Abnormal retinal function and vasculature in mouse neonates with hyperglycemic mother after oxygen-induced retinopathy

Abstract

Purpose : Recent studies showed that diabetic mothers have a higher risk of delivering babies preterm, which may lead to retinopathy of prematurity in their babies. The association between maternal diabetes and retinopathy of prematurity is still unclear. To investigate the pathological changes in the retina of neonates with hyperglycemic mothers after oxygen-induced retinopathy (OIR), mouse pups generated by Ins2^Akita/+ female mothers were used.

Methods : Hyperglycemic heterozygous Ins2^Akita/+ mouse mothers and their neonates were first placed in an oxygen-controlled chamber with 75% oxygen from postnatal day (P)7 to P12. They were then returned to normal room air environment (RA) with 21% oxygen after P12. Mouse retinal function on P17, P21 and P30 was measured using electroretinography (ERG). To assess for changes in the retinal vasculature, retinal whole mounts were collected on P7, P12, P17, P21, and P30. The retinal blood vessels were visualized by immunohistochemistry using isolectin B4.

Results : Neuroretinal function was investigated using scotopic ERG. Normal retinal function was observed from P17 to P30 under room air condition. However, both a- wave and b- wave amplitudes decreased significantly after OIR on P17, P21 and P30 (p<0.05). To examine the retinal vasculature development in OIR pups under the care of hyperglycemic mother, immunoreactivity for isolectin GS-IB4 in retinal whole mounts was analyzed. The retinal vasculature of RA group developed normally from P12, P17, P21, to P30 with no obvious abnormalities. However, the retinae after OIR showed distinct abnormalities. Avascular area with minimal isolectin B4 immunoreactivity was observed on P12, P17 and P21 with slower revascularization. Yet, almost complete revascularization was detected on P30.

Conclusions : Retinal function and vascular development of pups were not affected by maternal hyperglycemia under room air condition. However, abnormal neuroretinal function and retinal vasculature were obvious after OIR.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.