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Marked deficits in glucose availability, or glucoprivation, elicit organism-wide counter-regulatory responses whose purpose is to restore glucose homeostasis. However, while catecholamine neurons of the ventrolateral medulla (VLM CA ) are thought to orchestrate these responses, the circuit and cellular mechanisms underlying specific counter-regulatory responses are largely unknown. Here, we combined anatomical, imaging, optogenetic and behavioral approaches to interrogate the circuit mechanisms by which VLM CA neurons orchestrate glucoprivation-induced food seeking behavior. Using these approaches, we found that VLM CA neurons form functional connections with nucleus accumbens (NAc)-projecting neurons of the posterior portion of the paraventricular nucleus of the thalamus (pPVT). Importantly, optogenetic manipulations revealed that while activation of VLM CA projections to the pPVT was sufficient to elicit robust feeding behavior in well fed mice, inhibition of VLM CA -pPVT communication significantly impaired glucoprivation-induced feeding while leaving other major counterregulatory responses intact. Collectively our findings identify the VLM CA -pPVT-NAc pathway as a previously-neglected node selectively controlling glucoprivation-induced food seeking. Moreover, by identifying the ventrolateral medulla as a direct source of metabolic information to the midline thalamus, our results support a growing body of literature on the role of the PVT in homeostatic regulation.

The third isotype of beta-adrenoreceptors (β3-AR) has recently come (back) into focus after the observation of its expression in white and beige human adipocytes and its implication in metabolic regulation. This coincides with the recent development and marketing of agonists at the human receptor with superior specificity. Twenty years ago, however, we and others described the expression of β3-AR in human myocardium and its regulation of contractility and cardiac remodeling. Subsequent work from many laboratories has since expanded the characterization of β3-AR involvement in many aspects of cardiovascular physio(patho)logy, justifying the present effort to update current paradigms under the light of the most recent evidence.

For over 50 years, the sympathomimetic phenylpropanolamine (PPA; ±-norephedrine) was a primary active ingredient in over-the-counter nasal decongestants for both children and adults and continues to be prevalent in the vast majority of countries today. Previously, we reported that juvenile PPA exposure alters the developmental trajectory of catecholamine and amino acid neurotransmitter systems in the nucleus accumbens (NAC), impacting the motivational valence of cocaine in later life. The present study employed a combination of in vivo microdialysis and immunoblotting approaches to better understand how juvenile PPA exposure impacts catecholamine and glutamate function within the NAC. For this, C57BL/6J mice were pretreated repeatedly with PPA (0 or 40 mg/kg) during postnatal days 21-33. Starting at 70 days of age, the function and expression of receptors and transporters regulating extracellular dopamine and glutamate were determined. Juvenile PPA pretreatment completely abolished the capacity of selective dopamine and epinephrine reuptake inhibitors to increase NAC levels of both catecholamines, without impacting D2 or α2 receptor regulation of catecholamine release. Juvenile PPA pretreatment facilitated the rise in NAC glutamate elicited by dopamine, norepinephrine and glutamate transporter inhibitors and blunted mGlu2/3 inhibition of glutamate release in this region. These data confirm that juvenile exposure to PPA produces protracted perturbations in the regulation of extracellular catecholamine and glutamate levels within the NAC and further the hypothesis that early exposure to sympathomimetic drugs found in cough, cold and allergy medicines, have long-lasting effects upon neurotransmission within brain regions gating motivation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Activation of the sympathetic nervous system attenuates inflammation via catecholamines. Recent evidence has shown that electroacupuncture (EA) activates neuronal networks involved in the release of dopamine and norepinephrine that control systemic inflammation. In muscle, catecholamines are related to cyclic adenosine monophosphate (cAMP). This signaling molecule has been implicated in recovery from sustained contractile activity, which may induce muscular pain, such as that which occurs during low back pain (LBP)., Objective: Our aim was to evaluate the effects of EA used for the control of LBP on the activation of the sympathetic nervous system in a randomized controlled clinical trial in athletes., Methods: Two groups of athletes with acute or chronic low back pain were studied. EA, sham EA and pharmacological treatment (diclofenac sodium) were evaluated. The outcome measures included a pain score represented by a visual analogue scale (VAS) and serum levels of catecholamines quantified by enzyme-linked immunosorbent assay. In addition, blood was collected into chilled heparin tubes, placed in 96-well cell culture plates and incubated with an equal volume of Roswell Park Memorial Institute (RPMI) medium, with lipopolysaccharide (LPS) alone or with catecholamines. Tumor necrosis factor (TNF)-α levels in the supernatants were analyzed., Results: The results indicated that the initial pain ratings did not differ between the groups analyzed. EA induced epinephrine secretion but not norepinephrine or dopamine secretion. Although EA and pharmacological treatment did not differ in terms of pain relief, in vitro epinephrine and norepinephrine reduced TNF-α production in response to LPS stimuli., Conclusion: EA activates the sympathetic nervous system and induces the release of epinephrine, which could ameliorate inflammation and protect muscular tissue in addition to relieving pain.

The risk factors for severe COVID-19 are diverse, yet closely resemble the clinical manifestations of catecholamine excess states (eg, hypertension, cardiovascular disease, immune dysregulation, and hyperglycaemia), suggesting a potentially common basis for disease. Unfortunately, severe illness (eg, respiratory failure, compromised cardiac function, and shock) incurred by COVID-19 hinders the direct study of catecholamines in these patients, especially among those on multiple medications or those on adrenaline or noradrenaline infusions, or both. Phaeochromocytoma and paraganglioma (PPGL) are tumours that secrete catecholamines, namely adrenaline and noradrenaline, often in excess. PPGL are well studied disease processes in which the effects of catecholamines are easily discernible and therefore their potential biochemical and physiological influences in patients with COVID-19 can be explored. Because catecholamines are expected to have a role in patients with critical illness, patients on vasopressor infusions, and patients who sustain some acute and chronic physical stresses, the challenges involved in the management of catecholamine excess states are directly relevant to the treatment of patients with COVID-19. In this Personal View, we discuss the complex interplay between catecholamines and COVID-19, and the management of catecholamine excess states, while referencing relevant insights derived from the study of PPGL., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Hindbrain catecholamine (CA) neurons are essential for elicitation of protective counterregulatory responses (CRRs) to glucose deficit, including increased feeding and elevation of circulating corticosterone, epinephrine, and glucose. Severe or repeated antecedent glucoprivation results in attenuation of these CRRs and failure to correct glucose deficit, constituting a potentially lethal condition known as hypoglycemia-associated autonomic failure (HAAF) that may occur in patients with diabetes on insulin therapy. Recently, we demonstrated that selective pharmacogenetic activation of CA neuron subpopulations in the ventrolateral medulla during normoglycemia elicits these CRRs in a site-specific manner. In the present experiment, we examined the effect of repeated pharmacogenetic activation of CA neurons in the A1/C1 cell group on subsequent elicitation of feeding, corticosterone secretion, and respiratory quotient. We found that this prior treatment attenuated these responses to subsequent pharmacogenetic stimulation, similar to attenuation of these CRRs following repeated antecedent glucoprivation. This suggests that functional impairment of A1/C1 CA neurons resulting from antecedent glucoprivation may account, at least in part, for impairment of specific CRRs critical for restoration of normoglycemia in response to glucose deficit. Thus, a pharmacogenetic approach to selective activation of key neural circuits could provide a means of identifying neuropathogenic mechanisms contributing to HAAF., (© 2020 by the American Diabetes Association.)

Pheochromocytomas (PHEOs) are relatively rare catecholamine-producing tumors derived from adrenal medulla. Tumor microenvironment (TME) including neoangiogenesis has been explored in many human neoplasms but not necessarily in PHEOs. Therefore, in this study, we examined tumor infiltrating lymphocytes (CD4 and CD8), tumor associated macrophages (CD68 and CD163), sustentacular cells (S100p), and angiogenic markers (CD31 and areas of intratumoral hemorrhage) in 39 cases of PHEOs in the quantitative fashion. We then compared the results with pheochromocytoma of the adrenal gland scaled score (PASS), grading system for pheochromocytoma and paraganglioma (GAPP) and the status of intra-tumoral catecholamine-synthesizing enzymes (TH, DDC, and PNMT) as well as their clinicopathological factors. Intratumoral CD8 (p = 0.0256), CD31 (p = 0.0400), and PNMT (p = 0.0498) status was significantly higher in PHEOs with PASS <4 than PASS ≧4. In addition, intratumoral CD8 + lymphocytes were also significantly more abundant in well-than moderately differentiated PHEO according to GAPP score (p = 0.0108) and inversely correlated with tumor size (p = 0.0257). Intratumoral CD68 + cells were significantly higher in PHEOs with regular or normal histological patterns than those not (p = 0.0370) and inversely correlated with tumor size (p = 0.0457). The status of CD163 was significantly positively correlated with that of CD8 positive cells (p = 0.0032). The proportion of intratumoral hemorrhage areas was significantly higher in PHEOs with PASS ≧4 (p = 0.0172). DDC immunoreactivity in tumor cells was significantly positively correlated with PASS score (p = 0.0356) and TH status was significantly higher in PHEOs harboring normal histological patterns (p = 0.0236) and cellular monotony (p = 0.0219) than those not. Results of our present study did demonstrate that abundant CD8 + and CD68 + cells could represent a histologically low-scored tumor. In particular, PHEOs with increased intratumoral hemorrhage should be considered rather malignant. In addition, abnormal catecholamine-producing status of tumor cells such as deficient PNMT and TH and increased DDC could also represent more aggressive PHEOs., (Copyright © 2020 Gao, Yamazaki, Pecori, Tezuka, Ono, Omata, Morimoto, Nakamura, Satoh and Sasano.)

Astyanax mexicanus is a teleost fish that is in the process of allopatric speciation. Ancestral Astyanax are found in surface rivers and derived blind forms are found in cave systems. Adaptation to life in nutrient poor caves without predation includes the evolution of enhanced food seeking behaviors and loss of defensive responses. These behavioral adaptations may be mediated by changes in catecholaminergic control systems in the brain. We examined the distribution of tyrosine hydroxylase, a conserved precursor for the synthesis of the catecholamines dopamine and noradrenaline, in the brains of surface and cave Astyanax using immunohistochemistry. We found differences in tyrosine hydroxylase staining in regions that are associated with nonvisual sensory perception, motor control, endocrine release, and attention. These differences included significant increases in the diameters of tyrosine hydroxylase immunoreactive soma in cave Astyanax in the olfactory bulb, basal telencephalon, preoptic nuclei, ventral thalamus, posterior tuberculum, and locus coeruleus. These increases in modulation by dopamine and noradrenaline likely indicate changes in behavioral control that underlie adaptations to the cave environment., (© 2020 Wiley Periodicals, Inc.)

The present study aimed to evaluate osmotic pump-mediated controlled release of estrogen in males and androgen in females to analyze the impact on gonadotropin-releasing hormone (GnRH1), catecholamines (CAs) and other associated genes in the catfish, Clarias gariepinus. During pre-spawning phase, catfish were separately implanted osmotic pumps loaded with 17β-estradiol (E 2 ) in males and 17α-methyltestosterone (MT) in females at a dose of 10 μg/100 μl or saline (100 μl) controls into both sexes to release for 21 days and all fishes were maintained as per the duration. Further, GnRH1 expression levels were analysed in the discrete regions of brain after E 2 and MT treatments in male and female catfish, respectively using qPCR which revealed that GnRH1 expression was significantly higher in E 2 treated male as compared to the control. On the other hand, GnRH1 expression was lower in MT treated female when compared to the control in the discrete regions of brain. In addition, certain brain and monoaminergic system related genes showed a differential response. Catfish GnRH1 could be localized in preoptic area-hypothalamus (POA-HYP) that correlated with the expression profile in the discrete regions of catfish brain. Serum levels of sex steroids in the treated male fish indicated that the treatment of E 2 could maintain and impart feminization effect even in the presence of endogenous androgen during gonadal recrudescence while such an effect was not seen in females with androgen treatment. Measurement of CAs, L-3,4-dihydroxyphenylalanine, dopamine and norepinephrine levels in the male and female brain after the controlled release of E 2 and MT, respectively confirmed the modulation of neurotransmitters in the E 2 treated male than MT treated female fish. These results collectively suggest the severity of estrogenic over androgenic compounds to alter reproductive status even at a minimal dose by targeting CAs and GnRH1 at the level of brain of catfish. This study provides insights into the reproductive toxicity of sex steroid analogues at the level of brain GnRH1 and CA-ergic system in addition to serum T, 11-KT and E 2 levels during gonadal recrudescence, which is a crucial period of gametogenesis preceding spawning., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Metabolic effects of potassium (K) deficiency have been described for nearly 70 years but specific effects of low K availability on sugar composition, sugar export rate and its relationship with other leaf metabolites are not very well documented. Having such pieces of information is nevertheless essential to identify metabolic signatures to monitor K fertilization. This is particularly true in oil-producing crop species such as oil palm (Elaeis guineensis), which is strongly K-demanding and involves high sugar dependence for fruit formation because of low carbon use efficiency in lipid synthesis. Here, we used metabolic analyses, measured sugar export rates with 13 C isotopic labeling and examined the effects of K availability on both leaflet and rachis sugar metabolism in oil palm seedlings. We show that low K leads to a modification of sugar composition mostly in rachis and decreased sucrose and hexose export rates from leaflets. As a result, leaflets contained more starch and induced alternative pathways such as raffinose synthesis, although metabolites of the raffinose pathway remained quantitatively minor. The alteration of glycolysis by low K was compensated for by an increase in alternative sugar phosphate utilization by tyrosine metabolism, resulting in considerable amounts of tyramine and dopamine., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The claustrum (Cl) is a subcortical nucleus present in all mammalian species examined so far, whose function is still a puzzling problem. There is a wealth of data on its general anatomy, cytoarchitecture, and chemoarchitecture including the connectivity with both cortical and subcortical structures; instead, much less is known about the presence of the endocannabinoid system (ECs) an important neuromodulatory complex in this brain area. In an attempt to better understand the role of the ECs within the Cl circuitry, we undertook an immunohistochemical analysis to describe the distribution of the CB1 and of the endogenous cannabinoids degrading enzymes MGL and FAAH in the pig Cl as well as their relationship with both the catecholaminergic system and with parvalbumin (PV) expressing neurons. CB1, FAAH and MGL were expressed throughout the entire Cl. CB1 was expressed by fibers and puncta, while FAAH and MGL were mainly localized in the neuropil. FAAH also showed a faint cell body localization that colocalized with PV. Tyrosine hydroxylase positive fibers (catecholaminergic system), did not demonstrate the presence of CB1. Taken together, the results described herein provide evidence for an anatomical distribution of a CB1/PV signaling system in the pig Cl suggesting that PV cells may play a role within the ECs., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Measuring the dynamics of neurochemical-regulated immunity, particularly in the gut, has been a growing interest over the last several years because of its important implications in gastrointestinal inflammation, neurodegeneration, and even depression. Sympathetic noradrenergic nerves innervate the gastrointestinal tract and resident immune organs, including the mesenteric lymph nodes (MLN) and Peyer's patches. Previous research has suggested that neuronal inputs in the MLN release norepinephrine (NE) at neural-immune synapses to regulate immune function. The current immunological techniques do not have the appropriate temporal or spatial resolution to monitor this dynamic process in real-time, within specific regions of intact lymphoid organs. Monitoring dynamic neural signaling within intact immune organs, in real-time, would facilitate a deeper understanding of neuroimmune communication and would allow the mechanism of rapid immunomodulation to be elucidated. Here, we overcome this technological barrier by coupling real-time neurochemical detection using fast-scan cyclic voltammetry (FSCV) in live MLN slices from C57BL/6 mice. We have discovered rapid, spontaneous catecholamine transients in the T-cell zone of the MLN which are on the order of a few hundred nanomolar, rapid (a few seconds), and frequent (every 20-s). We demonstrate that the β 2 -adrenergic receptor and the classic catecholamine transporters (DAT and NET) play a minor role in transient regulation in the MLN suggesting that regulation at the neural-immune synapse is quite complicated and further mechanistic studies are needed. Overall, these findings provide direct evidence for rapid neurochemical events in the MLN which could have a major impact on our understanding of neurochemical-regulated immunomodulation in the gut., (© 2020 International Society for Neurochemistry.)

Current models emphasize that membrane voltage (Vm) depolarization-induced Ca 2+ influx triggers the fusion of vesicles to the plasma membrane. In sympathetic adrenal chromaffin cells, activation of a variety of G protein coupled receptors (GPCRs) can inhibit quantal size (QS) through the direct interaction of G protein Giβγ subunits with exocytosis fusion proteins. Here we report that, independently from Ca 2+ , Vm (action potential) per se regulates the amount of catecholamine released from each vesicle, the QS. The Vm regulation of QS was through ATP-activated GPCR-P2Y 12 receptors. D76 and D127 in P2Y 12 were the voltage-sensing sites. Finally, we revealed the relevance of the Vm dependence of QS for tuning autoinhibition and target cell functions. Together, membrane voltage per se increases the quantal size of dense-core vesicle release of catecholamine via Vm → P2Y 12 (D76/D127) → Giβγ → QS → myocyte contractility, offering a universal Vm-GPCR signaling pathway for its functions in the nervous system and other systems containing GPCRs., Competing Interests: The authors declare no competing interest.

An electroless deposition method is reported for the fabrication of gold nanoparticles (Au NPs) modified carbon nanopipette electrode (CNPE) for sensitive electrochemical detection of dopamine (DA) in aqueous solution and catecholamines released from PC12 cells. A CNPE is fabricated by chemical vapor deposition with a carbon layer onto nanocapillary and then contacted with copper (Cu) wire. Cu wire of CNPE is able to serve as reducing agent for electroless deposition of Au NPs on the CNPE because the potential of Cu 2+ /Cu is more negative than that of AuCl 4 - /Au. The method is simple, time-saving, and environmentally friendly. Field emission scanning electron microscopy, energy-dispersive X-ray analysis, and electrochemical techniques confirm the successful fabrication of the Au NPs/CNPE. Furthermore, Au NPs/CNPE exhibits a good sensing activity for DA oxidation with a wide linear determination range of 0.1-8 μmol/L and a low detection limit of 6 nmol/L. The Au NPs/CNPE can be potentially applied for measurement of catecholamines released from PC12 cells. This present work is believed to be beneficial to the design and development of active metal catalysts onto nanoelectrodes for the detection of electroactive biological molecules in living cells.Graphical abstract An electroless deposition method was developed for the fabrication of gold nanoparticles onto the carbon nanopipette electrode, which was served as an enhanced electrochemical sensing platform for highly sensitive detection of dopamine with a linear range of 0.1-8 μmol/L and a detection limit of 6 nmol/L, and was also applied in the detection of catecholamines released from PC12 cells.

Objective: Pure autonomic failure (PAF) is a rare disease characterized by neurogenic orthostatic hypotension (nOH), absence of signs of central neurodegeneration, and profound deficiency of the sympathetic neurotransmitter norepinephrine. Reports have disagreed about mechanisms of the noradrenergic lesion. Neuropathological studies have highlighted denervation, while functional studies have emphasized deficient vesicular sequestration of cytoplasmic catecholamines in extant neurons. We examined both aspects by a combined positron emission tomographic (PET) neuroimaging approach using 11 C-methylreboxetine ( 11 C-MRB), a selective ligand for the cell membrane norepinephrine transporter, to quantify interventricular septal myocardial noradrenergic innervation and using 18 F-dopamine ( 18 F-DA) to assess intraneuronal vesicular storage in the same subjects., Methods: Seven comprehensively tested PAF patients and 11 controls underwent 11 C-MRB PET scanning for 45 minutes (dynamic 5X1', 3X5', 1X10', static 15 minutes) and 18 F-DA scanning for 30 minutes (same dynamic imaging sequence) after 3-minute infusions of the tracers on separate days., Results: In the PAF group septal 11 C-MRB-derived radioactivity in the static frame was decreased by 26.7% from control (p = 0.012). After adjustment for nonspecific binding of 11 C-MRB, the PAF group had a 41.1% mean decrease in myocardial 11 C-MRB-derived radioactivity (p = 0.015). The PAF patients had five times faster postinfusion loss of 18 F-DA-derived radioactivity (70 ± 3% vs. 14 ± 8% by 30 minutes, p < 0.0001). At all time points after infusion of 18 F-DA and 11 C-MRB mean 18 F/ 11 C ratios in septal myocardium were lower in the PAF than control group., Interpretation: PAF entails moderately decreased cardiac sympathetic innervation and a substantial vesicular storage defect in residual nerves., (© 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.)

The domestic pig is commonly used as animal model in the pharmaceutical development of new therapeutics for treatment of diabetes. Since a formal definition of hypoglycaemia only exists in humans, the purpose of this study was to assess the counterregulatory response in the domestic pig at glucose levels known to induce symptoms of hypoglycaemia in humans. Six pigs were included in hyperinsulinaemic glucose clamps with plasma glucose targets of 2, 3 and 5 mmol/L in a cross-over design, and the associated glucose counterregulatory response was assessed by measuring glucose kinetics and levels of glucagon, c-peptide, catecholamines, cortisol and growth hormone. Results showed that the 2 and 3 vs 5 mmol/L clamps significantly decreased and increased the secretion of c-peptide and glucagon, respectively (P < .05). This finding was associated with increased rate of glucose appearance (R a ) and decreased rate of glucose disappearance (R d ) (P < .001). No marked differences in the catecholamine, growth hormone or cortisol response were observed. Consequently, like humans, pigs respond to hypoglycaemia by decreasing the pancreatic output of insulin while increasing that of glucagon, with increased glucose mobilization and decreased glucose disposal as a result. The hypoglycaemic clamps did not result in a marked secretion of the other counterregulatory hormones., (© 2020 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).)

Obesity is a health problem worldwide, and brown adipose tissue (BAT) is important for energy expenditure. Here, we explored the role of leukotriene A 4 hydrolase (LTA 4 H), a key enzyme in the synthesis of the lipid mediator leukotriene B 4 (LTB 4 ), in diet-induced obesity. LTA 4 H-deficient (LTA 4 H-KO) mice fed a high-fat diet (HFD) showed a lean phenotype, and bone-marrow transplantation studies revealed that LTA 4 H-deficiency in non-hematopoietic cells was responsible for this lean phenotype. LTA 4 H-KO mice exhibited greater energy expenditure, but similar food intake and fecal energy loss. LTA 4 H-KO BAT showed higher expression of thermogenesis-related genes. In addition, the plasma thyroid-stimulating hormone and thyroid hormone concentrations, as well as HFD-induced catecholamine secretion, were higher in LTA 4 H-KO mice. In contrast, LTB 4 receptor (BLT1)-deficient mice did not show a lean phenotype, implying that the phenotype of LTA 4 H-KO mice is independent of the LTB 4 /BLT1 axis. These results indicate that LTA 4 H mediates the diet-induced obesity by reducing catecholamine and thyroid hormone secretion., (© 2020 Federation of American Societies for Experimental Biology.)

In stressful situations, catecholamines modulate mammalian immune function, and in addition, they can be sensed by many bacteria. Catecholamine sensing was also found in the zoonotic gut pathogen Salmonella Typhimurium, probably contributing to the stress-induced increased risk of salmonellosis. Virulence traits such as proliferation and invasiveness are promoted upon bacterial catecholamine sensing, but it is unknown whether S. Typhimurium may also inhibit mammalian immune function in stressful situations. We thus investigated whether supernatants from S. Typhimurium grown in the presence of catecholamines modulate porcine mitogen-induced lymphocyte proliferation. Lymphocyte proliferation was reduced by supernatants from catecholamine-exposed Salmonella in a dose-dependent manner. We further examined whether adrenaline oxidation to adrenochrome, which is promoted by bacteria, could be responsible for the observed effect, but this molecule either enhanced lymphocyte functionality or had no effect. We could thereby exclude adrenochrome as a potential immunomodulating agent produced by S. Typhimurium. This study is the first to demonstrate that bacteria grown in the presence of catecholamine stress hormones alter their growth environment, probably by producing immunomodulating substances, in a way that host immune response is suppressed. These findings add a new dimension to interkingdom signaling and provide novel clues to explain the increased susceptibility of a stressed host to Salmonella infection., (Copyright © 2020 Reiske, Schmucker, Steuber, Toulouse, Pfaffinger and Stefanski.)

Parkinson's disease (PD) pathology is characterised by distinct types of cellular defects, notably associated with oxidative damage and mitochondria dysfunction, leading to the selective loss of dopaminergic neurons in the brain's substantia nigra pars compacta (SNpc). Exposure to some environmental toxicants and heavy metals has been associated with PD pathogenesis. Raised iron levels have also been consistently observed in the nigrostriatal pathway of PD cases. This study explored, for the first time, the effects of an exogenous environmental heavy metal (vanadium) and its interaction with iron, focusing on the subtoxic effects of these metals on PD-like oxidative stress phenotypes in Catecholaminergic a-differentiated (CAD) cells and PTEN-induced kinase 1 (PINK-1) B9 Drosophila melanogaster models of PD. We found that undifferentiated CAD cells were more susceptible to vanadium exposure than differentiated cells, and this susceptibility was modulated by iron. In PINK-1 flies, the exposure to chronic low doses of vanadium exacerbated the existing motor deficits, reduced survival, and increased the production of reactive oxygen species (ROS). Both Aloysia citrodora Paláu, a natural iron chelator, and Deferoxamine Mesylate (DFO), a synthetic iron chelator, significantly protected against the PD-like phenotypes in both models. These results favour the case for iron-chelation therapy as a viable option for the symptomatic treatment of PD.

Afferent lesions of the arterial baroreflex occur in familial dysautonomia. This leads to excessive blood pressure variability with falls and frequent surges that damage the organs. These hypertensive surges are the result of excess peripheral catecholamine release and have no adequate treatment. Carbidopa is a selective DOPA-decarboxylase inhibitor that suppresses catecholamines production outside the brain. To learn whether carbidopa can inhibit catecholamine-induced hypertensive surges in patients with severe afferent baroreflex failure, we conducted a double-blind randomized crossover trial in which patients with familial dysautonomia received high dose carbidopa (600 mg/day), low-dose carbidopa (300 mg/day), or matching placebo in 3 4-week treatment periods. Among the 22 patients enrolled (13 females/8 males), the median age was 26 (range, 12-59 years). At enrollment, patients had hypertensive peaks to 164/116 (range, 144/92 to 213/150 mm Hg). Twenty-four hour urinary norepinephrine excretion, a marker of peripheral catecholamine release, was significantly suppressed on both high dose and low dose carbidopa, compared with placebo ( P =0.0075). The 2 co-primary end points of the trial were met. The SD of systolic BP variability was reduced at both carbidopa doses (low dose: 17±4; high dose: 18±5 mm Hg) compared with placebo (23±7 mm Hg; P =0.0013), and there was a significant reduction in the systolic BP peaks on active treatment ( P =0.0015). High- and low-dose carbidopa were similarly effective and well tolerated. This study provides class Ib evidence that carbidopa can reduce blood pressure variability in patients with congenital afferent baroreflex failure. Similar beneficial effects are observed in patients with acquired baroreflex lesions.

Background: Evidence is accruing to suggest that microbiota-gut-brain signalling plays a regulatory role in cardiorespiratory physiology. Chronic intermittent hypoxia (CIH), modelling human sleep apnoea, affects gut microbiota composition and elicits cardiorespiratory morbidity. We investigated if treatment with prebiotics ameliorates cardiorespiratory dysfunction in CIH-exposed rats., Methods: Adult male rats were exposed to CIH (96 cycles/day, 6.0% O 2 at nadir) for 14 consecutive days with and without prebiotic supplementation (fructo- and galacto-oligosaccharides) beginning two weeks prior to gas exposures., Findings: CIH increased apnoea index and caused hypertension. CIH exposure had modest effects on the gut microbiota, decreasing the relative abundance of Lactobacilli species, but had no effect on microbial functional characteristics. Faecal short-chain fatty acid (SCFA) concentrations, plasma and brainstem pro-inflammatory cytokine concentrations and brainstem neurochemistry were unaffected by exposure to CIH. Prebiotic administration modulated gut microbiota composition and diversity, altering gut-metabolic (GMMs) and gut-brain (GBMs) modules and increased faecal acetic and propionic acid concentrations, but did not prevent adverse CIH-induced cardiorespiratory phenotypes., Interpretation: CIH-induced cardiorespiratory dysfunction is not dependant upon changes in microbial functional characteristics and decreased faecal SCFA concentrations. Prebiotic-related modulation of microbial function and resultant increases in faecal SCFAs were not sufficient to prevent CIH-induced apnoea and hypertension in our model. Our results do not exclude the potential for microbiota-gut-brain axis involvement in OSA-related cardiorespiratory morbidity, but they demonstrate that in a relatively mild model of CIH, sufficient to evoke classic cardiorespiratory dysfunction, such changes are not obligatory for the development of morbidity, but may become relevant in the elaboration and maintenance of cardiorespiratory morbidity with progressive disease., Funding: Department of Physiology and APC Microbiome Ireland, University College Cork, Ireland. APC Microbiome Ireland is funded by Science Foundation Ireland, through the Government's National Development Plan., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: In patients with cirrhosis, beta-adrenoceptors expressed on peripheral blood mononuclear cells have a reduced response to catecholamine stimulation. This study aimed to determine if chronic treatment with beta-blockers influences these changes., Methods: Blood samples were collected from patients with cirrhosis treated in outpatient clinics. Differences in cyclic AMP production before and after stimulation of mononuclear cells with epinephrine and/or N-Formylmethionine-leucyl-phenylalanine (fMLP) was used as a marker of beta-adrenoceptors activity in patients treated (N = 19) versus not treated (N = 55) with beta-blockers. In addition, we studied the gene expression of different types of adrenoceptors and possible associations with the activity of beta-adrenoceptors, the serum concentrations of catecholamines and cytokines, and the presence of bacterial antigens such as DNA or gram-negative bacterial endotoxin in patients' blood., Results: The increase in intracellular cAMP concentrations after stimulation of adrenergic receptors with epinephrine was significantly higher in samples from patients treated with beta-blockers. Older patients showed lower responses to epinephrine stimulus, while the response increased linearly with the duration of the beta-blocker treatment. mRNA expression levels of adrenoceptors β1, β2, β3 and α1-A, B and D showed no significant differences according to treatment with beta-blockers. Neither serum cytokines nor catecholamines levels were significantly associated with the intracellular production of cAMP after adrenergic stimulation., Conclusion: Chronic treatment with beta-blockers in patients with cirrhosis enables beta-adrenoceptors to respond to catecholamine stimulation irrespective of the degree of systemic adrenergic or immune activations of the patient at the time of sampling.

The changes in sympathetic innervations in lymphoid organs could be a key factor in immune dysregulation. The endocannabinoid system has been shown to exhibit potent immunomodulatory effects that may differ between males and females, representing a potential therapeutic target for peripheral and central inflammatory disorders. Thus, in the present study, an examination was made of the effect of fatty acid amide hydrolase inhibitor URB597 treatment on splenic catecholamine content, synthesis, uptake and degradation in chronically unpredictably stressed (CUS) female and male rats. The results show that CUS increases anxiety-like behaviors and that URB597 had an anxiolytic effect on chronically stressed animals of both sexes. CUS induced the expression of plasma interleukin - 6 (IL-6), interleukin - 10 (IL-10) and IL-6 in the spleen, whereas the expression of IL-10 was reduced in the spleen of both sexes. URB597 treatment did not cause changes in IL-6 in plasma or the spleen, whereas it increased IL-10 in the spleen in CUS animals of both sexes. CUS caused a significant depletion of noradrenaline content in the spleen of female rats and a reduction in noradrenaline uptake in the spleen of female rats, while stressed males had a small but insignificant decrease of splenic noradrenaline levels and an enhanced uptake. The FAAH inhibitor URB597 enhances reduced noradrenaline content, affecting its uptake directly at the level of the spleen. It gives rise to the possibility that endocannabinoids exert a neurorestorative effect on the sympathetic nerve system and cell-mediated immune responses in the spleen of chronically stressed rats., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Although chronic stress is an important risk factor for cardiovascular diseases (CVD) onset, the underlying mechanisms driving such pathophysiological complications remain relatively unknown. Here, dysregulation of innate stress response systems and the effects of downstream mediators are strongly implicated, with the vascular endothelium emerging as a primary target of excessive glucocorticoid and catecholamine action. Therefore, this review article explores the development of stress-related endothelial dysfunction by focusing on the following: 1 ) assessing the phenomenon of stress and complexities surrounding this notion, 2 ) discussing mechanistic links between chronic stress and endothelial dysfunction, and 3 ) evaluating the utility of various preclinical models currently employed to study mechanisms underlying the onset of stress-mediated complications such as endothelial dysfunction. The data reveal that preclinical models play an important role in our efforts to gain an increased understanding of mechanisms underlying stress-mediated endothelial dysfunction. It is our understanding that this provides a good foundation going forward, and we propose that further efforts should be made to 1 ) more clearly define the concept of stress and 2 ) standardize protocols of animal models with specific guidelines to better indicate the mental complications that are simulated.

Diversity among highly specialized cells underlies the fundamental biology of complex multi-cellular organisms. One of the essential scientific questions in cardiac biology has been to define subpopulations within the heart. The heart parenchyma comprises specialized cardiomyocytes (CMs). CMs have been canonically classified into a few phenotypically diverse subpopulations largely based on their function and anatomic localization. However, there is growing evidence that CM subpopulations are in fact numerous, with a diversity of genetic origin and putatively different roles in physiology and pathophysiology. In this chapter, we introduce a recently discovered CM subpopulation: phenylethanolamine- N -methyl transferase (Pnmt)-derived cardiomyocytes (PdCMs). We discuss: (i) canonical classifications of CM subpopulations; (ii) discovery of PdCMs; (iii) Pnmt and the role of catecholamines in the heart; similarities and dissimilarities of PdCMs and canonical CMs; and (iv) putative functions of PdCMs in both physiological and pathological states and future directions, such as in intra-cardiac adrenergic signalling.

Cardiomyopathies are myocardial disorders in which heart muscle is structurally and/or functionally abnormal. Previously, structural cardiomyocyte disorders due to adrenal diseases, such as hyperaldosteronism, hypercortisolism, and hypercatecholaminism, were misunderstood, and endomyocardial biopsy (EMB) was not performed because was considered dangerous and too invasive. Recent data confirm that, if performed in experienced centers, EMB is a safe technique and gives precious information about physiopathological processes implied in clinical abnormalities in patients with different systemic disturbances. In this review, we illustrate the most important features in patients affected by primary aldosteronism (PA), Cushing's syndrome (CS), and pheochromocytoma (PHEO). Then, we critically describe microscopic and ultrastructural aspects that have emerged from the newest EMB studies. In PA, the autonomous hypersecretion of aldosterone induces the alteration of ion and water homeostasis, intracellular vacuolization, and swelling; interstitial oedema could be a peculiar feature of myocardial toxicity. In CS, cardiomyocyte hypertrophy and myofibrillolysis could be related to higher expression of atrogin-1. Finally, in PHEO, the hypercontraction of myofilaments with the formation of contraction bands and occasional cellular necrosis has been observed. We expect to clear the role of EMB in patients with cardiomyopathies and adrenal disease, and we believe EMB is a valid tool to implement new management and therapies.

We investigated the antidepressant effect of creatine (CRE) and taurine (TAU) mixtures on behavioural changes and biomarkers in stress-induced depression in Drosophila melanogaster and a mouse model. Following CRE/TAU mixture administration in the Drosophila model, depression-like state induced by vibration, locomotion, climbing activity, and survival rate were measured. The normal stress (NS) group demonstrated decreased movement than the control (CON) group; movements in the CRE/TAU-treated group (particularly 0.15/0.5%) returned to the CON levels. Antidepressant effects of CRE/TAU mixtures were confirmed in a depressive mouse model induced by chronic mild stress. In behavioural assessments, movement and sucrose preference of the CRE/TAU group increased to a similar level as in the positive control group; hippocampal catecholamine and serotonin levels increased significantly. Stress-related hormones (adrenocorticotropic and corticotropin-releasing hormones) and inflammatory factors (IL-1β, IL-6, and TNF-α) increased in the NS group but significantly decreased in the CRE/TAU-treated group. Brain signalling protein expression ratio of phosphorylated protein kinase B (p-Akt)/Akt, phosphorylated extracellular signal-regulated kinase (p-ERK)/ERK, and brain-derived neurotrophic factor (BDNF) significantly increased in the CRE/TAU-treated group. These results indicate that CRE/TAU-induced antidepressant effects are associated with increased behavioural patterns and downregulation of stress hormones and cytokines, mediated through Akt and ERK/BDNF pathways in vertebrate models.

Introduction: The effect of renal sympathetic denervation (RDN) on neurohormonal responses is largely unknown. We aimed to assess the effect of RDN on the renin-angiotensin-aldosterone system (RAAS) and endogenous catecholamines., Methods: A total of 60 patients with hypertension underwent RDN and remained on a stable antihypertensive drug regimen. Samples for plasma aldosterone, plasma renin and urine (nor)metanephrine were collected at baseline and at 6 months post procedure. Ambulatory blood pressure (BP) recordings were obtained at baseline and at 6 months post procedure., Results: Mean age was 64±9 years, and 30/60 patients were male. At 6 months, average daytime systolic and diastolic ambulatory BP decreased by 10 and 6 mmHg, respectively ( p <0.001). No significant change was observed in plasma aldosterone (median=248.0 pmol/L (interquartile range (IQR) 113.3-369.5 pmol/L) vs. median=233.0 pmol/L (IQR 110.3-360.8 pmol/L); p =0.66); renin (median=19.5 µIU/mL (IQR 6.8-119.5 µIU/mL) vs. median=14.3 µIU/mL (IQR 7.2-58.0 µIU/mL); p =0.32), urine metanephrine (median=0.46 µmol/L (IQR 0.24-0.77 µmol/L) vs. median=0.46 µmol/L (IQR 0.22-0.88 µmol/L); p =0.75) and normetanephrine (median=1.41 µmol/L (IQR 0.93-2.00 µmol/L vs. median =1.56 (IQR 0.74-2.50 µmol/L); p =0.58) between baseline and 6 months, respectively. No correlation was found between the decrease in mean systolic daytime BP and changes in RAAS hormones or endogenous catecholamines., Conclusion: Despite significant reductions in ambulatory BP, RDN did not result in a significant change in endogenous catecholamines or in RAAS hormones at 6 months.

We studied histophysiology of the adrenal medulla in adult (70-day-old) male Wistar rats developmentally exposed to low doses of endocrine disruptor DDT. It was found that exposure to DDT during the prenatal and postnatal ontogeny decelerated the development of the adrenal medulla and reduced the synthesis of tyrosine hydroxylase, the rate-liming enzyme of catecholamine synthesis, in chromaffin cells, which led to a decrease in epinephrine secretion into the blood.

DJ-1 protein deficiency caused by PARK7 gene mutation has been suggested to closely relate to Parkinson's disease (PD), mainly through the attenuation D2 dopamine receptor activity in mice; however, whether or how it affects the vesicular storage and exocytosis of neurochemicals remains unclear. By using electrochemical methods at a single vesicle/cell level with nano/micro-tip electrodes, we for the first time find that DJ-1 protein deficiency caused by PARK7 gene knockout (KO) in mice has little effect on vesicular catecholamine content but significantly prolongs the exocytotic events, especially the closing time of exocytotic fusion pores. Further studies suggest the inhibition of α-synuclein aggregation by DJ-1 protein might be one way that DJ-1 protein acts on neurotransmission. This finding offers the first direct link between DJ-1 protein deficiency and vesicular chemical storage and release of chemicals, providing a new chemical insight into the pathology of PD caused by PARK7 gene mutation., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors. The clinical presentation of pediatric PPGLs is highly variable. In cases with pheochromocytoma (PCC), excess catecholamine may stimulate myocytes and cause structural changes, leading to life-threatening complications ranging from stress cardiomyopathy (CM) to dilated CM. Herein, we report the case of catecholamine-induced myocarditis in a child with asymptomatic PCC. A 12-year-and-2-month-old male patient with a known diagnosis of type-1 neurofibromatosis was brought to the emergency department due to palpitations and vomiting. On physical examination, arterial blood pressure was 113/81 mmHg, pulse was 125/min, and body temperature was 36.5 °C. Laboratory tests showed a leucocyte count of 12.8x10 3 μL/L and a serum C-reactive protein level of 1.1 mg/dL (Normal range: 0-0.5). Thyroid function tests were normal, while cardiac enzymes were elevated. Electrocardiogram revealed no pathological findings other than sinus tachycardia. The patient was diagnosed with and treated for myocarditis as echocardiography revealed a left ventricular ejection fraction of 48%. Viral and bacterial agents that may cause myocarditis were excluded via serological tests and blood cultures. Blood pressure, normal at the time of admission, was elevated (140/90 mmHg) on the 5 th day of hospitalization. Magnetic resonance imaging revealed a 41x46x45 mm solid adrenal mass. The diagnosis of PCC was confirmed by elevated urinary and plasma metanephrines. The patient underwent surgery. Histopathology of the excised mass was compatible with PCC. It should be kept in mind that, even if there are no signs and symptoms of catecholamine elevation, CM may be the first sign of PCC.

Aims/hypothesis: Treatment with the α3β4 nicotinic acetylcholine receptor (nAChR) agonist, 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP), improves glucose tolerance in diet-induced obese (DIO) mice, but the physiological and molecular mechanisms are unknown., Methods: DMPP (10 mg/kg body weight, s.c.) was administered either in a single injection (acute) or daily for up to 14 days (chronic) in DIO wild-type (WT) and Chrnb4 knockout (KO) mice and glucose tolerance, tissue-specific tracer-based glucose metabolism, and insulin signalling were assessed., Results: In WT mice, but not in Chrnb4 KO mice, single acute treatment with DMPP induced transient hyperglycaemia, which was accompanied by high plasma adrenaline (epinephrine) levels, upregulated hepatic gluconeogenic genes, and decreased hepatic glycogen content. In contrast to these acute effects, chronic DMPP treatment in WT mice elicited improvements in glucose tolerance already evident after three consecutive days of DMPP treatment. After seven days of DMPP treatment, glucose tolerance was markedly improved, also in comparison with mice that were pair-fed to DMPP-treated mice. The glycaemic benefit of chronic DMPP was absent in Chrnb4 KO mice. Chronic DMPP increased insulin-stimulated glucose clearance into brown adipose tissue (+69%), heart (+93%), gastrocnemius muscle (+74%) and quadriceps muscle (+59%), with no effect in white adipose tissues. After chronic DMPP treatment, plasma adrenaline levels did not increase following an injection with DMPP. In glucose-stimulated skeletal muscle, we detected a decreased phosphorylation of the inhibitory Ser640 phosphorylation site on glycogen synthase and a congruent increase in glycogen accumulation following chronic DMPP treatment., Conclusions/interpretation: Our data suggest that DMPP acutely induces adrenaline release and hepatic glycogenolysis, while chronic DMPP-mediated activation of β4-containing nAChRs improves peripheral insulin sensitivity independently of changes in body weight via mechanisms that could involve increased non-oxidative glucose disposal into skeletal muscle.

Renalase is predominantly expressed in the kidney, where it plays a role in catecholamine metabolism and blood pressure regulation. Moderate-intensity exercise (MEX) has been shown to increase the concentration of renalase in the blood and to reduce renal function in humans. Moreover, such exercise was also reported to increase catecholamine levels. Here, we examined renalase concentration in the blood and renalase expression levels in different organs after MEX in rats. Twelve male Wistar rats were made to run on a treadmill (MEX group) for 60 min at 20 m·min -1 , after resting for 15 min. The control group rats were euthanized after resting on the treadmill. Tissue and blood samples were analyzed using western blotting, real-time RT-PCR and ELISA. Overall, the concentrations of renalase in the blood were significantly higher in the MEX group than that in the control group. Renalase expression was decreased in the kidney after 60 min of exercise, whereas the expression of renalase mRNA and protein in the extensor digitorum longus and plantaris muscles, respectively, increased after exercise. However, the expression of renalase in the other tissues examined did not change after acute exercise. In conclusion, we report that MEX for 60 min increases both renalase concentration in the blood and its expression in skeletal muscle., (© 2020 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

The erythropoietin-producing human hepatocellular receptor EPH receptor B6 (EPHB6) is a receptor tyrosine kinase that has been shown previously to control catecholamine synthesis in the adrenal gland chromaffin cells (AGCCs) in a testosterone-dependent fashion. EPHB6 also has a role in regulating blood pressure, but several facets of this regulation remain unclear. Using amperometry recordings, we now found that catecholamine secretion by AGCCs is compromised in the absence of EPHB6. AGCCs from male knockout (KO) mice displayed reduced cortical F-actin disassembly, accompanied by decreased catecholamine secretion through exocytosis. This phenotype was not observed in AGCCs from female KO mice, suggesting that testosterone, but not estrogen, contributes to this phenotype. Of note, reverse signaling from EPHB6 to ephrin B1 (EFNB1) and a 7-amino acid-long segment in the EFNB1 intracellular tail were essential for the regulation of catecholamine secretion. Further downstream, the Ras homolog family member A (RHOA) and FYN proto-oncogene Src family tyrosine kinase (FYN)-proto-oncogene c-ABL-microtubule-associated monooxygenase calponin and LIM domain containing 1 (MICAL-1) pathways mediated the signaling from EFNB1 to the defective F-actin disassembly. We discuss the implications of EPHB6's effect on catecholamine exocytosis and secretion for blood pressure regulation., Competing Interests: Conflict of interest—The authors declare that they have no conflicts of interest with the contents of this article., (© 2020 Shi et al.)

Nitric oxide (NO)-mediated production of cyclic guanosine 3',5'-monophosphate (cGMP) is a crucial signaling pathway that controls a wide array of neuronal functions, including exocytotic neurotransmitter release. A novel nitrated derivative of cGMP, 8-nitro-cGMP, not only activates cGMP-dependent protein kinase (PKG), but also has membrane permeability and redox activity to produce superoxide and S-guanylated protein. To date, no studies have addressed the effects of 8-nitro-cGMP on exocytotic kinetics. Here, we aimed to assess the 8-nitro-cGMP-mediated modulation of the depolarization-evoked catecholamine release from bovine chromaffin cells. 8-Nitro-cGMP was produced in bovine chromaffin cells dependent on NO donor. Amperometric analysis revealed that 8-nitro-cGMP modulated the kinetic parameters of secretory spikes from chromaffin cells, particularly decreased the speed of individual spikes, resulting in a reduced amperometric spike height, slope β, and absolute value of slope γ. The modulatory effects were independent of the PKG signal and superoxide production. This is the first study to demonstrate that 8-nitro-cGMP modulates exocytosis and provide insights into a novel regulatory mechanism of exocytosis., Competing Interests: Declaration of competing interest The authors declare to no competing financial interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Recently, magnetic nanoparticles (MNPs) have gained much attention in the field of biomedical engineering for therapeutic as well as diagnostic purposes. Carbon magnetic nanoparticles (C-MNPs) are a class of MNPs categorized as organic nanoparticles. C-MNPs have been under considerable interest in studying in various applications such as magnetic resonance imaging, photothermal therapy, and intracellular transportof drugs. Research work is still largely in progress for testing the efficacy of C-MNPs on the theranostics platform in cellular studies and animal models. In this study, we evaluated the neurobehavioral toxicity parameters on the adult zebrafish ( Danio rerio ) at either low (1 ppm) or high (10 ppm) concentration level of C-MNPs over a period of two weeks by waterborne exposure. The physical properties of the synthesized C-MNPs were characterized by transmission electron microscopy, Raman, and XRD spectrum characterization. Multiple behavior tests for the novel tank, mirror biting, predator avoidance, conspecific social interaction, shoaling, and analysis of biochemical markers were also conducted to elucidate the corresponding mechanism. Our data demonstrate the waterborne exposure of C-MNPs is less toxic than the uncoated MNPs since neither low nor high concentration C-MNPs elicit toxicity response in behavioral and biochemical tests in adult zebrafish. The approach combining biochemical and neurobehavioral approaches would be helpful for understanding C-MNPs association affecting the bioavailability, biosafety, interaction, and uptake of these C-MNPs in the living organism.

Dexmedetomidine (DEX) is a highly selective α 2 adrenergic receptor ( α 2AR) agonist currently used in clinical settings. Because DEX has dose-dependent advantages of sedation, analgesia, antianxiety, inhibition of sympathetic nervous system activity, cardiovascular stabilization, and significant reduction of postoperative delirium and agitation, but does not produce respiratory depression and agitation, it is widely used in clinical anesthesia and ICU departments. In recent years, much clinical study and basic research has confirmed that DEX has a protective effect on a variety of organs, including the nervous system, heart, lungs, kidneys, liver, and small intestine. It acts by reducing the inflammatory response in these organs, activating antiapoptotic signaling pathways which protect cells from damage. Therefore, based on wide clinical application and safety, DEX may become a promising clinical multiorgan protection drug in the future. In this article, we review the physiological effects related to organ protection in α 2AR agonists along with the organ-protective effects and mechanisms of DEX to understand their combined application value., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2020 Naren Bao and Bing Tang.)

The full consensus on the role of dietary polyphenols as human-health-promoting compounds remains elusive. The two-way interaction between polyphenols and gut microbiota (GM) (i.e., modulation of GM by polyphenols and their catabolism by the GM) is determinant in polyphenols' effects. The identification of human metabotypes associated with a differential gut microbial metabolism of polyphenols has opened new research scenarios to explain the inter-individual variability upon polyphenols consumption. The metabotypes unequivocally identified so far are those involved in the metabolism of isoflavones (equol and(or) O-desmethylangolesin producers versus non-producers) and ellagic acid (urolithin metabotypes, including producers of only urolithin-A (UM-A), producers of urolithin-A, isourolithin-A, and urolithin-B (UM-B), and non-producers (UM-0)). In addition, the microbial metabolites (phenolic-derived postbiotics) such as equol, urolithins, valerolactones, enterolactone, and enterodiol, and 8-prenylnaringenin, among others, can exert differential health effects. The knowledge is updated and position is taken here on i) the two-way interaction between GM and polyphenols, ii) the evidence between phenolic-derived postbiotics and health, iii) the role of metabotypes as biomarkers of GM and the clustering of individuals depending on their metabotypes (metabotyping) to explain polyphenols' effects, and iv) the gut microbial metabolism of catecholamines to illustrate the intersection between personalized nutrition and precision medicine., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Growing evidence has demonstrated that adipose-derived stem cell-derived extracellular vesicles enhance the survival of fat grafts and the browning of white adipose tissue. We evaluated whether supplementation with adipose-derived stem cell-derived extracellular vesicles promotes the survival and browning of fat grafts., Methods: Extracellular vesicles derived from adipose-derived stem cells were injected into fat grafts of C57BL/6 mice once per week until postgraft week 12. The grafts were collected and weighed after postgraft weeks 2, 4, and 12. The histological morphology, neovascularization, and the proportion of M2 macrophages of grafts were evaluated. The ability of extracellular vesicles to promote macrophage polarization and catecholamine secretion was detected. Whether the inducement of browning adipose differentiation is extracellular vesicles or the paracrine effect of M2 macrophages polarized by extracellular vesicles was also verified., Results: Grafts treated by extracellular vesicles derived from adipose-derived stem cells showed enhanced beige adipose regeneration with increased neovascularization, M2 macrophage proportion, and norepinephrine secretion at postgraft week 4. Increased retention and decreased fibrosis and necrosis were noted at postgraft week 12. The extracellular vesicles uptake by macrophages promoted M2 type polarization and catecholamine secretion while suppressing M1 type polarization. Of note, browning adipose differentiation with enhanced energy expenditure could be promoted only by the conditioned medium from extracellular vesicle-polarized M2 macrophages but not by extracellular vesicles themselves., Conclusions: Supplementation with extracellular vesicles derived from adipose-derived stem cells increases fat graft survival and browning by which extracellular vesicles-polarized M2 macrophages secrete catecholamines to promote beige adipose regeneration.

Aims/hypothesis: The aim of this study was to determine the mechanism(s) for hypoglycaemia occurring late following oral glucose loading in patients with cystic fibrosis (CF)., Methods: A 3 h 75 g OGTT was performed in 27 non-diabetic adults with CF who were classified based on this test as experiencing hypoglycaemia (glucose <3.3 mmol/l with or without symptoms or glucose <3.9 mmol/l with symptoms, n = 14) or not (n = 13). Beta cell function, incretin (glucagon-like peptide-1 [GLP-1] and glucose-dependent insulinotropic peptide [GIP]) and counterregulatory hormone responses (glucagon, catecholamines, growth hormone and cortisol) were assessed., Results: The two groups did not differ in age, weight or BMI. There were more male participants and individuals with pancreatic exocrine insufficiency in the hypoglycaemia group. Fasting plasma glucose did not differ between the two groups (5.3 ± 0.16 vs 5.3 ± 0.10 mmol/l). Both fasting insulin (20.7 ± 2.9 vs 36.5 ± 4.8 pmol/l; p = 0.009) and C-peptide (0.38 ± 0.03 vs 0.56 ± 0.05 nmol/l; p = 0.002) were lower in those who experienced hypoglycaemia. Following glucose ingestion, glucose concentrations were significantly lower in the hypoglycaemia group from 135 min onwards, with a nadir of 3.2 ± 0.2 vs 4.8 ± 0.3 mmol/l at 180 min (p < 0.001). The test was terminated early in three participants because of a glucose level <2.5 mmol/l. Insulin and C-peptide concentrations were also lower in the hypoglycaemia group, while incretin hormone responses were not different. Modelling demonstrated that those experiencing hypoglycaemia were more insulin sensitive (439 ± 17.3 vs 398 ± 13.1 ml min -1  m -2 , p = 0.074 based on values until 120 min [n = 14]; 512 ± 18.9 vs 438 ± 15.5 ml min -1  m -2 , p = 0.006 based on values until 180 min [n = 11]). In line with their better insulin sensitivity, those experiencing hypoglycaemia had lower insulin secretion rates (ISR fasting : 50.8 ± 3.2 vs 74.0 ± 5.9 pmol min -1  m -2 , p = 0.002; ISR OGTT : 44.9 ± 5.0 vs 63.4 ± 5.2 nmol/m 2 , p = 0.018) and beta cell glucose sensitivity (47.4 ± 4.5 vs 79.2 ± 7.5 pmol min -1  m -2 [mmol/l] -1 , p = 0.001). Despite the difference in glucose concentrations, there were no significant increases in glucagon, noradrenaline, cortisol or growth hormone levels. Adrenaline increased by only 66% and 61% above baseline at 165 and 180 min when glucose concentrations were 3.8 ± 0.2 and 3.2 ± 0.2 mmol/l, respectively., Conclusions/interpretation: Hypoglycaemia occurring late during an OGTT in people with CF was not associated with the expected counterregulatory hormone response, which may be a consequence of more advanced pancreatic dysfunction/destruction.

Neuropeptide Y (NPY) controls energy homeostasis including orexigenic actions in mammalians and non-mammalians. Recently, NPY has attracted attention as a mediator of emotional behaviour and psychosomatic diseases. However, its functions are not fully understood. We established npy gene-deficient (NPY-KO) zebrafish (Danio rerio) to assess the relationship between NPY and emotional behaviours. The NPY-KO zebrafish exhibited similar growth, but pomc and avp mRNA levels in the brain were higher as compared to wild-type fish. NPY-KO zebrafish exhibited several anxiety-like behaviours, such as a decrease in social interaction in mirror test and decreased locomotion in black-white test. The acute cold stress-treated NPY-KO zebrafish exhibited anxiety-like behaviours such as remaining stationary and swimming along the side of the tank in the mirror test. Moreover, expression levels of anxiety-associated genes (orx and cck) and catecholamine production (gr, mr, th1 and th2) were significantly higher in NPY-KO zebrafish than in wild-type fish. We demonstrated that NPY-KO zebrafish have an anxiety phenotype and a stress-vulnerability like NPY-KO mice, whereby orx and/or catecholamine signalling may be involved in the mechanism actions.

Recent advances in sample preparation protocols and instrumentation allow current imaging mass spectrometry (IMS) to enable the visualization of small molecule tissue localization, including that of monoamine neurotransmitters, such as serotonin, dopamine, and norepinephrine. Although monoamine-producing neurons, and their projections and synaptic connections, have been thoroughly characterized, in situ monoamine localization within these circuits remains unclear. Moreover, studying the fluctuations in local monoamine concentration in response to physiological stimuli, drug administration, and neurodegenerative disease progression is worthwhile, and can be achieved by analyzing the in situ concentration maps afforded by coupling IMS with on-tissue derivatization protocols. Recent reports have shown that monoamines localize within cell bodies and also translocate to distant nerve terminals, indicating active transport along axons and/or local synthesis at the terminals. Moreover, IMS can reveal regionally segregated monoamine fluctuations, such as rapid dopamine fluctuation within the nucleus accumbens (NAc) subregion during pain sensation. Furthermore, since exogenous drug pharmacokinetics can also be visualized by IMS, this technique could provide powerful methodologies enabling the simultaneous imaging of monoamines and drugs that selectively regulate monoamine signaling, such as serotonin reuptake inhibitors (SSRIs). Therefore, IMS could reveal where SSRIs administered over the long-term accumulate and how they affect local monoamine metabolism., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2020. Published by Elsevier Inc.)

Besides a fundamental structural role at the plasma membrane, spectrin- and actin-based skeletons have been proposed to participate in various processes including vesicular trafficking. Neuroendocrine cells release hormones and neuropeptides through calcium-regulated exocytosis, a process that is coordinated by a fine remodeling of the actin cytoskeleton. We describe here that calcium-regulated exocytosis is impaired in chromaffin and PC12 cells with reduced αII-spectrin expression levels. Using yeast two-hybrid screening, we show that neuronal Wiskott-Aldrich Syndrome protein (N-WASP) is a partner of the αII-spectrin SH3 domain and demonstrate that secretagogue-evoked N-WASP recruitment at cell periphery is blocked in the absence of αII-spectrin. Additionally, experiments performed with ectopically expressed αII-spectrin mutant unable to bind N-WASP indicated that the interaction between SH3 domain and N-WASP is pivotal for neuroendocrine secretion. Our results extend the list of spectrin interactors and strengthen the idea that αII-spectrin is an important scaffold protein that gathers crucial actin-related players of the exocytic machinery., (© 2019 International Union of Biochemistry and Molecular Biology.)

The influence of pesticides on the metabolism of edible plants has not been fully investigated. Moreover, once introduced into the environment, pesticides are degraded to many compounds with undefined bioactivity. In presented work, under experimental conditions, model edible plant (Raphanus sativus var. longipinnatus) was exposed to herbicide stress by application of a herbicide (mesotrione, 2-(4-methanesulfonyl-2-nitrobenzoyl)cyclohexane-1,3-dione, MES) or its degradation products (amino-4-(methylsulfonyl)benzoic acid, AMBA; 4-(methylsulfonyl)-2-nitrobenzoic acid MNBA; cyclohexane-1,3-dione, CHD). Metabolic profiles of plants were employed to estimate the plant's defence response to MES and its metabolites. The intensity of herbicide stress was determined by measuring the changes in chlorophyll and catecholamines concentration formed in the shikimic acid pathway. Non-target analysis was conducted by LC-MS/MS, determination of catecholamines by LC-FL, chlorophyll by spectrophotometry. The highest phytotoxicity is characterized by MES (2000%-fold increase in the content of herbicide stress marker (normetanephrine) compared to a blank), followed by CHD (500%) combined with 15% increase in chlorophyll concentration. AMBA and MNBA as stress factors caused the increase in the content of catecholamines in the plant (86-160%). Simultaneously, an increase in chlorophyll content was observed (26-50%). Such diversity of the organism's defence response, also visible on metabolic profiles, can be associated with the chemical structure of compounds that are stress factors. MES and CHD, in contrast to AMBA and MNBA, have cyclohexano-1,3-moiety in their structure, which seems to be responsible for herbicidal properties., Competing Interests: Declaration of competing interest Authors declare no conflict of interest. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pheochromocytoma crisis is a rare and possibly fatal emergency. Hypersecreted catecholamines may result in myocardial injury via its direct toxic effect on cardiomyocytes or mediating vasoconstriction which will reduce coronary blood flow in this special setting. Interestingly, several case studies have reported the occurrence of ST-segment elevation myocardial infarction in patients with pheochromocytoma crisis. However, no one found the angiographic evidence of occlusive thrombus in the infarct-related coronary artery. Additionally, pheochromocytoma can induce hypercoagulability and promote thrombosis, but spontaneous coronary thrombosis has never been reported in this condition. Here, we report an unusual case of pheochromocytoma crisis presenting with STEMI due to spontaneous coronary thrombosis., (Copyright © 2020 Chen, Zheng, Li, Peng and Chen.)

Despite ongoing research efforts, mechanisms of brain aging are still enigmatic and need to be elucidated for a better understanding of age-associated cognitive decline. The aim of this study is to investigate aging in the prefrontal cortex region of human brain in a meta-analysis of transcriptome datasets. We analyzed 591 gene expression datasets pertaining to female and male human prefrontal cortex biopsies of distinct ages. We used hierarchical clustering and principal component analysis (PCA) to determine the influence of sex and age on global transcriptome levels. In sex-specific analysis we identified genes correlating with age and differentially expressed between groups of young, middle-aged and aged. Pathways and gene ontologies (GOs) over-represented in the resulting gene sets were calculated. Potential causal relationships between genes and between GOs were explored employing the Granger test of gene expression time series over the range of ages. The most outstanding results were the age-related decline of synaptic transmission and activated expression of glial fibrillary acidic protein (GFAP) in both sexes. We found an antagonistic relationship between calcium/calmodulin dependent protein kinase IV (CAMK4) and GFAP which may include regulatory mechanisms involving cAMP responsive element binding protein (CREB) and mitogen-activated protein kinase (MAPK, alias ERK). Common to both sexes was a decline in synaptic transmission, neurogenesis and an increased base-level of inflammatory and immune-related processes. Furthermore, we detected differences in dendritic spine morphogenesis, catecholamine signaling and cellular responses to external stimuli, particularly to metal (Zinc and cadmium) ions which were higher in female brains.

Tyramine (TA), a biogenic monoamine, plays various important physiological roles including immunological regulation in invertebrates. In this study, the effects of TA on the regulation of immune resistance, carbohydrate metabolism and biogenic monoamine, as well as its signaling pathway in Macrobrachium rosenbergii were determined. Results showed that total haemocyte count, hyaline cells, semigranular cells, and phenoloxidase activity per 50 μL of haemolymph and per granulocyte (the sum of semigranular and granular cells) at 0.5 h as well as phagocytic activity and clearance efficiency to Lactococcus garvieae at 1 h of prawn injected with TA at 1 nmol prawn -1 significantly increased, but the significantly decreased plasma lysozyme activity, phagocytic activity, clearance efficiency, and haemolymph glucose and dopamine were observed in prawn injected with TA at 10 nmol prawn -1 for 0.5 h. Respiratory bursts and haemolymph lactate in two TA-injection treatments at 0.5 h and 0.5-1 h, respectively, were significantly higher than those of the saline control, and in addition, TA depressed dopamine release in a dose-dependent manner after 0.5 h of TA injection. All the examined parameters returned to control levels after prawn injected with TA for 2 h. The inhibited effect of TA (at 10 nmol prawn -1 injection) on the phagocytic activity and clearance efficiency to pathogens was blocked by prazosin (an α1 adrenoceptors antagonist). For prawn received TA for 1 h then challenged with Lactococcus garvieae at 2 × 10 5  colony-forming units prawn -1 , the survival ratio of TA 1 nmol prawn -1 -injected prawn significantly increased by 20%, compared to the saline-challenged control or TA 10 nmol prawn -1 -injected prawn after 144 h of challenge. These results suggested that the level of dopamine release suppression regulated by TA resulted in the immunoenhancing or immunosuppressive effects in prawn, and the signaling pathways of TA in mediating immune function were through octopamine (OA)/TA receptors., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Lung cancer results in more patient deaths each year than any other cancer type. Additional treatment strategies are needed to improve clinical responses to approved treatment modalities and prevent the emergence of resistant disease. Catecholamines including norepinephrine and epinephrine are elevated as a result of chronic stress and mediate their physiological effects through activation of adrenergic receptors on target tissues. Lung cancer cells express β-adrenergic receptors (β-ARs), and numerous preclinical studies indicate that β2-AR signaling on lung cancer cells facilities cellular programs including proliferation, motility, apoptosis resistance, epithelial-to-mesenchymal transition, metastasis, and the acquisition of an angiogenic and immunosuppressive phenotype. Here, we review the preclinical and clinical evidence supporting a potential role for beta-blockers in improving the clinical outcome of lung cancer patients. Graphical Abstract Catecholamines including norepinephrine and epinephrine act of β-ARs expressed on NSCLC tumor cells and activate pathways regulating tumor progression.