Sympathetic Nerves and Innate Immune System in the Spleen: Implications of Impairment in HIV-1 and Relevant Models.

The immune and sympathetic nervous systems are major targets of human, murine and simian immunodeficiency viruses (HIV-1, MAIDS, and SIV, respectively). The spleen is a major reservoir for these retroviruses, providing a sanctuary for persistent infection of myeloid cells in the white and red pulps. This is despite the fact that circulating HIV-1 levels remain undetectable in infected patients receiving combined antiretroviral therapy. These viruses sequester in immune organs, preventing effective cures. The spleen remains understudied in its role in HIV-1 pathogenesis, despite it hosting a quarter of the body's lymphocytes and diverse macrophage populations targeted by HIV-1. HIV-1 infection reduces the white pulp, and induces perivascular hyalinization, vascular dysfunction, tissue infarction, and chronic inflammation characterized by activated epithelial-like macrophages. LP-BM5, the retrovirus that induces MAIDS, is a well-established model of AIDS. Immune pathology in MAIDs is similar to SIV and HIV-1 infection. As in SIV and HIV, MAIDS markedly changes splenic architecture, and causes sympathetic dysfunction, contributing to inflammation and immune dysfunction. In MAIDs, SIV, and HIV, the viruses commandeer splenic macrophages for their replication, and shift macrophages to an M2 phenotype. Additionally, in plasmacytoid dendritic cells, HIV-1 blocks sympathetic augmentation of interferon-ß (IFN-ß) transcription, which promotes viral replication. Here, we review viral-sympathetic interactions in innate immunity and pathophysiology in the spleen in HIV-1 and relevant models. The situation remains that research in this area is still sparse and original hypotheses proposed largely remain unanswered.

Psychosocial Stress and Age Influence Depression and Anxiety-Related Behavior, Drive Tumor Inflammatory Cytokines and Accelerate Prostate Cancer Growth in Mice.

Prostate cancer (PCa) prevalence is higher in older men and poorer coping with psychosocial stressors effect prognosis. Yet, interactions between age, stress and PCa progression are underexplored. Therefore, we characterized the effects of age and isolation combined with restraint (2 h/day) for 14 days post-tumor inoculation on behavior, tumor growth and host defense in the immunocompetent, orthotopic RM-9 murine PCa model. All mice were tumor inoculated. Isolation/restraint increased sympathetic and hypothalamic-pituitary-adrenal cortical activation, based on elevated serum 3-methoxy-4-hydroxyphenylglycol/norepinephrine ratios and corticosterone levels, respectively. Elevated zero maze testing revealed age-related differences in naïve C57Bl/6 mice, and increased anxiety-like behavior in tumor-bearing mice. In open field testing, old stressed mice were less active throughout the 30-min test than young non-stressed and stressed, and old non-stressed mice, suggesting greater anxiety in old stressed mice. Old (18 month) mice demonstrated more depression-like behavior than young mice with tail suspension testing, without effects of isolation/restraint stress. Old mice developed larger tumors, despite similar tumor expression of tumor vascular endothelial growth factor or transforming growth factor-beta1 across age. Tumor chemokine/cytokine expression, commonly prognostic for poorer outcomes, were uniquely age- and stress-dependent, underscoring the need for PCa research in old animals. Macrophages predominated in RM-9 tumors. Macrophages, and CD4+ and CD4+FoxP3+ T-cell tumor infiltration were greater in young mice than in old mice. Stress increased macrophage infiltration in old mice. Conversely, stress reduced intratumoral CD4+ and CD4+FoxP3+ T-cell numbers in young mice. CD8+ T-cell infiltration was similar across treatment groups. Our findings support that age- and psychological stress interacts to affect PCa outcomes by interfering with neural-immune mechanisms and affecting behavioral responses.

Driving ß2- While Suppressing α-Adrenergic Receptor Activity Suppresses Joint Pathology in Inflammatory Arthritis.

Objective: Hypersympathetic activity is prominent in rheumatoid arthritis, and major life stressors precede onset in ~80% of patients. These findings and others support a link between stress, the sympathetic nervous system and disease onset and progression. Here, we extend previous research by evaluating how selective peripherally acting α/ß2-adrenergic drugs affect joint destruction in adjuvant-induced arthritis. Methods: Complete Freund's adjuvant induced inflammatory arthritis in male Lewis rats. Controls received no treatment. Arthritic rats then received vehicle or twice-daily treatment with the α-adrenergic antagonist, phentolamine (0.5 mg/day) and the ß2-adrenergic agonist, terbutaline (1200 µg/day, collectively named SH1293) from day (D) of disease onset (D12) through acute (D21) and severe disease (D28). Disease progression was assessed in the hind limbs using dorsoplantar widths, X-ray analysis, micro-computed tomography, and routine histology on D14, D21, and D28 post-immunization. Results: On D21, SH1293 significantly attenuated arthritis in the hind limbs, based on reduced lymphocytic infiltration, preservation of cartilage, and bone volume. Pannus formation and sympathetic nerve loss were not affected by SH1293. Bone area and osteoclast number revealed high- and low-treatment-responding groups. In high-responding rats, treatment with SH1293 significantly preserved bone area and decreased osteoclast number, data that correlated with drug-mediated joint preservation. SH1293 suppressed abnormal bone formation based on reduced production of osteophytes. On D28, the arthritic sparing effects of SH1293 on lymphocytic infiltration, cartilage and bone sparing were maintained at the expense of bone marrow adipocity. However, sympathetic nerves were retracted from the talocrural joint. Conclusion and Significance: Our findings support a significant delay in early arthritis progression by treatment with SH1293. Targeting sympathetic neurotransmission may provide a strategy to slow disease progression.

Loss of APP in mice increases thigmotaxis and is associated with elevated brain expression of IL-13 and IP-10/CXCL10.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that leads to memory loss and is often accompanied by increased anxiety. Although AD is a heterogeneous disease, dysregulation of inflammatory pathways is a consistent event. Interestingly, the amyloid precursor protein (APP), which is the source of the amyloid peptide Aß, is also necessary for the efficient regulation of the innate immune response. Here, we hypothesize that loss of APP function in mice would lead to cognitive loss and anxiety behavior, both of which are typically present in AD, as well as changes in the expression of inflammatory mediators. To test this hypothesis, we performed open field, Y-maze and novel object recognition tests on 12-18-week-old male and female wildtype and AppKO mice to measure thigmotaxis, short-term spatial memory and long-term recognition memory. We then performed a quantitative multiplexed immunoassay to measure levels of 32 cytokines/chemokines associated with AD and anxiety. Our results showed that AppKO mice, compared to wildtype controls, experienced increased thigmotactic behavior but no memory impairments, and this phenotype correlated with increased IP-10 and IL-13 levels. Future studies will determine whether dysregulation of these inflammatory mediators contributes to pathogenesis in AD.

Short-term exposure to dietary cholesterol is associated with downregulation of interleukin-15, reduced thigmotaxis and memory impairment in mice.

Alzheimer's disease (AD) is a neurodegenerative condition associated with loss of memory function, depression and anxiety. The etiology of AD is poorly understood, but both cholesterol dyshomeostasis and dysregulation of the immune system are contributing factors. Current evidence is consistent with a detrimental effect of excess cholesterol on neuroinflammation, both in mouse models of memory loss and in dementia in humans. However, whether the impact of cholesterol on neuroinflammation occurs early and contributes to pathogenesis of the disease or simply reflects a pleiotropic impact at advanced stages of disease is unclear. To explore this question, we measured, in 9-13 week-old mice, cognitive status and changes in brain inflammatory mediators in response to a short-term high-cholesterol diet. We hypothesized that short-term exposure to excess dietary cholesterol would alter the early inflammatory responses associated with cognitive and/or behavioral impairment. We report that short-term exposure to a high-cholesterol diet led to decreased thigmotaxis and short-term spatial memory impairment without affecting long-term recognition memory. Furthermore, cognitive and behavioral phenotypes in these mice were associated with a reduction in interleukin-15 levels in the absence of changes in other inflammatory mediators. Our findings indicate that interleukin-15 may play a role in early stages of cognitive impairment secondary to hypercholesterolemia. Consequently, optimization of interleukin-15 signaling may be a viable effective cognitive therapy in the population susceptible to developing dementia due to risk factors associated with cholesterol dysregulation.

Maternal plasma proteomics in a rat model of pregnancy complications reveals immune and pro-coagulant gene pathway activation.

PROBLEM: The Brown Norway (BN) rat is a model of T-helper 2 immune diseases, and also a model of pregnancy disorders that include placental insufficiency, fetal loss, and pre-eclampsia-like symptoms. The aim of this study was to investigate the plasma proteomic/cytokine profile of pregnant BN rats in comparison to that of the Lewis (LEW) rat strain. METHOD OF STUDY: Plasma proteomics differences were studied at day 13 of pregnancy in pooled plasma samples by differential in-gel electrophoresis, and protein identification was performed by mass spectrometry. Key protein findings and predicted cytokine differences were validated by ELISA using plasma from rats at various pregnancy stages. Proteomics data were used for ingenuity pathway analysis (IPA). RESULTS: In-gel analysis revealed 74 proteins with differential expression between BN and LEW pregnant dams. ELISA studies confirmed increased maternal plasma levels of complement 4, prothrombin, and C-reactive protein in BN compared to LEW pregnancies. LEW pregnancies showed higher maternal plasma levels of transthyretin and haptoglobin than BN pregnancies. Ingenuity pathway analysis revealed that BN pregnancies are characterized by activation of pro-coagulant, reactive oxygen species, and immune-mediated chronic inflammation pathways, and suggested increased interleukin 6 and decreased transforming growth factor-ß1 as potential upstream events. Plasma cytokine analysis revealed that pregnant BN dams have a switch from anti- to pro-inflammatory cytokines with the opposite switch observed in pregnant LEW dams. CONCLUSION: Brown Norway rats show a maternal pro-inflammatory response to pregnancy that likely contributes to the reproductive outcomes observed in this rat strain.

Loss of amyloid precursor protein exacerbates early inflammation in Niemann-Pick disease type C.

BACKGROUND: Niemann-Pick disease type C (NPC) is a progressive neurodegenerative condition that results in early fatality. NPC is inherited in an autosomal recessive pattern from mutations in NPC1 or NPC2 genes. The etiology of NPC is poorly defined. In that regard, neuroinflammation occurs early in the disease and we have recently unveiled an atypical pattern of interferon signaling in pre-symptomatic Npc1-/- mice, with microglial activation, anti-viral response, activation of antigen-presenting cells, and activation and chemotaxis of T lymphocytes as the key affected pathologic pathways. Furthermore, IP-10/CXCL10, a potent IFN-γ-responsive cytokine, was identified as the potential mediator of these early inflammatory abnormalities. Here, we asked whether this aberrant signaling may be exacerbated by the loss of amyloid precursor protein (APP) function, a loss known to shorten lifespan and accelerate neurodegeneration in Npc1-/- mice. METHODS: We carried out genome-wide comparative transcriptome analyses of pre-symptomatic Npc1+/+/App+/+, Npc1-/-/App+/+, Npc1+/+/App-/-, and Npc1-/-/App-/- mouse cerebella to identify biological pathways in the NPC brain further affected by the loss of APP. Gene Set Enrichment Analysis and Ingenuity Pathway Analysis were utilized for molecular mapping and functional upstream pathway analyses of highly differentially expressed genes. We simultaneously measured the expression of 32 inflammatory cytokines and chemokines in the cerebella from these mice, including those identified in our genome-wide analyses. Finally, we used immunohistochemistry to measure T cell infiltration in the cerebellum. RESULTS: Expression of IFN-γ- and IFN-α-responsive genes in pre-symptomatic Npc1-/-/App-/- cerebella is upregulated compared with Npc1-/-/App+/+ mice, compounding the dysregulation of microglial activation, anti-viral response, activation of antigen-presenting cells, and T-lymphocyte activation and chemotaxis pathways present in the NPC brain. Multiplex protein analysis further showed elevated expression of IP-10/CXCL10, a potent downstream effector of IFN-γ, as well as RANTES/CCL5, eotaxin/CCL11 and IL-10, prior to symptomatic onset in Npc1-/-/App-/- cerebella, compared with Npc1-/-/App+/+mice. In the terminal disease stage, loss of APP caused pleiotropic differential expression of the vast majority of cytokines evaluated. Finally, we present evidence of T cell infiltration in Npc1-/-/App-/- cerebella. CONCLUSIONS: Loss of APP exacerbates the pathogenic neuroinflammation that occurs prior to symptomatic onset in the NPC brain. These findings shed new light on the function of APP as a cytoprotective modulator in the CNS, offering potential evidence-based therapies against NPC.

The Association between Affect and Biomarkers of Stress and Inflammation in Healthy Seventh-Day Adventists.

OBJECTIVE: To evaluate the association between positive and negative affective states with stress biomarkers, biomarkers of inflammation and blood pressure in a population of healthy Seventh-day Adventists. DESIGN: In a cross-sectional study, biomarkers were regressed on positive and negative affect and control variables among reportedly healthy 133 females and 100 males (35% Black and 65% White) who provided blood and urine samples following completion of a questionnaire and measurement of anthropometrics and vital signs. SETTING/LOCATION: Data were extracted from the Biological Manifestations of Religion Study, an NIA-funded study conducted in members of the entity who lived within driving distance of two clinic sites. OUTCOME MEASURES: The stress biomarkers, epinephrine, and norepinephrine, were measured in 12-hour overnight urine samples analyzed by high-performance liquid chromatography. Urinary cortisol was evaluated by enzyme-linked immunosorbent assay (ELISA) and normalized for urinary output (reported in µg/g creatinine). Serum DHEA-S (reported in µg/ml) was measured by ELISA. Inflammatory markers included CRP (ng/ml), IL-6, IL-10, and TNF-α, all analyzed in serum by ELISA, and the data expressed in pg/ml. RESULTS: Multiple linear regression analyses showed after controlling for age, gender, ethnicity, body mass index (BMI), education, socioeconomic status, exercise, and use of blood pressure medication, that negative affect was associated with higher levels of epinephrine (ß = .143; P = .030). Positive affect was not associated with the biomarkers. CONCLUSIONS: While negative affect was associated with a biomarker of sympathetic stimulation, positive affect was not protective against such stimulation.

Interferon downstream signaling is activated early in pre-symptomatic Niemann-Pick disease type C.

Niemann-Pick disease type C (NPC) is a fatal neurodegenerative condition with no FDA-approved therapy. Previous studies demonstrated that neuroinflammation is an early pathologic event and a disease modifier of NPC, affecting symptomatic onset and overall lifespan. Therefore, NPC-specific anti-inflammatory therapy may result in clinical benefit. However, to date, the initial trigger of the inflammatory onset and the mechanism driving the sustained chronic neuroinflammation remain unknown. In this study, we utilized a genome-wide transcriptome analysis to identify the key pathways involved in early NPC. Our results showed that an atypical pattern of interferon downstream signaling that involves both IFN-γ- and IFN-α-responsive genes is activated in pre-symptomatic Npc1-/- cerebella. Functional analysis of the differentially expressed genes highlighted microglial activation, anti-viral response, and T-lymphocyte activation and chemotaxis pathways. Multiplex protein analysis confirmed that a potent IFN-γ-responsive cytokine, IP-10/CXCL10 was significantly upregulated in the pre-symptomatic stage and further exacerbated in the terminal stage. In addition, several IFN-γ-responsive cytokines were elevated in the terminal stage Npc1-/- cerebella, including MIG/CXCL9, MCP-1/CCL2, MIP-1α/CCL3, MIP-1ß/CCL4, RANTES/CCL5, M-CSF, and IL-1α. Together, our results describe a novel activation pattern of interferon downstream signaling in pre-symptomatic NPC, as well as key inflammatory mediators that could serve as potential targets for NPC-specific anti-inflammatory therapy.

Changes in the Morphology of Hypoglossal Motor Neurons in the Brainstem of Developing Rats.

The autonomic brainstem generates breathing rhythm by integrating inputs from chemosensors and mechanosensors in the viscera and coordinating descending outputs from higher structures in the central nervous system. Hypoglossal motoneurons (XII MNs) receive inputs from respiratory premotor neurons, important for maintaining airway patency. Previous studies in rodents report significant changes in breathing control during the first 3 weeks of life, with a sensitive period at 10 to 13 days postbirth (P10-P13) characterized by pronounced changes in neurotransmitters, excitation-inhibition balance, and breathing physiology. However, age-dependent morphological changes of XII MNs during the first 3 weeks postbirth and especially this sensitive period are under-studied. Here, we comprehensively characterize and quantify the early morphological changes in rat XII MNs. We hypothesized that morphological changes in XII MNs correspond to the functionally defined sensitive period observed at postnatal day 10-13 (P10-P13). To test this hypothesis, we used an innovative contemporary statistical approach to analyze Golgi-Cox stained XII MNs at nine postnatal ages between P1 and P21. Our findings reveal two subpopulations of XII MNs, which are dependent on age and morphological features. Soma size increased approximately 40% from P1 to P21, without changing shape. However, dendritic arborization increased in extent/distance and complexity. Dendritic branching of developing neurons significantly increased from P1 through P13, with the greatest increase at P10-P13 based on the Sholl method. Our detailed characterization of XII MN morphological development establishes a foundation for the study and elucidation of morphological changes caused by maternal and perinatal conditions. Anat Rec, 302:869-892, 2019. © 2018 Wiley Periodicals, Inc.

Sympathetic neurotransmission in spleens from aging Brown-Norway rats subjected to reduced sympathetic tone.

Senescence of innate and adaptive responses and low-grade inflammation (inflammaging) hallmarks normal aging, which increases vulnerability to infectious diseases, autoimmunity and cancer. In normal aging, sympathetic dysregulation contributes to the dysregulation of innate and adaptive immunity and inflammaging. Sympathetic innervation of immune cells in secondary immune organs regulates immune responses. Previously in Fischer 344 (F344) rats, we reported an age-related increase in sympathetic tone and sympathetic dysfunction in beta-adrenergic receptor (AR) signaling of splenic lymphocytes that contributes to immune senescence, although the responsible mechanisms remains unexplored. In this study, we extend our previous findings using the much longer-lived Brown-Norway (BN) rats, whose behavior and immune response profile differ strikingly from F344 rats. Here, we investigated whether increased sympathetic nerve activity (SNA) in the aging spleen contributes to age-related sympathetic neuropathy and altered neurotransmission in splenic lymphocytes in BN rats. Fifteen-month male BN rats received 0, 0.5 or 1.5 µg/kg/day rilmenidine intraperitoneally for 90 days to lower sympathetic tone. Untreated young and age-matched rats controlled for effects of age. We found that elevated SNA in the aging BN rat spleen does not contribute significantly to sympathetic neuropathy or the aging-induced impairment of canonical ß-AR signal transduction. Despite the rilmenidine-induced increase in ß-AR expression, splenocyte c-AMP production was comparable with age-matched controls, thus dampening nerve activity had no effect on receptor coupling to adenylate cyclase. Understanding how aging affects neuroimmune regulation in healthy aging rodent models may eventually lead to strategies that improve health in aging populations vulnerable to immunosenescence and low-grade systemic inflammation.

Sympathetic Nerve Hyperactivity in the Spleen: Causal for Nonpathogenic-Driven Chronic Immune-Mediated Inflammatory Diseases (IMIDs)?

Immune-Mediated Inflammatory Diseases (IMIDs) is a descriptive term coined for an eclectic group of diseases or conditions that share common inflammatory pathways, and for which there is no definitive etiology. IMIDs affect the elderly most severely, with many older individuals having two or more IMIDs. These diseases include, but are not limited to, type-1 diabetes, obesity, hypertension, chronic pulmonary disease, coronary heart disease, inflammatory bowel disease, and autoimmunity, such as rheumatoid arthritis (RA), Sjogren's syndrome, systemic lupus erythematosus, psoriasis, psoriatic arthritis, and multiple sclerosis. These diseases are ostensibly unrelated mechanistically, but increase in frequency with age and share chronic systemic inflammation, implicating major roles for the spleen. Chronic systemic and regional inflammation underlies the disease manifestations of IMIDs. Regional inflammation and immune dysfunction promotes targeted end organ tissue damage, whereas systemic inflammation increases morbidity and mortality by affecting multiple organ systems. Chronic inflammation and skewed dysregulated cell-mediated immune responses drive many of these age-related medical disorders. IMIDs are commonly autoimmune-mediated or suspected to be autoimmune diseases. Another shared feature is dysregulation of the autonomic nervous system and hypothalamic pituitary adrenal (HPA) axis. Here, we focus on dysautonomia. In many IMIDs, dysautonomia manifests as an imbalance in activity/reactivity of the sympathetic and parasympathetic divisions of the autonomic nervous system (ANS). These major autonomic pathways are essential for allostasis of the immune system, and regulating inflammatory processes and innate and adaptive immunity. Pathology in ANS is a hallmark and causal feature of all IMIDs. Chronic systemic inflammation comorbid with stress pathway dysregulation implicate neural-immune cross-talk in the etiology and pathophysiology of IMIDs. Using a rodent model of inflammatory arthritis as an IMID model, we report disease-specific maladaptive changes in ß2-adrenergic receptor (AR) signaling from protein kinase A (PKA) to mitogen activated protein kinase (MAPK) pathways in the spleen. Beta2-AR signal "shutdown" in the spleen and switching from PKA to G-coupled protein receptor kinase (GRK) pathways in lymph node cells drives inflammation and disease advancement. Based on these findings and the existing literature in other IMIDs, we present and discuss relevant literature that support the hypothesis that unresolvable immune stimulation from chronic inflammation leads to a maladaptive disease-inducing and perpetuating sympathetic response in an attempt to maintain allostasis. Since the role of sympathetic dysfunction in IMIDs is best studied in RA and rodent models of RA, this IMID is the primary one used to evaluate data relevant to our hypothesis. Here, we review the relevant literature and discuss sympathetic dysfunction as a significant contributor to the pathophysiology of IMIDs, and then discuss a novel target for treatment. Based on our findings in inflammatory arthritis and our understanding of common inflammatory process that are used by the immune system across all IMIDs, novel strategies to restore SNS homeostasis are expected to provide safe, cost-effective approaches to treat IMIDs, lower comorbidities, and increase longevity.

Is spaceflight-induced immune dysfunction linked to systemic changes in metabolism?

The Space Shuttle Atlantis launched on its final mission (STS-135) on July 8, 2011. After just under 13 days, the shuttle landed safely at Kennedy Space Center (KSC) for the last time. Female C57BL/6J mice flew as part of the Commercial Biomedical Testing Module-3 (CBTM-3) payload. Ground controls were maintained at the KSC facility. Subsets of these mice were made available to investigators as part of NASA's Bio-specimen Sharing Program (BSP). Our group characterized cell phenotype distributions and phagocytic function in the spleen, catecholamine and corticosterone levels in the adrenal glands, and transcriptomics/metabolomics in the liver. Despite decreases in most splenic leukocyte subsets, there were increases in reactive oxygen species (ROS)-related activity. Although there were increases noted in corticosterone levels in both the adrenals and liver, there were no significant changes in catecholamine levels. Furthermore, functional analysis of gene expression and metabolomic profiles suggest that the functional changes are not due to oxidative or psychological stress. Despite changes in gene expression patterns indicative of increases in phagocytic activity (e.g. endocytosis and formation of peroxisomes), there was no corresponding increase in genes related to ROS metabolism. In contrast, there were increases in expression profiles related to fatty acid oxidation with decreases in glycolysis-related profiles. Given the clear link between immune function and metabolism in many ground-based diseases, we propose a similar link may be involved in spaceflight-induced decrements in immune and metabolic function.

Effects of a meal replacement system alone or in combination with phentermine on weight loss and food cravings.

OBJECTIVE: To examine the effects of phentermine combined with a meal replacement program on weight loss and food cravings and to investigate the relationship between food cravings and weight loss. METHODS: In a 12-week randomized, double-blind, placebo-controlled clinical trial, 77 adults with obesity received either phentermine or placebo. All participants were provided Medifast® meal replacements, were instructed to follow the Take Shape for Life® Optimal Weight 5&1 Plan for weight loss, and received lifestyle coaching in the Habits of Health program. The Food Craving Inventory and the General Food Cravings State and Trait Questionnaires were used to measure food cravings. RESULTS: The phentermine group lost 12.1% of baseline body weight compared with 8.8% in the placebo group. Cravings for all food groups decreased in both groups; however, there was a greater reduction in cravings for fats and sweets in the phentermine group compared with the placebo group. Percent weight loss correlated significantly with reduced total food cravings (r = 0.332, P = 0.009), cravings for sweets (r = 0.412, P < 0.000), and state food cravings (r = 0.320, P = 0.007). CONCLUSIONS: Both phentermine combined with a meal replacement program and meal replacements alone significantly reduced body weight and food cravings; however, the addition of phentermine enhanced these effects.

Chlorisondamine, a sympathetic ganglionic blocker, moderates the effects of whole-body irradiation (WBI) on early host defense to a live bacterial challenge.

There is a growing consensus that long-term deficits in the brain are due to dynamic interactions between multiple neural and immune cell types. Specifically, radiation induces an inflammatory response, including changes in neuromodulatory pro- and anti-inflammatory cytokine secretion. The purpose of this study was to establish that there is sympathetic involvement in radiation-induced decrements early in in vivo immune function host defense. Female, 8-9 week-old C57BL/6J mice were exposed to whole-body irradiation (WBI). There were 8 groups with radiation (0 vs. 3 Gy protons), immune challenge (Escherichia coli) and exposure to the sympathetic ganglionic blocker, chlorisondamine (1 mg/kg weight, i.p.), as independent variables. Ten days post-irradiation, mice were inoculated with E. coli intraperitoneally and sacrificed 90-120 min later. The data suggest that radiation-induced changes in immune function may in part be mediated by the sympathetic nervous system. Briefly, we found that radiation augments the bacteria-induced inflammatory cytokine response, particularly those cytokines involved in innate immunity. However, this augmentation can be reduced by the ganglionic blockade.

Religious vs. conventional cognitive behavioral therapy for major depression in persons with chronic medical illness: a pilot randomized trial.

We examine the efficacy of conventional cognitive behavioral therapy (CCBT) versus religiously integrated CBT (RCBT) in persons with major depression and chronic medical illness. Participants were randomized to either CCBT (n = 67) or RCBT (n = 65). The intervention in both groups consisted of ten 50-minute sessions delivered remotely during 12 weeks (94% by telephone). Adherence to treatment was similar, except in more religious participants in whom adherence to RCBT was slightly greater (85.7% vs. 65.9%, p = 0.10). The intention-to-treat analysis at 12 weeks indicated no significant difference in outcome between the two groups (B = 0.33; SE, 1.80; p = 0.86). Response rates and remission rates were also similar. Overall religiosity interacted with treatment group (B = -0.10; SE, 0.05; p = 0.048), suggesting that RCBT was slightly more efficacious in the more religious participants. These preliminary findings suggest that CCBT and RCBT are equivalent treatments of major depression in persons with chronic medical illness. Efficacy, as well as adherence, may be affected by client religiosity.

Molecular mechanisms underlying ß-adrenergic receptor-mediated cross-talk between sympathetic neurons and immune cells.

Cross-talk between the sympathetic nervous system (SNS) and immune system is vital for health and well-being. Infection, tissue injury and inflammation raise firing rates of sympathetic nerves, increasing their release of norepinephrine (NE) in lymphoid organs and tissues. NE stimulation of ß2-adrenergic receptors (ARs) in immune cells activates the cAMP-protein kinase A (PKA) intracellular signaling pathway, a pathway that interfaces with other signaling pathways that regulate proliferation, differentiation, maturation and effector functions in immune cells. Immune-SNS cross-talk is required to maintain homeostasis under normal conditions, to develop an immune response of appropriate magnitude after injury or immune challenge, and subsequently restore homeostasis. Typically, ß2-AR-induced cAMP is immunosuppressive. However, many studies report actions of ß2-AR stimulation in immune cells that are inconsistent with typical cAMP-PKA signal transduction. Research during the last decade in non-immune organs, has unveiled novel alternative signaling mechanisms induced by ß2-AR activation, such as a signaling switch from cAMP-PKA to mitogen-activated protein kinase (MAPK) pathways. If alternative signaling occurs in immune cells, it may explain inconsistent findings of sympathetic regulation of immune function. Here, we review ß2-AR signaling, assess the available evidence for alternative signaling in immune cells, and provide insight into the circumstances necessary for "signal switching" in immune cells.

Hypothermia modulates cytokine responses after neonatal rat hypoxic-ischemic injury and reduces brain damage.

While hypothermia (HT) is the standard-of-care for neonates with hypoxic ischemic injury (HII), the mechanisms underlying its neuroprotective effect are poorly understood. We examined ischemic core/penumbra and cytokine/chemokine evolution in a 10-day-old rat pup model of HII. Pups were treated for 24 hr after HII with HT (32℃; n = 18) or normothermia (NT, 35℃; n = 15). Outcomes included magnetic resonance imaging (MRI), neurobehavioral testing, and brain cytokine/chemokine profiling (0, 24, 48, and 72 hr post-HII). Lesion volumes (24 hr) were reduced in HT pups (total 74%, p < .05; penumbra 68%, p < .05; core 85%, p = .19). Lesion volumes rebounded at 72 hr (48 hr post-HT) with no significant differences between NT and HT pups. HT reduced interleukin-1ß (IL-1ß) at all time points (p < .05); monocyte chemoattractant protein-1 (MCP-1) trended toward being decreased in HT pups (p = .09). The stem cell signaling molecule, stromal cell-derived factor-1 (SDF-1) was not altered by HT. Our data demonstrate that HT reduces total and penumbral lesion volumes (at 24 and 48 hr), potentially by decreasing IL-1ß without affecting SDF-1. Disassociation between the increasing trend in HII volumes from 48 to 72 hr post-HII when IL-1ß levels remained low suggests that after rewarming, mechanisms unrelated to IL-1ß expression are likely to contribute to this delayed increase in injury. Additional studies should be considered to determine what these mechanisms might be and also to explore whether extending the duration or degree of HT might ameliorate this delayed increase in injury.

Religious involvement is associated with greater purpose, optimism, generosity and gratitude in persons with major depression and chronic medical illness.

OBJECTIVE: Religious involvement may help individuals with chronic medical illness cope better with physical disability and other life changes. We examine the relationships between religiosity, depressive symptoms, and positive emotions in persons with major depression and chronic illness. METHODS: 129 persons who were at least somewhat religious/spiritual were recruited into a clinical trial to evaluate the effectiveness of religious vs. secular cognitive behavioral therapy. Reported here are the relationships at baseline between religious involvement and depressive symptoms, purpose in life, optimism, generosity, and gratefulness using standard measures. RESULTS: Although religiosity was unrelated to depressive symptoms (F=0.96, p=0.43) and did not buffer the disability-depression relationship (B=-1.56, SE 2.90, p=0.59), strong relationships were found between religious indicators and greater purpose, optimism, generosity, and gratefulness (F=7.08, p<0.0001). CONCLUSIONS: Although unrelated to depressive symptoms in the setting of major depression and chronic medical illness, higher religious involvement is associated with positive emotions, a finding which may influence the course of depression over time.

Targeting α- and ß-Adrenergic Receptors Differentially Shifts Th1, Th2, and Inflammatory Cytokine Profiles in Immune Organs to Attenuate Adjuvant Arthritis.

The sympathetic nervous system (SNS) regulates host defense responses and restores homeostasis. SNS-immune regulation is altered in rheumatoid arthritis (RA) and rodent models of RA, characterized by nerve remodeling in immune organs and defective adrenergic receptor (AR) signaling to immune cell targets. The SNS typically promotes or suppresses inflammation via α- and ß2-AR activation, respectively, and indirectly drives humoral immunity by blocking Th1 cytokine secretion. Here, we investigate how ß2-AR stimulation and/or α-AR blockade at disease onset affects disease pathology and cytokine profiles in relevant immune organs from male Lewis rats with adjuvant-induced arthritis (AA). Rats challenged to induce AA were treated with terbutaline (TERB), a ß2-AR agonist (600 µg/kg/day) and/or phentolamine (PHEN), an α-AR antagonist (5.0 mg/kg/day) or vehicle from disease onset through severe disease. We report that in spleen, mesenteric (MLN) and draining lymph node (DLN) cells, TERB reduces proliferation, an effect independent of IL-2. TERB also fails to shift T helper (Th) cytokines from a Th1 to Th2 profile in spleen and MLN (no effect on IFN-γ) and DLN (greater IFN-γ) cells. In splenocytes, TERB, PHEN, and co-treatment (PT) promotes an anti-inflammatory profile (greater IL-10) and lowers TNF-α (PT only). In DLN cells, drug treatments do not affect inflammatory profiles, except PT, which raised IL-10. In MLN cells, TERB or PHEN lowers MLN cell secretion of TNF-α or IL-10, respectively. Collectively, our findings indicate disrupted ß2-AR, but not α-AR signaling in AA. Aberrant ß2-AR signaling consequently derails the sympathetic regulation of lymphocyte expansion, Th cell differentiation, and inflammation in the spleen, DLNs and MLs that is required for immune system homeostasis. Importantly, this study provides potential mechanisms through which reestablished balance between α- and ß2-AR function in the immune system ameliorates inflammation and joint destruction in AA.