Immunological abnormalities in young patients with dysautonomia

Abstracts / Autonomic Neuroscience: Basic and Clinical 192 (2015) 1–55

challenge triggers a powerful inhibitory reflex that suppresses the inflammatory response. Its efferent pathway, termed here the splanchnic anti-inflammatory pathway, is via the splanchnic sympathetic nerves, not the vagi as previously thought. We are now defining the target tissues for the anti-inflammatory action of the splanchnic nerves. doi:10.1016/j.autneu.2015.07.312

13.2 The suprachiasmatic nucleus is part of an autonomic anti inflammatory circuit R.M. Buijs, E. Soto-Tinoco, F. Cazarez-Marquez, N. Guerrero-Vargas Departamento de Fisiología Celular Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México DF 04510 Several studies have indicated the importance of time for the immune system. We have investigated the role of the suprachiasmatic nucleus (SCN) that gives time to all physiological processes in the body. We demonstrated a close interaction between the response of the immune system and the SCN; this interaction influences the intensity of the cytokine and temperature response. The activation of the SCN after an LPS challenge is aimed to curb the innate immune response. In order to investigate a potential mechanism by which the SCN could mediate this inhibition we denervated the liver either complete or partially. Only sympathetic denervation of the liver increased the TNF-α levels 10 fold indicating that the brain uses the sympathetic pathway to diminish the inflammatory response. Next we investigated the consequence of circadian disruption using a rat model of shift work. Shift work did not change basal TNF α levels neither in blood nor in the liver. Yet shift-work induced increased cytokines response after LPS stimulation in comparison to controls. Liver macrophages isolated from shift-work rats produced more TNF-α in response to in vitro LPS stimulation. In addition shift-work augmented the growth of subcutaneous implanted tumors, pointing to important changes in the immune defense system of shiftwork rats. When shift-work rats had no access to food during the working hours the inflammatory response to LPS was prevented. These results show that dissociating behavior and food intake from the synchronizing drive of the SCN severely disturbs the immune response and promotes disease. Grant support: Conacyt 220598 DGAPA IG 200314. doi:10.1016/j.autneu.2015.07.313

13.3 Sympathetic nervous crosstalk in chronic inflammation

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vascular effects in the joint, the sympathetic nervous system influences numerous immune processes in the joint and in lymphoid organs. Hence, the net effect of the sympathetic nervous system on inflamed tissue results from local sympathetic effects in the joint as well as from sympathetic influences on major systemic immune processes. doi:10.1016/j.autneu.2015.07.314

13.4 The sympathetic mesenteric nerve regulates experimental colitis R.A. Willemzea, L.E.J. Nijhuisa, O. Weltinga, J.H.A. Folgeringb, H. Darwinkelb, D. Chewc, A. Sridharc, J.E. Seppena, S.E.M. Heinsbroeka, W.J. de Jongea a Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, The Netherlands b Brains On-line B.V., Groningen, The Netherlands c Bioelectronics DPU, GlaxoSmithKline, UK Background: The autonomic nervous system plays a regulatory role in the immune response. It has been established that norepinephrine (NE) has anti-inflammatory effects on dendritic cell activation,1 which is a critical event in colitis pathophysiology. Our aim was to investigate the effect of sympathetic nerve activity on experimental colitis. Methods: 1) In a T-cell transfer colitis model, using Rag1−/− mice, sympathectomy was achieved chemically using 6-hydroxydopamine (6-OHDA) or surgically by cutting the supra mesenteric nerve (Sx). 2) In a dextran sodium sulfate (DSS) induced colitis model, mice underwent Sx or Sx combined with gastrointestinal-selective vagotomy (Cx) to assess the additive effect of the vagus nerve. Colitis was evaluated by histology and mRNA levels of inflammatory cytokines, along with clinical parameters such as weight loss and diarrhea. Ileal NE was measured by mass spectrometry. Results: 6-OHDA as well as Sx caused a significant decrease in ileal NE levels. In Rag1−/−, but not in wild type mice, Sx caused clinical signs of spontaneous colitis from day 8 and a significant increase of pro-inflammatory cytokines IL-1β and IL-6. 6-OHDA similarly elicited signs of colitis, but inflammatory cytokines were not significantly elevated. In DSS induced colitis, Cx aggravated colitis and increased IL-1β and IL-6 expression in the distal colon. Sx alone did not significantly affect IL-1β and IL-6 expression. Conclusion: Sympathetic innervation maintains homeostasis in the gut. Mucosal NE levels are critical determinants in maintaining mucosal tolerance towards luminal microbiota. Our data may explain how neuronal damage and plasticity contributes to pathology in IBD. 1) Nijhuis, L. E. et al. Adrenergic beta2 receptor activation stimulates anti-inflammatory properties of dendritic cells in vitro. PloS one 9, e85086, http://dx.doi.org/10.1371/journal.pone.0085086 (2014).

Rainer H. Straub Department of Internal Medicine I, University Hospital, 93042 Regensburg, Germany

doi:10.1016/j.autneu.2015.07.315

Joints are densely innervated by postganglionic sympathetic nerve fibers. These fibers control the blood flow in the joint and vascular permeability, either directly or indirectly, in cooperation with leukocytes. Chemical sympathectomy or suppression of adrenergic signaling significantly reduce inflammatory processes in the initial acute state of inflammation whereas the same procedures may increase inflammation at later stages. These findings indicate that the sympathetic nervous system supports the development of inflammation but may reduce inflammation at stages that are more chronic. During chronic inflammation, the density of sympathetic nerve fibers in synovial tissue is reduced but other tyrosine hydroxylase-positive cells secreting noradrenaline appear in the inflamed joint. In addition to local

13.5 Immunological abnormalities in young patients with dysautonomia S.E. Pacheco, I.J. Butler, J. Lankford, A. Gourishankar, M.T. Numan University of Texas, School of Medicine, Houston, Texas Background: Dysautonomia is a poorly understood condition of unknown etiology. Many patients with dysautonomia have symptoms suggestive of immune dysregulation but there is limited information on their immunologic phenotype. Our aim is to characterize the association between dysautonomia and immunity in a group of young patients with this condition. Methods: A retrospective chart review was conducted in

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Abstracts / Autonomic Neuroscience: Basic and Clinical 192 (2015) 1–55

a group of patients with dysautonomia, documented by an abnormal head-up tilt test, referred for immune evaluation to the AllergyImmunology clinic at our institution (2007–2014). Their clinical history and immune laboratory studies (e.g. immunoglobulin levels, specific antibody responses, ANA, anti-SSA/SSO, dysautonomia autoimmune profile, serum cytokines) were reviewed. Results: Twenty patients (3 males, 17 females), mean age of 19.9 years (15–34), were evaluated. Symptoms suggestive of immune dysfunction included arthralgia (7), joint swelling (3), backache (2), dermatitis (5), alopecia (2), sicca (4), Raynaud’s (1), and recurrent infections (5). Five patients (25%) had autoantibodies (i.e. anti-SSA, ANA, anti-GAD65, folate receptor autoantibodies), and 9 of 14 patients (64%), had elevated serum cytokines. Severe dysautonomia was present in one patient with IDDM and 4 patients with B-cell immunodeficiency, all of which had other coexisting autoimmune problems. Conclusions: Young patients with dysautonomia may suffer from immune dysregulation and the severity of their disease is associated with severe dysautonomia. It remains to be determined if this immune dysregulation is a primary or secondary process. doi:10.1016/j.autneu.2015.07.316

SYMPOSIUM 14: ANGIOTENSIN RECEPTORS WITHIN THE BRAIN: NEW INSIGHTS ON CARDIOVASCULAR REGULATION DURING HYPERTENSION 14.1 Role of angiotensin type 1A receptors in the sympathetic activation of angiotensin-dependent hypertension N. Jancovskia, D.A. Cartera, D. Chena, Y.T. Choonga, T.P. Nguyenb, E. Lukoshkovac, A.A. Connellya, J.K. Bassia, G.A. Headb, C. Menueta, A.M. Allena a Department of Physiology, University of Melbourne, Australia b Baker IDI Heart and Diabetes Research Institute, Australia c Department of Cardiovascular Regulation, Russian Cardiology Research Center, Russia Prolonged low dose infusion of angiotensin II (AngII) acts via its type 1A receptor (AT1AR) to induce a sustained increase in blood pressure. We aimed to investigate whether targeted deletion of AT1ARs from catecholaminergic cells would affect the response to sustained infusion of AngII. Mice (C57Bl/6 background) with global, or regionally-selective deletion of the AT1AR from catecholaminergic cells were generated. Blood pressure and heart rate were recorded. Hypertension was induced by subcutaneous infusion of Ang II (500 ng/kg/min by osmotic minipump) for 4 weeks. Basal systolic blood pressure and heart rate were not different between any groups. Infusion of Ang II in control mice induced a gradual pressor response that was increased above baseline by day 5 of infusion. The maximal change in BP occurred at day 13. The trajectory of the BP increase was less in the mice with global deletion of the AT1AR from all catecholaminergic cells - the maximal response at day 13 of infusion was 150 ± 3 mmHg in controls and 133 ± 2 mmHg in knockouts; P b 0.05). The reduced pressor response was associated with reduced fluid and electrolyte retention, reduced activation of the sympathetic nervous system and loss of superoxide formation in key brain cardiovascular nuclei. AT1AR knockout from catecholaminergic cells does not elicit changes in metabolic state, baseline systolic BP or HR but expression of the receptor by these cells is essential for the full development of AngII hypertension. doi:10.1016/j.autneu.2015.07.317

14.2 Antioxidant proteins in the brain: Role in RAS-induced blood pressure control and hypertension Colin Sumners Department of Physiology & Functional Genomics, University of Florida College of Medicine, USA Over activity of the renin-angiotensin system at brain cardiovascular control centers, particularly angiotensin II acting via its type 1 receptors (AT1R), is an important contributor to the chronic sympathoexcitation that characterizes hypertension of neurogenic origin. Thus it is important to uncover mechanisms that attenuate AT1R-mediated actions and potentially lower blood pressure. To this end we have identified the cytokine and anti-oxidant protein macrophage migration inhibitory factor (MIF) as an inhibitor of the central actions of angiotensin II, and investigated whether it was able to lower blood pressure in animal models of hypertension that are characterized by enhanced AT1R activation and sympathoexcitation. This presentation will summarize our studies using a combination of whole animal, molecular and gene transfer methods which have demonstrated that increased neuronal expression of MIF within brain cardiovascular control centers such as the paraventricular nucleus and the solitary tract nucleus exerts significant antihypertensive actions in spontaneously hypertensive rats and 2 kidney 1clip hypertensive rats, and in stress-induced hypertension. While our studies point to an anti-oxidant action of MIF in lowering blood pressure, the data also suggest that other mechanisms play a role. These studies, which will be discussed, include: decreasing the expression of pro-inflammatory cytokines in cardiovascular control centers, and induction of blood pressure lowering angiotensin type 2 receptors. Collectively, these studies indicate a potentially important action of MIF in the brain in lowering blood pressure.

doi:10.1016/j.autneu.2015.07.318

14.3 Angiotensin type 2 receptors within solitary-vagal complex: Role on autonomic control and hypertension D.S.A. Colombari Department of Physiology and Pathology, School of Dentistry, UNESP, Araraquara, Brazil Spontaneously (SHR) and renovascular hypertensive 2-kidney 1-clip (2K1C) rats exhibit an increased activity of the peripheral and central renin-angiotensin system. Therefore, in this study we investigate the effects of increased angiotensin II type 2 receptor (AT2R) expression in the solitary-vagal complex (nucleus of the solitary tract/dorsal motor nucleus of the vagus; NTS/DVM) on high blood pressure and baroreflex function in SHR and 2K1C rats. Microinjections of either an adeno-associated virus expressing AT2R or enhanced green fluorescent protein (control; eGFP) into the NTS/ DVM were performed 3 weeks after the induction of 2K1C and in 10 week old SHR (n = 5-7/group). Four weeks after AT2R transduction in the NTS/DMV of 2K1C rats we observed an attenuation of the hypertension (154 ± 7 vs. 2K1C-eGFP: 179 ± 11 mmHg) and an improvement of the baroreflex (−1.45 ± 0.072 vs. 2K1C-eGFP: −0.95 ± 0.05 bpm/mmHg), whereas in SHR only the baroreflex was improved (−1.84 ± 0.30 vs. SHR-eGFP: −0.77 ± 0.35 bpm/mmHg). In 2K1C-AT2R rats mRNA levels of angiotensin converting enzyme 2 (ACE2) in the NTS/DMV was restored to control levels at this site. In SHR, mRNA levels of angiotensin converting enzyme and ACE2 were