Abu-Lebdeh, Haitham S.

Abstract Disclosure: H.M. Heshmati: None. H.S. Abu-Lebdeh: None. Background: Growth differentiation factor 15 (GDF15) is a peptide hormone produced by the placenta during pregnancy and by several other organs (e.g., prostate, bladder, kidney, pancreas, and endometrium). It is a member of the transforming growth factor-β superfamily. The gene encoding for GDF15 is located on chromosome 19. The mature GDF15 has 112 amino acids and binds to glial cell-derived neurotrophic factor family receptor alpha-like. GDF15 is involved in the maintenance of homeostasis and contributes to the pathogenesis of several medical conditions. This literature analysis provides an update on the relevance of GDF15 in health and few selected diseases. Methods: A systematic search of literature was conducted using the search terms growth differentiation factor 15, pregnancy, heart failure, anorexia, obesity, diabetes, and cancer. Results: In control subjects, the median serum GDF15 level is around 680 pg/mL and increases with aging. There is an increase in GDF15 secretion during pregnancy (third trimester serum levels > 20,000 pg/mL) and under other stressful conditions such as inflammation, myocardial ischemia, pulmonary diseases, diabetes, and cancer. GDF15 is involved in the maintenance of cell and tissue homeostasis. It has anti-inflammatory, immunomodulatory, and anorectic properties. The high serum GDF15 levels observed during pregnancy plays an important role in the feto-maternal immunotolerance. Low serum GDF15 levels have been reported in pregnancies with complications (e.g., preeclampsia and miscarriage). Serum GDF15 levels are negatively correlated with body mass index. Treatment with metformin in patients with or without type 2 diabetes stimulates GDF15 production, and this can explain, at least in part, the weight-loss property of metformin. In patients with heart failure or cancer, the increased serum GDF15 levels contribute to cachexia (anorexia and weight loss). Serum GDF15 level has the potential to be used as a biomarker for disease diagnosis and prognosis (e.g., biomarker for heart failure and pancreatic cancer). High serum GDF15 levels are associated with poor prognosis and predict all-cause mortality. Based on the GDF15 properties related to appetite and body weight control, GDF15 analogs and antagonists can be considered in the weight management of various conditions such as obesity (induction of anorexia with GDF15 analogs), and heart failure or cancer (reduction of cachexia with GDF15 antagonists). Conclusion: GDF15, a hormone synthesized by several organs including placenta, prostate, bladder, kidney, pancreas, and endometrium, has an important role in multiple physiological and pathological conditions. Its serum level can be considered as a biomarker for the diagnosis and prognosis of several diseases. GDF15 analogs and antagonists have the potential to be used in the weight management of obesity and cardiac or cancer cachexia. Presentation: Sunday, July 13, 2025

Abstract Disclosure: H.M. Heshmati: None. H.S. Abu-Lebdeh: None. Background: Fibroblast growth factor 21 (FGF21), a member of the human FGF superfamily, is a 181 amino acid peptide hormone primarily produced by the liver. The gene of FGF21, located on chromosome 19, was cloned in 2000. FGF21 is involved in the maintenance of metabolic homeostasis. This review presents an update on the relevance of FGF21 in the diagnosis and treatment of metabolic disorders including obesity, nonalcoholic fatty liver disease (NAFLD), dyslipidemia, and type 2 diabetes. Methods: A systematic search of literature was conducted using the search terms fibroblast growth factor 21, obesity, nonalcoholic fatty liver disease, dyslipidemia, and type 2 diabetes. Results: FGF21 is a stress hormone with effects on energy expenditure and metabolism of lipids and glucose. FGF21 exerts its endocrine action in the central nervous system and adipose tissue. The serum FGF21 levels in normal subjects increase with aging. Stressful conditions (e.g., fasting status, protein restriction, exercise, metabolic disorders, kidney diseases, cardiovascular diseases, and sepsis) increase FGF21 secretion. Serum FGF21 levels are increased in obesity, NAFLD, dyslipidemia, and type 2 diabetes. Some of these patients may have a state of FGF21 resistance. The resistance to FGF21 is related, at least in part, to the presence of high circulating levels of fibroblast activation protein, a protease that inactivates FGF21. It has been suggested that the exercise-induced weight loss can be due to increased FGF21 secretion and decreased FGF21 resistance in adipose tissue. Serum FGF21 level has the potential to be used as a biomarker for early diagnosis of metabolic disorders (e.g., NAFLD and type 2 diabetes). Based on different metabolic properties of FGF21, FGF21-based therapy has been considered as an attractive approach for the treatment of metabolic disorders. Since native FGF21 has poor pharmacodynamic properties (e.g., short half-life and proteolytic cleavage by proteases), long-acting FGF21 analogs (e.g., LY2405319, PF-05231023, pegozafermin, AKR-001, and LLF580) have been synthesized and tested in clinical trials for the treatment of obesity, NAFLD, dyslipidemia, and type 2 diabetes. The available results show that FGF21 analogs can reduce body weight, liver fat, blood lipids, and fasting insulin/insulin resistance. Overall, the treatment with these analogs is safe and well tolerated. Conclusion: FGF21 is a predominantly liver-derived peptide hormone regulating energy expenditure and metabolism of lipids and glucose. Serum FGF21 levels are increased in several metabolic disorders including obesity, NAFLD, dyslipidemia, and type 2 diabetes. FGF21 is an attractive target for the treatment of these metabolic disorders. Despite some promising results observed with the use of FGF21 analogs, more clinical studies are needed before recommending FGF21-based therapies in metabolic disorders. Presentation: 6/2/2024

Abstract Disclosure: H.S. Abu-Lebdeh: None. H.M. Heshmati: None. Background: Prostate cancer is among the most common malignancy in men and represents the second most common cause of cancer-related mortality among men in the US. Androgen-deprivation therapy with surgical or medical castration is widely used to treat hormone-sensitive prostate cancer. Disease progression despite androgen-deprivation therapy is a state defined as castration-resistant prostate cancer that is associated with poor survival rate. This review presents an update on the contribution of two adrenal androgens, 11-ketotestosterone and 11-ketodihydrotestosterone, to the castration-resistant prostate cancer. Methods: A systematic search of literature was conducted using the search terms prostate cancer, testosterone, dihydrotestosterone, adrenal androgens, 11-ketotestosterone, 11-ketodihydrotestosterone, androgen-deprivation therapy, castration, and castration-resistant prostate cancer. Results: In 2022, around 268,490 new cases of prostate cancer were diagnosed in the US with a mortality of 34,500 cases. Although androgen-deprivation therapy with castration is efficient at the beginning, most patients develop a state of castration resistance usually after 2-3 years as a result of the reactivation of androgen-receptor signaling despite low testosterone levels. The adrenal glands produce significant amounts of steroid hormones and metabolites. Among them, 11-ketotestosterone and 11-ketodihydrotestosterone are potent and efficacious androgens with potentially longer activity compared to testosterone and dihydrotestosterone because they are metabolized at a lower rate. Dihydrotestosterone derived from the metabolism of adrenal androgens (e.g., androstenedione and dehydroepiandrosterone) and especially 11-ketotestosterone and 11-ketodihydrotestosterone are important contributors to castration-resistant prostate cancer. In these cases, adrenal suppression with drugs causing a decrease in adrenal androgen production may improve the effectiveness of the androgen-deprivation therapy. Conclusion: In most patients with prostate cancer, androgen-deprivation therapy loses its effectiveness after 2-3 years leading to a state of castration-resistant prostate cancer. Two potent and highly efficacious androgen-receptor agonists of adrenal origin, 11-ketotestosterone and 11-ketodihydrotestosterone, are predominant androgens after castration and play an important role in the development and progression of castration-resistant prostate cancer. Their measurement in blood can be of clinical value during androgen-deprivation therapy. Concomitant treatment aimed to block the production of adrenal androgens is of potential interest in the management of these patients, but more studies are necessary to further investigate the benefits and adverse effects of this approach. Presentation: Saturday, June 17, 2023

Background Elevated lipoprotein(a) [Lp(a)] levels have been associated with the presence of atherosclerotic disease. However, the results of prospective studies of Lp(a) and cardiovascular disease have been contradictory. Methods and Results From 1968 through 1982, lipoprotein analysis was performed in 11 335 Olmsted County residents. Quantitative cholesterol and triglycerides were obtained along with semiquantitative Lp(a) levels based on electrophoretic pattern. Lp(a) bands were scored from 0 (absent) to 3 (increased). A cohort of 4967 men and 4968 women with no prior history of atherosclerotic disease who had baseline Lp(a) determinations were followed up for 14 years for development of coronary artery disease (CAD) and cerebrovascular disease (CVD). During 131 330 person-years of follow-up, there were 1848 CAD events and 841 CVD events. Age, diabetes, hypertension, cholesterol, and triglycerides were significantly and independently associated with an increased risk of CAD and CVD in men and women. There was a significant increase in the adjusted hazards ratio for CAD with increasing Lp(a) levels for men and women. For Lp(a) level 3, the hazard ratio was 1.9 (range, 1.3 to 2.9) in women and 1.6 (range, 1.0 to 2.5) in men. The adjusted hazard ratio for CVD showed an irregular association with Lp(a) levels in men and no association in women. Conclusions In this cohort of 9936 men and women initially free of cardiovascular disease who were followed up for 14 years, Lp(a) was a significant predictor of risk of future CAD. Lp(a) was a weak risk factor for CVD in men and was not a significant predictor of CVD risk in women.

Abstract Context: The association between acute pancreatitis and primary hyperparathyroidism (PHPT) is controversial. Objective: The aim of the study was to address the incidence and disease characteristics of acute pancreatitis in PHPT from a large inception cohort of community residents. Design and Setting: Patients with acute pancreatitis were identified in an Olmsted County, Minnesota, cohort of PHPT subjects diagnosed from 1965–2001 and compared to matched control subjects. Main Outcome Measures: The estimated rate of developing acute pancreatitis was calculated by person-years method. Cox models assessed the effect of PHPT disease status on the development of acute pancreatitis. Results: Of 684 patients with PHPT, 10 patients (1.5%) developed acute pancreatitis, compared to 32 of 1364 control patients (2.3%). The estimated rate of development of acute pancreatitis in PHPT was 114 per 100,000 person-years, compared to 140 per 100,000 person-years in control subjects (P = 0.56). The estimated hazard ratio of acute pancreatitis for PHPT relative to the control subjects was 0.84 (P = 0.89). The majority of subjects with PHPT and acute pancreatitis were women (n = 7), and the mean age was 70.6 yr at the time of acute pancreatitis. PHPT was present an average of 137 months before the development of acute pancreatitis, and contributing causes for acute pancreatitis were in identified in four patients. Maximal serum calcium levels in PHPT were not significantly associated with the development of acute pancreatitis. Conclusions: Acute pancreatitis was not increased in community patients with PHPT, and therefore, there does not appear to be a causal relationship between PHPT and acute pancreatitis.