Effect of Tempol on Diabetes-Induced Decreases in Retinal Blood Flow in the Mouse

Yadav, Amit Singh

doi:10.3109/02713683.2011.556300

Cited by 22 publications

(26 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They are also similar to other reported reductions in F values in STZ-diabetic mice. 32–36 Had these investigators measured O 2A , it is likely that they would have found decreases in DO 2 similar to the decrease of 43% in the current study. These defective DO 2 and F responses in diabetes likely correspond to the well-known impaired autoregulation seen in humans with diabetes.…”

Section: Discussionsupporting

confidence: 57%

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice

Blair

Wanek

Felder

et al. 2016

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

PurposeRetinal nonperfusion and hypoxia are important factors in human diabetic retinopathy, and these presumably inhibit energy production and lead to cell death. The purpose of this study was to elucidate the effect of diabetes on inner retinal oxygen delivery and metabolism in a mouse model of diabetes.MethodsPhosphorescence lifetime and blood flow imaging were performed in spontaneously diabetic Ins2Akita (n = 22) and nondiabetic (n = 22) mice at 12 and 24 weeks of age to measure retinal arterial (O2A) and venous (O2V) oxygen contents and total retinal blood flow (F). Inner retinal oxygen delivery (DO2) and metabolism (MO2) were calculated as F ∗ O2A and F ∗ (O2A − O2V), respectively. Oxygen extraction fraction (OEF), which equals MO2/DO2, was calculated.ResultsDO2 at 12 weeks were 112 ± 40 and 97 ± 29 nL O2/min in nondiabetic and diabetic mice, respectively (NS), and 148 ± 31 and 85 ± 37 nL O2/min at 24 weeks, respectively (P < 0.001). MO2 were 65 ± 31 and 66 ± 27 nL O2/min in nondiabetic and diabetic mice at 12 weeks, respectively, and 79 ± 14 and 54 ± 28 nL O2/min at 24 weeks, respectively (main effects = NS). At 12 weeks OEF were 0.57 ± 0.17 and 0.67 ± 0.09 in nondiabetic and diabetic mice, respectively, and 0.54 ± 0.07 and 0.63 ± 0.08 at 24 weeks, respectively (main effect of diabetes: P < 0.01).ConclusionsInner retinal MO2 was maintained in diabetic Akita mice indicating that elevation of the OEF adequately compensated for reduced DO2 and prevented oxidative metabolism from being limited by hypoxia.

show abstract

Section: Discussionsupporting

confidence: 57%

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice

Blair

Wanek

Felder

et al. 2016

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

show abstract

“…Similar to early human DR, we observe significant decreases in retinal blood flow rates in the initial weeks of hyperglycemia in diabetic rats and mice (Lee and Harris 2008; Lee et al, 2008; Wright and Harris 2008; Wright et al, 2009; Wang et al, 2010; Wang et al, 2011; Yadav and Harris 2011). The magnitude of the decrease within the first several weeks of developing hyperglycemia in rodents is ~25-40%, very similar to the change seen in early human DR.…”

Section: Introductionsupporting

confidence: 63%

Retinal blood flow abnormalities following six months of hyperglycemia in the Ins2(Akita) mouse

Wright

Yadav

McElhatten

et al. 2012

Experimental Eye Research

Self Cite

View full text Add to dashboard Cite

The aim of this study was to characterize the microvascular flow abnormalities and oxygenation changes that are present following six months of hyperglycemia in the diabetic Ins2(Akita) mouse. Previous studies have shown decreased retinal blood flow in the first several weeks of hyperglycemia in rodents, similar to the decreases seen in the early stages of human diabetes. However, whether this alteration in the mouse retina continues beyond the initial weeks of diabetes has yet to be determined, as are the potential consequences of the decreased flow on retinal oxygenation. In this study, male Ins2(Akita) and age-matched C57BL/6 (non-diabetic) mice were maintained for a period of six months, at which time intravital microscopy was used to measure retinal blood vessel diameters, blood cell velocity, vascular wall shear rates, blood flow rates, and transient capillary occlusions. In addition, the presence of hypoxia was assessed using the oxygen-sensitive probe pimonidazole. The diabetic retinal microvasculature displayed decreases in red blood cell velocity (30%, p<0.001), shear rate (25%, p<0.01), and flow rate (40%, p<0.001). Moreover, transient capillary stoppages in flow were observed in the diabetic mice, but rarely in the non-diabetic mice. However, no alterations were observed in retinal hypoxia as determined by a pimonidazole assay, suggesting the possibility that the decreases seen in retinal blood flow may be dictated by a decrease in retinal oxygen utilization.

show abstract

“…In the larger vessels of the healthy retina, centerline velocity is approximately 30 mm ⁄ s (Nagaoka & Yoshida 2006;Nagaoka et al 2009;Yadav & Harris 2011). Fringe washout, the phenomenon responsible for the decrease in SD-OCT signal at high flow velocities, becomes significant at flow velocities above 34 mm ⁄ s when the direction of flow is <5 degrees away from the perpendicular to the line of sight (Hendargo et al 2011).…”

Section: Discussionmentioning

confidence: 99%

Retinal and choroidal intravascular spectral‐domain optical coherence tomography

Willerslev

Cordtz

et al. 2013

Acta Ophthalmologica

View full text Add to dashboard Cite

ABSTRACT.Purpose: To examine retinal and choroidal blood vessels using spectral-domain optical coherence tomography (SD-OCT). Methods: Retrospective case series. Results: Scans through retinal blood vessels in healthy subjects demonstrated vessel wall reflexes and a tri-layer profile of the blood column on longitudinal scans and a figure-of-eight configuration on cross-sectional scans. Intravascular reflectivity decreased with increasingly oblique angles of observation and was absent when blood flow was parallel to the line of sight. The high blood flow in the choroidal vessels in healthy subjects and the low flow in the retinal vessels in patients with ocular ischaemic syndrome and central retinal artery occlusion were both associated with lower reflectivity of the blood and an unstructured intravascular SD-OCT profile. Discussion: This qualitative in vivo study found a characteristically structured SD-OCT profile of the blood column in retinal vessels with normal blood flow. Both structure and total reflectivity faded when blood flow was lower or higher than normal or at oblique angles to the line of sight. In conclusion, SD-OCT scans of the vessels in the posterior pole of the eye may assist the clinical assessment of gross abnormalities of ocular blood flow, e.g. in carotid artery stenosis.Key words: blood flow imaging -central retinal artery occlusion -choroidal blood flow -in vivo -ocular ischemic syndrome -optical coherence tomography -red blood cell alignment -retinal blood flow -shear rate

show abstract

Effect of Tempol on Diabetes-Induced Decreases in Retinal Blood Flow in the Mouse

Abstract: The antioxidant tempol provides partial improvements in retinal microvascular hemodynamics early in the progression of STZ-induced diabetes in mice.

Cited by 22 publications

References 26 publications

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice

Retinal blood flow abnormalities following six months of hyperglycemia in the Ins2(Akita) mouse

Retinal and choroidal intravascular spectral‐domain optical coherence tomography

Contact Info

Product

Resources

About

Effect of Tempol on Diabetes-Induced Decreases in Retinal Blood Flow in the Mouse

Abstract: The antioxidant tempol provides partial improvements in retinal microvascular hemodynamics early in the progression of STZ-induced diabetes in mice.

Cited by 22 publications

References 26 publications

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2Akita Diabetic Mice

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2Akita Diabetic Mice

Retinal blood flow abnormalities following six months of hyperglycemia in the Ins2(Akita) mouse

Retinal and choroidal intravascular spectral‐domain optical coherence tomography

Contact Info

Product

Resources

About

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice

Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2^Akita Diabetic Mice