University:
Dartmouth College
Course:
BIOL 51 | Human Anatomy and Physiology
Academic year:

2023
Views:

126

Pages:

5
Author:

pennu4565

ApoptosisAPOPTOSIS00:10Programmed cell deathActivation of intrinsic enzymes by programming to formfagmented cells called Apoptotic BodyApoptotic Bodies are engulfed by macrophagesCAUSES of APOPTOSIS02:15PhysiologicalDuring embryogenesisCells during organogenesis.Hormonal withdrawalEndometrial cell breakdown during . menustrual cycleRemoval of self reactive lymphocytesmenopauseIn thymus (Central tolerance)Post inflammatory responceexcess inflammatory cells are removed. PathologicalDNA Damaged by Radiotherapy, Chemotherapy, HypoxiaAccumulation of misfolded proteinCell death in viral infection. Eg : HIV, Hepatitis virus.In organ due to ductal obstruction Eg:- Parotid glandPancreas.MECHANISM of APOPTOSIS10:15Intrinsic pathwayExtrinsic pathway(Mitochondria)(Death /FAS Receptor)Cell suicideProgrammed cell murderCell injury :-FIRST APOPTOTIC SIGNALGrowth Factor withdrawalRadiationFAS (TNF-R or CD95)InteractProtein misfoldingFAS Ligand (TNF)Sensed byFADDApoptotic sensors BH3 only proteinsFas associated death domain[Have 3rd BH Domain protein)+BIM, BID, BAD, NOXA, PUMACaspase 8Antiapoptotic geneProapoptotic gene Antiapoptotic geneProapoptotic geneCaspase 8(Have 4BH domain)(Have 3 BH domains)BCL- - 1,2BCL- XLBAXMCLBAKL= Long lifemitochondrial permeabilityInitiatorCytochrome C comes outCaspaseApoptosome activates Caspase DCytochrome CAPAR-1Apoptosis acti.Factor 1Initiator Caspase (Caspase 8&9)ActivateExecutional caspase 3,6+EndonucleaseCytoskeleton Protein breakdownApoptotic BodyApoptotic Body seperates from main cellRemoved by macrophage Cell InjuryFASFAS LigandCaspase 8BH3Caspase 9anti- apoptoticProapop+genetotic gene>poptosomeCaspase 36BLC 1,2BAXBLC XLMCLBAKEndonucleaseCytoskeleton(Nucleus)BreakdownMacrophageBlebPhosphatidy) serireNuclear frag mentsApoptotic BodyOrganellesRECOGNITION OF APOPTOTIC BODY BY MACROPHAGEThrough EAT ME SignalFliping out of Phosphatidyl Serine on membrane ofapoptotic body.Phosphatidy) Serine is recognised by Phagocyte-ReceptorThrough Antibody / Thrombospondin coating the apoptotic bodyEngulfed by macrophages NecrosisApoptosisPathologicalPhysiological > PathologicalMORPHOLOGYCell SizeCell SwellingCell Shrinkage (AB)ChromatinPyknosisPyknosisKaryorrhesisKaryolysisPlasma membraneDisintegratedIntactNeutrophils+e(Acute inflammation)