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α-Tocopherol Improves Microcirculatory Dysfunction on Fructose Fed Hamsters.

Boa BC, Barros CM, Souza Md, Castiglione RC, Cyrino FZ, Bouskela E - PLoS ONE (2015)

Bottom Line: On the other hand, vitamin E supplementation resulted in increased responses for both water and fructose drinking groups (177.4% for F vs.The number of leaky sites after I/R and histamine stimuli in vitamin E supplemented animals decreased (-25.1% and -15.3% for F vs.Our results strongly suggest that vitamin E could improve the endothelial function and permeability barrier and also reverse impairments elicited by sugar overload.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, Brazil.

ABSTRACT
Fructose, an everyday component of western diet associated to chronic hyperglycemia and enhanced free radical production, impairs endothelial function and supplementation with antioxidants might improve it. In this study we investigated if vitamin E could reverse the microvascular damage elicited by fructose. Male Syrian golden hamsters drank either 10% fructose solution (F) or filtered water (C), combined with three concentrations of vitamin E in their chows [zero, normal (VE) or 5X (5XVE)] during 60 days. Microvascular reactivity in response to topical application of acetylcholine (Ach; endothelium-dependent vasodilator) or sodium nitroprusside (SNP; endothelium-independent vasodilator) and macromolecular permeability increase induced by either 30 min ischemia followed by reperfusion (I/R) or topical application of histamine (5 μM) were assessed using the cheek pouch preparation. Compared to controls (drinking filtered water), fructose-drinking animals showed decreased vasodilatation to acetylcholine in all concentrations tested (-56.2% for 10-9M, -53.9% for 10-7M and -43.7% for 10-5M). On the other hand, vitamin E supplementation resulted in increased responses for both water and fructose drinking groups (177.4% for F vs. F/5XVE and 241.6% for C vs. C/5XVE for 10-5M Ach). Endothelial-independent vasodilatation explored by topical application of SNP was restored and even enhanced with the supplementation of 5X vitamin E in both groups (80.1% for F vs. F/5XVE; 144.2% for C vs. C/5XVE; 3.4% of difference for C/5XVE vs. F/5XVE on 10-5M SNP). The number of leaky sites after I/R and histamine stimuli in vitamin E supplemented animals decreased (-25.1% and -15.3% for F vs. F/5XVE; and -21.7% and -16% of leaky sites comparing C vs. C/5XVE, respectively for I/R and histamine stimuli) pointing to tightening of the endothelial barrier for macromolecular permeability. Our results strongly suggest that vitamin E could improve the endothelial function and permeability barrier and also reverse impairments elicited by sugar overload.

No MeSH data available.


Related in: MedlinePlus

Mean arteriolar diameters after topical application of Ach–Endothelial- dependent evaluation.Data are shown as changes of average diameter, expressed as mean ± SD and plotted in superimposed symbols. (A) Overall mean arteriolar diameters after topical application of three concentrations of acetylcholine (10−9, 10−7 and 10−5 M) in the 2 treated groups. (B) Endothelial-dependent responses of groups treated with filtered water, concomitantly associated with chows without vitamin E (C), with normal concentration of vitamin E (75U/kg–C/VE) and supplemented concentrations of vitamin E (375U/kg–C/5XVE). (C) Endothelial-dependent responses of groups that had the filtered water substituted by 10% fructose solution, concomitantly associated with chows without vitamin E (F), with normal concentration of vitamin E (75U/kg–F/VE) and supplemented concentrations of vitamin E (375U/kg–F/5XVE). +Significantly different in relation to control; +p<0.05 [10-7M] and both control and control with normal concentration of vitamin E; +p<0.01 [10-5M]. #Significantly different from fructose-drinking without vitamin E in chow (#p<0.05).
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pone.0134740.g002: Mean arteriolar diameters after topical application of Ach–Endothelial- dependent evaluation.Data are shown as changes of average diameter, expressed as mean ± SD and plotted in superimposed symbols. (A) Overall mean arteriolar diameters after topical application of three concentrations of acetylcholine (10−9, 10−7 and 10−5 M) in the 2 treated groups. (B) Endothelial-dependent responses of groups treated with filtered water, concomitantly associated with chows without vitamin E (C), with normal concentration of vitamin E (75U/kg–C/VE) and supplemented concentrations of vitamin E (375U/kg–C/5XVE). (C) Endothelial-dependent responses of groups that had the filtered water substituted by 10% fructose solution, concomitantly associated with chows without vitamin E (F), with normal concentration of vitamin E (75U/kg–F/VE) and supplemented concentrations of vitamin E (375U/kg–F/5XVE). +Significantly different in relation to control; +p<0.05 [10-7M] and both control and control with normal concentration of vitamin E; +p<0.01 [10-5M]. #Significantly different from fructose-drinking without vitamin E in chow (#p<0.05).

Mentions: Fructose ingestion resulted in significant alterations of endothelial cell function, observed by decreased vasodilatation to acetylcholine (ACh–Fig 2), in all concentrations topically applied. Although the treatment with vitamin E did not change the relationship between control and fructose-drinking responses, it was possible to observe an increment in the responses dependent on vitamin E concentration in the fructose-drinking group [Ach 10-5M - (F/5XVE vs. F– 63.9% difference in the response) and (F/5XVE vs. F/VE– 31.7% difference in the response); Fig 2C]. Moreover the amelioration of the response was not limited to fructose-drinking animals, but the control groups also showed an improvement in endothelial function dependent on vitamin E concentration [Ach 10-5M (C/5XVE vs. C– 70.7% difference in the response) and (C/5XVE vs. C/VE– 41.8% difference in the response).


α-Tocopherol Improves Microcirculatory Dysfunction on Fructose Fed Hamsters.

Boa BC, Barros CM, Souza Md, Castiglione RC, Cyrino FZ, Bouskela E - PLoS ONE (2015)

Mean arteriolar diameters after topical application of Ach–Endothelial- dependent evaluation.Data are shown as changes of average diameter, expressed as mean ± SD and plotted in superimposed symbols. (A) Overall mean arteriolar diameters after topical application of three concentrations of acetylcholine (10−9, 10−7 and 10−5 M) in the 2 treated groups. (B) Endothelial-dependent responses of groups treated with filtered water, concomitantly associated with chows without vitamin E (C), with normal concentration of vitamin E (75U/kg–C/VE) and supplemented concentrations of vitamin E (375U/kg–C/5XVE). (C) Endothelial-dependent responses of groups that had the filtered water substituted by 10% fructose solution, concomitantly associated with chows without vitamin E (F), with normal concentration of vitamin E (75U/kg–F/VE) and supplemented concentrations of vitamin E (375U/kg–F/5XVE). +Significantly different in relation to control; +p<0.05 [10-7M] and both control and control with normal concentration of vitamin E; +p<0.01 [10-5M]. #Significantly different from fructose-drinking without vitamin E in chow (#p<0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4526657&req=5

pone.0134740.g002: Mean arteriolar diameters after topical application of Ach–Endothelial- dependent evaluation.Data are shown as changes of average diameter, expressed as mean ± SD and plotted in superimposed symbols. (A) Overall mean arteriolar diameters after topical application of three concentrations of acetylcholine (10−9, 10−7 and 10−5 M) in the 2 treated groups. (B) Endothelial-dependent responses of groups treated with filtered water, concomitantly associated with chows without vitamin E (C), with normal concentration of vitamin E (75U/kg–C/VE) and supplemented concentrations of vitamin E (375U/kg–C/5XVE). (C) Endothelial-dependent responses of groups that had the filtered water substituted by 10% fructose solution, concomitantly associated with chows without vitamin E (F), with normal concentration of vitamin E (75U/kg–F/VE) and supplemented concentrations of vitamin E (375U/kg–F/5XVE). +Significantly different in relation to control; +p<0.05 [10-7M] and both control and control with normal concentration of vitamin E; +p<0.01 [10-5M]. #Significantly different from fructose-drinking without vitamin E in chow (#p<0.05).
Mentions: Fructose ingestion resulted in significant alterations of endothelial cell function, observed by decreased vasodilatation to acetylcholine (ACh–Fig 2), in all concentrations topically applied. Although the treatment with vitamin E did not change the relationship between control and fructose-drinking responses, it was possible to observe an increment in the responses dependent on vitamin E concentration in the fructose-drinking group [Ach 10-5M - (F/5XVE vs. F– 63.9% difference in the response) and (F/5XVE vs. F/VE– 31.7% difference in the response); Fig 2C]. Moreover the amelioration of the response was not limited to fructose-drinking animals, but the control groups also showed an improvement in endothelial function dependent on vitamin E concentration [Ach 10-5M (C/5XVE vs. C– 70.7% difference in the response) and (C/5XVE vs. C/VE– 41.8% difference in the response).

Bottom Line: On the other hand, vitamin E supplementation resulted in increased responses for both water and fructose drinking groups (177.4% for F vs.The number of leaky sites after I/R and histamine stimuli in vitamin E supplemented animals decreased (-25.1% and -15.3% for F vs.Our results strongly suggest that vitamin E could improve the endothelial function and permeability barrier and also reverse impairments elicited by sugar overload.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, Brazil.

ABSTRACT
Fructose, an everyday component of western diet associated to chronic hyperglycemia and enhanced free radical production, impairs endothelial function and supplementation with antioxidants might improve it. In this study we investigated if vitamin E could reverse the microvascular damage elicited by fructose. Male Syrian golden hamsters drank either 10% fructose solution (F) or filtered water (C), combined with three concentrations of vitamin E in their chows [zero, normal (VE) or 5X (5XVE)] during 60 days. Microvascular reactivity in response to topical application of acetylcholine (Ach; endothelium-dependent vasodilator) or sodium nitroprusside (SNP; endothelium-independent vasodilator) and macromolecular permeability increase induced by either 30 min ischemia followed by reperfusion (I/R) or topical application of histamine (5 μM) were assessed using the cheek pouch preparation. Compared to controls (drinking filtered water), fructose-drinking animals showed decreased vasodilatation to acetylcholine in all concentrations tested (-56.2% for 10-9M, -53.9% for 10-7M and -43.7% for 10-5M). On the other hand, vitamin E supplementation resulted in increased responses for both water and fructose drinking groups (177.4% for F vs. F/5XVE and 241.6% for C vs. C/5XVE for 10-5M Ach). Endothelial-independent vasodilatation explored by topical application of SNP was restored and even enhanced with the supplementation of 5X vitamin E in both groups (80.1% for F vs. F/5XVE; 144.2% for C vs. C/5XVE; 3.4% of difference for C/5XVE vs. F/5XVE on 10-5M SNP). The number of leaky sites after I/R and histamine stimuli in vitamin E supplemented animals decreased (-25.1% and -15.3% for F vs. F/5XVE; and -21.7% and -16% of leaky sites comparing C vs. C/5XVE, respectively for I/R and histamine stimuli) pointing to tightening of the endothelial barrier for macromolecular permeability. Our results strongly suggest that vitamin E could improve the endothelial function and permeability barrier and also reverse impairments elicited by sugar overload.

No MeSH data available.


Related in: MedlinePlus