Cell death is a complex process with multiple mechanisms, each playing a crucial role in development, tissue homeostasis, and disease. There are both regulated and unregulated forms.
Regulated Cell Death (RCD)
Regulated cell death (RCD) involves dedicated molecular pathways, often controllable through genetic or pharmacological means. Several key types exist:
1. Apoptosis: Programmed Cell Death
Apoptosis is a highly regulated, programmed form of cell death essential for development and eliminating damaged cells. It's characterized by distinct morphological changes. There are two primary pathways:
- Extrinsic Pathway (Death Receptor Pathway): Initiated by external signals binding to death receptors on the cell surface.
- Intrinsic Pathway (Mitochondrial Pathway): Triggered by internal stress, leading to mitochondrial dysfunction and release of pro-apoptotic factors. This is the most common apoptosis mechanism in vertebrates. (Cell Death Signaling, Apoptosis: A Review of Programmed Cell Death, Mechanisms of Cell Death: Apoptosis)
2. Other Regulated Cell Death Mechanisms
Besides apoptosis, other forms of regulated cell death include:
- Necroptosis: A programmed necrosis-like cell death involving necroptosome formation. (Die another way – non-apoptotic mechanisms of cell death)
- Pyroptosis: An inflammatory form of programmed cell death triggered by infection. It's characterized by the formation of pores in the cell membrane, leading to cell swelling and lysis. (Different types of cell death and their shift in shaping disease, Bacterial gasdermins reveal an ancient mechanism of cell death)
- Autophagy: A self-eating process where cells degrade their own components. It can contribute to cell death under certain circumstances. (Types of Cell Death: Apoptosis, Autophagy, and Necrosis, Different types of cell death and their shift in shaping disease)
Unregulated Cell Death (Necrosis)
Necrosis is a form of cell death characterized by uncontrolled cell swelling and membrane rupture, often resulting from injury or infection. Unlike apoptosis, it is typically not a regulated process.
The Nomenclature Committee on Cell Death (NCCD)
The NCCD provides recommendations for classifying and defining different types of cell death, focusing on mechanistic aspects. (Molecular mechanisms of cell death: recommendations of the)
