[Notch1/Akt/Foxo1 Pathway Regulated by Kisspeptin Is Involved in Endometrial Decidualization in Patients With Recurrent Spontaneous Abortion]. / kisspeptin调控Notch1/Akt/Foxo1é€šè·¯å‚ä¸Žå¤å‘æ€§æµäº§æ‚£è€ å­å®«å† è†œèœ•è†œåŒ–.

Objective: Kisspeptin, a protein encoded by the KISS1 gene, functions as an essential factor in suppressing tumor growth. The intricate orchestration of cellular processes such as proliferation and differentiation is governed by the Notch1/Akt/Foxo1 signaling pathway, which assumes a central role in maintaining cellular homeostasis. In the specific context of this investigation, the focal point lies in a meticulous exploration of the intricate mechanisms underlying the regulatory effect of kisspeptin on the process of endometrial decidualization. This investigation delves into the interplay between kisspeptin and the Notch1/Akt/Foxo1 signaling pathway, aiming to elucidate its significance in the pathophysiology of recurrent spontaneous abortion (RSA). Methods: We enrolled a cohort comprising 45 individuals diagnosed with RSA, who were admitted to the outpatient clinic of the Reproductive Center at the Second Affiliated Hospital of Soochow University between June 2020 and December 2020. On the other hand, an additional group of 50 women undergoing elective abortion at the outpatient clinic of the Family Planning Department during the same timeframe was also included. To comprehensively assess the molecular landscape, Western blot and RT-qPCR were performed to analyze the expression levels of kisspeptin (and its gene KISS1), IGFBP1 (an established marker of decidualization), Notch1, Akt, and Foxo1 within the decidua. Human endometrial stromal cells (hESC) were given targeted interventions, including treatment with siRNA to disrupt KISS1 or exposure to kisspeptin10 (the bioactive fragment of kisspeptin), and were subsequently designated as the siKP group or the KP10 group, respectively. A control group comprised hESC was transfected with blank siRNA, and cell proliferation was meticulously evaluated with CCK8 assay. Following in vitro induction for decidualization across the three experimental groups, immunofluorescence assay was performed to identify differences in Notch1 expression and decidualization morphology between the siKP and the KP10 groups. Furthermore, RT-qPCR and Western blot were performed to gauge the expression levels of IGFBP1, Notch1, Akt, and Foxo1 across the three cell groups. Subsequently, decidualization was induced in hESC by adding inhibitors targeting Notch1, Akt, and Foxo1. The expression profiles of the aforementioned proteins and genes in the four groups were then examined, with hESC induced for decidualization without adding inhibitors serving as the normal control group. To establish murine models of normal pregnancy (NP) and RSA, CBA/J×BALB/c and CBA/J×DBA/2 mice were used. The mice were respectively labeled as the NP model and RSA model. The experimental groups received intraperitoneal injections of kisspeptin10 and kisspeptin234 (acting as a blocker) and were designated as RSA-KP10 and NP-KP234 groups. On the other hand, the control groups received intraperitoneal injections of normal saline (NS) and were referred to as RSA-NS and NP-NS groups. Each group comprised 6 mice, and uterine tissues from embryos at 9.5 days of gestation were meticulously collected for observation of embryo absorption and examination of the expression of the aforementioned proteins and genes. Results: The analysis revealed that the expression levels of kisspeptin, IGFBP1, Notch1, Akt, and Foxo1 were significantly lower in patients diagnosed with RSA compared to those in women with NP (P<0.01 for kisspeptin and P<0.05 for IGFBP1, Notch1, Akt, and Foxo1). After the introduction of kisspeptin10 to hESC, there was an observed enhancement in decidualization capability. Subsequently, the expression levels of Notch1, Akt, and Foxo1 showed an increase, but they decreased after interference with KISS1. Through immunofluorescence analysis, it was observed that proliferative hESC displayed a slender morphology, but they transitioned to a rounder and larger morphology post-decidualization. Concurrently, the expression of Notch1 increased, suggesting enhanced decidualization upon the administration of kisspeptin10, but the expression decreased after interference with KISS1. Further experimentation involved treating hESC with inhibitors specific to Notch1, Akt, and Foxo1 separately, revealing a regulatory sequence of Notch1/Akt/Foxo1 (P<0.05). In comparison to the NS group, NP mice administered with kisspeptin234 exhibited increased fetal absorption rates (P<0.001) and decreased expression of IGFBP1, Notch1, Akt, and Foxo1 (P<0.05). Conversely, RSA mice administered with kisspeptin10 demonstrated decreased fetal absorption rates (P<0.001) and increased expression levels of the aforementioned molecules (P<0.05). Conclusion: It is suggested that kisspeptin might exert its regulatory influence on the process of decidualization through the modulation of the Notch1/Akt/Foxo1 signaling cascade. A down-regulation of the expression levels of kisspeptin could result in suboptimal decidualization, which in turn might contribute to the development or progression of RSA.

IGF-1 and IGFBP-1 as Possible Predictors of Response to Lifestyle Intervention-Results from Randomized Controlled Trials.

Lifestyle interventions can prevent type 2 diabetes (T2DM). However, some individuals do not experience anticipated improvements despite weight loss. Biomarkers to identify such individuals at early stages are lacking. Insulin-like growth factor 1 (IGF- 1) and Insulin-like growth factor binding protein 1(IGFBP-1) were shown to predict T2DM onset in prediabetes. We assessed whether these markers also predict the success of lifestyle interventions, thereby possibly guiding personalized strategies. We analyzed the fasting serum levels of IGF-1, IGFBP-1, and Insulin-like growth factor binding protein 2 (IGFBP-2) in relation to changes in metabolic and anthropometric parameters, including intrahepatic lipids (IHLs) and visceral adipose tissue (VAT) volume, measured by magnetic resonance imaging (MRI), in 345 participants with a high risk for prediabetes (54% female; aged 36-80 years). Participants were enrolled in three randomized dietary intervention trials and assessed both at baseline and one year post-intervention. Statistical analyses were performed using IBM SPSS Statistics (version 28), and significance was set at p < 0.05. Within the 1-year intervention, overall significant improvements were observed. Stratifying individuals by baseline IGF-1 and IGFBP-1 percentiles revealed significant differences: higher IGF-1 levels were associated with more favorable changes compared to lower levels, especially in VAT and IHL. Lower baseline IGFBP-1 levels were associated with greater improvements, especially in IHL and 2 h glucose. Higher bioactive IGF-1 levels might predict better metabolic outcomes following lifestyle interventions in prediabetes, potentially serving as biomarkers for personalized interventions.

Alterations in the pro-resolving lipid mediator machinery within first trimester maternal tissue: Implications in decidualization and miscarriage risk.

A pivotal event in uterine receptivity and human reproduction is the differentiation of endometrial stromal cells into decidual cells, known as decidualization. Decidualization is interlinked with its inflammatory environment. Our study aimed to investigate the presence and role of pro-resolving lipid mediators in first trimester maternal tissue. We assessed the levels of LXA4 and RvD1, along with their metabolic LOX enzymes, in elective (control) and sporadic miscarriage samples. We investigated the effects of LXA4 and RvD1 on decidualization using primary endometrial stromal cells and the immortalized endometrial stromal St-T1b cell line. The upregulation of 12- and 15-LOX expression was observed in pregnancy tissue after sporadic miscarriage, suggesting an inflammatory imbalance. Furthermore, incubation with these lipid mediators led to a decrease in decidualization biomarkers PRL and IGFBP-1, accompanied by morphological changes indicative of aberrant differentiation. The expression of LOX enzymes in decidual natural killer cells suggests their involvement in regulating the inflammatory surroundings and the extent of decidualization.

The diverging roles of insulin-like growth factor binding proteins in pulmonary arterial hypertension.

Pulmonary hypertension (PH) is a progressive, severe and to date not curable disease of the pulmonary vasculature. Alterations of the insulin-like growth factor 1 (IGF-1) system are known to play a role in vascular pathologies and IGF-binding proteins (IGFBPs) are important regulators of the bioavailability and function of IGFs. In this study, we show that circulating plasma levels of IGFBP-1, IGFBP-2 and IGFBP-3 are increased in idiopathic pulmonary arterial hypertension (IPAH) patients compared to healthy individuals. These binding proteins inhibit the IGF-1 induced IGF-1 receptor (IGF1R) phosphorylation and exhibit diverging effects on the IGF-1 induced signaling pathways in human pulmonary arterial cells (i.e. healthy as well as IPAH-hPASMCs, and healthy hPAECs). Furthermore, IGFBPs are differentially expressed in an experimental mouse model of PH. In hypoxic mouse lungs, IGFBP-1 mRNA expression is decreased whereas the mRNA for IGFBP-2 is increased. In contrast to IGFBP-1, IGFBP-2 shows vaso-constrictive properties in the murine pulmonary vasculature. Our analyses show that IGFBP-1 and IGFBP-2 exhibit diverging effects on IGF-1 signaling and display a unique IGF1R-independent kinase activation pattern in human pulmonary arterial smooth muscle cells (hPASMCs), which represent a major contributor of PAH pathobiology. Furthermore, we could show that IGFBP-2, in contrast to IGFBP-1, induces epidermal growth factor receptor (EGFR) signaling, Stat-3 activation and expression of Stat-3 target genes. Based on our results, we conclude that the IGFBP family, especially IGFBP-1, IGFBP-2 and IGFBP-3, are deregulated in PAH, that they affect IGF signaling and thereby regulate the cellular phenotype in PH.

Lysosome dynamics during human endometrial stromal cells decidualization: effect of para-nonylphenol.

During the process of decidualization, the stromal cells of the endometrium change dynamically to create a favorable environment for embryo implantation. Lysosome activity has often been associated with physiological changes in the endometrium during the preimplantation period and early pregnancy. In this study, the effect of para-nonylphenol (p-NP), an endocrine disruptor, on human immortalized endometrial stromal cells (tHESCs) was investigated. After exposure to p-NP (1 nM and 1 pM), the cells were examined for the decidualization markers connexin-43, insulin like growth factor binding protein 1 (IGFBP1), and prolactin. In addition, the effect of p-NP on lysosome biogenesis and exocytosis was investigated by examining the expression and localization of the transcription factor EB (TFEB) and that of the lysosomal-associated membrane protein 1 (LAMP-1). Finally, we evaluated the effect of p-NP on extracellular matrix (ECM) remodeling using a fibronectin assay. Our results showed that p-NP reduced the expression of prolactin protein, increased the nuclear localization of TFEB, and induced the increase and translocation of the lysosomal protein LAMP-1 to the membrane of tHESCs. The data indicate an impairment of decidualization and suggest an increase in lysosomal biogenesis and exocytosis, which is supported by the higher release of active cathepsin D by tHESCs. Given the importance of cathepsins in the processing and degradation of the ECM during trophoblast invasiveness and migration into the decidua, our results appear to be clear evidence of the negative effects of p-NP on endometrial processes that are fundamental to reproductive success and the establishment of pregnancy.NEW & NOTEWORTHY Endocrine disruptors, such as para-nonylphenol, affect the decidualization of human endometrial stromal cells with an impact on decidualization itself, lysosome biogenesis and exocytosis, and extracellular matrix remodeling. All these alterations may negatively impact embryo implantation with the success of reproduction and the establishment of pregnancy.

IGFBP1 stabilizes Umod expression through m6A modification to inhibit the occurrence and development of cystitis by blocking NF-κB and ERK signaling pathways.

Cystitis is a common disease closely associated with urinary tract infections, and the specific mechanisms underlying its occurrence and development remain largely unknown. In this study, we discovered that IGFBP1 suppresses the occurrence and development of cystitis by stabilizing the expression of Umod through m6A modification, inhibiting the NF-κB and ERK signaling pathways. Initially, we obtained a bladder cystitis-related transcriptome dataset from the GEO database and identified the characteristic genes Umod and IGFBP1. Further exploration revealed that IGFBP1 in primary cells of cystitis can stabilize the expression of Umod through m6A modification. Overexpression of both IGFBP1 and Umod significantly inhibited cell apoptosis and the NF-κB and ERK signaling pathways, ultimately suppressing the production of pro-inflammatory factors. Finally, using a rat model of cystitis, we demonstrated that overexpression of IGFBP1 stabilizes the expression of Umod, inhibits the NF-κB and ERK signaling pathways, reduces the production of pro-inflammatory factors, and thus prevents the occurrence and development of cystitis. Our study elucidates the crucial role of IGFBP1 and Umod in cystitis and reveals the molecular mechanisms that inhibit the occurrence and development of cystitis. This research holds promise for offering new insights into the treatment of cystitis in the future.

A Nonlinear Relation between Body Mass Index and Long-Term Poststroke Functional Outcome-The Importance of Insulin Resistance, Inflammation, and Insulin-like Growth Factor-Binding Protein-1.

Both high serum insulin-like growth factor-binding protein-1 (s-IGFBP-1) and insulin resistance (IR) are associated with poor functional outcome poststroke, whereas overweight body mass index (BMI; 25-30) is related to fewer deaths and favorable functional outcome in a phenomenon labeled "the obesity paradox". Furthermore, IGFBP-1 is inversely related to BMI, in contrast to the linear relation between IR and BMI. Here, we investigated s-IGFBP-1 and IR concerning BMI and 7-year poststroke functional outcome. We included 451 stroke patients from the Sahlgrenska Study on Ischemic Stroke (SAHLSIS) with baseline measurements of s-IGFBP1, homeostasis model assessment of IR (HOMA-IR), BMI (categories: normal-weight (8.5-25), overweight (25-30), and obesity (>30)), and high-sensitivity C-reactive protein (hs-CRP) as a measure of general inflammation. Associations with poor functional outcome (modified Rankin scale [mRS] score: 3-6) after 7 years were evaluated using multivariable binary logistic regression, with overweight as reference due to the nonlinear relationship. Both normal-weight (odds-ratio [OR] 2.32, 95% confidence interval [CI] 1.30-4.14) and obese (OR 2.25, 95% CI 1.08-4.71) patients had an increased risk of poor functional outcome, driven by deaths only in the normal-weight. In normal-weight, s-IGFBP-1 modestly attenuated (8.3%) this association. In the obese, the association was instead attenuated by HOMA-IR (22.4%) and hs-CRP (10.4%). Thus, a nonlinear relation between BMI and poor 7-year functional outcome was differently attenuated in the normal-weight and the obese.

Placental IGFBP1 levels during early pregnancy and the risk of insulin resistance and gestational diabetes.

Reduced insulin sensitivity (insulin resistance) is a hallmark of normal physiology in late pregnancy and also underlies gestational diabetes mellitus (GDM). We conducted transcriptomic profiling of 434 human placentas and identified a positive association between insulin-like growth factor binding protein 1 gene (IGFBP1) expression in the placenta and insulin sensitivity at ~26 weeks gestation. Circulating IGFBP1 protein levels rose over the course of pregnancy and declined postpartum, which, together with high gene expression levels in our placenta samples, suggests a placental or decidual source. Higher circulating IGFBP1 levels were associated with greater insulin sensitivity (lesser insulin resistance) at ~26 weeks gestation in the same cohort and in two additional pregnancy cohorts. In addition, low circulating IGFBP1 levels in early pregnancy predicted subsequent GDM diagnosis in two cohorts of pregnant women. These results implicate IGFBP1 in the glycemic physiology of pregnancy and suggest a role for placental IGFBP1 deficiency in GDM pathogenesis.

Insulin-like growth factor-1 (IGF-1) levels in multiple sclerosis patients: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Multiple sclerosis (MS) is a chronic progressive autoimmune disorder of the central nervous system (CNS) that can cause inflammation, demyelination, and axon degeneration. Insulin-like growth factor-1 (IGF-1) is a single-chain polypeptide mainly synthesized in the liver and brain. IGF-1 causes neuronal and non-neuronal cell proliferation, survival, and differentiation. Therefore, it can be used in treating neuro-demyelinating diseases such as MS. The current systematic review and meta-analysis aims to compare the levels of IGF-1 in MS patients and healthy controls and also investigates IGF binding proteins (IGF-BP) and growth hormone (GH) levels between MS patients and healthy controls. METHODS: In this study, we systematically searched electronic databases of PubMed, Scopus, Web of Science (WOS), and Google Scholar, up to December 2022. Studies that measured IGF-1, GH, IGFBP-1, IGFBP-2, or IGFBP-3 in MS patients and healthy controls in either blood or cerebral spinal fluid (CSF) were identified. We calculated Standardized mean differences (SMD) to compare levels of IGF-1, GH, IGFBP-1, IGFBP-2, or IGFBP-3 in MS patients and controls. RESULTS: Finally, we included 11 eligible studies from 1998 to 2018. The sample size of included studies varied from 20 to 200 resulting in a total sample size of 1067 individuals, 531 MS patients, and 536 healthy controls. The mean age of the patient and control groups were 38.96 and 39.38, respectively. The average EDSS among patients was 4.56. We found that blood levels of IGF-1 (SMD = 0.20, 95% CI = -0.20 to 0.59, I2 = 82.4%, K = 8, n = 692), CSF level of IGF-1 (SMD = 0.25, 95% CI = -0.06 to 0.56, I2 = 0.0%, K = 3 n = 164) and blood levels of GH were not significantly higher in MS patients than controls (SMD = 0.08, 95% CI = -0.33 to 0.49, I2 = 77.0% K = 3, n = 421). Moreover, the blood levels of IGFBP-1 (SMD = 0.70, 95% CI = 0.01 to 1.40, I2 = 77%, K = 4, n = 255) were significantly higher in MS cases than in controls. However, the blood levels of IGFBP-2 (SMD = 0.43, 95% CI = -0.34 to 1.21, I2 = 64.2%, K = 3, n = 78) and blood levels of IGFBP-3 (SMD = 1.04, 95% CI = -0.09 to 2.17, I2 = 95.6%, K = 6, n = 443) were not significantly higher in patients than controls. CONCLUSION: Our meta-analysis revealed no significant difference in serum levels of IGF-1, GH, IGFBP-2, and IGFBP-3 between the MS group and healthy controls, except for IGFBP1. However, our systematic review showed that the studies were controversial for IGFBP-3 serum levels. Some studies found an increase in serum level of IGFBP-3 in MS patients compared to the healthy group, while others showed a decrease.

Insulin-like Growth Factor Binding Proteins and Cellular Senescence Are Involved in the Progression of Non-Alcoholic Fatty Liver Disease and Fibrosis in a Mouse Model.

Background and Objectives: Non-alcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. It progresses from simple steatosis to non-alcoholic steatohepatitis (NASH). Fibrosis is often present during NAFLD progression; however, factors determining which subjects develop NASH or fibrosis are unclear. Insulin-like growth factor binding proteins (IGFBPs) are a family of secreted proteins involved in senescence and scarring, mainly synthetized in the liver. Here, we aimed to study the association of IGFBPs and their induced senescence with the progression of NAFLD and liver fibrosis. Materials and Methods: A total of 16-week-old male C57BL/6 mice weighing 23 ± 3 g were fed either methionine/choline-deficient (MCD) or control diet for 2, 8, or 12 weeks. Blood and liver samples were collected, and a histological assessment of NAFLD and fibrosis was performed. Fat contents were measured. Cellular senescence was evaluated in the liver. IGFBP levels were assessed in the liver and serum. Data were expressed as mean ± SD and analyzed by a one-way ANOVA followed by Tukey's test. Lineal regression models were applied for NAFLD and fibrosis progression. p < 0.05 was considered significant. Results: IGFBP-1 and -2 were increased in serum during NAFLD. IGFBP-7 was significantly increased in the serum in NASH compared with the controls. Senescence increased in NAFLD. Serum and liver IGFBP-7 as well as SA-ß-gal activity increased as fibrosis progressed. Both IGFBP-7 and cellular senescence were significantly higher during NAFLD and fibrosis in MCD-fed mice. Conclusions: IGFBP-1, -2, and -7, through their consequent senescence, have a role in the progression of NAFLD and its associated fibrosis, being a plausible determinant in the progression from steatosis to NASH.

Growth Hormone Mediators and Glycemic Control in Youths With Type 2 Diabetes: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Youth-onset type 2 diabetes (T2D) has a more aggressive phenotype than adult-onset T2D, including rapid loss of glycemic control and increased complication risk. Objective: To identify associations of growth hormone mediators with glycemic failure, beta cell function, and insulin sensitivity in youth-onset T2D. Design, Setting, and Participants: This post hoc secondary analysis of the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) randomized clinical trial, which enrolled participants from July 2004 to February 2009, included 398 participants from 15 university-affiliated medical centers with available plasma samples from baseline and 36 months. Participants were youths aged 10 to 17 years with a duration of T2D of less than 2 years who were randomized to metformin, metformin plus lifestyle intervention, or metformin plus rosiglitazone. Participants were followed up for a mean (SD) of 3.9 (1.5) years during the trial, ending in 2011. Statistical analysis was performed from August 2022 to November 2023. Exposure: Plasma insulin-like growth factor-1 (IGF-1), growth hormone receptor (GHR), and insulin-like growth factor binding protein 1 (IGFBP-1). Main Outcomes and Measures: Main outcomes were (1) loss of glycemic control during the TODAY study, defined as hemoglobin A1c (HbA1c) level of 8% or more for 6 months or inability to wean from insulin therapy, and (2) baseline and 36-month measures of glycemia (fasting glucose, HbA1c), insulin sensitivity (1/fasting C-peptide), high-molecular-weight adiponectin, and beta cell function (C-peptide index, C-peptide oral disposition index). Results: This analysis included 398 participants (mean [SD] age, 13.9 [2.0] years; 248 girls [62%]; 166 Hispanic participants [42%]; 134 non-Hispanic Black participants [34%], and 84 non-Hispanic White participants [21%]). A greater increase in IGF-1 level between baseline and 36 months was associated with lower odds of glycemic failure (odds ratio [OR], 0.995 [95% CI, 0.991-0.997]; P < .001) and higher C-peptide index per 100-ng/mL increase in IGF-1 (ß [SE], 0.015 [0.003]; P < .001). A greater increase in log2 GHR level between baseline and 36 months was associated with higher odds of glycemic failure (OR, 1.75 [95% CI, 1.05-2.99]; P = .04) and lower C-peptide index (ß [SE], -0.02 [0.006]; P < .001). A greater increase in log2 IGFBP-1 level between baseline and 36 months was associated with higher odds of glycemic failure (OR, 1.37 [95% CI, 1.09-1.74]; P = .007) and higher high-molecular-weight adiponectin (ß [SE], 431 [156]; P = .007). Conclusions and Relevance: This study suggests that changes in plasma growth hormone mediators are associated with loss of glycemic control in youth-onset T2D, with IGF-1 associated with lower risk and GHR and IGFBP-1 associated with increased risk. Trial Registration: ClinicalTrials.gov Identifier: NCT00081328.

Pregnancy associated plasma protein-A2 (PAPP-A2) and stanniocalcin-2 (STC2) but not PAPP-A are associated with circulating total IGF-1 in a human adult population.

The pappalysins pregnancy associated plasma protein-A (PAPP-A) and -A2 (PAPP-A2) act as proteinases of insulin-like growth factor-1 (IGF-1) binding proteins, while stanniocalcin-2 (STC2) was identified as a pappalysin inhibitor. While there is some evidence from studies in children and adolescents, it is unclear whether these molecules are related to concentrations of IGF-1 and its binding proteins in adults. We investigated cross-sectionally the association of circulating PAPP-A, PAPP-A2 and STC2 with IGF-1 and its binding proteins (IGFBPs) in 394 adult pretest participants (20-69 years) of the German National Cohort Berlin North study center. Plasma PAPP-A, PAPP-A2, total and free IGF-1, IGFBP-1, IGFBP-2, IGFBP-3, IGFBP-5 and STC2 were measured by ELISAs. The associations of PAPP-A, PAPP-A2 and STC2 with IGF-1 or IGFBPs were investigated using multivariable linear regression analyses adjusting for age, sex, body mass index and pretest phase. We observed significant inverse associations of PAPP-A2 (difference in concentrations per 0.5 ng/mL higher PAPP-A2 levels) with total IGF-1 (- 4.3 ng/mL; 95% CI - 7.0; - 1.6), the IGF-1:IGFBP-3 molar ratio (- 0.34%; 95%-CI - 0.59; - 0.09), but not free IGF-1 and a positive association with IGFBP-2 (11.9 ng/mL; 95% CI 5.0; 18.8). PAPP-A was not related to total or free IGF-1, but positively associated with IGFBP-5. STC2 was inversely related to total IGF-1, IGFBP-2 and IGFBP-3 and positively to IGFBP-1. This first investigation of these associations in a general adult population supports the hypothesis that PAPP-A2 as well as STC2 play a role for IGF-1 and its binding proteins, especially for total IGF-1. The role of PAPP-A2 and STC2 for health and disease in adults warrants further investigation.

Serum IGFBP-1 as a promising diagnostic and prognostic biomarker for colorectal cancer.

Our previous study showed that levels of circulating insulin-like growth factor binding protein-1 (IGFBP-1) has potential diagnostic value for early-stage upper gastrointestinal cancers. This study aimed to assess whether serum IGFBP-1 is a potential diagnostic and prognostic biomarker for CRC patients. IGFBP-1 mRNA expression profile data of peripheral blood in colorectal cancer (CRC) patients were downloaded and analyzed from Gene Expression Omnibus database. We detected serum IGFBP-1 in 138 CRC patients and 190 normal controls using enzyme-linked immunosorbent assay. Blood IGFBP-1 mRNA levels were higher in CRC patients than those in normal controls (P = 0.027). In addition, serum IGFBP-1 protein levels in the CRC group were significantly higher than those in normal control group (P < 0.0001). Serum IGFBP-1 demonstrated better diagnostic accuracy for all CRC and early-stage CRC, respectively, when compared with carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA 19-9) or the combination of CEA and CA19-9. Furthermore, Cox multivariate analysis revealed that serum IGFBP-1 was an independent prognostic factor for OS (HR = 2.043, P = 0.045). Our study demonstrated that serum IGFBP-1 might be a potential biomarker for the diagnosis and prognosis of CRC. In addition, the nomogram might be helpful to predict the prognosis of CRC.

AMPK-mTORC1 pathway mediates hepatic IGFBP-1 phosphorylation in glucose deprivation: a potential molecular mechanism of hypoglycemia-induced impaired fetal growth.

Mechanisms underlying limitations in glucose supply that restrict fetal growth are not well established. IGF-1 is an important regulator of fetal growth and IGF-1 bioavailability is markedly inhibited by IGFBP-1 especially when the binding protein is hyperphosphorylated. We hypothesized that the AMPK-mTORC1 pathway increases IGFBP-1 phosphorylation in response to glucose deprivation. Glucose deprivation in HepG2 cells activated AMPK and TSC2, inhibited mTORC1 and increased IGFBP-1 secretion and site-specific phosphorylation. Glucose deprivation also decreased IGF-1 bioavailability and IGF-dependent activation of IGF-1R. AICAR (an AMPK activator) activated TSC2, inhibited mTORC1, and increased IGFBP-1 secretion/phosphorylation. Further, siRNA silencing of either AMPK or TSC2 prevented mTORC1 inhibition and IGFBP-1 secretion and phosphorylation in glucose deprivation. Our data suggest that the increase in IGFBP-1 phosphorylation in response to glucose deprivation is mediated by the activation of AMPK/TSC2 and inhibition of mTORC1, providing a possible mechanistic link between glucose deprivation and restricted fetal growth.

Association of TNF-α, IGF-1, and IGFBP-1 levels with the severity of osteopenia in mice with nonalcoholic fatty liver disease.

BACKGROUNDS: Nonalcoholic fatty liver disease (NAFLD) exhibits a close association with osteoporosis. This work aims to assess the potential effects of NAFLD on the progression of osteopenia in animal models. METHODS: Forty-eight C57BL/6 female mice were randomly divided to wild-type (WT) group and high-fat diet (HFD) group. The corresponding detections were performed after sacrifice at 16, 24 and 32 weeks, respectively. RESULTS: At 16 weeks, an remarkable increase in body weight and lipid aggregation in the hepatocytes of HFD group was observed compared to the WT group, while the bone structure parameters showed no significant difference. At 24 weeks, the levels of TNF-α and IL-6 in NAFLD mice were significantly increased, while the level of osteoprotegerin mRNA in bone tissue was decreased, and the level of receptor activator of nuclear factor Kappa-B ligand mRNA was increased. Meanwhile, the function of osteoclasts was increased, and the bone microstructure parameters showed significant changes. At 32 weeks, in the HFD mice, the mRNA levels of insulin-like growth factor-1 (IGF-1), runt-related transcription factor 2, and osterix mRNA were reduced, while the insulin-like growth factor binding protein-1 (IGFBP-1) level was increased. Simultaneously, the osteoblast function was decreased, and the differences of bone structure parameters were more significant, showing obvious osteoporosis. CONCLUSIONS: The bone loss in HFD mice is pronounced as NAFLD progresses, and the changes of the TNF-α, IL-6, IGF-1, and IGFBP-1 levels may play critical roles at the different stages of NAFLD in HFD.

Impaired decidualization and relative increase of PROK1 expression in the decidua of patients with unexplained recurrent pregnancy loss showing insulin resistance.

A recent meta-analysis revealed that patients with unexplained recurrent pregnancy loss (RPL) show higher insulin resistance compared to healthy controls. However, the etiology of RPL remains unknown. Prokineticin (PROK1), a pleiotropic uterine endometrial protein, is important for implantation and decidualization and is regulated by hypoxia and insulin. In this study, we investigated the decidualization status and the role of PROK1 in the decidua of patients with unexplained RPL showing insulin resistance. Thirty-two patients with unexplained RPL were included in this study. Following the diagnosis of a miscarriage, the decidua and villi of the patient were surgically collected. Fasting blood glucose and insulin levels were measured, and HOMA-ß was calculated. Using IHC and ELISA, the expression of IGFBP-1, PRL and PROK1 in the decidua and IGF-2 in the villi were analyzed in patients with euploid miscarriage with a high HOMA-ß index (n = 8) and compared to controls (euploid miscarriage with normal HOMA-ß: n = 12, aneuploid miscarriage with normal HOMA-ß: n = 12). The co-localization of PROK1 and IGFBP-1 was observed in the decidua by IHC. In the decidua of RPL patients with high HOMA-ß, the expression levels of IGFBP-1 and PRL were significantly lower, whereas the PROK1/IGFBP-1 ratio was significantly higher compared to that of the controls. IGF-2 expression in villi was significantly lower in RPL patients with high HOMA-ß. Impaired decidualization and excessive PROK1 production may have pathological implications in patients with unexplained RPL with insulin resistance, especially under the state of hyper insulin production.

Exploring the role of insulin-like growth factor binding protein-1 in identifying idiopathic multicentric Castleman's disease types: Implications for the mTOR signaling pathway.

OBJECTIVE: To determine the molecular differences between iMCD-thrombocytopenia, anasarca, fevers, reticulin myelofibrosis, organomegaly (TAFRO), and iMCD-not otherwise specified (NOS). METHODS: CD4-positive T cells were isolated from two iMCD-TAFRO and two iMCD-NOS patients for RNA sequencing comparison. Serum proteins of two iMCD-TAFRO and four iMCD-NOS patients were comprehensively analyzed to identify pathogenesis-associated proteins. IGFBP-1 protein, extracted from serum analysis, was compared to healthy controls, iMCD, systemic lupus erythematosus, and rheumatoid arthritis patients. RESULTS: RNA sequencing of CD4-positive T cells revealed enhanced mTOR-related signaling in iMCD-TAFRO compared to iMCD-NOS. Comprehensive serum analysis found IGFBP-1 linked to iMCD pathogenesis, significantly higher in iMCD-TAFRO. This protein may be elevated in patients with iMCD caused by an enhanced mTOR pathway. CONCLUSION: The mTOR pathway is suggested to be activated in iMCD-TAFRO compared to iMCD-NOS, which may elevate the protein IGFBP-1. This protein may be a biomarker to distinguish iMCD-TAFRO from iMCD-NOS.

Insulin Signaling Through the Insulin Receptor Increases Linear Growth Through Effects on Bone and the GH-IGF-1 Axis.

CONTEXT: Childhood overnutrition is associated with increased growth and bone mineral density (BMD) vs the opposite for undernutrition. The role of insulin receptor (InsR) signaling in these phenotypes is unclear. Rare disease patients with hyperinsulinemia and impaired InsR function (homozygous [-/-] or heterozygous [+/-] INSR pathogenic variants, type B insulin resistance [TBIR]) model increased InsR signaling, while patients with intact InsR function (congenital generalized lipodystrophy, CGL) model decreased InsR signaling. OBJECTIVE: This work aimed to understand mechanisms whereby InsR signaling influences growth. METHODS: A cross-sectional comparison was conducted of CGL (N = 23), INSR-/- (N = 13), INSR+/- (N = 17), and TBIR (N = 8) at the National Institutes of Health. Main outcome measures included SD scores (SDS) for height, body mass index, insulin-like growth factor (IGF)-1, and BMD, and IGF binding proteins (IGFBP)-1 and -3. RESULTS: INSR-/- vs CGL had higher insulin (median 266 [222-457] vs 33 [15-55] mcU/mL), higher IGFBP-1 (72 350 [55 571-103 107] vs 6453 [1634-26 674] pg/mL), lower BMI SDS (-0.7 ± 1.1 vs 0.5 ± 0.9), lower height SDS (-1.9[-4.3 to -1.3] vs 1.1 [0.5-2.5]), lower BMD SDS (-1.9 ± 1.4 vs 1.9 ± 0.7), and lower IGFBP-3 (0.37 [0.19-1.05] vs 2.00 [1.45-2.67] µg/mL) (P < .05 for all). INSR +/- were variable. Remission of TBIR lowered insulin and IGFBP-1, and increased IGF-1 and IGFBP-3 (P < .05). CONCLUSION: Patients with hyperinsulinemia and impaired InsR function exhibit impaired growth and lower BMD, whereas elevated InsR signaling (CGL) causes accelerated growth and higher BMD. These patients demonstrate that insulin action through the InsR stimulates direct anabolic effects in bone and indirect actions through the growth hormone (GH)-IGF-1 axis. TBIR patients exhibit abnormalities in the GH axis that resolve when InsR signaling is restored, supporting a causal relationship between InsR and GH axis signaling.

Activation of SGK1/ENaC Signaling Pathway Improves the Level of Decidualization in Unexplained Recurrent Spontaneous Abortion.

Recurrent spontaneous abortion (RSA) is one of the most common complications during pregnancy and seriously affects women's physical and mental health. About 50% of RSA cases are of unknown etiology. Our previous study found that the decidual tissue of patients with unexplained recurrent spontaneous abortion (URSA) had low expression levels of serum and glucocorticoid-induced protein kinase (SGK) 1. Endometrial decidualization is a key link in the early stage of pregnancy and is crucial to the development and maintenance of pregnancy. Decidualization is the proliferation and differentiation of endometrial stromal cells into deciduals, which involves a complex physiological process such as ovarian steroid hormones (estrogen, progesterone, prolactin, etc.), growth factors, and intercellular signaling. The binding of estrogen and its receptor stimulates the synthesis of endometrial deciduating markers prolactin (PRL) and insulin-like growth factor binding protein 1 (IGFBP-1), which mediates the occurrence of decidualization. Among them, SGK1/ENaC is a signaling pathway closely related to decidualization. The purpose of this study was to further investigate the expression of SGK1 and decidualization-related molecules in the decidual tissue of URSA patients and to explore the potential mechanism of SGK1's protective effect in URSA patients and in mouse models. Decidual tissue samples from 30 URSA patients and 30 women who actively terminated pregnancy were collected, and a URSA mouse model was established and treated with dydrogesterone. Expression levels of SGK1 and its signaling pathway-related proteins (p-Nedd4-2, 14-3-3 protein and ENaC-a), estrogen and progesterone receptors (ERß, PR), and decidualization markers (PRLR, IGFBP-1) were assessed. Our study found that SGK1, p-Nedd4-2, 14-3-3 proteins, and ENaC-a expression levels were reduced in the decidual tissue, the SGK1/ENaC signaling pathway was inhibited, and the expression levels of the decidualization markers PRLR and IGFBP-1 were downregulated in the URSA group compared with the controls. Additionally, the concentrations of E2, P, and PRL in the serum of mice were decreased in the URSA group compared with the controls. However, SGK1/ENaC pathway-related proteins, estrogen and progesterone and their receptors, and decidualization-related molecules were upregulated by dydrogesterone. These data suggest that estrogen and progesterone can induce decidualization by activating the SGK1/ENaC signaling pathway; disruption of this pathway can lead to the development of URSA. Dydrogesterone can increase the expression level of SGK1 protein in decidual tissue.