MIC-1, a novel macrophage inhibitory cytokine, is a divergent member of the TGF-beta superfamily

HIIT may ameliorate inter-organ crosstalk between liver and hypothalamus of HFD-induced MAFLD rats; A two-phase study to investigate the effect of exercise intensity as a stressor

Previous studies demonstrate that GDF15 and its related signaling activators may be affected by exercise training, leading to the suppression of inflammatory factors and the promotion of immune-metabolic balance. Therefore, the purpose of the study was to evaluate the effect of high-intensity interval training (HIIT) on amelioration of inter-organ crosstalk between liver and hypothalamus of the high-fat diet (HFD)-induced metabolic dysfunction-associated fatty liver disease (MAFLD) rats in a two-phase study. In this regard, rats were initially divided into two groups, the normal diet-inactive (NS) and the HFD groups. HFD course lasted 12 weeks to induce MAFLD in the latter group. After ensuring the induction of MAFLD, 25 rats were divided into three groups: the HFD-inactive group (HS), the HFD-HIIT group (HH), as well as the HFD-aerobic group (HA). The training interventions were consistently applied over a period of eight weeks, five days a week, with each session lasting 40-60 min, and the duration of the whole research was 21 weeks. The results of this study displayed that HIIT intervention promotes hypothalamic Gdf15 gene expression and there were similar alterations in genes expression of Foxo1 and Akt2. Moreover, our results confirmed that HIIT ameliorated hypothalamic NFKB gene expression and there was a similar trend in genes expression of Tnfa and Il1b following both HIIT as well as aerobic training protocols. Taking these findings together, it is concluded that interventions, particularly exercise training, uniquely contribute to the reduction of hypothalamic-associated inflammatory responses that result in prolonged and chronic increases in GDF15.

Age-Associated Increase in Growth Differentiation Factor 15 Levels Correlates With Central Arterial Stiffness and Predicts All-Cause Mortality in a Sardinian Population Cohort

BACKGROUND

Growth differentiation factor 15 (GDF-15) levels are emerging as a candidate biomarker of aging. The present study aimed to: (1) characterize the association of GDF-15 with the continuum of arterial stiffening, assessed as carotid-femoral pulse wave velocity, as age increases; (2) determine the predictive role of serum GDF-15 levels on mortality; and (3) identify genetic determinants of serum GDF-15 levels.

METHODS AND RESULTS

Serum levels of GDF-15 and established cardiovascular risk factors, including pulse wave velocity, were assessed in a large (4736 individual) Sardinian population. Serum levels of GDF-15, which can be reliably measured repeatedly over time, increase with age; are associated with a stiffer aorta; "mediate" a large proportion of the age-associated increase in arterial stiffness; pose risks because of their association with greater mortality; and are significantly associated with the variant rs11549407, which causes thalassemia major in homozygosity.

CONCLUSIONS

Because of its consistent ability to predict functional and clinical outcomes, including all-cause mortality, we conclude that GDF-15 serum levels serve as a robust biomarker for the continuum from health to the emergence of clinical disease during aging and, subsequently, to the likelihood of mortality.

Hepatic estrogen-related receptor gamma is a key regulator of GDF15 production in acute and chronic liver injury

AIMS

Growth differentiation factor 15 (GDF15) is a stress-induced hepatokine with emerging roles in liver injury. Estrogen-related receptor γ (ERRγ), a nuclear receptor regulating mitochondrial function and metabolic stress, has also been implicated in various liver injury conditions. However, the regulatory interplay between ERRγ and GDF15 remains unclear. This study investigates the molecular mechanisms underlying GDF15 expression and secretion in the liver, focusing on the role of ERRγ during acute and chronic liver injury.

MATERIALS AND METHODS

Wild-type and hepatocyte-specific ERRγ knockout (ERRγ-LKO) mice were administered with a single dose of carbon tetrachloride (CCl4) or fed an alcohol-containing diet for 4 weeks to establish acute or chronic liver injury models, respectively. ERRγ was overexpressed through an adenoviral construct (Ad-ERRγ). The ERRγ-specific inverse agonist GSK5182 was employed to inhibit the transactivation of ERRγ. The luciferase reporter assays were used to assess the binding of ERRγ protein to the regulatory region of GDF15 gene.

KEY FINDINGS

Hepatic ERRγ and GDF15 gene expression, and GDF15 protein secretion were significantly elevated in both acute and chronic liver injury. Adenovirus-mediated overexpression of ERRγ is sufficient to substantially increase hepatic GDF15 expression and secretion. Genetic ablation of ERRγ expression or pharmacological inhibition of ERRγ transactivation substantially inhibited the upregulation of hepatic GDF15 expression and production in both acute and chronic liver injury. Furthermore, reporter assays showed that ERRγ, but not ERRα or ERRβ, directly binds to and activates the GDF15 gene promoter.

SIGNIFICANCE

Our findings highlight the crucial role of ERRγ in transcriptional regulation of GDF15 gene expression and production in response to liver damage. Understanding the regulatory mechanisms of GDF15 expression could lead to new therapeutic targets for protecting the liver from various types of injuries and associated diseases.

Growth differentiation factor 15 as a potential diagnostic biomarker for rheumatoid arthritis : a systematic review

Aims

This systematic review aimed to investigate the association between growth differentiation factor 15 (GDF-15) and rheumatoid arthritis (RA) disease activity, explore the differences at the genetic level, and evaluate the value of GDF-15 in diagnosing RA.

Methods

A comprehensive literature search was conducted using PubMed, Web of Science, Cochrane Library, and Embase on 23 August 2023. Methodological quality was independently assessed by using the Agency for Healthcare Research and Quality scale. The primary parameters analyzed were the serum GDF-15 concentration, disease activity, and diagnostic sensitivity and specificity.

Results

A total of 469 documents were retrieved, and five clinical studies were ultimately included. In the included studies, GDF-15 serum levels were found to be notably greater in RA patients than in healthy individuals, and these levels exhibited a positive correlation with disease severity. Furthermore, increased GDF-15 serum levels were associated with specific gene variations in RA patients, but varied according to ethnicity. In two included studies, GDF-15 showed high diagnostic sensitivity and specificity for highly active RA, demonstrating its utility as a diagnostic biomarker of RA.

Conclusion

GDF-15 expression is increased in RA patients and is associated with disease activity; thus, GDF-15 is potentially an effective diagnostic biomarker for RA. However, additional high-quality studies, especially randomized controlled trials and cohort studies with follow-up data, are needed to assess the role of GDF-15 in RA.

GDF15 Analogues Acting as GFRAL Ligands

Growth differentiation factor 15 (GDF15) is a TGF-β superfamily member involved in diverse physiological and pathological processes. It is expressed in various tissues and its circulating levels rise during exercise, aging, pregnancy, and conditions such as cancer, cardiovascular disease, and infections. The biological activities of GDF15, including anorexia and cachexia, are primarily mediated through the GFRAL receptor, localized in the brainstem and functioning via RET co-receptor recruitment. This signaling is crucial for energy homeostasis and nausea induction. Recent studies suggest a broader GFRAL distribution, potentially explaining GDF15's distinct roles. These findings sparked interest in leveraging GDF15-GFRAL pathways for therapeutic development. Two primary strategies include GDF15 analogues as GFRAL agonists for obesity treatment and GDF15-derived peptides as antagonists to counteract cancer-induced cachexia and related disorders. This review highlights advancements in understanding GDF15-GFRAL signaling and its implications, summarizing bioactive GDF15-derived molecules, their pharmacological applications, and offering insights into novel treatment avenues for GDF15-associated conditions.

Desensitizing Effect of Intra-Tumoral GDF-15 on Immunotherapy in Patients With Advanced Non-Small Cell Lung Cancer

BACKGROUND

Serum growth/differentiation factor 15 (GDF-15) suppresses anti-tumor immunity and predicts prognosis in several malignancies. Elevated GDF-15 levels are linked to cancer cachexia, characterized by weight loss and systemic inflammation, adversely affecting patient outcomes and therapy response. However, serum GDF-15 is not always derived from tumor tissues but also from multiple organs. Therefore, we evaluated whether intra-tumoral GDF-15 could be used as a biomarker for immunotherapy and its potential association with cancer cachexia.

METHOD

We retrospectively evaluated patients with advanced non-small cell lung cancer (NSCLC) who underwent treatment with programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) inhibitors at the Shizuoka Cancer Center between 2017 and 2021. Patients with histologically confirmed NSCLC (stage III-IV or postoperative recurrence) who had undergone biopsy or surgery within 6 months prior to initiating immunotherapy were included. Expression of tumor-derived GDF-15 was evaluated using immunohistochemical staining of archival biopsy and surgical specimens. We analyzed the correlation between intra-tumoral GDF-15 expression and the incidence of cancer cachexia, as well as its impact on progression-free survival (PFS) and overall survival (OS).

RESULT

In 6 of 35 cases, tumor cells highly expressed GDF-15. Patients with high intra-tumoral GDF-15 expression had a higher incidence of cancer cachexia (100% vs. 41.4%, p < 0.05), shorter PFS (3.4 vs. 13.4 months, p < 0.05), and shorter OS (9.5 vs. 26.5 months, p < 0.05) than those with low intra-tumoral GDF-15 expression.

CONCLUSION

Intra-tumoral GDF-15 expression may predict the presence of cancer cachexia and the efficacy of PD-1/PD-L1 inhibitors in patients with advanced non-small cell lung cancer.

Growth differentiation factor 15: a promising biomarker in oral cancer

Growth differentiation factor 15 (GDF-15), a cytokine within the transforming growth factor-β superfamily, is involved in various malignancies, with implications in oral squamous cell carcinoma (OSCC). Elevated GDF-15 levels are correlated with unfavorable prognosis, tumor progression, and chemotherapy resistance, and the protein has been identified as a potential diagnostic and prognostic biomarker for OSCC. Personalized treatment strategies based on GDF-15 expression could improve treatment outcomes.

The association between serum growth differentiation factor 15 and insulin resistance in women diagnosed with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is strongly associated with metabolic abnormalities, with 50-70% of patients exhibiting insulin resistance (IR), which significantly impacts the reproductive health of women in their reproductive years. Growth differentiation factor 15 (GDF15), a hormone responsive to nutritional stress, has been implicated in several diseases. This study sought to clarify the relationship between GDF15 levels and IR condition in PCOS patients. Based on the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), patients were categorized into an IR-PCOS group (n = 124) and a non-insulin-resistant group (non-IR-PCOS group, n = 109). Fasting blood samples were collected to measure GDF15 concentrations. To assess metabolic complications in relation to GDF15 levels, patients were also classified into high and normal GDF15 groups. Serum GDF15 levels were significantly higher in IR-PCOS patients (median 772.94 pg/ml) compared to non-IR-PCOS patients (median 575.80 pg/ml, P < 0.05). The high GDF15 group showed more severe metabolic and lipid abnormalities than the normal GDF15 group. Spearman correlation analysis revealed a correlation between increased GDF15 levels and impaired glucose metabolism. Logistic regression analysis identified GDF15, HDL-C, and prolactin as risk factors for IR in PCOS, and the fully adjusted regression coefficient for GDF15 levels and IR prevalence was 4.490 (95% CI 1.541 to 13.088). Restricted cubic spline analysis confirmed a positive association between GDF15 levels and IR within a specific range. The combined predictive probability of GDF15, prolactin, and HDL-C for IR was 0.763 (95% CI 0.701 to 0.826) according to ROC analysis. Elevated GDF15 levels may be associated with IR in PCOS patients, suggesting a potential role for GDF15 in the pathophysiology of IR in this condition.

The heterogeneity of cirrhosis - systemically assessed endotypes described by fibrosis, apoptosis, and immunoregulatory-related biomarkers

BACKGROUND

Given the heterogeneity of advanced chronic liver disease, assessing disease activity-related biomarkers could aid in classifying cirrhosis endotypes for better patient monitoring and treatment selection.

AIM

To investigate cirrhosis endotypes described by disease activity biomarkers related to fibrogenesis, immune cell activity, apoptosis, and systemic inflammation.

METHODS

The study included plasma EDTA samples from 106 participants with mild, moderate, and severe liver cirrhosis undergoing hepatic venous pressure gradient (HVPG) measurements and 39 healthy control participants. The biomarkers nordicPROC3™ (fibrogenesis), GDF-15, CK18 M30 (apoptosis), CRP (systemic inflammation), nordicCPa9-HNE™ (neutrophil activity), and nordicVICM™ (macrophage activity) were measured.

RESULTS

PROC3, GDF-15, CK18 M30, and CRP increased with cirrhosis severity (p < 0.05-p < 0.0001) and the degree of portal hypertension (p < 0.05-p < 0.01). CPa9-HNE decreased from mild to moderate and mild to severe cirrhosis (p < 0.01-0.0001) and correlated with HVPG (r=-0.53, p < 0.0001). VICM decreased from mild to severe cirrhosis (p < 0.01). A heatmap clustered analysis revealed four potential cirrhosis endotypes, reflecting underlying biological processes.

CONCLUSION

Assessing markers related to active fibrogenesis, apoptosis, immune cell activity, and systemic inflammation revealed distinct molecular patterns among patients with cirrhosis. These findings suggest the presence of potential disease endotypes that could inform future strategies for patient monitoring, treatment selection, and prognostic assessment in cirrhosis management.

Association of Circulating GDF-15 with Fetal Growth in Gestational Diabetes

Background/Objectives: Growth differentiation factor-15 (GDF-15) is a component of the transforming growth factor beta (TGF-β) family that may act as regulator of inflammation. A possible protective role of GDF-15 against glucose alterations has been hypothesized. The aim of this pilot study was to evaluate the relationship between a circulating concentration of GDF-15 and metabolic/inflammatory parameters, as well as with adverse perinatal outcomes in patients with gestational diabetes mellitus (GDM). Methods: Twenty-four (n = 24) patients with GDM and n = 29 age-matched pregnant women with normal glucose tolerance (NGT) were recruited at the third trimester of gestation. Clinical and biochemical parameters were collected. Serum levels of GDF-15, small dense low density lipoprotein cholesterol (sdLDL), interleukin 6 (IL-6), a Soluble Urokinase Plasminogen Activator Receptor (su-PAR) were measured by an enzyme-linked immunosorbent assay kit. Fetal ultrasound parameters, maternal, delivery, and perinatal outcomes, were assessed. Results: Serum GDF-15 did not differ between GDM and NGT (p = 0.286). However, in linear regression analysis, a significant negative association was observed between GDF-15 and fetal weight percentile at the third trimester, only in patients with GDM (p = 0.013), even after adjustment for age and pre-pregnancy BMI (p = 0.029). GDF-15 positively associated with IL-6, adjusting for pre-pregnancy BMI (p = 0.047). Pregnant women with adverse perinatal outcomes had higher levels of GDF-15 (p = 0.043). In the regression model, higher levels of GDF-15 were associated with an increased likelihood of adverse perinatal outcomes after adjustment for age and pre-pregnancy BMI (p = 0.044). Conclusions: Besides its action as regulator of inflammation, GDF-15 might have a possible protective role against hyperglycemia-related excessive fetal growth in GDM. GDF-15 circulating levels might also be related to adverse perinatal outcomes.

GDF15 attenuates Parkinson's disease progression via suppressing the activation of cGAS-STING pathway

Growth differentiation Factor 15 (GDF15) plays an important role in the innate immune response. However, whether GDF15 could regulate Parkinson's disease (PD) remains unknown. In this study, we explored the function and underlying molecular mechanisms of GDF15 in PD. The protein and mRNA expressions were examined applying immunofluorescence staining, Western blot and qRT-PCR. Ferrous iron content was also assessed using an iron assay kit. The effect of GDF15 knockdown on mitochondrial membrane potential, ROS level, intracellular Fe2+ level and mitochondrial permeability transition pore opening in PD cell model was evaluated utilizing JC-1 staining, DCFH-DA fluorescent probe, ferro orange staining and calcein AM + Co2+ quencher staining. GDF15 was upregulated in the substantia nigra and striatum of PD mice and MPP+-caused SH-SY5Y cells. GDF15 knockdown aggravated parkinsonian symptoms in PD mice. Moreover, GDF15 knockdown aggravated dopamine neuronal damage, and promoted ferroptosis and inflammation in PD in vivo and in vitro. Besides, GDF15 knockdown could activate cGAS-STING pathway in vivo and in vitro PD model. We also found that the treatment of RU.521 could reverse the effect of GDF15 knockdown on dopamine neuronal damage, inflammation and ferroptosis in MPP+-induced SH-SY5Y cells. Similarly, the treatment of SR-717 could reverse the effect of GDF15 overexpression on dopamine neuronal damage, inflammation and ferroptosis in MPP+-induced SH-SY5Y cells. The results of this study demonstrated that GDF15 could attenuate dopamine neuronal damage, and inhibit ferroptosis and inflammation in PD via suppressing cGAS-STING pathway activation.

The effect of exercise on GDF-15 levels in individuals with prediabetes: A randomized controlled trial

AIMS

Growth differentiation factor-15 (GDF-15) is an inflammatory cytokine that increases in prediabetes and is known for its anorexigenic effects. This study aims to evaluate the effects of a 12-week exercise program on GDF-15 in individuals with prediabetes.

MATERIALS AND METHODS

In this multicenter, parallel-group, randomized-controlled trial, 64 patients aged 18-60 diagnosed with prediabetes were randomized in a 1:1 ratio into the exercise group (E) and the control group (C). Additionally, 32 patients who were planned to start metformin were included in the metformin group (M). Participants in the exercise group engaged in aerobic exercise at 50-70% of their maximum heart rate for 60 min, 3 days a week. Serum GDF-15 levels were evaluated at the beginning and the end of the 12th week.

RESULTS

The mean age of the 91 participants who completed the study was 46.13 ± 8.52 years, and 23.1% were male. Basal GDF-15 levels were similar among the groups (E = 668.6 ± 415.1, C = 651.8 ± 352.5, M = 603.6 ± 387.2, P = 0.47). At the 12th week, GDF-15 levels were lower in the E compared to the C, while higher in the M compared to the C (E = 383.1 ± 215.6, C = 556.4 ± 285.6, M = 810.8 ± 498.0, P < 0.001). In inter-group comparisons, no significant change was observed in the C between the 0th and 12th weeks, while GDF-15 decreased in the E (P < 0.001) and increased in the M (P < 0.001).

CONCLUSIONS

It was determined that in individuals with prediabetes, GDF-15, which serves both as a biomarker of metabolic disorder and has a negative regulatory effect on appetite, decreased with 12 weeks of aerobic exercise and increased with metformin administration.

Circulating Growth Differentiation Factor 15 (GDF15) in Paediatric Disease: A Systematic Review

BACKGROUND

Growth Differentiation Factor 15 (GDF15), a nonspecific inflammatory marker and member of the TGF-β superfamily, has a well-established role in both inflammation and metabolic modulation, but lacks a comprehensive paediatric literature review. In several adult disease states, including cancer cachexia and pregnancy, circulation and expression of GDF15 has been of clinical and scientific interest, but little published paediatric data exists. As such, we aim to summarize existing paediatric studies.

METHODS

This review follows the PRISMA-ScR guidelines for reporting and aims to summarize existing paediatric studies including GDF15, describe disease entities in which GDF15 has been investigated including existing reference ranges, and identify literature gaps to present future clinical and research direction. Our search strategy queried Ovid MEDLINE, Ovid Embase, Cochrane Library and Scopus databases to find original scientific articles measuring GDF15 from birth through children up to age 18. Data relating to study participant demographic and disease pathology, GDF15 measurement methods and clinical outcomes of interest were extracted.

RESULTS

Sixty-two studies were included, classified as cardiac, endocrine, mitochondrial, hematologic, neonatal, oncologic, infectious, rheumatologic, renal, neurologic or healthy. While several entities demonstrated elevated GDF15, the highest median GDF15 levels were observed in cardiac arrest 7089 pg/mL (interquartile range 3805-13 306) and mitochondrial diseases 4640 pg/mL (1896-14 064). In certain conditions, including cardiac stress, polycystic ovarian syndrome (PCOS), Kawasaki Disease (KD) and certain mitochondrial myopathies GDF15 can normalize with disease treatment or resolution. Of healthy children studied, GDF15 levels were highest in healthy neonates and followed a predictable pattern, decreasing over time. Mean and standard deviation values of GDF15 in healthy children were 343.8 ± 221.0 pg/mL, with a range of 90-1134 pg/mL for study averages.

CONCLUSIONS

Circulating GDF15 has been studied in a variety of paediatric diseases. However, variable evaluated outcome measures and GDF15 measurement methodologies prevent generalizability and direct comparison of these published studies. Validating normal GDF15 levels in children with standardized and reproducible methodology will help clarify GDF15's utility as a diagnostic marker of disease, a necessary step to elucidate clinical implications of GDF15 over expression and its potential as a therapeutic target.

Krebs von den Lungen-6 as a biomarker for distinguishing between interstitial lung disease and interstitial lung abnormalities based on computed tomography findings

Background

Krebs von den Lungen-6 (KL-6), predominantly expressed by type II alveolar cells, is linked to the prognosis and severity of interstitial lung disease (ILD). This investigation sought to explore the relationship between KL-6 concentrations and the presence of ILD versus interstitial lung abnormalities (ILA).

Methods

This single-center retrospective study included 147 patients who were suspected of ILD and underwent KL-6 testing between October 2022 and March 2023. Epidemiological and clinical details of the patients, including the outcomes of pulmonary function tests and computed tomography findings, were retrospectively extracted from electronic medical records.

Results

The average age within the cohort was 77.1 years, with 97.3% (143 patients) being male. Notably, the ILA group displayed significantly reduced levels of KL-6 compared to the ILD group (411.6±298.8 vs. 968.8±901.9 U/mL, P<0.001). Utilizing a threshold of 410 U/mL for KL-6, the diagnostic performance yielded an area under the curve (95% CI) of 0.727 (0.605-0.849), demonstrating a sensitivity of 80.8% and a specificity of 64.7%.

Conclusions

Our findings indicate that serum KL-6 concentrations are markedly elevated in patients with clinically recognized and treated ILD compared to those identified with ILA. Furthermore, the association between higher KL-6 levels and reduced forced vital capacity percentage underlines the biomarker's potential in differentiating between ILD requiring intervention and less severe abnormalities.

Comparative Analyses Between Vulnerability Biomarkers of Aging and Health Biomarkers in Middle-Aged and Older Female Adults

Biological aging is normally associated with greater physiological changes which predispose individuals to adverse outcomes. In this way, the evaluation of vulnerability biomarkers and their relationships with other health biomarkers could contribute to the promotion of interventions and the improvement of older adults' quality of life. Thereby, this study aimed to compare vulnerability biomarkers (Growth Differentiation Factor 15 (GDF-15), General Functional Fitness Index (GFFI), and frailty phenotype) and their influence on health markers (blood biochemistry, body composition, and hemodynamic variables) in middle-aged and older female adults. Methods: A cross-sectional observational study was conducted with community-dwelling females aged 54-84 with at least 6 months of experience with physical training. The participants were categorized based on functional fitness, frailty phenotype, and GDF-15 quartiles. The General Functional Fitness Index (GFFI) was assessed using the AAHPERD test battery, while frailty phenotype was determined using Fried's criteria. GDF-15 levels were measured through ELISA. Results: A higher training status (TS) showed better functional fitness and favorable biochemical profiles, including lower total cholesterol (p = 0.006, η2p = 0.253), LDL cholesterol (p = 0.001, η2p = 0.346), triglycerides (p = 0.048, η2p = 0.195), and systolic blood pressure (p = 0.001, η2p = 0.333). Individuals classified as robust (non-frail) had better physical performance and lower total cholesterol (p = 0.002, η2p = 0.306) and LDL cholesterol (p = 0.014, η2p = 0.216) compared to those classified as frail and pre-frail. The GDF-15 quartile did not present differences in health markers between groups. Conclusions: These findings suggest that GFFI may be considered a health biomarker for middle-aged and female older adults while highlighting the need for further research on the role of biomarkers of vulnerability and healthy aging.

Direct triangular comparison of tissue and serum growth differentiation factor 15 with host factors in colorectal cancer

Growth differentiation factor 15 (GDF-15) is a potential biomarker for colorectal cancer (CRC) and is associated with sarcopenia and cachexia. However, its clinical significance in CRC remains unclear. We investigated the clinical significance of GDF-15 in CRC patients by a unique triangular comparison of tissue and preoperative serum GDF-15 levels with host factors. We evaluated 428 tissue and 214 serum samples from 214 CRC patients. We measured tissue and serum levels of GDF-15 and assessed their association with oncological outcomes and host factors. While cancer tissue GDF-15 levels showed no significant associations with clinicopathological factors or survival, preoperative serum GDF-15 levels were significantly correlated with indicators of disease progression, such as advanced T stage and advanced pathological stage. High preoperative serum GDF-15 level was associated with poor disease-free survival and overall survival and was an independent prognostic factor for disease-free survival and overall survival. Significant correlations were observed between preoperative serum GDF-15 levels and host factors, including body mass index, psoas muscle mass index, intramuscular adipose tissue content, and C-reactive protein. In conclusion, preoperative serum GDF-15 reflects host factors such as body composition and inflammation and is a useful marker for the oncological management of CRC patients.

Brown adipose tissue transplantation ameliorates hindlimb ischemic damage in diabetic mice

Peripheral arterial disease (PAD) is a common complication associated with diabetes, which can lead to foot ischemia. The condition is often accompanied by infection and necrosis, ultimately leading to diabetic foot ulcers and the risk of amputation. Brown adipose tissue (BAT) and its secreted cytokines play an essential role in the regulation of glucose homeostasis, the modulation of inflammatory responses, and vascular endothelial cell proliferation. The transplantation of BAT into ischemic regions may offer therapeutic benefits in alleviating the symptoms associated with PAD. A diabetic mouse model was established via intraperitoneal administration of streptozocin. Subsequently, a diabetic lower limb ulcer model was constructed by transection of the femoral artery and ligation of the femoral vein. BAT harvested from the subscapular region of the mouse was employed as an adipose graft. The research utilized Laser Doppler monitoring, Western blot analysis, hematoxylin-eosin (HE) staining, immunofluorescence staining, and enzyme-linked immunosorbent assay (ELISA) to evaluate blood flow recovery in ischemic regions, histopathological changes, angiogenesis and tissue remodeling, inflammatory responses, and M1/M2 macrophage polarization. BAT transplantation significantly enhanced blood flow recovery in ischemic regions of diabetic lower limb ulcer mice while concurrently reducing necrotic tissue. Pathological analyses demonstrate that BAT transplantation mitigates ischemic tissue damage, stimulates angiogenesis, and supports tissue remodeling. Furthermore, the Western blotting, immunofluorescence, and ELISA results revealed that BAT transplantation significantly reduces inflammatory levels in ischemic tissues, increases the expression of angiogenic factors, and promotes the polarization of macrophages from the M1 to the M2 phenotype. The research has demonstrated that BAT transplantation can mitigate ischemic injury in diabetic lower limb ulcer mice, attenuate inflammatory responses, and facilitate the restoration of blood flow. These effects may be linked to alterations in macrophage polarization.

GDF-15 as a biomarker for diagnosis and prognosis of lung cancer: a meta-analysis

Introduction

Due to the tendency of lung cancer to be diagnosed at advanced stages, many patients are not eligible for curative surgery. Identifying early detection and prognosis biomarkers is crucial for improving outcomes. This study explores the potential of Growth Differentiation Factor 15 (GDF-15) as a biomarker for these purposes.

Methods

A thorough review and meta-analysis of literature from PubMed, Embase, the CENTRAL, and the CNKI was performed. We analyzed the diagnostic accuracy of GDF-15, focusing on its sensitivity, specificity, and AUC. Additionally, we investigated the association between three-year overall survival and GDF-15 levels in lung cancer patients. Our analysis included nine studies, encompassing 1296 patients with lung cancer and 1182 healthy controls.

Results

GDF-15 showed high diagnostic performance with a sensitivity of 0.80 (95% Confidence Interval (CI): 0.71-0.87), specificity of 0.92 (95% CI: 0.85-0.96), diagnostic odds ratio of 45 (95% CI: 25-79), and an AUC of 0.93 (95% CI: 0.90-0.95). Moreover, the prognosis analysis revealed that the plasma GDF-15 levels were significantly higher in patients than controls (standardized mean difference: 2.91, CI 2.79-3.04 and P < 0.00001), and the odds ratio of 3-year overall survival rate was 4.05 (95% CI: 1.92-8.51 and P = 0.0002).

Discussion

GDF-15 exhibits strong potential as both a diagnostic and prognostic biomarker in lung cancer, distinguishing effectively between patients and healthy individuals. These findings support its further exploration and potential integration into clinical practice.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024519807.

Growth and differentiation factor 15: An emerging therapeutic target for brain diseases

Growth and differentiation factor 15 (GDF15), a member of the transforming growth factor-βsuperfamily, is considered a stress response factor and has garnered increasing attention in recent years due to its roles in neurological diseases. Although many studies have suggested that GDF15 expression is elevated in patients with neurodegenerative diseases (NDDs), glioma, and ischemic stroke, the effects of increased GDF15 expression and the potential underlying mechanisms remain unclear. Notably, many experimental studies have shown the multidimensional beneficial effects of GDF15 on NDDs, and GDF15 overexpression is able to rescue NDD-associated pathological changes and phenotypes. In glioma, GDF15 exerts opposite effects, it is both protumorigenic and antitumorigenic. The causes of these conflicting findings are not comprehensively clear, but inhibiting GDF15 is helpful for suppressing tumor progression. GDF15 is also regarded as a biomarker of poor clinical outcomes in ischemic stroke patients, and targeting GDF15 may help prevent this disease. Thus, we systematically reviewed the synthesis, transcriptional regulation, and biological functions of GDF15 and its related signaling pathways within the brain. Furthermore, we explored the potential of GDF15 as a therapeutic target and assessed its clinical applicability in interventions for brain diseases. By integrating the latest research findings, this study provides new insights into the future treatment of neurological diseases.

GDF15, EGF, and Neopterin in Assessing Progression of Pediatric Chronic Kidney Disease Using Artificial Intelligence Tools-A Pilot Study

Cell-mediated immunity and chronic inflammation are hallmarks of chronic kidney disease (CKD). Growth differentiation factor 15 (GDF15) is a marker of inflammation and an integrative signal in stress conditions. Epidermal growth factor (EGF) is a tubule-specific protein that modulates the regeneration of injured renal tubules. Neopterin is a product of activated monocytes and macrophages and serves as a marker of cell-mediated immunity. Our aim was to assess the role of the above-mentioned parameters in the progression of CKD in children using artificial intelligence tools. The study group consisted of 151 children with CKD stages 1-5. EGF, GDF15, and neopterin serum concentrations were assessed by ELISA. The patients' anthropometric data, biochemical parameters, EGF, GDF15, and neopterin serum values were implemented into the artificial neural network (ANN). The most precise model contained EGF, GDF15, and neopterin as input parameters and classified patients into either CKD 1-3 or CKD 4-5 groups with an excellent accuracy of 96.77%. The presented AI model, with serum concentrations of EGF, GDF15, and neopterin as input parameters, may serve as a useful predictor of CKD progression. It suggests the essential role of inflammatory processes in the renal function decline in the course of CKD in children.

Central mechanisms of emesis: A role for GDF15

BACKGROUND

Nausea and emesis are ubiquitously reported medical conditions and often present as treatment side effects along with polymorbidities contributing to detrimental life-threatening outcomes, such as poor nutrition, lower quality of life, and unfavorable patient prognosis. Growth differentiation factor 15 (GDF15) is a stress response cytokine secreted by a wide variety of cell types in response to a broad range of stressors. Circulating GDF15 levels are elevated in a range of medical conditions characterized by cachexia and malaise. In recent years, GDF15 has gained scientific and translational prominence with the discovery that its receptor, GDNF family receptor α-like (GFRAL), is expressed exclusively in the hindbrain. GFRAL activation may results in profound anorexia and body weight loss, effects which have attracted interest for the pharmacological treatment of obesity.

PURPOSE

This review highlights compelling emerging evidence indicating that GDF15 causes anorexia through the induction of nausea, emesis, and food aversions, which encourage a perspective on GDF15 system function in physiology and behavior beyond homeostatic energy regulation contexts. This highlights the potential role of GDF15 in the central mediation of nausea and emesis following a variety of physiological, and pathophysiological conditions such as chemotherapy-induced emesis, hyperemesis gravidarum, and cyclic vomiting syndrome.

A scoping review and hypothetical framework about the interplay between oxytocin and eating disorders

INTRODUCTION

Despite emerging evidence on oxytocin's role in eating disorders,there is a need for a comprehensive review to integrate findings across neurobiological, genetic, hormonal, and therapeutic dimensions. This scoping review synthesizes existing literature on OXT's role in EDs and proposes a new theoretical perspective based on diverse research findings.

METHODS

In accordance with PRISMA guidelines, we systematically synthesized all peer-reviewed articles indexed on PubMed which focused on both OXT and EDs as of December 2023 (k = 32 studies, n = 1942 participants). After summarizing this literature in tables, we completed the narrative synthesis with a discussion of mechanisms informed by an unstructured literature review.

RESULTS

The existing studies propose a connection between OXT receptor Oxtr polymorphisms and ED diagnoses, severity of symptoms, macronutrient preferences, reward function, and early life stress. In addition, OXT plasma levels normalized with ED symptom reduction. Although some OXT studies have failed to show therapeutic changes in food intake and weight, few have reported ameliorations in brain function, food-related attentional bias, cognition, and emotional regulation. Some data have also suggested a contributory role of the transforming growth factor β (TGFβ) and sterol regulatory element binding proteins (SREBPs) to the etiology of EDs through Oxtr expression.

CONCLUSION

Although the current evidence does not support OXT as a standalone cause of or treatment for EDs, OXT research holds promise as a way of identifying future therapies, and OXT itself may serve as a valuable adjunct.

Interdependent roles for growth differentiation factor-15 (GDF15) and LIMS1 in regulating cell migration: Implications for colorectal cancer metastasis

Colorectal cancer (CRC) ranks second in mortality worldwide while metastasis accounts for most CRC-related deaths. Thus, understanding cell migration, a crucial step in metastasis, is imperative for developing new therapies. Growth Differentiation Factor-15 (GDF15), a member of the Transforming Growth Factor β superfamily, is overexpressed in CRC and promotes metastasis with a so far unknown mechanism. LIMS1 is a cell-matrix adhesion prosurvival protein that is also overexpressed in CRC and localized at the tumor invasive front, while bioinformatics analysis shows that both genes exhibit the same expression pattern in metastatic CRC samples. In the present study, treatment of low-aggressiveness HT29 CRC cells with human recombinant GDF15 (hrGDF15) led to increased LIMS1 expression, increased mRNA level of RhoGTPases RAC1 and RHOA but not CDC42, and increased migration. Conversely, GDF15 or LIMS1-siRNA-mediated silencing in invasive HCT116 cells resulted in downregulation of LIMS1 and GDF15 respectively, decreased RAC1, and RHOA as well as reduced cell migration, which were fully restored by hrGDF15 treatment both in GDF15 and LIMS1-siRNA-treated cells. Our findings indicate that GDF15 and LIMS1 have an interdependent role in the migration process which renders them potent targets for the development of novel therapeutic strategies to inhibit metastatic spread.

A Growth Differentiation Factor 15 Receptor Agonist in Randomized Placebo-Controlled Trials in Healthy or Obese Persons

BACKGROUND

Growth differentiation factor 15 (GDF15), a divergent member of the TGF-β superfamily, signals via the hindbrain glial-derived neurotrophic factor receptor alpha-like and rearranged during transfection receptor co-receptor (GFRAL-RET) complex. In nonclinical species, GDF15 is a potent anorexigen leading to substantial weight loss. MBL949 is a half-life extended recombinant human GDF15 dimer.

METHODS

MBL949 was evaluated in multiple nonclinical species, and then in humans, in 2 randomized and placebo-controlled clinical trials. In the phase 1, first-in-human, single ascending dose trial, MBL949 or placebo was injected subcutaneously to overweight and obese healthy volunteers (n = 65) at doses ranging from 0.03 to 20 mg. In phase 2, MBL949 or placebo was administered subcutaneously every other week for a total of 8 doses to obese participants (n = 126) in 5 different dose regimens predicted to be efficacious based on data from the phase 1 trial.

RESULTS

In nonclinical species, MBL949 was generally safe and effective with reduced food intake and body weight in mice, rats, dogs, and monkeys. Weight loss was primarily from reduced fat, and metabolic endpoints improved. A single ascending dose study in overweight or obese healthy adults demonstrated mean terminal half-life of 18 to 22 days and evidence of weight loss at the higher doses. In the phase 2, weight loss was minimal following biweekly dosing of MBL949 for 14 weeks. MBL949 was safe and generally tolerated in humans over the dose range tested, adverse events of the gastrointestinal system were the most frequent observed.

CONCLUSION

The prolonged half-life of MBL949 supports biweekly dosing in patients. MBL949 had an acceptable safety profile. The robust weight loss observed in nonclinical species did not translate to weight loss efficacy in humans.

Mechanisms and pharmacotherapy of cancer cachexia-associated anorexia

Cachexia is a multifactorial metabolic syndrome characterized by weight and skeletal muscle loss caused by underlying illnesses such as cancer, heart failure, and renal failure. Inflammation, insulin resistance, increased muscle protein degradation, decreased food intake, and anorexia are the primary pathophysiological drivers of cachexia. Cachexia causes physical deterioration and functional impairment, loss of quality of life, lower response to active treatment, and ultimately morbidity and mortality, while the difficulties in tackling cachexia in its advanced phases and the heterogeneity of the syndrome among patients require an individualized and multidisciplinary approach from an early stage. Specifically, strategies combining nutritional and exercise interventions as well as pharmacotherapy that directly affect the pathogenesis of cachexia, such as anti-inflammatory, metabolism-improving, and appetite-stimulating agents, have been proposed, but none of which have demonstrated sufficient evidence to date. Nevertheless, several agents have recently emerged, including anamorelin, a ghrelin receptor agonist, growth differentiation factor 15 neutralization therapy, and melanocortin receptor antagonist, as candidates for ameliorating anorexia associated with cancer cachexia. Therefore, in this review, we outline cancer cachexia-associated anorexia and its pharmacotherapy, including corticosteroids, progesterone analogs, cannabinoids, anti-psychotics, and thalidomide which have been previously explored for their efficacy, in addition to the aforementioned novel agents, along with their mechanisms.

GDF15-GFRAL signaling drives weight loss and lipid metabolism in mouse model of amyotrophic lateral sclerosis

Weight loss is a common early sign in amyotrophic lateral sclerosis (ALS) patients and negatively correlates with survival. In different cancers and metabolic disorders, high levels of serum growth differentiation factor 15 (GDF15) contribute to a decrease of food intake and body weight, acting through GDNF family receptor alpha-like (GFRAL). Here we report that GDF15 is highly expressed in the peripheral blood of ALS patients and in the hSOD1G93A mouse model and that GFRAL is upregulated in the brainstem of hSOD1G93A mice. We demonstrate that the localized GFRAL silencing by shRNA in the area postrema/nucleus tractus solitarius of hSOD1G93A mice induces weight gain, reduces adipose tissue wasting, ameliorates the motor function and muscle atrophy and prolongs the survival time. We report that microglial cells could be involved in mediating these effects because their depletion with PLX5622 reduces brainstem GDF15 expression, weight loss and the expression of lipolytic genes in adipose tissue. Altogether these results reveal a key role of GDF15-GFRAL signaling in regulating weight loss and the alteration of and lipid metabolism in the early phases of ALS.

Growth differentiation factor-15 as a biomarker for intensive care unit-acquired weakness: a meta-analysis

Background

Growth differentiation factor-15 (GDF-15) may be a potential biomarker for intensive care unit-acquired weakness (ICU-AW). In this study, we aimed to quantitative analysis the levels of GDF-15 in patients with ICU-AW and in non-ICU-AW, and then to determine its potential diagnostic utility.

Methods

Two researchers separately conducted a systematic search of the relevant studies up to May 2023 in various literature databases (PubMed, Cochrane, Web of Science, Embase, and CINAHL). Studies were selected according to the inclusion and exclusion criteria, and quality evaluation of the included studies was conducted by using QUADAS-2 provided by Review Manager 5.3. The software packages Meta Disc (C1.4) and Stata17.0 were used for the meta-analysis. The data were combined with fixed-effects model, and the summary receiver operating characteristic curve was drawn to evaluate the overall diagnostic accuracy of GDF-15.

Results

We identified 6 eligible studies comprising 401 patients with ICU-AW. The sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) for the discriminative performance of GDF-15 as a diagnostic biomarker were 0.82 (95% confidence interval (CI):0.78-0.86), 0.83 (95% CI: 0.61-0.88), 21.39 (95% CI: 13.36-34.24), and 0.88 (95% CI: 0.85-0.91), respectively.

Conclusion

GDF-15 is a candidate biomarker in diagnosing of ICU-AW from non-ICU-AW.

New Biomarkers in the Prognostic Assessment of Acute Heart Failure with Reduced Ejection Fraction: Beyond Natriuretic Peptides

Natriuretic peptides are established biomarkers related to the prognosis of heart failure. New biomarkers have emerged in the field of cardiovascular disease. The prognostic value of these biomarkers in heart failure with reduced left ventricular ejection fraction is not well-established. We conducted a prospective, single-centre study, including (July 2019 to March 2023) 104 patients being consecutively admitted with a diagnosis of acute heart failure with reduced ejection fraction decompensation. The median follow-up was 23.5 months, during which 20 deaths (19.4%) and 21 readmissions for heart failure (20.2%) were recorded. Plasma biomarkers, such as NT-proBNP, GDF-15, sST2, suPAR, and FGF-23, were associated with an increased risk of all-cause mortality. However, a Cox regression analysis showed that the strongest predictors of mortality were an estimated glomerular filtration rate (HR 0.96 [0.93-0.98]), GDF-15 (HR 1.3 [1.16-1.45]), and sST2 (HR 1.2 [1.11-1.35]). The strongest predictive model was formed by the combination of the glomerular filtration rate and sST2 (C-index 0.758). In conclusion, in patients with acute decompensated heart failure with reduced ejection fraction, GDF-15 and sST2 showed the highest predictive power for all-cause mortality, which was superior to other established biomarkers such as natriuretic peptides. GDF-15 and sST2 may provide additional prognostic information to improve the prognostic assessment.

The Role of Mitokines in Diabetic Nephropathy

Diabetic nephropathy (DN) has gradually become one of the main causes of end-stage renal disease (ESRD). However, there is still a lack of effective preventive measures to delay its progression. As the energy factory in the cell, mitochondria play an irreplaceable role in maintaining cell homeostasis. Interestingly, recent studies have shown that in addition to maintaining homeostasis in cells in which mitochondria reside, when mitochondrial perturbations occur in one tissue, distal tissues can also sense and act through mitochondrial stress response pathways through a group of proteins or peptides called "mitokines". Here, we reviewed the mitokines that have been found thus far and summarized their research progress in DN. Finally, we explored the possibility of mitokines as potential therapeutic targets for DN.

Neutralizing GDF-15 can overcome anti-PD-1 and anti-PD-L1 resistance in solid tumours

Cancer immunotherapies with antibodies blocking immune checkpoint molecules are clinically active across multiple cancer entities and have markedly improved cancer treatment1. Yet, response rates are still limited, and tumour progression commonly occurs2. Soluble and cell-bound factors in the tumour microenvironment negatively affect cancer immunity. Recently, growth differentiation factor 15 (GDF-15), a cytokine that is abundantly produced by many cancer types, was shown to interfere with antitumour immune response. In preclinical cancer models, GDF-15 blockade synergistically enhanced the efficacy of anti-PD-1-mediated checkpoint inhibition3. In a first-in-human phase 1-2a study (GDFATHER-1/2a trial, NCT04725474 ), patients with advanced cancers refractory to anti-PD-1 or anti-PD-L1 therapy (termed generally as anti-PD-1/PD-L1 refractoriness) were treated with the neutralizing anti-GDF-15 antibody visugromab (CTL-002) in combination with the anti-PD-1 antibody nivolumab. Here we show that durable and deep responses were achieved in some patients with non-squamous non-small cell lung cancer and urothelial cancer, two cancer entities identified as frequently immunosuppressed by GDF-15 in an in silico screening of approximately 10,000 tumour samples in The Cancer Genome Atlas database. Increased levels of tumour infiltration, proliferation, interferon-γ-related signalling and granzyme B expression by cytotoxic T cells were observed in response to treatment. Neutralizing GDF-15 holds promise in overcoming resistance to immune checkpoint inhibition in cancer.

Identification of Ferroptosis-Associated Genes in Primary Open-Angle Glaucoma through Bioinformatics Analysis

This study aims to examine ferroptosis-associated genes in primary open-angle glaucoma (POAG) and offer new insights into the underlying disease mechanisms and potential therapeutic approaches. Differentially expressed genes (DEGs) between the POAG and control groups were identified using bioinformatics analysis and subsequently intersected with a ferroptosis gene set to isolate ferroptosis-related DEGs (Ferr DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to examine their biological functions. Core genes were identified through protein-protein interaction (PPI) network and Friends analysis. The diagnostic potential of core Ferr DEGs was assessed using receiver operating characteristic (ROC) curve analysis, while immune cell infiltration was examined using the CIBERSORT algorithm. Additionally, Spearman correlation analysis was used to examine the relationships between the identified genes and immune cell populations. A total of 25 Ferr DEGs were identified, with DDIT4, GDF15, NAMPT, HBA1, and IGFBP7 recognized as key core genes. ROC analysis demonstrated that these genes exhibited high diagnostic accuracy, with an AUC > 0.7. Additionally, the infiltration levels of memory B cells and macrophage_M2 were significantly elevated in POAG tissues compared to the control group. Notably, the core genes revealed significant correlations with various immune cell types. Our findings underscore the involvement of ferroptosis-related genes in POAG pathogenesis and highlight their potential as diagnostic biomarkers and therapeutic targets. Future research should focus on validating these findings in clinical settings and exploring the therapeutic modulation of ferroptosis in POAG management.

Growth Differentiation Factor 15 during pregnancy and postpartum as captured in blood, cerebrospinal fluid and placenta: A cohort study on associations with maternal mental health

INTRODUCTION

Growth Differentiation Factor 15 (GDF15) increases substantially during pregnancy and is primarily produced by the placenta. Elevated levels of GDF15 have been associated with mental health problems in non-perinatal populations, higher corticosterone levels, and decreased estrogen receptor activity. However, the role of GDF15 in mental health during the perinatal transition remains unknown. This longitudinal study is the first to evaluate pregnancy levels of GDF15 in cerebrospinal fluid (cGDF15), plasma (pGDF15) and placenta GDF15 mRNA, along with mapping plasma GDF15 (pGDF15) level changes from late pregnancy to early postpartum. Moreover, we aimed to evaluate the association between pregnancy cGDF15 levels and cortisol early postpartum, evaluate the association between pregnancy cGDF15 levels and mental health in pregnancy and postpartum, and evaluate the association between pGDF15 and estrogens and high-sensitivity C-reactive protein (CRP).

METHODS

We included data from 95 women scheduled for a planned cesarean section and obtained cerebrospinal fluid (CSF) and plasma levels of GDF15. We quantified GDF15 mRNA levels in placenta biopsies. Estrogens, high-sensitivity CRP, and mental health measures were further collected on the day or one day before the cesarean section. At five weeks postpartum, mental health measures and saliva samples for cortisol analyses were collected. Correlation analyses for GDF15 in CSF, plasma, and placenta mRNA were performed, along with association analyses for pregnancy cGDF15, Cortisol Awakening Response, and mental health outcomes.

RESULTS

We demonstrated a strong correlation between cGDF15 and pGDF15 (r=0.52; p<0.001) and found that both cGDF15 and pGDF15 correlated with placenta GDF15 mRNA*placental weight (r=0.62, p<0.001 and r=0.44, p=0.008, respectively). During late pregnancy, both estradiol (E2) and estriol (E3) were significantly associated with pGDF15 levels (E2: p=0.002; E3: p(corrected)<0.001). Finally, we found that cGDF15 levels were not associated with self-reported mental well-being or the Cortisol Awakening Response or absolute cortisol at awakening postpartum.

CONCLUSION

This novel study points to the unique hormonal landscape during the perinatal transition and the specific role of GDF15 in pregnancy, which appears uncoupled with perinatal mental health and cortisol outcomes. Our data also strongly imply that the overall amount of circulating GDF15 in late pregnancy is closely related to placenta size.

Role of GDF-15 in diabetic nephropathy: mechanisms, diagnosis, and therapeutic potential

PURPOSE

Growth differentiation factor 15 (GDF-15) is a cytokine involved in regulating homeostasis, and its expression is up-regulated in response to injury, stress, and inflammation. This study explored the role of GDF-15 in diabetic nephropathy (DN), a severe complication of diabetes mellitus, and its potential as a biomarker for disease progression.

METHODS

As a member of the transforming growth factor-β superfamily, GDF-15 exhibits its renal protective functions primarily through its anti-inflammatory effects and the up-regulation of other renal protective factors. This study evaluated the association between circulating GDF-15 levels and DN progression, examining the underlying mechanisms.

RESULTS

Circulating GDF-15 levels are closely linked to the development and progression of DN. While existing research has yielded some consistent conclusions, a comprehensive understanding of the role of GDF-15 in DN pathogenesis is needed to identify new therapeutic targets and strategies.

CONCLUSION

GDF-15 has the potential to be a prognostic and diagnostic biomarker for DN. It is crucial to establish appropriate reference ranges and explore their clinical utility in routine practice for validating the role of GDF-15 in DN management. Further interventional studies are required to confirm its clinical value in diagnosing and predicting the progression of DN.

Determinants of growth differentiation factor 15 plasma levels in outpatients with peripheral arterial disease

Background

Growth differentiation factor 15 (GDF-15) is a robust prognostic biomarker in patients with cardiovascular (CV) disease, and a better understanding of its clinical determinants is desirable. We aimed to study the associations between GDF-15 levels and traditional CV risk factors, indicators of atherosclerotic burden, and cardiac geometry and dysfunction in outpatients with peripheral arterial disease (PAD).

Methods

An explorative cross-sectional study (Study of Atherosclerosis in Vastmanland, Västerås, Sweden) included 439 outpatients with carotid or lower extremity PAD. The mean age was 70 years (standard deviation [SD] 7), and 59% of the patients were men. Plasma levels of GDF-15 were obtained along with potential determinants, including medical history, biochemical data, echocardiographic measures of cardiac geometry and function, ankle-brachial index (ABI), and carotid ultrasonographic data on intima-media thickness (IMT) and occurrence of carotid stenosis. The relations between GDF-15 concentrations (transformed with the natural logarithm) and the different determinants were evaluated using uni- and multivariable linear regression models. All pre-specified variables were included in the multivariable models.

Results

The multivariable analysis identified independent relations of GDF-15 with several of the included variables (adjusted R 2 = 0.48). Diabetes (beta coefficient [β] of 0.37, 95% confidence interval [95% CI] 0.25 to 0.50), low-density lipoprotein (LDL) cholesterol (β = -0.22, 95% confidence interval [CI]: -0.34 to -0.09), and physical activity (β = -0.16, 95% CI: -0.25 to -0.06) had the strongest associations. In contrast, no significant independent associations with GDF-15 level were observed for cardiac geometry and function, ABI, IMT, or carotid stenosis.

Conclusions

Circulating GDF-15 is more strongly associated with traditional CV risk factors, especially diabetes, LDL cholesterol, and physical activity than with specific indicators of atherosclerotic burden or cardiac dysfunction. To better understand the pathophysiological role of GDF-15 and its link to clinical outcomes in patients with PAD, future studies should focus on the metabolic processes involved in atherosclerotic disease.

A systematic review of the neuroprotective role and biomarker potential of GDF15 in neurodegeneration

Neurodegeneration is characteristically multifaceted, with limited therapeutic options. One of the chief pathophysiological mechanisms driving these conditions is neuroinflammation, prompting increasing clinical interest in immunomodulatory agents. Growth differentiation factor 15 (GDF15; previously also called macrophage inhibitory cytokine-1 or MIC-1), an anti-inflammatory cytokine with established neurotrophic properties, has emerged as a promising therapeutic agent in recent decades. However, methodological challenges and the delayed identification of its specific receptor GFRAL have hindered research progress. This review systematically examines literature about GDF15 in neurodegenerative diseases and neurotrauma. The evidence collated in this review indicates that GDF15 expression is upregulated in response to neurodegenerative pathophysiology and increasing its levels in preclinical models typically improves outcomes. Key knowledge gaps are addressed for future investigations to foster a more comprehensive understanding of the neuroprotective effects elicited by GDF15.

GDF15/MIC-1: a stress-induced immunosuppressive factor which promotes the aging process

The GDF15 protein, a member of the TGF-β superfamily, is a stress-induced multifunctional protein with many of its functions associated with the regulation of the immune system. GDF15 signaling provides a defence against the excessive inflammation induced by diverse stresses and tissue injuries. Given that the aging process is associated with a low-grade inflammatory state, called inflammaging, it is not surprising that the expression of GDF15 gradually increases with aging. In fact, the GDF15 protein is a core factor secreted by senescent cells, a state called senescence-associated secretory phenotype (SASP). Many age-related stresses, e.g., mitochondrial and endoplasmic reticulum stresses as well as inflammatory, metabolic, and oxidative stresses, induce the expression of GDF15. Although GDF15 signaling is an effective anti-inflammatory modulator, there is robust evidence that it is a pro-aging factor promoting the aging process. GDF15 signaling is not only an anti-inflammatory modulator but it is also a potent immunosuppressive enhancer in chronic inflammatory states. The GDF15 protein can stimulate immune responses either non-specifically via receptors of the TGF-β superfamily or specifically through the GFRAL/HPA/glucocorticoid pathway. GDF15 signaling stimulates the immunosuppressive network activating the functions of MDSCs, Tregs, and M2 macrophages and triggering inhibitory immune checkpoint signaling in senescent cells. Immunosuppressive responses not only suppress chronic inflammatory processes but they evoke many detrimental effects in aged tissues, such as cellular senescence, fibrosis, and tissue atrophy/sarcopenia. It seems that the survival functions of GDF15 go awry in persistent inflammation thus promoting the aging process and age-related diseases.

Diagnostic value of serum GDF-15 in patients with pseudomyxoma peritonei

BACKGROUND AND AIMS

Pseudomyxoma peritonei (PMP) is a rare malignancy that lacks a highly sensitive and specific biomarker for its diagnosis. Identifying reliable serum markers is crucial for improving the diagnostic accuracy and management of PMP. This study aims to explore the diagnostic value of serum growth differentiation factor 15 (GDF-15) in patients with PMP.

MATERIAL AND METHODS

We carried on a 1:1 matched case-control study. 44 patients with PMP hospitalized in Aerospace Center Hospital were recruited as cases, and 44 sex- and age-matched apparently healthy participants were selected as controls. The serum GDF-15 concentrations were tested using an ELISA method. The diagnostic value of GDF-15 in PMP patients was assessed by receiver operating characteristic (ROC) curve analysis.

RESULTS

The median serum GDF-15 level in PMP patients was 1192.77 (843.03-1879.06) pg/mL, notably higher than that in healthy controls [533.27 (410.46-641.47) pg/mL] (P<0.001). The area under the curve (AUC) of serum GDF-15 for PMP diagnosis was 0.907, the optimal diagnostic threshold value was 644.58 pg/mL, the sensitivity was 93.18 %, and the specificity was 77.27 %. The AUC of GDF-15 combined with carbohydrate antigen 125 (CA125) was larger than that of GDF-15 alone (P=0.027), and the sensitivity and specificity achieved 86.36 % and 95.45 %. GDF-15 levels showed a significant correlation with age (P=0.042), with younger PMP patients exhibiting notably lower concentrations of GDF-15 compared to older patients.

CONCLUSION

Serum GDF-15 could become a new marker for the PMP diagnosis. The combination of GDF-15 and CA125 demonstrated superior diagnostic performance for PMP compared to GDF-15 alone, achieving a sensitivity of 86.36% and a specificity of 95.45%.

Targeting the GDF15 Signalling for Obesity Treatment: Recent Advances and Emerging Challenges

The growth differentiation factor 15 (GDF15)-glial cell-derived neurotrophic factor family receptor alpha-like (GFRAL) pathway plays a crucial role in the regulation of metabolism, appetite and body weight control. Obesity is an increasingly prevalent chronic disease worldwide, necessitating effective treatment strategies. Recent preclinical and clinical studies have highlighted that targeting the GDF15-GFRAL signalling pathway is a promising approach for treating obesity, particularly because it has minimal impact on skeletal muscle mass, which is essential to preserve during weight loss. Given its distinctive mechanisms, the GDF15-GFRAL axis represents an attractive target for addressing various metabolic disorders, especially obesity. In this review, we will explore how the GDF15-GFRAL axis is regulated, its distribution in the body and its role in the regulation of metabolism, appetite and obesity. Additionally, we will discuss recent advances and potential challenges in targeting the GDF15-GFRAL axis for obesity treatment.

GDF15 and LCN2 for early detection and prognosis of pancreatic cancer

BACKGROUND

The prognosis of pancreatic ductal adenocarcinomas (PDAC) remains very poor, emphasizing the critical importance of early detection, where biomarkers offer unique potential. Although growth differentiation factor 15 (GDF15) and Lipocalin 2 (LCN2) have been linked to PDAC, their precise roles as biomarkers are uncertain.

METHODS

Circulating levels of GDF15 and LCN2 were examined in human PDAC patients, heathy controls, and individuals with benign pancreatic diseases. Circulating levels of IL-6, CA19-9, and neutrophil-to-lymphocyte ratio (NLR) were measured for comparisons. Correlations between PDAC progression and overall survival were assessed. A mouse PDAC model was employed for comprehensive analyses, complementing the human studies by exploring associations with various metabolic and inflammatory parameters. Sensitivity and specificity of the biomarkers were evaluated.

FINDINGS

Our results demonstrated elevated levels of circulating GDF15 and LCN2 in PDAC patients compared to both healthy controls and individuals with benign pancreatic diseases, with higher GDF15 levels associated with disease progression and increased mortality. In PDAC mice, circulating GDF15 and LCN2 progressively increased, correlating with tumor growth, behavioral manifestations, tissue and molecular pathology, and cachexia development. GDF15 exhibited highly sensitive and specific for PDAC patients compared to CA19-9, IL-6, or NLR, while LCN2 showed even greater sensitivity and specificity in PDAC mice. Combining GDF15 and LCN2, or GDF15 and CA19-9, enhanced sensitivity and specificity.

INTERPRETATION

Our findings indicate that GDF15 holds promise as a biomarker for early detection and prognosis of PDAC, while LCN2 could strengthen diagnostic panels.

Proteome-Wide Mendelian Randomisation Identifies Causal Links of Plasma Proteins With Periodontitis

OBJECTIVE

Periodontitis is a complex and multifactorial disease and it is challenging to decipher its underlying causes and mechanisms. This study attempted to explore potential circulating proteins in connection to periodontitis through proteome-wide Mendelian randomisation (MR).

METHODS

We analysed 1722 circulating proteins to identify prospective drug targets for tackling periodontitis, using the genomic dataset from the FinnGen study. Two-sample MR was conducted to evaluate the bidirectional relationship between circulating proteins and periodontitis risk. A dataset from the UK Biobank was used to validate the findings. Single-cell analysis was performed to assess the cellular expression of the identified proteins within gingival tissues.

RESULTS

MR analyses found that genetically predicted circulating levels of von Willebrand factor A domain-containing 1 (von Willebrand factor A domain containing 1 [VWA1], odds ratios: 0.94, 95% CI 0.92-0.97, P = 1.28 × 10-5) were inversely associated with periodontitis. In contrast, the level of growth differentiation factor 15 (growth differentiation factor 15 [GDF15], odds ratios: 1.05, 95% CI 1.02-1.07, P = 2.12 × 10-5) might be associated with an increased risk of periodontitis. Single-cell analysis indicated that VWA1 was primarily expressed in endothelial cells of healthy gingival tissues, while the main source of GDF15 was not derived from periodontal cells.

CONCLUSIONS

The present study suggests that certain plasma proteins like VWA1 and GDF15 may be potentially indicative of the risk and susceptibility to periodontitis. These proteins could possibly be the potential therapeutic targets for treating periodontitis, and further investigation is highly warranted.

GDF15 propeptide promotes bone metastasis of castration-resistant prostate cancer by augmenting the bone microenvironment

BACKGROUND

Bone metastasis (BM) is a common and fatal condition in patients with castration-resistant prostate cancer (CRPC). However, there are no useful blood biomarkers for CRPC with BM, and the mechanism underlying BM is unclear. In this study, we investigated precise blood biomarkers for evaluating BM that can improve the prognosis of patients with CRPC.

METHODS

We comprehensively examined culture supernatants from four prostate cancer (PCa) cell lines using Orbitrap mass spectrometry to identify specific proteins secreted abundantly by PCa cells. The effects of this protein to PCa cells, osteoblasts, osteoclasts were examined, and BM mouse model. In addition, we measured the plasma concentration of this protein in CRPC patients for whom bone scan index (BSI) by bone scintigraphy was performed.

RESULTS

A total of 2,787 proteins were identified by secretome analysis. We focused on GDF15 propeptide (GDPP), which is secreted by osteoblasts, osteoclasts, and PCa cells. GDPP promoted the proliferation, invasion, and migration of PC3 and DU145 CRPC cells, and GDPP aggravated BM in a mouse model. Importantly, GDPP accelerated bone formation and absorption in the bone microenvironment by enhancing the proliferation of osteoblasts and osteoclasts by upregulating individual transcription factors such as RUNX2, OSX, ATF4, NFATc1, and DC-STAMP. In clinical settings, including a total of 416 patients, GDPP was more diagnostic of BM than prostate-specific antigen (PSA) (AUC = 0.92 and 0.78) and the seven other blood biomarkers (alkaline phosphatase, lactate dehydrogenase, bone alkaline phosphatase, tartrate-resistant acid phosphatase 5b, osteocalcin, procollagen I N-terminal propeptide and mature GDF15) in patients with CRPC. The changes in BSI over time with systemic treatment were correlated with that of GDPP (r = 0.63) but not with that of PSA (r = -0.16).

CONCLUSIONS

GDPP augments the tumor microenvironment of BM and is a novel blood biomarker of BM in CRPC, which could lead to early treatment interventions in patients with CRPC.

Diversity of Microglia-Derived Molecules with Neurotrophic Properties That Support Neurons in the Central Nervous System and Other Tissues

Microglia, the brain immune cells, support neurons by producing several established neurotrophic molecules including glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Modern analytical techniques have identified numerous phenotypic states of microglia, each associated with the secretion of a diverse set of substances, which likely include not only canonical neurotrophic factors but also other less-studied molecules that can interact with neurons and provide trophic support. In this review, we consider the following eight such candidate cytokines: oncostatin M (OSM), leukemia inhibitory factor (LIF), activin A, colony-stimulating factor (CSF)-1, interleukin (IL)-34, growth/differentiation factor (GDF)-15, fibroblast growth factor (FGF)-2, and insulin-like growth factor (IGF)-2. The available literature provides sufficient evidence demonstrating murine cells produce these cytokines and that they exhibit neurotrophic activity in at least one neuronal model. Several distinct types of neurotrophic activity are identified that only partially overlap among the cytokines considered, reflecting either their distinct intrinsic properties or lack of comprehensive studies covering the full spectrum of neurotrophic effects. The scarcity of human-specific studies is another significant knowledge gap revealed by this review. Further studies on these potential microglia-derived neurotrophic factors are warranted since they may be used as targeted treatments for diverse neurological disorders.

Growth differentiation factor 15 (GDF15) predicts relapse free and overall survival in unresected locally advanced non-small cell lung cancer treated with chemoradiotherapy

INTRODUCTION

Growth differentiation factor 15 (GDF15) is a cytokine of the TGFβ family. Here, we analyzed GDF15 levels in patients with locally advanced non-small cell lung cancer (LA-NSCLC) who participated in OCOG-ALMERA (NCT02115464), a phase II randomized clinical trial, that investigated metformin in combination with standard of care concurrent chemoradiotherapy (cCRT). OCOG-ALMERA was not able to demonstrate benefit in the metformin arm. Therefore, biomarker studies are needed to better define stratification parameters for future trials.

METHODS

Patients were randomized to treatment with platinum-based chemotherapy and concurrent chest radiotherapy (60-66 Gy), with or without metformin (2000 mg/d). The trial collected tumor volume parameters, survival outcomes, and patient blood plasma at baseline, during (weeks 1 and 6) and 6 months after cCRT. Plasma GDF15 levels were assayed with the ELISA method. Statistical analyses explored associations between GDF15, survival outcomes, and radiotherapy tumor volumes.

RESULTS

Baseline plasma levels of GDF15 were elevated in study patients, they increased during cCRT (p < 0.001), and the addition of metformin was associated with a further increase (week 6, p = 0.033). Baseline GDF15 levels correlated with the radiotherapy gross target volume (GTV, p < 0.01), while week 1 of radiotherapy levels correlated with radiotherapy planned target volume (PTV, p < 0.006). In multivariate analysis, baseline plasma GDF15 was prognostic for poor relapse-free (RFS) and overall survival (OS) (p = 0.005 and p = 0.002, respectively).

CONCLUSIONS

GDF15 is a plasma marker that responds to the treatment of unresected LA-NSCLC with cCRT and metformin. GDF15 levels correspond with tumor volume and increased GDF15 levels predict for poor RFS and OS. These results require validation in larger clinical trial datasets.

The GDF15 3' UTR Polymorphism rs1054564 Is Associated with Diabetes and Subclinical Atherosclerosis

Growth differentiation factor 15 (GDF15) is a stress-response cytokine related to a wide variety of metabolic diseases. However, the impact of GDF15-specific genetic variants on the abovementioned conditions is poorly known. The aim of this study was to assess the impact of selected GDF15 single-nucleotide polymorphisms (SNPs) on metabolic disturbances and subclinical atherosclerosis. A cross-sectional study involving 153 participants of a metabolic patient-based cohort was performed. Three selected SNPs (rs888663, rs1054564 and rs1059369) in a locus on chromosome 19 including the GDF15 gene were genotyped by Polymerase Chain Reaction (PCR), and its relationship with the serum GDF15 levels, health status and clinical variables were analyzed. Of the three SNPs analyzed, only rs1054564 showed different distributions between the healthy volunteers and patients suffering lipid alterations and associated disorders. Accordingly, just the rs1054564 variant carriers showed a significant increase in GDF15 serum levels compared to the wild-type carriers. The group of variant carriers showed a higher frequency of individuals with diabetes, compared to the wild-type carrier group, without showing differences in other metabolic conditions. Additionally, the frequency of individuals with atherosclerotic carotid plaque was higher in the rs1054564 variant carriers than in the wild-type carriers. Logistic regression models identified that the presence of the rs1054564 variant carriers increase the likelihood for both diabetes and carotid plaque independently of confounding factors. Overall, the findings of this study identify the rs1054564 variant as a potential indicator for the likelihood of diabetes and subclinical atherosclerosis.

GDF15 is required for maintaining subcutaneous adipose tissue lipid metabolic signature

Recent research has identified growth differentiation factor 15 (GDF15) as a crucial factor in various physiological and pathological processes, particularly in energy balance regulation. While the role of GDF15 in modulating energy metabolism through hindbrain GDNF family receptor alpha-like (GFRAL) signaling has been extensively studied, emerging evidence suggests direct peripheral metabolic actions of GDF15. Using knockout mouse models, we investigated GDF15 and GFRAL's roles in adipose tissue metabolism. Our findings indicate that C57BL/6/129/SvJ Gdf15-KO mice exhibit impaired expression of de novo lipogenesis enzymes in subcutaneous adipose tissue (sWAT). In contrast, C57BL/6J Gfral-KO mice showed no impairments compared to wild-type (WT) littermates. RNA-Seq analysis of sWAT in Gdf15-KO mice revealed a broad downregulation of genes involved in lipid metabolism. Importantly, our study uncovered sex-specific effects, with females being more affected by GDF15 loss than males. Additionally, we observed a fasting-induced upregulation of GDF15 gene expression in sWAT of both mice and humans, reinforcing this factor's role in adipose tissue lipid metabolism. In conclusion, our research highlights an essential role for GDF15 in sWAT lipid metabolic homeostasis. These insights enhance our understanding of GDF15's functions in adipose tissue physiology and underscore its potential as a therapeutic target for metabolic disorders.

GDF15 Knockout Does Not Substantially Impact Perinatal Body Weight or Neonatal Outcomes in Mice

Growth differentiation factor-15 (GDF15) increases in circulation during pregnancy and has been implicated in food intake, weight loss, complications of pregnancy, and metabolic illness. We used a Gdf15 knockout mouse model (Gdf15-/-) to assess the role of GDF15 in body weight regulation and food intake during pregnancy. We found that Gdf15-/- dams consumed a similar amount of food and gained comparable weight during the course of pregnancy compared with Gdf15+/+ dams. Insulin sensitivity on gestational day 16.5 was also similar between genotypes. In the postnatal period, litter size and survival rates were similar between genotypes. There was a modest reduction in birth weight of Gdf15-/- pups, but this difference was no longer evident from postnatal day 3.5 to 14.5. We observed no detectable differences in milk volume production or milk fat percentage. These data suggest that GDF15 is dispensable for changes in food intake, and body weight as well as insulin sensitivity during pregnancy in a mouse model.

The area postrema: a critical mediator of brain-body interactions

The dorsal vagal complex contains three structures: the area postrema, the nucleus tractus solitarii, and the dorsal motor nucleus of the vagus. These structures are tightly linked, both anatomically and functionally, and have important yet distinct roles in not only conveying peripheral bodily signals to the rest of the brain but in the generation of behavioral and physiological responses. Reports on the new discoveries in these structures were highlights of the symposium. In this outlook, we focus on the roles of the area postrema in mediating brain-body interactions and its potential utility as a therapeutic target, especially in cancer cachexia.

Growth differentiation factor 15: Emerging role in liver diseases

Growth differentiation factor 15 (GDF15) is a cell stress-response cytokine within the transforming growth factor-β (TGFβ) superfamily. It is known to exert diverse effects on many metabolic pathways through its receptor GFRAL, which is expressed in the hindbrain, and transduces signals through the downstream receptor tyrosine kinase Ret. Since the liver is the core organ of metabolism, summarizing the functions of GDF15 is highly important. In this review, we assessed the relevant literature regarding the main metabolic, inflammatory, fibrogenic, tumorigenic and other effects of GDF15 on different liver diseases, including Metabolic dysfunction-associated steatotic liver disease(MASLD), alcohol and drug-induced liver injury, as well as autoimmune and viral hepatitis, with a particular focus on the pathogenesis of MASLD progression from hepatic steatosis to MASH, liver fibrosis and even hepatocellular carcinoma (HCC). Finally, we discuss the prospects of the clinical application potential of GDF15 along with its research and development progress. With better knowledge of GDF15, increasing in-depth research will lead to a new era in the field of liver diseases.

Bitter-tasting drugs tune GDF15 and GLP-1 expression via bitter taste or motilin receptors in the intestine of patients with obesity

OBJECTIVE

Growth differentiation factor 15 (GDF15), a stress related cytokine, was recently identified as a novel satiety signal acting via the GFRAL receptor located in the hindbrain. Bitter compounds are known to induce satiety via the release of glucagon-like peptide 1 (GLP-1) through activation of bitter taste receptors (TAS2Rs, 25 subtypes) on enteroendocrine cells in the gut. This study aimed to investigate whether and how bitter compounds induce a stress response in intestinal epithelial cells to affect GDF15 expression in patients with obesity, thereby facilitating satiety signaling from the gut.

METHODS

The acute effect of oral intake of the bitter-containing medication Plaquenil (hydroxychloroquine sulfate) on plasma GDF15 levels was evaluated in a placebo-controlled, double-blind, randomized, two-visit crossover study in healthy volunteers. Primary crypts isolated from the jejunal mucosa from patients with obesity were stimulated with vehicle or bitter compounds, and the effect on GDF15 expression was evaluated using RT-qPCR or ELISA. Immunofluorescence colocalization studies were performed between GDF15, epithelial cell type markers and TAS2Rs. The role of TAS2Rs was tested by 1) pretreatment with a TAS2R antagonist, GIV3727; 2) determining TAS2R4/43 polymorphisms that affect taste sensitivity to TAS2R4/43 agonists.

RESULTS

Acute intake of hydroxychloroquine sulfate increased GDF15 plasma levels, which correlated with reduced hunger scores and plasma ghrelin levels in healthy volunteers. This effect was mimicked in primary jejunal cultures from patients with obesity. GDF15 was expressed in enteroendocrine and goblet cells with higher expression levels in patients with obesity. Various bitter-tasting compounds (medicinal, plant extracts, bacterial) either increased or decreased GDF15 expression, with some also affecting GLP-1. The effect was mediated by specific intestinal TAS2R subtypes and the unfolded protein response pathway. The bitter-induced effect on GDF15/GLP-1 expression was influenced by the existence of TAS2R4 amino acid polymorphisms and TAS2R43 deletion polymorphisms that may predict patient's therapeutic responsiveness. However, the effect of the bitter-tasting antibiotic azithromycin on GDF15 release was mediated via the motilin receptor, possibly explaining some of its aversive side effects.

CONCLUSIONS

Bitter chemosensory and pharmacological receptors regulate the release of GDF15 from human gut epithelial cells and represent potential targets for modulating metabolic disorders or cachexia.

Growth differentiation factor-15 predicts all-cause death and major adverse cardiovascular events in patients with coronary heart disease: a prospective cohort study

The prognostic value of growth differentiation factor-15 (GDF-15) in predicting long-term adverse outcomes in coronary heart disease (CHD) patients remains limited. Our study examines the association between GDF-15 and adverse outcomes over an extended period in CHD patients and firstly assesses the incremental prognostic effect of incorporating GDF-15 into the Framingham risk score (FRS)-based model. This single-center prospective cohort study included 3,321 patients with CHD categorized into 2,479 acute coronary syndrome (ACS) (74.6%) and 842 non-ACS (25.4%) groups. The median age was 61.0 years (range: 53.0-70.0), and 917 (27.6%) were females. Mortality and major adverse cardiovascular events (MACEs) included cardiovascular mortality, myocardial infarction (MI), stroke, and heart failure (HF) (inclusive of HF episodes requiring outpatient treatment and/or hospital admission). Cox regression models assessed the associations between GDF-15 and the incidence of all-cause mortality and MACEs. Patients were stratified into three groups based on GDF-15 levels: the first tertile group (< 1,370 ng/L), the second tertile group (1,370-2,556 ng/L), and the third tertile group (> 2,556 ng/L). The C-index, integrated discrimination improvement (IDI), net reclassification improvement (NRI), and decision curve analysis (DCA) were used to assess incremental value. Over a median 9.4-year follow-up, 759 patients (22.9%) died, and 1,291 (38.9%) experienced MACEs. The multivariate Cox model indicated that GDF-15 was significantly associated with all-cause mortality (per ln unit increase, HR = 1.49, 95% CI: 1.36-1.64) and MACEs (per ln unit increase, HR = 1.29, 95% CI: 1.20-1.38). These associations persisted when GDF-15 was analyzed as an ordinal variable (p for trend < 0.05). Subgroup analysis of ACS and non-ACS for the components of MACEs separately showed a significant association between GDF-15 and both cardiovascular mortality and HF, but no association was observed between GDF-15 and MI /stroke in both ACS and non-ACS patients. The addition of GDF-15 to the FRS-based model enhanced the discrimination for both all-cause mortality (∆ C-index = 0.009, 95% CI: 0.005-0.014; IDI = 0.030, 95% CI: 0.015-0.047; continuous NRI = 0.631, 95% CI: 0.569-0.652) and MACEs (∆ C-index = 0.009, 95% CI: 0.006-0.012; IDI = 0.026, 95% CI: 0.009-0.042; continuous NRI = 0.593, 95% CI: 0.478-0.682). DCA suggested that incorporating GDF-15 into the FRS-based model demonstrated higher net benefits compared to FRS-based models alone (All-cause mortality: FRS-based model: area under the curve of DCA (AUDC) = 0.0903, FRS-based model + GDF-15: AUDC = 0.0908; MACEs: FRS-based model: AUDC = 0.1806, FRS-based model + GDF-15: AUDC = 0.1833). GDF-15 significantly associates with the long-term prognosis of all-cause mortality and MACEs in CHD patients and significantly improves the prognostic accuracy of the FRS-based model for both outcomes.