The document summarizes several metabolic pathways including the hexose monophosphate shunt (HMP shunt), glycogen metabolism, glycogen storage diseases, and gluconeogenesis. The HMP shunt produces pentose and NADPH which are needed for biosynthesis. It is less active in muscles and more active in leukocytes where NADPH is used to produce radicals. Glucose-6-phosphate dehydrogenase deficiency is an X-linked genetic disorder where a defective enzyme causes red blood cell breakdown. Glycogen is the stored form of carbohydrates and is broken down by enzymes into glucose for energy. Glycogen storage diseases occur when enzymes are missing, causing glycogen to build up abnormally. Gl

1. HMP SHUNT
OXIDATIVE PENTOSE PATHWAY

2. The hexose
monophosphate shunt,
also known as the
pentose phosphate
pathway, is a unique
pathway used to create
products essential in the
body for many reasons.
The HMP shunt is an
alternative pathway to
glycolysis and is used to
produce ribose-5-
phosphate and
nicotinamide adenine
dinucleotide phosphate
(NADPH)

4. Significance of HMP shunt:
It generates important products including pentose and NADPH which are
needed for biosynthesis.
In muscles requiring more energy, this pathway is less active it employs
NADP+ instead of NAD+.
In leukocytes this pathway increases during phagocytes where NADPH is
generated by NADPH oxidase that is used to produce superoxide radicals and
destroy phagocytes material.

5. Glucose 6 phosphate dehydrogenase deficiency
Glucose-6-phosphate dehydrogenase deficiency is a genetic disorder that affects red
blood cells, which carry oxygen from the lungs to tissues throughout the body.
 a defect in an enzyme called glucose-6-phosphate dehydrogenase causes red blood
cells to break down prematurely. This destruction of red blood cells is called hemolysis.
• Deficiency of glucose-6-phosphate dehydrogenase
• G6PD deficiency
• G6PDD
• Glucose 6 phosphate dehydrogenase deficiency

6.  glucose-6-phosphate dehydrogenase is inherited in an X-linked pattern. A condition is
considered X-linked if the mutated gene that causes the disorder is located on the X
chromosome, one of the two sex chromosome.
 Males have only one X chromosome and females have two copies of the X
chromosome. A characteristic of X-linked inheritance is that fathers cannot pass X-
linked traits to their sons.

7. symptoms
Anemia. People can have a severe form of anemia called acute hemolytic anemia.
Jaundice. When your skin turns yellow.
Dark-colored pee.
Fatigue.
Being more pale than usual.
Having a rapid heart rate.
Feeling short of breath.
Having an enlarged spleen.

8. Glycogen metabolic pathway
Glycogen is a branched polymer and the storage form of carbohydrates in the
human body. Major sites of storage are the liver and skeletal muscles. Glycogen
is the main source of energy during fasting or in between meals.
 Glycogen provides energy for up to 18 hours, after which energy requirements
are met by fatty acid oxidation.
The 2 metabolic pathways of glycogen are glycogenesis (glycogen synthesis)
and glycogenolysis (glycogen breakdown).
The key regulatory enzymes in these processes are glycogen synthase (in
glycogenesis) and glycogen phosphorylase (in glycogenolysis).
These pathways proceed depending on the energy needs of the cells, generally
modulated by hormonal and allosteric regulators.
Abnormal accumulation of glycogen occurs with enzyme deficiencies causing
different types of glycogen storage disorders.

10. Glycogen storage diseases
• Glycogen storage disease (GSD) is a rare condition that changes the way the body uses
and stores glycogen, a form of sugar or glucose.
• Glycogen is a main source of energy for the body. Glycogen is stored in the liver. When
the body needs more energy, certain proteins called enzymes break down glycogen into
glucose. They send the glucose out into the body.
• When someone has GSD, they are missing one of the enzymes that breaks down
glycogen. When an enzyme is missing, glycogen can build up in the liver. Or glycogen
may not form properly. This can cause problems in the liver or muscles, or other parts of
the body.
• several types of GSD, but the most common types are types I, III, and IV. These types are
also known by other names:

11. • Type I or von Gierke disease. This is the most common form of GSD. People with type I
don’t have the enzyme needed to turn glycogen into glucose in the liver. Glycogen builds
up in the liver. Symptoms often appear in babies around 3 to 4 months old. They may
include low blood sugar (hypoglycemia) and a swollen belly because of an enlarged liver.
• Type III, Cori disease, or Forbes disease. People with type III don’t have enough of an
enzyme called the debranching enzyme, which helps break down glycogen. The glycogen
can’t fully break down. It collects in the liver and in muscle tissues. Symptoms include a
swollen belly, delayed growth, and weak muscles.
• Type IV or Andersen disease. People with type IV form abnormal glycogen. Experts think
the abnormal glycogen triggers the body’s infection-fighting system (immune system).
This creates scarring (cirrhosis) of the liver and other organs such as muscle and the
heart.

12. gluconeogenesis
• Gluconeogenesis is the pathway by which glucose is synthesized from non-carbohydrate metabolites.
• The principal gluconeogenic precursors are pyruvate and lactate, certain gluconeogenic amino acids, and
glycerol, which is derived mainly from fat metabolism.

13. Significance of gluconeogenesis
• During deprivation, the gluconeogenesis cycle is important for blood glucose regulation.
• Many cells and tissues, including RBCs, neurons, skeletal muscle, the medulla of the
kidney, testes, and embryonic tissue, rely on glucose to meet their energy needs.
• The gluconeogenesis cycle removes metabolites such as lactate (produced by muscles
and RBCs) and glycerol from the bloodstream (produced from adipose tissue).