Associations Between Plasma Growth and Differentiation Factor-15 with Aging Phenotypes in Muscle, Adipose Tissue, and Bone

Utility of growth differentiation factor-15 as a predictor of cardiovascular surgery outcomes: Current research and future directions

In a world increasingly confronted by cardiovascular diseases (CVDs) and an aging population, accurate risk assessment prior to cardiac surgery is critical. Although effective, traditional risk calculators such as the Japan SCORE, Society of Thoracic Surgeons score, and EuroSCORE II may not completely capture contemporary risks, particularly due to emerging factors such as frailty and sarcopenia. These calculators often focus on regional and ethnic specificity and rely heavily on evaluations based on age and underlying diseases. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine that has been identified as a potential biomarker for sarcopenia and a tool for future cardiac risk assessment. Preoperative plasma GDF-15 levels have been associated with preoperative, intraoperative, and postoperative factors and short- and long-term mortality rates in patients undergoing cardiac surgery. Increased plasma GDF-15 levels have prognostic significance, having been correlated with the use of cardiopulmonary bypass during surgery, amount of bleeding, postoperative acute kidney injury, and intensive care unit stay duration. Notably, the inclusion of preoperative levels of GDF-15 in risk stratification models enhances their predictive value, especially when compared with those of the N-terminal prohormone of brain natriuretic peptide, which does not lead to reclassification. Thus, this review examines traditional risk assessments for cardiac surgery and the role of the novel biomarker GDF-15. This study acknowledges that the relationship between patient outcomes and elevated GDF-15 levels is not limited to CVDs or cardiac surgery but can be associated with variable diseases, including diabetes and cancer. Moreover, the normal range of GDF-15 is not well defined. Given its promise for improving patient care and outcomes in cardiovascular surgery, future research should explore the potential of GDF-15 as a biomarker for postoperative outcomes and target therapeutic intervention.

Blockade of angiotensin II modulates insulin-like growth factor 1-mediated skeletal muscle homeostasis in experimental steatohepatitis

Sarcopenia is associated with mortality in patients with nonalcoholic steatohepatitis (NASH). Angiotensin II receptor blocker (ARB) has been suggested to prevent sarcopenia, but reports on its effect on NASH-derived skeletal muscle atrophy in conjunction with insulin-like growth factor 1 (IGF-1)-mediated muscle homeostasis are few. Our aim was to examine the combined effect of the ARB losartan and IGF-1 replacement on skeletal muscle atrophy in a methionine-choline deficient (MCD) diet-fed murine steatohepatitis model. The MCD-fed mice developed steatohepatitis and skeletal muscle atrophy, as indicated by the reduction of psoas muscle mass and attenuation of forelimb and hindlimb grip strength. Significantly suppressed steatohepatitis and skeletal muscle atrophy was observed after single treatment with ARB or IGF-1, and these effects were augmented after combination treatment. Treatment with ARB and IGF-1 effectively inhibited ubiquitin proteasome-mediated protein degradation by reducing forkhead box protein O1 (FOXO1) and FOXO3a transcriptional activity in the skeletal muscle. Combined ARB and IGF-1 decreased the intramuscular expression of proinflammatory cytokines (i.e., TNFα, IL6, and IL1β) and increased the Trolox equivalent antioxidant capacity and antioxidant enzymes (CAT, GPX1, SOD2, and CYTB). This antioxidant effect was based on downregulation of NADPH oxidase (NOX) 2, normalization of mitochondrial biogenesis and dynamics. Moreover, ARB increased the hepatic and plasma IGF-1 levels and improved steatohepatitis, leading to enhanced skeletal muscle protein synthesis mediated by IGF-1/ AKT/ mechanistic target of rapamycin signaling. Collectively, combined ARB and IGF-1 replacement could be a promising new therapeutic target for NASH-derived skeletal muscle wasting.

Prevalence of osteosarcopenic obesity and related factors among Iranian older people: Bushehr Elderly Health (BEH) program

Osteosarcopenic obesity is a new syndrome that has been recently discussed in the scientific community. It is a condition that affects the elderly and involves the loss of bone, muscle, and fat tissue. The few studies that have been done on this disease showed that it has a high prevalence among the elderly and can cause various complications. This study was the first one to investigate this syndrome in Iran, and found that its prevalence was 19.83%.

BACKGROUND

Osteosarcopenic obesity syndrome (OSO) is a condition that involves osteopenia/osteoporosis, sarcopenia, and obesity. It leads to a reduction in the quality of life of the elderly and an increase in hospitalization which has attracted the attention of physicians. This study aimed to determine the prevalence and risk factors of osteosarcopenic obesity in people over 60 years of age in Bushehr.

MATERIALS AND METHODS

We used data from the Bushehr study, which included 2426 participants aged ≥ 60 years. We assessed osteoporosis/osteopenia based on T-score; sarcopenia based on hand grip strength, skeletal muscle mass index (SMI), and walking speed; and obesity based on fat mass and BMI for diagnosing OSO. We first examined the factors related to OSO in the univariable analysis and then fitted the multiple logistic regression model, separately for women and men. The result was summarized as adjusted odds ratios with a 95% confidence interval.

RESULTS

In total, 2339 elderly were examined in our study, of which 464 elderly were suffering from osteosarcopenic obesity. The standardized prevalence of OSO was 23.66% (95% CI: 21.15-26.16) in women and 18.53% (95% CI 16.35-20.87) in men. Age was positively linked to osteosarcopenic obesity in both genders and so was diabetes in men. However, education, physical activity, and protein intake were negatively linked to osteosarcopenic obesity in both genders, as well as hypertriglyceridemia and hypertension in women.

CONCLUSION

The prevalence of OSO among men and women of Bushehr city is high and is related to increasing age, low levels of education, physical activity, and protein intake among women and men.

Growth differentiation factor 15 (GDF-15) in endocrinology

Human growth differentiation factor 15 (GDF-15) is a widely distributed protein that has shown to play multiple roles in both physiological and pathological conditions. In healthy individuals, GDF-15 is mainly expressed in the placenta, followed by the prostate, although low levels of expression have also been detected in different organs. GDF-15 acts through a recently identified receptor called glial-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) which signals through the rearranged during transfection (RET) tyrosine kinase receptor. The effects of GDF-15 are pleiotropic and include appetite regulation, and actions on metabolism, pregnancy, cell survival, immune response, and inflammation. GDF-15 also plays different roles in the pathophysiology of cardiovascular disease, autoimmunity, cancer-associated anorexia/cachexia, and diabetes. In recent years, several studies have reported a link between GDF-15 and the endocrine system. In this review, we up-date and summarize the relevant investigations of the relationships between GDF-15 and different endocrine conditions. We also assess the potential pathogenic role and potential therapeutic applications of GDF-15 in the field of endocrinology.

Knockdown of growth differentiation factor-15 inhibited nonsmall cell lung cancer through inactivating PTEN/PI3K/AKT signaling pathway

BACKGROUND

Non-small cell lung cancer (NSCLC) is characterized by high morbidity and mortality in the world. Growth and differentiation factor 15 (GDF15) has been proved to play an important role in regulating tumor progression. However, the influence of GDF15 on NSCLC remains unclear.

OBJECTIVE

We aimed to investigate the regulatory role of GDF15 in NSCLC.

METHODS

The correlation between GDF15 expression and prognosis, stage of NSCLC was examined with bioinformatics method. The cell proliferation was detected with CCK8 and EdU staining. Wound healing, Transwell, flow cytometry assays were used to measure cell migration, invasion, and apoptosis, respectively.

RESULTS

High expression of GDF15 is correlated with worse survival and malignant progression of NSCLC. Knockdown of GDF15 restrained the proliferation, invasion, migration, but accelerated apoptosis of lung cancer cells through regulating PTEN/PI3K/AKT signaling pathway. sh-GDF15 suppressed epithelial mesenchymal transition (EMT) process and promoted the chemotherapy sensitivity of lung cancer cells.

CONCLUSION

GDF15 plays an important role in NSCLC progression. GDF15 mediated PTEN/PI3K/AKT signaling pathway might be the potential therapeutic targets for the prevention and treatment of GDF15.

Effect of age and gender on serum growth differentiation factor 15 and its relationship to bone density and bone turnover

Senescent cells and senescence-associated secretory phenotype (SASP) proteins are involved in age-related bone loss. Growth differentiation factor 15 (GDF 15), a stress-responsive cytokine member of the transforming growth factor-β (TGF-β) superfamily, is one of the key SASP proteins. It is strongly associated with age and higher levels correlate with frailty and are detected in several conditions and diseases. It also modulates appetite and body weight through the binding to its receptor glial cell- derived neurotrophic factor family receptor alpha- like (GFRAL) in the brainstem. The GDF 15 involvement in bone metabolism has been studied in several murine models, however, it is still unclear in humans. Therefore, this study aims to determine whether GDF 15 is associated with bone mineral density (BMD) and bone turnover, and to establish the effect of age and gender on its levels. Serum GDF 15 was measured with an ELISA from R&D Systems in 180 healthy women and men from the "XtremeCT study", divided into three age groups which represent different stages of skeletal development (16-18, 30-32, over 70 years). We also measured bone resorption marker C-terminal telopeptide of type I collagen (CTX) and bone formation markers N-terminal propeptide of type I collagen (PINP), osteocalcin (OC) and bone alkaline phosphatase (BAP) using iSYS-IDS analyser. Parathyroid hormone (PTH), 25hydroxyvitamin D (25OH-vitamin D), Insulin-like Growth Factor I (IGF-1), estradiol and testosterone were measured using the Cobas automated analyser (Roche Diagnostics). We assessed BMD at spine and total hip by dual-energy x-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HRpQCT) of the radius and tibia. Univariate analysis of variance with the post-hoc Sheffe test and multiple linear regression has been used to assess the effect of age and gender. Spearman's rank correlation was used to evaluate the associations between GDF 15 and the other variables. We found GDF 15 levels significantly associated with age (p < 0.001) and gender (p = 0.008), with a significant gender ∗ age interaction (p < 0.001). Significantly higher levels of GDF 15 were found in subjects aged over 70 compared with the younger people (p < 0.001) and significantly higher levels were detected in men. We did not find any significant correlation between GDF 15 and bone turnover markers (BTMs), BMD, HRpQCT measures and hormones in any of the age groups. In conclusion, age and gender are determinants of GDF15 and much higher levels are found in older people and in men. Since no association was found between GDF 15 and bone health measures, we hypothesize that the effect of GDF 15 on bone might be exert by other tissue, such as muscle.

The search for systemic biomarkers for monitoring degenerative lumbar spinal disorders

Objectives

In our previous study, we reported that low back pain (LBP) severity and disability significantly correlate with body composition and several blood biochemical factors. Herein, we tested the hypothesis that these covariates are associated with anatomical deformations of the lumbar spine, in particular, radiographic facet joint osteoarthritis (FJOA) and lumbar disc degeneration (LDD) features important contributors to LBP.

Methods

CT and MRI images of the lumbar spine were obtained from 200 individuals suffering from LBP-sciatica. We examined the FJOA and total LDD score - the sum of the scores of the three radiographic features (intervertebral disc herniation, osteophythosis and spondylolisthesis) at the L1 - S1 vertebral levels. By implementing a bioelectrical impedance analysis, we assessed the participants for body composition, specifically, extracellular water (ECW). Plasma levels of growth and differentiation factor 15 (GDF-15) and visceral adipose tissue-derived serine protease inhibitor (vaspin), were detected by ELISA.

Results

By conducting a series of multivariable regression analyses, we report that the circulating levels of GDF-15, vaspin, and ECW are significantly and independently associated with FJOA scores [β_GDF15 ​= ​0.38 ​± ​0.08, p ​= ​0.0001; β_VASPIN ​= ​0.36 ​± ​0.07, p ​= ​0.000004; β_ECW ​= ​0.24 ​± ​0.07, p ​= ​0.002]. The levels of GDF-15 (β ​= ​0.30 ​± ​0.10, p ​= ​0.007) and ECW (β ​= ​0.20 ​± ​0.09, p ​= ​0.03) were also found significantly associated with the LDD scores.

Conclusion

The obtained new data suggest that GDF-15, vaspin and ECW may serve as biomarkers for FJOA and LDD phenotypes.

Growth Differentiation Factor-15 as a Biomarker for Sarcopenia in Patients With Chronic Obstructive Pulmonary Disease

Purpose

Sarcopenia is an important factor contributing to comorbidities in patients with chronic obstructive pulmonary disease (COPD) and is an independent risk factor for increased mortality. The diagnostic process for sarcopenia requires specific equipment and specialized training and is difficult procedurally. A previous study found that GDF15 levels are associated with skeletal muscle mass and function in patients with COPD. However, whether circulating GDF15 levels can be used for the prediction of sarcopenia in patients with COPD is unknown.

Methods

This study included 235 patients with stable COPD who were divided into a development set (n = 117) and a validation set (n = 118), and we followed the definition of sarcopenia as defined by the guidelines from the Asian Working Group for Sarcopenia. Serum concentrations of GDF15 were measured using an enzyme-linked immunosorbent assay (ELISA), and construction of a nomogram and decision curve analysis were performed using the R package “rms.”

Results

In this study, serum GDF15 levels were negatively associated with skeletal muscle mass (r = –0.204, p = 0.031), handgrip strength (r = –0.274, p = 0.004), quadriceps strength (r = –0.269, p = 0.029), and the thickness (r = –0.338, p < 0.001) and area (r = –0.335, p < 0.001) of the rectus femoris muscle in patients with COPD. Furthermore, the serum levels of GDF15 in patients with sarcopenia were significantly higher than those in controls. Importantly, serum levels of GDF15 could effectively predict sarcopenia in patients with COPD based on the development set (AUC = 0.827) and validation set (AUC = 0.801). Finally, a nomogram model based on serum GDF15 levels and clinical features showed good predictive ability (AUC > 0.89) in the development and validation sets.

Conclusion

Serum GDF15 levels could be used to accurately and easily evaluate sarcopenia in patients with COPD.

Osteosarcopenic obesity and its components-osteoporosis, sarcopenia, and obesity-are associated with blood cell count-derived inflammation indices in older Chinese people

Background

The aim of this study was to investigate the associations of osteosarcopenic obesity (OSO) and its components with complete blood cell count-derived inflammation indices.

Methods

In this cross-sectional study, data of 648 participants aged ≥60 years (men/women: 232/416, mean age: 67.21 ± 6.40 years) were collected from January 2018 to December 2020. Areal bone mineral density and body fat percentage were used to define osteopenia/osteoporosis and obesity, respectively. The criteria of the 2019 Asian Working Group for Sarcopenia were used to diagnose sarcopenia. Based on the number of these conditions, participants were divided into four groups: OSO/0, OSO/1, OSO/2, and OSO/3. Logistic regression analysis was conducted to identify associations between blood cell count-derived inflammation indices and the number of disorders with abnormal body composition.

Results

Systemic inflammation response index (SIRI), white blood cells, neutrophil-to-lymphocyte ratio (NLR), aggregate inflammation systemic index (AISI), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) showed statistically significant differences among the four groups (P < 0.05). Unlike in the OSO/0 group, in all other groups, AISI, SIRI, PLR, and NLR were significantly associated with increased likelihood of having multiple disorders with abnormal body composition after adjustment for confounders (P < 0.0001 for all). However, LMR showed an inverse correlation with the number of these conditions (P < 0.05).

Conclusion

Higher SIRI, AISI, NLR, and PLR values and lower LMR values are closely associated with OSO and its individual components—osteoporosis, sarcopenia, and obesity—in older adults, suggesting that the value of these indices in the evaluation of OSO warrants further investigation.

Growth differentiation factor-15 as a modulator of bone and muscle metabolism

This study aims to clarify the potential role of growth differentiation factor-15 (GDF-15) as a myokine in bone metabolism and muscle function in females with osteoporosis. In total, 45 female participants (71.0 ± 8.5 years) with distal radius fractures were recruited. Participants were classified as healthy/osteopenic (n = 28) (CON) or osteoporotic (n = 17) (OP) according to their T-score from the areal bone mineral density (aBMD) of the femoral neck. Body mass index, upper arm and calf circumferences, and handgrip strength were assessed. Total hip, femoral neck, and lumbar spine aBMD was measured via dual-energy x-ray absorptiometry. The focal bone quality of the distal radius was evaluated via 3D reconstructed computed tomographic images. Serum levels of GDF-15, insulin-like growth factor-1, and inflammatory markers such as tumor necrosis factor-α (TNF-α), interleukin-6, and interleukin-1β (IL-1β), as well as the corresponding mRNA levels in the pronator quadratus muscle were determined. Participants in the OP group had higher serum GDF-15 levels than those in the CON group. The mRNA levels of GDF-15, IL-1β, and TNF-α in the pronator quadratus muscle were significantly higher in the OP group than in the CON one. Levels of both serum GDF-15 and GDF-15 mRNA in muscle were positively correlated with age and negatively associated with the aBMD of the total hip and focal bone quality of the distal radius. Handgrip power was not correlated with circulating GDF-15 levels but was correlated with circumferences of the upper arm and calf, and levels of GDF-15 mRNA in muscle specimens. The mRNA levels of GDF-15 were correlated with those of inflammatory cytokines such as TNF-α and IL-1β. The mRNA levels of TNF-α were associated with circumferences of the upper arm and calf and with the aBMD of the total hip. The mRNA levels of GDF-15 in muscle were correlated with serum levels of GDF-15 and TNF-α. GDF-15 may have associations with bone metabolism in humans via paracrinological and endocrinological mechanisms. Maintenance of muscle mass and function would be influenced more by GDF-15 in muscle than by circulating GDF-15. The role of GDF-15 in bone metabolism and muscle homeostasis could be related to inflammatory responses.