Mental health and social connection among older lesbian and bisexual women.

OBJECTIVE: To assess differences in psychosocial and mental health outcomes between older lesbian and bisexual women compared to heterosexual women. DESIGN: Cross sectional study. SETTING: The study was carried out in the California Teachers Study, a prospective cohort study. PARTICIPANTS: Self-identified heterosexual (n = 35,846), lesbian (n = 710), and bisexual (n = 253) women 50 years of age and older were enrolled. MEASUREMENTS: Validated questionnaires were used to measure social connection, overall happiness, and depression. Logistic regression modeling was used to estimate odds ratios (OR) and 95% confidence intervals (CI) comparing lesbian and bisexual women separately to heterosexual women in relation to psychosocial and mental health outcomes. RESULTS: After controlling for age and marital status, older bisexual women were significantly more likely to report lack of companionship (OR = 2.00; 95% CI, 1.30-3.12) and feeling left out (OR = 2.33; 95% CI, 1.36-3.97) compared to older heterosexual women. The odds of reporting feeling isolated from others was significantly higher in lesbian (OR = 1.56; 95% CI, 1.06-2.30) and bisexual women (OR = 2.30; 95% CI, 1.37-3.87) than in heterosexual women. The OR (95% CI) for reporting not being very happy overall was 1.96 (CI, 1.09-3.52) in bisexual women and 1.40 (0.92-2.14) in lesbian women compared to heterosexual women. The likelihood of reporting diagnosed depression was significantly higher in lesbian women (OR = 1.65; 95% CI, 1.38-1.97) and bisexual women (OR = 2.21; 95% CI, 1.67-2.93) compared to heterosexual women. CONCLUSION: Inclusion of lesbian and bisexual women in aging research is essential to understand their unique mental and other health needs, including those specific to bisexual women.

A longitudinal study of cannabis use and risk for cognitive and functional decline among older adults with HIV.

Cannabis use is rapidly increasing among older adults in the United States, in part to treat symptoms of common health conditions (e.g., chronic pain, sleep problems). Longitudinal studies of cannabis use and cognitive decline in aging populations living with chronic disease are lacking. We examined different levels of cannabis use and cognitive and everyday function over time among 297 older adults with HIV (ages 50-84 at baseline). Participants were classified based on average cannabis use: frequent (> weekly) (n = 23), occasional (≤ weekly) (n = 83), and non-cannabis users (n=191) and were followed longitudinally for up to 10 years (average years of follow-up = 3.9). Multi-level models examined the effects of average and recent cannabis use on global cognition, global cognitive decline, and functional independence. Occasional cannabis users showed better global cognitive performance overall compared to non-cannabis users. Rates of cognitive decline and functional problems did not vary by average cannabis use. Recent cannabis use was linked to worse cognition at study visits when participants had THC+ urine toxicology-this short-term decrement in cognition was driven by worse memory and did not extend to reports of functional declines. Occasional (≤ weekly) cannabis use was associated with better global cognition over time in older adults with HIV, a group vulnerable to chronic inflammation and cognitive impairment. Recent THC exposure may have a temporary adverse impact on memory. To inform safe and efficacious medical cannabis use, the effects of specific cannabinoid doses on cognition and biological mechanisms must be investigated in older adults.

RESUMEN: El consumo de cannabis está aumentando rápidamente entre los adultos mayores en los Estados Unidos, en parte para tratar síntomas de afecciones de salud comunes (p. ej. dolor crónico, problemas de dormir). Actualmente, hay pocos estudios longitudinales sobre el consumo de cannabis y el deterioro cognitivo en poblaciones que envejecen y viven con enfermedades crónicas. Examinamos diferentes niveles del consumo de cannabis y funciones cognitivas a lo largo del tiempo entre 297 adultos mayores con VIH (de 50 a 84 años al principio de la investigación). Los participantes se clasificaron según el consumo promedio de cannabis: consumidores de cannabis frecuentes (> semanal) (n = 23) ocasionales (≤ semanal) (n = 83), y no consumidores de cannabis (n=191) fueron seguidos longitudinalmente hasta por 10 años (promedio = 3,9 años). Los modelos multinivel investigaron los efectos del consumo promedio y reciente de cannabis en la cognición global, el deterioro cognitivo global, y la independencia funcional. Los consumidores ocasionales de cannabis mostraron un mejor rendimiento cognitivo global en comparación con los no consumidores. El nivel de deterioro cognitivo y problemas funcionales no estuvieron asociado con el uso de cannabis. El consumo reciente de cannabis se vinculó con una peor cognición en las visitas del estudio cuando los participantes tenían toxicología de orina de THC positivo­esta disminución a corto plazo de la cognición se debió a una peor memoria, pero no se extendió a los informes de deterioros funcionales. El consumo ocasional (≤ semanal) de cannabis se asoció con una mejor cognición global a lo largo del tiempo en adultos mayores con VIH, un grupo susceptible a la inflamación crónica y la disfunción cognitiva. La exposición reciente al THC puede tener un impacto negativo temporal en la memoria. Los efectos de dosis específicas de cannabinoides en la cognición y sus mecanismos de acción biológicos deben ser investigados en personas mayores con el fin de informar el uso seguro y eficaz del cannabis medicinal.

Tai Chi versus health education as a frailty intervention for community-dwelling older adults with hypertension.

BACKGROUND: Frailty is associated with poor outcomes among older adults with hypertension and complicates its pharmacological management. Here, we assessed whether 12-weeks of instructor-guided, group Tai Chi (TC) practice improved frailty relative to Healthy Aging Practice-centered Education (HAP-E) classes in older adults with hypertension. METHODS: Secondary analysis of a randomized controlled trial in San Diego County, USA, of 167 community-dwelling individuals aged ≥ 60 yrs (70% female; 72.1 ± 7.5 yrs), defined as non-frail (66%) or frail (34%) based on 53-item deficit accumulation frailty index (FI). Linear mixed-effects models were used to assess pre-to-post intervention differences in FI and logistic regression to explore differential odds of clinically meaningful FI change. RESULTS: One hundred thirty-one participants completed post-intervention assessments. Frailty decreased pre-to-post intervention in the TC (ΔFI = - 0.016, d = - 0.39, - 0.75 to - 0.03), but not the HAP-E arm (ΔFI = - 0.009, d = - 0.13, - 0.52-0.27), despite no significant group differences between the TC and HAP-E arms (d = - 0.11, - 0.46-0.23). Furthermore, greater odds of improved FI were observed for frail participants in the TC (OR = 3.84, 1.14-14.9), but not the HAP-E (OR = 1.34, 0.39-4.56) arm. Subgroup analysis indicated treatment effects in TC were attributed to frail participants (frail: ΔFI = - 0.035, d = - 0.68, -1.26 to - 0.08; non-frail: ΔFI = - 0.005, d = - 0.19, - 0.59-0.22), which was not the case in the HAP-E arm (frail: ΔFI = - 0.017, d = - 0.23, - 0.81-0.35; non-frail: ΔFI = - 0.003, d = - 0.07, - 0.47-0.33). Frail participants were no more likely to drop-out of the study than non-frail (71% vs. 69% retained). CONCLUSIONS: Twelve weeks of twice-weekly guided TC practice was well-tolerated, associated with decreases in frailty, and increased odds of clinically meaningful FI improvement at post-intervention.

Tai chi or health education for older adults with hypertension: effects on mental health and psychological resilience to COVID-19.

OBJECTIVE: To compare the effectiveness of 12 weeks of community-based, in-person, group Tai Chi (TC) and Health Education (HAP-E) in improving health and wellbeing in older adults with hypertension and in promoting psychological resilience during COVID-19. METHODS: A 12-week randomized controlled trial (RCT) in San Diego County, USA. Self-reported depressive symptoms, anxiety, sleep disturbances, gratitude, resilience, mental and physical health were assessed in-person pre- and post-intervention, and by long-term follow-up surveys during COVID-19. Linear mixed-effects models were used to assess study arm differences over time and logistic regression to identify predictors of positive intervention response. RESULTS: Of 182 randomized participants (72.6 ± 7.9 yrs; 72% female), 131 completed the intervention. Modest improvements in health and wellbeing occurred post-intervention in both arms (Cohen's d: TC = 0.38, 95% CI: 0.25-0.51; HAP-E = 0.24, 0.11-0.37), though positive intervention responses were more than twice as likely in TC (OR = 2.29, 1.07-4.57). Younger age, higher anxiety, and poorer mental health at baseline predicted greater odds of response. Small declines in health and wellbeing were reported at the first COVID-19 follow-up, with smaller declines in the TC arm (Cohen's d: TC = -0.15, -0.31-0.00; HAP-E = -0.34, -0.49 to -0.19). Health and wellbeing stabilized at the second COVID-19 follow-up. Most participants (>70%) reported that the interventions benefitted their health and wellbeing during COVID-19. CONCLUSION: TC and HAP-E improved health and wellbeing, though TC conferred greater odds of an improved mental health response. Declines in health and wellbeing were observed at pandemic follow-up, with smaller declines in the TC arm, suggesting increased resilience.

Salivary bacterial signatures in depression-obesity comorbidity are associated with neurotransmitters and neuroactive dipeptides.

BACKGROUND: Depression and obesity are highly prevalent, often co-occurring conditions marked by inflammation. Microbiome perturbations are implicated in obesity-inflammation-depression interrelationships, but how the microbiome mechanistically contributes to pathology remains unclear. Metabolomic investigations into microbial neuroactive metabolites may offer mechanistic insights into host-microbe interactions. Using 16S sequencing and untargeted mass spectrometry of saliva, and blood monocyte inflammation regulation assays, we identified key microbes, metabolites and host inflammation in association with depressive symptomatology, obesity, and depressive symptomatology-obesity comorbidity. RESULTS: Gram-negative bacteria with inflammation potential were enriched relative to Gram-positive bacteria in comorbid obesity-depression, supporting the inflammation-oral microbiome link in obesity-depression interrelationships. Oral microbiome was more highly predictive of depressive symptomatology-obesity co-occurrences than of obesity or depressive symptomatology independently, suggesting specific microbial signatures associated with obesity-depression co-occurrences. Mass spectrometry analysis revealed significant changes in levels of signaling molecules of microbiota, microbial or dietary derived signaling peptides and aromatic amino acids among depressive symptomatology, obesity and comorbid obesity-depression. Furthermore, integration of the microbiome and metabolomics data revealed that key oral microbes, many previously shown to have neuroactive potential, co-occurred with potential neuropeptides and biosynthetic precursors of the neurotransmitters dopamine, epinephrine and serotonin. CONCLUSIONS: Together, our findings offer novel insights into oral microbial-brain connection and potential neuroactive metabolites involved.

Systemic Inflammation and Cognitive Decrements in Patients With Stage B Heart Failure.

OBJECTIVE: This study aimed to investigate the role of systemic inflammation in reduced cognitive functioning in patients with early-stage heart failure (HF) while determining associations with other cardiovascular risk factors. METHODS: Patients with stage B HF (n = 270; mean [standard deviation] age = 66.1 [10.1] years) were examined cross-sectionally for relationships among cardiovascular disease (CVD) and psychological risk factors, C-reactive protein (CRP), and Montreal Cognitive Assessment (MoCA) scores. A subsample (n = 83) at high risk for stage C HF (B-type natriuretic peptide levels ≥65 pg/ml) were followed up for 12 months for relationships between CRP levels and cognitive function. RESULTS: Baseline smoking (χ2 = 6.33), unmarried (χ2 = 12.0), hypertension (χ2 = 5.72), greater body mass index (d = 0.45), and physical fatigue (d = 0.25) were related to higher CRP levels (p values < .05). Cross-sectionally, CRP levels were negatively related to MoCA scores, beyond CVD (ΔR2 = 0.022, ß = -0.170, p < .010) and psychological risk factors (ΔR2 = 0.016, ß = 0.145, p < .027), and related to mild cognitive impairment criteria (odds ratio = 1.35, 95% confidence interval [CI] = 1.00-1.81, p = .046). Across 12 months, B-type natriuretic peptide high-risk patients with CRP levels ≥3 mg/L had lower MoCA scores (23.6; 95% CI = 22.4-24.8) than did patients with CRP levels <3 mg/L (25.4; 95% CI = 24.4-26.5; p = .024). CONCLUSIONS: Patients with stage B HF and heightened CRP levels had greater cognitive impairment at baseline and follow-up, independent of CVD and potentially psychological risk factors. Low-grade systemic inflammation may be one mechanism involved in cognitive dysfunction at early stages of HF.

Daily Cannabis Use is Associated With Lower CNS Inflammation in People With HIV.

OBJECTIVE: Recent cannabis exposure has been associated with lower rates of neurocognitive impairment in people with HIV (PWH). Cannabis's anti-inflammatory properties may underlie this relationship by reducing chronic neuroinflammation in PWH. This study examined relations between cannabis use and inflammatory biomarkers in cerebrospinal fluid (CSF) and plasma, and cognitive correlates of these biomarkers within a community-based sample of PWH. METHODS: 263 individuals were categorized into four groups: HIV- non-cannabis users (n = 65), HIV+ non-cannabis users (n = 105), HIV+ moderate cannabis users (n = 62), and HIV+ daily cannabis users (n = 31). Differences in pro-inflammatory biomarkers (IL-6, MCP-1/CCL2, IP-10/CXCL10, sCD14, sTNFR-II, TNF-α) by study group were determined by Kruskal-Wallis tests. Multivariable linear regressions examined relationships between biomarkers and seven cognitive domains, adjusting for age, sex/gender, race, education, and current CD4 count. RESULTS: HIV+ daily cannabis users showed lower MCP-1 and IP-10 levels in CSF compared to HIV+ non-cannabis users (p = .015; p = .039) and were similar to HIV- non-cannabis users. Plasma biomarkers showed no differences by cannabis use. Among PWH, lower CSF MCP-1 and lower CSF IP-10 were associated with better learning performance (all ps < .05). CONCLUSIONS: Current daily cannabis use was associated with lower levels of pro-inflammatory chemokines implicated in HIV pathogenesis and these chemokines were linked to the cognitive domain of learning which is commonly impaired in PWH. Cannabinoid-related reductions of MCP-1 and IP-10, if confirmed, suggest a role for medicinal cannabis in the mitigation of persistent inflammation and cognitive impacts of HIV.

Are we facing a crashing wave of neuropsychiatric sequelae of COVID-19? Neuropsychiatric symptoms and potential immunologic mechanisms.

The coronavirus disease 19 (COVID-19) pandemic is a significant psychological stressor in addition to its tremendous impact on every facet of individuals' lives and organizations in virtually all social and economic sectors worldwide. Fear of illness and uncertainty about the future precipitate anxiety- and stress-related disorders, and several groups have rightfully called for the creation and dissemination of robust mental health screening and treatment programs for the general public and front-line healthcare workers. However, in addition to pandemic-associated psychological distress, the direct effects of the virus itself (several acute respiratory syndrome coronavirus; SARS-CoV-2), and the subsequent host immunologic response, on the human central nervous system (CNS) and related outcomes are unknown. We discuss currently available evidence of COVID-19 related neuropsychiatric sequelae while drawing parallels to past viral pandemic-related outcomes. Past pandemics have demonstrated that diverse types of neuropsychiatric symptoms, such as encephalopathy, mood changes, psychosis, neuromuscular dysfunction, or demyelinating processes, may accompany acute viral infection, or may follow infection by weeks, months, or longer in recovered patients. The potential mechanisms are also discussed, including viral and immunological underpinnings. Therefore, prospective neuropsychiatric monitoring of individuals exposed to SARS-CoV-2 at various points in the life course, as well as their neuroimmune status, are needed to fully understand the long-term impact of COVID-19, and to establish a framework for integrating psychoneuroimmunology into epidemiologic studies of pandemics.

Self-reported sleep disturbances are associated with poorer cognitive performance in older adults with hypertension: a multi-parameter risk factor investigation.

OBJECTIVES: Given the evidence of multi-parameter risk factors in shaping cognitive outcomes in aging, including sleep, inflammation, cardiometabolism, and mood disorders, multidimensional investigations of their impact on cognition are warranted. We sought to determine the extent to which self-reported sleep disturbances, metabolic syndrome (MetS) factors, cellular inflammation, depressive symptomatology, and diminished physical mobility were associated with cognitive impairment and poorer cognitive performance. DESIGN: This is a cross-sectional study. SETTING: Participants with elevated, well-controlled blood pressure were recruited from the local community for a Tai Chi and healthy-aging intervention study. PARTICIPANTS: One hundred forty-five older adults (72.7 ± 7.9 years old; 66% female), 54 (37%) with evidence of cognitive impairment (CI) based on Montreal Cognitive Assessment (MoCA) score ≤24, underwent medical, psychological, and mood assessments. MEASUREMENTS: CI and cognitive domain performance were assessed using the MoCA. Univariate correlations were computed to determine relationships between risk factors and cognitive outcomes. Bootstrapped logistic regression was used to determine significant predictors of CI risk and linear regression to explore cognitive domains affected by risk factors. RESULTS: The CI group were slower on the mobility task, satisfied more MetS criteria, and reported poorer sleep than normocognitive individuals (all p < 0.05). Multivariate logistic regression indicated that sleep disturbances, but no other risk factors, predicted increased risk of evidence of CI (OR = 2.00, 95% CI: 1.26-4.87, 99% CI: 1.08-7.48). Further examination of MoCA cognitive subdomains revealed that sleep disturbances predicted poorer executive function (ß = -0.26, 95% CI: -0.51 to -0.06, 99% CI: -0.61 to -0.02), with lesser effects on visuospatial performance (ß = -0.20, 95% CI: -0.35 to -0.02, 99% CI: -0.39 to 0.03), and memory (ß = -0.29, 95% CI: -0.66 to -0.01, 99% CI: -0.76 to 0.08). CONCLUSIONS: Our results indicate that the deleterious impact of self-reported sleep disturbances on cognitive performance was prominent over other risk factors and illustrate the importance of clinician evaluation of sleep in patients with or at risk of diminished cognitive performance. Future, longitudinal studies implementing a comprehensive neuropsychological battery and objective sleep measurement are warranted to further explore these associations.

Sex-specific roles of cellular inflammation and cardiometabolism in obesity-associated depressive symptomatology.

BACKGROUND: Obesity and depression are complex conditions with stronger comorbid relationships among women than men. Inflammation and cardiometabolic dysfunction are likely mechanistic candidates for increased depression risk, and their prevalence differs by sex. Whether these relationships extend to depressive symptoms is poorly understood. Therefore, we analyzed sex in associations between inflammation and metabolic syndrome (MetS) criteria on depressive symptomatology. Specifically, we examined whether sex positively moderates the relationship between depressive symptoms and inflammation among women, and whether MetS has parallel effects among men. METHODS: Depressive symptoms, MetS, and inflammation were assessed in 129 otherwise healthy adults. Depressive symptoms were assessed using Beck Depression Inventory (BDI-Ia). Monocyte inflammation regulation (BARIC) was quantified using flow cytometry measurement of TNF-α suppression by ß-agonist. Moderation effects of sex on associations between BARIC, MetS criteria, and BDI were estimated using two-way ANOVA and linear regression, adjusting for BMI, and by sex subgroup analyses. RESULTS: Obese individuals reported more depressive symptoms. Sex did not formally moderate this relationship, though BDI scores tended to differ by BMI among women, but not men, in subgroup analysis. Poorer inflammation control and higher MetS criteria were correlated with somatic depressive symptoms. Sex moderated associations between MetS criteria and somatic symptoms; among men, MetS criteria predicted somatic symptoms, not among women. Subgroup analysis further indicated that poorer inflammation control tended to be associated with higher somatic symptoms in women. CONCLUSIONS: These results indicate that obesity-related inflammation and MetS factors have sex-specific effects on depressive symptoms in a non-clinical population. Although pathophysiological mechanisms underlying sex differences remain to be elucidated, our findings suggest that distinct vulnerabilities to depressive symptoms exist between women and men, and highlight the need to consider sex as a key biological variable in obesity-depression relationships. Future clinical studies on comorbid obesity and depression should account for sex, which may optimize therapeutic strategies.

Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via ß2-adrenergic activation.

Regular exercise is shown to exert anti-inflammatory effects, yet the effects of acute exercise on cellular inflammatory responses and its mechanisms remain unclear. We tested the hypothesis that sympathoadrenergic activation during a single bout of exercise has a suppressive effect on monocytic cytokine production mediated by ß2 adrenergic receptors (AR). We investigated the effects of 20-min moderate (65-70% VO2 peak) exercise-induced catecholamine production on LPS-stimulated TNF production by monocytes in 47 healthy volunteers and determined AR subtypes involved. We also examined the effects of ß-agonist isoproterenol and endogenous ß- and α-agonists epinephrine and norepinephrine, and receptor-subtype-specific ß- and α-antagonists on TNF production in a series of in vitro investigations. LPS-stimulated TNF production by peripheral blood monocytes was determined intracellularly by flow cytometry, using an intracellular protein transport inhibitor. Percent TNF-producing monocytes and per-cell TNF production with and without LPS was suppressed by exercise with moderate to large effects, which was reversed by a ß2-AR antagonist in spite that plasma TNF levels did not change. This inhibitory response in TNF production by exercise was mirrored by ß-AR agonists in an agonist-specific and dose-dependent manner in vitro: similar isoproterenol (EC50=2.1-4.7×10-10M) and epinephrine (EC50=4.4-10×10-10M) potency and higher norepinephrine concentrations (EC50=2.6-4.3×10-8M) needed for the effects. Importantly, epinephrine levels observed during acute exercise in vivo significantly inhibited TNF production in vitro. The inhibitory effect of the AR agonists was abolished by ß2-, but not by ß1- or α-AR blockers. We conclude that the downregulation of monocytic TNF production during acute exercise is mediated by elevated epinephrine levels through ß2-ARs. Decreased inflammatory responses during acute exercise may protect against chronic conditions with low-grade inflammation.

Inflammation in Schizophrenia: Cytokine Levels and Their Relationships to Demographic and Clinical Variables.

OBJECTIVE: Inflammation may play a role in the accelerated physical aging reported in schizophrenia, though biomarker findings and associations with demographic and clinical factors are inconsistent. METHODS: In a cross-sectional, case-control design, 95 outpatients with schizophrenia (mean age ± SD: 48.1 ± 10.2 years) and 95 demographically comparable healthy comparison subjects (HCs) (mean age ± SD: 48.1 ± 12.1 years) were studied. Sociodemographic and clinical data were collected, and plasma levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interferon-γ (IFN-γ) were assayed. The authors compared cytokine levels, examined demographic and clinical associations, and adjusted for relevant variables with linear models. RESULTS: Individuals with schizophrenia had higher levels of TNF-α and IL-6 but not IFN-γ than HCs. Age was not related to cytokine levels, and age relationships did not differ between diagnostic groups. Women had higher levels of IL-6. TNF-α and IL-6 levels were significantly correlated with depressive symptoms, and adjustment for depression reduced the group effect for both. Within the HCs, TNF-α levels were associated with physical comorbidity and body mass index. IL-6 levels were significantly correlated with body mass index and within schizophrenia patients, with worse mental and physical well-being. Accounting for physical morbidity and mental well-being reduced group differences in TNF-α and IL-6 levels, respectively. Worse positive symptoms were associated with higher IL-6 levels. CONCLUSION: Higher TNF-α and IL-6 levels in schizophrenia patients were associated with depression, physical comorbidity, and mental well-being. Further longitudinal studies are warranted to assess inflammation as a potential treatment target for a subgroup of schizophrenia.

Role of the immune system in HIV-associated neuroinflammation and neurocognitive implications.

Individuals living with HIV who are optimally treated with combination antiretroviral therapy (cART) can now lead an extended life. In spite of this remarkable survival benefit from viral suppression achieved by cART in peripheral blood, the rate of mild to moderate cognitive impairment remains high. A cognitive decline that includes impairments in attention, learning and executive function is accompanied by increased rates of mood disorders that together adversely impact the daily life of those with chronic HIV infection. The evidence is clear that cells in the brain are infected with HIV that has crossed the blood-brain barrier both as cell-free virus and within infected monocytes and T cells. Viral proteins that circulate in blood can induce brain endothelial cells to release cytokines, invoking another source of neuroinflammation. The difficulty of efficient delivery of cART to the central nervous system (CNS) contributes to elevated viral load in the CNS, resulting in a persistent HIV-associated neurocognitive disorders (HAND). The pathogenesis of HAND is multifaceted, and mounting evidence indicates that immune cells play a major role. HIV-infected monocytes and T cells not only infect brain resident cells upon migration into the CNS but also produce proinflammatory cytokines such as TNF and IL-1ß, which in turn, further activate microglia and astrocytes. These activated brain resident cells, along with perivascular macrophages, are the main contributors to neuroinflammation in HIV infection and release neurotoxic factors such as excitatory amino acids and inflammatory mediators, resulting in neuronal dysfunction and death. Cytokines, which are elevated in the blood of patients with HIV infection, may also contribute to brain inflammation by entering the brain from the blood. Host factors such as aging and co-morbid conditions such as cytomegalovirus co-infection and vascular pathology are important factors that affect the HIV-host immune interactions in HAND pathogenesis. By these diverse mechanisms, HIV-1 induces a neuroinflammatory response that is likely to be a major contributor to the cognitive and behavior changes seen in HIV infection.

Beta-adrenergic receptor mediated inflammation control by monocytes is associated with blood pressure and risk factors for cardiovascular disease.

Overwhelming data indicate that individuals with even mildly elevated blood pressure (BP) are at great risk for developing clinical hypertension and future cardiovascular disease (CVD). There remains a lack of consensus regarding treatment strategies for mildly elevated BP, termed prehypertension, and the knowledge of pathophysiology and mechanisms of its clinical outcomes remains limited. Our primary aim was to investigate ßAR-mediated inflammation control (BARIC) responses of blood monocytes to isoproterenol (Iso) in relation to BP and CVD risk factors, including obesity, depressive mood, fasting glucose, triglycerides, and cholesterol levels in the 64 prehypertensive compared to 84 individuals with normal BP. BARIC was determined by measuring the degree of inhibition in lipopolysaccharides-stimulated monocytic intracellular TNF production by ex vivo Iso treatment (10(-8)M). Depressive mood was assessed by Beck Depression Inventory (BDI). Fasting metabolic and lipid panels were assessed, and plasma levels of inflammatory cytokines TNF, IL-1ß, IL-6 were measured in a subset to confirm proinflammatory state of prehypertensive participants. Prehypertensive participants were older, heavier, included more men, and presented higher levels of fasting glucose, triglycerides, cholesterol, and plasma TNF compared to normotensive participants (p's<.05). BARIC was significantly attenuated in the prehypertensive compared to normotensive group (p<.05). BARIC was negatively associated with systolic BP, diastolic BP, age, BMI, fasting glucose, triglycerides, total and low density cholesterol levels, and somatic depressive symptoms in all participants (p's<.0001 to .05). However, among the prehypertensive individuals BARIC was positively associated with SBP even after controlling for the covariates (age, gender, race, BMI, glucose and lipid panel, somatic BDI scores) (p<.05). This differing nature of the BARIC-SBP relationship between the two BP groups may be attributed to moderating factors such as cardiorespiratory fitness or depressive symptoms that could not be clearly deciphered in this current study. Nonetheless, our findings indicate the associations between inflammation dysregulation mediated by sympathoadrenal activation and BP that is observable even among individuals with normal to mildly elevated BP. BARIC may be a useful and sensitive indicator of elevated risk for vascular inflammatory disease that can be detected even at lower BP levels, especially given its associations with traditional CVD risk factors and the critical role of monocytes in atherogenic processes.

Progenitor cells are mobilized by acute psychological stress but not beta-adrenergic receptor agonist infusion.

OBJECTIVES: Stimuli that activate the sympathetic nervous system, such as acute psychological stress, rapidly invoke a robust mobilization of lymphocytes into the circulation. Experimental animal studies suggest that bone marrow-derived progenitor cells (PCs) also mobilize in response to sympathetic stimulation. Here we tested the effects of acute psychological stress and brief pharmacological ß-adrenergic (ßAR) stimulation on peripheral PC numbers in humans. METHODS: In two studies, we investigated PC mobilization in response to an acute speech task (n=26) and ßAR-agonist (isoproterenol) infusion (n=20). A subset of 8 participants also underwent the infusion protocol with concomitant administration of the ßAR-antagonist propranolol. Flow cytometry was used to enumerate lymphocyte subsets, total progenitor cells, total haematopoietic stem cells (HSC), early HSC (multi-lineage potential), late HSC (lineage committed), and endothelial PCs (EPCs). RESULTS: Both psychological stress and ßAR-agonist infusion caused the expected mobilization of total monocytes and lymphocytes and CD8(+) T lymphocytes. Psychological stress also induced a modest, but significant, increase in total PCs, HSCs, and EPC numbers in peripheral blood. However, infusion of a ßAR-agonist did not result in a significant change in circulating PCs. CONCLUSION: PCs are rapidly mobilized by psychological stress via mechanisms independent of ßAR-stimulation, although the findings do not exclude ßAR-stimulation as a possible cofactor. Considering the clinical and physiological relevance, further research into the mechanisms involved in stress-induced PC mobilization seems warranted.

Leukocyte ß-adrenergic receptor sensitivity and depression severity in patients with heart failure.

OBJECTIVES: Clinical outcomes are worse for patients with heart failure (HF) and elevated depression symptoms. Depression-related sympathoimmune dysregulation may be one mechanism leading to poorer HF prognosis. Sympathetically mediated adrenergic activity is known to regulate immune activity via ß-adrenergic receptors (ß-ARs). However, studies show conflicting relationships between leukocyte ß-AR sensitivity and depression symptoms. The aim of this study was to determine in patients with HF the relationship of leukocyte ß-AR sensitivity with two diverse measures of depression, self-report questionnaire versus clinical diagnostic interview. METHODS: Patients with HF (N = 73, mean [standard deviation] age = 56.3 [13.0]) completed the Beck Depression Inventory-1A and a modified Structured Clinical Interview for the DSM-IV. Leukocyte ß-AR sensitivity was determined from isoproterenol-stimulated cyclic adenosine monophosphate levels; plasma norepinephrine and epinephrine were also assessed. RESULTS: Patients with major depression determined by Structured Clinical Interview for the DSM-IV had significantly higher ß-AR sensitivity than did nondepressed patients (F(6,72) = 9.27, p = .003, η = 0.12). The Beck Depression Inventory-1A revealed a more complex relationship. Minimal, mild, and moderate-to-severe depression symptom groups had significant differences in ß-AR sensitivity (F(7,72) = 7.03, p = .002, η = 0.18); mild symptoms were associated with reduced ß-AR sensitivity and moderate-to-severe symptoms with higher ß-AR sensitivity compared with patients with minimal depressive symptoms. CONCLUSIONS: Clinical depression was associated with elevated ß-AR sensitivity in patients with HF. By deconstructing depression measurements, a greater depth of information may be garnered to potentially reveal subtypes of depression symptoms and their relation to ß-AR sensitivity.

Benefit of physical fitness against inflammation in obesity: role of beta adrenergic receptors.

Evidence shows that both poor physical fitness and obesity are linked to low-grade inflammation and inflammatory diseases. However, their relative roles on inflammation and underlying mechanisms remain unclear. Given the inhibitory effect of catecholamines on inflammatory cytokine production, we speculated that compromised responsiveness of immune cells' beta adrenergic receptors (ß-ARs) to agonists may be associated with constitutively elevated levels of inflammatory cytokines. We examined circulating levels of inflammatory cytokines TNF, IL-1ß, IL-6 and ß-AR sensitivity of, 70 overweight or obese compared to 26 normal-weight, otherwise healthy individuals in order to investigate the associations among obesity, physical fitness, and low-grade inflammation and to examine the role of ß-ARs in these relationships. Cardiorespiratory fitness was determined by VO2peak (ml/kg/min) via a treadmill exercise. Beta-AR sensitivity was evaluated by measuring the degree of inhibition in lipopolysaccharides-stimulated monocytic intracellular TNF production by isoproterenol. In all participants, BMI, which was initially a predictor of IL-1ß and IL-6 levels independent of demographic characteristics, no longer significantly predicted them after controlling for fitness levels. Among the overweight or obese participants, greater cardiorespiratory fitness was a strong predictor of lower levels of TNF and IL-1ß after controlling for the covariates. When ß-AR sensitivity was controlled for, however, fitness was no longer a significant predictor of those cytokines. Monocytic ß-AR sensitivity was negatively associated with inflammatory marker levels and diminished in obese individuals; however, when fitness was controlled for, the significant weight group differences in ß-AR sensitivity disappeared. Our findings indicate that better cardiorespiratory fitness protects against obesity-related low-grade inflammation and ß-AR desensitization. Given the significance of ß-AR function in pathogenesis of various diseases, clinical implications of its role in the fitness-inflammation association among the obese are profound.

Measures of adiposity predict interleukin-6 responses to repeated psychosocial stress.

OBJECTIVE: Overweight and obese individuals, who comprise approximately two-thirds of the U.S. population, are at increased risk for developing a range of diseases. This increased risk may be due in part to maladaptive stress responses within this group, including heightened low-grade inflammation and HPA axis non-habituation. In this study we tested the relationship between adiposity, plasma interleukin-6 (IL-6) and HPA axis responses to repeated stress. METHODS: Sixty-seven healthy participants were exposed to the Trier Social Stress Test (TSST) on two consecutive days. We collected saliva for cortisol measurements at baseline and at 1, 10, 30, 60 and 120min post-TSST, and blood for plasma IL-6 measurements at baseline and 30 and 120min post-TSST. RESULTS: Stress exposure induced significant increases of cortisol and IL-6 on both days (cortisol: F=38, p<0.001; IL-6: F=90.8; p<0.001), and repeated exposure was related with cortisol habituation (F=8.2; p<0.001) and IL-6 sensitization (F=5.2; p=0.022). BMI and body fat were related with higher cortisol responses to repeated stress (BMI: beta=0.34; p=0.014; body fat: beta=0.29; p=0.045), and with higher IL-6 responses to repeated stress (BMI: beta=0.27, p=0.044; body fat: beta=0.37; p=0.006). CONCLUSIONS: Taken together, individuals with higher measures of adiposity showed less efficient HPA axis habituation as well as sensitization of IL-6 responses to repeated acute stress. These findings point to maladaptive stress response patterns in overweight humans, which, through exposure to higher levels of inflammatory mediators, might partially explain diseases related with overweight and/or obesity.