APOPTOSIS
By DR; SNT

APOPTOSIS
 apoptosis is defined as the pathway of cell death that is induced by
a tightly regulated suicidal program in which cell distinate to die
active intrinsic enzyme that degrade the cell on its nuclear DNA and
the nuclear and cytoplasmic proteins .

Characteristics
 1. apoptotic sale break into the small bodies fragments called
the apoptotic bodies
 2. integrity of cell is maintained does there is no licking of cell
 3. however the structure is changed but the the plasma membrane
remain intact.
 4. however it is also said to be the genetically programmed cell
death.


CAUSES OF APOPTOSIS
 normally both during the growth and development throughout the
adulthood and serves to remove the unwanted aged or potentially
harmful cells. it may also be the pathological event when the
diseased cells are damage during their repair repair.

physiological
 Death of cell by the normal phenomenon during the growth and
development and unwanted use of tissues
 1. during embryogenesis organogenesis implantation development
station metamorphosis….
 2.host cell served as a useful function example neutrophils in the
acute inflammation lymphocyte at the end of immune response.
 3. Cells loss in poliferating the cell population (example thymus)
 4.involution of hormones -dependent issue on hormone withdrawal
for example during the mensuration breakdown of the
endrometrium cell
 5. eliminationof potentially harmful self reactive lymphocytes that
action organised on tissue.


PATHOLOGICAL:
 begins in those cells in which there is no chance of
repair.due to following condition
 1. DNA damage; during the sunlight UV range injury
hypoxia ischemia
 2. regulation of the Miss World protein this lead to the
year status which culminates in apoptotic cell.
 3. cell death in certain infection due to theparticularly
 viral infection .
 4. pathological atrophy internal organs after the duct
obstruction surgery in pancreas parotid gland kidney


MORPHOLOGY
 1 .cell shrinkage
 2. chromatin condensation most characteristic
feature of apoptosis
 3. formation of cytoplasmic bulb and apoptotic
bodies
 4. phagocytosis of apoptotic cells by the
macrophages generall


MORPHOLOGY
 result from the activation of enjoying called caspase
 the mechanism of apoptosis is generally classified into
two pages that is initiation phase and the execution
phase
 in the initiation phase there is a production of som
catalytic caspase where in the execution phase there is
the destruction that is triggered by by those caspase by
converting into the education caspases

there are two different pathway for the caspase
activation
 1first is the mitochondrial pathway
 2 the death receptor pathway


 1the mitochondrial pathway is a major mechanism of
apoptosis in the mammalian cell it results from the increase in
permeability of mitochondrial outer membrane with the
consequent release of death inducing proapoptotic bodies
molecules from the mitochondria intramembranous space into
the cytoplasm

growth factors and other for survival signal stimulate the
production of antiapoptotic bodies such as bcl2to prevent
leakage of death inducing proteins from mitochondrial outer
membrane

step 1; as soon as the living signal is not received
 step 2 DNA damage and protein start to miss fold
and endoplasmic reticulum get stress
 step 3; this signal is received by only the Bh3

 step 4 this Bh3 protein activates the the two protein call
back and bags that are responsible for the production of
pro-apoptotic bodies
 step 5; they form an oligomer and enter the
mitochondrial membrane and there is a leakage of
mitochondrial protein include in the the cytochrome C
with its harmful. bh3 protein also prevent function of
bcl2.
 step 6; the cytochrome C is released in the sight of it
combined with the APAF1( Activating factor 1) which
formed apoptosome.
 step 7; this is the first initiator factor for the caspase
activation later on cleavage occurs does the capapsaes
are more active .


 death receptor pathway
 Is initiated by the engagement of plasma
membrane with receptor on the variety of cells
 receptor are the membranes of tnf receptor family
 this tnf1 receptor related protein call the fas
 the ligand for the fas is called the fas legend


 when the first ligand binding to the fast two three
molecules of pass are brought together and their
cytoplasmic date domains a binding site for adaptor
protein that that also consists of death domain called f
a DD it is attached to the inactive 8,10 and multiple
procaspase of its are formed by the cleavage
 execution phase
 this profound caspase 8 9 and 10 in the initiation phase
are converted into the The executive caspase 3 and 6
that are responsible for promote fragmentation of nuclei
degrade the structural component of nuclear Matrix and
act on the cellular component and the in Activator of
cytoplasmic DNase


REMOVAL OF DEAD CELL
 some chemicals are expressed on the outer
membrane of the apoptotic cell
 dying cells secrete soluble factors special
chemicals that has a recognised by the phagocytes
the cells are by the process of apoptosis in the
minute period of time
