EP2330125A3 (en) | 2005-08-11 | 2012-12-12 | Amylin Pharmaceuticals, Inc. | Hybrid polypeptides with selectable properties |
| US8497240B2 (en) | 2006-08-17 | 2013-07-30 | Amylin Pharmaceuticals, Llc | DPP-IV resistant GIP hybrid polypeptides with selectable properties |
| EP2416797A4 (en) | 2009-04-10 | 2013-04-24 | Amylin Pharmaceuticals Llc | Amylin agonist compounds for estrogen-deficient mammals |
| WO2012050925A2 (en) | 2010-09-28 | 2012-04-19 | Amylin Pharmaceuticals, Inc. | Highly soluble leptins |
| PT2729160T (en) | 2011-07-08 | 2019-07-08 | Aegerion Pharmaceuticals Inc | Engineered polypeptides having enhanced duration of action and reduced immunogenicity |
| LT2900230T (en) | 2012-09-27 | 2019-01-10 | The Children`S Medical Center Corporation | Compounds for the treatment of obesity and methods of use thereof |
| LT3074033T (en) | 2013-11-26 | 2019-02-25 | The Children`S Medical Center Corporation | Compounds for the treatment of obesity and methods of use thereof |
| WO2015153933A1 (en) | 2014-04-03 | 2015-10-08 | The Children's Medical Center Corporation | Hsp90 inhibitors for the treatment of obesity and methods of use thereof |
| FI3509624T3 (en) | 2016-09-12 | 2023-10-18 | Amryt Pharmaceuticals Inc | Methods of detecting anti-leptin neutralizing antibodies |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6309853B1 (en) * | 1994-08-17 | 2001-10-30 | The Rockfeller University | Modulators of body weight, corresponding nucleic acids and proteins, and diagnostic and therapeutic uses thereof |
| WO1997002004A2 (en) * | 1995-06-30 | 1997-01-23 | Eli Lilly And Company | Methods for treating diabetes |
-
1997
- 1997-06-06 CA CA002293504A patent/CA2293504A1/en not_active Abandoned
- 1997-06-06 KR KR19997011415A patent/KR20010013414A/en not_active Application Discontinuation
- 1997-06-06 IL IL13313697A patent/IL133136A0/en unknown
- 1997-06-06 EP EP97923840A patent/EP0986397A1/en not_active Withdrawn
- 1997-06-06 AU AU29517/97A patent/AU2951797A/en not_active Abandoned
- 1997-06-06 TR TR1999/02980T patent/TR199902980T2/en unknown
- 1997-06-06 WO PCT/EP1997/002240 patent/WO1998055139A1/en not_active Application Discontinuation
- 1997-06-06 JP JP50135299A patent/JP2002504102A/en active Pending
- 1997-06-06 HU HU0003428A patent/HUP0003428A3/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| JP2002504102A (en) | 2002-02-05 |
| TR199902980T2 (en) | 2000-05-22 |
| AU2951797A (en) | 1998-12-21 |
| HUP0003428A3 (en) | 2001-12-28 |
| EP0986397A1 (en) | 2000-03-22 |
| KR20010013414A (en) | 2001-02-26 |
| IL133136A0 (en) | 2001-03-19 |
| HUP0003428A2 (en) | 2001-05-28 |
| WO1998055139A1 (en) | 1998-12-10 |
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