17-12-2014, 11:47 PM
Add Gamma Linolenic Acid to the list of "5 alpha reductase inhibitors"
GLA (also found in evening primrose oil, borage seed oil, black currant oil)
Reductase by specific aliphatic unsaturated fatty acids.
Abstract
Human or rat microsomal 5 alpha-reductase activity, as measured by enzymic conversion of testosterone into 5 alpha-dihydrotestosterone or by binding of a competitive inhibitor, [3H]17 beta-NN-diethulcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one ([3H]4-MA) to the reductase, is inhibited by low concentrations (less than 10 microM) of certain polyunsaturated fatty acids. The relative inhibitory potencies of unsaturated fatty acids are, in decreasing order: gamma-linolenic acid greater than cis-4,7,10,13,16,19-docosahexaenoic acid = cis-6,9,12,15-octatetraenoic acid = arachidonic acid = alpha-linolenic acid greater than linoleic acid greater than palmitoleic acid greater than oleic acid greater than myristoleic acid. Other unsaturated fatty acids such as undecylenic acid, erucic acid and nervonic acid, are inactive. The methyl esters and alcohol analogues of these compounds, glycerols, phospholipids, saturated fatty acids, retinoids and carotenes were inactive even at 0.2 mM. The results of the binding assay and the enzymic assay correlated well except for elaidic acid and linolelaidic acid, the trans isomers of oleic acid and linoleic acid respectively, which were much less active than their cis isomers in the binding assay but were as potent in the enzymic assay. gamma-Linolenic acid had no effect on the activities of two other rat liver microsomal enzymes: NADH:menadione reductase and glucuronosyl transferase. gamma-Linolenic acid, the most potent inhibitor tested, decreased the Vmax. and increased Km values of substrates, NADPH and testosterone, and promoted dissociation of [3H]4-MA from the microsomal reductase. gamma-Linolenic acid, but not the corresponding saturated fatty acid (stearic acid), inhibited the 5 alpha-reductase activity, but not the 17 beta-dehydrogenase activity, of human prostate cancer cells in culture. These results suggest that unsaturated fatty acids may play an important role in regulating androgen action in target cells.
http://www.ncbi.nlm.nih.gov/pubmed/1637346
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Gamma Linolenic Acid
Scientific/medical name(s): gamma linolenic acid
Description
Gamma linolenic acid (GLA) is an omega-6 unsaturated fatty acid made in the human body from linoleic acid, an essential fatty acid found in vegetable oils and egg yolks. The main supplemental sources of GLA are oils of the seeds of evening primrose, borage, and black currant plants. (For more information, see Evening Primrose.) Many companies sell these oils as good sources of GLA. It is also found in human breast milk.
Overview
Some studies have shown that GLA can slow or stop the growth of some types of cancer cells in tissue cultures in the laboratory. The same kinds of studies suggest that GLA may help some cancer drugs to work better. However, there is very little evidence as yet that GLA supplements work to prevent or treat cancer in humans. Human studies are under way to evaluate the role of GLA and other essential fatty acids on the growth of cancer.
How is it promoted for use?
Gamma linolenic acid is normally used by the body to make prostaglandins (hormone-like substances). Prostaglandins are believed to be involved in many processes in the body, including regulation of the immune system.
http://www.cancer.org/treatment/treatmen...lenic-acid
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Dosing
GAMMA LINOLENIC ACID SIDE EFFECTS & SAFETY
Gamma linolenic acid is POSSIBLY SAFE for most adults when taken by mouth in amounts of no more than 2.8 grams per day for up to a year. It can cause digestive-tract side effects, such as soft stools, diarrhea, belching, and intestinal gas. It can also make blood take longer to clot.
Special Precautions & Warnings:
Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking gamma linolenic acid if you are pregnant or breast-feeding . Stay on the safe side and avoid use.
Bleeding disorders: Gamma linolenic acid might slow blood clotting. There is some concern that it might increase the risk of bruising and bleeding in people with bleeding disorders.
Surgery: Since gamma linolenic acid might slow blood clotting, there is concern that it might increase the risk of extra bleeding during and after surgery. Stop taking gamma linolenic acid at least 2 weeks before a scheduled surgery.
http://www.webmd.com/vitamins-supplements/ingredientmono-805-GAMMA%20LINOLENIC%20ACID.aspx?activeIngredientId=805&activeIngredientName=GAMMA%20LINOLENIC%20ACID
GLA (also found in evening primrose oil, borage seed oil, black currant oil)
Reductase by specific aliphatic unsaturated fatty acids.
Abstract
Human or rat microsomal 5 alpha-reductase activity, as measured by enzymic conversion of testosterone into 5 alpha-dihydrotestosterone or by binding of a competitive inhibitor, [3H]17 beta-NN-diethulcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one ([3H]4-MA) to the reductase, is inhibited by low concentrations (less than 10 microM) of certain polyunsaturated fatty acids. The relative inhibitory potencies of unsaturated fatty acids are, in decreasing order: gamma-linolenic acid greater than cis-4,7,10,13,16,19-docosahexaenoic acid = cis-6,9,12,15-octatetraenoic acid = arachidonic acid = alpha-linolenic acid greater than linoleic acid greater than palmitoleic acid greater than oleic acid greater than myristoleic acid. Other unsaturated fatty acids such as undecylenic acid, erucic acid and nervonic acid, are inactive. The methyl esters and alcohol analogues of these compounds, glycerols, phospholipids, saturated fatty acids, retinoids and carotenes were inactive even at 0.2 mM. The results of the binding assay and the enzymic assay correlated well except for elaidic acid and linolelaidic acid, the trans isomers of oleic acid and linoleic acid respectively, which were much less active than their cis isomers in the binding assay but were as potent in the enzymic assay. gamma-Linolenic acid had no effect on the activities of two other rat liver microsomal enzymes: NADH:menadione reductase and glucuronosyl transferase. gamma-Linolenic acid, the most potent inhibitor tested, decreased the Vmax. and increased Km values of substrates, NADPH and testosterone, and promoted dissociation of [3H]4-MA from the microsomal reductase. gamma-Linolenic acid, but not the corresponding saturated fatty acid (stearic acid), inhibited the 5 alpha-reductase activity, but not the 17 beta-dehydrogenase activity, of human prostate cancer cells in culture. These results suggest that unsaturated fatty acids may play an important role in regulating androgen action in target cells.
http://www.ncbi.nlm.nih.gov/pubmed/1637346
________________________________
Gamma Linolenic Acid
Scientific/medical name(s): gamma linolenic acid
Description
Gamma linolenic acid (GLA) is an omega-6 unsaturated fatty acid made in the human body from linoleic acid, an essential fatty acid found in vegetable oils and egg yolks. The main supplemental sources of GLA are oils of the seeds of evening primrose, borage, and black currant plants. (For more information, see Evening Primrose.) Many companies sell these oils as good sources of GLA. It is also found in human breast milk.
Overview
Some studies have shown that GLA can slow or stop the growth of some types of cancer cells in tissue cultures in the laboratory. The same kinds of studies suggest that GLA may help some cancer drugs to work better. However, there is very little evidence as yet that GLA supplements work to prevent or treat cancer in humans. Human studies are under way to evaluate the role of GLA and other essential fatty acids on the growth of cancer.
How is it promoted for use?
Gamma linolenic acid is normally used by the body to make prostaglandins (hormone-like substances). Prostaglandins are believed to be involved in many processes in the body, including regulation of the immune system.
http://www.cancer.org/treatment/treatmen...lenic-acid
___________________________
Dosing
GAMMA LINOLENIC ACID SIDE EFFECTS & SAFETY
Gamma linolenic acid is POSSIBLY SAFE for most adults when taken by mouth in amounts of no more than 2.8 grams per day for up to a year. It can cause digestive-tract side effects, such as soft stools, diarrhea, belching, and intestinal gas. It can also make blood take longer to clot.
Special Precautions & Warnings:
Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking gamma linolenic acid if you are pregnant or breast-feeding . Stay on the safe side and avoid use.
Bleeding disorders: Gamma linolenic acid might slow blood clotting. There is some concern that it might increase the risk of bruising and bleeding in people with bleeding disorders.
Surgery: Since gamma linolenic acid might slow blood clotting, there is concern that it might increase the risk of extra bleeding during and after surgery. Stop taking gamma linolenic acid at least 2 weeks before a scheduled surgery.
http://www.webmd.com/vitamins-supplements/ingredientmono-805-GAMMA%20LINOLENIC%20ACID.aspx?activeIngredientId=805&activeIngredientName=GAMMA%20LINOLENIC%20ACID