Apoptosis, or programmed cell death, is a vital process influenced by a variety of internal and external factors. Many things can trigger or inhibit this crucial cellular mechanism.
Internal Factors Affecting Apoptosis
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Cellular Damage: Oxidative damage, DNA damage, and other forms of cellular stress can initiate apoptosis. The cell recognizes irreparable damage and triggers self-destruction to prevent harm to the organism. [Reference: What Triggers Apoptosis? Stress such as radiation or chemical exposure can trigger apoptosis, scientists have determined, as can infection, or oxidative damage.]
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Protein Signaling: Internal protein signaling pathways, such as those involving PTEN, play a crucial role in regulating apoptosis. Dysregulation of these pathways can lead to uncontrolled cell growth or excessive cell death. [Reference: PTEN affects cell size, cell proliferation and apoptosis during...]
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Mitochondrial Function: The mitochondria, often referred to as the cell's powerhouses, play a key role in apoptosis. Damage or dysfunction of the mitochondria can trigger the apoptotic cascade. [Reference: Infrared radiation affects the mitochondrial pathway of apoptosis in ...] & [Reference: Loss of apoptosis-inducing factor critically affects MIA40 function ...]
External Factors Affecting Apoptosis
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Environmental Stressors: Exposure to radiation, certain chemicals, or other environmental stressors can initiate apoptosis. The intensity of the stressor often dictates the type of cell death (apoptosis or necrosis). [Reference: Apoptosis: A Review of Programmed Cell Death - PMC. In some cases it's the type of stimuli and/or the degree of stimuli that determines if cells die by apoptosis or necrosis. At low doses, a variety of injurious...]
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Infections: Infections can also induce apoptosis as a defense mechanism. For instance, certain bacteria like Fusobacterium nucleatum can manipulate cellular processes to promote their own survival and potentially cause disease. [Reference: Fusobacterium nucleatum Affects Cell Apoptosis by Regulating ...]
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Growth Factors and Hormones: External signals like growth factors and hormones can either promote or inhibit apoptosis. For example, the type of beta-adrenergic receptor involved can influence apoptosis in certain cell types. [Reference: Extracellular Control of Cell Division, Cell Growth, and Apoptosis ...] & [Reference: β-Adrenergic Receptor Subtypes Differentially Affect Apoptosis in ...]
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Hyperglycemia: External factors such as high blood sugar levels (hyperglycemia), as seen in maternal diabetes, can induce higher levels of apoptosis in specific cell types. [Reference: Maternal Diabetes Adversely Affects Preovulatory Oocyte Maturation ...]
Types of Cell Death
It's important to note that apoptosis is one of several types of cell death. Necrosis, for example, is a form of cell death caused by injury or damage, and autophagy is a cellular self-cleaning process that can also contribute to cell death. [Reference: Cell Death: Causes, Apoptosis, Autophagy & Necrosis]
