Intracellular Accumulation

Question 1

Substances that can be accumulated

Answer 1

•A. Normal endogenous substances which are produced at normal or increased rate, with the metabolic rate inadequate for their removal (e.g., fat accumulation in liver cells)
•B. Abnormal endogenous substances (product of a mutated gene)- may accumulate because of defective folding or transport and inadequate degradation (e.g., α1-antitrypsin disease)

. A normal substance can accumulate due to genetic or acquired defects in its metabolism (e.g., lysosomal storage disease)

•D. Abnormal exogenous substances may accumulate in normal cells because they lack the machinery to degrade such substances (e.g., macrophages laden with environmental carbon).

Question 2

Common intracellular accumulation substances

Answer 2

•Lipids
•Proteins
•Hyaline changes
•Glycogen
•Pigments

Question 3

Steatosis

Answer 3

accumulation of TGs within parenchymal cells either due to excessive entry or defective metabolism and export.
•It can occur in the heart, muscle, kidney and especially the liver causing fatty liver.
•Causes of fatty liver include alcohol abuse, protein malnutrition, DM, obesity, toxins and anoxia.

Question 4

Cholesterol accumulation

Answer 4

Accumulation of cholesterol seen as intracellular cytoplasmic vacuoles can be seen in the following conditions –
•Atherosclerosis
•Xanthomas
•Cholesterolosis
•Niemann-Pick disease, type C

Question 5

Protein accumulation

Answer 5

1. Reabsorption droplets of proteins accumulate in proximal renal tubules in the setting of chronic proteinuria.
   •2.Immunoglobulin in plasma cells, when produced in excessive amounts, producing Russell bodies.