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Correlations between Endothelial Functions and ROS Detection in Diabetic Microvascular Wall: Early and Late Ascorbic Acid Supplementation.

Sridulyakul P, Wongeak-In N, Patumraj S - Int J Vasc Med (2012)

Bottom Line: On 12th week after STZ injection, the findings showed that in DM group, Ach (10(-5) M)-induced vasodilatation was decreased, while the number of leukocyte adhesion was increased significantly (P < 0.01).By using dihydrorhodamine 123, our findings also indicated that the existing of ROS productions on diabetic arteriolar and venular walls were different significantly (ROS(arteriole) = 165.89 ± 24.59 and ROS(venule) = 172.26 ± 34.70) (P < 0.05).Moreover by using BH4 inhibitor to induce increase in arteriolar ROS, the results also confirmed that AA could improve endothelial function with closed correlation to its potential to reduce vascular ROS content.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand.

ABSTRACT
The correlation between endothelial function and reactive oxygen species detecting from diabetic microvascular wall and the antioxidant effect of ascorbic acid (AA) during early and late phases of diabetic induction were determined. Male Spraque-Dawley rats were divided into four groups: control, diabetes rats (DM, using iv.injection of 55 mg/kg BW streptozotocin, (STZ)), and two groups of DM rats treated with AA (1 g/L, (STZ)) starting on day 2 (DM + AAday2) and week 6th (DM + AA6wk). On 12th week after STZ injection, the findings showed that in DM group, Ach (10(-5) M)-induced vasodilatation was decreased, while the number of leukocyte adhesion was increased significantly (P < 0.01). Interestingly, these abnormalities induced by DM could be protected or improved in both AA-treated groups, DM + AAday2 and DM + AA6wk. By using dihydrorhodamine 123, our findings also indicated that the existing of ROS productions on diabetic arteriolar and venular walls were different significantly (ROS(arteriole) = 165.89 ± 24.59 and ROS(venule) = 172.26 ± 34.70) (P < 0.05). Moreover by using BH4 inhibitor to induce increase in arteriolar ROS, the results also confirmed that AA could improve endothelial function with closed correlation to its potential to reduce vascular ROS content.

No MeSH data available.


Related in: MedlinePlus

Experimental protocol for measuring ROS content and vascular response to Ach (acetylcholine) as the effect of AA (ascorbic acid) and/or 6R-BH4 (6R-5,6,7,8-tetrahydro-L-biopterin dihydrochloride) application after inhibiting BH4 biosynthetic by DAHP (2,4-diamino-6-hydroxypyrimidine). There are four groups: control (CON + vehicle), control treated with DAHP (CON + DAHP), control treated with DAHP with ascorbic acid (CON + DAHP + AA), and control treated with DAHP with ascorbic acid and BH4 (CON + DAHP + AA + BH4).
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Related In: Results  -  Collection


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fig1: Experimental protocol for measuring ROS content and vascular response to Ach (acetylcholine) as the effect of AA (ascorbic acid) and/or 6R-BH4 (6R-5,6,7,8-tetrahydro-L-biopterin dihydrochloride) application after inhibiting BH4 biosynthetic by DAHP (2,4-diamino-6-hydroxypyrimidine). There are four groups: control (CON + vehicle), control treated with DAHP (CON + DAHP), control treated with DAHP with ascorbic acid (CON + DAHP + AA), and control treated with DAHP with ascorbic acid and BH4 (CON + DAHP + AA + BH4).

Mentions: To inhibit intracellular BH4 levels, we applied DAHP (20 mM; 1 mL/5 min for 30 min), in order to diminish NO production. In the presence of DAHP, vascular response to Ach (10 μM; 1 mL/5 min) was obtained after application of AA (2.6 mM; 10 mL/1 min) plus 6R-BH4 (0.1 mM; 1 mL/5 min for 10 min). Moreover, the arterial ROS content was also detected using DHR-fluorescent probe (dihydrorhodamine 123 Sigma Chemical Co., USA) (10 μmole/L) as well. The experimental protocol of each group was shown in Figure 1.


Correlations between Endothelial Functions and ROS Detection in Diabetic Microvascular Wall: Early and Late Ascorbic Acid Supplementation.

Sridulyakul P, Wongeak-In N, Patumraj S - Int J Vasc Med (2012)

Experimental protocol for measuring ROS content and vascular response to Ach (acetylcholine) as the effect of AA (ascorbic acid) and/or 6R-BH4 (6R-5,6,7,8-tetrahydro-L-biopterin dihydrochloride) application after inhibiting BH4 biosynthetic by DAHP (2,4-diamino-6-hydroxypyrimidine). There are four groups: control (CON + vehicle), control treated with DAHP (CON + DAHP), control treated with DAHP with ascorbic acid (CON + DAHP + AA), and control treated with DAHP with ascorbic acid and BH4 (CON + DAHP + AA + BH4).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3368388&req=5

fig1: Experimental protocol for measuring ROS content and vascular response to Ach (acetylcholine) as the effect of AA (ascorbic acid) and/or 6R-BH4 (6R-5,6,7,8-tetrahydro-L-biopterin dihydrochloride) application after inhibiting BH4 biosynthetic by DAHP (2,4-diamino-6-hydroxypyrimidine). There are four groups: control (CON + vehicle), control treated with DAHP (CON + DAHP), control treated with DAHP with ascorbic acid (CON + DAHP + AA), and control treated with DAHP with ascorbic acid and BH4 (CON + DAHP + AA + BH4).
Mentions: To inhibit intracellular BH4 levels, we applied DAHP (20 mM; 1 mL/5 min for 30 min), in order to diminish NO production. In the presence of DAHP, vascular response to Ach (10 μM; 1 mL/5 min) was obtained after application of AA (2.6 mM; 10 mL/1 min) plus 6R-BH4 (0.1 mM; 1 mL/5 min for 10 min). Moreover, the arterial ROS content was also detected using DHR-fluorescent probe (dihydrorhodamine 123 Sigma Chemical Co., USA) (10 μmole/L) as well. The experimental protocol of each group was shown in Figure 1.

Bottom Line: On 12th week after STZ injection, the findings showed that in DM group, Ach (10(-5) M)-induced vasodilatation was decreased, while the number of leukocyte adhesion was increased significantly (P < 0.01).By using dihydrorhodamine 123, our findings also indicated that the existing of ROS productions on diabetic arteriolar and venular walls were different significantly (ROS(arteriole) = 165.89 ± 24.59 and ROS(venule) = 172.26 ± 34.70) (P < 0.05).Moreover by using BH4 inhibitor to induce increase in arteriolar ROS, the results also confirmed that AA could improve endothelial function with closed correlation to its potential to reduce vascular ROS content.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand.

ABSTRACT
The correlation between endothelial function and reactive oxygen species detecting from diabetic microvascular wall and the antioxidant effect of ascorbic acid (AA) during early and late phases of diabetic induction were determined. Male Spraque-Dawley rats were divided into four groups: control, diabetes rats (DM, using iv.injection of 55 mg/kg BW streptozotocin, (STZ)), and two groups of DM rats treated with AA (1 g/L, (STZ)) starting on day 2 (DM + AAday2) and week 6th (DM + AA6wk). On 12th week after STZ injection, the findings showed that in DM group, Ach (10(-5) M)-induced vasodilatation was decreased, while the number of leukocyte adhesion was increased significantly (P < 0.01). Interestingly, these abnormalities induced by DM could be protected or improved in both AA-treated groups, DM + AAday2 and DM + AA6wk. By using dihydrorhodamine 123, our findings also indicated that the existing of ROS productions on diabetic arteriolar and venular walls were different significantly (ROS(arteriole) = 165.89 ± 24.59 and ROS(venule) = 172.26 ± 34.70) (P < 0.05). Moreover by using BH4 inhibitor to induce increase in arteriolar ROS, the results also confirmed that AA could improve endothelial function with closed correlation to its potential to reduce vascular ROS content.

No MeSH data available.


Related in: MedlinePlus