Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

Establishment of a typing model for diffuse large B-cell lymphoma based on B-cell receptor repertoire sequencing

BACKGROUND

The purpose of this study was to construct a new typing model for diffuse large B-cell lymphoma (DLBCL) patients based on the B-cell receptor (BCR) and explore its potential molecular mechanism.

METHODS

BCR repertoire sequencing and whole-exome sequencing were performed on formalin-fixed paraffin-embedded samples from 12 DLBCL patients. Subsequently, a typing model was built with cluster analysis, and prognostic indicators between the two groups were compared to verify the typing model. Then, mutation and bioinformatics analyses were conducted to investigate the potential biomarkers of prognostic differences between the two groups.

RESULTS

Based on BCR sequencing data, we divided patients into two clusters (cluster 1 and cluster 2); this classification differed from the traditional typing method (GCB and non-GCB), in which cluster 1 included some non-GCB patients. The progression-free survival (PFS), overall survival (OS), metastasis and Shannon diversity index of IGH V-J and survival after chemotherapy were significantly different (P < 0.05) between the two clusters, but no statistical significance was found between the GCB and non-GCB groups. The mutation status of 248 genes was significantly different between cluster 1 and cluster 2. Among them, FTSJ3, MAGED2, and ODF3L2 were the specific mutated genes in all patients in cluster 2, and these genes could be considered critical to the different prognoses of the two clusters of DLBCL patients.

CONCLUSION

We constructed a new typing model of DLBCL based on BCR repertoire sequencing that can better predict the survival time after chemotherapy. FTSJ3, MAGED2, and ODF3L2 may represent key genes for the difference in prognosis between the two clusters.

Prediction of Clinical Outcome in Patients with Large-Vessel Acute Ischemic Stroke: Performance of Machine Learning versus SPAN-100

BACKGROUND AND PURPOSE

Traditional statistical models and pretreatment scoring systems have been used to predict the outcome for acute ischemic stroke patients (AIS). Our aim was to select the most relevant features in terms of outcome prediction on the basis of machine learning algorithms for patients with acute ischemic stroke and to compare the performance between multiple models and the Stroke Prognostication Using Age and National Institutes of Health Stroke Scale (SPAN-100) index model.

MATERIALS AND METHODS

A retrospective multicenter cohort of 1431 patients with acute ischemic stroke was subdivided into recanalized and nonrecanalized patients. Extreme Gradient Boosting machine learning models were built to predict the mRS score at 90 days using clinical, imaging, combined, and best-performing features. Feature selection was performed using the relative weight and frequency of occurrence in the models. The model with the best performance was compared with the SPAN-100 index model using area under the receiver operating curve analysis.

RESULTS

In 3 groups of patients, the baseline NIHSS was the most significant predictor of outcome among all the parameters, with relative weights of 0.36∼0.69; ischemic core volume on CTP ranked as the most important imaging biomarker with relative weights of 0.29∼0.47. The model with the best-performing features had a better performance than the other machine learning models. The area under the curve of the model with the best-performing features was higher than SPAN-100 model and reached statistical significance for the total (P < .05) and the nonrecanalized patients (P < .001).

CONCLUSIONS

Machine learning-based feature selection can identify parameters with higher performance in outcome prediction. Machine learning models with the best-performing features, especially advanced CTP data, had superior performance of the recovery outcome prediction for patients with stroke at admission in comparison with SPAN-100.

Risk Factors and Outcomes of Antibiotic-resistant Pseudomonas aeruginosa Bloodstream Infection in Adult Patients With Acute Leukemia

BACKGROUND

Pseudomonas aeruginosa (PA) bloodstream infection (BSI) is a common complication in patients with acute leukemia (AL), and the prevalence of antibiotic-resistant strains poses a serious problem. However, there is limited information regarding antibiotic resistance, clinical characteristics, and outcomes of PA BSI in AL patients. This study explored characteristics associated with the clinical outcomes of AL patients with PA BSI and analyzed factors associated with BSI caused by multidrug-resistant (MDR) or carbapenem-resistant strains.

METHODS

This single-center retrospective study enrolled hospitalized AL patients who developed PA BSI during January 2014-December 2019. The Kaplan-Meier method was used to plot survival curves. Multivariate logistic regression analyses were also performed.

RESULTS

Of 293 eligible patients with PA BSI, 55 (18.8%) received inappropriate empirical antibiotic therapy within 48 hours of BSI onset, whereas up to 65.8% MDR-PA BSI patients received inappropriate empirical treatment. The 30-day mortality rate was 8.5% for all patients. However, the 30-day mortality rates were 28.9% and 5.5% in MDR-PA BSI and non-MDR-PA BSI patients, respectively (P < .001). On multivariate analysis, previous use of quinolones (odds ratio [OR], 5.851 [95% confidence interval {CI}, 2.638-12.975]) and piperacillin/tazobactam (OR, 2.837 [95% CI, 1.151-6.994]) were independently associated with MDR-PA BSI; and MDR-PA BSI (OR, 7.196 [95% CI, 2.773-18.668]), perianal infection (OR, 4.079 [95% CI, 1.401-11.879]), pulmonary infection (OR, 3.028 [95% CI, 1.231-7.446]), and age ≥55 years (OR, 2.871 [95% CI, 1.057-7.799]) were independent risk factors for 30-day mortality.

CONCLUSIONS

MDR increases mortality risk in PA BSI patients, and previous antibiotic exposure is important in MDR-PA BSI development. Rational antibiotic use based on local antimicrobial susceptibility and clinical characteristics can help reduce antibiotic resistance and mortality.

Clinical characteristics and predictors of the duration of SARS-CoV-2 viral shedding in 140 healthcare workers

BACKGROUND

Epidemiological and clinical features of patients with COVID-19 have been reported, but none of them focused on medical staff, and few predictors of the duration of viral shedding have been reported. It is urgent to help healthcare workers prevent and recover quickly from the coronavirus disease 2019 (COVID-19).

METHODS

We enrolled 140 medical workers with COVID-19 in Wuhan. Epidemiological, demographic, clinical, laboratory, radiological treatment and clinical outcome data were collected, and predictors of the duration of viral shedding were explored through multivariable linear regression analysis.

RESULTS

The medical staff with COVID-19 presented mild clinical symptoms and showed a low frequency of abnormal laboratory indicators. All the medical staff were cured and discharged, of whom 96 (68.6%) were female, 39 (27.9%) had underlying diseases, the median age was 36.0 years, and 104 (74.3%) were infected whilst working in hospital. The median duration of viral shedding was 25.0 days (IQR:20.0-30.0). Multivariable linear regression analysis showed reducing viral shedding duration was associated with receiving recombinant human interferon alpha (rIFN-α) treatment, whilst the prolonged duration of viral shedding correlated with the use of glucocorticoid treatment, the durations from the first symptom to hospital admission and the improvement in chest computed tomography (CT) evidence. Moreover, infected healthcare workers with lymphocytes less than 1.1 × 10⁹ /L on admission had prolonged viral shedding.

CONCLUSION

Medical staff with timely medical interventions show milder clinical features. Glucocorticoid treatment and lymphocytes less than 1.1 × 109/L are associated with prolonged viral shedding. Early admission and rIFN-α treatment help shorten the duration of viral shedding.

PHACTR1, a pro-atherosclerotic mechanosensitive PPARgamma corepressor in endothelial cells

Background

Numerous genome-wide association studies revealed that SNPs at phosphatase and actin regulator 1 (PHACTR1) locus are strongly correlated with coronary artery disease (CAD). However, the mechanism linking these variants to CAD remains uncertain.

Purpose

We studied the biological functions and molecular mechanisms of PHACTR1 in atherosclerosis.

Methods and results

Analysis of GTEx database showed that CAD-related SNPs in PHACTR1 are cis-eQTLs for PHACTR1 in arteries. Therefore, we generated Phactr1 knockout mice and crossed them with apolipoprotein E-deficient (ApoE−/−) mice to induce atherosclerosis by high-fat/high-cholesterol (HF-HC) diet. Phactr1 deficiency significantly inhibited atherosclerosis with decreased inflammatory cell infiltration. Western blot showed that PHACTR1 was restricted to endothelial cells (ECs) in mice. Mechanistically, RNAseq of aortic ECs revealed that the major molecular function of PHACTR1 was transcriptional regulation. PPARγ/RXRα was the top transcription factor, and PPARγ target gene expression substantially increased in Phactr1−/− mice. Moreover, we generated endothelial cell specific Phactr1−/−, ApoE−/− mice and found decreased atherosclerotic plaque area in aortic sinus. In vitro, PHACTR1 associated with PPARγ and inhibited PPARγ transcriptional activity. The inhibitory effect of PHACTR1 on PPARγ required its shuttling from cytosol to nucleus triggered by disturbed flow, a well-established pro-atherosclerotic stimulus.

Conclusion

Our results identified PHACTR1 as a mechanosensitive corepressor of PPARγ in ECs to promote atherosclerosis. Endothelial PHACTR1 is a potential therapeutic target for atherosclerosis treatment.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China (NSFC), China Postdoctoral Science Foundation (CPSF)

Aberrant Exon 8/8a Splicing by Downregulated PTBP (Polypyrimidine Tract-Binding Protein) 1 Increases CaV1.2 Dihydropyridine Resistance to Attenuate Vasodilation

OBJECTIVE

Calcium channel blockers, such as dihydropyridines, are commonly used to inhibit enhanced activity of vascular Ca_V1.2 channels in hypertension. However, patients who are insensitive to such treatments develop calcium channel blocker-resistant hypertension. The function of Ca_V1.2 channel is diversified by alternative splicing, and the splicing factor PTBP (polypyrimidine tract-binding protein) 1 influences the utilization of mutually exclusive exon 8/8a of the Ca_V1.2 channel during neuronal development. Nevertheless, whether and how PTBP1 makes a role in the calcium channel blocker sensitivity of vascular Ca_V1.2 channels, and calcium channel blocker-induced vasodilation remains unknown. Approach and Results: We detected high expression of PTBP1 and, inversely, low expression of exon 8a in Ca_V1.2 channels (Ca_V1.2_E8a) in rat arteries. In contrast, the opposite expression patterns were observed in brain and heart tissues. In comparison to normotensive rats, the expressions of PTBP1 and Ca_V1.2_E8a channels were dysregulated in mesenteric arteries of hypertensive rats. Notably, PTBP1 expression was significantly downregulated, and Ca_V1.2_E8a channels were aberrantly increased in dihydropyridine-resistant arteries compared with dihydropyridine-sensitive arteries of rats and human. In rat vascular smooth muscle cells, PTBP1 knockdown resulted in shifting of Ca_V1.2 exon 8 to 8a. Using patch-clamp recordings, we demonstrated a concomitant reduction of sensitivity of Ca_V1.2 channels to nifedipine, due to the higher expression of Ca_V1.2_E8a isoform. In vascular myography experiments, small interfering RNA-mediated knockdown of PTBP1 attenuated nifedipine-induced vasodilation of rat mesenteric arteries.

CONCLUSIONS

PTBP1 finely modulates the sensitivities of Ca_V1.2 channels to dihydropyridine by shifting the utilization of exon 8/8a and resulting in changes of responses in dihydropyridine-induced vasodilation.

Glycochenodeoxycholic acid induces stemness and chemoresistance via the STAT3 signaling pathway in hepatocellular carcinoma cells

The poor prognosis of hepatocellular carcinoma (HCC) is primarily attributed to its high frequency of recurrence and resistance to chemotherapy. Epithelial-to-mesenchymal transition (EMT) and the acquisition of cancer stem cells (CSCs) are the fundamental drivers of chemoresistance in HCC. Glycochenodeoxycholic acid (GCDC), a component of bile acid (BA), has been reported to induce necrosis in primary human hepatocytes. In the present work, we investigated the function of GCDC in HCC chemoresistance. We found that GCDC promoted chemoresistance in HCC cells by down-regulating and up-regulating the expression of apoptotic and anti-apoptotic genes, respectively. Furthermore, GCDC induced the EMT phenotype and stemness in HCC cells and activated the STAT3 signaling pathway. These findings reveal that GCDC promotes chemoresistance in HCC by inducing stemness via the STAT3 pathway and could be a potential target in HCC chemotherapy.

Association study of SNCA gene polymorphisms with schizophrenia in a Chinese North Han population

OBJECTIVE

Previous studies suggested that the alpha-synapse protein (SNCA) gene and its coding product α-synuclein (α-Syn) may play a role in the pathogenesis of neurodegenerative diseases. The mutation of SNCA can influence the formation of nerve fibers and the function of dopaminergic neurons, and that may be related to addictive behavior, such as alcohol dependence. SNCA may overlap with the pathogenesis of schizophrenia and Parkinson's disease or alcohol dependence associated with the dopamine pathway. The aim was to determine the association between three SNCA SNPs (rs3822086C/T, rs11931074G/T, and rs356219A/G) and schizophrenia in a Chinese North Han population.

PATIENTS AND METHODS

A total of 878 subjects, with or without schizophrenia, were included in our study. DNA purification, Polymerase Chain Reaction (PCR) amplification, and subsequent restriction fragment length polymorphism (RFLP) analysis were manipulated to determine genotypes.

RESULTS

Between the schizophrenia group and healthy group, neither the genotype nor allele frequencies of rs3822086C/T, rs11931074G/T, or rs356219A/G differed significantly in either the total sample or the subgroups. In the haplotype analysis, the ATT and GTT haplotype frequencies differed significantly between the patients and controls in the total sample (χ2=6.052, p=0.0139; χ2=4.508, p=0.0337). In the female subgroup, the ATT haplotype frequency differed significantly between the patients and controls (χ2=4.219, p=0.04).

CONCLUSIONS

There was no association between SNCA polymorphisms and schizophrenia in the North Han Chinese population, and the ATT haplotype may be a susceptibility factor for schizophrenia.

Self-made Salmonella Pullorum agglutination antigen development and its potential practical application

Pullorum disease caused by Salmonella Pullorum is one of the most important infectious diseases in the poultry industry worldwide, which leads to serious economic losses in many developing countries because of its high mortality rate in young chicks. The traditional slide agglutination test with low cost, fast reaction, and on-site detection has been widely used in the diagnosis of Pullorum disease. However, in practice, the test performance is with the disadvantages of false positive results and unstable detection results. In this paper, we developed self-made agglutination antigens prepared by local isolates in the poultry farm and compare the detection performance with commercial agglutination antigens (China Institute of Veterinary Drug Control) and Group D Salmonella ELISA kit (BioChek UK Ltd). The results of detecting 200 serum samples indicated that the consistency of commercial agglutination antigen detecting in 2 times was only 79.5%. Using the ELISA kit as the reference method, the commercial agglutination antigen detecting results of the Kappa test were only moderately consistent (0.58 ∼ 0.59). Meanwhile, positive and total coincidence rates of the self-made agglutination antigen test with more reliable repeat could reach 97.4 and 88%, respectively, and the result of Kappa test was highly consistent (0.75). The Receiver Operating Characteristic curve analysis clarified that the area under the receiver-operating-characteristic curve values of self-made and commercial agglutination antigen tests could reach 0.861 and 0.804, respectively. These results were coincident when detecting known positive serum from the infected chickens. It's worth mentioning that the visible positive reaction of self-made agglutination antigen test appeared faster and stronger than commercial antigen test. In conclusion, self-made Salmonella Pullorum agglutination antigen developed in this study was much better than commercial agglutination antigen and is expected to be a valuable tool in the diagnosis of the epidemiology of Salmonella Pullorum.

Chinese expert group consensus on diagnosis and clinical management of osteoradionecrosis of the mandible

Osteoradionecrosis of the mandible (MORN) is one of the most devastating complications caused by radiation therapy in the head and neck region. It is characterized by infection and chronic necrosis of the mandible as the main manifestation. Clinically, MORN-related symptoms include swelling, pain, dysphagia, trismus, masticatory or speech disorders, refractory orocutaneous fistula, bone exposure, and even pathological fracture. MORN has become a challenging clinical problem for oral and maxillofacial surgeons to deal with, but thus far, this problem has not been solved due to the lack of widely accepted treatment algorithms or guidelines. Because of the nonexistence of standardized treatment criteria, most clinical treatment against MORN nowadays is largely based on controversial empirical understandings, while recommendations on post-therapeutic evaluations are scarce. Therefore, to further unify and standardize the diagnosis and treatment of MORN, to decrease the huge waste of medical resources, and ultimately, to improve the wellbeing of the patients, the Chinese Society of Oral and Maxillofacial Surgery (CSOMS) convened an expert panel specialized in MORN from 16 domestic medical colleges and affiliated hospitals to discuss the spectrum of diagnosis and and formulate treatment. In addition, consensus recommendations were also revised with a comprehensive literature review of the previous treatment experiences and research pearls. This 'expert consensus statement on diagnosis and clinical management of MORN' is for clinical reference.

Triad3A attenuates pathological cardiac hypertrophy involving the augmentation of ubiquitination-mediated degradation of TLR4 and TLR9

Activation of TLRs mediated the NF-κB signaling pathway plays an important pathophysiological role in cardiac hypertrophy. Triad3A, a ubiquitin E3 ligase, has been reported to negatively regulate NF-κB activation pathway via promoting ubiquitination and degradation of TLR4 and TLR9 in innate immune cells. The role of Triad3A in cardiac hypertrophic development remains unknown. The present study investigated whether there is a link between Triad3A and TLR4 and TLR9 in pressure overload induced cardiac hypertrophy. We observed that Triad3A levels were markedly reduced following transverse aortic constriction (TAC) induced cardiac hypertrophy. Similarly, stimulation of neonatal rat cardiac myocytes (NRCMs) with angiotensin-II (Ang II) significantly decreased Triad3A expression. To determine the role of Triad3A in TAC-induced cardiac hypertrophy, we transduced the myocardium with adenovirus expressing Triad3A followed by induction of TAC. We observed that increased expression of Triad3A significantly attenuated cardiac hypertrophy and improved cardiac function. To investigate the mechanisms by which Triad3A attenuated cardiac hypertrophy, we examined the Triad3A E3 ubiquitination on TLR4 and TLR9. We found that Triad3A promoted TLR4 and TLR9 degradation through ubiquitination. Triad3A mediated TLR4 and TLR9 degradation resulted in suppression of NF-κB activation. Our data suggest that Triad3A plays a protective role in the development of cardiac hypertrophy, at least through catalyzing ubiquitination-mediated degradation of TLR4 and TLR9, thus negatively regulating NF-κB activation.

Effects of Different Ligands in the Notch Signaling Pathway on the Proliferation and Transdifferentiation of Primary Type II Alveolar Epithelial Cells

Background: Transdifferentiation of type II alveolar epithelial cells (AECII) into type I alveolar epithelial cells (AECI) is involved in neonatal respiratory distress syndrome (NRDS). Different ligands of the Notch pathway could have different effects on AECII transdifferentiation. Objective: To investigate the effects of Dlk1 and Jagged1 on the proliferation and transdifferentiation of AECII. Methods: Fetal AECIIs (19 days of gestation) were divided: control group, Dlk1 group, rhNF-κB group. Proliferation was tested using the MTT assay. Expression of surfactant protein C (SP-C) and aquaporin 5 (AQP5) was examined by immunofluorescence. mRNA and protein levels of SP-C, AQP5, Nortch1, Dlk1, Jagged1, and Hes1 were examined by RT-PCR and western blot. Results: In response to Dlk1, cell number and proliferation were increased (P < 0.05), and mRNA and protein levels of SP-C, Dlk1, Notch1, and Hes1 were up-regulated, while AQP and Jagged1 were decreased. In response to rhNF-κB, the cell number and proliferation were reduced, and mRNA and protein levels of Jagged1 and Notch1 were up-regulated, while Dlk1, and SP-C were downregulated. In the Dlk1 group, SP-C, and AQP5 expression patterns suggested that the cells were still transdifferentiating by 96 h, while in the rhNF-κB group, most cells had transdifferentiated by 72 h and were close to apoptosis by 96 h. Conclusion: These results suggest that Dlk1 promoted proliferation of AECIIs and inhibited cell transdifferentiation, while Jagged1 treatment inhibited proliferation of AECIIs and promoted transdifferentiation to AECIs. These results provide some clue for the eventual management of NDRS.

Autophagy triggered by MAVS inhibits Coxsackievirus A16 replication

Mitochondrial antiviral signaling protein (MAVS), a crucial adaptor protein localized on mitochondria, plays vital roles in various biological processes. Autophagy and apoptosis are two independent and closely linked cell death pathways. But whether MAVS could induce apoptosis and autophagy in rhabdomyosarcoma cells (RD cells) and what is the relationship between autophagy and apoptosis still remains elusive. Here, we reveal that overexpression of MAVS could trigger both apoptosis and autophagy in RD cells. Interestingly, MAVS-induced apoptosis was dependent on the activation of the c-Jun N-terminal kinase (JNK) signaling pathway and inhibition of the extracellular signal-regulated kinase (ERK) signaling pathway. Also, it was found that inhibition of autophagy by 3-methyladenine (3-MA) enhanced MAVS-induced apoptosis resulting in increased cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP). Meanwhile, autophagy induction by rapamycin resulted in decreased MAVS-induced apoptosis. In addition, we found that MAVS expression was inhibited upon Coxsackievirus A16 (CA16) infection and overexpression of MAVS could inhibit CA16 replication. Collectively, our study provides novel insights into the link between apoptosis and autophagy induced by MAVS overexpression in RD cells and gains a greater understanding of MAVS-induced antiviral functions, which provide new targets for CA16 treatment. Keywords: CA16; MAVS; apoptosis; autophagy.

O-GlcNAcylation of YY1 stimulates tumorigenesis in colorectal cancer cells by targeting SLC22A15 and AANAT

Emerging studies have revealed that O-GlcNAcylation plays pivotal roles in the tumorigenesis of colorectal cancers (CRCs). However, the underlying mechanism still remains largely unknown. Here, we demonstrated that Yin Yang 1 (YY1) was O-GlcNAcylated by O-GlcNAc transferase (OGT) and O-GlcNAcylation of YY1 could increase the protein expression by enhancing its stability. O-GlcNAcylation facilitated transformative phenotypes of CRC cell in a YY1-dependent manner. Also, O-GlcNAcylation stimulates YY1-dependent transcriptional activity. Besides, we also identified the oncoproteins, SLC22A15 and AANAT, which were regulated by YY1 directly, are responsible for the YY1 stimulated tumorigenesis. Furthermore, we identified the main putative O-GlcNAc site of YY1 at Thr236, and mutating of this site decreased the pro-tumorigenic capacities of YY1. We concluded that O-GlcNAcylation of YY1 stimulates tumorigenesis in CRC cells by targeting SLC22A15 and AANAT, suggesting that YY1 O-GlcNAcylation might be a potential effective therapeutic target for treating CRC.

Intermedin in Paraventricular Nucleus Attenuates Ang II-Induced Sympathoexcitation through the Inhibition of NADPH Oxidase-Dependent ROS Generation in Obese Rats with Hypertension

Increased reactive oxygen species (ROS) induced by angiotensin II (Ang II) in the paraventricular nucleus (PVN) play a critical role in sympathetic overdrive in hypertension (OH). Intermedin (IMD), a bioactive peptide, has extensive clinically prospects in preventing and treating cardiovascular diseases. The study was designed to test the hypothesis that IMD in the PVN can inhibit the generation of ROS caused by Ang II for attenuating sympathetic nerve activity (SNA) and blood pressure (BP) in rats with obesity-related hypertension (OH). Male Sprague-Dawley rats (160-180 g) were used to induce OH by feeding of a high-fat diet (42% kcal as fat) for 12 weeks. The dynamic changes of sympathetic outflow were evaluated as the alterations of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) responses to certain chemicals. The results showed that the protein expressions of Ang II type 1 receptor (AT1R), calcitonin receptor-like receptor (CRLR) and receptor activity-modifying protein 2 (RAMP2) and RAMP3 were markedly increased, but IMD was much lower in OH rats when compared to control rats. IMD itself microinjection into PVN not only lowered SNA, NADPH oxidase activity and ROS level, but also decreased Ang II-caused sympathetic overdrive, and increased NADPH oxidase activity, ROS levels and mitogen-activated protein kinase/extracellular signal regulated kinase (MAPK/ERK) activation in OH rats. However, those effects were mostly blocked by the adrenomedullin (AM) receptor antagonist AM22-52 pretreatment. The enhancement of SNA caused by Ang II can be significantly attenuated by the pretreatment of AT1R antagonist lorsatan, superoxide scavenger Tempol and NADPH oxidase inhibitor apocynin (Apo) in OH rats. ERK activation inhibitor U0126 in the PVN reversed Ang II-induced enhancement of SNA, and Apo and IMD pretreatment in the PVN decreased Ang II-induced ERK activation. Chronic IMD administration in the PVN resulted in significant reductions in basal SNA and BP in OH rats. Moreover, IMD lowered NADPH oxidase activity and ROS level in the PVN; reduced the protein expressions of AT1R and NADPH oxidase subunits NOX2 and NOX4, and ERK activation in the PVN; and decreased Ang II levels-inducing sympathetic overactivation. These results indicated that IMD via AM receptors in the PVN attenuates SNA and hypertension, and decreases Ang II-induced enhancement of SNA through the inhibition of NADPH oxidase activity and ERK activation.