intrinsic and extrinsic pathway of apoptosis, mitochondrial pathway, caspases,

1. Apoptosis Dr Sehrish Ahmed

2. Apoptosis
A form of cell death in which a programmed sequence of
events leads to the elimination of cells without releasing
harmful substances into the surrounding area.
Therefore does not elicit inflammatory reaction

5. Causes of
Apoptosis
Physiologic pathologic

6. physiologic situations

7. Involution of hormone dependent tissues

9. Death of host cells that have served their useful purpose

10. Apoptosis in pathologic
conditions
DNA Damage
Accumulation of Misfolded
proteins
Cell injury in certain infections
Pathologic atrophy in parenchymal
organs after duct obstruction

11. Mechanism of Apoptosis
Intrinsic pathway :the
cell kills itself
because it senses cell
stress,
Extrinsic pathway the
cell kills itself
because of signals
from other cells.

12. Main executors of the apoptotic process is . . ?
• CASPASES
• They stands for Cysteine
Aspartate-specific Protease
• Synthesized as inactive zymogens
(PROCASPASES)

15. 1. Withdrawal of survival
factors
2. Direct mitochondrial
3. ER stress
4. p53-mediated
5. Viruses
BH3
SENSORS

18. Effector Caspases
Initiator Caspases

24. DEATHRECEPTORPATHWAY

26. Clearance of
Apoptotic
Cells

27. Examples of Apoptosis

28. Growth Factor
Deprivation

29. DNA Damage

30. Accumulation of Misfolded Proteins: ER Stress

31. Apoptosis of
Self-Reactive
Lymphocytes
Lymphocytes capable of recognizing self
antigens are normally produced in all
individuals.
If these lymphocytes encounter self
antigens, the cells die by apoptosis.
Both the mitochondrial pathway and the
Fas death receptor pathway
Failure of apoptosis of self-reactive
lymphocytes is one of the causes of
autoimmune diseases.

35. Thankyou!