IGF-I and visfatin levels in retinopathy of prematurity

Insulin-like growth factor-1 and retinopathy of prematurity: A systemic review and meta-analysis

The prevalence of retinopathy of prematurity (ROP) is rapidly increasing worldwide. Many researchers have explored the relationship between insulin-like growth factor-1 (IGF-1) and ROP; however, the results are controversial. This meta-analysis evaluates the correlation between IGF-1 and ROP systematically. We searched for PubMed, Web of Science, Embase, the Cochrane Central Register of Controlled Trials, Ovid MEDLINE, SinoMed, ClinicalTrials.gov, and 3 Chinese databases up to June 2022. Then, the meta-regression and subgroup analysis were carried out. Twelve articles with 912 neonates were included in this meta-analysis. The results revealed that 4 of 7 covariates account for significant heterogeneity: location, measurement method of IGF-1 levels, collection time of blood sample, and the severity of ROP. The pooled analysis showed that low IGF-1 levels could serve as a risk factor associated with the development and severity of ROP. Serum IGF-1 monitoring in preterm infants after birth will be helpful in the diagnosis and treatment of ROP, and the reference value of IGF-1 should be standardized according to the measurement of IGF-1 and the region, as well as the postmenstrual age of prematurity.

Systemic Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a vasoproliferative vitreoretinal disorder, is the leading cause of childhood blindness worldwide. Although angiogenic pathways have been the main focus, cytokine-mediated inflammation is also involved in ROP etiology. Herein, we illustrate the characteristics and actions of all cytokines involved in ROP pathogenesis. The two-phase (vaso-obliteration followed by vasoproliferation) theory outlines the evaluation of cytokines in a time-dependent manner. Levels of cytokines may even differ between the blood and the vitreous. Data from animal models of oxygen-induced retinopathy are also valuable. Although conventional cryotherapy and laser photocoagulation are well established and anti-vascular endothelial growth factor agents are available, less destructive novel therapeutics that can precisely target the signaling pathways are required. Linking the cytokines involved in ROP to other maternal and neonatal diseases and conditions provides insights into the management of ROP. Suppressing disordered retinal angiogenesis via the modulation of hypoxia-inducible factor, supplementation of insulin-like growth factor (IGF)-1/IGF-binding protein 3 complex, erythropoietin, and its derivatives, polyunsaturated fatty acids, and inhibition of secretogranin III have attracted the attention of researchers. Recently, gut microbiota modulation, non-coding RNAs, and gene therapies have shown promise in regulating ROP. These emerging therapeutics can be used to treat preterm infants with ROP.

Novel Potential Biomarkers for Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is the main risk factor for vision-threatening disease in premature infants with low birth weight. An accumulating number of independent studies have focused on ROP pathogenesis and have demonstrated that laser photocoagulation therapy and/or anti-VEGF treatment are effective. However, early diagnosis of ROP is still critical. At present, the main method of ROP screening is based on binocular indirect ophthalmoscopy. However, the judgment of whether ROP occurs and whether treatment is necessary depends largely on ophthalmologists with a great deal of experience. Therefore, it is essential to develop a simple, accurate and effective diagnostic method. This review describes recent findings on novel biomarkers for the prediction, diagnosis and prognosis of ROP patients. The novel biomarkers were separated into the following categories: metabolites, cytokines and growth factors, non-coding RNAs, iconography, gut microbiota, oxidative stress biomarkers, and others. Biomarkers with high sensitivity and specificity are urgently needed for the clinical applications of ROP. In addition, using non-invasive or minimally invasive methods to obtain samples is also important. Our review provides an overview of potential biomarkers of ROP.

Targeted Blood Metabolomic Study on Retinopathy of Prematurity

Purpose

This study aims at exploring alterations of major metabolites and metabolic pathways in retinopathy of prematurity (ROP) infants and identifying biomarkers that may merit early diagnosis of ROP.

Methods

We analyzed targeted metabolites from 81 premature infants (<34 weeks of gestational age), including 40 ROP cases (15 males and 25 females, birth weight 1.263 ± 0. 345 kg, gestational age 31.20 ± 4.62 weeks) and 41 cases (30 males, 11 females, birth weight 1.220 ± 0.293 kg, gestational age 30.96 ± 4.17 weeks) of well-matched non-ROP controls. Metabolites were measured by ultra-performance liquid chromatography-tandem mass spectrometry. Standard multivariate and univariate analysis was performed to interpret metabolomic results.

Results

Glycine, glutamate, leucine, serine, piperidine, valine, tryptophan, citrulline, malonyl carnitine (C3DC), and homocysteine were identified as the top discriminant metabolites. In particular, discriminant concentrations of C3DC and glycine were also confirmed by univariate analysis as statistically significant different between ROP and non-ROP infants.

Conclusions

This study gained an insight into the metabolomic aspects of ROP development. We suggest that higher blood levels of C3DC and glycine can be promising biomarkers to predict the occurrence, but not the severity of ROP.

The correlation between insulin-like growth factor 1 (IGF-1) and novel adipocytokines in postmenopausal women: A population-based study

The adipocytokines and insulin-like growth factor 1 (IGF-1) are involved in insulin resistance, the cardiometabolic syndrome, and atherosclerosis. Therefore, investigating the relationship between circulating levels of the novel adipocytokines and IGF-1 is worthwhile. The correlation between IGF-1, visfatin, and omentin-1 has not been adequately investigated. In a population-based study, 324 postmenopausal women were randomly selected. Circulating IGF-1, visfatin, omentin-1, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) levels were measured with the highly specific enzyme-linked immunosorbent assay method. In multiple regression analyses adjusted for alkaline phosphatase, osteocalcin, and hs-CRP, circulating IGF-1 was significantly correlated with visfatin levels (standardized β coefficient [β] = 0.13, partial correlation coefficient [r] = 0.12, p = 0.028). The significant positive correlation between serum IGF-1 and visfatin levels remained after additional adjustments for age and BMI (β = 0.12, r = 0.12, p = 0.025), metabolic syndrome (β = 0.13, r = 0.12, p = 0.021), and type 2 diabetes mellitus (β = 0.13, r = 0.12, p = 0.026). No significant correlations were found between IGF-1, adiponectin, and omentin-1. There is a significant correlation between serum IGF-1 and visfatin levels in postmenopausal women beyond metabolic syndrome, type 2 diabetes, bone formation markers, and hs-CRP levels. The observed correlation between higher circulating IGF-1 and the higher visfatin levels might be a physiological compensation and adaptation to protect against visfatin-induced proinflammatory effects.

Correlation between cord blood apelin and IGF-1 levels in retinopathy of prematurity

Aim: We hypothesized that circulating apelin concentrations in preterm babies might be linked with retinopathy of prematurity (ROP), similar to IGF-1 levels. Patients & methods: A total of 97 infants born with a gestational age before 32 weeks in 2007–2009 were screened for ROP at the Gata Haydarpasa Hospital (Turkey). Fourteen of them with classified ROP stage 3–5 comprised our study group. Results: The non-ROP group had higher apelin and IGF-1 levels than ROP neonates at birth. After 4–6 weeks, postnatal ROP subjects had lower apelin and IGF-1 levels than non-ROP controls. At the end of the study, the change in apelin levels was positively correlated with the change in IGF-1 levels (r = 0.852; p = 0.01). Conclusion: We suggested that the pathogenesis of ROP, which is regarded as a neovascular retinal disorder, includes variations in the levels of apelin and IGF-1.