Adrenomedullin Concentrations Research Articles

High Serum Adrenomedullin and Mid-Regional Pro-Atrial Natriuretic Peptide Concentrations in Early Pregnancy Predict the Development of Gestational Hypertension.

Adrenomedullin (AM) and natriuretic peptide levels are elevated in pre-eclampsia. The aim of the present study was to determine AM and natriuretic peptide concentrations before 20 weeks of pregnancy in women who later developed gestational hypertension and in normal pregnancies. 95 pregnant Caucasian women were included in the study. Gestational hypertension (GH) was diagnosed in 18 patients. The control group consisted of 41 patients with normal pregnancies (non-GH). Blood samples were taken during the first trimester of pregnancy. Analysis of NT-proBNP showed no significant differences between the group of patients who later developed GH and those with normal pregnancies. Patients who developed GH later in pregnancy had higher levels of both MR-proANP (p < 0.001) and adrenomedullin (p < 0.001). Higher levels of MR-proANP were found in the GH with pre-eclampsia group compared with the GH without pre-eclampsia group. Higher levels of AM (p < 0.05) and MR-proANP (p < 0.005) correlated with the risk of preterm birth. (1) Plasma adrenomedullin and MR-proANP concentrations were higher before the 20th week of pregnancy in women who later developed GH; (2) NT-proBNP concentrations did not differ between women with pregnancy-induced hypertension and normal pregnancies; (3) MR-proANP concentrations were highest in patients who developed pre-eclampsia in advanced pregnancy; and (4) there was a correlation between higher plasma adrenomedullin, MR-proANP concentrations before the 20th week of pregnancy, and the risk of preterm birth.

Bioactive Adrenomedullin in Dogs with Sepsis and Septic Shock: A Prospective, Case-Control Study.

Sepsis and septic shock are leading causes of morbidity and mortality in both humans and dogs, and early diagnosis is crucial for improving outcomes. This study aimed to evaluate bioactive adrenomedullin (bio-ADM) concentrations in dogs with septic shock (n = 25), dogs with sepsis without evidence of shock (n = 25), and healthy control dogs (n = 25). Plasma bio-ADM concentrations were measured using a human sandwich enzyme-linked immunosorbent assay and reported as median (interquartile range). Plasma bio-ADM concentrations were significantly higher in both septic groups compared to the healthy controls (all <22.4 pg/mL), but not significantly different between the septic shock (75.0 [28.7-115.0] pg/mL) and sepsis (30.7 [22.4-79.7] pg/mL) groups. Dogs with higher illness severity scores had significantly higher bio-ADM concentrations (93.1 [32.2-122.0] pg/mL) than those with lower scores (29.8 [22.4-71.2] pg/mL). However, bio-ADM concentrations did not differ between survivors (33.0 [22.7-76.7] pg/mL) and non-survivors (74.7 [26.1-123.2] pg/mL). Measurement of bio-ADM is a potential marker for canine sepsis, but not for the identification of septic shock, and may provide information on disease severity. Further studies, including those on non-infectious inflammatory conditions, are necessary to better understand the diagnostic utility of bio-ADM measurement and its potential role as a marker of treatment response in dogs with sepsis.

Peptidylglycine α-amidating monooxygenase and adrenomedullin measurement in patients with hepatic cirrhosis.

Background: Peptidylglycine α-amidating monooxygenase (PAM) is an enzyme involved in the maturation of regulatory peptides. Here we examined PAM activity and adrenomedullin (bio-ADM) concentrations in patients with hepatic cirrhosis and determined net changes across the liver, kidneys and leg. Materials&methods: A total of 48 patients with hepatic cirrhosis and 16 control subjects were included. All patients and controls underwent an invasive procedure with blood collected across organs. Results: PAM activity was increased in cirrhotic patients but without a net change across the liver, leg or kidney. In contrast, bio-ADM concentrations were associated with severity of disease and found to be higher in venous blood from the liver. Conclusion: Increased PAM activity in patients with hepatic cirrhosis may reflect other organs involved in cirrhotic disease.

Higher serum adrenomedullin concentration is associated with an increased risk of gestational diabetes mellitus: A nested case-control study in Wuhan, China

Adrenomedullin (ADM) is thought to play a significant role in regulating insulin secretion and glucose metabolism. However, studies on the relationship between ADM and gestational diabetes mellitus (GDM) are limited. We hypothesized that a higher serum ADM concentration would be associated with an increased risk of GDM. Therefore, a nested case-control study of 65 GDM cases and 130 prepregnancy body mass index, age, parity, and gestational age of blood collection-matched controls was conducted to prospectively evaluate the association between circulating ADM concentrations in early pregnancy and the risk of GDM in pregnant women based on the Tongji Birth Cohort. Serum ADM concentrations in the GDM group were higher than those in the control group (2125.04 ± 644.97 vs 1880.76 ± 581.13 pg/mL) (P = .008). Serum ADM concentration was positively associated with the risk of developing GDM (Ptrend < .05). The adjusted odds ratio (OR) comparing the highest tertile of ADM with the lowest was 2.74 (95% CI, 1.17-6.43). The risk of GDM increased by 49% (OR, 1.49; 95% CI, 1.05-2.12) for each SD increment of serum ADM. Moreover, serum ADM concentration was positively correlated with circulating total cholesterol (r = 0.204), triglycerides (r = 0.197), and systolic blood pressure (r = 0.173), but negatively correlated with circulating high-density lipoprotein cholesterol concentration (r = –0.176). Pregnant women with higher serum ADM concentrations have a markedly increased risk of developing GDM. Further studies are warranted to explore the possible thresholds of ADM that increase the risk of GDM and to confirm and elucidate the underlying mechanisms.

Plasma Clearance of Intravenously Infused Adrenomedullin in Rats with Acute Renal Failure.

Plasma adrenomedullin concentrations are reportedly elevated in patients with renal failure; however, the underlying mechanism is unclear. In this study, we investigated the plasma clearance of synthetic human adrenomedullin (AM) in two models of rats with renal dysfunction; one was induced by subcutaneous injection of mercury chloride (RD-Ag) and the other by completely blocking bilateral renal blood flow (RD-Bl). Sixty minutes after starting intravenous AM infusion, AM levels in RD-Ag, RD-Bl, and rats with normal renal function (NF) were still increased slightly; however, plasma AM levels in RD-Ag rats were approximately three times as high as in RD-Bl and NF rats. Plasma AM disappearance after the end of treatment was similar among the three groups. Pharmacokinetic analysis revealed that elevated plasma AM in RD-Ag rats may be caused by a reduced volume of distribution. The adrenomedullin functional receptor is composed of heterodimers, including GPCR, CLR (calcitonin receptor-like receptor, CALCRL), and the single transmembrane proteins, RAMP2 or RAMP3 (receptor activity modifying protein). Calcrl expression was downregulated in the lungs and kidneys of RD-Ag rats. Furthermore, the plasma concentration of exogenous AM was elevated in mice deficient in vascular endothelium-specific Ramp2. These results suggest that decreased plasma AM clearance in RD-Ag is not due to impaired renal excretion but to a decreased volume of distribution caused by a reduction in adrenomedullin receptors.

Associations of Plasma Bioactive Adrenomedullin Levels with Cardiovascular Risk Factors in BRCA1/2 Mutation Carriers

Background Cardiovascular disease (CVD) is an important cause of morbidity and mortality in breast cancer survivors. Effective screening modalities to identify CVD risk are lacking in this population. Adrenomedullin (ADM) has been suggested as a biomarker for subclinical cardiac dysfunction in the general population. Levels of ADM have been proven to be responsive to lifestyle changes that lead to improved cardiovascular health. As BRCA1/2 mutation carriers are deemed to be at an increased risk for CVD, the aim of this study was to examine plasma ADM levels in a cohort of BRCA mutation carriers and to assess their association with cardiovascular risk factors. Methods Plasma ADM concentrations were measured in 292 female BRCA1/2 mutation carriers with and without a history of breast cancer. Subjects were classified into high versus low ADM levels based on the median ADM level in the entire cohort (13.8 pg/mL). Logistic regression models were used to estimate the odds ratios (OR) of having elevated ADM levels by several cardiovascular risk factors. Results Of all women (median age: 43 years), 57.5% had a previous diagnosis of breast cancer. The median time between diagnosis and study entry was three years (range: 0 – 32 years). Women presenting with metabolic syndrome had 22-fold increased odds of having elevated ADM levels (p < 0.001). Elevated ADM levels were associated with lower cardiorespiratory fitness (OR = 0.88, p < 0.001) and several parameters of obesity (p < 0.001). ADM levels were higher in women who have ever smoked (OR = 1.72, p = 0.02). ADM levels were not associated with a previous diagnosis of breast cancer (p = 0.28). Conclusions This is the first study in BRCA mutation carriers that has linked circulating ADM levels to traditional cardiovascular risk factors. The long-term clinical implications of these findings are yet to be determined.

Relationship Between Serum Concentration of Adrenomedullin and Myocardial Ischemic T Wave Changes in Patients With Lung Cancer.

BackgroundPatients with lung cancer are at increased risk for the development of cardiovascular diseases. Molecular markers for early diagnosis of cardiac ischemia are of great significance for the early prevention of cardiovascular events in patients with lung cancer. By evaluating the relationship between adrenomedullin (ADM) and myocardial ischemic T wave changes, the clinical value of circulating ADM as a predictor of myocardial ischemia in patients with lung cancer is confirmed.MethodsWe enrolled patients with lung cancer and healthy people from 2019 to 2021 and extracted a detailed ECG parameter. After adjustment for potential confounders, logistic regression was used to assess the association of clinical data. We performed analyses on differences in T wave between patients with lung cancer and healthy people, and the relationship between T wave and ADM among patients with lung cancer. Receiver operator characteristic (ROC) curves were drawn to confirm the diagnostic value of biomarkers.ResultsAfter adjusting for potential confounders, the incidence of T wave inversion or flattening in patients with lung cancer was higher than in healthy people (OR: 3.3228, P = 0.02). Also, further analysis of the data of lung cancer patients revealed that the ADM in lung cancer patients with T wave inversion or flat was higher than those with normal T wave (189.8 ± 51.9 vs. 131.9 ± 38.4, p < 0.001). The area under the ROC curve was 0.8137.ConclusionAmong the patients with lung cancer, serum ADM concentration is associated with the incidence of the abnormal T wave. ADM might be a potentially valuable predictor for heart ischemia in patients with lung cancer.

Single-dose of adrecizumab versus placebo in acute cardiogenic shock (ACCOST-HH): an investigator-initiated, randomised, double-blinded, placebo-controlled, multicentre trial

Cardiogenic shock has a high mortality on optimal therapy. Adrenomedullin is released during cardiogenic shock and is involved in its pathophysiological processes. This study assessed treatment with the humanised, monoclonal, non-neutralising, adrenomedullin antibody adrecizumab, increasing circulating concentrations of adrenomedullin in cardiogenic shock. In this investigator-initiated, placebo-controlled, double-blind, multicentre, randomised trial (ACCOST-HH), patients were recruited from four university hospitals in Germany. Patients were eligible if they were 18 years old or older and hospitalised for cardiogenic shock within the last 48 h. Exclusion criteria were resuscitation for longer than 60 min and cardiogenic shock due to sustained ventricular tachycardia or bradycardia. Adult patients in cardiogenic shock were randomly assigned (1:1) to intravenous adrecizumab (8 mg/kg bodyweight) or placebo using an internet-based software. A block randomisation procedure was applied with stratification by age (older vs younger than 65 years), sex (male vs female), and type of underlying cardiogenic shock (acute myocardial infarction vs other entities). Investigators, patients, and medical staff involved in patient care were masked to group assignment. The primary endpoint was number of days up to day 30 without the need for cardiovascular organ support, defined as vasopressor therapy, inotropes, or mechanical circulatory support (or both) assessed in the intention-to-treat population. Safety outcomes included therapy-emergent serious adverse events, severe adverse events, adverse events, suspected unexpected serious adverse reactions, study drug-related mortality, and total mortality. The trial was registered at ClinicalTrials.gov, NCT03989531, and EudraCT, 2018-002824-17, and is now complete. Between April 5, 2019, and Jan 13, 2021, 150 patients were enrolled: 77 (51%) were randomly assigned to adrecizumab and 73 (49%) to placebo. All patients received the allocated treatment. The number of days without the need for cardiovascular organ support was not different between patients receiving adrecizumab or placebo (12·37 days [95% CI 9·80-14·94] vs 14·05 [11·41-16·69]; adjusted mean difference -1·69 days [-5·37 to 2·00]; p=0·37). Serious adverse events occurred in 59 patients receiving adrecizumab and in 57 receiving placebo (odds ratio 0·92 [95% CI 0·43-1·98]; p=0·83). Mortality was not different between groups at 30 days (hazard ratio 0·99 [95% CI 0·60-1·65]; p=0·98) or 90 days (1·10 [0·68-1·77]; p=0·71). Adrecizumab was well tolerated in patients with cardiogenic shock but did not reduce the need for cardiovascular organ support or improve survival at days 30 and 90. Adrenomed AG and University Hospital of Hamburg.

Serum level of Adrenomedullin in patients with primary knee osteoarthritis; relation to disease severity

BackgroundAdrenomedullin (AM) is a peptide which was suggested to be involved in the pathogenesis of osteoarthritis through its anti-inflammatory and anti-apoptotic effect. AM was found to be elevated in some inflammatory rheumatic diseases as rheumatoid arthritis and ankylosing spondylitis.The current study was performed to measure serum Adrenomodullin (AM) concentrations in patients with primary knee osteoarthritis (KOA) and to assess association with severity of the disease. The study was performed on 50 patients with primary KOA diagnosed according to American College of Rheumatology (ACR) Revised Criteria for Early Diagnosis of Knee Osteoarthritis and 20 age- and sex-matched controls with no clinical features of KOA. The Kellgren and Lawrence (KL) classification was used to evaluate the disease severity of knee OA. Disease activity was assessed by The Western Ontario and McMaster Universities Arthritis Index (WOMAC). Blood samples had been collected from patients with OA and controls for assessing Adrenomodullin in patients’ sera by ELISA.ResultsThere were a significant increase in serum Adrenomedullin concentrations in KOA patients compared to controls (10.64 ±19.2 ng/ml vs. 1.39 ±1.6 ng/ml in cases and controls respectively) (p value = 0.036). There was positive significant correlation of serum Adrenomedullin levels with KL grades (r=0.608, p value <0.001). OA patients with VAS score >6 have significantly higher serum Adrenomedullin levels than OA patients with VAS Score <6. No detected significant correlation between any of (patients’ age, BMI, disease duration, tenderness score, and WOMAC score) with serum Adrenomedullin levels among studied OA cases (p values >0.05).ConclusionThis study concluded that serum Adrenomedullin (AM) level is elevated in patients with KOA and is positively correlated with the severity of disease.

Promotion of vascular integrity in sepsis through modulation of bioactive adrenomedullin and dipeptidyl peptidase 3.

Sepsis represents one of the major medical challenges of the 21st century. Despite substantial improvements in the knowledge on pathophysiological mechanisms, this has so far not translated into novel adjuvant treatment strategies for sepsis. In sepsis, both vascular tone and vascular integrity are compromised, and contribute to the development of shock, which is strongly related to the development of organ dysfunction and mortality. In this review, we focus on dipeptidyl peptidase 3 (DPP3) and adrenomedullin (ADM), two molecules that act on the vasculature and are involved in the pathophysiology of sepsis and septic shock. DPP3 is an ubiquitous cytosolic enzyme involved in the degradation of several important signalling molecules essential for regulation of vascular tone, including angiotensin II. ADM is a key hormone involved in the regulation of vascular tone and endothelial barrier function. Previous studies have shown that circulating concentrations of both DPP3 and ADM are independently associated with the development of organ failure and adverse outcome in sepsis. We now discuss new evidence illustrating that these molecules indeed represent two distinct pathways involved in the development of septic shock. Recently, both ADM‐enhancing therapies aimed at improving endothelial barrier function and vascular tone and DPP3‐blocking therapies aimed at restoring systemic angiotensin responses have been shown to improve outcome in various preclinical sepsis models. Given the current lack of effective adjuvant therapies in sepsis, additional research on the therapeutic application of these peptides in humans is highly warranted.

Increased concentrations of bioactive adrenomedullin subsequently to angiotensin-receptor/neprilysin-inhibitor treatment in chronic systolic heart failure.

AimsThe clinically investigated rationale for neprilysin (NEP)‐inhibition by angiotensinreceptor‐NEPinhibitor (ARNi) therapy is to induce elevations in endogenous natriuretic peptides. NEP, however, cleaves a broad spectrum of substrates, which partially hold significant implications in heart failure with reduced ejection fraction (HFrEF). The effect of NEP inhibition on these peptides has not been investigated thoroughly. This study explored the response of adrenomedullin (ADM) regulation to the initiation of ARNi.MethodsSeventy‐four patients with stable HFrEF and initiation of ARNi were prospectively enrolled, 67 patients on continuous angiotensin‐converting‐enzyme inhibitor(ACEi)/angiotensin‐receptor blocker (ARB) therapy served as control. Plasma bioactive‐ADM (bio‐ADM), mid‐regional‐pro‐ADM (MR‐proADM), B‐typenatriuretic peptide (BNP) and N‐terminal‐pro‐BNP (NT‐proBNP) were determined at baseline, short‐term, 1‐year and 2‐year follow up.ResultsFollowing ARNi initiation both bio‐ADM and MR‐proADM concentrations were significantly increased at early and long‐term follow up (bio‐ADM [pg/mL]: 26.0 [interquartile range {IQR}: 17.7–37.5] vs. 50.8 [IQR: 36.5–78.1] vs. 54.6 [IQR: 42.0–97.1] vs. 57.4 [IQR: 48.5–161.6]; MR‐proADM [nmol/L]: 0.87 [IQR: 0.64–1.12] vs. 1.25 [IQR: 0.93–1.79] vs. 1.42 [IQR: 0.95–1.90] vs. 1.60 [IQR: 1.12–2.46], P < .0001 for all). The ratios bio‐ADM/MR‐proADM and BNP/NT‐proBNP increased during ARNi‐therapy proving improved availability of bioactive peptides. The proportional increase of bio‐ADM markedly exceeded BNP increase. Patients converted to ARNi showed similar biomarker patterns irrespective of baseline renin–angiotensin system blocker therapy, i.e. ACEi or ARB (P > .05 for all), indicating that activation of the ADM‐axis arises particularly from NEPinhibition.ConclusionThe significant increase of MR‐proADM and bio‐ADM together with an elevated bioADM/MR‐proADM ratio suggest both enhanced formation and reduced breakdown of bioactive ADM following the initiation of ARNi. Activation of the ADM‐axis represents a so far unrecognized effect of ARNi.

Abstract P6-10-16: High circulating levels of adrenomedullin are associated with metabolic syndrome and low cardiorespiratory fitness in BRCA1 and BRCA2 mutation carriers

Abstract BACKGROUND: Risk factors for cardiovascular disease (CVD) and breast cancer overlap substantially. Identification of the underlying mechanisms associated with this co-occurrence is of great public health importance. Adrenomedullin (AM) is an almost ubiquitously expressed peptide with vasodilator and natriuretic properties. Previous studies have observed a link between high AM levels and worse prognosis in patients with myocardial infarction and heart failure, indicating a crucial role in the pathophysiology of CVD. Moreover, AM is expressed in 80% of sporadic breast cancers, and the degree of expression is associated with tumour growth, local tumour progression and bone metastases. High plasma AM levels are linked to arterial hypertension, diabetes, obesity and smoking. Preliminary evidence suggests that AM influences the osteoclast differentiation mediated by Receptor Activator of NF-κB Ligand (RANKL), an important signalling pathway in BRCA1-associated breast tumorigenesis. OBJECTIVE: Besides an elevated risk of breast cancer, recent studies revealed that BRCA mutation carriers are potentially at higher cardiovascular risk. The value of AM in BRCA mutation carriers is unknown. The aim of this study was to examine circulating plasma AM levels in BRCA mutation carriers and assess their association with modifiable risk factors. METHODS: AM concentrations were measured in 290 BRCA1/2 mutation carriers without overt CVD, participating in the randomized controlled LIBRE study (NCT numbers: NCT02087592, NCT02516540), by an immunoassay (sphingotest® bio-ADM®). Subjects were classified into high versus low AM levels based on the median plasma AM level in the entire cohort (13.9 pg/mL). Univariate logistic regression models were used to estimate the odds ratio (OR) of having high circulating AM levels by metabolic syndrome (MetS), cardiorespiratory fitness (CRF), body mass index (BMI), circulating insulin, smoking, current age, BRCA mutation status (BRCA1 or BRCA2) and previous diagnosis of breast cancer. MetS was defined in accordance with the criteria of the Third Adult Treatment Panel (ATP III). CRF was measured by peak oxygen uptake (VO2peak) assessed on a cycle ergometer via standardized cardiopulmonary exercise testing. RESULTS: Of all women (median age: 43 years), 57.9% had a previous diagnosis of breast cancer. The median time between diagnosis and study entry was 3 years (range: 0-32 years). Women fulfilling the criteria of metabolic syndrome had over 17 times higher odds of having increased AM levels compared to those who did not meet the criteria (OR = 17.49, p &amp;lt; 0.001). Moreover, high AM levels were associated with lower VO2peak (OR = 0.91, p &amp;lt; 0.001), higher BMI (OR = 1.24, p &amp;lt; 0.001) and higher circulating insulin levels (OR = 1.1, p &amp;lt; 0.001). AM levels were higher in women who have ever smoked (OR = 1.73, p = 0.022), and AM levels increased with the number of pack-years smoked (OR = 1.03, p = 0.06). AM levels were not associated with age (p = 0.143), BRCA mutation status (p = 0.51) or previous diagnosis of breast cancer (p = 0.48). After adjustment for confounding variables, we observed that MetS (OR = 10.78, p = 0.002) and VO2peak (OR = 0.92, p = 0.001) were independent determinants of circulating AM. CONCLUSIONS: This is the first study in BRCA mutation carriers that has linked circulating AM levels to MetS and CRF. The long-term clinical implications of these findings are yet to be determined. Conflict of interest: The study is funded by the German Cancer Aid (Deutsche Krebshilfe) within the Priority Program “Primary Prevention of Cancer” (Grant no. 110013). JS and OH are employed by Sphingotec GmbH, a company having patent rights in and commercializing the bio-ADM assay. SG and MK received grants from Sphingotec GmbH. JL, MYD, MB and MH have nothing to disclose. Citation Format: Jacqueline Lammert, Sabine Grill, Maryam Yahiaoui-Doktor, Maryam Basrai, Joachim Struck, Oliver Hartmann, Martin Halle, Marion Kiechle. High circulating levels of adrenomedullin are associated with metabolic syndrome and low cardiorespiratory fitness in BRCA1 and BRCA2 mutation carriers [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-10-16.

&lt;p&gt;Safety, Tolerability, and Pharmacokinetics of Adrenomedullin in Healthy Males: A Randomized, Double-Blind, Phase 1 Clinical Trial&lt;/p&gt;

BackgroundAdrenomedullin (AM), an endogenous vasodilative peptide, has immunomodulative effects and acts as an accelerator of mucosal regeneration in the digestive tract. AM has shown beneficial effects in rodent models of inflammatory bowel disease and patients with ulcerative colitis. The present study aimed to evaluate the pharmacodynamic properties and safety of AM in healthy male adults in a phase 1 clinical trial.MethodsThis phase 1, randomized, double-blind, single-center study was conducted on healthy males aged 20–65 years. Subjects received either a placebo, 3 ng/kg/min AM, 9 ng/kg/min AM, or 15 ng/kg/min AM via continuous 12-h intravenous infusion. Other subjects received either placebo or 15 ng/kg/min AM for 8 h per day for 7 days. Adverse events (AEs), vital signs, physical examinations, laboratory tests, electrocardiograms (ECG), and pharmacokinetics were assessed.FindingsAll 24 subjects in the single-dose test completed the study. Of the 12 subjects in multiple dosing test, one from the AM group withdrew owing to a headache. No serious AEs were reported. Hemodynamic parameters were well maintained in all subjects. Slight ECG abnormalities were observed in the single-dose test. The plasma concentration of AM progressively increased in a dose-dependent manner and reached Cmax at the end of administration. Plasma AM rapidly returned to baseline concentrations after termination, with a T1/2 of under 60 min.InterpretationThis is the first phase 1 trial in healthy men evaluating the safety of AM. Our results demonstrate the safety and tolerability of AM for subsequent Phase 2 trials.

Polyethylene glycol-conjugated human adrenomedullin as a possible treatment for vascular dementia

Adrenomedullin (AM) is a multifunctional bioactive peptide. Recent studies have shown that AM has protective effects against ischemic brain damage. We recently prepared a long-acting human AM derivative that was conjugated with a 60 kDa polyethylene glycol (PEG-AM), which had an effect similar to that of native AM. In this study, we examined the effect of PEG-AM on four-vessel occlusion model rats, which exhibit vascular dementia. From day 10 to day 14 after surgery, the learning and memory abilities of the rats were examined using a Morris water maze. The rats were treated with a single subcutaneous injection of 1.0 or 10.0 nmol/kg of PEG-AM. PEG-AM treatment reduced the escape latency in the hidden platform test. Furthermore, the treatment increased the time spent in the platform quadrant in the probe test. The data showed that PEG-AM injection prevented memory loss and learning disorders in dose-dependent manner. On day 14, the immunoreactive AM concentration in plasma was 9.749 ± 2.167 pM in the high-dose group (10.0 nmol/kg) and 0.334 ± 0.073 pM in the low-dose group (1.0 nmol/kg). However, even in the low-dose group, a significant effect was observed in both tests.The present data indicate that PEG-AM is a possible therapeutic agent for the treatment of ischemic brain injury or vascular dementia.

Adrenomedullin alleviates the pyroptosis of Leydig cells by promoting autophagy via the ROS\u2013AMPK\u2013mTOR axis

Adrenomedullin (ADM) exerts anti-oxidant, anti-inflammatory and anti-apoptotic effects in Leydig cells. However, the role and mechanism of ADM in the pyroptosis of Leydig cells are poorly understood. This study first showed the protective effects of ADM on the pyroptosis and biological functions of Leydig cells exposed to lipopolysaccharide (LPS) by promoting autophagy. Primary rat Leydig cells were treated with various concentrations of LPS and ADM, together with or without N-acetyl-L-cysteine (NAC) or 3-methyladenine (3-MA). Cell proliferation was detected through CCK-8 and BrdU incorporation assays, and ROS level was measured with the DCFDA assay. Real-time PCR, western blot, immunofluorescence, transmission electron microscopy, TUNEL and flow cytometry were performed to examine ADM’s effect on the pyroptosis, autophagy and steroidogenic enzymes of Leydig cells and AMPK/mTOR signalling. Like NAC, ADM dose-dependently reduced LPS-induced cytotoxicity and ROS overproduction. ADM also dose-dependently ameliorated LPS-induced pyroptosis by reversing the increased expression of NLRP3, ASC, caspase-1, IL-1β, IL-18, GSDMD, caspase-3, caspase-7, TUNEL-positive and PI and active caspase-1 double-stained positive rate, DNA fragmentation and LDH concentration, which could be rescued via co-incubation with 3-MA. ADM dose-dependently increased autophagy in LPS-induced Leydig cells, as confirmed by the increased expression of LC3-I/II, Beclin-1 and ATG-5; decreased expression of p62 and autophagosomes formation; and increased LC3-II/LC3-I ratio. However, co-treatment with 3-MA evidently decreased autophagy. Furthermore, ADM dose-dependently rescued the expression of steroidogenic enzymes, including StAR, P450scc, 3β-HSD and CYP17, and testosterone production in LPS-induced Leydig cells. Like rapamycin, ADM dose-dependently enhanced AMPK phosphorylation but reduced mTOR phosphorylation in LPS-induced Leydig cells, which could be rescued via co-incubation with 3-MA. In addition, pyroptosis was further decreased, and autophagy was further promoted in LPS-induced Leydig cells upon co-treatment with ADM and rapamycin. ADM may protect the steroidogenic functions of Leydig cells against pyroptosis by activating autophagy via the ROS–AMPK–mTOR axis.

A double-blind, placebo-controlled, randomised, multicentre, proof-of-concept and dose-finding phase II clinical trial to investigate the safety, tolerability and efficacy of adrecizumab in patients with septic shock and elevated adrenomedullin concentration (AdrenOSS-2)

IntroductionSepsis remains a major health problem with an increasing incidence, high morbidity and high mortality. Apart from treatment with antibiotics and organ support, no approved specific adjunct therapies currently exist....

Adrenomedullin in heart failure: pathophysiology and therapeutic application.

Adrenomedullin (ADM) is a peptide hormone first discovered in 1993 in pheochromocytoma. It is synthesized by endothelial and vascular smooth muscle cells and diffuses freely between blood and interstitium. Excretion of ADM is stimulated by volume overload to maintain endothelial barrier function. Disruption of the ADM system therefore results in vascular leakage and systemic and pulmonary oedema. In addition, ADM inhibits the renin–angiotensin–aldosterone system. ADM is strongly elevated in patients with sepsis and in patients with acute heart failure. Since hallmarks of both conditions are vascular leakage and tissue oedema, we hypothesize that ADM plays a compensatory role and may exert protective properties against fluid overload and tissue congestion. Recently, a new immunoassay that specifically measures the biologically active ADM (bio‐ADM) has been developed, and might become a biomarker for tissue congestion. As a consequence, measurement of bio‐ADM might potentially be used to guide diuretic therapy in patients with heart failure. In addition, ADM might be used to guide treatment of (pulmonary) oedema or even become a target for therapy. Adrecizumab is a humanized, monoclonal, non‐neutralizing ADM‐binding antibody with a half‐life of 15 days. Adrecizumab binds at the N‐terminal epitope of ADM, leaving the C‐terminal side intact to bind to its receptor. Due to its high molecular weight, the antibody adrecizumab cannot cross the endothelial barrier and consequently remains in the circulation. The observation that adrecizumab increases plasma concentrations of ADM indicates that ADM‐binding by adrecizumab is able to drain ADM from the interstitium into the circulation. We therefore hypothesize that administration of adrecizumab improves vascular integrity, leading to improvement of tissue congestion and thereby may improve clinical outcomes in patients with acute decompensated heart failure. A phase II study with adrecizumab in patients with sepsis is ongoing and a phase II study on the effects of adrecizumab in patients with acute decompensated heart failure with elevated ADM is currently in preparation.

Circulating Adrenomedullin Is Elevated in Gestational Diabetes and Its Role in Impaired Insulin Production by β-Cells.

Defective pancreatic β-cell adaptation in pregnancy plays an important role in the pathophysiology of gestational diabetes mellitus (GDM), but the molecular basis remains unclear. Objectives of this study were to determine if circulating levels of adrenomedullin (ADM) in women with GDM are elevated and to assess the effects of ADM on insulin synthesis and secretion by human pancreatic β-cells. A stable gene product of ADM precursor, midregional pro-adrenomedullin(MR-proADM), was measured in plasma of pregnant women with normal glucose tolerance (NGT, n = 10) or GDM (n = 11). The β-Lox5 cell line, derived from human pancreatic β-cells, was transduced with homeodomain transcription factor pancreatic-duodenal homeobox (PDX) factor 1 (PDX1) encoding lentiviral vector and treated with different doses of ADM. mRNA for insulin, ADM, and its receptor components in β-Lox5 cells and insulin in media were measured. Plasma MR-proADM levels were significantly higher in GDM compared with patients with NGT. Pancreatic β-Lox5 cells express mRNA for insulin, ADM, and its receptor components. PDX1 transduction and cell-cell contact synergistically promote β-Lox5 cells insulin mRNA and secretion. Furthermore, ADM dose-dependently inhibited mRNA and secretion of insulin in β-Lox5 cell aggregates. These inhibitory effects were blocked by ADM antagonist ADM22-52, cAMP-dependent protein kinase A inhibitor KT5720, and Erk inhibitor PD98059, but not by PI-3K the inhibitor wortmannin. Circulating ADM concentrations were elevated in pregnant women with GDM. ADM suppresses insulin synthesis and secretion by pancreatic β-cells in vitro. Thus, increased circulating ADM may contribute to the defective adaptation of β-cells in diabetic pregnancies, and blockade of ADM actions with its antagonists may improve β-cell functions.

ADRENOMEDULIN DI KARSINOMA PAYUDARA DENGAN METASTASIS

Metastasis is the leading cause of mortality in patients with breast cancer. The molecular biology behind the metastasis is verycomplex and may require changes in the regulation of the cell cycle, protein that promotes autocrine growth loop, and the protein thatcauses epithelial to mesenchymal transition. More complex, it is clear that the biology of metastasis is partly governed by the non-tumourcells, including fibroblasts, endothelial cells and myoepithelial cells. Adrenomedullin is an autocrine growth factor produced by the renalcarcinoma cells. However, previous studies indicated that adrenomedullin can be secreted in various carcinoma tissue and carcinoma cells.Adrenomedullin may mediate immunosuppression, antiapoptosis, angiogenesis and proliferation, thus it is an important tumour cellsurvival factor underlying human carcinoma genesis. The role of adrenomedullin in the carcinoma genesis, invasion and metastasis hasbeen greatly focused. The aim of this study was to determine the concentration of adrenomedullin in patients with metastatic breast cancer.A total of 64 patients with breast cancer aged 21–90 years (63 women and 1 man) in Jakarta has been participated in this study aftersigning informed consent. Metastasis was confirmed by examination of bone scanning. Concentrations of adrenomedullin were measuredby EnzymeLinked Immunosorbent Assay (ELISA) using a commercial kit. Based on examination of bone scanning, there were 24 (37.5%)subjects with metastasis and 40 (62.5%) nonmetastasis. Mean of the concentrations of adrenomedullin in the subjects with metastasiswas 252.5 (205.0–299.9) pg/mL, while in the nonmetastasis was 203.1 (178.7–227.5) pg/mL. The concentrations of adrenomedullinwere significantly higher in subjects with metastasis than nonmetastasis (p=0.041). High concentration of adrenomedullin in the subjectswith metastasis suggests that adrenomedullin may be more likely to be involved in metastasis.

Human Milk Adrenomedullin Is Unstable During Cold Storage at 4°C

Under some circumstances human milk (HM) extraction and refrigerated storage may be necessary. Depending on the length and on the type of cold storage, milk may lose some important properties, but current advices on safe HM storage are discordant. Moreover until now no data in literature were present on the effect of prolonged cold storage on biologically active components of the HM such as adrenomedullin (AM). This important peptide is involved in response to hypoxia and inflammation, associated with neovascularization, in several tissues. The aim is to evaluate: (a) the presence of AM in preterm and term HM and (b) the concentration of AM in refrigerated milk at 4°C at 24-hour intervals, up to 96 hours of storage. The experiment was repeated four times. Immediately after collection, each HM sample deriving from each mother was divided into two parts as follows: "Pool" line and "Single Mother" line. One part (Pool line) was pooled and then divided into five aliquots. The other part (Single Mother line) was divided into five aliquots. From each line, one aliquot was analyzed within 3 hours, while the others were stored in the refrigerator for 24, 48, 72, and 96 hours, respectively, and then analyzed. AM levels were determined using a specific ELISA test. AM was detectable in all samples. Its concentration was significantly higher in preterm milk with respect to term milk (p < 0.05). Significant differences were observed during the cold storage: the AM levels decreased steadily during the storage and the remaining concentration at 96 hours is ∼2%. This study provides evidences regarding the presence of AM in HM, regardless of the gestational age. In particular, the refrigeration of fresh HM in controlled conditions significantly affected its bioactivity and nutritional quality related with AM, already at 24 hours.