Vitamin E restores reduced prostacyclin synthesis in aortic endothelial cells cultured with a high concentration of glucose

doi:10.1016/0026-0495(92)90053-D

Metabolism

Volume 41, Issue 6, June 1992, Pages 613-621

https://doi.org/10.1016/0026-0495(92)90053-D Get rights and content

Abstract

Reduced prostacyclin (PGI₂) production by the vascular wall may play an important role in the pathogenesis of vascular lesions such as atherosclerosis. The present study was undertaken to evaluate the effect of vitamin E on the production of PGI₂ and other prostaglandins (prostaglandin E₂ [PGE₂], thromboxane A₂ [TXA₂], and 15-hydroxyeicosatetraenoic acid [15-HETE]) by bovine aortic endothelial cells cultured in a high concentration of glucose (300 mg/dL). Compared with endothelial cells cultured in 100 mg/dL glucose, the production of PGI₂ and other prostaglandins, except 15-HETE, was significantly reduced in cultures containing 300 mg/dL glucose when stimulated by histamine, the Ca²⁺ ionophore, A23187, or human plasma-derived serum (PDS). The addition of vitamin E to each stimulant significantly restored the production of PGI₂, PGE₂, and TXA₂, products of the cyclo-oxygenase pathway, in aortic endothelial cells cultured in 300 mg/dL glucose. This effect of vitamin E on the stimulation of prostaglandin production was generally specific for d-α-tocopherol, but not for the other vitamin E analogs tested. However, vitamin E and the stimulants had no effect on the production of 15-HETE, a product of the lipoxygenase pathway. Moreover, vitamin E alone, without stimulants, did not affect prostaglandin production in cultured bovine aortic endothelial cells. These results suggest that vitamin E may restore reduced PGI₂, PGE₂, or TXA₂ production by bovine aortic endothelial cells cultured in a high concentration of glucose. It seems likely that vitamin E may restore depressed PGI₂ production by the vascular wall in hyperglycemic conditions such as those seen in patients with diabetes mellitus.

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^☆: Supported by the ONO Medical Research Foundation and a Grant-in-Aid for Scientific Research (No. 01570646) from the Ministry of Education, Science, and Culture of Japan.

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Vitamin E restores reduced prostacyclin synthesis in aortic endothelial cells cultured with a high concentration of glucose☆

Abstract

Biochem Med

Prostaglandins

Am J Clin Nutr

Prostaglandins

Diabetes Res Clin Pract

Atherosclerosis

Diabetes Res Clin Pract

Pros Leuko Med

Prostaglandins

Prostaglandins

Biochim Biophys Acta

J Biol Chem

Prostaglandins

Vitamin E and free radical peroxidation of lipids

Ann NY Acad Sci

An enzyme isolated from arteries transforms prostaglandin endoperoxides to an unstable substance that inhibits platelet aggregation

Nature

Unstable metabolites of arachidonic acid and their role in haemostasis and thrombosis

Br Med Bull

Human arterial and venous tissues generate prostacyclin (prostaglandin X), a potent inhibitor of platelet aggregation

Lancet

Decreased vascular prostacyclin in experimental diabetes

Life Sci

Decreased vascular prostacyclin in juvenile-onset diabetes

N Engl J Med