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Aerobic Exercise Training Prevents the Onset of Endothelial Dysfunction via Increased Nitric Oxide Bioavailability and Reduced Reactive Oxygen Species in an Experimental Model of Menopause.

Braga VA, Couto GK, Lazzarin MC, Rossoni LV, Medeiros A - PLoS ONE (2015)

Bottom Line: Training prevented this response in OVX-TRA (Rmax: OVX-TRA: 88±2.0%, p<0.01), while did not change it in SHAM-TRA (Rmax: SHAM-TRA: 80±2.2%, p<0.01).The L-NAME incubation abolished the differences in ACh-induced relaxation among groups.OVX reduced nitrite/nitrate plasma concentrations and increased ROS in aortic slices, training as effective to restore these parameters to the SHAM levels.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, Federal University of Sao Paulo, Santos, Sao Paulo, Brazil.

ABSTRACT

Objective: Previous studies have shown that estrogen deficiency, arising in postmenopause, promotes endothelial dysfunction. This study evaluated the effects of aerobic exercise training on endothelial dependent vasodilation of aorta in ovariectomized rats, specifically investigating the role of nitric oxide (NO) and reactive oxygen species (ROS).

Methods: Female Wistar rats ovariectomized (OVX - n=20) or with intact ovary (SHAM - n=20) remained sedentary (OVX and SHAM) or performed aerobic exercise training on a treadmill 5 times a week for a period of 8 weeks (OVX-TRA and SHAM-TRA). In the thoracic aorta the endothelium-dependent and -independent vasodilation was assessed by acetylcholine (ACh) and sodium nitroprusside (SNP), respectively. Certain aortic rings were incubated with L-NAME to assess the NO modulation on the ACh-induced vasodilation. The fluorescence to dihydroethidium in aortic slices and plasma nitrite/nitrate concentrations were measured to evaluate ROS and NO bioavailability, respectively.

Results: ACh-induced vasodilation was reduced in OVX rats as compared SHAM (Rmax: SHAM: 86±3.3 vs. OVX: 57±3.0%, p<0.01). Training prevented this response in OVX-TRA (Rmax: OVX-TRA: 88±2.0%, p<0.01), while did not change it in SHAM-TRA (Rmax: SHAM-TRA: 80±2.2%, p<0.01). The L-NAME incubation abolished the differences in ACh-induced relaxation among groups. SNP-induced vasodilation was not different among groups. OVX reduced nitrite/nitrate plasma concentrations and increased ROS in aortic slices, training as effective to restore these parameters to the SHAM levels.

Conclusions: Exercise training, even in estrogen deficiency conditions, is able to improve endothelial dependent vasodilation in rat aorta via enhanced NO bioavailability and reduced ROS levels.

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Related in: MedlinePlus

Concentration—response curve to acetylcholine (A) and sodium nitroprusside (B) in aortic rings from SHAM, SHAM-TRA, OVX and OVX-TRA.The numbers shown in the legend represent the number of animals analyzed in each group. Results are expressed as means±SEM. Two-way ANOVA: *p<0.01 in comparison to SHAM, # p<0.01 in comparison to OVX.
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pone.0125388.g001: Concentration—response curve to acetylcholine (A) and sodium nitroprusside (B) in aortic rings from SHAM, SHAM-TRA, OVX and OVX-TRA.The numbers shown in the legend represent the number of animals analyzed in each group. Results are expressed as means±SEM. Two-way ANOVA: *p<0.01 in comparison to SHAM, # p<0.01 in comparison to OVX.

Mentions: The NE-induced (10-6 M) pre-contraction tonus was similar in all groups. The endothelium-dependent vasodilation induced by ACh was reduced in OVX aortas as compared to SHAM (Fig 1A) (Rmax: SHAM: 86±3.3 vs. OVX: 57±3.0%, p<0.01). Aerobic exercise training improved vasodilation induced by ACh in aorta from OVX-TRA rats as compared to SHAM-TRA rats (Fig 1A) (Rmax: SHAM-TRA: 80±2.2% vs. OVX-TRA: 88±2.0%, p<0.01), while it did not change the ACh-induced relaxation in aorta from SHAM-TRA as compared to SHAM (Fig 1A). However, no significant change in the vasodilator response induced by SNP was observed among groups (Fig 1B).


Aerobic Exercise Training Prevents the Onset of Endothelial Dysfunction via Increased Nitric Oxide Bioavailability and Reduced Reactive Oxygen Species in an Experimental Model of Menopause.

Braga VA, Couto GK, Lazzarin MC, Rossoni LV, Medeiros A - PLoS ONE (2015)

Concentration—response curve to acetylcholine (A) and sodium nitroprusside (B) in aortic rings from SHAM, SHAM-TRA, OVX and OVX-TRA.The numbers shown in the legend represent the number of animals analyzed in each group. Results are expressed as means±SEM. Two-way ANOVA: *p<0.01 in comparison to SHAM, # p<0.01 in comparison to OVX.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4414603&req=5

pone.0125388.g001: Concentration—response curve to acetylcholine (A) and sodium nitroprusside (B) in aortic rings from SHAM, SHAM-TRA, OVX and OVX-TRA.The numbers shown in the legend represent the number of animals analyzed in each group. Results are expressed as means±SEM. Two-way ANOVA: *p<0.01 in comparison to SHAM, # p<0.01 in comparison to OVX.
Mentions: The NE-induced (10-6 M) pre-contraction tonus was similar in all groups. The endothelium-dependent vasodilation induced by ACh was reduced in OVX aortas as compared to SHAM (Fig 1A) (Rmax: SHAM: 86±3.3 vs. OVX: 57±3.0%, p<0.01). Aerobic exercise training improved vasodilation induced by ACh in aorta from OVX-TRA rats as compared to SHAM-TRA rats (Fig 1A) (Rmax: SHAM-TRA: 80±2.2% vs. OVX-TRA: 88±2.0%, p<0.01), while it did not change the ACh-induced relaxation in aorta from SHAM-TRA as compared to SHAM (Fig 1A). However, no significant change in the vasodilator response induced by SNP was observed among groups (Fig 1B).

Bottom Line: Training prevented this response in OVX-TRA (Rmax: OVX-TRA: 88±2.0%, p<0.01), while did not change it in SHAM-TRA (Rmax: SHAM-TRA: 80±2.2%, p<0.01).The L-NAME incubation abolished the differences in ACh-induced relaxation among groups.OVX reduced nitrite/nitrate plasma concentrations and increased ROS in aortic slices, training as effective to restore these parameters to the SHAM levels.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, Federal University of Sao Paulo, Santos, Sao Paulo, Brazil.

ABSTRACT

Objective: Previous studies have shown that estrogen deficiency, arising in postmenopause, promotes endothelial dysfunction. This study evaluated the effects of aerobic exercise training on endothelial dependent vasodilation of aorta in ovariectomized rats, specifically investigating the role of nitric oxide (NO) and reactive oxygen species (ROS).

Methods: Female Wistar rats ovariectomized (OVX - n=20) or with intact ovary (SHAM - n=20) remained sedentary (OVX and SHAM) or performed aerobic exercise training on a treadmill 5 times a week for a period of 8 weeks (OVX-TRA and SHAM-TRA). In the thoracic aorta the endothelium-dependent and -independent vasodilation was assessed by acetylcholine (ACh) and sodium nitroprusside (SNP), respectively. Certain aortic rings were incubated with L-NAME to assess the NO modulation on the ACh-induced vasodilation. The fluorescence to dihydroethidium in aortic slices and plasma nitrite/nitrate concentrations were measured to evaluate ROS and NO bioavailability, respectively.

Results: ACh-induced vasodilation was reduced in OVX rats as compared SHAM (Rmax: SHAM: 86±3.3 vs. OVX: 57±3.0%, p<0.01). Training prevented this response in OVX-TRA (Rmax: OVX-TRA: 88±2.0%, p<0.01), while did not change it in SHAM-TRA (Rmax: SHAM-TRA: 80±2.2%, p<0.01). The L-NAME incubation abolished the differences in ACh-induced relaxation among groups. SNP-induced vasodilation was not different among groups. OVX reduced nitrite/nitrate plasma concentrations and increased ROS in aortic slices, training as effective to restore these parameters to the SHAM levels.

Conclusions: Exercise training, even in estrogen deficiency conditions, is able to improve endothelial dependent vasodilation in rat aorta via enhanced NO bioavailability and reduced ROS levels.

Show MeSH
Related in: MedlinePlus