Research Of Ins2 Lineage Cells Tracing And The Expression Of Insulin

Background:Diabetes mellitus has become the third major cause of morbidity and mortality after cancer and cardiovascular disease,and it is a common metabolic disease in adults.Diabetes is a chronic metabolic disease with the main symptom of insufficient insulin secretion.In the field of Stomatology,diabetes and oral diseases have been recognized as one of the diseases which could affect each other.Insulin has been widely concerned because of its close relationship with the blood glucose level.Insulin is a protein hormone secreted by islet beta cells in the pancreas stimulated by endogenous or exogenous substances.Insulin is the only hormone that can lower blood sugar in the body,which plays an important role in our growth and development.In recent years,in order to study the function of insulin related genes in the synthesis and secretion of insulin,the researchers constructed a variety of transgenic mice including Tg(Ins2-cre)25Mgn,and they found that ins2-cre is expressed not only in the pancreas but also expressed in other endocrine regulation organization.These findings suggested that the expression of ins2-cre is not confined to the beta cells of the pancreas,but also in a variety of tissues and organs.However,there is still lack of a comprehensive and detailed study on the overall distribution of the ins2 cell lineage in the animal.Cell lineage tracing is a kind of animal tracing technology to some specific cells in the body.It is a new biological technology which we can mark some particular cells in the early stages of animal development so that we can use the detecting markers to study the migration and alteration of labeled cells after a period of time.This technique has the advantage of simple and intuitive,and it can be used to identify and trace the cells under the prerequisite of ensuring the survival of cells.So this technique has become one of the most important tools to study cell and developmental biology.By using the Cre /loxp system to label the cells,the specific cell populations and their progeny will be carried with some particular reporter protein,which can be used to study the migration and differentiation of specific cell populations efficiently.In this study,we will use Cre/Loxp site-specific recombination system to trace Ins2 cell lineage in mice;we will use this system to study the role of Wnt/ beta-catenin signaling pathway in the migration and fate determination of Ins2 cell lineage and explore the presence of insulin in these cells.Objective:To get the distribution maps of Ins2-cre lineage cells in mice.To explore the role of Wnt/ beta-catenin signaling pathway in its development.To detect the presence of insulin in Ins2-cre lineage cells.To detect the presence and secretion of insulin in submandibular gland under the stress conditions.Methods:1.Cre /loxp system was used to label the cells and observe the migration sites and time of Ins2-cre lineage cells.2.Study the role of Wnt/ beta-catenin signaling pathway in the migration and differentiation of Ins2 lineage cells by analyzing the beta-catenin knockout mice3.The presence of insulin in Ins2-cre lineage cells was detected by immunohistochemistry and immunofluorescence.4.We will establish animal models of stress-induced hyperglycemia in mice,and detect the secretion of insulin in submandibular gland under the hyperglycemic state.Results:1.We successfully find the migration of Ins2-cre lineage cells in adult mice: including pancreas,submandibular gland,brain.We established a comprehensive mapping of Ins2-cre lineage cells in multiple developmental periods in adult mice.2.We get the completely loss of function of beta-catenin mice by mating and screening.We successfully observed the onset time of Ins2-cre lineage cells in beta-catenin knock-out mice: the cells will appear from the embryonic day 9.5(E9.5)until adulthood.The migration sites of mouse ins2-cre cell lineage increase,mainly including the pancreas,submandibular gland,tongue,the upper jaw,tongue,teeth and hypophysis.3.We found the expression of insulin-positive cells in the Ins2-cre lineage cells.4.We successfully established hyperglycemia animal model of stress state of mice,and we detect the secretion insulin of the submandibular gland.Conclusion:Ins2 lineage cells can migrate to multiple organs and tissues in mice,and there may have insulin in these tissues;Wnt/ beta-catenin signaling pathway may decrease the migration sites of Ins2 lineage cells;Submandibular glands may secrete insulin in response to stress in order to maintain the homeostasis of organism.