Lipopolysaccharides

Also known as:  Endotoxins;  LPS

Lipopolysaccharides are a group of Glycolipids that are composed of Polysaccharides bound to a Lipid.

Lipopolysaccharides are generally toxic but are utilized therapeutically as a means of evoking a response from the Immune System.  In this role, Lipopolysaccharides are the active agents in Coley’s Toxins (otherwise known as Mixed Bacterial Vaccine).

Microorganisms

 Lipopolysaccharides occur in the Cell Walls of all Gram-Negative Bacteria (the presence of Lipopolysaccharides accounts for some of the ability of Gram-Negative Bacteria to cause illness (i.e. Lipopolysaccharides function as Antigens)):

 When Detrimental Bacteria are broken down (metabolized) within the body, Lipopolysaccharides are released.

 Lipopolysaccharides are only present in the outer Membranes of Gram-Negative Bacteria.  They are only released when the Bacteria is disrupted or killed.  Lipopolysaccharides released by Bacteria are less toxic than Exotoxins which are secreted by Bacteria while they are still alive or not disrupted.

The toxic effects of Lipopolysaccharides are known as Endotoxemia or Sepsis.

Digestive System

 Lipopolysaccharides may cause Cholestasis (blockage of the Bile Duct).  ^[1]

Immune System

 The Immune System treats Lipopolysaccharides as Antigens.

 Lipopolysaccharides may cause Inflammation.

Metabolism

 Lipopolysaccharides may cause the Oxidation (Peroxidation) of Lipids (i.e. Lipid Peroxidation) in the Liver and Spleen.

 Lipopolysaccharides may damage the Liver:

 Lipopolysaccharides may stimulate the production of Free Radicals (as a result of Lipid Peroxidation) in the Liver.

Nervous System

 Lipopolysaccharides may cause impairment of Rapid Eye Movement Sleep (REM Sleep).  ^[2]