A cell aggregation model for the protective effect of selenium and vitamin E on methylmercury toxicity

SummaryThe effect of alfa-tocopherol on the cell-cell interactions at the vessel wall were studied, using an in vitro model of human umbilical vein endothelial cell cultures (HUEC). Immune triggered granulocytes (PMN) will adhere to and damage HUEC and platelets enhance this PMN mediated endothelial injury. When HUEC are cultured in the presence of vitamin E, 51Cr-leakage induced by complement stimulated PMN is significantly decreased and the enhanced cytotoxicity by platelets is completely abolished (p <0.001).The inhibition of PMN induced endothelial injury is directly correlated to a diminished adherence of PMN to vitamin E- cultured HUEC (p <0.001), which may be mediated by an increase of both basal and stimulated endogenous prostacyclin (PGI2) from alfa-tocopherol-treated HUEC (p <0.025). The vitamin E-effect is abolished by incubation of HUEC with the irreversible cyclo-oxygenase inhibitor, acetylsalicylic acid, but the addition of exogenous PGI2 could not reproduce the vitamin E-mediated effects.We conclude that vitamin E exerts a protective effect on immune triggered endothelial damage, partly by increasing the endogenous anti-oxidant potential, partly by modulating intrinsic endothelial prostaglandin production. The failure to reproduce vitamin E-protection by exogenously added PGI2 may suggest additional, not yet elucidated vitamin E-effects on endothelial metabolism.

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Protective effect of vitamin E on lymphocyte growth capacity during incubation in vitro

Mechanisms of Ageing and Development ◽

10.1016/0047-6374(95)01595-q ◽

1995 ◽

Vol 82 (2-3) ◽

pp. 129-148 ◽

Cited By ~ 5

Author(s):

Ke-Yin Tu ◽

Randall Matthews ◽

Kathleen S. Matthews

Keyword(s):

Vitamin E ◽

Protective Effect ◽

Growth Capacity ◽

Lymphocyte Growth

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Protective effect of combined systemic ascorbic acid (vitamin C) and d-a-tocopherol (vitamin E) against sunburn in patients with malignant melanoma (MM)

Melanoma Research ◽

10.1097/00008390-199706001-00270 ◽

1997 ◽

Vol 7 (Supplement 1) ◽

pp. S77

Author(s):

M Placzek ◽

B Eberlein-Konig ◽

B Przybilla

Keyword(s):

Ascorbic Acid ◽

Vitamin E ◽

Malignant Melanoma ◽

Vitamin C ◽

Protective Effect

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Protective Effect of Vitamin E Against Hepato-nephrotoxic Oxidative Stress Induced by Isoprinosine Toxicity

Indian Journal of Public Health Research & Development ◽

10.37506/ijphrd.v11i4.5398 ◽

2020 ◽

Keyword(s):

Oxidative Stress ◽

Vitamin E ◽

Protective Effect

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Modulation by Heparin of the Interaction of the A1 Domain of von Willebrand Factor With Glycoprotein Ib

Blood ◽

10.1182/blood.v94.12.4186 ◽

1999 ◽

Vol 94 (12) ◽

pp. 4186-4194 ◽

Cited By ~ 9

Author(s):

Christelle Perrault ◽

Nadine Ajzenberg ◽

Paulette Legendre ◽

Ghassem Rastegar-Lari ◽

Dominique Meyer ◽

...

Keyword(s):

Von Willebrand Factor ◽

Cell Aggregation ◽

Cell Aggregates ◽

Critical Determinant ◽

Amino Terminal ◽

A Cell ◽

A1 Domain ◽

Von Willebrand ◽

Willebrand Factor ◽

Amino Terminal Fragment

Abstract The conformation of the A1 domain of von Willebrand factor (vWF) is a critical determinant of its interaction with the glycoprotein (GP) Ib/V/IX complex. To better define the regulatory mechanisms of vWF A1 domain binding to the GPIb/V/IX complex, we studied vWF-dependent aggregation properties of a cell line overexpressing the GPIb, GPIbβ, and GPIX subunits (CHO-GPIbβ/IX cells). We found that CHO-GPIbβ/IX cell aggregation required the presence of both soluble vWF and ristocetin. Ristocetin-induced CHO-GPIbβ/IX cell aggregation was completely inhibited by the recombinant VCL fragment of vWF that contains the A1 domain. Surprisingly, the substitution of heparin for ristocetin resulted in the formation of CHO-GPIbβ/IX cell aggregates. Using monoclonal antibodies blocking vWF interaction with GPIb/V/IX or mocarhagin, a venom metalloproteinase that removes the amino-terminal fragment of GPIb extending from aa 1 to 282, we demonstrated that both ristocetin- and heparin-induced aggregations involved an interaction between the A1 domain of vWF and the GPIb subunit of the GPIb/V/IX complex. The involvement of heparin in cell aggregation was also demonstrated after treatment of heparin with heparinase that abolished CHO-GPIbβ/IX cell aggregation. These results indicated that heparin was able to induce vWF-dependent CHO-GPIbβ/IX cell aggregation. In conclusion, we demonstrated that heparin is capable of positively modulating the vWF interaction with the GPIb/V/IX complex.

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