LIPID METABOLIC DISORDERS
Md. Abdur Rakib, PhD Associate Professor
Dept . of Biochemistry and Molecular Biology University of Rajshahi
Sudden Infant Death Syndrome (SIDS) Sudden Infant Death Syndrome (SIDS)
SIDS?
Sudden Infant Death Syndrome (SIDS) is the sudden death of an infant under 1 year of age
Most likely to occurs in infants between two and four month olds; 91% occur between 1 and 6 months of age It does not have any symptoms and can occur
unexpectedly
SIDS-a disorder due to blockade in β-oxidation SIDS-a disorder due to blockade in β-oxidation
The sudden infant death syndrome (SIDS) is an unexpected death of healthy infants, usually overnight. The real cause of SIDS is not known.
It is now estimated that at least 10% of SIDS is due to deficiency of medium chain acyl-CoA dehydrogenase (MCAD). The enzyme defect has a frequency of 1 in 10,000 births and is, in fact, more prevalent than phenylketonuria. The occurrence of SIDS is
explained as follows
Glucose is the principal source of energy, soon after eating or feeding babies. After a few hours, the glucose level and its utilization decrease and the rate of fatty acid oxidation must simultaneously increase to meet the energy needs. The sudden death in infants is due to a blockade in β-oxidation caused by a deficiency in MCAD.
Sudden Infant Death Syndrome (SIDS) Sudden Infant Death Syndrome (SIDS)
Refsum’s disease Refsum’s disease
Refsum’s disease is a rare but severe neurological disorder characterized by cerebral ataxia and peripheral neuropathy.
The patients of this disease accumulate large quantities of an unusual fafty acid, phytanic acid. lt is derived from phytol, a constituent of chlorophyll. Hence it is found mostly in plant foods. However, it is also present in milk lipids and animal fats.
Phytanic acid cannot undergo B-oxidation due to the presence of a methyl group on carbon-3. This fatty acid undergoes initial α-
oxidation (to remove α-carbon as carbon dioxide) and this is followed by β-oxidation
Refsum's disease is caused by a defect in the α -oxidation due to the deficiency of the enzyme phytanic acid α-
oxidase. The result is that phytanic acid cannot be converted to a
compound that can be degraded by β-oxidation.
The patients should not consume diets containing chlorophyll (i.e., green leafy vegetables)
Refsum’s disease
Refsum’s disease
Myocardial infarction Myocardial infarction
Myocardial infarction (MI) or acute myocardial infarction (AMI), commonly known as a heart
attack, is the interruption of blood supply to part of the heart, causing some heart cells to die.
Myocardial infarction is an ischemic necrosis of the myocardium, caused by occlusion of
coronary artery and prolonged myocardial
ischemia.
Atherosclerotic plaques typically consist of a lipid-rich core, which is found in the central portion of the eccentrically
thickened intima. The lipid core is bounded on the luminal surface by a fibrous cap. The integrity of the fibrous cap
determines the stability of the plaque. The vulnerable plaque typically has a substantial lipid core and a thin, friable fibrous cap. Shear stress is increased at sites of plaques prone to
rupture. When there is plaque rupture, the antigen HLA-DR is expressed by smooth muscle cells (SMCs) and leukocytes. The expression of HLA-DR is felt to be a marker for activation of SMCs. In contrast, the stable atherosclerotic plaque typically has a relatively thick fibrous cap, which is more resistant to
shear stress and less prone to rupture.
Myocardial infarction
Myocardial infarction
Carnitine palmitoyltransferase (CPT) deficiencies Carnitine palmitoyltransferase (CPT) deficiencies
Carnitine palmitoyltransferase II deficiency is an inherited
genetic metabolic disorder characterized by an enzymatic defect that prevents long-chain fatty acids from being transported into
the mitochondria for utilization as an energy source.
Carnitine palmitoyltransferase (CPT) deficiencies Carnitine palmitoyltransferase (CPT) deficiencies
The CPT system is made up of two separate proteins
located in the outer (CPT1) and inner (CPT2) mitochondrial membranes.
Carnitine Palmitoyl Transferase Deficiency (also known as CPT-II) is an inherited fatty acid oxidation disorder.
Once the body uses up its primary source of energy
(glucose, or blood sugar), the body begins to fail because it cannot then make energy from fats. Therefore, people with CPT-II deficiency must eat on a very regular basis and should not go long without food.
It is a state of acute, diffuse alveolar damage characterized by increased capillary permeability, pulmonary edema and
refractory hypoxemia.
The hallmarks of ARDS is
- diffuse injury to cells which form the alveolar barrier - surfactant dysfunction
- activation of the innate immune response, and -abnormal coagulation.
In effect, ARDS results in impaired gas exchange within the lungs at the level of the microscopic alveoli.
