Apoptosis: Insight into Stages, Extrinsic and Intrinsic Pathways
Background: Apoptosis is a vital process for normal cell turnover, proper development and functioning of the immune system, embryonic development and chemical-induced cell death. Objectives: The present review aims to spotlight on the stages and mechanisms of programmed cell death. Apoptosis, known as programmed cell death, is a homeostatic mechanism that generally occurs during development and aging in order to keep cells in tissue. It can also act as a protective mechanism, for example, in immune response or if cells are damaged by toxin agents or diseases. In cancer treatment, drugs and irradiation used in chemotherapy leads to DNA damage, which results in triggering apoptosis through the p53 dependent pathway in cancer treatment, drugs and irradiation used in chemotherapy leads to DNA damage, which results in triggering apoptosis through the p53 dependent pathway. Corticosteroids can cause apoptotic death in a number of cells. A number of changes in cell morphology are related to the different stages of apoptosis, which includes nuclear DNA fragmentation, cell shrinkage, chromatin condensation, membrane blebbing, and the formation of apoptotic bodies. There are three pathways for apoptosis, the intrinsic (mitochondrial) and extrinsic (death receptor) are the two major paths that are interlinked and that can effect one another. Conclusion: It can be concluded that apoptosis is a homeostatic mechanism that generally occurs during development and aging in order to keep cells in tissue. Drugs and irradiation used in chemotherapy leads to DNA damage, which results in triggering apoptosis through the p53 dependent pathway. The apoptosis, stages are includes nuclear DNA fragmentation, cell shrinkage, chromatin condensation, membrane blebbing, and the formation of apoptotic bodies. There are three pathways for apoptosis.
Apoptosis, Stages of Apoptosis, Extrinsic Pathway, Intrinsic Pathway, Mechanisms of Apoptosis
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