Limits...
Placental growth factor contributes to micro-vascular abnormalization and blood-retinal barrier breakdown in diabetic retinopathy.

Kowalczuk L, Touchard E, Omri S, Jonet L, Klein C, Valamanes F, Berdugo M, Bigey P, Massin P, Jeanny JC, Behar-Cohen F - PLoS ONE (2011)

Bottom Line: For a better understanding of its role on the retina, we have evaluated the effect of a sustained PGF over-expression in rat ocular media, using ciliary muscle electrotransfer (ET) of a plasmid encoding rat PGF-1 (pVAX2-rPGF-1). pVAX2-rPGF-1 ET in the ciliary muscle (200 V/cm) was achieved in non diabetic and diabetic rat eyes.After the control of rPGF-1 expression, PGF-induced effects on retinal vasculature and on the blood-external barrier were evaluated respectively by lectin and occludin staining on flat-mounts.PGF and its receptor Flt-1 may therefore be looked upon as a potential regulatory target at this stage of the disease.

View Article: PubMed Central - PubMed

Affiliation: Institut National pour la Santé Et la Recherche Médicale U872, Physiopathology of ocular diseases: Therapeutic innovations, Paris, France.

ABSTRACT

Objective: There are controversies regarding the pro-angiogenic activity of placental growth factor (PGF) in diabetic retinopathy (DR). For a better understanding of its role on the retina, we have evaluated the effect of a sustained PGF over-expression in rat ocular media, using ciliary muscle electrotransfer (ET) of a plasmid encoding rat PGF-1 (pVAX2-rPGF-1).

Materials and methods: pVAX2-rPGF-1 ET in the ciliary muscle (200 V/cm) was achieved in non diabetic and diabetic rat eyes. Control eyes received saline or naked plasmid ET. Clinical follow up was carried out over three months using slit lamp examination and fluorescein angiography. After the control of rPGF-1 expression, PGF-induced effects on retinal vasculature and on the blood-external barrier were evaluated respectively by lectin and occludin staining on flat-mounts. Ocular structures were visualized through histological analysis.

Results: After fifteen days of rPGF-1 over-expression in normal eyes, tortuous and dilated capillaries were observed. At one month, microaneurysms and moderate vascular sprouts were detected in mid retinal periphery in vivo and on retinal flat-mounts. At later stages, retinal pigmented epithelial cells demonstrated morphological abnormalities and junction ruptures. In diabetic retinas, PGF expression rose between 2 and 5 months, and, one month after ET, rPGF-1 over-expression induced glial activation and proliferation.

Conclusion: This is the first demonstration that sustained intraocular PGF production induces vascular and retinal changes similar to those observed in the early stages of diabetic retinopathy. PGF and its receptor Flt-1 may therefore be looked upon as a potential regulatory target at this stage of the disease.

Show MeSH

Related in: MedlinePlus

Analysis of flat-mounted diabetic retinas labeled with FITC-conjugated lectin from Bandeira simplicifolia, one month after ET.(a) Quantitative analysis of the retinal vasculature from control and PGF ET-treated diabetic rat eyes. (b) Microscopy of flat-mounted control (b1, b3) and PGF ET-treated (b2, b4) diabetic retinas. (b1–b2) Optic microscopy on mosaics made with microscopic images at low magnification (x4) showing no evident difference of the retinal vascularization between control (b1) and pVAX-2-rPGF-1 ET-treated eyes (b2), except a weak retinal venous dilation in treated retinas (between arrowheads). (b3, b4) Confocal microscopy showing lectin-labeled cell infiltration (arrow) and micro-aneurysmal-like structures observed in both group (insets).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3049767&req=5

pone-0017462-g007: Analysis of flat-mounted diabetic retinas labeled with FITC-conjugated lectin from Bandeira simplicifolia, one month after ET.(a) Quantitative analysis of the retinal vasculature from control and PGF ET-treated diabetic rat eyes. (b) Microscopy of flat-mounted control (b1, b3) and PGF ET-treated (b2, b4) diabetic retinas. (b1–b2) Optic microscopy on mosaics made with microscopic images at low magnification (x4) showing no evident difference of the retinal vascularization between control (b1) and pVAX-2-rPGF-1 ET-treated eyes (b2), except a weak retinal venous dilation in treated retinas (between arrowheads). (b3, b4) Confocal microscopy showing lectin-labeled cell infiltration (arrow) and micro-aneurysmal-like structures observed in both group (insets).

Mentions: In addition, analysis of the lectin-labeled flat-mounts, retinas from 5 months-old GK eyes demonstrated some vascular abnormalities. In normal GK retinas, vascularized area was higher (27.2%±0.03%) than in normal non diabetic retinas (18.8%±0.02%, p<0.0001%), and vessels appeared tortuous with some vascular irregularities (Fig. 7b1–b3).


Placental growth factor contributes to micro-vascular abnormalization and blood-retinal barrier breakdown in diabetic retinopathy.

Kowalczuk L, Touchard E, Omri S, Jonet L, Klein C, Valamanes F, Berdugo M, Bigey P, Massin P, Jeanny JC, Behar-Cohen F - PLoS ONE (2011)

Analysis of flat-mounted diabetic retinas labeled with FITC-conjugated lectin from Bandeira simplicifolia, one month after ET.(a) Quantitative analysis of the retinal vasculature from control and PGF ET-treated diabetic rat eyes. (b) Microscopy of flat-mounted control (b1, b3) and PGF ET-treated (b2, b4) diabetic retinas. (b1–b2) Optic microscopy on mosaics made with microscopic images at low magnification (x4) showing no evident difference of the retinal vascularization between control (b1) and pVAX-2-rPGF-1 ET-treated eyes (b2), except a weak retinal venous dilation in treated retinas (between arrowheads). (b3, b4) Confocal microscopy showing lectin-labeled cell infiltration (arrow) and micro-aneurysmal-like structures observed in both group (insets).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3049767&req=5

pone-0017462-g007: Analysis of flat-mounted diabetic retinas labeled with FITC-conjugated lectin from Bandeira simplicifolia, one month after ET.(a) Quantitative analysis of the retinal vasculature from control and PGF ET-treated diabetic rat eyes. (b) Microscopy of flat-mounted control (b1, b3) and PGF ET-treated (b2, b4) diabetic retinas. (b1–b2) Optic microscopy on mosaics made with microscopic images at low magnification (x4) showing no evident difference of the retinal vascularization between control (b1) and pVAX-2-rPGF-1 ET-treated eyes (b2), except a weak retinal venous dilation in treated retinas (between arrowheads). (b3, b4) Confocal microscopy showing lectin-labeled cell infiltration (arrow) and micro-aneurysmal-like structures observed in both group (insets).
Mentions: In addition, analysis of the lectin-labeled flat-mounts, retinas from 5 months-old GK eyes demonstrated some vascular abnormalities. In normal GK retinas, vascularized area was higher (27.2%±0.03%) than in normal non diabetic retinas (18.8%±0.02%, p<0.0001%), and vessels appeared tortuous with some vascular irregularities (Fig. 7b1–b3).

Bottom Line: For a better understanding of its role on the retina, we have evaluated the effect of a sustained PGF over-expression in rat ocular media, using ciliary muscle electrotransfer (ET) of a plasmid encoding rat PGF-1 (pVAX2-rPGF-1). pVAX2-rPGF-1 ET in the ciliary muscle (200 V/cm) was achieved in non diabetic and diabetic rat eyes.After the control of rPGF-1 expression, PGF-induced effects on retinal vasculature and on the blood-external barrier were evaluated respectively by lectin and occludin staining on flat-mounts.PGF and its receptor Flt-1 may therefore be looked upon as a potential regulatory target at this stage of the disease.

View Article: PubMed Central - PubMed

Affiliation: Institut National pour la Santé Et la Recherche Médicale U872, Physiopathology of ocular diseases: Therapeutic innovations, Paris, France.

ABSTRACT

Objective: There are controversies regarding the pro-angiogenic activity of placental growth factor (PGF) in diabetic retinopathy (DR). For a better understanding of its role on the retina, we have evaluated the effect of a sustained PGF over-expression in rat ocular media, using ciliary muscle electrotransfer (ET) of a plasmid encoding rat PGF-1 (pVAX2-rPGF-1).

Materials and methods: pVAX2-rPGF-1 ET in the ciliary muscle (200 V/cm) was achieved in non diabetic and diabetic rat eyes. Control eyes received saline or naked plasmid ET. Clinical follow up was carried out over three months using slit lamp examination and fluorescein angiography. After the control of rPGF-1 expression, PGF-induced effects on retinal vasculature and on the blood-external barrier were evaluated respectively by lectin and occludin staining on flat-mounts. Ocular structures were visualized through histological analysis.

Results: After fifteen days of rPGF-1 over-expression in normal eyes, tortuous and dilated capillaries were observed. At one month, microaneurysms and moderate vascular sprouts were detected in mid retinal periphery in vivo and on retinal flat-mounts. At later stages, retinal pigmented epithelial cells demonstrated morphological abnormalities and junction ruptures. In diabetic retinas, PGF expression rose between 2 and 5 months, and, one month after ET, rPGF-1 over-expression induced glial activation and proliferation.

Conclusion: This is the first demonstration that sustained intraocular PGF production induces vascular and retinal changes similar to those observed in the early stages of diabetic retinopathy. PGF and its receptor Flt-1 may therefore be looked upon as a potential regulatory target at this stage of the disease.

Show MeSH
Related in: MedlinePlus