Biochemistry - Significance Of HMP Pathway

1. Rashmi Priyem Saravanan

2. 1. Required for reductive biosynthesis, such
as fatty acid, cholesterol and steroids
2. Free radical scavenging
3. RBC membrane integrity
4. Prevention of formation of met-hemoglobin
5. Detoxification
6. Preserving transparency of lens of eye
7. Bactericidal activity of macrophages
8. Production of ribose and deoxyribose for
DNA and RNA synthesis
Rashmi Priyem Saravanan

3. › i. Liver
› ii. Adipose tissue
› iii. Adrenal cortex
› iv. Mammary glands
› v. Testes and ovaries
› vi. RBCs
› vii. Lens of eye
 A. The Oxidative Phase Of The Pathway Is
› Seen In The Above Organs, Where NADPH Generation Is
Required For Lipid Synthesis Or Steroid Synthesis.
 B. The Non-oxidative Phase Is
› Present In All Tissues, And So Synthesis Of Ribose Is
Possible In All Tissues Of The Body.
Rashmi Priyem Saravanan

4.  The major metabolic role of the pathway is to
provide cytoplasmic NADPH
› For Reductive Biosynthesis Of
 Fatty Acids
 Cholesterol
 Steroids
Rashmi Priyem Saravanan

5.  Free radicals (super oxide, hydrogen peroxide)
are continuously produced in all cells.
 These will destroy DNA, proteins, fatty acids
and all biomolecules, and in turn cells are
destroyed.
 The free radicals are inactivated by enzyme
systems containing
› Superoxide Dismutase (SOD)
› Glutathione Peroxidase (POD)
› Glutathione Reductase (GR)
Rashmi Priyem Saravanan

6.  NADPH is required by the RBC to keep the
glutathione in the reduced state .
 In turn, reduced glutathione will detoxify the
peroxides and free radicals formed within the
RBC .
 NADPH, glutathione and glutathione
reductase together will preserve the
integrity of RBC membrane.
Rashmi Priyem Saravanan

7.  SOD = Super Oxide Dismutase
 POD =Glutathione Peroxidase
 GSH = Glutathione
 GR= Glutathione Reductase
 GPD= Glucose-6-phosphate
Dehydrogenase
Rashmi Priyem Saravanan

8.  NADPH is also required to keep the iron of
hemoglobin in the reduced (ferrous) state
 To prevent the accumulation of met-
hemoglobin
 Met-hemoglobin cannot carry oxygen.
Rashmi Priyem Saravanan

9.  Most of the drugs and other foreign
substances are detoxified by the liver, with
the help of NADPH.
Rashmi Priyem Saravanan

10.  Maximum concentration of NADPH is seen
in lens of eye.
 NADPH is required for preserving the
transparency of lens.
Rashmi Priyem Saravanan

11.  NADPH is required for production of reactive
oxygen species (ROS) (superoxide anion
radical) by macrophages to kill bacteria
 MPO = myeloperoxidase
Rashmi Priyem Saravanan

12.  Ribose and deoxyribose are required for
DNA and RNA synthesis.
 Ribose is also necessary for nucleotide
coenzymes.
Rashmi Priyem Saravanan

13.  ATP is neither utilized nor produced by the
HMP shunt pathway.
 Cells do not use the shunt pathway for
energy production.
Rashmi Priyem Saravanan