Evening primrose oil

Identification

Name
Evening primrose oil
Accession Number
DB11358
Type
Small Molecule
Groups
Investigational, Nutraceutical
Description

Evening primrose oil comes from the extraction from Oenothera biennis seeds and it is commonly used as an alternative source for omega-6 essential fatty acids. In its composition it presents some fatty acids such as Alpha-Linolenic Acid and Gamolenic acid.[1] Evening primrose oil has been filled for the FDA by Humanetics Corporation on April 2000 to be a new dietary ingredient but its current status is "Inadequate basis for expectation of safety".[5] By Health Canada, evening primrose oil is approved in over-the-counter combination dietary supplements.[6] By the EMA, evening primrose oil is approved in herbal preparations.[7]

Synonyms
  • Oenothera biennis (evening primrose) oil
  • Oenothera biennis (evening primrose) seed extract
  • Oenothera biennis l. oil
  • Oenothera biennis seed extract
  • Oenothera biennis seed oil
  • Oenothera lamarckiana l. oil
  • Oenothera muricata seed oil
  • Oenothera oil
  • Oenothera pycnocarpa seed oil
  • Oenotherae biennis oleum
  • Oils, glyceridic, evening primrose
  • Oleum oenotherae erythrospinae
  • Primrose oil
Mixture Products
NameIngredientsDosageRouteLabellerMarketing StartMarketing End
Efamol CapEvening primrose oil (.6 ml) + Vitamin E (13.6 unit)CapsuleOralEfamol Research Inc.1982-12-311999-10-25Canada
Evening Primrose Oil CapEvening primrose oil (500 mg) + Vitamin E (13.6 unit)CapsuleOralNature's Way Of Canada Ltd.1984-12-312004-07-26Canada
Evening Primrose Oil With Vitamin EEvening primrose oil (500 mg/1) + Vitamin E (15 unit/1)CapsuleOralAshbury Research CorporationNot applicableNot applicableCanada
Gamma OilEvening primrose oil (500 mg) + Vitamin E (14.9 unit)CapsuleOralQuest Vitamins A Div Of Purity Life Health Products1985-12-312000-07-20Canada
Rhodd Ato Repair Body So ApEvening primrose oil (6.0 g/100g) + Chamaecyparis obtusa leaf (2.0 g/100g) + Olive oil (13.0 g/100g)SoapTopicalSJ NATURAL2018-08-01Not applicableUs
Unapproved/Other Products
NameIngredientsDosageRouteLabellerMarketing StartMarketing End
VP-PrecipEvening primrose oil (500 mg/1) + Bilberry (40 mg/1) + Linseed oil (1000 mg/1)Capsule, gelatin coatedOralVirtus Pharmaceuticals2012-05-182016-03-03Us
Categories
UNII
3Q9L08K71N
CAS number
308064-97-3
Weight
Not Available
Chemical Formula
Not Available
InChI Key
Not Available
InChI
Not Available
IUPAC Name
Not Available
SMILES
Not Available

Pharmacology

Indication

Evening primrose oil is used as part of over-the-counter dietary supplements.[6]

It is also used for the treatment of systemic inflammatory diseases and for women's health conditions such as cyclical mastalgia. These indications do not have sufficient evidence of their effectiveness. It was used for the treatment of atopic dermatitis in the United Kingdom but it is currently withdrawn due to lack of evidence of effectiveness.[1]

Associated Therapies
Pharmacodynamics

The effectivity of evening primrose oil is debatable as the evidence is very limited.[9] Evening primrose oil improves the essential fatty acid content in plasma, erythrocyte, and platelet lipids. It has also been registered to increase alpha-tocopherol levels in non-diabetic and type I diabetic patients. Evening primrose oil affects the fatty acid composition of serum lipids and adipose tissue as well as it helps maintain normal cellular structures and it serves as a prostaglandin precursor. Administration of evening primrose oil is part of long-term therapy and thus, immediate results are never expected.[4]

Mechanism of action

Evening primrose oil presents a content of 74% Alpha-Linolenic Acid and 9% Gamolenic acid from which the later seems to be the key active ingredient of this oil. These major essential fatty acids are required for the normal structure of cell membranes and they are not synthesized endogenously.[4] The therapeutic activity of evening primrose oil is attributed to the direct action of its essential fatty acids on immune cells as well as to an indirect effect on the synthesis of eicosanoids. The actions of highly unsaturated fatty acids in tissues and eicosanoids are thought to be implicated in inflammatory and immunologic pathogeneses.[1]

The essential fatty acids found in evening primrose oil are involved in the biosynthesis of prostaglandin. For this activity, the main involved component is the Gamolenic acid. The presence of this essential fatty acid allows the synthesis of anti-inflammatory substances such as 15-hydroxy-eicosatrienoic acid and prostaglandin E1.[4]

Absorption

The pharmacokinetics of evening primrose oil is mainly studied by analyzing its active ingredient Gamolenic acid. After administration, Gamolenic acid is rapidly absorbed and converted directly to Dihomo-gamma-linolenic acid and other precursors.[4] When orally administered, the tmax was directly dependent to the time of administration, being of 2.7 hours in the evening and 4.4 hours in the morning. The Cmax and AUC were registered to be approximately 21 mcg/ml and 274 mcg.h/ml.[2] The bioavailability of Gamolenic acid acid is influenced by triglyceride composition, cellular kinetics of phospholipases and acyltransferases.[3]

Volume of distribution

No pharmacokinetic data available.

Protein binding

No pharmacokinetic data available.

Metabolism

The main component of evening primrose oil, Alpha-Linolenic Acid is usually desaturated by delta-6-desaturase which transforms this fatty acid to Gamolenic acid. This metabolic activity usually is limited by external factors such as stress, aging, alcohol, smoking, inflammation, diabetes, etc. In presence of these circumstances, the linoleic acid gets accumulated in the body and it inhibits the activity of the enzyme delta-6-desaturase. In proper conditions, Gamolenic acid forms Dihomo-gamma-linolenic acid by the action of elongases and it can further act as a substrate for production of prostaglandins or to be denaturated to arachidonic acid.[4]

Route of elimination

The major components of the primrose oil are highly metabolized and the majority of the generated metabolites are excreted in the urine.[8]

Half life

No pharmacokinetic data available.

Clearance

No pharmacokinetic data available.

Toxicity

Evening primrose oil seems to have little toxicological effect in humans. The reported LD50 values in the mouse are 3.12 x 10^4 mcg/kg. The toxicological effects are very minimal and it has proven to not have an effect on tumor incidence nor to present effects on fertility studies.[9]

Affected organisms
  • Humans and other mammals
Pathways
Not Available
Pharmacogenomic Effects/ADRs
Not Available

Interactions

Drug Interactions
DrugInteraction
7-NitroindazoleThe therapeutic efficacy of 7-Nitroindazole can be decreased when used in combination with Evening primrose oil.
AbacavirAbacavir may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AcarboseAcarbose may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AceclofenacAceclofenac may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AcemetacinAcemetacin may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AcetaminophenAcetaminophen may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AcetazolamideThe therapeutic efficacy of Acetazolamide can be decreased when used in combination with Evening primrose oil.
Acetylsalicylic acidAcetylsalicylic acid may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AclidiniumAclidinium may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
AcrivastineAcrivastine may decrease the excretion rate of Evening primrose oil which could result in a higher serum level.
Food Interactions
Not Available

References

General References
  1. Bayles B, Usatine R: Evening primrose oil. Am Fam Physician. 2009 Dec 15;80(12):1405-8. [PubMed:20000302]
  2. Martens-Lobenhoffer J, Meyer FP: Pharmacokinetic data of gamma-linolenic acid in healthy volunteers after the administration of evening primrose oil (Epogam). Int J Clin Pharmacol Ther. 1998 Jul;36(7):363-6. [PubMed:9707349]
  3. Fan YY, Chapkin RS, Ramos KS: Dietary lipid source alters murine macrophage/vascular smooth muscle cell interactions in vitro. J Nutr. 1996 Sep;126(9):2083-8. doi: 10.1093/jn/126.9.2083. [PubMed:8814195]
  4. Wollschlaeger B. (2003). The ABC Clinical Guide to Herbs. American botanical council.
  5. FDA new dietary ingredients [Link]
  6. Health Canada [Link]
  7. EMA [Link]
  8. Gamma-linolenic acid monograph [File]
  9. Chemical Information Document of the National Toxicology Program [File]
External Links
PubChem Substance
347911198
Wikipedia
Evening_primrose_oil
MSDS
Download (46.8 KB)

Clinical Trials

Clinical Trials
PhaseStatusPurposeConditionsCount
3RecruitingTreatmentMissed Abortion1
4CompletedTreatmentAtopic Dermatitis (AD) / Neurodermatitis1
4CompletedTreatmentBenign Breast Disease / Fibroadenoma / Fibrocystic Disease of Breast / Mastodynia1

Pharmacoeconomics

Manufacturers
Not Available
Packagers
Not Available
Dosage forms
FormRouteStrength
CapsuleOral
SoapTopical
Capsule, gelatin coatedOral
Prices
Not Available
Patents
Not Available

Properties

State
Liquid
Experimental Properties
PropertyValueSource
boiling point (°C)240 ºC'MSDS'
water solubilityInsoluble'MSDS'
logP7National Toxicology Program.
Predicted Properties
Not Available
Predicted ADMET features
Not Available

Spectra

Mass Spec (NIST)
Not Available
Spectra
Not Available

Taxonomy

Classification
Not classified

Enzymes

Kind
Protein
Organism
Human
Pharmacological action
No
General Function
Catalyzes the first and rate-limiting reaction of the four that constitute the long-chain fatty acids elongation cycle. This endoplasmic reticulum-bound enzymatic process, allows the addition of 2 carbons to the chain of long- and very long-chain fatty acids/VLCFAs per cycle. Condensing enzyme that acts specifically toward polyunsaturated acyl-CoA with the higher activity toward C18:3(n-6) acyl-CoA. May participate in the production of monounsaturated and of polyunsaturated VLCFAs of different chain lengths that are involved in multiple biological processes as precursors of membrane lipids and lipid mediators.
Specific Function
3-oxo-arachidoyl-coa synthase activity
Gene Name
ELOVL5
Uniprot ID
Q9NYP7
Uniprot Name
Elongation of very long chain fatty acids protein 5
Molecular Weight
35293.15 Da
References
  1. Wollschlaeger B. (2003). The ABC Clinical Guide to Herbs. American botanical council.
Kind
Protein
Organism
Human
Pharmacological action
No
General Function
Oxidoreductase activity
Specific Function
Isoform 2 does not exhibit any catalytic activity toward 20:3n-6, but it may enhance FADS2 activity (By similarity). Isoform 1 is a component of a lipid metabolic pathway that catalyzes biosynthesi...
Gene Name
FADS1
Uniprot ID
O60427
Uniprot Name
Fatty acid desaturase 1
Molecular Weight
51963.945 Da
References
  1. Wollschlaeger B. (2003). The ABC Clinical Guide to Herbs. American botanical council.
Kind
Protein
Organism
Human
Pharmacological action
Unknown
General Function
Stearoyl-coa 9-desaturase activity
Specific Function
Component of a lipid metabolic pathway that catalyzes biosynthesis of highly unsaturated fatty acids (HUFA) from precursor essential polyunsaturated fatty acids (PUFA) linoleic acid (LA) (18:2n-6) ...
Gene Name
FADS2
Uniprot ID
O95864
Uniprot Name
Fatty acid desaturase 2
Molecular Weight
52259.075 Da
References
  1. Wollschlaeger B. (2003). The ABC Clinical Guide to Herbs. American botanical council.

Drug created on December 03, 2015 09:52 / Updated on November 02, 2018 07:09