Baseline serum brain-derived neurotrophic factor association with future cognition in community-dwelling older adults undergoing annual memory screening.

OBJECTIVES: It has been shown that peripheral measures of brain-derived neurotrophic factor (BNDF), an important neurotrophin instrumental to the biology of learning, may contribute to predicting cognitive decline. However, the two primary forms of BDNF, mature (mBDNF) and pro (proBDNF), and how they contribute to cognition longitudinally has not been well studied. METHODS: Eighty-two older adults (average age 72.2 ± 6.4 years) provided blood samples at two time points separated on average by 4.2 years while participating in an annual memory screening that included the MoCA (Montreal Cognitive Assessment) and GDS (Geriatric Depression Scale). Both mBDNF and proBDNF from serum were quantified at each time point. Whole blood samples were genotyped for APOE and BDNF Val66Met. RESULTS: Using logistic regression analysis controlling for age, sex, baseline MoCA score, APOE, and BDNF, higher baseline mBDNF was associated with subjects whose screening score was near maximum or maximum (as defined by MoCA score of 29 or 30) at the second collection visit. APOE was a significant contributing factor; however, BDNF Val66Met was not. Using a similar logistic regression analysis, baseline proBDNF was not found to be associated with future cognition. DISCUSSION: This study further supports that mBDNF measured in the serum of older adults may reflect a protective role while proBDNF requires further investigation.

Bacopa monnieri supplementation has no effect on serum brain-derived neurotrophic factor levels but beneficially modulates nuclear factor kappa B and cyclic AMP response element-binding protein levels in healthy elderly subjects.

Background and Aim: Bacopa monnieri is an Ayurvedic herb that has been used for multiple conditions, most notably to augment cognition, particularly memory and attention. Multiple mechanisms, including raising brain-derived neurotrophic factor (BDNF), have been proposed and investigated in animal models that require translational studies in humans. Methods: Bacopa was administered in an open-labeled study to cognitively healthy controls over a 3-month period. Cognition and mood were assessed using the Montreal Cognitive Assessment (MoCA) and geriatric depression scale (GDS) at the baseline and 3-month visit. Laboratories were assessed for safety and serum levels of mature (mBDNF) and proBDNF were quantified. In a subset of subjects, intracellular signaling processes were assessed using western blot analysis. Results: Bacopa was provided to 35 subjects and was well-tolerated except for 4 (11%) subjects who early terminated due to known, reversible, and gastrointestinal side effects (i.e., nausea, diarrhea). Over the 3 months, the GDS and the total MoCA did not significantly change; however, the delayed-recall subscale significantly improved (baseline: 3.8 ± 1.2, 3-months: 4.3 ± 0.9; P = 0.032). Serum mBDNF and proBDNF levels did not significantly change. Cyclic AMP response element-binding protein (CREB) phosphorylation significantly increased (P = 0.028) and p65 nuclear factor kappa B (NF-κB) phosphorylation significantly decreased (P = 0.030). Conclusion: These results suggest that Bacopa may exert an anti-inflammatory effect through NF-κB and improve intracellular signaling processes associated with synaptogenesis (CREB). The future placebo-controlled studies are recommended. Relevance for Patients: B. monnieri will require larger, blinded trials to better understand potential mechanisms, interactions, and utilization.

Impact of gulf war toxic exposures after mild traumatic brain injury.

Chemical and pharmaceutical exposures have been associated with the development of Gulf War Illness (GWI), but how these factors interact with the pathophysiology of traumatic brain injury (TBI) remains an area of study that has received little attention thus far. We studied the effects of pyridostigmine bromide (an anti-nerve agent) and permethrin (a pesticide) exposure in a mouse model of repetitive mild TBI (r-mTBI), with 5 impacts over a 9-day period, followed by Gulf War (GW) toxicant exposure for 10 days beginning 30 days after the last head injury. We then assessed the chronic behavioral and pathological sequelae 5 months after GW agent exposure. We observed that r-mTBI and GWI cumulatively affect the spatial memory of mice in the Barnes maze and result in a shift of search strategies employed by r-mTBI/GW exposed mice. GW exposure also produced anxiety-like behavior in sham animals, but r-mTBI produced disinhibition in both the vehicle and GW treated mice. Pathologically, GW exposure worsened r-mTBI dependent axonal degeneration and neuroinflammation, increased oligodendrocyte cell counts, and increased r-mTBI dependent phosphorylated tau, which was found to colocalize with oligodendrocytes in the corpus callosum. These results suggest that GW exposures may worsen TBI-related deficits. Veterans with a history of both GW chemical exposures as well as TBI may be at higher risk for worse symptoms and outcomes. Subsequent exposure to various toxic substances can influence the chronic nature of mTBI and should be considered as an etiological factor influencing mTBI recovery.

Exogenous lipase administration alters gut microbiota composition and ameliorates Alzheimer's disease-like pathology in APP/PS1 mice.

Alzheimer's disease (AD) represents the most common form of dementia in the elderly with no available disease modifying treatments. Altered gut microbial composition has been widely acknowledged as a common feature of AD, which potentially contributes to progression or onset of AD. To assess the hypothesis that Candida rugosa lipase (CRL), which has been shown to enhance gut microbiome and metabolite composition, can rebalance the gut microbiome composition and reduce AD pathology, the treatment effects in APPswe/PS1de9 (APP/PS1) mice were investigated. The analysis revealed an increased abundance of Acetatifactor and Clostridiales vadin BB60 genera in the gut; increased lipid hydrolysis in the gut lumen, normalization of peripheral unsaturated fatty acids, and reduction of neuroinflammation and memory deficits post treatment. Finally, we demonstrated that the evoked benefits on memory could be transferred via fecal matter transplant (FMT) into antibiotic-induced microbiome-depleted (AIMD) wildtype mice, ameliorating their memory deficits. The findings herein contributed to improve our understanding of the role of the gut microbiome in AD's complex networks and suggested that targeted modification of the gut could contribute to amelioration of AD neuropathology.

Sex-Specific Regulation of ß-Secretase: A Novel Estrogen Response Element (ERE)-Dependent Mechanism in Alzheimer's Disease.

Women have a higher prevalence and incidence of Alzheimer's disease (AD) than age-matched men, and loss of estrogen might be partially responsible for the higher risk of AD in aged women. While ß-secretase (BACE1) plays an important role in AD pathogenesis, whether BACE1 involved the sex difference in AD pathology remains unclear. This study investigated the hypothesis that estrogen regulates BACE1 transcription via the estrogen response element (ERE) and designated pathways. Using estrogen receptor (ER) knock-out mice and mutagenesis of EREs in HEK293 cells, we demonstrated sex-specific inhibition of BACE1 transcription by estrogen via direct binding to ERE sites and ERα. We also used a repressor of estrogen receptor activity (REA) and showed that an REA-ERE complex downregulated BACE1. A chromatin immunoprecipitation assay analysis determined that all three EREs at the BACE1 promoter were required for estradiol-mediated downregulation of BACE1 transcription in mice. Last, we confirmed the impairment of the REA pathway in the cortex of female AD patients. Our study identified an estrogen-specific BACE1 transcriptional regulation pathway from cell and animal models to AD patients.SIGNIFICANCE STATEMENT With the increase in the aging population and Alzheimer's disease worldwide, an urgent need to find effective approaches to treat or prevent AD. Women have a higher prevalence and incidence of AD than men. Identification of the sex-specific risk for AD may be valuable for disease prevention. This study evaluated several estrogen response element (ERE) sites on the promoter of ß-secretase (BACE1), a key enzyme for AD pathology. We demonstrated that estrogen downregulated BACE1 transcription through direct binding and complex formation with ERE and cofactors. Our novel findings provide evidence that an estrogen supplement may decrease the risk of AD in menopausal and postmenopausal women. Furthermore, this study demonstrates the "sex-specific" mechanisms of BACE1 as a role in AD pathogenesis.

Adaptive Immune Responses Associated with the Central Nervous System Pathology of Gulf War Illness.

Gulf War Illness is a multisymptomatic condition which affects 30% of veterans from the 1991 Gulf War. While there is evidence for a role of peripheral cellular and humoral adaptive immune responses in Gulf War Illness, a potential role of the adaptive immune system in the central nervous system pathology of this condition remains unknown. Furthermore, many of the clinical features of Gulf War Illness resembles those of autoimmune diseases, but the biological processes are likely different as the etiology of Gulf War Illness is linked to hazardous chemical exposures specific to the Gulf War theatre. This review discusses Gulf War chemical-induced maladaptive immune responses and a potential role of cellular and humoral immune responses that may be relevant to the central nervous system symptoms and pathology of Gulf War Illness. The discussion may stimulate investigations into adaptive immunity for developing novel therapies for Gulf War Illness.

MMP9 modulation improves specific neurobehavioral deficits in a mouse model of Alzheimer's disease.

BACKGROUND: Matrix metallopeptidase 9 (MMP9) has been implicated in a variety of neurological disorders, including Alzheimer's disease (AD), where MMP9 levels are elevated in the brain and cerebrovasculature. Previously our group demonstrated apolipoprotein E4 (apoE4) was less efficient in regulating MMP9 activity in the brain than other apoE isoforms, and that MMP9 inhibition facilitated beta-amyloid (Aß) elimination across the blood-brain barrier (BBB) METHODS: In the current studies, we evaluated the impact of MMP9 modulation on Aß disposition and neurobehavior in AD using two approaches, (1) pharmacological inhibition of MMP9 with SB-3CT in apoE4 x AD (E4FAD) mice, and (2) gene deletion of MMP9 in AD mice (MMP9KO/5xFAD) RESULTS: Treatment with the MMP9 inhibitor SB-3CT in E4FAD mice led to reduced anxiety compared to placebo using the elevated plus maze. Deletion of the MMP9 gene in 5xFAD mice also reduced anxiety using the open field test, in addition to improving sociability and social recognition memory, particularly in male mice, as assessed through the three-chamber task, indicating certain behavioral alterations in AD may be mediated by MMP9. However, neither pharmacological inhibition of MMP9 or gene deletion of MMP9 affected spatial learning or memory in the AD animals, as determined through the radial arm water maze. Moreover, the effect of MMP9 modulation on AD neurobehavior was not due to changes in Aß disposition, as both brain and plasma Aß levels were unchanged in the SB-3CT-treated E4FAD animals and MMP9KO/AD mice compared to their respective controls. CONCLUSIONS: In total, while MMP9 inhibition did improve specific neurobehavioral deficits associated with AD, such as anxiety and social recognition memory, modulation of MMP9 did not alter spatial learning and memory or Aß tissue levels in AD animals. While targeting MMP9 may represent a therapeutic strategy to mitigate aspects of neurobehavioral decline in AD, further work is necessary to understand the nature of the relationship between MMP9 activity and neurological dysfunction.

Novel, natural allosteric inhibitors and enhancers of Candida rugosa lipase activity.

Candida rugosa lipase (CRL) is an enzyme commonly used in medicinal and biotechnological applications. Allosteric modulators of CRL could aid in modifying lipase-related diseases as well as improving biotechnological processes. Thus, a combinatorial approach of computational in-silico and high-throughput in-vitro screening was used to identify allosteric modulators of CRL. The screening of natural product libraries resulted in 132 compounds of which 53 were tested in-vitro. Subsequently, four inhibitors and three enhancers were identified of which rutin and cynaroside represented the strongest inhibitors of CRL activity (IC50: 227 ± 26 µM and 446 ± 15 µM, respectively) and NP-008496 the strongest enhancer (EC50: 425 ± 18 µM). All three compounds were predicted to bind the same allosteric site suggesting a common mechanism. Therefore, the present study demonstrated a reliable work-flow, identified an allosteric site of CRL and determined inhibitors and enhancers with numerous potential medical and biotechnological applications.

Candida rugosa lipase alters the gastrointestinal environment in wild-type mice.

Diet and commercially available supplements can significantly impact the gut microbial composition; however, the effects of supplements often lack scientific data demonstrating the effects on healthy and diseased individuals. Hence, it was investigated, whether a frequently used supplement in humans, Candida rugosa lipase (CRL), gets delivered active beyond the stomach in the intestinal tract of C57BL/6 J mice and its impact on the gut microbial community and environment. We showed for the first time the movement of CRL in an active state through the mouse digestive tract by determination of intestinal CRL activity and free fatty acids concentrations. The short- and long-term administration of CRL resulted in significant alterations of the gut microbiome, favoring the growth of, for instance, Verrucomicrobia but also other species associated with normal body mass index (BMI) or butyrate expression, both considered beneficial. In addition, we showed that these changes persisted after supplementation and that gut barrier integrity was unaffected by the treatment. In conclusion, CRL can be delivered in an active state beyond the stomach and supplementation altered the murine gut microbiome favoring beneficial bacterial species, which may be of relevance in humans in healthy but also potentially in disease states.

The Influence of Baseline Alzheimer's Disease Severity on Cognitive Decline and CSF Biomarkers in the NILVAD Trial.

We examined the effects of a dihydropyridine calcium channel blocker nilvadipine with anti-inflammatory properties on cognition and cerebrospinal fluid (CSF) biomarkers by baseline Alzheimer's disease (AD) severity. Exploratory analyses were performed on the dataset (n = 497) of a phase III randomized placebo-controlled trial to examine the response to nilvadipine in AD subjects stratified by baseline AD severity into very mild (MMSE ≥ 25), mild (MMSE 20-24) and moderate AD (MMSE < 20). The outcome measures included total and subscale scores of the Alzheimer's Disease Assessment Scale Cognitive 12 (ADAS-Cog 12), the Clinical Dementia Rating Scale sum of boxes (CDR-sb) and the AD composite score (ADCOMS). Cerebrospinal fluid biomarkers Aß38, Aß40, Aß42, neurofilament light chain (NFL), neurogranin, YKL-40, total tau and P181 tau (ptau) were measured in a subset of samples (n = 55). Regression analyses were adjusted for confounders to specifically examine the influence of nilvadipine and baseline AD severity on cognitive outcomes over 78-weeks. Compared to their respective placebo-controls, nilvadipine-treated, very mild AD subjects showed less decline, whereas moderate AD subjects showed a greater cognitive decline on the ADAS-Cog 12 test and the ADCOMS. A lower decline was observed after nilvadipine treatment for a composite memory trait in very mild AD subjects and a composite language trait in mild AD subjects. Cerebrospinal fluid Aß42/Aß40 ratios were increased in mild AD and decreased in moderate AD patients treated with nilvadipine, compared to their respective controls. Among moderate AD subjects, levels of ptau, total tau, neurogranin and YKL-40 increased in subjects treated with nilvadipine compared to placebo. These studies suggest that baseline AD severity influenced the treatment outcome in the NILVAD trial and that future clinical trials of nilvadipine should be restricted to mild and very mild AD patients. Trial Registration: NCT02017340 Registered 20 December 2013, https://clinicaltrials.gov/ct2/show/NCT02017340 EUDRACT Reference Number 2012-002764-27 Registered 04 February 2013, https://www.clinicaltrialsregister.eu/ctr-search/search?query=2012-002764-27.

Proteomic Identification of Pathways Responsible for the Estradiol Therapeutic Window in AD Animal Models.

Benefits and risks were reported for hormone therapy (HT) to prevent chronic disease, including Alzheimer's disease (AD). While the Women's Health Initiative (WHI) found no protective effect of HT on the cognitive function of women whose treatment was initiated far past the onset of menopause, other studies showed reduced risk of AD with midlife treatment, versus increased risk of AD with late treatment. These suggest a critical window during which estradiol must be administered to prevent cognitive decline and AD in women. Our published work supports this, by demonstrating that early and long-term estradiol treatment improves cognitive function and reduce Aß accumulation in AD mouse models with estradiol deficiency, while there is no effect of late and short-term estradiol treatment on AD neuropathogenesis. However, little is known about the molecular mechanisms underlying the critical window and whether different protein networks are responsible for the brain estradiol deficiency-associated risk of AD in females. In this study, we used proteomics to identify target protein pathways that are activated during the estradiol therapeutic window in AD mouse model. Our results showed that different signaling pathways were involved in the regulatory effects of estradiol on MAP1A and hemoglobin α. Estradiol treatment increased the level of MAP1A through the phosphorylation of ERK1/2 and increased the level of hemoglobin α through the phosphorylation of AKT. This study has provided molecular insights into the "critical window" theory and identifies specific target proteins of therapeutic responsiveness that may lead to improved treatment strategies and optimal estradiol therapy.

A fast, miniaturised in-vitro assay developed for quantification of lipase enzyme activity.

The discovery of allosteric modulators is a multi-disciplinary approach, which is time- and cost-intensive. High-throughput screening combined with novel computational tools can reduce these factors. Thus, we developed an enzyme activity assay, which can be included in the drug discovery work-flow subsequent to the in-silico library screening. While the in-silico screening yields in the identification of potential allosteric modulators, the developed in-vitro assay allows for the characterisation of them. Candida rugosa lipase (CRL), a glyceride hydrolysing enzyme, has been selected for the pilot development. The assay conditions were adjusted to CRL's properties including pH, temperature and substrate specificity for two different substrates. The optimised assay conditions were validated and were used to characterise Tropolone, which was identified as an allosteric modulator. In conclusion, the assay is a reliable, reproducible, and robust tool, which can be streamlined with in-silico screening and incorporated in an automated high-throughput screening workflow.

Lifelong behavioral and neuropathological consequences of repetitive mild traumatic brain injury.

Objective: Exposure to repetitive concussion, or mild traumatic brain injury (mTBI), has been linked with increased risk of long-term neurodegenerative changes, specifically chronic traumatic encephalopathy (CTE). To date, preclinical studies largely have focused on the immediate aftermath of mTBI, with no literature on the lifelong consequences of mTBI in these models. This study provides the first account of lifelong neurobehavioral and histological consequences of repetitive mTBI providing unique insight into the constellation of evolving and ongoing pathologies with late survival. Methods: Male C57BL/6J mice (aged 2-3 months) were exposed to either single or repetitive mild TBI or sham procedure. Thereafter, animals were monitored and assessed at 24 months post last injury for measures of motor coordination, learning deficits, cognitive function, and anxiety-like behavior prior to euthanasia and preparation of the brains for detailed neuropathological and protein biochemical studies. Results: At 24 months survival animals exposed to r-mTBI showed clear evidence of learning and working memory impairment with a lack of spatial memory and vestibule-motor vestibulomotor deficits compared to sham animals. Associated with these late behavioral deficits there was evidence of ongoing axonal degeneration and neuroinflammation in subcortical white matter tracts. Notably, these changes were also observed after a single mTBI, albeit to a lesser degree than repetitive mTBI. Interpretation: In this context, our current data demonstrate, for the first time, that rather than an acute, time limited event, mild TBI can precipitate a lifelong degenerative process. These data therefore suggest that successful treatment strategies should consider both the acute and chronic nature of mTBI.

Plasma cytokine IL-6 levels and subjective cognitive decline: preliminary findings.

OBJECTIVE: Detection of Alzheimer's disease (AD) prior to clinical inception will be paramount for introducing disease modifying treatments. We have begun collecting baseline characteristics of a community cohort for longitudinal assessment and testing of antecedent blood-based biomarkers. We describe the baseline visit from the first 131 subjects in relationship to a commonly described cytokine, interleukin 6 (IL-6). METHODS: Subjects from the community presented for a free memory screening with varying degrees of memory concern. We quantified the baseline plasma levels of the cytokine IL-6 and assessed cognition (Montreal Cognitive Assessment, MoCA) and mood (Geriatric Depression Scale, GDS) in relationship to their memory concern. RESULTS: Baseline MoCA scores were inversely related to age, and this association was influenced by an AD risk factor, Apolipoprotein E (APOE4) carrier status. The degree of subjective cognitive decline correlated with GDS and was inversely related to MoCA scores. Interleukin 6 levels were related to age, body mass index, and years of education. CONCLUSIONS: It will be important to assess how these baseline IL-6 levels and forthcoming novel biomarkers relate to future cognitive decline. Copyright © 2017 John Wiley & Sons, Ltd.

Alzheimer's disease pathological lesions activate the spleen tyrosine kinase.

The pathology of Alzheimer's disease (AD) is characterized by dystrophic neurites (DNs) surrounding extracellular Aß-plaques, microgliosis, astrogliosis, intraneuronal tau hyperphosphorylation and aggregation. We have previously shown that inhibition of the spleen tyrosine kinase (Syk) lowers Aß production and tau hyperphosphorylation in vitro and in vivo. Here, we demonstrate that Aß-overexpressing Tg PS1/APPsw, Tg APPsw mice, and tau overexpressing Tg Tau P301S mice exhibit a pathological activation of Syk compared to wild-type littermates. Syk activation is occurring in a subset of microglia and is age-dependently increased in Aß-plaque-associated dystrophic neurites of Tg PS1/APPsw and Tg APPsw mice. In Tg Tau P301S mice, a pure model of tauopathy, activated Syk occurs in neurons that show an accumulation of misfolded and hyperphosphorylated tau in the cortex and hippocampus. Interestingly, the tau pathology is exacerbated in neurons that display high levels of Syk activation supporting a role of Syk in the formation of tau pathological species in vivo. Importantly, human AD brain sections show both pathological Syk activation in DNs around Aß deposits and in neurons immunopositive for pathological tau species recapitulating the data obtained in transgenic mouse models of AD. Additionally, we show that Syk overexpression leads to increased tau accumulation and promotes tau hyperphosphorylation at multiple epitopes in human neuron-like SH-SY5Y cells, further supporting a role of Syk in the formation of tau pathogenic species. Collectively, our data show that Syk activation occurs following Aß deposition and the formation of tau pathological species. Given that we have previously shown that Syk activation also promotes Aß formation and tau hyperphosphorylation, our data suggest that AD pathological lesions may be self-propagating via a Syk dependent mechanism highlighting Syk as an attractive therapeutic target for the treatment of AD.

Phospholipid profiling of plasma from GW veterans and rodent models to identify potential biomarkers of Gulf War Illness.

Gulf War Illness (GWI), which affects at least one fourth of the 700,000 veterans deployed to the Gulf War (GW), is characterized by persistent and heterogeneous symptoms, including pain, fatigue and cognitive problems. As a consequence, this illness remains difficult to diagnose. Rodent models have been shown to exhibit different symptomatic features of GWI following exposure to particular GW agents (e.g. pyridostigmine bromide, permethrin and DEET) and/or stress. Preclinical analyses have shown the activation of microglia and astroglia as a pathological hallmark in these mouse and rat models. Although much has been learned in recent years from these different rodent models and independent clinical studies, characterization studies to identify overlapping features of GWI in animals and humans have been missing. Thus, we aimed to identify biomarkers that co-occur in the plasma of rodent models of GWI and human GWI patients. We observed increases of multiple phospholipid (PL) species across all studied cohorts. Furthermore, these data suggested dysfunction within ether and docosahexaenoic acid and arachidonic acid containing PL species in relation to GWI. As these PL species play a role in inflammatory processes, these findings suggest a possible role for inflammatory imbalance in GWI. Overall, we show that the peripheral lipid disturbances are present both in human GWI patients and in the preclinical rodent models of GWI, highlighting the importance of lipidomics as a potential platform for further biomarker discovery and supporting the value of GW agent exposed models of GWI.

Complementary proteomic approaches reveal mitochondrial dysfunction, immune and inflammatory dysregulation in a mouse model of Gulf War Illness.

PURPOSE: Long-term consequences of combined pyridostigmine bromide (PB) and permethrin (PER) exposure in C57BL6/J mice using a well-characterized mouse model of exposure to these Gulf War (GW) agents were explored at the protein level. EXPERIMENTAL DESIGN: We used orthogonal proteomic approaches to identify pathways that are chronically impacted in the mouse CNS due to semiacute GW agent exposure early in life. These analyses were performed on soluble and membrane-bound protein fractions from brain samples using two orthogonal isotopic labeling LC-MS/MS proteomic approaches-stable isotope dimethyl labeling and iTRAQ. RESULTS: The use of these approaches allowed for greater coverage of proteins than was possible by either one alone and revealed both distinct and overlapping datasets. This combined analysis identified changes in several mitochondrial, as well as immune and inflammatory pathways after GW agent exposure. CONCLUSIONS AND CLINICAL RELEVANCE: The work discussed here provides insight into GW agent exposure dependent mechanisms that adversely affect mitochondrial function and immune and inflammatory regulation. Collectively, our work identified key pathways which were chronically impacted in the mouse CNS following acute GW agent exposure, this may lead to the identification of potential targets for therapeutic intervention in the future. Long-term consequences of combined PB and PER exposure in C57BL6/J mice using a well-characterized mouse model of exposure to these GW agents were explored at the protein level. Expanding on earlier work, we used orthogonal proteomic approaches to identify pathways that are chronically impacted in the mouse CNS due to semiacute GW agent exposure early in life. These analyses were performed on soluble and membrane-bound protein fractions from brain samples using two orthogonal isotopic labeling LC-MS/MS proteomic approaches-stable isotope dimethyl labeling and iTRAQ. The use of these approaches allowed for greater coverage of proteins than was possible by either one alone and revealed both distinct and overlapping datasets. This combined analysis identified changes in several mitochondrial, as well as immune and inflammatory pathways after GW agent exposure. The work discussed here provides insight into GW agent exposure dependent mechanisms that adversely affect mitochondrial function and immune and inflammatory regulation at 5 months postexposure to PB + PER.

Genetics and Other Risk Factors for Past Concussions in Active-Duty Soldiers.

Risk factors for concussion in active-duty military service members are poorly understood. The present study examined the association between self-reported concussion history and genetics (apolipoprotein E [APOE], brain-derived neurotrophic factor [BDNF], and D2 dopamine receptor genes [DRD2]), trait personality measures (impulsive-sensation seeking and trait aggression-hostility), and current alcohol use. The sample included 458 soldiers who were preparing to deploy for Operation Iraqi Freedom/Operation Enduring Freedom. For those with the BDNF Met/Met genotype, 57.9% (11/19) had a history of one or more prior concussions, compared with 35.6% (154/432) of those with other BDNF genotypes (p = 0.049, odds ratio [OR] = 2.48). APOE and DRD2 genotypes were not associated with risk for past concussions. Those with the BDNF Met/Met genotype also reported greater aggression and hostility personality characteristics. When combined in a predictive model, prior military deployments, being male, and having the BDNF Met/Met genotype were independently associated with increased lifetime history of concussions in active-duty soldiers. Replication in larger independent samples is necessary to have more confidence in both the positive and negative genetic associations reported in this study.

Translational potential of long-term decreases in mitochondrial lipids in a mouse model of Gulf War Illness.

Gulf War Illness (GWI) affects 25% of veterans from the 1990-1991 Gulf War (GW) and is accompanied by damage to the brain regions involved in memory processing. After twenty-five years, the chronic pathobiology of GWI is still unexplained. To address this problem, we examined the long-term consequences of GW exposures in an established GWI mouse model to identify biological processes that are relevant to the chronic symptoms of GWI. Three-month old male C57BL6 mice were exposed for 10days to GW agents (pyridostigmine bromide and permethrin). Barnes Maze testing conducted at 15- and 16-months post-exposure revealed learning and memory impairment. Immunohistochemical analyses showed astroglia and microglia activation in the hippocampi of exposed mice. Proteomic studies identified perturbation of mitochondria function and metabolomics data showed decreases in the Krebs cycle compounds, lactate, ß-hydroxybutyrate and glycerol-3 phosphate in the brains of exposed mice. Lipidomics data showed decreases in fatty acids, acylcarnitines and phospholipids, including cardiolipins in the brains of exposed mice. Pilot biomarker studies showed that plasma from exposed mice and veterans with GWI had increases in odd-chain, and decreases in long-chain, acylcarnitines compared to their respective controls. Very long-chain acylcarnitines were decreased in veterans with GWI compared to controls. These studies suggest that mitochondrial lipid disturbances might be associated with GWI and that further investigation is required to determine its role in the pathophysiology of this illness. Targeting mitochondrial function may provide effective therapies for GWI, and that lipid abnormalities could serve as biomarkers of GWI.

Identification of Telomerase-activating Blends From Naturally Occurring Compounds.

Context • Telomeres are repeated deoxyribonucleic acid (DNA) sequences (TTAGGG) that are located on the 5' ends of chromosomes, and they control the life span of eukaryotic cells. Compelling evidence has shown that the length of a person's life is dictated by the limited number of times that a human cell can divide. The enzyme telomerase has been shown to bind to and extend the length of telomeres. Thus, strategies for activating telomerase may help maintain telomere length and, thus, may lead to improved health during aging. Objective • The current study intended to investigate the effects of several natural compounds on telomerase activity in an established cell model of telomere shortening (ie, IMR90 cells). Design • The research team designed an in vitro study. Setting • The study was conducted at Roskamp Institute in Sarasota, FL, USA. Intervention • The tested single compounds were (1) α-lipoic acid, (1) green tea extract, (2) dimethylaminoethanol L-bitartrate (DMAE L-bitartrate), (3) N-acetyl-L-cysteine hydrochloride (HCL), (4) chlorella powder, (5) L-carnosine, (6) vitamin D3, (7) rhodiola PE 3%/1%, (8) glycine, (9) French red wine extract, (10) chia seed extract, (11) broccoli seed extract, and (12) Astragalus (TA-65). The compounds were tested singly and as blends. Outcome Measures • Telomerase activity for single compounds and blends of compounds was measured by the TeloTAGGG telomerase polymerase chain reaction (PCR) enzyme-linked immunosorbent assay (ELISA). The 4 most potent blends were investigated for their effects on cancer-cell proliferation and for their potential effects on the cytotoxicity and antiproliferative activity of a chemotherapeutic agent, the topoisomerase I inhibitor topotecan. The benefits of 6 population doublings (PDs) were measured for the single compounds, and the 4 blends were compared to 3 concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Results • Certain of the compounds increased telomerase activity, and combinations of the top-ranking compounds were able to increase telomerase activity significantly, from 51% to 290%, relative to controls. Conclusions • The results have confirmed that many naturally occurring compounds hold the potential to activate telomerase and that certain of those compounds have demonstrated synergistic effects to produce more potent blends. Given the relationship between telomere shortening, aging, and the decline of tissue function, it is reasonable to hypothesize that such telomerase-activating blends may have health-promoting benefits, particularly in relation to aging-associated conditions. Further investigation of such blends in human studies that are designed to evaluate safety and the effects on telomere length are thus warranted.