Soy Phospholipid

Lecithinum ex soja, lecithin from soybean, extracted from Glycine max (L.) Merrill [Fam.  Fabaceae], enriched extract with 73 - 79 percent 3-sn-phosphatidylcholine.  

The extract also includes:

• Phosphatidylethanolamine max.  7 percent,
• Phosphatidylinositic acid <0.5 percent,
• Oil 2 - 6 percent,
• Vitamin E 0.2 - 0.5 percent.  

The given range includes both production and analytical variances.  

Pharmacological Properties, Pharmacokinetics, Toxicology

Lecithin extract from soybeans consists on the average of 76 percent phosphatidylcholine and almost entirely of phosphoglycerides, of which the fatty acid linoleic acid predominates.  The quota of phospholipids, which are the chief constituents of cell membrane, are in major part obtained by eating (0.5 - 3 g/day from food) and in lesser degree from synthesis by the liver.  

A deficiency in phospholipids is the inevitable result of chronic parenteric nutrition.  

Under pharmacodynamic characteristics are "hepatoprotective" effects in numerous experimental models, e.g., protection against ethanol, alkyl alcohols, tetrachlorides, paracetamol and galactosamine.  Furthermore, in chronic models (ethanol, thioacetamide, organic solvents), there appears a defense against steatosis and fibrosis of the liver.  The compound works by speeding regeneration and stabilization of membranes, stopping lipid peroxidation and, it is assumed, by collagen synthesis.  

The pharmacokinetics of orally administered lecithin have been examined in animal studies in which the phosphatidylcholine was radioactively marked, the marking on a fatty acid in position 1 or position 2, choline, or a phosphorous.  The respective marker substitutions show the pharmacokinetics.  Phospholipids are degraded to lyso-phosphatidylcholine in the intestine and absorbed primarily in this form.  In the gut wall phospholipids are in part re-synthesized, then circulated through the lymphatic system.  In part the resynthesized phosphatidylcholine is processed in the liver to form fatty acids, choline, and glycerine-3-phosphate.  In plasma, phosphatidylcholine and other phosphoglycerides are tightly bound to lipoproteins and/or albumin.  

Phosphatidylcholine and other phosphoglycerides are degraded chiefly through a series of so-called phospholipases to fatty acids, choline and "glycerin" metabolites to be in turn re-synthesized in the liver and other organs.  The administered metabolites in large part may be integrated within a few hours into body phospholipids.  Their removal corresponds to the excretion of phospholipids and their corresponding metabolites.  

Toxicology

Doses of phosphatidylcholine of up to 10 g/kg body weight in mice and rats and 4.5 g/kg body weight in rabbits given intravenously, intraperitoneally, and orally in a single dose are not toxic.  The "no-effect" dosage over 48 weeks administration to rats lies upward of 3750 mg/kg body weight per day.  Repeated i.v.  application over 12 weeks places the lowest systemic toxic dosage between 0.1 and 1 g/kg body weight and lowest local toxic dosage at over 1 g/kg body weight in rats, and application over 4 weeks to dogs places the lowest toxic dosage at more than 0.1 g/kg body weight in dogs.  

Doses of up to 3750 mg/kg body weight in pregnant animals, animal embryos, and animal neonates showed no pathology of toxicity to reproduction.  The lowest teratogenic or embryo-toxic dosage in rats in oral and intravenous administration was more than 1 g/kg body weight.  In rabbits teratogenic dosages were greater than 1 g/kg body weight for oral administration and greater than 0.5 g/kg body weight in intravenous administration.  Various in vitro tests cannot demonstrate any mutagenic potential.  Carcinogenicity has not been tested.  

Clinical Data

Uses

Less severe forms of hypercholesterolemia in which diet and other non-medical interventions (e.g., exercise program, weight control) have not shown results.  

Improvement of subjective complaints, such as loss of appetite and feeling of pressure in region of liver in toxic/nutritional liver disease and chronic hepatitis.  Prerequisite to the therapy of chronic liver disease is the recognition and avoidance of noxious agents — in the case of alcoholic liver disease, alcohol abstinence.  In chronic hepatitis adjuvant therapy with phospholipids of soybeans is only indicated when improvement of symptoms is discernible from other therapy.  

Contraindications

None known.  

Side Effects

Occasional gastrointestinal effects, i.e., stomach pain, loose stool, and diarrhea.  

None.  

None.  

None known.  

Unless otherwise prescribed:

Daily dosage:

• 1.5 - 2.7 g phospholipids from soybean with 73 - 79 percent 3-sn-phosphatidylcholine in a single dose.  

Not known.  

None.  

None.