gamma-linolenic-acid and Scleroderma--Systemic

Evidence from biochemical studies and from experimental animals indicates that abnormalities of essential fatty acid (EFA) and eicosanoid metabolism could lead to salivary and lacrimal gland atrophy and to immunological and cardio-vascular defects. Measurements of EFA levels in erythrocytes from patients with primary Sjögren's syndrome have shown that abnormalities are indeed present. Controlled clinical trials of supplementation with gamma-linolenic acid (GLA) as evening primrose oil (Efamol) in both primary Sjögren's syndrome and systemic sclerosis have given positive results. There are strong arguments to indicate that sophisticated manipulation of EFA metabolism may have a role to play, not only in Sjögren's syndrome but also in other rheumatological disorders.

Topics: Erythrocyte Membrane; Fatty Acids, Essential; Fatty Acids, Unsaturated; gamma-Linolenic Acid; Humans; Linoleic Acids; Oenothera biennis; Plant Oils; Prostaglandins; Scleroderma, Systemic; Sjogren's Syndrome

Systemic sclerosis is a multi system disorder, for which there is no satisfactory treatment. Theoretically, dietary supplementation with essential fatty acids may lead to an increase in their derivatives, the vasoactive prostaglandins, which benefit the acute and chronic ischaemic lesions of this disease. We assessed the value of concentrated essential fatty acids in patients with systemic sclerosis, concentrating particularly on vascular symptoms and objective tests of vascular reactivity. Twenty-five patients with systemic sclerosis were randomised to receive concentrated essential fatty acids or placebo, for 6 months in a double-blind parallel group study. There was no significant difference between the active and placebo groups in terms of maximum blood flow after warming, minimum blood flow after cooling or the recovery time after cooling. There were no significant differences between the groups in the other parameters measured. Dietary essential fatty acids have no role in the treatment of vascular symptoms in established systemic sclerosis.

Topics: Adult; Aged; Blood Flow Velocity; Double-Blind Method; Female; gamma-Linolenic Acid; Humans; Laser-Doppler Flowmetry; Male; Middle Aged; Patient Compliance; Patient Satisfaction; Scleroderma, Systemic; Treatment Outcome

Drugs which modify the conversion of essential fatty acids to prostaglandins and leukotrienes are the mainstays of treatment in rheumatology. Yet these drugs have little or no action in scleroderma or Sjogren's syndrome and under some circumstances may have adverse effects. Patients with scleroderma have been shown to have very high levels of circulating prostaglandins, coupled with depletion of the prostaglandin precursors, dihomogammalinolenic acid and arachidonic acid. Levels of the metabolites of arachidonic acid, 22:4n-6 and 22:5n-6, which have major roles in maintaining normal cell membrane characteristics were exceptionally low in both plasma and red cell membranes. Others have observed that various functions are highly resistant to normal actions of PGs in scleroderma. This raises the possibility that the high rate of PG formation in scleroderma may be beneficial, in compensation, and that clinical symptoms develop when PG precursors begin to be depleted. Red cell membrane fatty acids patterns in Sjogren's syndrome are almost identical to those in scleroderma. Placebo-controlled trials of supplementation with essential fatty acids have been found to be beneficial in both scleroderma and Sjogren's syndrome.

Topics: Animals; Ascorbic Acid Deficiency; Connective Tissue Diseases; Cyclic AMP; Diabetes Mellitus; Fatty Acids, Essential; gamma-Linolenic Acid; Humans; Linolenic Acids; Prostaglandins; Scleroderma, Systemic; Sjogren's Syndrome