A SHORT REVIEW ABOUT INTRACELLULAR ACCUMULATIONS ALTHOUGH ITS A VAST TOPIC

2. • Accumulation of abnormal amounts of various
substances due to manifestations of metabolic
derangements of the cell

3. INTRACELLULAR
ACCUMULATIONS
NORMAL CELLULAR
COMPONENTS
lipid, carbohydrates
ABNORMAL SUBSTANCES
Endogenous and
Exogenous

4. SITES
• Cytoplasm (phagolysosomes)
• Nucleus

5. MECHANISM OF ACCUMULATIONS
• Due to overproduction
• Due to inadequate metabolism
• Lack of enzyme machinery to remove

6. Normal substance produced at normal or increase rate
Metabolism is inadequate to remove it
Fatty change in liver
Accumulation

7. Mutated gene
Abnormal protein folding
Inability to degrade abnormal protein
Accumulation
Alpha 1 antitrypsin
def.

8. Normal endogenous substance
Enzyme
Deficiency
Metabolite
Accumulation
Storage
disorders

9. Exogenous substance
No enzymatic machinery for its degradation or transport
Accumulation
Accumulation of
carbon in lungs

10. ACCUMULATION OF LIPIDS

11. Normal lipid metabolism
Free fatty acids from adipose tissue or ingested food
Transported to hepatocytes
Esterified
Triglycerides
Converted to
Cholesterol or phospholipids
Oxidized to
Ketone bodies

12. STEATOSIS OR FATTY CHANGE
• Abnormal accumulation of triglycerides in liver
parenchyma

13. Alcohol
Mitochondria
Toxin and Malnutrition
Apoproteins
Hypoxia
Starvation
Inhibit oxidation
Mobilization
Accumulation of lipids
Fatty change or steatosis

14. FATTY CHANGE - LIVER
Grossly
• Liver enlarges, become increasingly yellow, soft and greasy.
Microscopically
• Small vacuoles in cytoplasm around the nucleus
• Vacuoles coalesce displacing the nucleus to periphery
• Occasionally fatty cysts are formed

19. FATTY CHANGE - HEART
• Occurs due to prolonged moderate hypoxia as in
anemia
• In case of infectious myocarditis like of diphtheria.

20. Grossly
• Bands of yellow myocardium alternating with bands of
darker red brown uninvolved myocardium
• Tigered effect
Microscopically
• Intracellular deposits of fat

21. CHOLESTEROL AND CHOLESTEROL ESTERS
• Atheromatous plaque

22. • Cholesterolosis

23. Xanthomas

24. PROTEIN
Intracellular accumulation of protein usually appear as
• Round eosinophilic droplets,
• Vacuoles or
• Aggregates
in cytoplasm

29. GLYCOGEN
• It’s a readily available energy source in cytoplasm of
cells
• Excessive intracellular accumulation occurs in
abnormal glucose or glycogen metabolism
• DM (renal tubular epithelial cells, liver, beta cells,
heart muscles)
• Glycogen storage disorders

33. Angiokeratoma corporis diffusum
(Fabry's disease)

34. EWINGS SARCOMA

35. PIGMENT
• Exogenous
• Endogenous

36. Exogenous
•
•
•
•
•
Most common is carbon (coal dust).
Common air pollutant.
Inhaled by macrophages within alveoli
Leads to Anthracosis (blackening of lungs)
Severe accumulation like in coal miners leads to coal
worker’s pneumoconiosis

38. Pneumoconiosis
• Silicosis – Silica dust, stone and sandblasters
• Asbestosis – Asbestos dust in shipbuilding workers
• Byssinosis – Cotton dust

40. Endogenous
Lipofuscin
• Lipochrome or wear and tear pigment
• Derived through lipid peroxidation of polyunsaturated lipids of
membranes
• Telltale sign of lipid peroxidation and free radical injury
• In sections appears as yellow brown, finely granular, cytoplasmic,
often perinuclear pigment

41. • Seen in cells undergoing slow regressive changes as in liver and heart
of aging patients or patient with severe malnutrition or cachexia.

42. Other pigments
Melanin
Hemosiderin
Bilirubin