25 - hematopoiesis Flashcards
Anemias caused by nutrient deficiencies _ _ _
The Clinical Use of Hematopoietic Growth Factors
Erythropoietin, G-CSF, GM-CSF, and IL-11
iron
vitamin B12
folic acid
Sickle Cell Anemia also
Anemia: Deficiency of _
due to deficiencies of one of three essential nutrients
Red Blood Cells
Iron - most common
B12
Folic acid
is usually defined as a decrease in the amount of red blood cells(RBCs) or hemoglobin in the blood. It can also be defined as a lowered ability of the blood to carry oxygen.
When anemia comes on slowly the symptoms are often vague and may include: feeling tired, weakness, shortness of breath or a poor ability to exercise. Anemia that comes on quickly often has greater symptoms which may include: confusion,feeling like one is going to passout,andincreasedthirst.
Anemia
Anemia must be significant before a person becomes noticeably pale
4- 5 grams of _in your body 65% of it is in hemoglobin 15-30% stored in hepatocytes and within the reticuloendothelial system (phagocytes, mainly macrophages) _ is the major storage protein
iron
Ferritin - main storage protein of iron
Iron absorbed in _
Combines with in plasma with a protein transferrin
Excess Iron principally deposited in _ (more) and reticuloendothelial cells (phagocytes, egmacrophages; less) of the blood marrow and stored within ferritin
If iron in plasma falls low, some iron from the ferritin storage pool is removed and transported (via transferrin) to where it is needed
small intestine
liver hepatocytes - more
Iron is absorbed, either as free _ ion, or as
free ferrous (Fe++)
hemeiron.
_ is transported in the plasma bound to transferrin.
Iron
Fe3+ carried on transferrin
Heme biosynthesis:
Mainly in the liver and bone marrow. Pathway involves mitochondrial and cytoplasmic enzymes.
Last step involves incorporation of _
Fe++
Iron is called a one way element. Very little (0.5 –1.0 mg/ day) is _ through excretion each day
lost
regulation of homoeostasis is done at the absorption level
bleeding wil cause loss of iron from the body
folic acid and B12 are necessary for _ synthesis. Hematopoiesis is especially sensitive (very rapid turnover rate)
necessary for DNA synthesis
200 Billion per day
Cancer chemotherapy - aimed at suppressing rapidily dividing cells
_ are rapid dividing cells not intentionally killed
RBC
_ are usually the first people to notice anemia patients
dentists
pale lining gums and loss of texture on tongue (smoothening of tongue)
what does ferritin do
binds of iron and stores it
_ iron to get into blood
once in blood binds to transferrin
Fe+++ to get into blood
Fe++ (free ferrous or heme iron) absorbed
Heme
Made in _ and _
Involved mitochondrial and cytoplasmic enzymes
Last step have to convert it to or incorporate _
liver and bone marrow
last step - Fe++ - 2 ferrous
Ferric - Fe 3 -
can now get into blood
Ferrous - Fe 2 -
absorbed
many _proteins
- Tend be involved in gas molecules or moving electrons around
Iron 2 to iron 3 and back and forth
HEME
Iron levels are controlled at the level of _
absorption
IRON is a one way elevemt - gets in and stays there
Doesn’t excrete thru urine
TX for iron deficiency anemia
oral or parenteral iron supplement
_ and _ deficiency need more DNA metabolism
Folic acid (DNA synthesis, growing cells need this)
and B12 (important in myelination process) anemias
_ anemia - reflects an absorption problem
Need protein INTRINSIC FACTOR to absorb
B12 (Cobalamine)
intrinsic factor - gylcoprotein
combine with B12 forming complex that resist digestion by GIT enzymes in stomach
deicicency of _ causes
macrocytic anemia due to failure of maturation of RBC
and neurological manifestations because it is needed for myelination of nerves
vitamin B12
why doesn’t oral admin of B12 for B12 anemia patients work
B12 anemia - lacking intrsnic factor = leads to production of GASTRIC ACID
Doesn’t really do anything taken orally because missing intrnsic factor - need to be injected
because prob due to missing of intrisinc factor - so doesn’t form that complex
need parenteral
macrocytic anemia
megaloblastic anemias - presence of large RBC’s
caused by?
defective DNA syntheisis
Cobalamin (B12 deficiency) - pernicisous anemia = most comon cause
and folic acid deficinecy - poor nutrition - anorexia, malabsorb, ETOH, hemodialysis
how is sickle-cell disease considered an anemia
Hemolysis of RBC’sis the actual cause of the illness
Sickled cells only last 10-20 days
how to tx sickle cell anemia
bone marrow(stem cell) transplant
need donor - 85 success = risky
only done in severe cases
_ a glycoprotein that is produced in the kidney controls erythropoiesis - stimulates RBC proliferation
Given to cancer chemotherapy patients
Erythropoietin
senses
and responds to low oxygen or hypoxia
G-CSF, GM-CSF are used to tx chemotherapy induced _
neutropenia - low PMN count
G-CSF glycoprotein that stims marrow to produce granuloytes and stem cells and release them
GM-CSF - monomeric glycoprotein secreted by macrophages, T cells, Mast cells endothelial cells and fibroblasts that fxn as cytokin e
IL-_ has been demonstrated to improve platelet recovery after chemoinduced thrombocytopenia (loss of platelets)
IL-11
