cell injury and cell death -...

CELL INJURY and CELL DEATH: Part 1

Jhia Anjela D. RiveraDepartment of Biological SciencesSchool of Science and TechnologyCentro Escolar University

CELL INJURY

A sequence of events that occur if the limits of adaptive capability are exceeded or no adaptive response is possible.

Causes:

• Ischemia

• Hypoxia

• Chemical injury and;

• Injury produced by infectious agents

CELL INJURY: Ischemia

Deficient supply of blood to a body part that is due to obstruction of the inflow of arterial blood

CELL INJURY: Hypoxia

Oxygen deficiency (reaching the tissues of the body)

CELL INJURY: Chemical Injury

Exposure or intake of chemicals

CELL INJURY: Infectious Agents

Bacteria, Virus etc.

CELL INJURY OVERVIEW

NORMAL CELL

MECHANISMS OF CELL INJURY

1) Depletion of ATP2) Mitochondrial Damage3) Influx of Intracellular Calcium and Loss of Calcium

Homeostasis4) Accumulation of Oxygen-Derived free radical (Oxidative

stress)5) Defects in Membrane Permeability

CELL INJURY• Reversible Injury• Cell swelling develops when cells are incapable of fluid

an ion homeostasis (↓ function of ATP dependent pumps).

• Irreversible injury (Necrosis)o Two basic processes underlie the morphologic changes of

necrosis1) Denaturation of protein2) Enzymatic digestion of cell components

CELL INJURY AND CELL DEATH

CELL INJURY AND CELL DEATH