Patent Application
20110293562
The invention is related to the use of cardiotrophin-1 (CT-1) for the treatment of obesity and associated disorders: hyperglycaemias, insulin resistance, development of type 2 diabetes and dyslipemias and given its anorexigenic role, fat oxidation stimulant, hypoglycaemic, sensitizing agent of the action of insulin on a skeletal muscle level and inhibitor of the intestinal transport of glucose by enterocytes.
Obesity is a serious public-health problem which has reached epidemic proportions in many developed countries (Bellanger and Bray, 2005, J The State Med Soc; 157:S42-49; quiz 49). The increased food intake, unhealthy diet habits, and sedentary lifestyle in our developed countries have undoubtedly contributed to the obesity boom (Stein and Colditz et al., 2004, J. Clin. Endocrinol. Metab. 89:2522-5). Many studies have shown that the alarming increase in the prevalence of obesity and its metabolic disorders is associated to insulin resistance, dyslipemias, and eventual failure of the beta cells in the pancreas, leading inexorably to type 2 diabetes with all the consequences this disease entails (Rana et al., 2007, Diabetes Obes. Metab., 9:218-232).
Current treatments for obesity are the following: i) Xenical (Orlistat) is an inhibitor of gastrointestinal lipase which produces a moderate weight loss but has the main problem of adverse gastrointestinal effects, including colon cancer. ii) Sibutramine is a monoamine-capturing inhibitor which produces a greater weight loss than the previous treatment, but is associated to an increase in blood pressure and an increase in cardiac output. iii) Finally, use of Rimonabant, which is approved in Europe (though not by the FDA), and is an endocannabinoid receptor antagonist, but which has the problem of causing alterations in emotional behaviour such as depression, for which reason it has been withdrawn from the market.
As regards current treatments for insulin resistance, generally thiazolidinediones (TZDs) are used in combination with other therapies. The problem with these drugs is weight gain, especially when administered together with insulin. From all of this it can be gathered that an agent capable of sensitizing or increasing insulin action in addition to reducing body weight may be of great interest in these pathologies. Moreover, treatments with peripheral actions such as intestinal glucose inhibition could be of great interest in obesity and diabetes mellitus.
The discovery of leptin at the end of 1994 opened up new horizons in the study of the factors secreted by the adipocyte in regulating energy balance. This protein is mainly produced and secreted by the adipocyte proportionally to the fat mass. This protein was identified as a central nervous system modulator for appetite regulation, in addition to peripheral actions increasing fat oxidation and glucose capture by muscles. However, it was soon observed that obesity was related to high leptin levels and that endogenous leptin was not effective, for which reason the majority of obese humans and rodents were leptin-resistant, therefore this therapeutic weapon would be limited to individuals with disorders that result in leptin deficiency (a low percentage of obese people).
Since leptin is structurally similar to the cytokines of the gp-130 family and the leptin receptor (LRb) is structurally similar to the gp130 cytokine receptor known as gp-130Rbeta, the capacity of another member of the gp130 cytokine family, in particular CNTF, as a possible therapeutic agent for the treatment of obesity in order to overcome the problem of leptin resistance observed in obese individuals has been studied.
It is known that the CNTF cytokine has a possible therapeutic potential in mice suffering from obesity, insulin resistance, and a fatty liver, as it improves all these parameters (Sleeman et al., 2003, Proc Natl Acad. Sci. USA, 100:14297-14302). The anorexigenic role of CNTF (Stephens T W et al., 1995), the capacity of this cytokine to revert insulin resistance through the AMPK activation capacity (Watt et al., 2006, Nat. Med., 12:541-548) as well as its capacity to stimulate glucose capture by muscles
(Steinberg et al., 2009, Diabetes, Epub Jan. 9, 2009) have been described, which has led to proposing this cytokine as a possible treatment for obesity and related diseases (Ahima et al., 2006, Nat. Med., 12:511-512). Nevertheless, the use of this cytokine as a therapeutic agent is limited by the low expression of the CNTFRa receptor in adipose and muscle tissue, by the high number of CNS, and by the production of anti-CNTF antibodies. Clinical trials with this cytokine in patients weighing approximately 114 kg for 84 days at doses of 1-2 micrograms/kg led to the loss of 3-4 kg. Whilst these results seemed promising, nausea appeared in patients with high CNTF doses, and they eventually gained weight due to the development of anti-CNTF antibodies (Ettinger M.P. et al., JAMA, 2003, 289:1826-32).
Therefore, there is a need in the state of the art for agents useful for the treatment of obesity which do not have the drawbacks of the gp130-based ligands known to date.
In a first aspect, the invention is related to a compound that induces cardiotrophin 1 (CT-1) activity for the treatment of a metabolic disease, as well as to the use of a compound that induces cardiotrophin 1 (CT-1) activity for the preparation of a drug for the treatment of a metabolic disease.
In another aspect, the invention is related to a cosmetic method for the treatment of obesity, which comprises administering the patient a pharmaceutically active quantity of a compound that induces cardiotrophin 1 activity.
In another aspect, the invention is related to a composition that comprises, together or separately, a compound that induces cardiotrophin activity and an anti-diabetic compound. In successive aspects, the invention is related to a composition in accordance with the invention for the treatment of a metabolic disease, wherein the composition is administered simultaneously, separately or sequentially, as well as to the use of a composition in accordance with the invention for the preparation of a drug for the treatment of a metabolic disease, wherein the composition is administered simultaneously, separately or sequentially.
In another aspect, the invention is related to a cosmetic method for the treatment of obesity that comprises administering the patient a pharmaceutically active quantity of a composition in accordance with the invention.
Serum, administration vehicle of rCT-1). The results are expressed as mean±SE. n=5 animals per group. **p<0.01; ***p<0.001.
The authors of the present invention have observed that, surprisingly, CT-1 is capable of causing weight reduction in mice fed a normal diet as well as in mice fed a high-fat diet. Said effect depends, at least in part, on the anorexigenic effect of CT-1 (
Thus, in a first aspect, the invention is related to a compound that induces cardiotrophin 1 (CT-1) activity for the treatment of a metabolic disease. Additionally, the invention is related to the use of a compound that induces cardiotrophin-1 activity for the preparation of a drug for the treatment of a metabolic disease as well as with a method of treatment of a metabolic disease which comprises administration to a subject of a compound that induces CT-1 activity.
The term “compound that induces cardiotrophin-1 activity”, as used here, is understood as any compound administration of which causes an increase in cardiotrophin-1 activity (CT-1) irrespective of whether said increase is caused by an increase in the specific activity of the pre-existing CT-1 or by an increase in the synthesis of CT-1 or analogs thereof that substantially share the same function as cardiotrophin. Thus, in a preferred embodiment, the agent that induces CT-1 activity is CT-1 itself “CT-1” is understood as the protein defined by the sequence described in the UniProtKB database by access number CTF1_HUMAN or Q16619 in version 62 dated 16Dec. 2008, corresponding to isoform 1 of human cardiotrophin, or access number Q5U5Y7 in its version 1 dated 20 Jan. 2009, corresponding to isoform 2 of human cardiotrophin, as well as orthologues in other species, such as mouse (sequences defined in the UniProtKB database with access numbers NP—031821 or Q60753 in version 50 dated 16 Dec. 2008, and NP—942155 or P83714 in version 42 dated 16 Dec. 2008), rat (sequences defined in the UniProtKB database with access numbers NP—058825 or Q63086 in version 50 dated 04 Nov. 2008, and NP—001129272 or Q6R2R3 in version 30 dated 20 Jan. 2009) and chimpanzee (sequence defined in the UniProtKB database with access number NP—001009112 or Q6R2R2 in version 30 dated 04 Nov. 2008).
In another embodiment, the agent that induces CT-1 activity is a functionally equivalent variant of CT-1. The expression “functionally equivalent variant of CT-1”, as used here, is understood as any molecule which shares with CT-1 one or more of the functions described in the present invention associated to CT-1, both in vitro and in vivo and which has a minimum identity in the amino acid sequence. Thus, variants of CT-1 suitable for their use in the present invention are derived from the aforementioned sequences by insertion, substitution or deletion of one or more amino acids and include natural alleles, variants resulting from alternative processing and secreted and truncated forms which appear naturally. Preferably, the variants of CT-1 preferably show an identity of sequence with CT-1 of at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98% or at least 99%. The degree of identity is determined using methods very well known to those skilled in the art. The identity between two amino acid sequences is preferably determined using the BLASTP algorithm [BLASTManual, Altschul, S., et al., NCBI NLM NIH Bethesda, Md. 20894, Altschul, S., et al., J. Mol. Biol. 215: 403-410 (1990)] preferably using the default parameters. On the other hand, the variants of CT-1 envisaged show at least one of the functions of CT-1 such as, without limitation:
In another embodiment, the agent capable of inducing CT-1 activity is a polynucleotide that codes for CT-1 or a functionally equivalent variant thereof.
The term “polynucleotide”, as used in the present invention, relates to a polymeric form of nucleotides of any length and formed by ribonucleotides and/or deoxyribonucleotides. The term includes both single-chain and double-chain polynucleotides, as well as modified polynucleotides (methylated, protected and such like).
Polynucleotides suitable for use as agents capable of inducing CT-1 activity include, without limitation, the polynucleotides the sequences of which correspond to those described in the GenEMBL database with access numbers BC064416 in version 9 with date 15 Oct. 2008, corresponding to variant 1 of the transcript of human cardiotrophin, BC036787 in version 9 with date 12 Aug. 2009, corresponding to variant 1 of the transcript of human cardiotrophin, the sequence described in the GenEMBL database with access number D78591, in its version 4 of 12 Jan 2009, corresponding to the polynucleotide that codes for cardiotrophin 1 of Rattus norvegicus (rat), the sequence described in the GenEMBL database with access number AY518205, in its version 3 of 12 Jan. 2009, corresponding to the polynucleotide that codes for cardiotrophin 2 of Rattus norvegicus (rat), the sequence described in the GenEMBL database with access number U18366, in its version 4 of 12 Jan. 2009, corresponding to the polynucleotide that codes for cardiotrophin 1 of Mus musculus (mouse), the sequence described in the GenEMBL database with access number AB125661, in its version 2 of 12 Jan. 2009, corresponding to the polynucleotide that codes for cardiotrophin 2 of Mus musculus (mouse).
Alternatively, the agents capable of inducing CT-1 activity include functionally equivalent variants of the polynucleotides previously defined by means of their specific sequences. “Functionally equivalent polynucleotide” is understood, in the context of the present invention, as all those polynucleotides capable of coding for a polypeptide with CT-1 activity, as previously defined, and which result from the aforementioned polynucleotides by means of the insertion, deletion or substitution of one or several nucleotides with respect to the aforementioned sequences. Preferably, the variant polynucleotides of the present invention are polynucleotides the sequence of which allows them to hybridize in highly restrictive conditions with the aforementioned polynucleotides. Typical conditions of highly restrictive hybridization include incubation in 6×SSC (1×SSC: 0.15 M NaCl, 0.015 M sodium citrate) and 40% formamide at 42° C. for 141 hours, followed by one or several cycles of washing using 0.5×SSC, 0.1% SDS at 60° C. Alternatively, highly restrictive conditions include those which comprise hybridization at an approximate temperature of 50°-55° C. in 6×SSC and a washing final at a temperature of 68° C. in 1-3×SSC. The moderate restrictive conditions comprise hybridization at a temperature of approximately 50° C. until 65° C. in 0.2 or 0.3 M NaCl, followed by washing at approximately 50° C. until 55° C. in 0.2×SSC, 0.1% SDS (sodium dodecyl sulfate).
Preferably, when the agent capable of inducing CT-1 activity is a polynucleotide, this is operationally associated to a regulatory region of the expression. The regulatory sequences used in the present invention can be nuclear promoter sequences or, alternatively, enhancer sequences and/or other regulatory sequences that increase the expression of the heterologous nucleic acid sequence. The promoter can be constitutive or inducible. If one wants a constant expression of the heterologous nucleic acid sequence, then a constitutive promoter is used. Examples of well-known constitutive promoters include the cytomegalovirus (CMV) immediate-early promoter, Rous sarcoma virus promoter and such like. Many other examples of constitutive promoters are well known in the state of the art and can be used in the practice of the invention. If the controlled expression of the heterologous nucleic acid sequence is desired, then an inducible promoter should be used. In a non-induced state, the inducible promoter is “silent”. “Silent” means that in the absence of an inducer little or no expression of the heterologous nucleic acid sequence is detected; in the presence of an inducer, however, the expression occurs of the heterologous nucleic acid sequence. Frequently, it is possible to control the expression level by varying the inducer concentration. Controlling the expression, for example varying the concentration of the inducer so that an inducible promoter is more strongly or more weakly stimulated, it is possible to affect the concentration of the transcript product of the heterologous nucleic acid sequence. In the case that the heterologous nucleic acid sequence codes for a gene, it is possible to control the quantity of synthesized protein. In this way, it is possible to vary the concentration of the therapeutic product. Examples of well-known inducible promoters are: an estrogen or androgen promoter, a metallothionein promoter, or a promoter that responds to ecdysone. Many other examples are well known in the state of the art and can be used in the practice of the invention. In addition to the constitutive and inducible promoters (which usually function in a great variety of cells or tissues), specific tissue promoters can be used to achieve expression of the heterologous sequence of specific nucleic acid in cells or tissues. Well-known examples of specific tissue promoters include different specific muscle promoters including: skeletal α-actin promoter, cardiac actin promoter, skeletal troponin C promoter, cardiac troponin C promoter and of slow contraction, and the creatine kinase promoter/enhancer. There are specific muscle promoters which are well known in the state of the art and which can be used in the practice of the invention (for a review of specific muscle promoters, see Miller et al., (1993) Bioessays 15: 191-196).
In another embodiment, the agent capable of inducing CT-1 activity is a vector that comprises a polynucleotide as previously defined, i.e. that codes for CT-1 or a functionally equivalent variant thereof. Suitable vectors for the insertion of said polynucleotides are vectors derived from expression vectors in prokaryotes such as pUC18, pUC19, pBluescript and their derivatives, mp18, mp19, pBR322, pMB9, Co1E1, pCR1 , RP4, phages and “shuttle” vectors such as pSA3 and pAT28, yeast expression vectors such as vectors of the 2 micron plasmid type, integration plasmids, YEP vectors, centromeric plasmids and such like, expression vectors in insect cells such as the vectors of the pAC series and of the pVL series, expression vectors in plants such as vectors of the pIBI, pEarleyGate, pAVA, pCAMBIA, pGSA, pGWB, pMDC, pMY, pORE series and such like and expression vectors in eukaryote cells either based on viral vectors (adenovirus, virus associated to adenovirus as well as retrovirus and, in particular, lentivirus) as well as non-viral vectors such as pSilencer 4.1-CMV (Ambion), pcDNA3, pcDNA3.1/hyg pHCMV/Zeo, pCR3.1, pEF1/His, pIND/GS, pRc/HCMV2, pSV40/Zeo2, pTRACER-HCMV, pUB6/V5-His, pVAX1, pZeoSV2, pCI, pSVL and pKSV-10, pBPV-1, pML2d and pTDT1.
In another embodiment, the agent capable of causing an increase in CT-1 activity is a cell capable of secreting cardiotrophin-1 or a functionally equivalent variant thereof into the medium. Suitable cells for the expression of cardiotrophin-1 or of the functionally equivalent variant thereof include, without limitation, cardiomyocytes, adipocytes, endothelial cells, epithelial cells, lymphocytes (B and T cells), mastocytes, eosinophils, cells of the vascular intima, primary culture of cells isolated from different organs, preferably from cells isolated from islets of Langerhans, hepatocytes, leukocytes, including mononuclear, mesenchymal, umbilical cord or adult leukocytes (from the skin, lungs, kidney and liver), osteoclasts, chondrocytes and other connective tissue cells. Established cell lines such as Jurkat t cells, NIH-3T3, CHO, Cos, VERO, BHK, HeLa, COS, MDCK, 293, 3T3 cells, C2C12 myoblasts and W138 cells are also suitable.
Those skilled in the art will appreciate that cells capable of secreting cardiotrophin-1 or a functionally equivalent variant thereof into the medium can be found forming microparticles or microcapsules so that the cells have a greater useful life before being used in patients. Suitable materials for forming the microparticles that are an object of the invention include any biocompatible polymeric material that allows the continuous secretion of therapeutic products, acting as cell support. Thus, said biocompatible polymeric material can be, for example, thermoplastic polymers or hydrogel polymers. Thermoplastic polymers include acrylic acid, acrylamide, 2-aminoethyl methacrylate, poly(tetrafluoroethylene-cohexafluoropropylene), methacrylic-(7-cumaroxy) ethyl ester acid, N-isopropyl acrylamide, polyacrylic acid, polyacrylamide, polyamidoamine, poly(amino)-p-xylylene, poly(chloroethyl vinyl ether), polycaprolactone, poly(caprolactone-co-trimethylene carbonate), poly(carbonate urea) urethane, poly(carbonate) urethane, polyethylene, polyethylene copolymer and acrylamide, polyethylene glycol, polyethylene glycol methacrylate, poly(ethylene terephthalate), poly(4-hydroxybutyl acrylate), poly(hydroxyethyl methacrylate), poly(N-2-hydroxypropyl methacrylate), poly(lactic acid-glycolic acid), poly(L lactic acid), poly(gamma-methyl, L-glutamate), poly(methylmethacrylate), poly(propylene fumarate), poly(propylene oxide), polypyrrole, polystyrene, poly(tetrafluoroethylene), polyurethane, polyvinyl alcohol, ultra-high molecular weight polyethylene, 6-(p-vinybenzamide)-hexanoic acid and N-p-vinylbenzyl-D-maltonamide and copolymers which contain more than one of said polymers. The polymers of hydrogel type include natural materials of alginate, agarose, collagen, starch, hyaluronic acid, bovine serum albumin, cellulose and its derivatives, pectin, chondroitin sulfate, fibrin and fibroin type as well as synthetic hydrogels such as sefarose and sefadex.
It is known in the state of the art that some of said polymers are unstable and tend to lose their gel nature, in addition to being relatively porous, which means that antibodies may access their interior and damage the cells. For this reason, optionally, the microparticle of the invention can be surrounded by a semi-permeable membrane which gives stability to the particles, forming a barrier impermeable to antibodies. Semipermeable membrane means a membrane that allows the entry of all those solutes necessary for cell viability and allows the exit of therapeutic proteins produced by the cells contained in the microparticle, but which is substantially impermeable to antibodies, so that the cells are protected from the immune response produced by the organism housing the microparticle. Suitable materials for forming the semipermeable membrane are materials insoluble in biological fluids, preferably polyamino acids, such as, for example poly-L-lysine, poly-L-ornithine, poly-L-arginine, poly-L-asparagine, poly-L-aspartic, poly benzyl-L-aspartate, poly-S-benzyl-L-cysteine, poly-gamma-benzyl-L-glutamate, poly-S-CBZ-L-cysteine, poly-ε-CBZ-D-lysine, poly-δ-CBZ-DL-ornithine, poly-O-CBZ-L-serine, poly-O-CBZ-D-thyrosine, poly(γ-ethyl-L-glutamate), poly-D-glutamic, polyglycine, poly-γ-N-hexyl L-glutamate, poly-L-histidine, poly(α,β-[N-(2-hydroxyethyl)-DL-aspartamide]), poly-L-hydroxyproline, poly (α,β-[N-(3-hydroxypropyl)-DL-aspartamide]), poly-L-isoleucine, poly-L-leucine, poly-D-lysine, poly-L-phenylalanine, poly-L-proline, poly-L-serine, poly-L-threonine, poly-DL-tryptophan, poly-D-thyrosine or a combination thereof.
The term “metabolic disease”, as used here, is understood as all types of disorders that lead to errors and imbalances in the metabolism as well as to metabolic processes taking place in a sub-optimal form. The expression also relates to disorders that can be treated through metabolism modulation, although the disease in itself may not have been caused by a metabolic disorder. In a preferred embodiment, the metabolic disease is selected from the set of obesity, hyperglycaemias, insulin resistance, type 2 diabetes, and dyslipemias.
The term “obesity”, as used in the present invention, relates to the definition of obesity provided by the WHO based on the body mass index (BMI), which consists of the ratio between the weight of a person (in kg) and the square of their height in metres. According to this criteria, a BMI lower than 18.5 kg/m2 is considered as insufficient weight or thinness, a BMI of 18.5-24.9 kg/m2 is considered a normal weight, a BMI of 25.0-29.9 kg/m2 is considered grade 1 of overweight, a BMI of 30.0-39.0 kg/m2 is considered a grade 2 of overweight and a BMI greater than or equal to 40.0 kg/m2 is considered morbid obesity. Alternatively, there are alternative methods for defining the an individual's degree of obesity, such as the diameter of the waist measured at the midpoint between the lower limit of the ribs and the upper limit of the pelvis (in cm), the thickness of skin folds, and bioimpedance, based on the principle that a lean mass transmits electricity better than a fatty mass.
The term “hyperglycaemia”, as used in the present invention, relates to a state where abnormally high blood glucose levels appear in relation to the fasting baseline levels. In particular, hyperglycaemia is understood to take place when fasting blood glucose levels are consistently higher than 126 mg/dL, the postprandial glucose levels are higher than 140 mg/dL, and/or the glucose levels in venous plasma 2 hours after administration of a dose of glucose of 1.75 grams for each kilogram of body weight is over 200 mg/dL.
The term “insulin resistance”, as used in the present invention, relates to a disorder wherein the cells do not respond correctly to insulin. As a result, the body produces more insulin in response to high blood glucose levels. Patients with insulin resistance frequently display high glucose levels and high circulating insulin levels. Insulin resistance is frequently linked to obesity, hypertension, and hyperlipidemia. Additionally, insulin resistance frequently appears in patients with type 2 diabetes.
The term “type 2 diabetes”, as used in the present invention, relates to a disease characterized by an inappropriate increase in blood glucose levels, which generates chronic complications as it affects large and small vessels and nerves. The underlying disorder in this disease is the difficulty for insulin action (in the form of a loss of tissue sensitivity to this hormone), which is called insulin resistance, and an inadequate secretion of insulin by the cells responsible for their production in the pancreas. In addition to increasing glucose concentration, faulty insulin action frequently translates into an increase in cholesterol and/or triglyceride levels.
The term “dyslipemia”, as used in the present invention, relates to any pathological condition characterized by a disorder in the lipid metabolism, with a consequent disorder in lipid concentration (cholesterol, triglycerides and such like) and lipoproteins (high density lipoproteins) in the blood. Dyslipemias that can be treated with the methods of the present invention include, without limitation, hypercholesterolemia, hypertriglyceridemia, hyperlipoproteinemia of type I, IIa, IIb, III, IV, V, hyperchylomicronemia, combined hyperlipidemia, etc.
The compositions of the invention are useful both for the treatment of morbid obesity and for the treatment of grade 1 or grade 2 of overweight, in which case the methods of the invention have a cosmetic purpose. Therefore, in another aspect, the invention is related to a cosmetic method for the treatment of obesity which comprises administering to a patient a compound that induces cardiotrophin 1 activity. In this embodiment, the patients with excess weight in the form of fat and who can be treated by the cosmetic method of the present invention are identified visually or by having a BMI higher than or equal to 25 kg/m2, preferably between 25 and 30. These individuals are considered obese, and needing weight control for cosmetic reasons.
The different embodiments of the cosmetic method in accordance with the invention as regards agents capable of inducing cardiotrophin-1 activity have been described previously in the context of the methods of treatment of obesity and other metabolic diseases.
The compounds of the invention can be administered both for acute and for chronic treatment. The expression “chronic administration”, as used in the present invention, relates to a method of administration wherein the compound is administered to the patient continuously for extended periods of time in order to maintain the therapeutic form during said period. Forms of chronic administration include the administration of multiple doses of the compound daily, twice daily, thrice daily or with more or less frequency. Chronic administration can be carried out by means of different intravenous injections administered periodically throughout a single day. Alternatively, chronic administration involves the administration in the form of bolus or by continuous transfusion which can be carried out daily, every two days, every 3 to 15 days, every 10 days or more. Typically, chronic administration is maintained for at least 72 hours, at least 96 hours, at least 120 hours, at least 144 hours, at least 1 week, at least 2 weeks, at least 3 weeks, at least 4 weeks, at least 5 weeks, at least 6 weeks, at least 7 weeks, at least 8 weeks, at least 9 weeks, at least 10 weeks, at least 11 weeks, at least 12 weeks, at least 4 months, at least 5 months, at least 6 months, at least 9 months, at least one year, at least 2 years or more.
The expression “acute administration”, as used in the present invention, relates to a method of administration wherein the patient is exposed to a single dose of the compound or several doses but over a reduced time period, such as, for example, 1, 2, 4, 6, 8, 12 or 24 hours or 2, 3, or 4 days.
Those skilled in the art will appreciate that the effective therapeutic quantity and/or formulation of the active compound shall be carried out depending on the type of administration. “Therapeutically effective quantity”, as used here, is understood as the quantity of compound that makes it possible to totally or partially alleviate the symptoms associated with a metabolic disease or which prevents the progression or worsening the symptoms or which prevents the appearance of the disease in a subject at risk from suffering the disease.
If chronic administration of the compound of the invention is desired, it can be administered in a sustained release composition such as that disclosed in documents U.S. Pat. No. 5,672,659, U.S. Pat. No. 5,595,760, U.S. Pat. No. 5,821,221, U.S. Pat. No. 5,916,883 and WO9938536. Otherwise, if acute administration is desired, a treatment with immediate release will be preferred. Irrespective of the type of administration, the quantity of the dose and the interval can be individually adjusted to provide plasma levels of the compounds sufficient for maintaining the therapeutic effect. Someone with normal experience in the state of the art will be capable of optimizing the therapeutically effective local doses without too much experimentation.
Administration of the compounds of the invention requires their formulation in pharmaceutical compositions, which constitute another aspect of the invention. Useful pharmaceutical compositions in the practice of the method of the invention include a therapeutically effective quantity of an active agent, and pharmaceutically acceptable carrier. The term “pharmaceutically acceptable” means approved by a regulatory agency of the Federal government or of a state or included in the USA Pharmacopoeia or another generally recognized pharmacopoeia, for use in animals, and more particularly in humans. The term “carrier” relates to a diluent, coadjuvent, excipient, or vehicle whereby the therapeutic compound is administered. Said pharmaceutical carriers can be sterile liquids, such as water and oils, including petroleum, animal or plant origin or synthetic oils, such a peanut oil, soy oil, mineral oil, sesame oil and such like. Suitable pharmaceutical excipients include starch, glucose, lactose, sucrose, gelatine, malt, rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate, talc, sodium chloride, powdered skimmed milk, glycerol, propylene glycol, water, ethanol and such like. The composition, if desired, can also contain smaller quantities of wetting or emulsifying agents, or pH buffering agents. These compositions may take the form of solutions, suspensions, tablets, pills, capsules, powder, prolonged release formulations and such like. The composition may be formulated as a suppository, with binders and traditional carriers such as triglycerides. The oral formulation can include standard carriers such as pharmaceutical types of mannitol, lactose, starch, magnesium stearate, sodium saccharin, cellulose, magnesium carbonate, etc. Examples of suitable pharmaceutical carriers are described in “Remington's Pharmaceutical Sciences” by E. W. Martin.
The composition can be formulated in accordance with routine procedures as a pharmaceutical composition adapted for intravenous, subcutaneous, or intramuscular administration to human beings. When necessary, the composition may also include a solubilising agent and a local anaesthetic such as lidocaine to relieve pain at the injection site. When the composition is going to be administered by infiltration, it can be dispensed with an infiltration bottle which contains water or saline solution of pharmaceutical quality. When the composition is administered by injection, a water vial can be provided for injection or sterile saline solution, so that the ingredients can be mixed before administration.
The quantity of CT-1 activity inducing compound that will be effective in the treatment of metabolic disease can be determined by standard clinical techniques based on the present description. Furthermore, in vitro tests can also be optionally used to help identify optimum dosage ranges. The precise dose to use in the formulation will depend on the administration route, and the severity of the condition, and it should be decided at the doctor's judgement and depending on each patient's circumstances. However, the dosage ranges suitable for intravenous administration are generally 50-5000 micrograms of active compound per kilogram of body weight. The dosage ranges suitable for intranasal administration are generally approximately of 0.01 pg/kg of body weight to 1 mg/kg of body weight. The effective doses can be extrapolated from a pair of response curves to doses derived from model in vitro assay systems or in animals.
For systemic administration, a therapeutically effective dose can be initially estimated from in vitro assays. For example, a dose can be formulated in animal models to achieve a circulating concentration range which includes the IC50 which has been determined in cell culture. Said information can be used to precisely determine useful doses in humans. The initial doses can also be estimated from in vivo data, e.g. animal models, using techniques well known in the state of the art. Someone with normal experience in the state of the art can easily optimize administration to humans based on the data in animals.
Likewise, the invention envisages the combined use of the agent capable of inducing CT-1 activity with one or several compounds capable of reducing the availability of nutrients in the organism, which have an anorexigenic effect or which have an anti-obesity effect. Thus, the metabolic disease treatment methods in accordance with the invention envisage the joint, sequential or separate administration of the compounds with capacity for inducing CT-1 activity with one or several compounds selected from the group of amylin, amylin agonists, calcitonin salmon, cholecystokinin or an agonist thereof, leptin (OB protein), exendin or an exendin analog, GLP1 or an agonist thereof, polypeptides (PYY) or agonists thereof, agents that affect neurotransmitters or neuronal ion channels such as anti-depressants, noradrenaline capture inhibitors, serotinin 2c receptor agonists, some dopaminergic antagonists, cannabinoid 1 receptor agonists, agents which modulate the route of leptin/insulin in the CNS including leptin analogs, promoters of leptin transport or promoters of the leptin receptor, CNTF, neuropeptide Y, antagonists of the peptide related to agouti, proopiomelanocortin, cocaine, amphetamine, alpha-melanocyte stimulating hormone, melanocortin-4 receptor agonists, agents which affect insulin activity/metabolism as protein tyrosine phosphate 1 beta inhibitors, antagonists of the receptor activated by the peroxisome 7 proliferator, bromocriptine, somatostatin agonists, agents that increase the metabolic rate at rest (agonists of the uncoupling protein, agonists of the thyroid hormone receptor) as well as other agents of different type such as melanin, analogs of phytostanol, functional oils, fatty acid synthesis inhibitors, carboxypeptidase inhibitors, intestinal lipase inhibitors and such like.
The authors of the present invention have observed that, surprisingly, the joint administration of CT-1 and insulin has hypoglycaemic effects on models of type 1 diabetes and on glucose capture by muscles which are higher than those observed by the administration of each component separately. Thus,
Therefore, in another aspect, the invention is related to a composition (hereinafter, composition of the invention) which comprises, together or separately, a compound that induces cardiotrophin activity and an anti-diabetic compound.
The expression “compound that induces cardiotrophin activity” has been described previously in the context of the methods of treatment of metabolic diseases and comprises, as in the first method of the invention, a compound selected from the group of
The expression “anti-diabetic compound”, as used in the present invention, is understood as an agent which, irrespective of its action mechanism, is capable of at least partially compensating for the symptoms of diabetes, including hyperglycaemia. In a preferred embodiment, the anti-diabetic compound is a compound that induces insulin activity or a compound that induces hypoglycaemic activity of insulin or sensitizing agent to insulin activity.
The anti-diabetic compounds capable of inducing insulin activity include, without limitation,
The term “insulin”, as used in the present invention, relates to insulin of any species (primate, rodent or rabbit), but preferably of human origin and more preferably insulin of native sequence, which comprises a polypeptide which has the same sequence of amino acids as the insulin derived from nature. Said insulin polypeptides of native sequence can be isolated from nature or can be produced by recombinant and/or synthetic medium. The term “native sequence insulin” specifically covers the truncated or secreted forms and allelic variants that occur naturally. In an embodiment of the invention, the native sequence human insulin is a mature native sequence insulin or of a complete length which comprises an alpha or A chain, corresponding to amino acids 90 to 110 of the sequence of human preproinsulin (access number P01308 in the UniProtKB database in version 126 with date 20 Jan. 2009) and a beta or B chain, corresponding to amino acids 25 to 54 (access number P01308 in the NCBI database in version 126 with date 20 Jan. 2009).
“Functionally equivalent variant of insulin”, as used in the present invention, is understood as all those polypeptides resulting from the elimination, insertion or modification of at least one amino acid with respect to the insulin sequence and which substantially maintains the same properties as the insulin it comes from. Insulin activity can be determined by methods widely known by those skilled in the art such as normoglycaemic clamping or the measurement of glycosylated proteins in serum (Bunn et al., Diabetes, 1981, 30:613-617).
Functionally equivalent variants of insulin include, without limitation, the des-pentapeptide (B26-B30)-PheB25-α-carboxamide]insulin, AspB10 insulin (disclosed in U.S. Pat. No. 4,992,417), LysB28-ProB29 insulin LysB28-ProB29 and the hexameric variant thereof (disclosed in U.S. Pat. No. 5,474,978 and U.S. Pat. No. 5,514,646), formulations of insulin and protamine (U.S. Pat. No. 5,650,486), acylated LysB28-ProB29 insulin (U.S. Pat. No. 5,922,675), and compositions of stabilized insulin such as those disclosed in U.S. Pat. No. 5,952,297, U.S. Pat. No. 6,034,054 and U.S. Pat. No. 6,211,144, superactive analogs of insulin, monomeric insulins, hepatospecific insulins, insulin lispro (Humalog®), insulin lispro formulated with insulin lispro protamine (marketed as Humalog® 50/50™, Humalog® 75/25™), NPH insulin or insulin isophane human (marketed as Humulin®), regular insulin, NPH insulin combined with regular insulin (U.S. Pat. No. 5,547,929), insulin zinc, insulin glargine, glulisine (APidra), insulin Aspart (Novomix), insulin detemir (levemir), biota, LP-100, novarapid, insulin zinc suspension (slow and ultraslow), GLP-I (1-36) amide, GLP-I (73-7) (insulinotropin disclosed in U.S. Pat. No. 5,614,492), LY-315902 (Lilly), GLP-I (7-36)-NH2), AL-401 (Autoimmune), compositions such as those disclosed in U.S. Pat. No. 4,579,730, U.S. Pat. No. 4,849,405, U.S. Pat. No. 4,963,526, U.S. Pat. No. 5,642,868, U.S. Pat. No. 5,763,396, U.S. Pat. No. 5,824,638, U.S. Pat. No. 5843866, U.S. Pat. No. 6,153,632, U.S. Pat. No. 6,191,105, and WO 85/05029.
Additionally, functionally equivalent variants of insulin include polypeptides that show at least approximately 80% of identity of amino acid sequence with the sequence of amino acids of: (a) residues 1 to 21 of the high-fat diet A chain in combination with residues 1 to 30 of the high-fat diet B chain, or (b) another fragment specifically derived from said sequences. Furthermore, the secondary structure of the insulin maintained by disulfide bonds between cysteine residues A6-A11, A7-B7 and A20-B19 seems necessary for the activity, for which reason the functionally equivalent variants preferably preserve said secondary structure as much as possible.
Functionally equivalent variants of insulin include, for example, the polypeptides wherein one or more amino acid residues are added, or deleted, at the N- and/or C-terminal ends, as well as within one or more of the internal domains, of the A and B chains of insulin. Normally, a polypeptide variant of insulin will have at least approximately an identity of amino acids sequence with the sequence formed by residues 1 to 21 of the A chain of the high-fat diet in combination with residues 1 to 30 of the B chain of the high-fat diet or with another fragment specifically derived from said sequences of amino acids of at least 80%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% of identity of amino acids sequence. The polypeptide variants will have a sequence length of at least 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34 or 35 of the A chain and at least 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 27, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49 or 50 residues of the B chain.
Polynucleotides which code for insulin include both the polynucleotide that codes for human insulin as well as the precursors thereof (preproinsulin and proinsulin), as well as the orthologs of other species.
“Polynucleotide that codes for a functionally equivalent variant of insulin” indicates (a) a nucleic acid that codes for a polypeptide of active insulin as defined above, and which has at least approximately 80% identity of nucleic acid sequence with a nucleic acid sequence that codes for: (a) residues 1 to 21 of the A chain of the high-fat diet defined above in combination with residues 1 to 30 of the B chain of the human insulin polypeptide defined above, or (b) one of nucleic acid that codes for another fragment specifically derived from the aforementioned sequences of amino acids which shows at least 80%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% of identity of amino acid sequence with said sequences. The polynucleotides which code for a variant of insulin contain a nucleic acid that codes for an A chain of insulin of at least approximately 45, 48, 51, 54, 57, 60, 63, 66, 69, 72, 75, 81, 87, 105 nucleotides and/or a nucleic acid that codes for a B chain of insulin of at least approximately 75, 78, 81, 84, 87, 90, 93, 96, 99, 102, 105, 108, 111, 114, 117, 120, 123, 126, 129, 132, 135 or 150 nucleotides.
Said polynucleotides may appear isolated or be found as part of a vector. Suitable vectors for the expression of the polynucleotides that code for insulin or the functionally equivalent variant thereof are essentially the same as those previously described in relation to the composition comprised by CT-1.
Alternatively, the anti-diabetic compounds that can be used in the context of the present invention include compounds which that antiglycaemic activity of the insulin or sensitizing agents of insulin activity and include, without limitation, secretagogues of insulin such as the sulfonylureas (tolbutamide, chlorpropamide, glipicide, glibenclamide, glicazide, glipentide, glimepiride, glibenclamide, glipizide, gliquidone, glisentide, glimepride and such like) and metiglinides (repaglinide, nateglinide, mitiglinide and such like), reducing agents of liver glucose production (biguanides and, in particular, metformin and buformin), agents which cause carbohydrate decrease such as α-glucosidase inhibitors (acarbose, miglitol or voglibose), agents that increase peripheral use of glucose such as thiazolidinediones (rosiglitazone, pioglitazone and such like), GLP- or a GLP-1 mimetic (Byetta-Exanatide, Liraglutinide, CJC-1131 (ConjuChem, Exanatide-LAR (Amylin), BIM-51077, ZP-10, the compounds described in WO 00/07617 and such like), exendin, secretin, DPP-IV inhibitors (sitagliptin, saxagliptin, denagliptin, vildagliptin, ALS-2-0426, ARI- 2243, BI-A, BI-B, SYR-322, MP-513, DP-893, RO-0730699 and such like), SGLT-2 inhibitors (dapagliflozin, and sergliflozin, AVE2268, T- 1095 and such like) and peptides that cause an increase in glucose production (amlintide, pramlintide, exendin), compounds with GLP-1 activity (glucagon-like peptide 1), inhibitors of the protein tyrosine phosphatase 1B, dipeptidyl peptidase inhibitors, secretagogues of insulin; fatty acid oxidation inhibitors, A2 antagonists, c-jun terminal kinase inhibitors, insulin; insulin mimetics, glycogen phsophorylase inhibitors, VPAC2 receptor agonists, glucokinase inhibitors, etc.).
The compositions of the invention can be used for the treatment of metabolic disease given their hypoglycaemic effects and their capacity to increase glucose capture by muscles (see example 2). Said compositions can be used as preparations of the different compounds for their administration simultaneously, separately or sequentially. Thus, in another aspect, the invention is related to a composition of the invention for the treatment of a metabolic disease wherein the composition is administered simultaneously, separately or sequentially. In another aspect, the invention is related to the use of a composition of the invention for the preparation of a drug for the treatment of a metabolic disease wherein the composition is administered simultaneously, separately or sequentially. In another aspect, the invention is related to a method for the treatment of a metabolic disease which comprises the simultaneous, separate or sequential administration of a composition of the invention.
The therapeutic agents of the compositions of the invention, in particular, the CT-1 activity inducer agent and the anti-diabetic agent, can be presented as a single formulation (for example, as a tablet or a capsule comprising a fixed quantity of each one of the components) or can, on the other hand, be presented as separate formulations to be later combined for joint, sequential, or separate administration. The compositions of the invention also include the formulation as a kit-of-parts wherein the components are formulated separately but are packaged in the same container. Those skilled in the art will appreciate that the formulation of the first and second components of the compositions of the invention may be similar, in other words, similarly formulated (in tablets or pills), which allows their administration by the same route. In the case where the different components of the invention are formulated separately, the two components can be presented in a blister. Each blister contains the drugs that must be consumed during the day. If the drugs must be administered several times a day, the drugs corresponding to each administration can be placed in different sections of the blister, preferably recording in each section of the blister the time of day when they should be administered. Alternatively, the components of the composition of the invention can be formulated differently so that the different components are differently administered. Thus, it is possible that the first component is formulated as a tablet or capsule for its oral administration and the second component is formulated for its intravenous administration.
The compositions of the invention are administered by the methods known to those skilled in the art, including, but without limitation, intravenous, oral, nasal, parenteral, topical, transdermal, rectal, and such like.
The ratio between the components that are part of the compositions of the invention shall depend on the CT-1 activity inducer agent and the anti-diabetic agent used in each particular case, as well as of the desired indication. Thus, the invention envisages compositions wherein the ratio between the quantities of the two components can range from 50:1 to 1:50, in particular from 20:1 to 1:20, from 1:10 to 10:1, or from 5:1 to 1:5.
The metabolic diseases that can be treated with the compositions of the invention include, without limitation, obesity, insulin resistance, hyperglycaemia, dyslipemia, and type 2 diabetes, as has been previously described in relation to the first aspect of the invention (therapeutic and cosmetic uses of CT-1). In another embodiment, the invention is related to a cosmetic method for the treatment of obesity which comprises administering a patient a composition in accordance with the invention, wherein those patients candidate to an anti-obesity treatment for purely cosmetic reasons are identified as has been described in the first aspect of the invention (therapeutic and cosmetic uses of CT-1).
The invention is described below by the following examples that should be considered merely illustrative and in no case limitative of the scope of the present invention.
Obese mice were obtained by the intake of a high-fat diet (HFD, 60% fat) during 3 months. The intravenous administration for 6 consecutive days of rCT-1 (0.2 mg/kg/day) caused a reduction in the body weight of C57BL/6 mice (5 months of age) with high-fat diet (HFD) (
The decrease in body weight observed in the obese mice, (fed HFD as described in
Likewise, the intravenous administration of rCT-1 (0.2 mg/kg/day) for 6 consecutive days reduced body weight in non-obese C57BL/6 mice (5 months of age) fed a normal diet (NCD) (
With the purpose of determining whether the reduction in body weight observed during treatment with rCT-1 with the dose and in the previously commented form was due to an anorexigenic effect or involved other effects, a study was performed using 3 groups of C57BL/6 mice of 4 months of age. The first group (Saline group) received a physiological serum intravenously (the same volume as that used for the administration of rCT-1); the second group (rCT-1 group) received rCT-1 intravenously at the aforementioned dose (0.2 mg/kg/day) and the third group (Pair-Fed group) received the same quantity of food daily as that ingested by the mice treated with rCT-1 and which were injected with serum during the same experimental period. As observed in
With the purpose of determining whether the acute intravenous administration of a single dose of rCT-1 (10 μg) to C57BL/6 mice (3 months of age) reduced the baseline blood sugar levels, the blood glucose levels were measured 1 hour after treatment with rCT-1 and saline serum. As observed in
The acute administration of a single dose of rCT-1 (10 μg) prevents the increase of blood glucose after a high sugar diet. This experiment to study the effects of rCT-1 on the post-pandrial blood sugar was performed on mice (C57BL/6, 3 months of age) administered a high sugar diet by gastric gavage (in a volume 1% body weight) in accordance with that published by Fruebis et al. (Fruebis et al., 2001, Proc. Natl. Acad. Sci. USA., 98:2005-2010). After performing the gavage, the intravenous administration of the same volume of saline serum was given (Saline) or rCT-1 (10 μg). Blood was taken at the hours indicated in the graphic and blood sugar was measured observing that no increase in blood sugar occurred in the animals treated with rCT-1 (
Next, it was determined whether acute administration of a single rCT-1 dose decreases blood sugar levels in mice (C57BL/6, 3 months of age) was capable of decreasing hyperglycaemia secondary to the destruction of beta-pancreatic cells performed with treatment with streptozotocin. Therefore, 64 hours after administration of a single dose of streptozotocin (200 mg/kg), the baseline blood sugar was measured and the different treatments were performed on 3 groups of mice. The first group (saline group) was treated with treated with saline serum; the second group (Insulin group) was treated with 0.75 U/kg insulin, the third group (rCT-1 group) was treated with 10 μg of rCT-1 and the fourth group (Insulin group+rCT-1) was treated with 0.75 U/kg of insulin and 10 μg of rCT-1. Once the different treatments have been administered, blood sugar was measured after 15, 30, 60 and 120 min. As observed in
In order to determine if the hypoglycaemic effect resulting from acute treatment with rCT-1 is due to an increase in glucose capture by muscles, muscular capture of 18FDG (18 FluoroDeoxyGlucose) was determined by gamma counter in different groups of mice. To perform this experiment, the mice (C57BL/6, 3 months of age) were divided into 4 groups as follows: Saline group (treated with saline serum); Insulin group (treated with 0.75 U/kg insulin), rCT-1 group (treated with 10 μg of rCT-1) and Insulin group+rCT-1 (treated with 0.75 U/kg of insulin+10 μg of rCT-1. 15 minutes after the administration of the different treatments 18FDG was administered and 10 minutes after the injection the gastrocnemius muscles were extracted, and the radioactivity emitted was quantified by gamma counter. The results (
Next, the hypoglycaemic and hypoinsulinemic effects of chronic treatment with rCT-1 were determined in C57BL/6 mice (5 months of age) with obesity induced by the intake of a high-fat diet (HFD, 60% fat) for 3 months. At the end of the dietary treatment, the mice were treated for 6 consecutive days (chronic treatment) with rCT-1 (0.2 mg/kg/day) administered endovenously. As shown in
Next, the hypoglycaemic and hypoinsulinemic effects of chronic treatment with rCT-1 were compared with their corresponding pair-fed (PF) group. The rCT-1 group received rCT-1 by intravenous route at the aforementioned dose (0.2 mg/kg/day) for 6 days; the Pair-Fed group received the same quantity of daily food as that ingested by the mice treated with rCT-1 and serum was injected into them for the same experimental period. As shown in
Then, it was determined whether the in vitro treatment with rCT-1 (0-100 ng/ml) is capable of inhibiting the transport of sugar in intestinal rings. Therefore, the intestinal transport of glucose was determined by measuring the capture of α-methylglucoside (1 mM) by everted jejunum rings for 15 minutes of incubation in the absence or presence of r-CT-1 at 37° C. The α-methylglucoside is an analog of the glucose which only crosses the apical membrane of the enterocyte by the SGLT1 sodium-sugar co-transcarrier, which means that the changes in their transport should be attributed to changes in the activity of said transcarrier.
Next, the actions of CT-1 and CNTF on the capture of α-methylglucoside (1 mM) in intestinal rings was determined. Following the experimental method described in
Next, it was determined whether the in vitro effects of CT-1 on the intestinal capture of glucose could be reproduced in vivo. To do this, rCT-1 (10 μg) was administered intravenously and acutely to C57BL/6 mice (2 months of age). It was observed that the administration of CT-1 caused an inhibition in the intestinal transport of α-methylglucoside (1 mM) (
It was later determined whether the intravenous administration of rCT-1 (0.2 mg/kg/day) for 6 consecutive days (chronic treatment) to C57BL/6 mice (5 months of age) was capable of inhibiting the intestinal capture of α-methylglucoside (1 mM) in intestinal rings in comparison with those from mice treated with saline serum. The results are shown in
Next, the effect of rCT-1 was determined on the capture of α-methylglucoside (0.1 mM) by cells of the CACO-2 human cell line. The results (
Aditionally and importantly, CT-1 is able to induce typical genes of brown adipose tissue in adipocytes (deiodinase iodothyronine type II, Dio-2 and uncoupling protein-1, UCP-1) while CNTF is not able (
Chronic administration of CT-1 does not result in inflammation In order to determine the capacity of CT-1 of producing inflammation after its chronic administration, serum levels of IL-6 in C57BL/6 mice were determined (5 months of age) with obesity induced by the intake of a high-fat diet (HFD, 60% fat) for 3 months. At the end of the dietetic treatment, the mice were treated for 6 consecutive days (chronic treatment) with rCT-1 (0.2 mg/kg/day) administered endovenously. The results (
Additionally, histological cuts of liver were performed in order to detect by microscopy the appearance of symptoms of inflammation. The results (
which received rCT-1 by intravenous route at the aforementioned dose (0.2 mg/kg/day) for 6 consecutive days; Pair-Fed group: which received the same quantity of daily food as that the mice treated with rCT-1 would ingest and into which serum was injected during the same experimental period. As observed in the figure, in none of the three groups do we observe the presence of inflammatory infiltrate, nor any other significant morphological alteration.
With the purpose of determining the possible role of CT-1 on the lipid metabolism, the levels of different serum lipids were determined in mice with high-fat diet-induced obesity for 3 months after chronic administration with rCT-1 for 6 days. The results are shown in Table 1
Additionally, the serum levels of fatty acids and triglycerides were determined in wild mice after a high-fat diet. To do this, two groups of animals were used (n=5) which remained fasting for 3 hours before the experiment. Next, both groups of animals were administered high fat food by gavage (1% of body weight) and a blood sample was obtained to determine the baseline levels Immediately after the food, serum (▴) or rCT-1 (10 μg/ml) (Δ) was administered by intravenous route. The results (
Then, it was investigated if treatment with rCT-1 accelerated the elimination of free fatty acids in serum after an intralipid injection. To do this, rCT-1 was administered intravenously to two groups of animals (n=5) 30 minutes after administration of intralipids. The control animals received saline. The concentration of free fatty acids in serum was determined after 5 minutes. Then, the elimination values of the free fatty acids taken at different times were normalized with respect to the FFA values 5 minutes after the injection of intralipids (100%). As shown in
In order to determine the possible effects of rCT-1 on beta oxidation, the oxidation of palmiate in gastrocnemius muscle isolated from mice treated with saline or with CT-1 (10 μg for 1h) was determined The results (
Skeletal muscle is the most sensitive tissue to insulin action and provides in healthy individuals for 90% of glucose uptake stimulated by insulin. The authors have shown that CT-1 enhances insulin signaling in muscle “in vitro” and “in vivo”.
The experiments “in vitro” were carried by measuring insulin-induced 2-deoxyglucose uptake and AKT phosphorylation in rat myotubes (L6E9 myoblasts differentiated to myotubes) after acute (1 hour) or chronic treatment (24 hours) with rCT-1. It was observed that CT-1 stimulates insulin-induced 2-deoxyglucose uptake (
Moreover, it was observed “in vivo” that intravenous administration of rCT-1 (10 μg/mouse) 30 minutes before insulin stimulation (0.5 U/mouse injected into the inferior cave vein) increased insulin-induced AKT phosphorylation in muscle (
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-000396 | Feb 2009 | ES | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/ES2010/070072 | 2/10/2010 | WO | 00 | 8/12/2011 |
