| 1. |
- Connor, K. M., et al.
(författare)
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Increased dietary intake of omega-3-polyunsaturated fatty acids reduces pathological retinal angiogenesis
- 2007
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Ingår i: Nat Med. - 1078-8956.
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Tidskriftsartikel (refereegranskat)abstract
- Many sight-threatening diseases have two critical phases, vessel loss followed by hypoxia-driven destructive neovascularization. These diseases include retinopathy of prematurity and diabetic retinopathy, leading causes of blindness in childhood and middle age affecting over 4 million people in the United States. We studied the influence of omega-3- and omega-6-polyunsaturated fatty acids (PUFAs) on vascular loss, vascular regrowth after injury, and hypoxia-induced pathological neovascularization in a mouse model of oxygen-induced retinopathy. We show that increasing omega-3-PUFA tissue levels by dietary or genetic means decreased the avascular area of the retina by increasing vessel regrowth after injury, thereby reducing the hypoxic stimulus for neovascularization. The bioactive omega-3-PUFA-derived mediators neuroprotectinD1, resolvinD1 and resolvinE1 also potently protected against neovascularization. The protective effect of omega-3-PUFAs and their bioactive metabolites was mediated, in part, through suppression of tumor necrosis factor-alpha. This inflammatory cytokine was found in a subset of microglia that was closely associated with retinal vessels. These findings indicate that increasing the sources of omega-3-PUFA or their bioactive products reduces pathological angiogenesis. Western diets are often deficient in omega-3-PUFA, and premature infants lack the important transfer from the mother to the infant of omega-3-PUFA that normally occurs in the third trimester of pregnancy. Supplementing omega-3-PUFA intake may be of benefit in preventing retinopathy.
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| 2. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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A pharmacokinetic and dosing study of intravenous insulin-like growth factor-I and IGF-binding protein-3 complex to preterm infants
- 2009
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Ingår i: Pediatric Research. - 1530-0447 .- 0031-3998. ; 65:5, s. 574-9
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Tidskriftsartikel (refereegranskat)abstract
- In preterm infants, low levels of insulin like growth factor 1 (IGF-I) have been associated with impaired growth and retinopathy of prematurity. Our objective was to study safety and pharmacokinetics of i.v. administered rhIGF-I with its binding protein 3 (rhIGFBP-3) to preterm infants. At 3 d chronological age, an i.v. 3 h infusion of rhIGF-I/rhIGFBP-3 was administered followed by serial measurements of IGF-I and IGFBP-3. Infants were evaluated for physiologic safety measurements. The individual dose of rhIGF-I ranged from 1 to 12 microg/kg. The study was conducted at Queen Silvia Children's Hospital, Gothenburg, Sweden, between January and November 2007. Five patients (3 F) with mean (range) post menstrual age 27 wk (26-29) and birth weight 1022 g (810-1310) participated. IGF-I and IGFBP-3 levels before infusion were median (range) 18 (12-28) and 771 (651-1047) ng/mL, respectively. Immediately after study drug infusion, serum IGF-I and IGFBP-3 levels were 38 (25-59) and 838 (754-1182) ng/mL, respectively. Median (range) half-life for IGF-I and IGFBP-3 was 0.79 (0.59-1.42) and 0.87 (0.85-0.94) hours, respectively. Blood glucose, insulin, sodium, potassium, and physiologic safety measures were within normal ranges. The rhIGF-I/rhIGFBP-3 equimolar proportion was effective in increasing serum IGF-I levels and administration under these study conditions was safe and well tolerated.
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| 3. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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IGFBP3 suppresses retinopathy through suppression of oxygen-induced vessel loss and promotion of vascular regrowth
- 2007
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Ingår i: Proc Natl Acad Sci U S A. - 0027-8424. ; 104:25, s. 10589-94
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Tidskriftsartikel (refereegranskat)abstract
- Vessel loss precipitates many diseases. In particular, vessel loss resulting in hypoxia induces retinal neovascularization in diabetic retinopathy and in retinopathy of prematurity (ROP), major causes of blindness. Here we define insulin-like growth factor binding protein-3 (IGFBP3) as a new modulator of vascular survival and regrowth in oxygen-induced retinopathy. In IGFBP3-deficient mice, there was a dose-dependent increase in oxygen-induced retinal vessel loss. Subsequent to oxygen-induced retinal vessel loss, Igfbp3(-/-) mice had a 31% decrease in retinal vessel regrowth versus controls after returning to room air. No difference in serum insulin-like growth factor 1 (IGF1) levels was observed among groups. Wild-type mice treated with exogenous IGFBP3 had a significant increase in vessel regrowth. This correlated with a 30% increase in endothelial progenitor cells in the retina at postnatal day 15, indicating that IGFBP3 could be serving as a progenitor cell chemoattractant. In a prospective clinical study, we measured IGFBP3 (and IGF1) plasma levels weekly and examined retinas in all premature infants born at gestational ages <32 weeks at high risk for ROP. The mean level of IGFBP3 at 30-35 weeks postmenstrual age (PMA) for infants with proliferative ROP (ROP stages 3>, n = 13) was 802 microg/liter, and for infants with no ROP (ROP stage 0, n = 38) the mean level was 974 microg/liter (P < 0.03). These results suggest that IGFBP3, acting independently of IGF1, helps to prevent oxygen-induced vessel loss and to promote vascular regrowth after vascular destruction in vivo in a dose-dependent manner, resulting in less retinal neovascularization.
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| 4. |
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| 5. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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Longitudinal Postnatal Weight and Insulin-like Growth Factor I Measurements in the Prediction of Retinopathy of Prematurity
- 2006
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Ingår i: Arch Ophthalmol. - : American Medical Association (AMA). ; 124:12, s. 1711-1718
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Tidskriftsartikel (refereegranskat)abstract
- Objective To investigate whether postnatal growth and development influence retinopathy of prematurity (ROP) and may be included in screening for ROP. Design We developed an algorithm to predict for individual infants the risk of later ROP development requiring treatment based on the postnatal longitudinal systemic factors of insulin-like growth factor I (IGF-I) level, IGF binding protein 3 level, and postnatal weight gain. We developed the algorithm based on 79 preterm infants considered at risk for ROP by standard criteria (gestational age, 23.6-31.7 weeks) in a longitudinal study measuring weight gain and serum IGF-I and IGF binding protein 3 levels weekly from birth until discharge from the hospital. We monitored deviations from reference models for weight and IGF-I level (preterm children who developed no or minimal ROP) to detect indications for treatable ROP by Early Treatment for Retinopathy of Prematurity study criteria. Results This monitoring method detected 6 (100%) of 6 infants in this cohort who required treatment for ROP with a warning signal at least 5 weeks before requiring treatment and at least 3 weeks before the onset of stage 3 ROP. The majority of infants (61/73 infants) requiring no treatment were also correctly identified. Conclusions Monitoring the postnatal factors of weight, IGF-I level, and IGF binding protein 3 level substantially enhances the clinician's ability to identify patients who will require treatment for ROP.
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| 6. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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Postnatal head growth deficit among premature infants parallels retinopathy of prematurity and insulin-like growth factor-1 deficit
- 2006
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Ingår i: Pediatrics. ; 117:6, s. 1930-8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We hypothesized that in premature infants, retinal vascular growth retardation between birth and postmenstrual age of approximately 30 to 32 weeks that initiates retinopathy of prematurity is paralleled by brain growth retardation. METHODS: In a prospective longitudinal study, we measured postnatal head growth, retinopathy of prematurity stage, protein and energy intake, severity of illness and serum insulin-like growth factor-1 levels in 58 preterm infants (mean gestational age at birth: 27.6 weeks) from birth until postmenstrual age of approximately 40 weeks. RESULTS: Premature infant head growth decelerates dramatically after birth until postmenstrual age of approximately 30 weeks. Head growth retardation coincides with retinal vascular growth suppression. Accelerated growth follows between post menstrual ages of approximately 30 to 32 weeks and approximately 40 weeks. The degree of head growth retardation up to postmenstrual age of 31 weeks corresponds to the degree of retinopathy of prematurity and to the degree of suppression of serum levels of insulin-like growth factor-1. At postmenstrual age of 31 weeks, if a child's head circumference SD is below -2.5, then the probability of also developing at least stage 3 retinopathy of prematurity increases fivefold compared with head circumference above -2.5 SD (32% vs 6%) suggesting parallel processes in brain and retina. Serum insulin-like growth factor-1 levels correlate positively with head circumference SD score and with the degree of retinopathy of prematurity. CONCLUSIONS: The correlation between head and retinal growth is consistent with insulin growth factor-1 being one of the postnatal growth factors involved in this multifactorial process and also suggests that factors that contribute to retinopathy of prematurity during this critical period may also affect neurological dysfunction. Additional studies are required to establish this connection.
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| 7. |
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| 8. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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Quantification and localization of the IGF/insulin system expression in retinal blood vessels and neurons during oxygen-induced retinopathy in mice
- 2009
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Ingår i: Invest Ophthalmol Vis Sci. - 1552-5783. ; 50:4, s. 1831-1837
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Retinopathy is a result of pathologic angiogenesis influenced by insulinlike growth factor (IGF)-1. The authors examined the local expression of the IGF/insulin family. METHODS: In retinas with and without oxygen-induced retinopathy, the authors assessed with real-time RT-PCR mRNA expression of the IGF-1 receptor (IGF-1R), insulin receptor (IR), IGF-1, IGF-2, insulin (Ins2), and IGF-binding protein 1 (IGFBP1) to IGFBP6 in total retina from postnatal day (P) 7 to P33 to examine changes over time with the induction of retinopathy and at P17 on laser-captured retinal components to quantitatively localize mRNA expression in the ganglion cell layer, the outer nuclear layer, the inner nuclear layer, normal blood vessels, and neovascular tufts. RESULTS: IGF-1R and IR are expressed predominantly in photoreceptors and in vessels, with scant expression in the rest of the neural retina. IGF-1R expression is more than 100-fold greater than IR. The major local growth factor (expressed in photoreceptors and in blood vessels) is IGF-2 (approximately 1000-fold greater than IGF-1). IGF-1 (approximately 600 copies/10(6) cyclophilin) is expressed throughout the retina. IGFBP2, IGFBP4, and IGFBP5 expression is unchanged with increasing retinal development and with the induction of retinopathy. In contrast, IGFBP3 expression increased more than 5-fold with hypoxia, found in neovascular tufts. CONCLUSIONS: IGF-1R, IR, and the ligand IGF-2 are expressed almost exclusively in photoreceptors and blood vessels. IGFBP3 and IGFBP5 expression increases in neovascular tufts compared with normal vessels. IGF-1 is expressed throughout the retina at much lower levels. These results suggest cross-talk between vessels and photoreceptors in the development of retinopathy and retinal vasculature.
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| 9. |
- Löfqvist, Chatarina, 1964, et al.
(författare)
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Validation of a new retinopathy of prematurity screening method monitoring longitudinal postnatal weight and insulinlike growth factor I.
- 2009
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Ingår i: Archives of ophthalmology. - : American Medical Association (AMA). - 1538-3601 .- 0003-9950. ; 127:5, s. 622-7
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To validate in a prospective study the surveillance algorithm WINROP for detecting infants at risk for proliferative retinopathy of prematurity (ROP). METHODS: Fifty preterm infants with a mean gestational age of 26 weeks were included. In the first step of WINROP, weekly measures of body weight and serum insulinlike growth factor I (IGF-I) level from birth until postmenstrual age 36 weeks are entered and compared with expected development. If any of the variables show a negative deviation to a certain degree, an alarm is given. In the second step, gestational age, birth weight, and IGF binding protein 3 level are entered. RESULTS: The WINROP algorithm identified all children (100% sensitivity) who were diagnosed with proliferative ROP 1.1 to 21.6 weeks later. No infants with no alarm or with alarm at low risk developed proliferative ROP. Alarm at high risk before postmenstrual age 32 weeks was given for 22 of 50 infants (44%); 9 of these infants developed proliferative ROP (54% specificity), of whom 8 were treated. CONCLUSION: The WINROP algorithm may be a useful tool for modification of ROP screening.
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