Methods of Identifying Candidate Compounds of the Human G Protein-Coupled Receptor, GPR50, as Modulators of Body Mass or Adiposity

Abstract

The present invention relates to methods of using a G protein-coupled receptor (GPCR) to screen one or more candidate compounds as a modulator of body mass or of adiposity or of percentage body fat in a subject or as a pharmaceutical agent for obesity and conditions related thereto. Inverse agonists and antagonists of the invention are useful as therapeutic agents for the prevention or treatment of obesity and conditions related thereto, including hypertension, insulin resistance, metabolic syndrome, Type 2 diabetes, dyslipidemia, atherosclerosis, coronary heart disease, and stroke. Agonists and partial agonists of the invention are useful as therapeutic agents for the prevention or treatment of disorders ameliorated by increasing body mass including, but not limited to, cachexia.

1 - 72 . (canceled) 
     
     
         73 . A method of identifying a candidate compound as a modulator of body mass in a mammal or a modulator of adiposity in a mammal, comprising the steps of:
 (a) contacting the candidate compound with a G protein-coupled receptor (GPCR) comprising an amino acid sequence having at least 80% identity to SEQ ID NO: 2; wherein the receptor couples to a G protein; and   (b) determining the ability of the compound to inhibit or stimulate functionality of the GPCR;   wherein the ability of the compound to inhibit or stimulate functionality of the GPCR is indicative of the compound being a modulator of body mass in a mammal or a modulator of adiposity in a mammal.   
     
     
         74 . A method of identifying a candidate compound as an agent for treating or preventing obesity or a condition related thereto, comprising the steps of:
 (a) contacting the candidate compound with a G protein-coupled receptor (GPCR) comprising an amino acid sequence having at least 80% identity to SEQ ID NO: 2; wherein the receptor couples to a G protein; and   (b) determining the ability of the compound to inhibit functionality of the GPCR;
 wherein the ability of the compound to inhibit functionality of the GPCR is indicative of the compound being an agent for treating or preventing obesity or a condition related thereto. 
   
     
     
         75 . The method of  claim 74 , further comprising,
 (c) administering a compound which inhibits functionality of the GPCR in step (b) to a mammal; and   (d) determining whether the compound confers protection from weight gain in the mammal,   wherein the ability of the candidate compound to confer protection from weight gain in the mammal is indicative of the candidate compound being an agent for treating or preventing obesity or a condition related thereto.   
     
     
         76 . The method of  claim 74 , wherein the method comprises detecting a second messenger. 
     
     
         77 . The method of  claim 74 , wherein said determining is by a process comprising the use of a melanophore assay or by a process comprising the measurement of GTPγS binding to a membrane comprising the GPCR. 
     
     
         78 . The method of  claim 74 , wherein said contacting of the candidate compound with a GPCR comprises contacting the candidate compound with a eukaryotic host cell comprising the GPCR or with membrane thereof that comprises the GPCR. 
     
     
         79 . The method of  claim 74 , wherein the method further comprises formulating said compound as a pharmaceutical composition. 
     
     
         80 . A compound that modulates a GPCR comprising an amino acid sequence having at least 80% identity to SEQ ID NO: 2, wherein said compound is identified using the method of  claim 74 . 
     
     
         81 . A pharmaceutical composition comprising the compound of  claim 80  and a pharmaceutically acceptable carrier. 
     
     
         82 . The pharmaceutical composition of  claim 81 , further comprising a second pharmaceutically active agent. 
     
     
         83 . A method of treating or preventing obesity or conditions related to obesity comprising administering the pharmaceutical composition of  claim 81 . 
     
     
         84 . The method of  claim 83 , wherein the condition related to obesity is selected from the group consisting of hypertension, insulin resistance, metabolic syndrome, Type 2 diabetes, dyslipidemia, atherosclerosis, coronary heart disease, and stroke. 
     
     
         85 . A method of identifying a candidate compound as an agent for preventing or treating a disorder ameliorated by increasing body mass in a mammal, comprising the steps of:
 (a) contacting the candidate compound with a G protein-coupled receptor (GPCR) comprising an amino acid sequence having at least 80% identity to SEQ ID NO: 2; wherein the receptor couples to a G protein; and   (b) determining the ability of the compound to stimulate functionality of the GPCR;   wherein the ability of the compound to stimulate functionality of the GPCR is indicative of the compound being an agent for preventing or treating a disorder ameliorated by increasing body mass in a mammal.   
     
     
         86 . The method of  claim 85 , further comprising,
 (c) administering a compound which stimulates functionality of the GPCR in step (b) to a mammal; and   (d) determining whether the compound increases body mass in the mammal,   wherein the ability of the candidate compound to increase body mass in the mammal is indicative of the candidate compound being an agent for preventing or treating a disorder ameliorated by increasing body mass in a mammal.   
     
     
         87 . A compound that modulates a GPCR comprising an amino acid sequence having at least 80% identity to SEQ ID NO: 2, wherein said compound is identified using the method of  claim 85 . 
     
     
         88 . A pharmaceutical composition comprising the compound of  claim 87  and a pharmaceutically acceptable carrier. 
     
     
         89 . The pharmaceutical composition of  claim 88 , further comprising a second pharmaceutically active agent. 
     
     
         90 . A method of preventing or treating a disorder ameliorated by increasing body mass in a mammal, comprising administering the pharmaceutical composition of  claim 88 . 
     
     
         91 . The method of  claim 90 , wherein the disorder ameliorated by increasing body mass is selected from the group consisting of cachexia, wasting, AIDS-related weight loss, cancer-related weight loss, anorexia, and bulimia. 
     
     
         92 . A method of identifying a candidate compound as a modulator of body mass in a mammal or as a modulator of adiposity in a mammal, said method comprising the steps of:
 (a) providing a transgenic non-human mammal comprising a disruption in an endogenous GPR50 gene wherein the transgenic non-human mammal lacks production of functional GPR50 protein and exhibits, relative to the wild-type, a decreased weight gain induced by a high fat diet;   (b) administering the candidate compound to the transgenic non-human mammal; and   (c) determining whether the decreased weight gain induced by a high fat diet is modulated by the candidate compound, thereby identifying the candidate compound as a modulator or body mass in a mammal or as a modulator of adiposity in a mammal.