Potentiating glymphatic drainage minimizes post-traumatic cerebral oedema.

Cerebral oedema is associated with morbidity and mortality after traumatic brain injury (TBI)1. Noradrenaline levels are increased after TBI2-4, and the amplitude of the increase in noradrenaline predicts both the extent of injury5 and the likelihood of mortality6. Glymphatic impairment is both a feature of and a contributor to brain injury7,8, but its relationship with the injury-associated surge in noradrenaline is unclear. Here we report that acute post-traumatic oedema results from a suppression of glymphatic and lymphatic fluid flow that occurs in response to excessive systemic release of noradrenaline. This post-TBI adrenergic storm was associated with reduced contractility of cervical lymphatic vessels, consistent with diminished return of glymphatic and lymphatic fluid to the systemic circulation. Accordingly, pan-adrenergic receptor inhibition normalized central venous pressure and partly restored glymphatic and cervical lymphatic flow in a mouse model of TBI, and these actions led to substantially reduced brain oedema and improved functional outcomes. Furthermore, post-traumatic inhibition of adrenergic signalling boosted lymphatic export of cellular debris from the traumatic lesion, substantially reducing secondary inflammation and accumulation of phosphorylated tau. These observations suggest that targeting the noradrenergic control of central glymphatic flow may offer a therapeutic approach for treating acute TBI.

Loss of p53 drives neuron reprogramming in head and neck cancer.

The solid tumour microenvironment includes nerve fibres that arise from the peripheral nervous system1,2. Recent work indicates that newly formed adrenergic nerve fibres promote tumour growth, but the origin of these nerves and the mechanism of their inception are unknown1,3. Here, by comparing the transcriptomes of cancer-associated trigeminal sensory neurons with those of endogenous neurons in mouse models of oral cancer, we identified an adrenergic differentiation signature. We show that loss of TP53 leads to adrenergic transdifferentiation of tumour-associated sensory nerves through loss of the microRNA miR-34a. Tumour growth was inhibited by sensory denervation or pharmacological blockade of adrenergic receptors, but not by chemical sympathectomy of pre-existing adrenergic nerves. A retrospective analysis of samples from oral cancer revealed that p53 status was associated with nerve density, which was in turn associated with poor clinical outcomes. This crosstalk between cancer cells and neurons represents mechanism by which tumour-associated neurons are reprogrammed towards an adrenergic phenotype that can stimulate tumour progression, and is a potential target for anticancer therapy.

Beta adrenergic receptor antagonist can modify Pseudomonas aeruginosa biofilm formation in vitro: Implications for chronic wounds.

Non-healing wounds are a major medical challenge, affecting over 6.5 million people in the US alone, with associated healthcare costs of about $16 billion annually. They can result in prolonged hospitalizations, work loss, disability, poor quality of life, and in diabetic patients with foot ulcers, amputation of the affected limb in 25% of patients. Though chronic ulcers may arise from different underlying diseases, the unifying feature is chronic infection, driving persistent inflammation that prolongs the healing process. One of the most frequently cultured or genetically identified pathogens in skin wounds is Pseudomonas aeruginosa. This species avidly forms biofilms in the wound that impede bacterial eradication by the host's immune mechanisms and limit efficacy of systemic antibiotics. Thus, non-antibiotic approaches to limit the growth and biofilm formation of this wound pathogen would be an advance in the treatment of chronic wounds. Prior work has demonstrated that the growth of other microbial species can be modulated by catecholamine agonists and antagonists of the adrenergic receptors (ARs). Here, we demonstrate that not only can the growth of this common wound pathogen be modulated by catecholamines, but also that the beta-AR antagonists can significantly decrease their growth, and importantly, limit their ability to form biofilms. These findings suggest that beta adrenergic antagonists may have a therapeutic role in the treatment of chronic skin wounds.

Alpha adrenergic receptors have role in the inhibitory effect of electrical low frequency stimulation on epileptiform activity in rats.

Aim: Low frequency stimulation (LFS) inhibits neuronal hyperexcitability following epileptic activity. However, knowledge about LFS' inhibitory mechanisms is lacking. Here, α1 and α2 adrenergic receptors' roles in mediating LFS inhibitory action on high-K+ induced epileptiform activity (EA) was examined in rat hippocampal slices.Materials and methods: LFS (1 Hz, 900 pulses) was applied to the Schaffer collaterals. Whole-cell, patch clamp recording was used to measure changes in CA1 pyramidal neurons' excitability. By applying high-K+ on hippocampal slices, EA was induced, and neuronal excitability increased.Results: When administered at the beginning of EA, LFS reduced neuronal excitability. In the presence of prazosin (10 µM, an α1 adrenergic receptor antagonist) and yohimbine (5 µM, an α2 adrenergic receptor antagonist), LFS' typically has a restorative impact on EA-induced membrane potential hyperpolarization and spike firing frequency, but this effect was reduced after high-K+ washout; These antagonists did not have a significant effect on LFS' inhibitory action on spike firing during EA.Conclusion: These findings suggest that LFS' anticonvulsant effect, on neuronal hyperexcitability following high-K+ EA, may be mediated partly through α adrenergic receptors in hippocampal slices.

Anticancer potential of yohimbine in drug-resistant oral cancer KB-ChR-8-5 cells.

BACKGROUND: The demand for environmentally friendly and cost-effective plant-based products for the development of cancer therapeutics has been increasing. Yohimbine (α2-adrenergic receptor antagonist) is a stimulant and aphrodisiac used to improve erectile dysfunction. In this study, we aimed to evaluate the anticancer potential of yohimbine in drug-resistant oral cancer KB-ChR-8-5 cells using different biomolecular techniques. METHODS: We estimated the anticancer efficacy of yohimbine using different assays, such as MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell cytotoxicity, cell morphology, cell apoptosis, reactive oxygen species (ROS) formation, and modulation in the mitochondrial membrane potential (MMP). RESULTS: Yohimbine showed a dose-dependent increase in cytotoxicity with a 50% inhibitory concentration (IC50) of 44 µM against KB-ChR-8-5 cancer cell lines. Yohimbine treatment at 40 µM and 50 µM resulted in a considerable change in cell morphology, including shrinkage, detachment, membrane blebbing, and deformed shape. Moreover, at the dose of IC50 and above, a significant induction was observed in the generation of ROS and depolarization of MMP. The possible mechanisms of action of yohimbine underlying the dose-dependent increase in cytotoxicity may be due to the induction of apoptosis, ROS generation, and modulation of MMP. CONCLUSION: Overall, yohimbine showed a significant anticancer potential against drug-resistant oral cancer KB-ChR-8-5 cells. Our study suggests that besides being an aphrodisiac, yohimbine can be used as a drug repurposing agent. However, more research is required in different in vitro and in vivo models to confirm the feasibility of yohimbine in clinics.

Adrenergic receptor antagonism induces neuroprotection and facilitates recovery from acute ischemic stroke.

Spontaneous waves of cortical spreading depolarization (CSD) are induced in the setting of acute focal ischemia. CSD is linked to a sharp increase of extracellular K+ that induces a long-lasting suppression of neural activity. Furthermore, CSD induces secondary irreversible damage in the ischemic brain, suggesting that K+ homeostasis might constitute a therapeutic strategy in ischemic stroke. Here we report that adrenergic receptor (AdR) antagonism accelerates normalization of extracellular K+, resulting in faster recovery of neural activity after photothrombotic stroke. Remarkably, systemic adrenergic blockade before or after stroke facilitated functional motor recovery and reduced infarct volume, paralleling the preservation of the water channel aquaporin-4 in astrocytes. Our observations suggest that AdR blockers promote cerebrospinal fluid exchange and rapid extracellular K+ clearance, representing a potent potential intervention for acute stroke.

Regulation of Cisplatin Resistance in Lung Cancer Cells by Nicotine, BDNF, and a ß-Adrenergic Receptor Blocker.

It is well-recognized that cigarette smoking is a primary risk factor in the development of non-small cell lung cancer (NSCLC), known to account for ~80% of all lung cancers with nicotine recognized as the major addictive component. In investigating the effect of nicotine, brain-derived neurotrophic factor (BDNF), and the ß-adrenergic receptor blocker, propranolol, on sensitivity of NSCLC cell lines, A549 and H1299, to cisplatin, we found increased cell viability, and enhanced cisplatin resistance with nicotine and/or BDNF treatment while opposite effects were found upon treatment with propranolol. Cell treatment with epinephrine or nicotine led to EGFR and IGF-1R activation, effects opposite to those found with propranolol. Blocking EGFR and IGF-1R activation increased cell sensitivity to cisplatin in both cell lines. PI3K and AKT activities were upregulated by nicotine or BDNF and downregulated by cell treatment with inhibitors against EGFR and IGF-1R and by propranolol. Apoptosis and cell sensitivity to cisplatin increased upon co-treatment of cells with cisplatin and inhibitors against PI3K or AKT. Our findings shed light on an interplay between nicotine, BDNF, and ß-Adrenergic receptor signaling in regulating survival of lung cancer cells and chemoresistance which can likely expand therapeutic opportunities that target this regulatory network in the future.

Left ventricular depression and pulmonary edema in rats after short-term normobaric hypoxia: effects of adrenergic blockade and reduced fluid load.

Acute normobaric hypoxia may induce pulmonary injury with edema (PE) and inflammation. Hypoxia is accompanied by sympathetic activation. As both acute hypoxia and high plasma catecholamine levels may elicit PE, we had originally expected that adrenergic blockade may attenuate the severity of hypoxic pulmonary injury. In particular, we investigated whether administration of drugs with reduced fluid load would be beneficial with respect to both cardiocirculatory and pulmonary functions in acute hypoxia. Rats were exposed to normobaric hypoxia (10% O2) over 1.5 or 6 h and received 0.9% NaCl or adrenergic blockers either as infusion (1 ml/h, increased fluid load) or injection (0.5 ml, reduced fluid load). Control animals were kept in normoxia and received infusions or injections of 0.9% NaCl. After 6 h of hypoxia, LV inotropic function was maintained with NaCl injection but decreased significantly with NaCl infusion. Adrenergic blockade induced a similar LV depression when fluid load was low, but did not further deteriorate LV depression after 6 h of infusion. Reduced fluid load also attenuated pulmonary injury after 6 h of hypoxia. This might be due to an effective fluid drainage into the pleural space. Adrenergic blockade could not prevent PE. In general, increased fluid load and impaired LV inotropic function promote the development of PE in acute hypoxia. The main physiologic conclusion from this study is that fluid reduction under hypoxic conditions has a protective effect on cardiopulmonary function. Consequently, appropriate fluid management has particular importance to subjects in hypoxic conditions.

Sympathomimetics regulate quantal acetylcholine release at neuromuscular junctions through various types of adrenoreceptors.

The studies of the interaction between the sympathetic and motor nervous systems are extremely relevant due to therapy for many neurodegenerative and cardiovascular disorders involving adrenergic compounds. Evidences indicate close contact between sympathetic varicosities and neuromuscular synapses. This raises questions about the effects of catecholamines on synaptic transmission. The currently available information is contradictory, and the types of adrenoreceptors responsible for modulation of neurotransmitter release have not been identified in mammalian neuromuscular synapses. Our results have shown that the α1A, α1B, α2A, α2B, α2C, and ß1 adrenoreceptor subtypes are expressed in mouse diaphragm muscle containing neuromuscular synapses and sympathetic varicosities. Pharmacological stimulation of adrenoreceptors affects both spontaneous and evoked acetylcholine quantal secretion. Agonists of the α1, α2 and ß1 adrenoreceptors decrease spontaneous release. Activation of the α2 and ß1 adrenoreceptors reduces the number of acetylcholine quanta released in response to a nerve stimulus (quantal content), but an agonist of the ß2 receptors increases quantal content. Activation of α2 and ß2 adrenoreceptors alters the kinetics of acetylcholine quantal release by desynchronizing the neurosecretory process. Specific blockers of these receptors eliminate the effects of the specific agonists. The action of blockers on quantal acetylcholine secretion indicates possible action of endogenous catecholamines on neuromuscular transmission. Elucidating the molecular mechanisms by which clinically utilized adrenomimetics and adrenoblockers regulate synaptic vesicle release at the motor axon terminal will lead to the creation of improved and safer sympathomimetics for the treatment of various neurodegenerative diseases with synaptic defects.

The Influence of an Adrenergic Antagonist Guanethidine on the Distribution Pattern and Chemical Coding of Caudal Mesenteric Ganglion Perikarya and Their Axons Supplying the Porcine Bladder.

This study was aimed at disclosing the influence of intravesically instilled guanethidine (GUA) on the distribution, relative frequency and chemical coding of both the urinary bladder intramural sympathetic nerve fibers and their parent cell bodies in the caudal mesenteric ganglion (CaMG) in juvenile female pigs. GUA instillation led to a profound decrease in the number of perivascular nerve terminals. Furthermore, the chemical profile of the perivascular innervation within the treated bladder also distinctly changed, as most of axons became somatostatin-immunoreactive (SOM-IR), while in the control animals they were found to be neuropeptide Y (NPY)-positive. Intravesical treatment with GUA led not only to a significant decrease in the number of bladder-projecting tyrosine hydroxylase (TH) CaMG somata (94.3 ± 1.8% vs. 73.3 ± 1.4%; control vs. GUA-treated pigs), but simultaneously resulted in the rearrangement of their co-transmitters repertoire, causing a distinct decrease in the number of TH+/NPY+ (89.6 ± 0.7% vs. 27.8 ± 0.9%) cell bodies and an increase in the number of SOM-(3.6 ± 0.4% vs. 68.7 ± 1.9%), calbindin-(CB; 2.06 ± 0.2% vs. 9.1 ± 1.2%) or galanin-containing (GAL; 1.6 ± 0.3% vs. 28.2 ± 1.3%) somata. The present study provides evidence that GUA significantly modifies the sympathetic innervation of the porcine urinary bladder wall, and thus may be considered a potential tool for studying the plasticity of this subdivision of the bladder innervation.

The Influence of an Adrenergic Antagonist Guanethidine (GUA) on the Distribution Pattern and Chemical Coding of Dorsal Root Ganglia (DRG) Neurons Supplying the Porcine Urinary Bladder.

Although guanethidine (GUA) was used in the past as a drug to suppress hyperactivity of the sympathetic nerve fibers, there are no available data concerning the possible action of this substance on the sensory component of the peripheral nervous system supplying the urinary bladder. Thus, the present study was aimed at disclosing the influence of intravesically instilled GUA on the distribution, relative frequency, and chemical coding of dorsal root ganglion neurons associated with the porcine urinary bladder. The investigated sensory neurons were visualized with a retrograde tracing method using Fast Blue (FB), while their chemical profile was disclosed with single-labeling immunohistochemistry using antibodies against substance P (SP), calcitonin gene-related peptide (CGRP), pituitary adenylate cyclase activating polypeptide (PACAP), galanin (GAL), neuronal nitric oxide synthase (nNOS), somatostatin (SOM), and calbindin (CB). After GUA treatment, a slight decrease in the number of FB+ neurons containing SP was observed when compared with untreated animals (34.6 ± 6.5% vs. 45.6 ± 1.3%), while the number of retrogradely traced cells immunolabeled for GAL, nNOS, and CB distinctly increased (12.3 ± 1.0% vs. 7.4 ± 0.6%, 11.9 ± 0.6% vs. 5.4 ± 0.5% and 8.6 ± 0.5% vs. 2.7 ± 0.4%, respectively). However, administration of GUA did not change the number of FB+ neurons containing CGRP, PACAP, or SOM. The present study provides evidence that GUA significantly modifies the sensory innervation of the porcine urinary bladder wall and thus may be considered a potential tool for studying the plasticity of this subdivision of the bladder innervation.

GPCR Pharmacological Profiling of Aaptamine from the Philippine Sponge Stylissa sp. Extends Its Therapeutic Potential for Noncommunicable Diseases.

We report the first isolation of the alkaloid aaptamine from the Philippine marine sponge Stylissa sp. Aaptamine possessed weak antiproliferative activity against HCT116 colon cancer cells and inhibited the proteasome in vitro at 50 µM. These activities may be functionally linked. Due to its known, more potent activity on certain G-protein coupled receptors (GPCRs), including α-adrenergic and δ-opioid receptors, the compound was profiled more broadly at sub-growth inhibitory concentrations against a panel of 168 GPCRs to potentially reveal additional targets and therapeutic opportunities. GPCRs represent the largest class of drug targets. The primary screen at 20 µM using the ß-arrestin functional assay identified the antagonist, agonist, and potentiators of agonist activity of aaptamine. Dose-response analysis validated the α-adrenoreceptor antagonist activity of aaptamine (ADRA2C, IC50 11.9 µM) and revealed the even more potent antagonism of the ß-adrenoreceptor (ADRB2, IC50 0.20 µM) and dopamine receptor D4 (DRD4, IC50 6.9 µM). Additionally, aaptamine showed agonist activity on selected chemokine receptors, by itself (CXCR7, EC50 6.2 µM; CCR1, EC50 11.8 µM) or as a potentiator of agonist activity (CXCR3, EC50 31.8 µM; CCR3, EC50 16.2 µM). These GPCRs play a critical role in the treatment of cardiovascular disease, diabetes, cancer, and neurological disorders. The results of this study may thus provide novel preventive and therapeutic strategies for noncommunicable diseases (NCDs).

Pyrophosphate therapy prevents trauma-induced calcification in the mouse model of neurogenic heterotopic ossification.

Trauma-induced calcification is the pathological consequence of complex injuries which often affect the central nervous system and other parts of the body simultaneously. We demonstrated by an animal model recapitulating the calcification of the above condition that adrenaline transmits the stress signal of brain injury to the calcifying tissues. We have also found that although the level of plasma pyrophosphate, the endogenous inhibitor of calcification, was normal in calcifying animals, it could not counteract the acute calcification. However, externally added pyrophosphate inhibited calcification even when it was administered after the complex injuries. Our finding suggests a potentially powerful clinical intervention of calcification triggered by polytrauma injuries which has no effective treatment.

Endosomal signaling of the receptor for calcitonin gene-related peptide mediates pain transmission.

G protein-coupled receptors (GPCRs) are considered to function primarily at the plasma membrane, where they interact with extracellular ligands and couple to G proteins that transmit intracellular signals. Consequently, therapeutic drugs are designed to target GPCRs at the plasma membrane. Activated GPCRs undergo clathrin-dependent endocytosis. Whether GPCRs in endosomes control pathophysiological processes in vivo and are therapeutic targets remains uncertain. We investigated the contribution of endosomal signaling of the calcitonin receptor-like receptor (CLR) to pain transmission. Calcitonin gene-related peptide (CGRP) stimulated CLR endocytosis and activated protein kinase C (PKC) in the cytosol and extracellular signal regulated kinase (ERK) in the cytosol and nucleus. Inhibitors of clathrin and dynamin prevented CLR endocytosis and activation of cytosolic PKC and nuclear ERK, which derive from endosomal CLR. A cholestanol-conjugated antagonist, CGRP8-37, accumulated in CLR-containing endosomes and selectively inhibited CLR signaling in endosomes. CGRP caused sustained excitation of neurons in slices of rat spinal cord. Inhibitors of dynamin, ERK, and PKC suppressed persistent neuronal excitation. CGRP8-37-cholestanol, but not unconjugated CGRP8-37, prevented sustained neuronal excitation. When injected intrathecally to mice, CGRP8-37-cholestanol inhibited nociceptive responses to intraplantar injection of capsaicin, formalin, or complete Freund's adjuvant more effectively than unconjugated CGRP8-37 Our results show that CLR signals from endosomes to control pain transmission and identify CLR in endosomes as a therapeutic target for pain. Thus, GPCRs function not only at the plasma membrane but also in endosomes to control complex processes in vivo. Endosomal GPCRs are a drug target that deserve further attention.

Breathing responses produced by optogenetic stimulation of adrenergic C1 neurons are dependent on the connection with preBötzinger complex in rats.

Optogenetic stimulation of the adrenergic C1 neurons produces cardiorespiratory activation, and selective depletion of these cells attenuates breathing responses induced by hypoxia. The preBötzinger complex (preBötC) is a group of neurons located in the intermediate aspect of the ventrolateral medulla, critical for respiratory rhythmogenesis, and is modulated by glutamate and catecholamines. Our hypothesis is that selective activation of C1 neurons leads to breathing responses by excitatory connections with the preBötC neurons. Anatomical connection between C1 cells and preBötC was evaluated using retrograde (Cholera Toxin b; preBötC) and anterograde (LVV-PRSx8-ChR2-eYFP; C1 region) tracers. LVV-PRSx8-ChR2-eYFP (viral vector that expresses channelrhodopsin-2 (ChR2) under the control of the catecholaminergic neuron-preferring promoter (PRSx8) was also injected into the C1 region of male Wistar rats for the functional experiments. Anatomical results demonstrated that preBötC neurons receive projections from C1 cells, and these projections express tyrosine hydroxylase and vesicular glutamate transporter 2. Functional connection between C1 cells and preBötC was evaluated by photostimulation of ChR2-transduced C1 neurons before and after unilateral injection of the ionotropic glutamate antagonist, kynurenic acid (kyn), or cocktail of adrenergic antagonists in the preBötC. Kyn injection into preBötC blocked the increase in DiaEMG frequency without changing the MAP increase elicited by photostimulation of C1 neurons, while the injection of adrenergic antagonists into the preBötC did not change DiaEMG frequency and MAP increase induced by photostimulation of C1 cells. Our results suggest that the increase in breathing produced by photostimulation of C1 neurons can be caused by a direct glutamatergic activation of preBötC neurons.

Non-adrenergic control of lipolysis and thermogenesis in adipose tissues.

The enormous plasticity of adipose tissues, to rapidly adapt to altered physiological states of energy demand, is under neuronal and endocrine control. In energy balance, lipolysis of triacylglycerols and re-esterification of free fatty acids are opposing processes operating in parallel at identical rates, thus allowing a more dynamic transition from anabolism to catabolism, and vice versa. In response to alterations in the state of energy balance, one of the two processes predominates, enabling the efficient mobilization or storage of energy in a negative or positive energy balance, respectively. The release of noradrenaline from the sympathetic nervous system activates lipolysis in a depot-specific manner by initiating the canonical adrenergic receptor-Gs-protein-adenylyl cyclase-cyclic adenosine monophosphate-protein kinase A pathway, targeting proteins of the lipolytic machinery associated with the interface of the lipid droplets. In brown and brite adipocytes, lipolysis stimulated by this signaling pathway is a prerequisite for the activation of non-shivering thermogenesis. Free fatty acids released by lipolysis are direct activators of uncoupling protein 1-mediated leak respiration. Thus, pro- and anti-lipolytic mediators are bona fide modulators of thermogenesis in brown and brite adipocytes. In this Review, we discuss adrenergic and non-adrenergic mechanisms controlling lipolysis and thermogenesis and provide a comprehensive overview of pro- and anti-lipolytic mediators.

Design, synthesis and cardiovascular evaluation of some aminoisopropanoloxy derivatives of xanthone.

A series of aminoisopropanoloxy derivatives of xanthone has been synthesized and their pharmacological properties regarding the cardiovascular system has been evaluated. Radioligand binding and functional studies in isolated organs revealed that title compounds present high affinity and antagonistic potency for α1-(compound 2 and 8), ß-(compounds 1, 3, 4, 7), α1/ß-(compounds 5 and 6) adrenoceptors. Furthermore, compound 7, the structural analogue of verapamil, possesses calcium entry blocking activity. The title compounds showed hypotensive and antiarrhythmic properties due to their adrenoceptor blocking effect. Moreover, they did not affect QRS and QT intervals, and they did not have proarrhythmic potential at tested doses. In addition they exerted anti-aggregation effect. The results of this study suggest that new compounds with multidirectional activity in cardiovascular system might be found in the group of xanthone derivatives.

Chemical Sympathectomy, but not Adrenergic Blockade, Improves Stroke Outcome.

BACKGROUND: A robust adrenergic response following stroke impairs lymphocyte function, which may prevent the development of autoimmune responses to brain antigens. We tested whether inhibition of the sympathetic response after stroke would increase the propensity for developing autoimmune responses to brain antigens. METHODS: Male Lewis rats were treated with 6-hydroxydopamine (OHDA) prior to middle cerebral artery occlusion (MCAO), labetalol after MCAO, or appropriate controls. Behavior was assessed weekly and animals survived to 1 month at which time ELISPOT assays were done on lymphocytes from spleen and brain to determine the Th1 and Th17 responses to myelin basic protein (MBP), ovalbumin (OVA), and concanavalin A. A subset of animals was sacrificed 72 hours after MCAO for evaluation of infarct volume and lymphocyte responsiveness. Plasma C-reactive protein (CRP) was measured as a biomarker of systemic inflammation. RESULTS: Despite similar initial stroke severity and infarct volumes, 6-OHDA-treated animals lost less weight and experienced less hyperthermia after stroke. 6-OHDA-treated animals also had decreased CRP in circulation early after stroke and experienced better neurological outcomes at 1 month. The Th1 and Th17 responses to MBP did not differ among treatment groups at 1 month, but the Th1 response to OVA in spleen was more robust in labetalol and less robust in 6-OHDA-treated animals. CONCLUSIONS: Chemical sympathectomy with 6-OHDA, but not treatment with labetalol, decreased systemic markers of inflammation early after stroke and improved long-term outcome. An increase in Th1 and Th17 responses to MBP was not seen with inhibition of the sympathetic response.

Nanobody-Enabled Reverse Pharmacology on G-Protein-Coupled Receptors.

The conformational complexity of transmembrane signaling of G-protein-coupled receptors (GPCRs) is a central hurdle for the design of screens for receptor agonists. In their basal states, GPCRs have lower affinities for agonists compared to their G-protein-bound active state conformations. Moreover, different agonists can stabilize distinct active receptor conformations and do not uniformly activate all cellular signaling pathways linked to a given receptor (agonist bias). Comparative fragment screens were performed on a ß2 -adrenoreceptor-nanobody fusion locked in its active-state conformation by a G-protein-mimicking nanobody, and the same receptor in its basal-state conformation. This simple biophysical assay allowed the identification and ranking of multiple novel agonists and permitted classification of the efficacy of each hit in agonist, antagonist, or inverse agonist categories, thereby opening doors to nanobody-enabled reverse pharmacology.

Antidepressant-like deliverables from the sea: evidence on the efficacy of three different brown seaweeds via involvement of monoaminergic system.

Brown seaweeds exhibit several health benefits in treating and managing wide array of ailments. In this study, the antidepressant-like effect of methaolic extracts from Sargassum swartzii (SS), Stoechospermum marginatum (SM), and Nizamuddinia zanardinii (NZ) was examined in forced swimming test (FST), in rats. Oral administration of SS, SM, and NZ extract (30-60 mg/kg) exhibited antidepressant-like activity in FST by reducing immobility time as compared to control group, without inducing significant change in ambulatory behavior in open field test. In order to evaluate the involvement of monoaminergic system, rats were pretreated with the inhibitor of brain serotonin stores p-chlorophenylalanin (PCPA), dopamine (SCH23390 and sulpiride), and adrenoceptor (prazosin and propranolol) antagonists. Rats receiving treatment for 28 days were decapitated and brains were analyzed for monoamine levels. It may be concluded that the extracts of SS, SM, and NZ produces antidepressant-like activity via modulation of brain monoaminergic system in a rat model.