Biochemical mechanisms of toxic cell injury

Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...

Bioactivation is a metabolic process that transforms less reactive substances into highly reactive metabolites, initiating tissue toxicity. This transformation can lead to various toxic effects, including carcinogenesis and teratogenesis. Reactive metabolites are classified into two main types: electrophiles and free radicals.Electrophiles are electron-deficient species and are produced primarily by the enzyme cytochrome P-450 during the metabolism of compounds containing carbon, nitrogen, or...

Cellular injury occurs when a cell cannot maintain homeostasis or adapt to stressors such as hypoxia, toxins, or trauma. Depending on severity and duration, injury may be reversible, allowing recovery, or irreversible, leading to cell death.General Mechanisms of Cell InjuryAlthough causes vary, most cellular injuries arise from a few key mechanisms that disrupt essential functions and often amplify one another. Cell survival depends on the extent and balance of these disturbances.ATP depletion...

Cellular injury is any process that disrupts a cell’s ability to maintain homeostasis, leading to structural or functional changes. It is broadly classified based on etiology (cause) and mechanism of damage.Classification by EtiologyCellular injury may result from several causes. Hypoxic injury happens due to reduced oxygen delivery, most commonly from inadequate blood supply, such as arterial obstruction; for example, coronary artery thrombosis can cause myocardial infarction. Chemical injury...

Cell death is the irreversible loss of cellular structure and function, representing the final stage of severe injury. It plays a key role in both normal physiology and disease.Types of Cell DeathThe two main types are necrosis and apoptosis, though others like necroptosis and pyroptosis also exist.Necrosis:Necrosis is an unregulated form of cell death caused by severe injury such as trauma, toxins, or ischemia. It is characterized by cell swelling, membrane loss, rupture, and leakage of...

Necrosis is a form of irreversible cell death caused by severe injury such as ischemia, toxins, or trauma. Unlike programmed cell death, it is an uncontrolled, pathological process that typically provokes inflammation in surrounding tissues.Pathophysiologic ChangesNecrosis begins when cells sustain critical damage, leading to swelling of organelles, particularly mitochondria, and rapid ATP depletion. As energy levels decline, membrane ion pumps fail, leading to calcium influx and eventually,...