Effect of Evening Primrose Oil on Korean Patients With Mild Atopic Dermatitis: A Randomized, Double-Blinded, Placebo-Controlled Clinical Study

BACKGROUND: Atopic dermatitis (AD) is related to a deficiency of delta-6-desaturase, an enzyme responsible for converting linoleic acid to gamma-linolenic acid (GLA). Evening primrose oil (EPO) as a source of GLA has been of interest in the management of AD. OBJECTIVE: The aim of this randomized, double-blinded, placebo-controlled clinical study is to evaluate the efficacy and safety of EPO in Korean patients with AD. METHODS: Fifty mild AD patients with an Eczema Area Severity Index (EASI) score of 10 or less were enrolled and randomly divided into two groups. The first group received an oval unmarked capsule containing 450 mg of EPO (40 mg of GLA) per capsule, while placebo capsules identical in appearance and containing 450 mg of soybean oil were given to the other group. Treatment continued for a period of four months. EASI scores, transepidermal water loss (TEWL), and skin hydration were evaluated in all the AD patients at the baseline, and in months 1, 2, 3, and 4 of the study. RESULTS: At the end of month 4, the patients of the EPO group showed a significant improvement in the EASI score (p=0.040), whereas the patients of the placebo group did not. There was a significant difference in the EASI score between the EPO and placebo groups (p=0.010). Although not statistically significant, the TEWL and skin hydration also slightly improved in the EPO patients group. CONCLUSION: We suggest that EPO is a safe and effective medicine for Korean patients with mild AD.

Effect of gamma linolenic acid pretreatment on diabetic neuropathy in rats.

Background: The present study was planned to evaluate the preventive effects of gamma linolenic acid (GLA) on STZ induced diabetic neuropathy Methods: Streptozotocin (STZ) induced diabetic neuropathy in rats was monitored by measuring blood sugar levels, body weight, motor nerve conduction velocity (MNCV) and nociception. Forty rats were divided into 4 groups of 10 each. Group 1: control (vehicle), Group 2: STZ (50 mg/kg, i.v., single injection), Group 3: Gamma linolenic acid (50 mg/ kg, p.o., daily + STZ), Group 4: STZ + Insulin (4 units/kg, s.c., bid). Similar protocol was used for other parameters also. Results: Gamma linolenic acid pretreatment failed to reduce blood sugar levels in diabetic rats but prevented deterioration of motor nerve conduction velocity as compared to STZ diabetic rats. A significant weight gain was observed in STZ diabetic rats pretreated with GLA as compared to rats received STZ alone. Hyperalgesia induced by STZ was antagonized by GLA Conclusions: Thus gamma linolenic acid prevents the development of neuropathic changes induced by STZ in rats.

Effects of Gamma-Linolenic Acid for the Treatment of Acne Vulgaris Treated with Isotretinoin / 대한피부과학회지

BACKGROUND: Oral isotretinoin is an effective treatment modality for acne, but this agent may cause dryness of the skin and mucous membrane. Gamma-linolenic acid (GLA) has been known to improve skin moisture and reduce transepidermal water loss (TEWL). It is also known to have anti-inflammatory effects and to inhibit 5-alpha reductase. OBJECTIVE: This study was performed to evaluate the clinical efficacy of GLA in the prevention of xerosis and improvement of acne lesions after concomitant administration of isotretinoin. METHODS: In this prospective study, 102 Korean acne patients were enrolled and randomized to receive isotretinoin either with or without GLA for 12 weeks. Comparing evaluations included skin hydration, TEWL, visual analogue scale (VAS) score for dryness of the lips and skin, number of acne lesions such as comedos, papules, and pustules, Korean acne grading system (KAGS) grade, and patient satisfaction regarding treatment. RESULTS: The decrease of skin hydration and increase of the TEWL of the lips and cheek were less definite in the experimental group than those of the control group. VAS score for dryness of the lips and skin was significantly lower in the experimental group compared with the control group. The number of acne lesions decreased in both groups; only the numbers of papules were different between the two groups. The decrease of the KAGS grade was more definite in the experimental group than that in the control group. CONCLUSION: This study suggests that GLA could be used effectively for the improvement of acne lesions as well as for the prevention of xerosis.

Dose-Dependent Effects of Evening Primrose Oil in Children and Adolescents with Atopic Dermatitis

BACKGROUND: Previous clinical trials with evening primrose oil in atopic dermatitis (AD) treatment have shown different results. In addition, the optimal dose and duration of treatment with evening primrose oil have not yet been determined. OBJECTIVE: The aim of this study is to investigate the dose-response treatment effects of evening primrose oil on clinical symptoms of AD and serum concentrations of polyunsaturated fatty acids. METHODS: Forty AD patients were enrolled for the study and randomly divided into 2 groups: those who received evening primrose oil 160 mg daily for 8 weeks and those who received 320 mg of evening primrose oil twice daily for 8 weeks. We evaluated the Eczema Area Severity Index (EASI) scores of all AD patients at weeks 0, 2, 4 and 8. In addition, we measured the levels of serum fatty acids, including C16 : 0 (palmitic), C18 : 2n (linoleic), C18 : 3n (linolenic) and C20 : 4 (arachidonic acid) using gas chromatography. RESULTS: The serum fatty acid levels C18 : 3n and C20 : 4 were higher in the 320 mg group than in the 160 mg group, with statistical significance. After evening primrose oil treatment, EASI scores were reduced in the 2 groups. The improvement in EASI scores was greater in the 320 mg group than in the 160 mg group. There were no side effects seen in either group during the study in the 2 groups. CONCLUSION: The results of this study suggest that the 320 mg and 160 mg groups may be equally effective in treating AD patients and show dose-dependent effects on serum fatty acid levels and EASI scores.

Dose-Dependent Effects of Evening Primrose Oil in Children and Adolescents with Atopic Dermatitis

BACKGROUND: Previous clinical trials with evening primrose oil in atopic dermatitis (AD) treatment have shown different results. In addition, the optimal dose and duration of treatment with evening primrose oil have not yet been determined. OBJECTIVE: The aim of this study is to investigate the dose-response treatment effects of evening primrose oil on clinical symptoms of AD and serum concentrations of polyunsaturated fatty acids. METHODS: Forty AD patients were enrolled for the study and randomly divided into 2 groups: those who received evening primrose oil 160 mg daily for 8 weeks and those who received 320 mg of evening primrose oil twice daily for 8 weeks. We evaluated the Eczema Area Severity Index (EASI) scores of all AD patients at weeks 0, 2, 4 and 8. In addition, we measured the levels of serum fatty acids, including C16 : 0 (palmitic), C18 : 2n (linoleic), C18 : 3n (linolenic) and C20 : 4 (arachidonic acid) using gas chromatography. RESULTS: The serum fatty acid levels C18 : 3n and C20 : 4 were higher in the 320 mg group than in the 160 mg group, with statistical significance. After evening primrose oil treatment, EASI scores were reduced in the 2 groups. The improvement in EASI scores was greater in the 320 mg group than in the 160 mg group. There were no side effects seen in either group during the study in the 2 groups. CONCLUSION: The results of this study suggest that the 320 mg and 160 mg groups may be equally effective in treating AD patients and show dose-dependent effects on serum fatty acid levels and EASI scores.

Aeration effect on Spirulina platensis growth and ã-linolenic acid production

The influence of aeration on algal growth and gamma-linolenic acid (GLA) production in a bubble column photobioreactor was investigated. Studies were performed in a 20-L reactor at different aeration rates (0.2-2.5 vvm). Static, continuous, and periodic operation of air resulted in 41.9%, 88.4%, and 108% air saturation of dissolved oxygen, for which the corresponding values of GLA were 2.3, 6.5, and 7.5 mg·g-1 dry cell weight, respectively. An increase in the aeration rate from 0.2 to 2.5 vvm enhanced both the specific growth rate and GLA content under periodic sparging in the bicarbonate medium. With a 6-fold increase in the aeration rate, the GLA content of the alga increased by 69.64% (5.6-9.5 mg· g-1 dry cell weight). In addition, the total fatty acid (TFA) content in dry biomass increased from 2.22% to 4.41%, whereas the algae maintained a constant GLA to TFA ratio within the aeration rate tested. The dependence of GLA production on the aeration rate was explained by interrelating the GLA production rate with the specific growth rate using the Luedeking and Piret mixed growth model.

Gamma Linolenic Acid Exerts Anti-Inflammatory and Anti-Fibrotic Effects in Diabetic Nephropathy

PURPOSE: This study was undertaken to investigate the effects of gamma linolenic acid (GLA) on inflammation and extracellular matrix (ECM) synthesis in mesangial and tubular epithelial cells under diabetic conditions. MATERIALS AND METHODS: Sprague-Dawley rats were intraperitoneally injected with either a diluent [n=16, control (C)] or streptozotocin [n=16, diabetes (DM)], and eight rats each from the control and diabetic groups were treated with evening primrose oil by gavage for three months. Rat mesangial cells and NRK-52E cells were exposed to medium containing 5.6 mM glucose and 30 mM glucose (HG), with or without GLA (10 or 100 microM). Intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), and fibronectin (FN) mRNA and protein expression levels were evaluated. RESULTS: Twenty-four-hour urinary albumin excretion was significantly increased in DM compared to C rats, and GLA treatment significantly reduced albuminuria in DM rats. ICAM-1, MCP-1, FN mRNA and protein expression levels were significantly higher in DM than in C kidneys, and these increases were significantly abrogated by GLA treatment. In vitro, GLA significantly inhibited increases in MCP-1 mRNA expression and protein levels under high glucose conditions in HG-stimulated mesangial and tubular epithelial cells (p<0.05, respectively). ICAM-1 and FN expression showed a similar pattern to the expression of MCP-1. CONCLUSION: GLA attenuates not only inflammation by inhibiting enhanced MCP-1 and ICAM-1 expression, but also ECM accumulation in diabetic nephropathy.

The Effect of Isoflavone and Gamma-linolenic Acid Supplementation on Serum Lipids and Menopausal Symptoms in Postmenopausal Women

This study was performed to examine the combined effects of gamma linolenic acid and isoflavone supplementation on menopausal symptoms and serum lipids in 73 postmenopausal women. A total subjects were randomly assigned to isoflavone (30 mg) + gamma-linolenic acid (110 mg) group or placebo group. We measured menopausal symptoms by modified Kupperman Index (KI) and oxidized LDL, lipid peroxides, blood components and anthropometric parameters before and after the 12 week intervention period. After the 12 weeks of supplementation, supplement group and placebo group showed a significant reduction of modified kupperman index (p < 0.001). Isoflavone (30 mg) + gamma-linolenic acid (110 mg) supplement group showed a significant reduction of oxidized LDL cholesterol concentration (p = 0.006) whereas placebo group did not show significant change. Isoflavone and gamma-linolenic acid consumption did not significantly affect plasma concentrations of total, LDL, HDL cholesterol, triglyceride, apo A1, B and blood components. The result of present study demonstrated the supplementation of 30 mg isoflavone and 110 mg gamma-linolenic acid per day for 12 weeks may protect LDL cholesterol from oxidative stress.

Screening of microbial lipases and evalutaion of their potential to produce glycerides with high gamma linolenic acid concentration

Gamma-linolenic acid (GLA, 18:3, cis- 6,9,12-octadecatrienoic acid), an important compound in n-6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 percent of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially-available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from Geotrichum candidum as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7 percent of GLA in acylglycerols fraction when the borage oil was treated in a fixed-bed reactor for 24 hours at 30ºC.

Culture conditions stimulating high gama-Linolenic acid accumulation by Spirulina platensis / Condições de cultura simulando o levado acúmulo de ácido gama-linolênico por Spirulina platensis

Gamma-linolenic acid (GLA) production by Spirulina platensis under different stress-inducing conditions was studied. Submerged culture studies showed that low temperature (25ºC), strong light intensity (6 klux) and primrose oil supplement (0.8 percentw/v) induced 13.2 mg/g, 14.6 mg/g and 13.5 mg linolenic acid per gram dry cell weight respectively. A careful observation of fatty acid profile of the cyanobacteria shows that, oleic acid and linoleic acid, in experiments with varying growth temperature and oil supplements respectively, helped in accumulating excess γ-linolenic acid. In addition, cultures grown at increasing light regimes maintained the γ-linolenic acid to the total fatty acid ratio(GLA/TFA) constant, despite any change in γ-linolenic acid content of the cyanobacteria.

Estudou-se a produção de ácido γ-linolênico por Spirulina platensis em diferentes condições de estresse. Culturas submersas indicaram que temperatura baixa (25ºC), forte intensidade de luz (6 klux) e suplementação com óleo de prímula (0,8 por cento p/v) induziram a produção de ácido linolênico de 13,2 mg/g, 14,6 mg/g e 13,5 mg/g peso seco, respectivamente. Uma observação cuidadosa do perfil de ácidos graxos da cianobacteria indica que os ácidos oléico e linoléico, em experimentos com diferentes temperaturas de crescimento e suplementos de óleo, auxiliaram no acúmulo de excesso de ácido γ-linolênico. Além disso, as culturas obtidas em intensidades crescentes de luz mantiveram a relação ácido γ-linolênico/ácidos graxos totais constante, independentemente de qualquer mudança no conteúdo de ácido γ-linolênico da cianobactéria.

Gamma Linolenic Acid in Dry Eye

In this prospective study to evaluate the role of gamma linolenic acid in the management of dry eye, 100 patients of dry eyes were studied by dividing randomly into two groups of 50 each. In the test group, all the 50 patients were put on medication which consisted of cap gamma linolenic acid - 120 mg once daily dose, artificial tears solution/ointments 4-6 times daily with a topical mild steroid (loteprednol etabonate 0.5%) thrice daily. In the control group all the 50 patients were put on artificial tear solution/ointments and topical mild steroid (loteprednol etabonate 0.5%) thrice daily. All the patients were subjected to slit lamp examination, schirmer test, and fluorescien stain for tear film break up time (TBUT). In the test group symptomatic relief was shown by all 50 (100%) patients after one week of treatment. There was not much improvement in the schirmer test and TBUT results at 1 week. At 1 month follow up the result showed improvement and at 6 months there was definite increase in the schirmer test & TBUT values. The results were not influenced by the age & gender of the patients. In the control group though there was definite symptomatic relief in all the patients, but there was no change in the major study parameters i.e. tear film meniscus height; schirmer test and TBUT. At six month of the study there was marginal improvement of the major parameters but there was a lot of difference between the test and control groups. Thus gamma linolenic acid has a definite role in the management of dry eye.

Estudo dos componentes lipídicos das sementes de três espécies do gênero Cordia L. (Boraginaceae) / Lipids compounds study from seeds of three Cordia L. species (Boraginaceae)

Sementes de três espécies de Cordia L., da família Boraginaceae, coletadas em diferentes cidades do Estado de São Paulo foram analisadas quanto ao teor de lipídeos e composição de ácidos graxos, com ênfase na presença do ácido gama-linolênico, um ácido graxo de grande interesse terapêutico. Os lipídeos totais foram fracionados em classes (lipídeos neutros, fosfolipídeos e glicolipídeos) através de cromatografia em coluna aberta de gel de sílica e a composição de ácidos graxos foi determinada por cromatografia a gás. As concentrações de lipídeos totais apresentaram grande variação entre as amostras (25,84 a 62,81 por cento), sendo que a classe lipídica dominante foi de lipídeos neutros (média de 88,9 por cento dos lipídeos totais). Os ácidos insaturados representaram 75 por cento da composição total dos ácidos graxos, sendo o principal representante o ácido oléico. Verificou-se a presença do ácido gama-linolênico em todas as amostras analisadas, em concentrações que variaram de 0,63 a 2,54 por cento, valores superiores àqueles relatados pela literatura para outras espécies do gênero Cordia L.

Seeds of three Cordia L. species (Boraginaceae), collected in different cities of the State of São Paulo were analysed in relation to the lipid content and fatty acid composition, with emphasis on the presence of gamma-linolenic acid, a fatty acid with therapeutical interest. The total lipids were separated into classes (neutral lipids, phospholipids and glucolipids) by open column chromatography with silica gel and the fatty acid composition was determined by gas chromatography. Although the levels of total lipids varied considerably between samples (25.84 to 62.81 percent), the dominant class was that of neutral lipids (88.9 percent of the total lipids). The insaturated acids represented 75 percent of the total composition of fatty acids, with oleic acid being the main representative. The presence of gamma-linolenic acid was ascertained in all the samples analysed, in concentrations from 0.63 to 2.54 percent, higher values than those related in literature for other Cordia.

Effect of Dietary Oil Containing gamma-Linolenic Acid on the Plasma Lipid Levels and Thrombotic Activity in Rats

This study was carried out to determine the effect of dietary gamma-linolenic acid on decreasing the plasma lipid levels and the thrombotic activity in rats. Sprague-Dawley male rats (B.W 120 g) were fed a experimental diet containing 5% lard (46.05% saturated fatty acids) , corn oil (51.36% linoleic acid) , evening primrose oil (EPO,72.80% linoleic acid and 9.16% gamma-linolenic acid) or borage oil (BO,40.29% linoleic acid and 24.25% gamma-liolenic acid) for 30 days. Although there were no significant differences in the food intake among the groups, the body weight gain of the BO group was significantly lower than that of the other groups. The bleeding time of the BO group was significantly longer than that of the other groups. There were significantly differences in the whole blood clotting time among the groups except for the EPO and corn oil groups, where the whole blood clotting time of the BO group was the highest among the groups, and that of the lard group was the lowest. The plasma triacyglyceride (TAG) , total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) concentrations were the lowest in the BO group, but highest in the lard group, and there were significant differences among the groups. The plasma HDL-C concentrations were in the following order: BO, EPO, corn oil and lard groups and there were significant differences among the groups. The excretions of fecal neutial steroids and acidic steroids of the BO group were the highest among the groups, and there were significant differences compared to the other groups. The results suggest that dietary EPO and BO containing gamma-linolenic acid has an antithrombotic activity, and inhibits the increasing of plasma TAG, TC and LDL-C concentrations compared to lard, which contains saturated fatty acids, or corn oil, which contains linoleic acid.