Failure of our body’s metabolic processes which leads to a large or very less amount of essential substances in the body is called a metabolic disorder. That being said, we can understand that the failure in lipid metabolism causes Lipid Metabolism disorders, also known as DYSLIPIDEMIA.

COMMON SYMPTOMS OF DYSLIPIDEMIA

  • Leg pain 
  • Chest pain
  • Indigestion 
  • Sleep problems
  • Dizziness 
  • Heart palpitations
  • Vomiting and nausea
  • Swelling 

CLASSIFICATION OF LIPID METABOLISM DISORDERS:

Lipid metabolism disorders are widely classified into two categories based on their causes. They are,

  • PRIMARY LIPID DISORDERS.
  • SECONDARY LIPID DISORDERS.

With this as the outline, let us see about each type of lipid metabolism in detail.

PRIMARY DYSLIPIDEMIA

Primary lipid diseases often stand alone and are not a side effect of an underlying disease. They are often genetic ( either hereditary or due to mutation).

Example: Familial hyperlipidaemia, Abetalipoproteinaemia.

Familial hyperlipidaemia

This lipid disorder doesn’t depend on environmental factors. It is characterized by high plasma cholesterol levels from early childhood. This disorder takes place in the following sequence:

Defect in LDL(LOW-DENSITY LIPOPROTEINS) receptor leads to reduced uptake of lipids by the liver which in turn leads to increased cholesterol concentration in the plasma. This disorder often results in an increased risk of ischemic heart disease.

DYSLIPIDEMIA

Causes

FH can be due to inherited changes or mutations in the low-density lipoproteins receptor genes(LDLR), Apolipoprotein B (ApoB) gene, and proprotein convertase subtilisin/kexin Type 9 (PCSK9) gene which control the regulation of cholesterol in our blood. Major cases with FH are found to have mutation in one of these three genes.

Symptoms

Though we have seen general symptoms of lipid metabolism disorder each disorder has its own set of symptoms. The symptoms of Familial Hypercholesterolemia include;

  • Bumps or lumps around our knees and other joints.
  • Swelling and pain in the Achilles tendon ( tendon in the calves)
  • Yellowing around the eyes
  • Whitish grey spot outside our cornea

Abetalipoproteinemia

It is a rare genetic disorder causing hindrance in fat transport in newborns. Deficiency of vitamins A, E and K (fat soluble vitamins) can lead to this disorder along with neurological deterioration. If ignored this may lead to deterioration of spinocerebellar and dorsal column tracts and may also cause Ataxia( loss of muscle control), peripheral neuropathy ( damage to nerves outside brain and spinal cord) and retinal degeneration.

Causes

This disorder is said to be caused due to mutations in the MTTP ( Microsomal Triglyceride Transfer Protein) gene. MTTP is associated with production of beta lipoproteins ( help in lipid transport to the bloodstream) in the liver and intestine. With the decrease in the transport protein the regulation of lipids also gets disrupted leading to Abetalipoproteinemia.

Symptoms

  • No weight gain and growth
  • Diarrhoea
  • Steatorrhea (fatty foul smelling stool)
  • Reduced HDL ( high density lipoproteins)
  • Neurological complications
  • Inability to control voluntary movements

SECONDARY DYSLIPIDEMIA

Secondary disorders are often seen as a side effect of another disease. It may also be due to unhealthy lifestyle choices. Example : Hypercholesterolemia due to diabetes, hypothyroidism etc.,

Causes

Diabetes Mellitus ( Insulin affects liver apoprotein production, insulin action on adipose and muscle is reduced)

  • Hyperthyroidism and hypothyroidism ( thyroxine controls cholesterol and lipid levels in our body and also helps liver in the production of fatty acids)
  • Nephrotic syndromes 
  • Alcohol and drug consumption.

Other than the above-mentioned causes it may also be caused due to obesity, drug intake, pregnancy, and diet.

Bonne Lecture 🙂

Click here to read about Sleep and Dream. (add link after lipid blog is published)

Click here to read about Stocks.