Author/Authors :
beikzadeh، babak نويسنده urmia university beikzadeh, babak , Delirezh، Nowruz نويسنده Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Iran ,
Abstract :
Cells are active components in their environment and
constantly adjusting their performance to improve
extracellular milieu changing. This approach is
reflected their tends of maintaining intracellular
homeostasis. When the cells encounter stress or
pathologic stimuli, they can undergo a new manner
(adaptation) and new steady state for achieving
viability and function. If the external stress is
exceeded or adaptive capability continues, cell injury
develops (1, 2). Cells injury is engaged in a process
that is reversible or irreversible. Injury is reversible
when the stimuli are limited and removed. Only in
the persistent stress or pathologic stimuli a reversible
phase converted into irreversible phase (point-of-noreturn)
and causes cell death(3). However, cell death
is the most important step in embryogenesis, organ
development, hemostasis and also the evolution of
disease in any organ (1). The most classifications of
mammalian cell death are apoptosis and necrosis.
Apoptosis occurs naturally in many situations and
helps to eliminate the cells that lost their efficiency.
Cells undergoing apoptosis show biochemical events
lead to cell changes (morphology) and death (4, 5).
These features include cell blebbing, shrinkage,
chromatin condensation and nuclear fragmentation.
Unlike necrosis, which is a pathologic cell death,
apoptotic cells release cell fragment called apoptotic
bodies (1, 6). This image was taken with light
microscopes (Nikon, TE2000 inverted microscopes),
peripheral blood monocytes during 13 days culture
initially change into macrophage-like cells and then
due to lack of nutrition materials and a high level of
toxic substance, to undergo cell death. The
morphological changes as mention above (Fig1
legend) approved apoptosis process and cell death.
However, sometimes the end stage of apoptosis
accompanied by necrosis and it is not possible to
distinguish them from the microscopic view.