IGF-binding Protein-3 Levels Research Articles

Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) measurement in the detection of significant CAD in acute chest pain patients triaged using the No Objective Testing (NOT) rule

Abstract Background After rule-out of MI in ED chest pain patients, uncertainty exists with respect to which remaining patients would benefit from objective functional/anatomical testing to detect potential underlying CAD. Using proteomics, we experimentally identified IGFBP-3 as a biomarker to assist this risk stratification and applied its measurement to >3,000 ED patients from 3 separate studies. Methods An isolated rat heart perfusate model coupled to mass spectrometry identified markers of cardiac ischemia. Human cardiac ischemia was carried out using cardiac exercise stress testing (EST, n=12). Temporal changes in IGFBP-3 during experimental MI were determined in patients undergoing septal alcohol ablation (SAA, n=12) and arterio-venous gradients of IGFBP-3 were determined from cases of proscribed cardiac catheterisation (CC, n=14). The ability of IGFBP-3 to assist clinical assessment (ROC analyses, logistic regression, C-statistic, pathways analyses) and ED risk assessment by the No Objective Testing (NOT) rule was carried out on samples from 3 prospectively recruited studies (SPACE, NZ, n=766; APACE, CH, n=1,056; FAST-TRAC, USA, n=1,230). Results IGFBP-3 identified by MS was present in perfusates of ischemic hearts only (n=3). In human cardiac EST, a delta of IGFBP-3 (∆IGFBP-3) between 0-150minutes was seen in positive ischemic tests, but not in controls (n=6 per group, p=0.026). In SAA patients, peripheral IGFBP-3 levels did not change over 24 hours (n=12, p=0.573) whereas in CC patients, significant extraction gradients of IGFBP-3 were seen across the heart and liver (p=0.013, n=14). In ED chest pain patients identified by the NOT rule (n=1,708), ΔIGFBP-3 between presentation and +2 hours (∆ IGFBP-3) was an independent logistic model predictor of unstable angina (n=123) alongside age, sex, cholesterol and Hx of CAD/MI. At 90% specificity, ∆IGFBP-3 improved the sensitivity of the model from 31% to 43%, the PPV 20% to 25% and the NPV from 94% to 95% (p=0.020). IGFBP-3 made a small improvement in "low risk" NOT rule patient identification (29% to 30%), but made a larger improvement to the ROC curve based identification in NOT rule patients for the finding of stenosis >70% on angiography (n=101, AUC clinical model = 0.682; model plus ∆ IGFBP-3 = 0.725, p=0.044). Pathways analyses (that included hs-TnT) in angiography patients (n=224) revealed ∆IGFBP-3 generated a 28% relative increase in low risk case identification (n=46 to 59). Conclusions IGFBP-3 is identified as a novel potential biomarker of cardiac ischemia, that is taken up/degraded across the heart and appears less responsive to complete infarction (MI). 0-2 hour changes in IGFBP-3 (∆ IGFBP-3) in patients identified as eligible for ED based NOT rule inclusion show promise as a useful tool to identify those with significant CAD, evidenced by the diagnosis of unstable angina, positive EST results or findings of 70% occlusion on angiography.

Insulin-like growth factor binding protein 2 predicts course of concomitant right-ventricular dilation and tricuspid regurgitation after transcatheter edge-to-edge mitral valve repair

Abstract Aims Right ventricular (RV) dilation and secondary tricuspid regurgitation (TR) are highly prevalent comorbidities in patients with mitral regurgitation and are associated with a worse prognosis. TR improvement after successful transcatheter edge-to-edge mitral valve repair (M-TEER) is reported regularly, however specific factors contributing to the recovery of RV function and TR after M-TEER are poorly understood. Particularly the role of serum biomarkers in this context is unclear. We aimed to identify specific biomarkers associated with the course of concomitant RV dilation and TR after M-TEER. Methods and Results We prospectively included 242 patients undergoing M-TEER at our center and obtained pre-procedural blood samples for biomarker analysis. A commercial multiplex protein assay (Cardiovascular III, Olink, Uppsala, Sweden) was used to quantify expression levels of 92 defined biomarkers. We then analyzed differences in biomarker expression between patients with and without right ventricular reverse remodeling (RVRR) as defined by improvement of concomitant TR by at least one grade and/or downsizing of the basal RV diameter of at least 10%. 242 patients were included in this analysis, 94 had no/mild concomitant TR at baseline, 148 had moderate/severe TR. RV diameters correlated with TR severity and were significantly larger in patients with moderate/severe TR. At baseline, expression of numerous cardiometabolic biomarkers was significantly higher in patients with moderate/severe TR. These included NT-proBNP (1.9-fold, p < 0.001), matrix metalloproteinase 2 (1.4-fold, p < 0.001) as well as insulin-like growth factor binding proteins 1 (1.7-fold, p < 0.001), -2 (1.3-fold, p = 0.001) and -7 (1.4-fold, p < 0.001). Follow-up analysis was performed in patients with initial moderate/severe TR. The course of TR and RV dimensions three months after M-TEER could be assessed in 99 patients (56 with moderate TR, 43 with severe TR). RVRR had occurred in 50 patients (50.5%). Patients without RVRR had a higher prevalence of chronic pulmonary disease (24.5 vs. 2.2%, p < 0.001). No further differences in clinical characteristics were found. Specifically, RV diameter, systolic pulmonary artery pressure (sPAP) and right-ventricular systolic function did not differ substantially between both groups. Strikingly however, the expression of insulin-like growth factor binding protein 2 (IGFBP-2) was significantly higher in patients, who did not develop RVRR (fold change 1.3 compared to patients with RVRR, p = 0.022). After adjustment for covariates IGFBP-2 was independently associated with absence of RVRR (Odds Ratio 2.078, 95% Confidence interval 1.108 – 3.897, p = 0.023). Conclusions In patients undergoing M-TEER with concomitant moderate or severe TR, numerous cardiometabolic biomarkers including IGFBP-2 are upregulated. Higher levels of IGFBP-2 at baseline are independently associated with persistent TR and/or RV dilation after M-TEER.

Urinary Biomarkers Associated With Pathogenic Pathways Reflecting Histologic Findings in Lupus Nephritis.

There is a pressing need to understand the pathogenesis of histologic findings and identify the biomarkers for predicting the histologic severity in lupus nephritis (LN). This study aimed to identify the pathogenic signal pathway and elucidate urinary biomarkers for predicting the presence or severity of histologic findings in LN. Urine samples from patients with biopsy-proven active LN were screened for 1,305 proteins using an aptamer-based proteomic assay. The diversity and expansion of individual renal histologic features in LN were quantified to identify the urinary proteins associated with the histologic findings found in each score. Candidate urinary proteins were validated in a validation cohort. Immunohistochemical staining of the renal tissues was performed to clarify the localization of the candidate proteins. Cluster analysis extracted five histologic subgroups according to their correlations with each histologic finding in LN. Protein groups that correlated with each histologic subgroup revealed a distinct pathogenesis in LN using pathway analyses. Enzyme-linked immunosorbent assay validation revealed that urinary calgranulin B (S100A9), monocyte chemotactic protein 1 (MCP-1), and insulin-like growth factor binding protein 5 (IGFBP-5) levels could specifically predict the presence and severity of active glomerular lesions, interstitial inflammation, and interstitial fibrosis, respectively. Immunohistochemical staining revealed the localization of these proteins in each lesion. Renal histologic findings may reflect the different pathogeneses involved in each lesion, and estimating the urinary calgranulin B, MCP-1, and IGFBP-5 levels may be useful in predicting the presence and severity of histologic findings in LN.

Establishment of IGF-1 and IGFBP-3 continuous reference percentiles from data of healthy children using three kinds of immunoassay systems

Background and aimsAppropriate continuous reference intervals (RIs) for serum insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3) are important for diagnosing growth hormone deficiency or excess. Material and methodsWe retrospectively reviewed serum IGF-1 and IGFBP-3 levels in Korean children aged 0–17 years who were diagnosed as healthy during a short stature workup in the outpatient clinics of three hospitals. IGF-1 and IGFBP-3 levels were measured using various immunoassays, including Liaison XL for IGF-1, an immunoradiometric assay (IRMA) for IGFBP-3 (n = 5522), and Immulite 2000 (n = 3036) and cobas e801 (n = 314). We established RIs from the 2.5th to 97.5th percentile RI curves using the lambda–mu–sigma (LMS) method for each sex group. ResultsPediatric serum continuous IGF-1 and IGFBP-3 reference percentiles by LMS method were found to be immunoassay method-dependent, but aligned relatively well with the manufacturers’ RIs. IGFBP-3 levels displayed notable discrepancies among the different immunoassay methods. ConclusionAge- and sex-specific pediatric LMS based continuous reference intervals are method dependent and they should be calculated for dynamic parameters that show variations throughout childhood.

Abstract B006: The role of tumor specific IGFBP-3 in the onset and progression of skeletal muscle wasting in a murine model of pancreatic cancer

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer- related death and is highly associated with skeletal muscle wasting (SMW) that leads to treatment intolerance and reduced survival. Research substantiates the role of increased levels of Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) in PDAC-related SMW. Canonically, supraphysiological levels of IGFBP-3 block insulin-like growth factor-1 (IGF-1) binding, thus downregulating the activation of its downstream targets Akt and mTOR. Non-canonical signaling via TGF-βRI results in aberrant FoxO1 signaling, which upregulates the ubiquitin proteasome pathway (UPP) and induces autophagy. Dysregulated UPP and autophagy activation have been shown to promote muscle degradation. Recent findings from our lab implicate canonical and non-canonical signaling of tumor associated IGFBP-3 in increased protein catabolism and decreased anabolism, resulting in SMW in a syngeneic murine model of PDAC. We tested the hypothesis that genetic ablation of IGFBP-3 in PDAC tumor cells attenuates SMW via regulation of Akt and FoxO1, leading to decreases in UPP and autophagy in skeletal muscle.Methods: C57BL/6J female mice (6-8 weeks) were randomized to one of three groups: 1) no tumor control (NTC) (n=10), 2) KCKO-Luc parental cells (PDAC) (n=14), or 3) IGFBP-3-/- KCKO-Luc (n=14). Tumor cells were injected orthotopically. Tumor and lean mass were assessed longitudinally via dual energy x-ray absorptiometry (DEXA). At sacrifice, quadriceps muscles were collected for protein and transcriptional analysis, Tibialis Anterior (TA) muscles for histology and serum for ELISA. TA frozen sections were stained with Oil Red O (ORO) to highlight intramuscular adipogenesis.Results: PDAC mice experience significantly reduced survival (T1/2=56 days) compared to IGFBP-3-/- mice that maintained 100% survival at day 100 (p<0.0001). IGFBP-3-/- mice lost significantly less lean mass from baseline to day 56 compared to PDAC mice (p<0.0001). PDAC mice exhibited 3-fold elevated serum levels of IGFBP-3 compared to NTC and IGFBP-3-/- mice (p<0.01). Transcriptionally, PDAC mice displayed increased expression of igfbp3, tgfbr1, and UPP associated genes fbxo32, and trim63 compared to NTC and IGFBP-3-/- mice. Further, the ratio of pAkt (Ser473), pS6 (Ser235/236), and pFoxO1 (Ser253) to total protein levels were significantly reduced in PDAC mice (p<0.05 vs NTC and IGFBP-3-/-). Additionally, protein levels of ULK1 and the ratio of LC3bII over LC3bI, markers of autophagy, are elevated in PDAC mice compared to NTC and IGFBP-3-/- mice (p<0.05). Lastly, there is a significant increase in ORO positive staining in PDAC mice compared to NTC and IGFBP-3-/- mice (p<0.0001).Conclusion: These findings suggest that PDAC-related SMW is driven by tumor derived IGFBP-3, which acts as an endocrine factor on skeletal muscle cells to inhibit protein synthesis and activate FoxO1 signaling to upregulate the UPP and autophagy. Lastly, we identify skeletal muscle adipogenesis as a biomarker for autophagy upregulation and SMW. Citation Format: Zachary R Sechrist, Calvin L Cole. The role of tumor specific IGFBP-3 in the onset and progression of skeletal muscle wasting in a murine model of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B006.

Dynamic changes in insulin-like growth factor binding protein expression occur between embryonic and early post-hatch development in broiler chickens

Somatotropic gene expression has been altered by genetic selection, and developmental changes in insulin-like growth factor (IGF) and IGF binding protein (IGFBP) expression may contribute to rapid growth and muscle accretion in commercial broilers. The objective of this study was to evaluate changes in somatotropic axis activity between embryonic day (e) 12 and post-hatch day (d) 21. Liver and breast muscle (pectoralis major) were collected to measure gene expression, and blood was collected post-hatch to measure circulating IGFs. Liver IGF1 rose rapidly post-hatch and, in muscle, IGF1 exhibited a dynamic expression pattern. Levels decreased from e14 to e20, returned to e14 levels at d3, decreased again at d10, and stayed low thereafter. In both tissues, mRNA levels of several IGFBPs changed between embryogenesis and post-hatch. Liver IGFBP2 increased between e12 and e20, returned to e12 levels on d1, and remained low. Conversely, liver IGFBP4 expression was greater post-hatch than during embryogenesis. Expression of select IGFBPs was depressed in liver during the peri-hatch period. Liver IGFBP1, IGFBP3, IGFBP5, and IGFBP7 mRNA levels all decreased around this time and returned to embryonic levels by d3. In breast muscle, expression of both IGFBP2 and IGFBP4 was reduced after hatch. Circulating insulin-like growth factor IGF1 and IGF2 levels did not change between hatch and d21. These data suggest that post-hatch IGF effects are likely modulated by target tissue IGFR1 and IGFBP expression rather than changes in circulating hormone levels, with promotion or restriction of IGF-receptor binding regulating growth. Downregulation of several IGFBPs synthesized in the liver may facilitate the metabolic transition from utilizing yolk lipids to dietary carbohydrates. Several IGFBPs produced in breast muscle appear to have growth-promotive effects during embryogenesis but restrict growth of this tissue after hatch, as their post-hatch downregulation could facilitate local IGF signaling. These developmental gene expression patterns suggest that somatotropic hormonal signaling regulating growth and muscle accretion might be controlled through differential actions of IGFBPs and provide a basis for future functional studies.

Insulin-like Growth Factor-Binding Protein 2 in Severe Aortic Valve Stenosis and Pulmonary Hypertension: A Gender-Based Perspective.

Severe aortic valve stenosis (AS) and pulmonary hypertension (PH) are life-threatening cardiovascular conditions, necessitating early detection and intervention. Recent studies have explored the role of Insulin-like Growth Factor-Binding Protein 2 (IGF-BP2) in cardiovascular pathophysiology. Understanding its involvement may offer novel insights into disease mechanisms and therapeutic targets for these conditions. A total of 102 patients (46 female, 56 male) with severe AS undergoing a transcatheter aortic valve replacement (TAVR) in a single-center study were classified using echocardiography tests to determine systolic pulmonary artery pressure (sPAP) and the presence (sPAP ≥ 40 mmHg) or absence (sPAP < 40 mmHg) of PH. Additionally, serial laboratory determinations of IGF-BP2 before, and at 24 h, 96 h, and 3 months after intervention were conducted in all study participants. Considering the entire cohort, patients with PH had significant and continuously higher serum IGF-BP2 concentrations over time than patients without PH. After subdivision by sex, it could be demonstrated that the above-mentioned results were only verifiable in males, but not in females. In the male patients, baseline IGF-BP2 levels before the TAVR was an isolated risk factor for premature death after intervention and at 1, 3, and 5 years post-intervention. The same was valid for the combination of male and echocardiographically established PH patients. The predictive role of IGF-BP2 in severe AS and concurrent PH remains unknown. A more profound comprehension of IGF-BP2 mechanisms, particularly in males, could facilitate the earlier consideration of the TAVR as a more effective and successful treatment strategy.

N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer.

N6-methyladenosine (m6A) methylation modification exists in Epstein-Barr virus (EBV) primary infection, latency, and lytic reactivation. It also modifies EBV latent genes and lytic genes. EBV-associated gastric cancer (EBVaGC) is a distinctive molecular subtype of GC. We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC. To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC. First, The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC (EBVnGC). Second, we identified Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment of m6A-related differentially expressed genes. We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment (TME). Finally, cell counting kit-8 cell proliferation test, transwell test, and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1 (IGFBP1) in EBVaGC cell lines. m6A methylation regulators were involved in the occurrence and development of EBVaGC. Compared with EBVnGC, the expression levels of m6A methylation regulators Wilms tumor 1-associated protein, RNA binding motif protein 15B, CBL proto-oncogene like 1, leucine rich pentatricopeptide repeat containing, heterogeneous nuclear ribonucleoprotein A2B1, IGFBP1, and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC (P < 0.05). The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher (P = 0.046). GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC. Compared with EBVnGC, the infiltration of activated CD4+ T cells, activated CD8+ T cells, monocytes, activated dendritic cells, and plasmacytoid dendritic cells were significantly upregulated in EBVaGC (P < 0.001). In EBVaGC, the expression level of proinflammatory factors interleukin (IL)-17, IL-21, and interferon-γ and immunosuppressive factor IL-10 were significantly increased (P < 0.05). In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line (SNU719) than in an EBVnGC cell line (AGS) (P < 0.05). IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719. Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS. m6A regulators could remodel the TME of EBVaGC, which is classified as an immune-inflamed phenotype and referred to as a "hot" tumor. Among these regulators, we demonstrated that IGFBP1 affected proliferation, migration, and apoptosis.

Serum IGFBP5 as a predictor of major adverse cardiac events in patients with acute myocardial infarction

BackgroundAcute myocardial infarction (AMI) is a serious condition with high mortality rates. Early risk stratification is of significant importance to assess the prognosis. Insulin-like growth factor-binding protein 5 (IGFBP5) levels in AMI patients and its potential as a prognosis biomarker were unclear. ObjectiveTo investigate serum IGFBP5 levels in AMI and its prognostic value for short-term major adverse cardiovascular events (MACE). MethodsWe collected serum IGFBP5 levels from 200 patients with new-onset AMI and 71 coronary heart disease (CAD) patients without AMI. Linear regression was used to analyze the relationship between IGFBP5 and baseline variables. AMI patients were followed up, and the risk of major adverse cardiovascular events (MACE) was assessed using Kaplan-Meier curve, multivariate Cox models and restricted cubic spline (RCS) analysis. ResultsDuring a median follow-up of 217 days, 40 patients developed MACE. Serum IGFBP5 was associated with serum cardiac troponin T (cTnT) and C-reactive protein (CRP) (P = 0.013 and P = 0.013). In multivariable survival analyses, higher IGFBP5 was associated with an increased risk of MACE [HR = 1.183, 95%CI (1.104, 1.268), P < 0.001)]. There was a positive and linear association between IGFBP5 levels and the occurrence of MACE (P for nonlinearity = 0.283). The positive association between IGFBP5 and MACE risk consist across subgroups characterized by demographics and comorbidities. ConclusionSerum IGFBP5 was highly expressed in patients with AMI and positively associated with the short-term risk of MACE. Circulating IGFBP5 may be a diagnostic and prognostic indicator for AMI, and further studies with larger sample and longer follow-up are warranted.

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.

Preoperative Plasma Insulin-Like Growth Factor-I and Its Binding Proteins-Based Risk Stratification of Patients Treated With Radical Nephroureterectomy for Upper Tract Urothelial Carcinoma

IntroductionWe evaluate the predictive and prognostic value of insulin-like growth factor-I (IGF-1), IGF binding protein-2 (IGFBP-2) and -3 (IGFBP-3) in patients treated with radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC). MethodsThis is a retrospective analysis of a multi-institutional database comprising 753 patients who underwent RNU for UTUC and had a preoperative plasma available. Logistic and Cox regression analyses were performed. The discriminative ability and clinical utility of the models was calculated using the lasso regression test, area under receiver operating characteristics curves, C-index, and decision curve analysis (DCA). ResultsLower preoperative plasma levels of IGFBP-2 and -3 independently correlated with increased risks of lymph node metastasis, pT3/4 disease, nonorgan confined disease, and worse recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) (all P ≤ .004). The addition of both IGFBP-2 and -3 to a postoperative multivariable model, that included standard clinicopathologic characteristics, improved the model's concordance index by 10%, 9%, and 8% for RFS, CSS, and OS, respectively. On DCA, addition of both IGFBP-2 and -3 to base models improved their performance for RFS, CSS, and OS by a statistically and clinically significant margin. Plasma IGF-1 was not associated with any of outcomes. ConclusionsWe confirmed that a lower plasma levels of IGFBP-2 and -3 both are independent and clinically significant predictors of adverse pathological features and survival outcomes in UTUC patients treated with RNU. These findings might help guide the clinical decision-making regarding perioperative systemic therapy and follow-up scheduling.

IGFBP2 induces podocyte apoptosis promoted by mitochondrial damage via integrin α5/FAK in diabetic kidney disease.

Podocyte apoptosis or loss is the pivotal pathological characteristic of diabetic kidney disease (DKD). Insulin-like growth factor-binding protein 2 (IGFBP2) have a proinflammatory and proapoptotic effect on diseases. Previous studies have shown that serum IGFBP2 level significantly increased in DKD patients, but the precise mechanisms remain unclear. Here, we found that IGFBP2 levels obviously increased under a diabetic state and high glucose stimuli. Deficiency of IGFBP2 attenuated the urine protein, renal pathological injury and glomeruli hypertrophy of DKD mice induced by STZ, and knockdown or deletion of IGFBP2 alleviated podocytes apoptosis induced by high concentration of glucose or in DKD mouse. Furthermore, IGFBP2 facilitated apoptosis, which was characterized by increase in inflammation and oxidative stress, by binding with integrin α5 (ITGA5) of podocytes, and then activating the phosphorylation of focal adhesion kinase (FAK)-mediated mitochondrial injury, including membrane potential decreasing, ROS production increasing. Moreover, ITGA5 knockdown or FAK inhibition attenuated the podocyte apoptosis caused by high glucose or IGFBP2 overexpression. Taken together, these findings unveiled the insight mechanism that IGFBP2 increased podocyte apoptosis by mitochondrial injury via ITGA5/FAK phosphorylation pathway in DKD progression, and provided the potential therapeutic strategies for diabetic kidney disease.

#1211 IGFBP-5/TGF-β1-mediated cell crosstalk between endothelia and tubular epithelia promotes renal fibrosis

Abstract Background and Aims Renal fibrosis is a common pathophysiological characteristic of chronic kidney disease (CKD) for which there is no effective treatment. The mechanism of renal fibrosis is complicated and remains unclear. Our previous study revealed that Insulin-like growth factor binding protein 5 (IGFBP-5) induces glycolytic activation in ECs and ultimately aggravates renal inflammation in diabetic kidney disease (DKD). This study aims to discover the relationship between IGFBP-5 and renal fibrosis. Method HK-2 and HUVEC cells were included in this study. UUO and ANN model were obstructed by Wild-type, IGFBP-5−/− and IGFBP-5flox/flox, cre mice. IGFBP-5, TGF-β and fibrosis makers were detected to explore the mechanism of IGFBP-5 in fibrosis. Results We found that the serum IGFBP-5 levels were significantly increased in CKD, that IGFBP-5 was dominantly localized in vascular endothelial cells (ECs) of kidney tissue, and that IGFBP-5 deficiency relieved renal fibrosis in CKD model mice. In vitro experiments indicated that IGFBP-5 exacerbated the fibrosis phenotypic alteration of tubular epithelial cells (TECs) by the TGF-β1/p-Smad3 signaling pathway. In turn, TGF-β1 could facilitate the synthesis of IGFBP-5 in ECs. The crosstalk between TECs and ECs mediated by IGFBP-5 and TGF-β1 was confirmed in a coculture system and endothelial-specific IGFBP-5-deficient mice. Conclusion Renal fibrosis is exacerbated by TEC-EC cellular crosstalk through the feedback loop consisting of IGFBP-5 and TGF-β1. These findings suggest that IGFBP-5 may be a new pathogenic factor in renal fibrosis and a potential new therapeutic target in CKD.

Plasma IGFBP-3 and IGFBP-5 levels are decreased during acute manic episodes in bipolar disorder patients.

Introduction: Bipolar disorder (BD) is a recurrent and disabling psychiatric disorder related to low-grade peripheral inflammation and altered levels of the members of the insulin-like growth factor (IGF) family. The aim of this study was to evaluate the plasma levels of IGF-2, insulin-like growth factor-binding protein 1 (IGFBP-1), IGFBP-3, IGFBP-5, IGFBP-7, and inflammatory markers such as tumor necrosis factor α (TNF-α), monocyte chemoattractant protein 1 (MCP-1), and macrophage inflammatory protein 1β (MIP-1β). Methods: We used the Young Mania Rating Scale (YMRS) to determine the severity of the symptomatology, while proteins were measured by enzyme-linked immunosorbent assay (ELISA). We included 20 patients with BD who suffered a manic episode and 20 controls. Some BD patients (n = 10) were evaluated after a period (17 ± 8days) of pharmacological treatment. Results: No statistical difference was found in IGF-2, IGFBP-1, IGFBP-7, TNF-α, and MIP-1β levels. However, IGFBP-3 and IGFBP-5 levels were found to be statistically decreased in BD patients. Conversely, the MCP-1 level was significantly increased in BD patients, but their levels were normalized after treatment. Intriguingly, only IGFBP-1 levels were significantly decreased after treatment. No significant correlation was found between the YMRS and any of the proteins studied either before or after treatment or between IGF proteins and inflammatory markers. Discussion: To some extent, IGFBP-3 and IGFBP-5 might be further explored as potential indicators of treatment responsiveness or diagnosis biomarkers in BD.

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-β-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

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. To identify associations of growth hormone mediators with glycemic failure, beta cell function, and insulin sensitivity in youth-onset T2D. 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. Plasma insulin-like growth factor-1 (IGF-1), growth hormone receptor (GHR), and insulin-like growth factor binding protein 1 (IGFBP-1). 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). 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 (β [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 (β [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 (β [SE], 431 [156]; P = .007). 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. ClinicalTrials.gov Identifier: NCT00081328.

Associations Between Hypertension, Angiotensin-Converting Enzyme Inhibitors, and Physical Performance in Very Old Adults: Results from the ilSIRENTE Study

BackgroundResults regarding the associations between hypertension-related parameters and physical performance in older adults are conflicting. A possible explanation for these divergent results is that investigations may not have adjusted their analyses according to the use of angiotensin-converting enzyme inhibitors (ACEIs).ObjectivesTo examine the associations between hypertension-related parameters, ACEI use, and a set of physical performance tests in very old adults.DesignCross-sectional study from the ilSIRENTE database.SettingMountain community of the Sirente geographic area (L’Aquila, Abruzzo, Italy).ParticipantsAll persons born in the Sirente area (13 municipalities) before 1 January 1924 and living in that region at the time of study were identified and invited to participate. The final sample included 364 older adults (mean age: 85.8 ± standard deviation [SD] 4.8).MeasurementsPhysical performance was assessed using isometric handgrip strength (IHG), walking speed (WS) at normal and fast pace, 5-time sit-to-stand test (5STS), and muscle power measures. Blood pressure (BP) was measured after 20 to 40 min of rest, while participants sat in an upright position. Drugs were coded according to the Anatomical Therapeutic and Chemical codes. ACEIs were categorized in centrally (ACEI-c) and peripherally (ACEI-p) acting. Blood inflammatory markers, free insulin-like growth factor 1 (IGF-1), and IGF-binding protein 3 (IGFBP-3) were assayed.ResultsResults indicated that 5STS test was significantly and negatively associated with diastolic BP values. However, significance was lost when results were adjusted for ACEI use. Participants on ACEIs were more likely to have greater specific muscle power and higher blood levels of IGFBP-3 than non-ACEI users. When participants were categorized according to ACEI subtypes, those on ACEI-p had higher blood IGF-1 levels compared with ACEI-c users.ConclusionsThe main findings of the present study indicate that ACEI use might influence the association between hypertension-related parameters and neuromuscular parameters in very old adults. Such results may possibly be linked to the effects of ACEI-p on the IGF-1 pathway.

Upregulation of Anti-Angiogenic miR-106b-3p Correlates Negatively with IGF-1 and Vascular Health Parameters in a Model of Subclinical Cardiovascular Disease: Study with Metformin Therapy.

Well-controlled type 1 diabetes mellitus (T1DM) is regarded as a model of subclinical cardiovascular disease (CVD), characterized by inflammation and adverse vascular health. However, the underlying mechanisms are not fully understood. We investigated insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) levels, their correlation to miR-106b-3p expression in a subclinical CVD model, and the cardioprotective effect of metformin. A total of 20 controls and 29 well-controlled T1DM subjects were studied. Plasma IGF-1, IGFBP-3 levels, and miR-106b-3p expression in colony-forming unit-Hills were analyzed and compared with vascular markers. miR-106b-3p was upregulated in T1DM (p < 0.05) and negatively correlated with pro-angiogenic markers CD34+/100-lymphocytes (p < 0.05) and IGF-1 (p < 0.05). IGF-1 was downregulated in T1DM (p < 0.01), which was associated with increased inflammatory markers TNF-α, CRP, and IL-10 and reduced CD34+/100-lymphocytes. IGFBP-3 had no significant results. Metformin had no effect on IGF-1 but significantly reduced miR-106b-3p (p < 0.0001). An Ingenuity Pathway analysis predicted miR-106b-3p to inhibit PDGFA, PIK3CG, GDNF, and ADAMTS13, which activated CVD. Metformin was predicted to be cardioprotective by inhibiting miR-106b-3p. In conclusion: Subclinical CVD is characterized by a cardio-adverse profile of low IGF-1 and upregulated miR-106b-3p. We demonstrated that the cardioprotective effect of metformin may be via downregulation of upregulated miR-106b-3p and its effect on downstream targets.

Evaluating the effect of recombinant human growth hormone treatment on sleep-related breathing disorders in toddlers with Prader–Willi syndrome: a one-year retrospective cohort study

BackgroundRecombinant human growth hormone (rhGH) therapy is beneficial for children with Prader–Willi syndrome (PWS) in improving short stature and metabolism, but the effect of early rhGH treatment on respiratory and sleep parameters for PWS children under three years old remains elusive. Thus, this study aimed to investigate the impact of rhGH treatment on sleep-related breathing disorders (SRBDs) for toddlers with PWS.MethodsA total of 17 age-matched PWS patients receiving rhGH treatment (rhGH group) and 17 control individuals not receiving rhGH treatment (non-rhGH group) were recruited for this study between October 2018 and January 2023. Data related to polysomnography-polygraphy (PSG) and serum levels of insulin-like growth factor (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) were collected.ResultsThe mean age in the rhGH group was 20.76 ± 9.22 months, which was comparable to that of the non-rhGH group (25.23 ± 13.81 months). The demographic and anthropometric parameters were similar across the two groups after 52 weeks of treatment. Administration of rhGH to toddlers did not exert adverse effects on the obstructive apnea–hypopnea index (OAHI), central apnea index (CAI), oxygen desaturation index (ODI), mean percutaneous oxygen saturation (SpO2), lowest SpO2, duration when SpO2 is lower than 90%, or proportion of the patients with SpO2 lower than 90%. Furthermore, the increased IGF-1 z-score and IGFBP-3 level did not worsen SRBDs.ConclusionTreatment with rhGH for 52 weeks on young toddlers with PWS showed no deleterious effects on SRBDs. This shed more light on the importance of initiating rhGH therapy early in PWS patients.

An exploratory study of clinical factors associated with IGF-1 and IGFBP-3 in preterm infants.

Despite advances in parenteral nutrition, postnatal growth failure in very low birthweight (VLBW) preterm infants is common and associated with chronic health problems. Insulin-like growth factor 1 (IGF-1) is positively associated with improved infant growth, but factors which promote IGF-1 levels in this population have not been clearly identified. The objective of this study was to explore early factors that influence IGF-1 in VLBW preterm infants. VLBW infants were enrolled into a prospective, randomized controlled nutrition trial (N = 87). Outcome measures included IGF-1 and IGFBP-3 levels measured at 35 weeks PMA. Linear regression analyses tested the relationships between candidate clinical predictors and levels of IGF-1 and IGFBP-3. Higher protein intake, longer duration of parenteral nutrition, and lower IGFBP-3 levels at 1 week of life were associated with lower IGF-1 levels at 35 weeks PMA. Neither early markers of insulin resistance nor degree of illness were associated with IGF-1 levels at 35 weeks PMA. Optimization of early nutrient intake, and attention to route of delivery, may have a lasting influence on IGF-1/IGFBP-3, and in turn, long-term health outcomes. In very low birthweight preterm infants, early protein intake, duration of parenteral nutrition, and insulin-like growth factor binding protein 3 (IGFBP-3) levels at 1 week of life are positively associated with insulin-like growth factor 1 (IGF-1) levels at 35 weeks postmenstrual age. Data from this study highlight the influence of early nutrition on components of the endocrine axis in preterm infants. Strategies aimed at early initiation of enteral nutrition, as well as optimizing composition of parenteral nutrition, may bolster hormones involved in promoting preterm infant growth.