Reference number : GC-2017-Q1-02892, amendment number : , agreement type : G, recipient legal name : Tchernof, Andre (Université Laval), recipient country : CA, recipient province : nan, recipient city : Quebec|Québec, recipient postal code : nan, program name english : Discovery Grants Program - Individual, program name french : Programme de subventions à la découverte - individuelles, program purpose english : This NSERC Discovery program was initially funded in 2011. The renewal proposal submitted in 2015 was awarded one year of funding. The present application offers a revised project taking into account the constructive comments made by Reviewers. 
 
Our General Objective is to further characterize the dedifferentiation process of mature adipocytes toward fibroblast-like cells using the ceiling culture approach, with a focus on causal agents of this phenomenon. The experiments proposed represent a direct and logical extension of the results obtained in the first term of the grant. Specifically, the projects described below follow our development of a six-well plate, non-hypoxic ceiling culture approach and time-lapse microscopy, as well as our discoveries on the potential role of matrix-remodelling factors such as Transforming growth factor &beta; (TGF&beta;), Fibroblast-activation protein &alpha; (FAP) and Dipeptidyl peptidase IV (DPP4) in the process of adipocyte dedifferentiation. We propose four Specific Aims, each representing a specific project. 
 
 Specific Aim #1: To address uncertainty regarding the issue of contaminating mesenchymal cells that may be present with isolated mature adipocytes undergoing dedifferentiation in ceiling cultures. We will isolate mature adipocytes from a mouse strain overexpressing GFP specifically in mature adipocytes, and monitor dedifferentiation in vitro . We will also test the impact of cell suspension washing, cell suspension centrifugation and inhibitors of cell proliferation. 
 
 Specific Aim #2: To characterize the role of TGF-&beta; in the process of adipocyte dedifferentiation. We will isolate mature adipocytes from a mouse strain deficient in TGF-&beta;1 signalling and monitor cell dedifferentiation in vitro . TGF-&beta;1 will also be used in conjunction with pharmacological inhibitors. 
 
 Specific Aim #3: To characterize the role of FAP in the process of adipocyte dedifferentiation. Pharmacological inhibitors of FAP as well as adipocytes isolated from Fap-deficient mice will be used to establish and characterize the importance of this enzyme for dedifferentiation in ceiling cultures. 
 
 Specific Aim #4: To characterize the role of DPP4 in the process of adipocyte dedifferentiation. Pharmacological inhibitors of DPP4 as well as adipocytes isolated from Dpp4-deificent mice will be used to establish and characterize the importance of this enzyme in adipocyte dedifferentiation in ceiling cultures. 
 
Most research groups working in this area focus mainly on the cells generated by the dedifferentiation process, not on the transformation itself. We propose that a better understanding of the drivers or inhibitors of this process, along with improved culture techniques, would greatly facilitate the use of dedifferentiated adipocytes in the tissue engineering realm. The techniques developed will contribute to HQP training and provide new models for studies on adipocyte biology., program purpose french : This NSERC Discovery program was initially funded in 2011. The renewal proposal submitted in 2015 was awarded one year of funding. The present application offers a revised project taking into account the constructive comments made by Reviewers. 
 
Our General Objective is to further characterize the dedifferentiation process of mature adipocytes toward fibroblast-like cells using the ceiling culture approach, with a focus on causal agents of this phenomenon. The experiments proposed represent a direct and logical extension of the results obtained in the first term of the grant. Specifically, the projects described below follow our development of a six-well plate, non-hypoxic ceiling culture approach and time-lapse microscopy, as well as our discoveries on the potential role of matrix-remodelling factors such as Transforming growth factor &beta; (TGF&beta;), Fibroblast-activation protein &alpha; (FAP) and Dipeptidyl peptidase IV (DPP4) in the process of adipocyte dedifferentiation. We propose four Specific Aims, each representing a specific project. 
 
 Specific Aim #1: To address uncertainty regarding the issue of contaminating mesenchymal cells that may be present with isolated mature adipocytes undergoing dedifferentiation in ceiling cultures. We will isolate mature adipocytes from a mouse strain overexpressing GFP specifically in mature adipocytes, and monitor dedifferentiation in vitro . We will also test the impact of cell suspension washing, cell suspension centrifugation and inhibitors of cell proliferation. 
 
 Specific Aim #2: To characterize the role of TGF-&beta; in the process of adipocyte dedifferentiation. We will isolate mature adipocytes from a mouse strain deficient in TGF-&beta;1 signalling and monitor cell dedifferentiation in vitro . TGF-&beta;1 will also be used in conjunction with pharmacological inhibitors. 
 
 Specific Aim #3: To characterize the role of FAP in the process of adipocyte dedifferentiation. Pharmacological inhibitors of FAP as well as adipocytes isolated from Fap-deficient mice will be used to establish and characterize the importance of this enzyme for dedifferentiation in ceiling cultures. 
 
 Specific Aim #4: To characterize the role of DPP4 in the process of adipocyte dedifferentiation. Pharmacological inhibitors of DPP4 as well as adipocytes isolated from Dpp4-deificent mice will be used to establish and characterize the importance of this enzyme in adipocyte dedifferentiation in ceiling cultures. 
 
Most research groups working in this area focus mainly on the cells generated by the dedifferentiation process, not on the transformation itself. We propose that a better understanding of the drivers or inhibitors of this process, along with improved culture techniques, would greatly facilitate the use of dedifferentiated adipocytes in the tissue engineering realm. The techniques developed will contribute to HQP training and provide new models for studies on adipocyte biology., agreement title english : Adipocyte dedifferentiation in the ceiling culture system: regulators of cell matrix remodelling, agreement title french : Adipocyte dedifferentiation in the ceiling culture system: regulators of cell matrix remodelling, agreement number : RGPIN, agreement value : 140000.0, agreement start date : 2017-05-10, agreement end date : nan, description english : nan, description french : nan, expected results english : nan, expected results french : nan, additional information english : Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023), additional information french : Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier. (2017-2018 à 2022-2023), owner organization : nserc-crsng, owner organization title : Natural Sciences and Engineering Research Council of Canada | Conseil de recherches en sciences naturelles et en génie du Canada