18:3 (n-6)

18:3 (n-6) Uses, Dosage, Side Effects, Food Interaction and all others data.

18:3 (n-6), or gamma-linolenic acid (γ-Linolenic acid) or GLA, is an essential fatty acid (EFA) comprised of 18 carbon atoms with three double bonds that is most commonly found in human milk and other botanical sources . It is an omega-6 polyunsaturated fatty acid (PUFA) also referred to as 18:3n-6; 6,9,12-octadecatrienoic acid; and cis-6, cis-9, cis-12- octadecatrienoic acid . 18:3 (n-6) is produced minimally in the body as the delta 6-desaturase metabolite of Linolenic acid. It is converted to Dihomo-gamma-linolenic acid, a biosynthetic precursor of monoenoic prostaglandins such as PGE1. While 18:3 (n-6) is found naturally in the fatty acid fractions of some plant seed oils , Evening primrose oil and Borage oil are rich sources of gamolenic acid. Evening primrose oil has been investigated for clinical use in menopausal syndrome, diabetic neuropathy, and breast pain, where gamolenic acid is present at concentrations of 7-14% . 18:3 (n-6) may be found in over-the-counter dietary supplements. 18:3 (n-6) is also found in some fungal sources and also present naturally in the form of triglycerides . Various clinical indications of gamolenic acid have been studied, including rheumatoid arthritis, atopic eczema, acute respiratory distress syndrome, asthma, premenstrual syndrome, cardiovascular disease, ulcerative colitis, ADHD, cancer, osteoporosis, diabetic neuropathy, and insomnia.

18:3 (n-6) is converted to PGE1, which exhibits anti-inflammatory, antithrombotic, antiproliferative, and lipid-lowering effects . PGE1 also induces smooth muscle relaxation and vasodilation. 18:3 (n-6) is an essential component of membrane phospholipids, including the mitochondrial membrane, where it enhances the the integrity and the fluidity of the membrane .

Bone and joint health: In a pilot study of women with a mean age of 79.5 years and senile osteoporosis, the use of gamolenic acid in combination with calcium and eicosapentaenoic acid was associated with an increase in femoral bone density and lumbar spine density in comparison to placebo, where there were no observable changes . In clinical studies of patients with rheumatoid arthritis, treatment with gamolenic acid-containing oils resulted in an improvement in symptoms, measured by joint tenderness counts and scores, joint swelling scores, physician global assessment, and pain .

18:3 (n-6)
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
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Trade Name	18:3 (n-6)
Generic	Gamolenic acid
Gamolenic acid Other Names	18:3 (n-6), gamma-Linolenic acid, gamoleic acid, Gamolenic acid, Octadeca-6,9,12-triensäure, γ-Linolensäure
Type
Formula	C₁₈H₃₀O₂
Weight	Average: 278.4296 Monoisotopic: 278.224580204
Protein binding	No pharmacokinetic data available.
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country
Last Updated:	September 19, 2023 at 7:00 am

Uses

18:3 (n-6) is an ingredient found in a variety of nutritional products.

Indicated as a dietary supplement for over-the-counter uses.

How 18:3 (n-6) works

Once gamolenic acid (GLA) is absorbed and converted to dihomo-gamolenic acid (DGLA), circulating DGLA fatty acids are converted to several lipid mediators with predominantly anti-inflammatory properties, such as prostaglandin-E1 (PGE1) and 15-HETrE. The anti-inflammatory effects of DGLA are attributed to both the anti-inflammatory properties of DGLA-derived metabolites and the ability of DGLA and its products to compete with arachidonic acid (AA) in the synthesis of pro-inflammatory potent eicosanoid products, such as prostaglandins, thromboxane and leukotrienes . Both PGE1 and 15-HETrE are known to suppress inflammation, promote vasodilation, lower blood pressure, inhibit smooth muscle cell proliferation, inhibit platelet aggregation, and exert anti-neoplastic activities . PGE1 is a potent vasodilator that binds to surface receptors on smooth muscle cells, increasing intracellular cAMP . PGE1 is binds to G protein coupled surface PGE (EP) receptors and prostacyclin (IP) receptors as a natural ligand .

GLA is proposed to enhance calcium absorption, reduce excretion and increase calcium deposition in bone . It is proposed that GLA may suppress tumor growth in vivo by increasing the expression of E-cadherin, a cell-to-cell adhesion molecule that acts as a suppressor of metastasis. Another possible mechanism of tumour suppression is that GLA also reduces tumor-endothelium adhesion, which is a key factor in the establishment of distant metastases, partly by improving gap junction communication within the endothelium . By targeting the inflammatory process involved in the pathogenesis of diabetic nephropathy, GLA inhibits the expression of inflammatory mediators that tend be elevated in diabetes, intracellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1), thereby attenuates the recruitment and infiltration of monocytes or macrophages .

Toxicity

Oral TDLO reported in man is 3.14 mg/kg/42D (intermittent) . While limited cases of soft stool, belching, and abdominal bloating have been reported from dietary supplements containing gamolenic acid, daily doses up to 2.8 g were well tolerated .

Food Interaction

No interactions found.

Volume of Distribution

No pharmacokinetic data available.

Elimination Route

The findings from a pharmacokinetic study suggest that therapeutic levels of GLA can be achieved within a week. The fasting plasma GLA levels plateaued within seven days of beginning treatment, regardless of dose .