trace elements

• Condition leading to deficiency

  1. Decreased Intake

  2. Impaired Absorption

  3. Increased Excretion

  4. Genetic Abnormalities
• Trace elements


  • Elements found in the body in low-concentration circulating in the body
  • Have specific in vivo metabolic functions and other similar elements cannot effectively do it
  • Consists of metals except for selenium, halogens, fluoride, and iodine
• Essential Trace Elements


  • Iron
• Iron


  • Common metallic element
  • Reduced form is the biologic form
  • Responsible for converting ferric to ferrous
• Responsible for converting ferric to ferrous

  Ferric Reductase - an enzyme responsible for converting ferric form to ferrous form of iron in the intestinal epithelium
• Iron is a Prooxidant, contributing to lipid peroxidation, atherosclerosis, DNA damage, and neurodegenerative diseases
• Iron is a Prooxidant

  Contributes to lipid peroxidation, atherosclerosis, DNA damage, and neurodegenerative diseases
• Non-Essential Trace Elements


  • It does not contribute to biochemical or functional process
  • Medically significant due to toxicity
• Trace elements


  • Iron, Copper, and Zinc
• Ultratrace elements


  • Selenium, Chromium, and Manganese
• Two classifications of trace elements

  • According to Contribution/ Function to Biochemical Process
  • According to Concentration in Plasma/ Serum
• Enzyme responsible for converting ferric form to ferrous form of iron in the intestinal epithelium


  ferric reductase
• We need Anti-oxidants instead of prooxidants in the free form
• Iron in the plasma/serum can be a prooxidant
• Iron is mainly present in the red blood cell
• Amount of Iron in different locations

  • 2-2.5g in HEMOGLOBIN
  • 3-5mg in PLASMA (FREE & BOUND TYPE)
  • 130mg in MYOGLOBIN
  • 8mg in TISSUE
• Iron is stored in the Liver, Spleen, and Bone Marrow as Ferritin and Hemosiderin
• Apoferritin


  • Binds to the ferrous form of iron in the intestinal mucosa
• Ferritin


  • Stores the ferrous form of iron
• A low ferritin level is used as a diagnostic tool for determining individuals with iron deficiency
• Apotransferrin


  • Binds the ferric form of iron for transport throughout the body
• Transferrin


  • Transporter for the ferric form of iron
• Ferroportin


  Regulates/promotes the exportation of iron from cells
• Hepcidin


  Regulates iron absorption in the upper GIT by modulating the activity of ferroportin
• Serum iron levels are falsely elevated by hemolysis and affected by diurnal variation
• Diurnal Variation: Iron levels are highest in the morning and lowest at night
• Nocturnal Variation: Iron levels are high in the evening and low in the morning
• Conditions with Increased Iron Levels

  • Iron Poisoning (Overdose)
  • Hemochromatosis
  • Viral Hepatitis
• Non-Iron Deficiency Anemias


  • Thalassemia
  • Aplastic anemia
  • Megaloblastic anemia
  • Sideroblastic anemia
  • Hemolytic anemia
  • Pernicious anemia
• Conditions with Decreased Iron Levels

  • Iron Deficiency Anemia (IDA)
• When insulin supply is low


  Can cause diabetes mellitus
• Non-Iron Deficiency Anemias


  • Thalassemia
  • Aplastic anemia
  • Megaloblastic anemia
  • Sideroblastic anemia
  • Hemolytic anemia
  • Pernicious anemia
• Iron Deficiency Anemia (IDA)


  • Most common anemia; especially among children/pediatrics
  • Common in impoverished communities
• DECREASE LEVEL OF IRON

  • IDA
  • Malnutrition - low intake of iron-rich food or no iron supplement
  • Malignancy (e.g. cancer, malignant conditions)
  • Chronic Infection
  • Nephrotic Syndrome
• Most trace elements, including iron, are derived from the diet. A low iron level in the diet results in a decrease in iron level
• Total Iron Binding Capacity

  The amount of iron that could be bound by saturating transferrin and other minor-iron binding proteins present in the serum or plasma sample
• In patients with Iron Deficiency Anemia (IDA), they have high Total Iron Binding Capacity (TIBC) because they have no/low iron in the plasma or serum, resulting in no binding of iron in the transferrin (no saturated transferrin)
• In patients with Non-IDA such as hemolytic, megaloblastic, sideroblastic types of anemia, they have low Total Iron Binding Capacity (TIBC) because they have high iron levels; more transferrin will be saturated
• Increased Total Iron Binding Capacity (TIBC)


  Occurs in IDA, hepatitis, iron-supplemented pregnancy
• Decreased Total Iron Binding Capacity (TIBC)

  Occurs in Non-IDA and nephrosis