Effects of liraglutide on cardiovascular risk biomarkers in patients with type 2 diabetes and albuminuria: A sub-analysis of a randomized, placebo-controlled, double-blind, crossover trial.

We assessed the effects of liraglutide treatment on five cardiovascular risk biomarkers, reflecting different pathophysiology: tumour necrosis factor (TNF)-α; soluble urokinase plasminogen activator receptor (suPAR); mid-regional pro-adrenomedullin (MR-proADM); mid-regional pro-atrial natriuretic peptide (MR-proANP); and copeptin, in people with type 2 diabetes with albuminuria. In a randomized, double-blind, placebo-controlled, crossover trial we enrolled people with type 2 diabetes and persistent albuminuria (urinary albumin-to-creatinine ratio [UACR] >30 mg/g) and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2 . Participants received liraglutide (1.8 mg/d) and matched placebo for 12 weeks, in random order. The primary endpoint was change in albuminuria; this was a prespecified sub-study. A total of 32 participants were randomized, of whom 27 completed the study. TNF-α level was 12% (95% confidence interval [CI] 3; 20) lower after liraglutide treatment compared with placebo (P = .012); MR-proADM level was 4% (95% CI 0; 8) lower after liraglutide treatment compared with placebo (P = .038), and MR-proANP level was 13% (95% CI 4; 21) lower after liraglutide treatment compared with placebo (P = .006). In the present study, we showed anti-inflammatory effects of liraglutide treatment, reflected in reductions in levels of TNF-α and MR-proADM, while the reduction in MR-proANP levels may represent a clinically relevant benefit with regard to heart failure.

Bone-Conditioned Medium Changes Gene Expression in Bone-Derived Fibroblasts.

PURPOSE: Autologous bone is used for augmentation in the course of oral implant placement. Bone grafts release paracrine signals that can modulate mesenchymal cell differentiation in vitro. The detailed genetic response of the bone-derived fibroblasts to these paracrine signals has remained elusive. Paracrine signals accumulate in bone-conditioned medium (BCM) prepared from porcine cortical bone chips. MATERIALS AND METHODS: In this study, bone-derived fibroblasts were exposed to BCM followed by a whole genome expression profiling and downstream quantitative reverse transciptase polymerase chain reaction of the most strongly regulated genes. RESULTS: The data show that ADM, IL11, IL33, NOX4, PRG4, and PTX3 were differentially expressed in response to BCM in bone-derived fibroblasts. The transforming growth factor beta (TGF-ß) receptor 1 antagonist SB431542 blocked the effect of BCM on the expression of the gene panel, except for IL33. CONCLUSION: These in vitro results extend existing evidence that cortical bone chips release paracrine signals that provoke a robust genetic response in mesenchymal cells that is not exclusively mediated via the TGF-ß receptor. The present data provide further insights into the process of graft consolidation.

Pathophysiological functions of adrenomedullin and natriuretic peptides in patients with primary aldosteronism.

To measure the plasma concentrations of adrenomedullin (ADM),atrial natriuretic peptide (ANP), and brain natriuretic peptide (BNP), and investigate their pathophysiological functions in patients with primary aldosteronism (PA). Between June 2006 and December 2012, we recruited 25 patients with untreated PA, 30 patients with untreated low-renin essential hypertension (EH), and 35 healthy control subjects. The plasma concentrations of ADM, ANP, and BNP were measured in all the subjects. After 4 weeks of effective antihypertensive therapy with slow-release nifedipine, the three peptides were measured again in the PA and low-renin EH subjects. Unilateral laparoscopic adrenalectomy was performed in all the PA patients; 2 weeks after surgery, the three peptides were measured again. The PA patients had significantly higher plasma concentrations of ADM, ANP, and BNP than the low-renin EH and control subjects. The low-renin EH and control subjects significantly differed in the concentrations of the three peptides between low-renin EH and control subjects. ADM was the most important peptide associated with aldosterone or blood pressure in the PA patients. Plasma ADM concentration was not only correlated with plasma aldosterone concentrations, but also with systolic and diastolic blood pressures, and plasma ANP and BNP concentrations in the PA patients. By contrast, ADM concentration was not related to blood urea nitrogen levels, serum creatinine levels, and glomerular filtration rates. After antihypertensive treatment, the concentrations of the three peptides significantly decreased in the low-renin EH patients, but remained unchanged in the PA subjects. However, these concentrations significantly decreased 2 weeks after laparoscopic adrenalectomy in the PA subjects. ADM, ANP, and BNP possibly participate in the mechanisms counteracting further elevation of blood pressure or plasma volume expansion resulting from aldosterone hypersecretion in PA patients. An ADM/aldosterone local regulatory mechanism may be involved in regulating adrenal adenoma functions.

Adrenomedullin is up-regulated in patients with pancreatic cancer and causes insulin resistance in ß cells and mice.

BACKGROUND & AIMS: New-onset diabetes in patients with pancreatic cancer is likely to be a paraneoplastic phenomenon caused by tumor-secreted products. We aimed to identify the diabetogenic secretory product(s) of pancreatic cancer. METHODS: Using microarray analysis, we identified adrenomedullin as a potential mediator of diabetes in patients with pancreatic cancer. Adrenomedullin was up-regulated in pancreatic cancer cell lines, in which supernatants reduced insulin signaling in beta cell lines. We performed quantitative reverse-transcriptase polymerase chain reaction and immunohistochemistry on human pancreatic cancer and healthy pancreatic tissues (controls) to determine expression of adrenomedullin messenger RNA and protein, respectively. We studied the effects of adrenomedullin on insulin secretion by beta cell lines and whole islets from mice and on glucose tolerance in pancreatic xenografts in mice. We measured plasma levels of adrenomedullin in patients with pancreatic cancer, patients with type 2 diabetes mellitus, and individuals with normal fasting glucose levels (controls). RESULTS: Levels of adrenomedullin messenger RNA and protein were increased in human pancreatic cancer samples compared with controls. Adrenomedullin and conditioned media from pancreatic cell lines inhibited glucose-stimulated insulin secretion from beta cell lines and islets isolated from mice; the effects of conditioned media from pancreatic cancer cells were reduced by small hairpin RNA-mediated knockdown of adrenomedullin. Conversely, overexpression of adrenomedullin in mice with pancreatic cancer led to glucose intolerance. Mean plasma levels of adrenomedullin (femtomoles per liter) were higher in patients with pancreatic cancer compared with patients with diabetes or controls. Levels of adrenomedullin were higher in patients with pancreatic cancer who developed diabetes compared those who did not. CONCLUSIONS: Adrenomedullin is up-regulated in patients with pancreatic cancer and causes insulin resistance in ß cells and mice.

Basic fibroblast growth factor upregulates adrenomedullin expression in ovarian epithelial carcinoma cells via JNK-AP-1 pathway.

Adrenomedullin (AM), a potent vasodilator peptide, present in various kinds of tumors. Basic fibroblast growth factor (bFGF) has broad biological functions involving in the regulation of cell growth, differentiation and proliferation. Here we investigated whether AM expression could be induced by bFGF in human ovarian epithelial carcinoma cells and explored the mediating mechanism. The expression of AM was examined by real time PCR and Western blotting. Transcriptional control was analyzed by transient transfection assay, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay. AM expression was detected in ovarian epithelial carcinoma both in mRNA and protein levels in vivo. AM mRNA expression in CAOV(3) was induced by bFGF in a time- and dose-dependent manner, which could be attenuated by bFGF neutralizing antibody. JNK was activated by bFGF stimulation. The bFGF induced increase in AM expression was significantly attenuated by SP600125, a specific JNK inhibitor. EMSA study, ChIP assay and promoter activity analysis showed that AM expression induced by bFGF requires the AP-1 motif on the AM promoter, which is located at -1174 and -922 bp upstream of the transcription start site. The present study demonstrated that AM is expressed in ovarian epithelial carcinoma tissue and bFGF can induce the expression of AM through the JNK-AP-1 pathway in ovarian epithelial carcinoma cell line CAOV(3).

Small-molecule negative modulators of adrenomedullin: design, synthesis, and 3D-QSAR study.

Adrenomedullin (AM) is a peptidic hormone that was isolated in 1993, the function of which is related to several diseases such as diabetes, hypertension, and cancer. Compound 1 is one of the first nonpeptidic small-molecule negative modulators of AM, identified in a high-throughput screen carried out at the National Cancer Institute. Herein we report the synthesis of a series of analogues of 1. The ability of the synthesized compounds to disrupt the binding between AM and its monoclonal antibody has been measured, together with surface plasmon resonance (SPR)-based binding assays as implemented with Biacore technology. These data were used to derive a three-dimensional quantitative structure-activity relationship (3D-QSAR) model, with a q(2) (LOO) value of 0.8240. This study has allowed us to identify relevant features for effective binding to AM: the presence of a hydrogen-bond donor group and an aromatic ring. Evaluation of the ability of selected compounds to modify cAMP production in Rat2 cells showed that the presence of a free carboxylic acid is essential for negative AM modulation.

Icariside II from Epimedium koreanum inhibits hypoxia-inducible factor-1alpha in human osteosarcoma cells.

Hypoxia-inducible factor-1 (HIF-1) is an important tumor-selective therapeutic target for solid tumors. Icariside II was isolated from Epimedium koreanum through successive fractionation with ethyl acetate, n-butanol, chloroform and hexane, followed by gel column chromatography. Icariside II attenuated the protein level of HIF-1alpha induced by hypoxia in human osteosarcoma (HOS) cells in a concentration-dependent manner, probably by enhancing the interaction rate between von Hippel-Lindau (VHL) and HIF-1alpha. Furthermore, Icariside II down-regulated the levels of HIF-inducible genes involved in angiogenesis, metastasis, and glucose metabolism, such as vascular endothelial growth factor (VEGF), urokinase plasminogen activator receptor (uPAR), adrenomedullin (ADM), matrix metalloproteinase 2 (MMP2), aldolase A, and enolase 1 in HOS cells. Icariside II also inhibited the migration rate in HOS cells and tube formation rate in human umbilical vein endothelium cells (HUVECs). Overall, these results suggest the potential use of Icariside II as a therapeutic candidate against various diseases that involve overexpression of HIF-1alpha.

The effects of anticancer drugs on levels of nitric oxide and adrenomedullin.

Nephrotoxicity is one of the most important complications of anticancer treatment. Ifosfamide, platinum and methotrexate (MTX) affect renal tubular epithelial cells. Nitric oxide (NO) serves many functions within the kidney. Adrenomedullin (AM) is a potent vasodilator peptide, and may function as a circulating hormone and an autocrine/paracrine mediator involved in the regulation of the cardiovascular system, blood pressure, and renal function. It also has a renoprotective effect and inhibits the generation of reactive oxygen metabolites. To our knowledge, no studies have investigated the effects of anticancer drugs on levels of AM and NO. We investigated the effects of these drugs on the levels of AM and total nitrite, a stable product of NO, and their relations to renal functions. The study was performed in 18 patients (13 males, 5 females) who received chemotherapeutic regimens including high-dose MTX or ifosfamide and platinum. Total nitrite was quantitated by means of the Griess reaction, while AM level was measured by high performance liquid chromatography (HPLC). Plasma total nitrite level (micromol/L) was decreased after chemotherapy (78.73 +/- 47.28 vs. 46.69 +/- 13.89, p: 0.002). A statistically significant difference was found between fractional excretion (FE) of total nitric oxide (FE(NO)) before and after chemotherapy (25.89 +/- 23.11 vs. 51.74 +/- 40.01, p: 0.008). The differences in plasma AM levels (pmol/ml) before (25.07 +/- 4.98) and after (30.20 +/- 1.39) chemotherapy were also statistically significant (p: 0.005). FE(AM) after chemotherapy (1.41 +/- 1.01) was found to be higher than before chemotherapy (0.64 +/- 0.43) (p: 0.000). Our results indicate that some chemotherapeutic agents (high-dose MTX, ifosfamide, and cisplatinium) may cause renal tubular damage. FE(AM) and FE(NO) may also be used for the detection of subclinical acute tubular nephrotoxicity. However, further detailed researches will be necessary to establish the certain role of NO and AM in toxicities of chemotherapeutic agents.

Effect of adrenergic blockade on plasma adrenomedullin concentration during static handgrip in patients with heart failure.

Our previous study showed that static handgrip caused increases in the plasma adrenomedullin (ADM) both in patients with heart failure (HF) and healthy subjects. The present study was designed to determine the role of the sympathetic nervous system in mediating plasma ADM changes during handgrip in patients with HF. Twelve male HF patients (II class NYHA) treated with carvedilol, a non-selective adrenergic blocker (TC) and 12 patients untreated with carvedilol (UC) performed two 3-min bouts of static handgrip at 30% of maximal voluntary contraction, alternately with each hand. At the end of both exercise bouts and in 5 min of the recovery period, plasma ADM and catecholamines were determined. In addition, heart rate, blood pressure and stroke volume (SV) were measured. The baseline plasma ADM, noradrenaline (NA) and adrenaline (A) levels were similar in the two groups of patients, while SV was higher (P<0.05) in TC than in UC. During exercise plasma ADM concentrations were lower (P<0.05) in TC than in UC, but the handgrip-induced increases in plasma ADM did not differ between the groups. Plasma ADM correlated with NA concentrations (r = 0.764) and with SV (r = -0.435) and increases in plasma ADM expressed as percentage of baseline values correlated with those of plasma NA (r = 0.499), diastolic BP (r = 0.550) and total peripheral resistance (r = 0.435). The study suggests that the sympathetic nervous system may be involved in the stimulation of ADM secretion during static exercise either directly or by changes in the haemodynamic response.