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In vivo experiments reveal the good, the bad and the ugly faces of sFlt-1 in pregnancy.

Szalai G, Xu Y, Romero R, Chaiworapongsa T, Xu Z, Chiang PJ, Ahn H, Sundell B, Plazyo O, Jiang Y, Olive M, Wang B, Jacques SM, Qureshi F, Tarca AL, Erez O, Dong Z, Papp Z, Hassan SS, Hernandez-Andrade E, Than NG - PLoS ONE (2014)

Bottom Line: Truncated msFlt-1(1-3) simulated the preeclampsia-promoting effects of full-length hsFlt-1.MsFlt-1(1-3) had strong effect on maternal endothelium but not on placentas and embryos.In accord with the predominant placental expression of hsFlt-1-e15a and msFlt-1-i13, full-length sFlt-1 may have a role in the regulation of embryonic development.

View Article: PubMed Central - PubMed

Affiliation: Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, and Detroit, MI, United States of America.

ABSTRACT

Objective: Soluble fms-like tyrosine kinase (sFlt)-1-e15a, a primate-specific sFlt-1-isoform most abundant in the human placenta in preeclampsia, can induce preeclampsia in mice. This study compared the effects of full-length human (h)sFlt-1-e15a with those of truncated mouse (m)sFlt-1(1-3) used in previous preeclampsia studies on pregnancy outcome and clinical symptoms in preeclampsia.

Methods: Mice were injected with adenoviruses or fiber-mutant adenoviruses overexpressing hsFlt-1-e15a, msFlt-1(1-3) or control GFP under the CMV or CYP19A1 promoters on gestational day 8 (GD8) and GD11. Placentas and pups were delivered by cesarean section, and dams were monitored postpartum. Blood pressure was telemetrically recorded. Urine samples were collected with cystocentesis and examined for albumin/creatinine ratios. Tissue specimens were evaluated for transgene as well as endogenous mFlt-1 and msFlt-1-i13 expression. H&E-, Jones- and PAS-stained kidney sections were histopathologically examined. Placental GFP expression and aortic ring assays were investigated with confocal microscopy.

Results: Mean arterial blood pressure (MAP) was elevated before delivery in hsFlt-1-e15a-treated mice compared to controls (GD18: ΔMAP = 7.8 mmHg, p = 0.009), while ΔMAP was 12.8 mmHg (GD18, p = 0.005) in msFlt-1(1-3)-treated mice. Urine albumin/creatinine ratio was higher in hsFlt-1-e15a-treated mice than in controls (GD18, p = 0.04; PPD8, p = 0.03), and msFlt-1(1-3)-treated mice had marked proteinuria postpartum (PPD8, p = 4 × 10(-5)). Focal glomerular changes were detected in hsFlt-1-e15a and msFlt-1(1-3)-treated mice. Aortic ring microvessel outgrowth was decreased in hsFlt-1-e15a (p = 0.007) and msFlt-1(1-3)-treated (p = 0.02) mice. Full-length msFlt-1-i13 expression was unique for the placenta. In hsFlt-1-e15a-treated mice, the number of pups (p = 0.046), total weight of living pups (p = 0.04) and maternal weights (p = 0.04) were higher than in controls. These differences were not observed in truncated msFlt-1(1-3)-treated mice.

Conclusions: Truncated msFlt-1(1-3) simulated the preeclampsia-promoting effects of full-length hsFlt-1. MsFlt-1(1-3) had strong effect on maternal endothelium but not on placentas and embryos. In contrast, hsFlt-1-e15a induced preeclampsia-like symptoms; however, it also increased litter size. In accord with the predominant placental expression of hsFlt-1-e15a and msFlt-1-i13, full-length sFlt-1 may have a role in the regulation of embryonic development. These observations point to the difference in the biological effects of full-length and truncated sFlt-1 and the changes in the effect of full-length sFlt-1 during pregnancy, and may have important implications in the management of preeclampsia.

No MeSH data available.


Related in: MedlinePlus

Profiling of hsFlt-1-e15a and GFP expression.(A) Boxplots show the expression profile of the transgenic hsFlt-1-e15a mRNA overexpressed by three different adenoviral vectors (Ad-CMV-hsFlt-1-e15a; Ad-RGD-CMV-hsFlt-1-e15a; Ad-RGD-CYP-hsFlt-1-e15a) in placentas harvested on gestational day (GD) 18 and in tissues harvested on postpartum day (PPD) 8. (B) Boxplots show the expression profile of GFP mRNA overexpressed by two different vectors (Ad-RGD-CMV-GFP; Ad-RGD-CYP-GFP) in placentas harvested on GD18 and in tissues harvested on PPD8. (C) Control placenta, H&E staining, 20x magnification. (D) Control placenta, anti-CD31 immunostaining, 20x magnification. The CD31 immunopositivity of the labyrinthine vessels are clearly seen. (E, F) Confocal microscopic images of placentas from GFP-treated mice. The placental expression of adenoviral GFP was the strongest in the labyrinth in both the Ad-RGD-CMV-GFP and Ad-RGD-CYP-GFP treated groups.
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pone-0110867-g004: Profiling of hsFlt-1-e15a and GFP expression.(A) Boxplots show the expression profile of the transgenic hsFlt-1-e15a mRNA overexpressed by three different adenoviral vectors (Ad-CMV-hsFlt-1-e15a; Ad-RGD-CMV-hsFlt-1-e15a; Ad-RGD-CYP-hsFlt-1-e15a) in placentas harvested on gestational day (GD) 18 and in tissues harvested on postpartum day (PPD) 8. (B) Boxplots show the expression profile of GFP mRNA overexpressed by two different vectors (Ad-RGD-CMV-GFP; Ad-RGD-CYP-GFP) in placentas harvested on GD18 and in tissues harvested on PPD8. (C) Control placenta, H&E staining, 20x magnification. (D) Control placenta, anti-CD31 immunostaining, 20x magnification. The CD31 immunopositivity of the labyrinthine vessels are clearly seen. (E, F) Confocal microscopic images of placentas from GFP-treated mice. The placental expression of adenoviral GFP was the strongest in the labyrinth in both the Ad-RGD-CMV-GFP and Ad-RGD-CYP-GFP treated groups.

Mentions: To compare the expression patterns of hsFlt-1-e15a and GFP, total RNAs were isolated from tissue samples harvested from virus-infected mice. Human hsFlt-1-e15a and GFP mRNA expression varied according to the viral constructs (adenovirus or fiber-mutant adenovirus) and promoters (CMV or CYP). The fiber-mutant adenovirus supported a higher hsFlt-1-e15a mRNA expression in the kidney and liver compared to the adenovirus, while the CYP promoter restricted hsFlt-1-e15a mRNA expression in the liver compared to the CMV promoter (Figure 4A). Similarly, the CYP promoter restricted GFP mRNA expression in the liver (49.8-fold down-regulation, p = 0.005), kidney (9.3-fold down-regulation, p = 0.02) and spleen (13.5-fold down-regulation, p = 0.01) compared to the CMV promoter, leading to the highest GFP mRNA expression in the placenta (Figure 4B). GFP expression was mainly restricted to the labyrinth zone of the placenta irrespective of the promoter in RGD fiber-mutant virus injected mice (Figure 4C–E).


In vivo experiments reveal the good, the bad and the ugly faces of sFlt-1 in pregnancy.

Szalai G, Xu Y, Romero R, Chaiworapongsa T, Xu Z, Chiang PJ, Ahn H, Sundell B, Plazyo O, Jiang Y, Olive M, Wang B, Jacques SM, Qureshi F, Tarca AL, Erez O, Dong Z, Papp Z, Hassan SS, Hernandez-Andrade E, Than NG - PLoS ONE (2014)

Profiling of hsFlt-1-e15a and GFP expression.(A) Boxplots show the expression profile of the transgenic hsFlt-1-e15a mRNA overexpressed by three different adenoviral vectors (Ad-CMV-hsFlt-1-e15a; Ad-RGD-CMV-hsFlt-1-e15a; Ad-RGD-CYP-hsFlt-1-e15a) in placentas harvested on gestational day (GD) 18 and in tissues harvested on postpartum day (PPD) 8. (B) Boxplots show the expression profile of GFP mRNA overexpressed by two different vectors (Ad-RGD-CMV-GFP; Ad-RGD-CYP-GFP) in placentas harvested on GD18 and in tissues harvested on PPD8. (C) Control placenta, H&E staining, 20x magnification. (D) Control placenta, anti-CD31 immunostaining, 20x magnification. The CD31 immunopositivity of the labyrinthine vessels are clearly seen. (E, F) Confocal microscopic images of placentas from GFP-treated mice. The placental expression of adenoviral GFP was the strongest in the labyrinth in both the Ad-RGD-CMV-GFP and Ad-RGD-CYP-GFP treated groups.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4230935&req=5

pone-0110867-g004: Profiling of hsFlt-1-e15a and GFP expression.(A) Boxplots show the expression profile of the transgenic hsFlt-1-e15a mRNA overexpressed by three different adenoviral vectors (Ad-CMV-hsFlt-1-e15a; Ad-RGD-CMV-hsFlt-1-e15a; Ad-RGD-CYP-hsFlt-1-e15a) in placentas harvested on gestational day (GD) 18 and in tissues harvested on postpartum day (PPD) 8. (B) Boxplots show the expression profile of GFP mRNA overexpressed by two different vectors (Ad-RGD-CMV-GFP; Ad-RGD-CYP-GFP) in placentas harvested on GD18 and in tissues harvested on PPD8. (C) Control placenta, H&E staining, 20x magnification. (D) Control placenta, anti-CD31 immunostaining, 20x magnification. The CD31 immunopositivity of the labyrinthine vessels are clearly seen. (E, F) Confocal microscopic images of placentas from GFP-treated mice. The placental expression of adenoviral GFP was the strongest in the labyrinth in both the Ad-RGD-CMV-GFP and Ad-RGD-CYP-GFP treated groups.
Mentions: To compare the expression patterns of hsFlt-1-e15a and GFP, total RNAs were isolated from tissue samples harvested from virus-infected mice. Human hsFlt-1-e15a and GFP mRNA expression varied according to the viral constructs (adenovirus or fiber-mutant adenovirus) and promoters (CMV or CYP). The fiber-mutant adenovirus supported a higher hsFlt-1-e15a mRNA expression in the kidney and liver compared to the adenovirus, while the CYP promoter restricted hsFlt-1-e15a mRNA expression in the liver compared to the CMV promoter (Figure 4A). Similarly, the CYP promoter restricted GFP mRNA expression in the liver (49.8-fold down-regulation, p = 0.005), kidney (9.3-fold down-regulation, p = 0.02) and spleen (13.5-fold down-regulation, p = 0.01) compared to the CMV promoter, leading to the highest GFP mRNA expression in the placenta (Figure 4B). GFP expression was mainly restricted to the labyrinth zone of the placenta irrespective of the promoter in RGD fiber-mutant virus injected mice (Figure 4C–E).

Bottom Line: Truncated msFlt-1(1-3) simulated the preeclampsia-promoting effects of full-length hsFlt-1.MsFlt-1(1-3) had strong effect on maternal endothelium but not on placentas and embryos.In accord with the predominant placental expression of hsFlt-1-e15a and msFlt-1-i13, full-length sFlt-1 may have a role in the regulation of embryonic development.

View Article: PubMed Central - PubMed

Affiliation: Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, and Detroit, MI, United States of America.

ABSTRACT

Objective: Soluble fms-like tyrosine kinase (sFlt)-1-e15a, a primate-specific sFlt-1-isoform most abundant in the human placenta in preeclampsia, can induce preeclampsia in mice. This study compared the effects of full-length human (h)sFlt-1-e15a with those of truncated mouse (m)sFlt-1(1-3) used in previous preeclampsia studies on pregnancy outcome and clinical symptoms in preeclampsia.

Methods: Mice were injected with adenoviruses or fiber-mutant adenoviruses overexpressing hsFlt-1-e15a, msFlt-1(1-3) or control GFP under the CMV or CYP19A1 promoters on gestational day 8 (GD8) and GD11. Placentas and pups were delivered by cesarean section, and dams were monitored postpartum. Blood pressure was telemetrically recorded. Urine samples were collected with cystocentesis and examined for albumin/creatinine ratios. Tissue specimens were evaluated for transgene as well as endogenous mFlt-1 and msFlt-1-i13 expression. H&E-, Jones- and PAS-stained kidney sections were histopathologically examined. Placental GFP expression and aortic ring assays were investigated with confocal microscopy.

Results: Mean arterial blood pressure (MAP) was elevated before delivery in hsFlt-1-e15a-treated mice compared to controls (GD18: ΔMAP = 7.8 mmHg, p = 0.009), while ΔMAP was 12.8 mmHg (GD18, p = 0.005) in msFlt-1(1-3)-treated mice. Urine albumin/creatinine ratio was higher in hsFlt-1-e15a-treated mice than in controls (GD18, p = 0.04; PPD8, p = 0.03), and msFlt-1(1-3)-treated mice had marked proteinuria postpartum (PPD8, p = 4 × 10(-5)). Focal glomerular changes were detected in hsFlt-1-e15a and msFlt-1(1-3)-treated mice. Aortic ring microvessel outgrowth was decreased in hsFlt-1-e15a (p = 0.007) and msFlt-1(1-3)-treated (p = 0.02) mice. Full-length msFlt-1-i13 expression was unique for the placenta. In hsFlt-1-e15a-treated mice, the number of pups (p = 0.046), total weight of living pups (p = 0.04) and maternal weights (p = 0.04) were higher than in controls. These differences were not observed in truncated msFlt-1(1-3)-treated mice.

Conclusions: Truncated msFlt-1(1-3) simulated the preeclampsia-promoting effects of full-length hsFlt-1. MsFlt-1(1-3) had strong effect on maternal endothelium but not on placentas and embryos. In contrast, hsFlt-1-e15a induced preeclampsia-like symptoms; however, it also increased litter size. In accord with the predominant placental expression of hsFlt-1-e15a and msFlt-1-i13, full-length sFlt-1 may have a role in the regulation of embryonic development. These observations point to the difference in the biological effects of full-length and truncated sFlt-1 and the changes in the effect of full-length sFlt-1 during pregnancy, and may have important implications in the management of preeclampsia.

No MeSH data available.


Related in: MedlinePlus