What is the evidence for different functional populations of mitochondria in adipocytes?

Abstract

Background: Mitochondria in adipocytes regulate whole-body energy homeostasis, significantly influencing insulin sensitivity and glucose metabolism. Mammalian adipocytes are classified into white (WAT) and brown (BAT) adipocytes. BAT contains many mitochondria, which heat production and energy expenditure. WAT contains fewer mitochondria, but they play an important role in metabolic homeostasis. Dysregulated mitochondrial function may contribute to metabolic disorders such as obesity and T2DM. Understanding the distinct mitochondrial populations is crucial for comprehending these diseases. This research aims to investigate the presence of distinct groups of mitochondria within adipocytes and test the potential effect of insulin on the attachment of mitochondria to lipid droplets. The hypothesis tested was that these different populations of mitochondria have different biological functions in adipocytes. Method: A comprehensive search across various databases used multiple primary keys to identify five relevant primary articles to the research question. Results: The findings from several studies indicate the existence of diverse mitochondrial groups (PDM and CM) within adipocytes that were shown to have unique functions for these isolated mitochondria compared to those in the cytosol. The function of mitochondria may be affected by several external factors, such as exposure to cold and some pharmacological treatments, which may, therefore, affect its function in terms of energy production and the formation of triglycerides. Conclusion: Despite the current body of evidence, there remains a lack of sufficient support to conclusively establish distinct mitochondrial sites and the potential role of insulin in their association with lipid droplets. Therefore, there is a need for more extensive and comprehensive experimentation to address these research gaps.