Adrenomedullin Gene Research Articles

The Role of Kidney Intercalated Cells in the Immune Response Against UTIs

Introduction: Urinary tract infections (UTIs) are among the most prevalent infections. About 3 in 5 women will experience UTIs in their lifetime, resulting from a bacterial infection caused by uropathogenic E. coli (UPEC). Ascending UPEC first adhere to the collecting ducts, where intercalated cells (ICs) are essential for raising an innate immune response activated by UPEC-outer membrane lipopolysaccharide (LPS). Interestingly, individuals with distal renal tubular acidosis (dRTA) who have a mutation on the gene encoding the kidney anion exchanger 1 (kAE1) have a decreased abundance of IC and are at a higher risk for UTIs. The cellular mechanisms contributing to this higher vulnerability to UTIs remain unclear. Objective and Hypothesis: To enhance our understanding of the immune response mechanisms of collecting duct cells in dRTA patients during UTIs, we hypothesize that the loss of intercalated cells (ICs) in dRTA results in an inadequate immune response against UPEC. Methods: Mouse inner medullary collecting duct cells (mIMCD3) and a mouse strain with a knock-in mutation for kAE1 dRTA (specifically, R607H, equivalent to human R589H) were utilized in the study. We identified and quantified innate immunity markers in mIMCD3 cells exposed to vehicle, UPEC or LPS using qRT-PCR and immunoblot. Primary IC were prepared by magnetic-activated cell sorting (MACS). Various incubation conditions, including exposure to vehicle, LPS, control K12 bacteria, and UPEC for different time intervals were assessed to determine the best experimental conditions. Transurethral UPEC inoculation procedures were also performed to validate results obtained in the in vitro approaches. Results: Experiments on mIMCD3 cells showed a significant increase in the innate immunity marker adrenomedullin (ADM) following exposure to UPEC or LPS, compared to the control group. After 17 h, exposing the primary MACS-enriched ICs to UPEC significantly increased the adrenomedullin protein abundance. UPEC transurethral infections in dRTA mice resulted in a higher bacterial load and increased IL-1β, IL-6, and TNF-α mRNA and protein levels compared to WT mice at 24 post-UTI. In the transgenic mice, ADM gene expression was not up-regulated to the same extent as in WT mice, but LCN2/NGAL gene expression was significantly higher. Conclusions: Our study suggests that the loss of IC in a dRTA mouse model results in higher inflammation and reduced immunity against UPEC exposure. Our research will unravel new therapeutic leads on the intracellular signaling pathway(s) and cellular changes that result in IC-mediated renal protection. The findings may contribute to the development of novel therapeutics for UTIs. Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Institutes of Health Research (CIHR), University of Alberta Graduate Recruitment Scholarship (2023). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

382 Precision and Individualized Medicine: Quantification of Brain Cancer Cell Invasion in Confined Microfluidic Spaces Predicts Prognosis

INTRODUCTION: Clinical prognosis of patients with glioblastoma (GBM) is calculated with clinical scores, extent of resection, molecular markers, and tumor subtypes. However, these are often hampered by patient comorbidities, drug toxicity, and other confounding factors. We designed a confined 3D microfluidic technology based on the brain cytoarchitecture by mimicking the diameters of the perivascular spaces and white matter tracts utilized by GBM to invade. METHODS: Patient-derived GBM cell lines (n = 13) were obtained from patients undergoing surgery. After cell culture, the GBM cells’ abilities to migrate and proliferate with MAqCI were evaluated. MAqCI score was calculated via logistic regression. Patients were categorized into low- and high-PFS. Predicted scores were correlated with the clinical status of patients. Cells were treated with gold standard and experimental drugs, and scores were calculated to predict response to treatment. RESULTS: MAqCI Predicted PFS with 83% accuracy, 84.6% sensitivity, and 75% specificity and allowed for the classification of short- and long-PFS (*p = 0.035). Survival based on MAqCI scores separated by short-term (n = 5) and long-term (n = 8) PFS, showed a significant difference between groups (**p = 0.002). After treatment with gold-standard therapy, responder patients were identified based on changes in the MAqCI score. RNAseq of highly motile cells isolated from MAqCI allowed for the identification of druggable targets. An FDA-approved antidepressant against the adrenomedullin gene was selected for MAqCI testing. Changes in MAqCI score after treatment allowed for the identification of responder patients. CONCLUSIONS: Cell invasion properties are directly correlated with patient prognosis. MAqCI could be utilized clinically as a companion assay for predicting tumor recurrence and selecting drugs for individualized GBM treatment.

Anti-apoptotic effect of adrenomedullin gene delivery on Leydig cells by suppressing TGF-β1 via the Hippo signaling pathway

This study aims to establish whether adrenomedullin (ADM) is capable to restore the steroidogenic functions of Leydig cells by suppressing transforming growth factor-β1 (TGF-β1) through Hippo signaling. Primary Leydig cells were treated with lipopolysaccharide (LPS), an adeno-associated virus vector that expressed ADM (Ad-ADM) or sh-RNA of TGF-β1 (Ad-sh-TGF-β1). The cell viability and medium concentrations of testosterone were detected. Gene expression and protein levels were determined for steroidogenic enzymes, TGF-β1, RhoA, YAP, TAZ and TEAD1. The role of Ad-ADM in the regulation of TGF-β1 promoter was confirmed by ChIP and Co-IP. Similar to Ad-sh-TGF-β1, Ad-ADM mitigated the decline in the number of Leydig cells and plasma concentrations of testosterone by restoring the gene and protein levels of SF-1, LRH1, NUR77, StAR, P450scc, 3β-HSD, CYP17 and 17β-HSD. Similar to Ad-sh-TGF-β1, Ad-ADM not only inhibited the LPS-induced cytotoxicity and cell apoptosis but also restored the gene and protein levels of SF-1, LRH1, NUR77, StAR, P450scc, 3β-HSD, CYP17 and 17β-HSD, along with the medium concentrations of testosterone in LPS-induced Leydig cells. Like Ad-sh-TGF-β1, Ad-ADM improved LPS-induced TGF-β1 expression. In addition, Ad-ADM suppressed RhoA activation, enhanced the phosphorylation of YAP and TAZ, reduced the expression of TEAD1 which interacted with HDAC5 and then bound to TGF-β1 gene promoter in LPS-exposed Leydig cells. It is thus suspected that ADM can exert anti-apoptotic effect to restore the steroidogenic functions of Leydig cells by suppressing TGF-β1 through Hippo signaling.

The neuropeptide Adrenomedullin Promoted the Progression of Head and Neck Squamous Carcinoma by Negatively Regulating Tumour Immunity

Objective: To investigate the putative regulatory mechanisms and functions of the neuropeptide gene adrenomedullin (ADM) in head and neck squamous cell carcinoma (HNSC). Methods: Publicly available data from the TCGA-HNSC database were utilized to explore the involvement of ADM single gene in HNSC by analyzing RNA expression levels of ADM. The involvement of ADM in tumor immunity was particularly investigated from the aspect of tumor-infiltrating immune cells, immune modulator genes, immune checkpoint genes, Estimate-Immune-Stromal score, and immune clusters’ prognostic values. Statistical analysis of the data pertaining to cancer and non-cancerous samples was performed using R software packages. Many web servers were used in the present analyses, including cBioportal, TIMER, STRING, GeneMANIA, and GEPIA. Results: ADM was found to be significantly upregulated in HNSC tumor samples and associated with worse prognostic outcomes. ADM-significantly correlated genes in HNSC were enriched in several tumor promoting pathways, including cytokine-cytokine receptor interaction, HIF-1 signaling, MAPK signaling, chemokine signaling, AGE-RAGE signaling, Relaxin signaling, viral protein interaction with cytokine and cytokine receptor, and NF-kappa B signaling. ADM is involved in tumor immunity of HNSC by being negatively correlated with several tumor-infiltrating immune cells, including tumor macrophages, T cells, B cells, Treg cells, T helper cells, Th17 cells, NK cells, mast cells, and dendritic cells. The negative correlation was observed between ADM expression and the majority of immunomodulator genes. ADM was also found to be negatively correlated with the Estimate-Stromal-Immune score in HNSC, indicating its involvement in the tumor immune microenvironment. Conclusions: ADM gene may play a significant role in promoting the progression of HNSC by negatively regulating immune cells, mediating cytokine and chemokine signaling, HIF-1 signaling, MAPK signaling, and NF-kappa B signaling. Therefore ADM can be regarded as a valuable candidate biomarker and holds promising prospects in treating head and neck cancer.

Local adrenomedullin gene delivery inhibits Leydig cell dysfunction by rescuing steroidogenic enzymes in vivo.

Adrenomedullin (ADM) has beneficial effects on Leydig cells under pathological conditions, including lipopolysaccharide (LPS)-induced orchitis. Our previous studies demonstrated that ADM exerts a restorative effect on steroidogenesis in LPS-treated primary rat Leydig cells by attenuating oxidative stress, inflammation and apoptosis. In this study, we aim to investigate whether ADM inhibits Leydig cell dysfunction by rescuing steroidogenic enzymes in vivo. Rats were administered with LPS and injected with Ad-ADM, an adeno-associated virus vector that expressed ADM. Then, rat testes were collected for 3β-hydroxysteroid dehydrogenase (3β-HSD) immunofluorescence staining. Steroidogenic enzymes or steroidogenic regulatory factors or protein, including steroidogenic factor-1 (SF-1), liver receptor homologue-1 (LRH1), Nur77, steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side chain cleavage enzyme (P450scc), 3β-HSD, cytochrome P450 17α-hydroxylase/17, 20 lyase (CYP17) and 17β-hydroxysteroid dehydrogenase (17β-HSD), were detected via gene expression profiling and western blot analysis. Plasma testosterone concentrations were measured. Results showed that ADM may inhibit Leydig cell dysfunction by rescuing steroidogenic enzymes and steroidogenic regulatory factors in vivo. The reduction in the number of Leydig cells after LPS exposure was reversed by ADM. ADM rescued the gene or protein levels of SF-1, LRH1, Nur77, StAR, P450scc, 3β-HSD, CYP17 and 17β-HSD and plasma testosterone concentrations. To summarize ADM could rescue some important steroidogenic enzymes, steroidogenic regulatory factors and testosterone production in Leydig cells in vivo.

Effects of Adrenomedullin (ADM)-Modified Bone Marrow Mesenchymal Stem Cells (BMSCs) Transplantation on Cardiac Function and Matrix Metalloproteinase Levels in Rats with Heart Failure

After ADM gene treatment, bone marrow mesenchymal stem cells (BMSCs) were transplanted into rats with heart failure to study its effect on rat heart function and matrix metalloproteinases (MMPs) expression. The rats were assigned into control group, BMSCs group and ADM group. 4 weeks after transplantation, the rats’ cardiac function indexes were detected and the levels of MMP-2 and MMP-9 was measured by western blot. Echocardiography analysis showed significant differences between groups (except LVDd) (P < 0.05). BMSCs and ADM groups had significantly lower LVEF and LVFS levels than control group (P < 0.05) with a significantly higher level in ADM group than BMSCs group (P < 0.05). However, BMSCs and ADM groups presented a significantly higher LVDs (P < 0.05) without difference between them (P > 0.05). Interestingly, no difference of LVDd was found among groups (P > 0.05). MMP-2 and MMP-9 levels in BMSCs group were 0.389±0.021, 0.512±0.018, respectively, which were significantly elevated compared to control group (P < 0.05); MMP-2 and MMP-9 protein level in the ADM group was 0.440±0.018 and 0.539±0.032 respectively, which was significantly higher than control group (P < 0.05). Compared with BMSCs group, ADM group had significantly increased protein levels of MMP-2/9 (P < 0.05). In conclusion, ADM-modified BMSCs transplantation can significantly inhibit MMP-2 and MMP-9 level, thereby improving the heart function of rats with heart failure.

Adrenomedullin is a biological marker of heart failure: review of modern literature
 Amina M. Alieva*1, Natalia

It has been proven that in patients with heart failure (HF), there is an increased level of adrenomedullin (ADM) in plasma. Biomarker indices correlate with the severity of hemodynamic dysfunction, as well as with neurohumoral indices, which are activated depending on the severity of congestive circulatory failure. In addition, the expression of the ADM gene in the heart and kidneys is increased in experimental and clinical HF. A small number of studies have examined the effect of ADM infusion. These studies have generally shown that hormone infusion has beneficial hemodynamic effects and promotes the maintenance/improvement of renal function, but most of the studies have been short-lived. The available results suggest that increasing ADM levels reduce the negative effects of vasoconstriction and sodium retention. A better understanding of the role of a biological marker in congestive circulatory failure may lead to the development of drugs that target ADM receptors.

Plasma Adrenomedullin, Allelic Variations in the ADM Gene, and Risk for Lower-Limb Amputation in People With Type 2 Diabetes.

Patients with diabetes have an increased risk for lower-limb amputation (LLA), but biomarkers to assess risk of LLA are lacking. Adrenomedullin (ADM) is a vasodilator peptide that also plays a role in fluid and electrolyte homeostasis in the kidney, increasing natriuresis and diuresis. ADM was shown to be associated with cardiovascular and renal events in diabetes, but it was not investigated in terms of LLA risk. We investigated the hypothesis that ADM is associated with LLA in people with type 2 diabetes. We studied 4,375 participants in the DIABHYCAR and SURDIAGENE cohorts (men, 68%; mean 66 years of age; mean duration of diabetes 12 years; and median follow-up 5.3 years). Plasma midregional proadrenomedullin (MR-proADM; a surrogate for ADM) was measured by immunofluorescence. Five single nucleotide polymorphisms (SNPs) in the ADM gene region were genotyped. LLA requirement during follow-up by increasing tertiles of plasma MR-proADM distribution was 1.0% (tertile 1 [T1]), 2.3% (T2), and 4.4% (T3) (P < 0.0001). In Cox multivariate analysis, the adjusted hazard ratio (95% CI) for LLA was 4.40 (2.30-8.88) (P < 0.0001) for T3 versus T1. Moreover, MR-proADM significantly improved indices for risk stratification of LLA. Four SNPs were associated with plasma MR-proADM concentration at baseline and with LLA during follow-up. Alleles associated with higher MR-proADM were associated with increased LLA risk. We observed associations of plasma MR-proADM with LLA and of ADM SNPs with plasma MR-proADM and with LLA in people with type 2 diabetes. This pattern of Mendelian randomization supports the causality of the association of ADM with LLA.

Extracellular ATP promotes breast cancer chemoresistance via HIF-1\u03b1 signaling

We have previously demonstrated that extracellular adenosine 5'-triphosphate (ATP) promotes breast cancer cell chemoresistance. However, the underlying mechanism remains unclear. Using a cDNA microarray, we demonstrated that extracellular ATP can stimulate hypoxia-inducible factor (HIF) signaling. In this study, we report that hypoxia-inducible factor 1α (HIF-1α) was upregulated after ATP treatment and mediated the ATP-driven chemoresistance process. We aimed to investigate the mechanisms and identify potential clinically relevant targets that are involved. Using mass spectrometry, we found that aldolase A (ALDOA) interacts with HIF-1α and increases HIF-1α expression. We then demonstrated that STAT3-ALDOA mediates ATP-HIF-1α signaling and upregulates the HIF-1 target genes adrenomedullin (ADM) and phosphoinositide-dependent kinase-1 (PDK1). Moreover, we show that PI3K/AKT acts upstream of HIF-1α in ATP signaling and contributes to chemoresistance in breast cancer cells. In addition, HIF-1α-knockdown or treatment with direct HIF inhibitors combined with the ATP hydrolase apyrase in MDA-MB-231 cells induced enhanced drug sensitivity in nude BALB/c mice. We then used in vitro spheroid formation assays to demonstrate the significance of ATP-HIF-1α in mediating chemoresistance. Furthermore, considering that indirect HIF inhibitors are effective in clinical cancer therapy, we treated tumor-bearing BALB/c mice with STAT3 and PI3K/AKT inhibitors and found that the dual-targeting strategy sensitized breast cancer to cisplatin. Finally, using breast cancer tissue microarrays, we found that ATP-HIF-1α signaling is associated with cancer progression, poor prognosis, and resistance to chemotherapy. Taken together, we suggest that HIF-1α signaling is vital in ATP-driven chemoresistance and may serve as a potential target for breast cancer therapies.

220-OR: Plasma Adrenomedullin and Allelic Variation in the ADM Gene and Risk for Lower Extremity Amputation in People with Type 2 Diabetes

Patients with diabetes have an increased risk for lower limb amputation (LLA) but biomarker to assess risk of LLA is lacking. Adrenomedullin (ADM), a vasodilator peptide, has been shown to be associated with cardiovascular and renal risk in diabetes. The aim of this study is to assess the association between plasma MR-proADM (a surrogate of ADM), allelic variation in the ADM gene and the risk for LLA in cohorts of patients with type 2 diabetes. We studied 4532 participants of the DIABHYCAR and SURDIAGENE cohorts (men 70%, mean age 66, mean duration of diabetes 13 years, A1c 8,0%). MR-proADM was measured by immunofluorescence. Five SNPs were chosen in the haplotype block containing the ADM gene (chr11p15.4): rs4399321, rs11042725, rs7944706, rs2957692 and rs2957717. The mean follow-up was 5.3 years. Incidence of LLA by tertiles of MR-proADM (T1, T2, T3) was 1.0% (T1), 1.9% (T2) et 4.7% (T3) (p&amp;lt;0,001). In a Cox multivariable analysis model (adjusted for cohort, age, sex, diabetes duration, hypertension, A1c, cholesterol, history of peripheral arterial disease and glomerular filtration rate eGFR), HR for LLA was 4.21 (2.18-8.66; p&amp;lt;0.001) for T3 vs. T1, 2.46 (1.50-4.12; p=0.003) for T3 vs. T2 and 1.82 (1.25-2.67; p=0.002) for 1 unit of log [ADM]. All SNPs were significantly associated with baseline plasma ADM. Four were significantly associated with LLA: HR adjusted for sex, age, duration of diabetes, A1c, eGFR and cohort: 1.40 (1.046 - 1.84; p=0.02) for the G-allele of rs4399321 in a codominant model; 1.71 (1.13 - 2.54; p=0.01) for the AA vs. CX genotype of rs11042725; 1.61 (1.09 - 2.35; p=0.02, for the GG vs. AX genotype of rs7944706; 1.37 (1.06 - 1.77; p=0.04) for the G-allele of rs2957692 in a codominant model. We observed an association of plasma ADM with LLA and of allelic variations in the AMP locus with plasma ADM and with LLA in a large population of people with type 2 diabetes. This pattern of mendelian randomisation supports the causality of the association of plasma ADM with LLA. Disclosure L. Potier: Consultant; Self; Eli Lilly and Company, Novo Nordisk A/S, Sanofi. R. Roussel: Advisory Panel; Self; Abbott, AstraZeneca, Diabnext, Eli Lilly and Company, Merck &amp; Co., Inc., Mundipharma International, Novo Nordisk A/S, Sanofi-Aventis. P. Saulnier: None. F. Fumeron: None. K. Mohammedi: None. G. Velho: None.

Adrenomedullin expression in aortic artery wall of diabetic rats given alpha lipoic acid.

Diabetes mellitus (DM) is a major health problem predisposing to cardiovascular diseases. The aim of this study was to investigate the effects of alpha lipoic acid (ALA) on both the arterial wall of diabetic rats and the adrenomedullin (ADM) gene expression. Twenty-four Wistar Albino rats were divided into three groups as Control, DM + S, and DM + ALA. For DM model, a single dose of 40mg/kg streptozotocin, for DM + ALA group, 100mg/kg/day/4weeks was administered. Hematoxylin & Eosin (H&E) staining was done and vascular endothelial growth factor (VEGF) was detected by immunohistochemical analysis in the artery wall. Total damage score of vessel wall (endothelial cell damage, media layer smooth muscle cell damage, and internal elastic lamina damage) and H score (immunoreactivity intensity) were calculated. Expression of ADM gene was measured by qRT-PCR. In DM + S group, Total damage score of vessel wall were detected by light microscopy. There were statistically significant differences between the groups Control/DM + S and DM + S/DM + ALA in terms of the vessel total damage score and H score (p < 0.005). ADM expression was increased threefold in both DM + S and DM + ALA groups compared to the control group (p < 0.05). ALA may have positive effect on the vessel damage in diabetic rats. However, no significant decrease in ADM expression levels was observed in diabetic rats after ALA administration and we considered that the protective effect of ALA is independent of adrenomedullin. Further studies with different doses and durations of ALA administrations are required to investigate the changes in ADM expression.

Adrenomedullin has a role in angiogenic effects of resveratrol in adipose tissues of obese female rats.

Obesity is a complex, chronic disease that arises according to the interaction between genetic and environmental factors. The expansion and growth of white adipose tissue (WAT) could be related to angiogenesis. Resveratrol and adrenomedullin (AdM) were used for the inhibition of angiogenesis in metabolically passive WAT for inhibiting the expansion of this tissue, and the activation of angiogenesis in metabolically active brown adipose tissue (BAT) for increasing daily energy consumption as a way of reducing obesity. Rats were divided into eight groups. Four obese groups were fed with a high-fat diet containing 60% fat as energy for three months. After obtaining obesity, 2.5nmol/kg AdM and 10mg/kg resveratrol were treated to experiment groups intraperitoneally (i.p.) every other day for four weeks. AdM and vascular endothelial growth factor A (VEGF-A) mRNA levels were detected with semi-quantitative PCR; protein levels were detected with Western Blotting. AdM and resveratrol are multifactorial molecules, thus, this study has revealed a few novel evidence. The results were distinct in the group and treatment levels. The results showed that resveratrol has a role in angiogenesis in obesity and contributed to AdM production. It is observed that AdM has regulated its expression and increased the effect of resveratrol in WAT. AdM and VEGF-A gene expressions could not be detected in BAT; however, it is suggested that resveratrol may have a pro-angiogenic effect in BAT of obese rats according to the protein levels. AdM also has regulated VEGF-A level according to the metabolic situation of the organism.

Expression of human adrenomedullin gene in gastric adenocarcinoma and construction and identification of adrenomedullin overexpression vector and adrenomedullin-shRNA vector

Expression of human adrenomedullin gene in gastric adenocarcinoma and construction and identification of adrenomedullin overexpression vector and adrenomedullin-shRNA vector

Key Regulatory Effect of Activated HIF-1α/VEGFA Signaling Pathway in Systemic Capillary Leak Syndrome Confirmed by Bioinformatics Analysis

Systemic capillary leak syndrome (SCLS) is a rare disorder characterized by capillary leakage of plasma fluids throughout the endothelium. The mechanism of SCLS is still unknown. Vascular endothelial growth factor (VEGF), an inducer or barrier disruption, is markedly upregulated in SCLS. This study was to investigate the molecular mechanisms involving SCLS-related inflammation and neuron damage in SCLS remain unclear. Data files of GSE97287 dataset were extracted and processed for identification of differentially expressed genes (DEGs), including upregulated adrenomedullin (ADM) gene, hypoxia-inducible factor-1α (HIF-1α) and VEGFA; and downregulated aldehyde dehydrogenase 1A1 (ALDH1A1) gene and interleukin (IL)-2 receptor β (IL-2RB) gene. Weighted gene coexpression network analysis (WGCNA) was performed for DEGs and four significant modules were identified and were enriched Gene Ontology (GO) biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to immune response, angiogenesis, neuroblast proliferation, HIF-1 signaling pathway, and Parkinson's disease. The activated HIF-1α/VEGFA signaling in SCLS patients might well be responsible for the impaired inflammatory, nervous, and immune systems.

Associations of the adrenomedullin gene polymorphism with prehypertension and hypertension in Lithuanian children and adolescents: a cross-sectional study

The aim of this study was to evaluate the association of ADM genetic variant and HBP among Lithuanian adolescents aged 12–15 years. This is a cross-sectional study of a randomly selected sample of 675 12–15-years-old schoolchildren who were surveyed during November 2010 to April 2012 in the baseline survey. Single-nucleotide polymorphism (SNP) of ADM gene (rs7129220) was evaluated using real-time PCR. Logistic regression analyses were used to test the associations of ADM (rs7129220) polymorphism with HBP under four inheritance models based on the Akaike Information Criterion (AIC) and to calculate the odds ratios. In the multivariate analysis, boys carrying ADM AG genotype (vs. carriers of ADM GG genotype), ADM AG + AA genotype (vs. carriers of ADM GG genotype) and ADM AG genotype (vs. carriers of ADM GG + AA genotype) had higher odds of having hypertension in codominant, dominant, and overdominant inheritance models. Girls with ADM AG + AA had increased odds of prehypertension compared to girls with the ADM GG genotype carriers in dominant inheritance model. Significant associations were observed in additive models separately for boys (hypertension) and girls (prehypertension). Our results indicate that ADM gene polymorphism was significantly associated with higher odds of HBP in Lithuanian adolescents aged 12–15 years.

Adrenomedullin gene polymorphisms ( rs4399321A/G and rs4910118C/T ) in pregnancy related disorder: Preeclampsia

Preeclampsia (PE), a pregnancy specific vascular disorder which is characterized by hypertension and proteinuria is a leading cause of maternal, fetal/neonatal morbidity and mortality affecting 5-14% of pregnancies. PE is a multifactorial disorder associated with poor placentation, placental hypoxia, poor angiogenesis and excessive maternal inflammation. Adrenomedullin (ADM) is a multifunctional peptide, plays an important role in the establishment and maintenance of healthy pregnancy, prevents an immune attack at peri-implantation period, vasodilation and promotes angiogenesis. In the present study, we enrolled a total of 600 subjects which includes 300 PE patients and 300 healthy pregnant women from South India to analyse two functional polymorphisms (rs4399321A/G and rs4910118C/T) of ADM gene. The genotype frequencies of these two polymorphisms differed significantly between the PE and control groups (p=0.02 and p=0.03). Individuals carrying the AA genotype of rs4399321A/G were slightly higher in controls (40%) compared to patients (28%) and revealed an OR value of (0.69, CI 0.49-0.98; p=0.05) suggests the protective role. Predominant frequency of CC genotype of rs4910118C/T was observed in patients (OR- 1.43; CI 1.02–2.01, p=0.04) and CT genotype in controls (OR-0.69; CI 0.49–0.97, p=0.04) indicating predisposing and protective role of these genotypes. Haplotype analysis revealed a substantial association of A-T block towards preeclampsia with an OR value of 0.40 (CI 0.21-0.75, p=0.004). Further analysis on linkage disequilibrium showed a significant value (D’=1.0 and r2=0.12, p<0.05) between these two polymorphisms.

Reduced Adrenomedullin Parallels Microtubule Dismantlement in Frontotemporal Lobar Degeneration.

Tau is a microtubule-associated protein highly expressed in neurons with a chief role in microtubule dynamics and axonal maintenance. Adrenomedullin gene (ADM) codifies for various peptides that exert broad range of actions in the body. Previous works in our groups have shown that increased ADM products are positively correlated to microtubule disruption and tau pathology in Alzheimer's disease brains. In the present study, we explore the involvement of ADM in the neuropathology of frontotemporal lobar degeneration that presents with primary tauopathy (FTLD-tau). Proteins from frontal cortices of FTLD-tau patients and age- and sex-matched non-demented controls were analyzed with antibodies against different microtubule components, including adrenomedullin, and synaptic markers. Tau pathology in frontal cortex from FTLD patients was confirmed. Levels of total βIII-tubulin as well as acetylated and detyrosinated tubulins, two markers of stabilized and aged microtubules, were significantly reduced and directly correlated with PSD95 and proBDNF in FTLD-tau patients when compared to non-demented controls. In contrast, no change in actin cytoskeleton was found. Interestingly, changes in microtubule elements, indicators of disturbed axonal preservation, were accompanied by decreased levels of free adrenomedullin, although no association was found. Altogether, reduced levels of adrenomedullin might not be directly linked to the microtubule pathology of FTLD-tau, but based on previous works, it is suggested that downregulation of ADM might be an adaptive attempt of neurons to mitigate microtubule disruption.

Overexpression of adrenomedullin protects mesenchymal stem cells against hypoxia and serum deprivation‑induced apoptosis via the Akt/GSK3β and Bcl‑2 signaling pathways.

The poor survival rate of transplanted mesenchymal stem cells (MSCs) within the ischemic heart limits their therapeutic potential for cardiac repair. Adrenomedullin (ADM) has been identified as a potent apoptotic inhibitor. The present study aimed to investigate the protective effects of ADM on MSCs against hypoxia and serum deprivation (H/SD)-induced apoptosis, and to determine the potential underlying mechanisms. In the present study, a recombinant adenovirus expressing the ADM gene was established and was infected into MSCs. The infection rate was determined via microscopic detection of green fluorescence and flow cytometric analysis. The mRNA expression levels of ADM were detected by reverse transcription-polymerase chain reaction. In addition, a model of H/SD was generated. The MSCs were randomly separated into six groups: Control, enhanced green fluorescent protein (EGFP)-Adv, EGFP-ADM, H/SD, EGFP-Adv + H/SD and EGFP-ADM + H/SD. Cell viability and proliferation were determined using the Cell Counting kit-8 assay. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated-dUTP nick-end labeling assay and flow cytometric analysis using Annexin V-phycoerythrin/7-aminoactinomycin D staining. The protein expression levels of total protein kinase B (Akt), phosphorylated (p)-Akt, total glycogen synthase kinase (GSK)3β, p-GSK3β, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3 and cleaved caspase-3 were detected by western blot analysis. The results indicated that ADM overexpression could improve MSC proliferation and viability, and protect MSCs against H/SD-induced apoptosis. In addition, ADM overexpression increased Akt and GSK3β phosphorylation, and Bcl-2/Bax ratio, and decreased the activation of caspase-3. These results suggested that ADM protects MSCs against H/SD-induced apoptosis, which may be mediated via the Akt/GSK3β and Bcl-2 signaling pathways.

Lack of Adrenomedullin Aggravates Acute TNBS-Induced Colitis Symptoms in Mice, Especially in Females.

Adrenomedullin (AM) is a biologically active peptide which has been tested as a new therapy for inflammatory bowel disease (IBD) in animal models and in patients with severe ulcerative colitis. We used an inducible knockout (KO) mouse model for AM to evaluate the effects of endogenous levels of this peptide on the development and degree of pathogenesis of IBD. Acute colitis was induced in mice of both sexes by rectal instillation of 3 mg 2,4,6-trinitrobenzenesulfonic acid (TNBS) in 100 μL of 50% ethanol. Control mice received the same volume of saline in 50% ethanol. During the following 5 days, the weight and the disease severity index of all animals were recorded. After sacrifice, the inflammatory response was macroscopically assessed by analyzing the weight of the colon; by histomorphometrical analysis on histological sections; and by qRT-PCR determination of different inflammatory, adhesion, and regeneration molecules. TNBS administration caused a significantly more severe colitis in KO mice, and especially in females, when compared to wild type (WT) animals. Abrogation of the AM gene caused more severe diarrhea, accompanied by rectal bleeding, anorexia, and a significant increase of colon weight. Histological analysis of TNBS-treated KO mice showed large areas of lymphocyte infiltrates in the mucosa and submucosa, with loss of tissue architecture. No alterations were observed in the expression levels of inflammatory cytokines at the time of sacrifice; meanwhile lack of AM resulted in lower levels of some adhesion molecules and regeneration markers. Taken together, these results support the protective role of endogenous AM against the development of acute colitis, and that its effects are particularly beneficial on females.

Identification of key pathogenic genes of sepsis based on the Gene Expression Omnibus database.

Sepsis is a life-threatening condition in which an uncontrolled inflammatory host response is triggered. The exact pathogenesis of sepsis remains unclear. The aim of the present study was to identify key genes that may aid in the diagnosis and treatment of sepsis. mRNA expression data from blood samples taken from patients with sepsis and healthy individuals was downloaded from the Gene Expression Omnibus database and differentially expressed genes (DEGs) between the two groups were identified. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction (PPI) network construction, was performed to investigate the function of the identified DEGs. Furthermore, for validation of these results, the expression levels of several DEGs were analyzed by reverse transcription quantitative-polymerase chain reaction (RT-qPCR) in three patients with sepsis and three healthy blood samples to support the results obtained from the bioinformatics analysis. Receiver operating characteristic analyses were also used to analyze the diagnostic ability of the identified DEGs for sepsis. The results demonstrated that a total of 4,402 DEGs, including 1,960 upregulated and 2,442 downregulated genes, were identified between patients with sepsis and healthy individuals. KEGG pathway analysis revealed that 39 DEGs were significantly enriched in toll-like receptor signaling pathways. The top 20 upregulated and downregulated DEGs were used to construct the PPI network. Hub genes with high degrees, including interleukin 1 receptor-associated kinase 3 (IRAK3), S100 calcium-binding protein (S100)A8, angiotensin II receptor-associated protein (AGTRAP) and S100A9, were demonstrated to be associated sepsis. Furthermore, RT-qPCR results demonstrated that IRAK3, adrenomedullin (ADM), arachidonate 5-lipoxygenase (ALOX5), matrix metallopeptidase 9 (MMP9) and S100A8 were significantly upregulated, while ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1) was upregulated but not significantly, in blood samples from patients with sepsis compared with healthy individuals, which was consistent with bioinformatics analysis results. Therefore, AGTRAP, IRAK3, ADM, ALOX5, MMP9, S100A8 and ENTPD1 were identified to have potential diagnostic value in sepsis. In conclusion, dysregulated levels of the AGTRAP, IRAK3, ADM, ALOX5, MMP9, S100A8 and ENTPD1 genes may be involved in sepsis pathophysiology and may be utilized as potential diagnostic biomarkers or therapeutic targets.