LECTURE-6 - LECTURE 6 Apoptosis or Programmed Cell Death...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
LECTURE 6 Apoptosis or Programmed Cell Death Christiaan Leeuwenburgh, Ph.D. Biochemistry of Aging Laboratory, University of Florida, College of Health and Human Performance, Gainesville, FL 32611 What is Apoptosis? Me m b ra ne Bre a kd o wn Chromatin Pat ern Conserved Mito c h o n d ria Changes Mito c h o n d ria structures preserved Nuc le a r Fra g m e nta tio n Intact membranes NORMAL CELL NECROSIS C ELL SWELLING APO PTOSIS C ELL FRAG MENTATION C ELL SHRINKING AND BLEBBING CELLULAR RUPTURING PHAGOCYTOSIS OF APOPTOTIC BODIES Apoptosis: Programmed Cell Death • Definitions: Apoptosis vs. Necrosis – Necrosis derived from Greek “nekrosis,” meaning “deadness.” Necrosis is lethal cell injury or accidental cell death in the living organism. – Apoptosis derived from Greek “apo,” meaning “away from,” and “ptosis,” meaning “to droop” or “to fall.” This is programmed cell death.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
How apoptosis differs from necrosis • Necrotic cell death is a pathological form of cell death resulting from acute cellular injury which is typified by rapid cell swelling and lysis • Apoptosis is controlled autodigestion by activation of endogenous proteases resulting in cell shrinkage, membrane blebbing and nuclear condensation. This results in DNA fragmentation and DNA “ladder” formation How apoptosis differs from necrosis (cont.) • apoptosis results in loss of mitochondrial function unlike necrosis • in apoptosis, the dying cell maintains its plasma membrane integrity • in apoptosis, rapid clearing by phagocytes and formation of apoptotic bodies • no inflammatory response with apoptosis Oxidative Stress Apoptosis • Apoptosis is involved in the morphogenesis of numerous structures – The addition of the antioxidants phenol and dimethyl sulfoxide to developing mouse limbs in culture prevents interdigital cell death and ergo digit individualization. This results in “webbing” between digits (Salas-Vidal et al. 1998) – In untreated limbs, the interdigital space stains for reactive oxygen species, suggesting that oxidative stress-induced apoptosis is necessary for normal embryonic development • Maybe true
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 7

LECTURE-6 - LECTURE 6 Apoptosis or Programmed Cell Death...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online