VEGF-C prophylaxis favors lymphatic drainage and modulates neuroinflammation in a stroke model.

Meningeal lymphatic vessels (MLVs) promote tissue clearance and immune surveillance in the central nervous system (CNS). Vascular endothelial growth factor-C (VEGF-C) regulates MLV development and maintenance and has therapeutic potential for treating neurological disorders. Herein, we investigated the effects of VEGF-C overexpression on brain fluid drainage and ischemic stroke outcomes in mice. Intracerebrospinal administration of an adeno-associated virus expressing mouse full-length VEGF-C (AAV-mVEGF-C) increased CSF drainage to the deep cervical lymph nodes (dCLNs) by enhancing lymphatic growth and upregulated neuroprotective signaling pathways identified by single nuclei RNA sequencing of brain cells. In a mouse model of ischemic stroke, AAV-mVEGF-C pretreatment reduced stroke injury and ameliorated motor performances in the subacute stage, associated with mitigated microglia-mediated inflammation and increased BDNF signaling in brain cells. Neuroprotective effects of VEGF-C were lost upon cauterization of the dCLN afferent lymphatics and not mimicked by acute post-stroke VEGF-C injection. We conclude that VEGF-C prophylaxis promotes multiple vascular, immune, and neural responses that culminate in a protection against neurological damage in acute ischemic stroke.

VEGF-C promotes brain-derived fluid drainage, confers neuroprotection, and improves stroke outcomes.

Meningeal lymphatic vessels promote tissue clearance and immune surveillance in the central nervous system (CNS). Vascular endothelium growth factor-C (VEGF-C) is essential for meningeal lymphatic development and maintenance and has therapeutic potential for treating neurological disorders, including ischemic stroke. We have investigated the effects of VEGF-C overexpression on brain fluid drainage, single cell transcriptome in the brain, and stroke outcomes in adult mice. Intra-cerebrospinal fluid administration of an adeno-associated virus expressing VEGF-C (AAV-VEGF-C) increases the CNS lymphatic network. Post-contrast T1 mapping of the head and neck showed that deep cervical lymph node size and drainage of CNS-derived fluids were increased. Single nuclei RNA sequencing revealed a neuro-supportive role of VEGF-C via upregulation of calcium and brain-derived neurotrophic factor (BDNF) signaling pathways in brain cells. In a mouse model of ischemic stroke, AAV-VEGF-C pretreatment reduced stroke injury and ameliorated motor performances in the subacute stage. AAV-VEGF-C thus promotes CNS-derived fluid and solute drainage, confers neuroprotection, and reduces ischemic stroke damage. Short abstract: Intrathecal delivery of VEGF-C increases the lymphatic drainage of brain-derived fluids confers neuroprotection, and improves neurological outcomes after ischemic stroke.

CSF-to-dura gateways.

Postmortem microstructural studies together with in vivo magnetic resonance imaging show that human arachnoid granulations are porous channels that serve as transient filtration conduits for cerebrospinal fluid to flow directly into dural interstitial tissue, but not into venous sinuses (Shah et al. 2022. J. Exp. Med.https://doi.org/10.1084/jem.20220618).

Exenatide once weekly for alcohol use disorder investigated in a randomized, placebo-controlled clinical trial.

BackgroundAlcohol use disorder (AUD) is a chronic, relapsing brain disorder that accounts for 5% of deaths annually, and there is an urgent need to develop new targets for therapeutic intervention. The glucagon-like peptide-1 (GLP-1) receptor agonist exenatide reduces alcohol consumption in rodents and nonhuman primates, but its efficacy in patients with AUD is unknown.MethodsIn a randomized, double-blinded, placebo-controlled clinical trial, treatment-seeking AUD patients were assigned to receive exenatide (2 mg subcutaneously) or placebo once weekly for 26 weeks, in addition to standard cognitive-behavioral therapy. The primary outcome was reduction in number of heavy drinking days. A subgroup also completed functional MRI (fMRI) and single-photon emission CT (SPECT) brain scans.ResultsA total of 127 patients were enrolled. Our data revealed that although exenatide did not significantly reduce the number of heavy drinking days compared with placebo, it significantly attenuated fMRI alcohol cue reactivity in the ventral striatum and septal area, which are crucial brain areas for drug reward and addiction. In addition, dopamine transporter availability was lower in the exenatide group compared with the placebo group. Exploratory analyses revealed that exenatide significantly reduced heavy drinking days and total alcohol intake in a subgroup of obese patients (BMI > 30 kg/m2). Adverse events were mainly gastrointestinal.ConclusionThis randomized controlled trial on the effects of a GLP-1 receptor agonist in AUD patients provides new important knowledge on the effects of GLP-1 receptor agonists as a novel treatment target in addiction.Trial registrationEudraCT: 2016-003343-11. ClinicalTrials.gov (NCT03232112).FundingNovavi Foundation; Research Foundation, Mental Health Services, Capital Region of Denmark; Research Foundation, Capital Region of Denmark; Ivan Nielsen Foundation; A.P. Moeller Foundation; Augustinus Foundation; Woerzner Foundation; Grosserer L.F. Foghts Foundation; Hartmann Foundation; Aase and Ejnar Danielsen Foundation; P.A. Messerschmidt and Wife Foundation; and Lundbeck Foundation.

Emergent White Matter Degeneration in the rTg-DI Rat Model of Cerebral Amyloid Angiopathy Exhibits Unique Proteomic Changes.

Cerebral amyloid angiopathy (CAA), characterized by cerebral vascular amyloid accumulation, neuroinflammation, microbleeds, and white matter (WM) degeneration, is a common comorbidity in Alzheimer disease and a prominent contributor to vascular cognitive impairment and dementia. WM loss was recently reported in the corpus callosum (CC) in the rTg-DI rat model of CAA. The current study shows that the CC exhibits a much lower CAA burden compared with the adjacent cortex. Sequential Window Acquisition of All Theoretical Mass Spectra tandem mass spectrometry was used to show specific proteomic changes in the CC with emerging WM loss and compare them with the proteome of adjacent cortical tissue in rTg-DI rats. In the CC, annexin A3, heat shock protein ß1, and cystatin C were elevated at 4 months (M) before WM loss and at 12M with evident WM loss. Although annexin A3 and cystatin C were also enhanced in the cortex at 12M, annexin A5 and the leukodystrophy-associated astrocyte proteins megalencephalic leukoencephalopathy with subcortical cysts 1 and GlialCAM were distinctly elevated in the CC. Pathway analysis indicated neurodegeneration of axons, reflected by reduced expression of myelin and neurofilament proteins, was common to the CC and cortex; activation of Tgf-ß1 and F2/thrombin was restricted to the CC. This study provides new insights into the proteomic changes that accompany WM loss in the CC of rTg-DI rats.

Development of an MRI-Compatible Nasal Drug Delivery Method for Probing Nicotine Addiction Dynamics.

Substance abuse is a fundamentally dynamic disease, characterized by repeated oscillation between craving, drug self-administration, reward, and satiety. To model nicotine addiction as a control system, a magnetic resonance imaging (MRI)-compatible nicotine delivery system is needed to elicit cyclical cravings. Using a concentric nebulizer, inserted into one nostril, we delivered each dose equivalent to a single cigarette puff by a syringe pump. A control mechanism permits dual modes: one delivers puffs on a fixed interval programmed by researchers; with the other, subjects press a button to self-administer each nicotine dose. We tested the viability of this delivery method for studying the brain's response to nicotine addiction in three steps. First, we established the pharmacokinetics of nicotine delivery, using a dosing scheme designed to gradually achieve saturation. Second, we lengthened the time between microdoses to elicit craving cycles, using both fixed-interval and subject-driven behavior. Finally, we demonstrate a potential application of our device by showing that a fixed-interval protocol can reliably identify neuromodulatory targets for pharmacotherapy or brain stimulation. Our MRI-compatible nasal delivery method enables the measurement of neural circuit responses to drug doses on a single-subject level, allowing the development of data-driven predictive models to quantify individual dysregulations of the reward control circuit causing addiction.

Diffuse white matter loss in a transgenic rat model of cerebral amyloid angiopathy.

Diffuse white matter (WM) disease is highly prevalent in elderly with cerebral small vessel disease (cSVD). In humans, cSVD such as cerebral amyloid angiopathy (CAA) often coexists with Alzheimer's disease imposing a significant impediment for characterizing their distinct effects on WM. Here we studied the burden of age-related CAA pathology on WM disease in a novel transgenic rat model of CAA type 1 (rTg-DI). A cohort of rTg-DI and wild-type rats was scanned longitudinally using MRI for characterization of morphometry, cerebral microbleeds (CMB) and WM integrity. In rTg-DI rats, a distinct pattern of WM loss was observed at 9 M and 11 M. MRI also revealed manifestation of small CMB in thalamus at 6 M, which preceded WM loss and progressively enlarged until the moribund disease stage. Histology revealed myelin loss in the corpus callosum and thalamic CMB in all rTg-DI rats, the latter of which manifested in close proximity to occluded and calcified microvessels. The quantitation of CAA load in rTg-DI rats revealed that the most extensive microvascular Aß deposition occurred in the thalamus. For the first time using in vivo MRI, we show that CAA type 1 pathology alone is associated with a distinct pattern of WM loss.

MIF inhibition enhances pulmonary angiogenesis and lung development in congenital diaphragmatic hernia.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a complex birth anomaly with significant mortality and morbidity. Lung hypoplasia and persistent pulmonary hypertension (PPHN) limit survival in CDH. Macrophage migration inhibitory factor (MIF), a key regulator of innate immunity, is involved in hypoxia-induced vascular remodeling and PPHN. We hypothesized that antenatal inhibition of MIF in CDH fetuses, would reduce vascular remodeling, and improve angiogenesis and lung development. METHODS: Pregnant rats were randomized into three groups: Control, nitrofen, and nitrofen + ISO-92. Lung volumes of pups were measured by CT scanning. Right ventricular systolic pressure (RVSP) and vascular wall thickness (VWT) were measured together with MIF concentration, angiogenesis markers, lung morphometry, and histology. RESULTS: Prenatal treatment with ISO-92, an MIF inhibitor, improved normalization of static lung volume, lung volume-to-body weight ratio, decreased alveolar septal thickness, RVSP and VWT and improved radial alveolar count as compared to the non-treated group. Expression of MIF was unaffected by ISO-92; however, ISO-92 increased p-eNOS and VEGF activities and reduced arginase 1, 2 and Sflt-1. CONCLUSION: Prenatal inhibition of MIF activity in CDH rat model improves angiogenesis and lung development. This selective intervention may be a future therapeutic strategy to reduce the morbidity and mortality of this devastating condition.

Simultaneous Preclinical Positron Emission Tomography-Magnetic Resonance Imaging Study of Lymphatic Drainage of Chelator-Free 64Cu-Labeled Nanoparticles.

BACKGROUND: Hybrid positron emission tomography (PET)-magnetic resonance imaging (MRI) systems have been taken in use as new clinical diagnostic tools including detection and therapy planning of cancer. To reduce the amount of contrast agents injected in patients while fully benefitting both modalities, dual-modality probes are required. MATERIAL AND METHODS: This study was first aimed at developing a hybrid PET-MRI probe by labeling superparamagnetic iron oxide nanoparticles (SPIONs) with 64Cu using a fast and chelator-free conjugation method, and second, to demonstrate the ability of the agent to target sentinel lymph nodes (SLNs) in vivo using simultaneous PET-MRI imaging. RESULTS: High labeling efficiency of 97% produced within 10-15 min was demonstrated at room temperature. 64Cu-SPIONs were chemically stable in mouse serum for 24 h and after intradermal injection in the hind paw of C57BL/6J mice, demonstrated specific accumulation in the SLN. Simultaneous PET-MRI clearly demonstrated visualization of 64Cu-SPIONs, in dynamic and static imaging sequences up to 24 h after administration. CONCLUSION: The use of a single hybrid probe and simultaneous hybrid imaging provides an efficient, complementary integration of quantitation and is expected to improve preoperative planning and intraoperative guidance of cancer treatments.

Does glucagon-like peptide-1 (GLP-1) receptor agonist stimulation reduce alcohol intake in patients with alcohol dependence: study protocol of a randomised, double-blinded, placebo-controlled clinical trial.

INTRODUCTION: Alcohol dependence is a major public health problem. It is underdiagnosed and undertreated. Even when treated, more than 2/3 of patients in abstinence-oriented treatment will relapse within the first year. Thus, there is an urgent need for efficacious medical treatment of alcohol dependence. Glucagon-like peptide-1 (GLP-1) receptor stimulation has proven to reduce alcohol consumption in preclinical experiments. However, the effect of GLP-1 receptor agonists in humans has to our knowledge, not yet been investigated. METHODS AND ANALYSIS: Design, participants and intervention: The effect of the once-weekly GLP-1-receptor-agonist exenatide will be investigated in a double-blinded, placebo-controlled, randomised clinical trial. 114 outpatients will be recruited and randomised to treatment with either placebo or exenatide once weekly for 26 weeks as a supplement to cognitive-behavioural therapy. The primary endpoint is reduction in number of 'heavy drinking days'. The secondary endpoints include changes in total alcohol consumption, days without consumption, changes in brain activity and function, smoking status, cognition, measures of quality of life and changes in phosphatidylethanol as a biomarker of alcohol consumption from baseline to follow-up at week 26. Status: Currently recruiting patients. ETHICS AND DISSEMINATION: Ethical approval has been obtained. Before screening, all patients will be provided oral and written information about the trial. The study results will be disseminated by peer-review publications and conference presentations and has the potential to reveal a completely new medical treatment of alcohol dependence.

Intrathecal morphine administration reduces postoperative pain and peripheral endocannabinoid levels in total knee arthroplasty patients: a randomized clinical trial.

BACKGROUND: The primary goal of this study was to determine whether administration of intrathecal morphine reduces postoperative pain. The secondary goal was to determine the effect of intrathecal morphine upon circulating levels of the weakly analgesic endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and the related lipids palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). METHODS: Forty two total knee arthroplasty (TKA) patients were enrolled in a prospective, double-blinded, randomized study. The intervention consisted of intrathecal morphine (200 µg) or placebo administered at the time of the spinal anesthesia. Postoperative pain was measured during the first 4 h after surgery while serum levels of AEA, 2-AG, PEA, OEA, and cortisol were measured at baseline and 4 h after surgery. RESULTS: Administration of intrathecal morphine reduced postoperative pain 4 h after TKA surgery compared to placebo (p = 0.005) and reduced postoperative systemic opioid consumption (p = 0.001). At baseline, intrathecal morphine led to a significant reduction in AEA, 2-AG, and OEA levels but did not affect PEA or cortisol levels. In patients administered intrathecal placebo, 2-AG levels were elevated 4 h after surgery; whereas patients receiving intrathecal morphine showed reductions in AEA, PEA, and OEA when compared to placebo. At 4 h after TKA surgery cortisol levels were significantly elevated in the placebo group and reduced in those receiving morphine. CONCLUSIONS: These results indicate that intrathecal morphine reduces postoperative pain in TKA patients. Furthermore, activation of central opioid receptors negatively modulates the endocannabinoid tone, suggesting that potent analgesics may reduce the stimulus for production of peripheral endocannabinoids. This study is the first to document the existence of rapid communication between the central opioid and peripheral endocannabinoid systems in humans. TRIAL REGISTRATION: This trial was registered retrospectively. TRIAL REGISTRY: NCT02620631 . Study to Examine Pain Relief With Supplemental Intrathecal Morphine in TKA Patients, NCT02620631 , 12/03/2015.

Interleukin-6 and leptin levels are associated with preoperative pain severity in patients with osteoarthritis but not with acute pain after total knee arthroplasty.

BACKGROUND: Identifying drivers of pain that can serve as novel drug targets is important for improving perioperative analgesia. Total knee arthroplasty (TKA) is associated with significant postoperative pain. Cytokines contribute to the pathophysiology of osteoarthritis (OA) and associated pain. However, the influence of perioperative cytokine levels after TKA surgery upon postoperative pain remains unexplored. METHODS: We designed a prospective observational study to profile three proinflammatory cytokines, interleukin-6 (IL-6), tumor necrosis factor α (TNFα), and leptin in serum, synovial, and cerebrospinal fluid of TKA patients perioperatively to determine associations between cytokine levels and pain. We characterized time-trajectories in cytokines pre- and post-surgery and explored their relationships to pain across gender. RESULTS: Preoperative pain, measured by functional pain disability scores (PDQ), was predictive of postoperative pain. There were no gender differences in severity of preoperative pain or acute postoperative pain. Serum IL-6, serum leptin, and synovial fluid leptin were positively correlated with body mass index and preoperative pain severity. Stratification of patients by gender revealed strong correlations between serum IL-6, leptin, and PDQ only in females, suggesting that females may be more sensitive to the nociceptive actions of these cytokines. Although serum IL-6 increased dramatically (and TNFα increased modestly) four hours after surgery and remained elevated at 72h; they were not associated with the severity of acute postoperative pain. CONCLUSIONS: Our data suggest that while preoperative chronic pain is predictive of the severity of acute postoperative pain in TKA patients, the pre- and post-operative inflammatory status does not predict postoperative pain.

Metabolic profiling of dividing cells in live rodent brain by proton magnetic resonance spectroscopy (1HMRS) and LCModel analysis.

RATIONALE: Dividing cells can be detected in the live brain by positron emission tomography or optical imaging. Here we apply proton magnetic resonance spectroscopy (1HMRS) and a widely used spectral fitting algorithm to characterize the effect of increased neurogenesis after electroconvulsive shock in the live rodent brain via spectral signatures representing mobile lipids resonating at ∼1.30 ppm. In addition, we also apply the same 1HMRS methodology to metabolically profile glioblastomas with actively dividing cells growing in RCAS-PDGF mice. METHODS: 1HMRS metabolic profiles were acquired on a 9.4T MRI instrument in combination with LCModel spectral analysis of: 1) rat brains before and after ECS or sham treatments and 2) RCAS-PDGF mice with glioblastomas and wild-type controls. Quantified 1HMRS data were compared to post-mortem histology. RESULTS: Dividing cells in the rat hippocampus increased ∼3-fold after ECS compared to sham treatment. Quantification of hippocampal metabolites revealed significant decreases in N-acetyl-aspartate but no evidence of an elevated signal at ∼1.3 ppm (Lip13a+Lip13b) in the ECS compared to the sham group. In RCAS-PDGF mice a high density (22%) of dividing cells characterized glioblastomas. Nile Red staining revealed a small fraction (3%) of dying cells with intracellular lipid droplets in the tumors of RCAS-PDGF mice. Concentrations of NAA were lower, whereas lactate and Lip13a+Lip13b were found to be significantly higher in glioblastomas of RCAS-PDGF mice, when compared to normal brain tissue in the control mice. CONCLUSIONS: Metabolic profiling using 1HMRS in combination with LCModel analysis did not reveal correlation between Lip13a+Lip13b spectral signatures and an increase in neurogenesis in adult rat hippocampus after ECS. However, increases in Lip13a+Lip13b were evident in glioblastomas suggesting that a higher density of actively dividing cells and/or the presence of lipid droplets is necessary for LCModel to reveal mobile lipids.

PTEN action in leukaemia dictated by the tissue microenvironment.

PTEN encodes a lipid phosphatase that is underexpressed in many cancers owing to deletions, mutations or gene silencing. PTEN dephosphorylates phosphatidylinositol (3,4,5)-triphosphate, thereby opposing the activity of class I phosphatidylinositol 3-kinases that mediate growth- and survival-factor signalling through phosphatidylinositol 3-kinase effectors such as AKT and mTOR. To determine whether continued PTEN inactivation is required to maintain malignancy, here we generate an RNA interference-based transgenic mouse model that allows tetracycline-dependent regulation of PTEN in a time- and tissue-specific manner. Postnatal Pten knockdown in the haematopoietic compartment produced highly disseminated T-cell acute lymphoblastic leukaemia. Notably, reactivation of PTEN mainly reduced T-cell leukaemia dissemination but had little effect on tumour load in haematopoietic organs. Leukaemia infiltration into the intestine was dependent on CCR9 G-protein-coupled receptor signalling, which was amplified by PTEN loss. Our results suggest that in the absence of PTEN, G-protein-coupled receptors may have an unanticipated role in driving tumour growth and invasion in an unsupportive environment. They further reveal that the role of PTEN loss in tumour maintenance is not invariant and can be influenced by the tissue microenvironment, thereby producing a form of intratumoral heterogeneity that is independent of cancer genotype.

VIP gene deletion in mice causes cardiomyopathy associated with upregulation of heart failure genes.

RATIONALE: Vasoactive Intestinal Peptide (VIP), a pulmonary vasodilator and inhibitor of vascular smooth muscle proliferation, is absent in pulmonary arteries of patients with idiopathic pulmonary arterial hypertension (PAH). We previously determined that targeted deletion of the VIP gene in mice leads to PAH with pulmonary vascular remodeling and right ventricular (RV) dilatation. Whether the left ventricle is also affected by VIP gene deletion is unknown. In the current study, we examined if VIP knockout mice (VIP(-/-)) develop both right (RV) and left ventricular (LV) cardiomyopathy, manifested by LV dilatation and systolic dysfunction, as well as overexpression of genes conducive to heart failure. METHODS: We examined VIP(-/-)and wild type (WT) mice using Magnetic Resonance Imaging (MRI) for evidence of cardiomyopathy associated with biventricular dilation and wall thickness changes. Lung tissue from VIP(-/-) and WT mice was subjected to whole-genome gene microarray analysis. RESULTS: Lungs from VIP(-/-) mice showed overexpression of cardiomyopathy genes: Myh1 was upregulated 224 times over WT, and Mylpf was increased 72 fold. Tnnt3 was increased 105 times and tnnc2 181 fold. Hearts were dilated in VIP(-/-) mice, with thinning of LV wall and increase in RV and LV chamber size, though RV enlargement varied. Weights of VIP(-/-) mice were consistently lower. CONCLUSIONS: Critically-important heart failure-related genes are upregulated in VIP(-/-) mice associated with the spontaneous cardiomyopathy phenotype, involving both left and right ventricles, suggesting that loss of the VIP gene orchestrates a panoply of pathogenic genes which are detrimental to both left and right cardiac homeostasis.

Report from a quality assurance program on patients undergoing the MILD procedure.

OBJECTIVES: To characterize trends in pain and functional outcomes and identify risk factors in patients with lumbar spinal stenosis (LSS) and neurogenic claudication undergoing the "Minimally Invasive Lumbar Decompression" (MILD) procedure. DESIGN: Retrospective observational cohort study. SETTING: Academic multidisciplinary pain center at Stony Brook Medicine. SUBJECTS: Patients undergoing the MILD procedure from October 2010 to November 2012. METHODS: De-identified perioperative, pain and function related data for 50 patients undergoing MILD were extracted from the Center for Pain Management's quality assessment database. Data included numerical rating scale (NRS), symptom severity and physical function (Zurich Claudication Questionnaire), functional status (Oswestry Disability Index [ODI]), pain interference scores (National Institutes of Health Patient-Reported Outcomes Measurement Information System [PROMIS]), and patients' self-reported low back and lower extremity pain distribution. RESULTS: No MILD patient incurred procedure-related complications. Average NRS scores decreased postoperatively and 64.3% of patients reported less pain at 3 months. Clinically meaningful functional ODI improvements of at least 20% from baseline were present in 25% of the patients at 6 months. Preliminary analysis of changes in PROMIS scores at 3 months revealed that pre-MILD "severe" lumbar canal stenosis may be associated with high risk of "no improvement." No such impact was observed for NRS or ODI outcomes. CONCLUSION: Overall, pain is reduced and functional status improved in LSS patients following the MILD procedure at 3 and 6 months. Given the small sample size, it is not yet possible to identify patient subgroups at risk for "no improvement." Continued follow-up of longer-term outcomes appears warranted to develop evidence-based patient selection criteria.

Brain metabolomic profiles of lung cancer patients prior to treatment characterized by proton magnetic resonance spectroscopy.

Cancer patients without evidence of brain metastases often exhibit constitutional symptoms, cognitive dysfunction and mood changes at the time of clinical diagnosis, i.e. prior to surgical and/or chemotherapy treatment. At present however, there is limited information on brain metabolic and functional status in patients with systemic cancers such as lung cancer prior to initiation of treatment. Therefore, a prospective, observational study was conducted on patients with a clinical diagnosis of lung cancer to assess the cerebral metabolic status before treatment using proton magnetic resonance spectroscopy ((1)HMRS). Together with neurocognitive testing, (1)HMRS was performed in the parietal and occipital cortices of patients diagnosed with a lung mass (N=17) and an age-matched control group (N=15). Glutamate concentrations in the occipital cortex were found to be lower in the patients compared to controls and the concentrations of creatine and phosphocreatine were significantly lower in the parietal cortex of the patients. The lung cancer patients were also characterized by greater fatigue scores (but not depression) prior to treatment when compared to controls. In addition, the serum concentration of interleukin-6 (proinflammatory cytokine) was higher in patients compared to controls; and the concentration of tumor-necrosis factor alpha ([TNF-α]) was positively correlated to the metabolic activity of the lung tumor as defined by the 2-deoxy-2-((18)F)fluoro-D-glucose ((18)FDG) positron emission tomography (PET) derived maximal standardized uptake values (SUV(max)). Finally, multivariate statistical modeling revealed that the concentration of N-acetyl-aspartate [NAA] in the occipital cortex was negatively associated with [TNF-α]. In conclusion, our data demonstrate that the cerebral metabolic status of patients with lung cancer is changed even prior to treatment. In addition, the association between inflammatory cytokines, SUV(max) and [NAA] points towards interactions between the cancer's inherent metabolic activity, systemic subclinical inflammation and brain function.

Is fetal brain monoamine oxidase inhibition the missing link between maternal smoking and conduct disorders?

Smoking is the leading cause of preventable illness in the world today. Prenatal cigarette smoke exposure (PCSE) is a particularly insidious form because so many of its associated health effects befall the unborn child and produce behavioural outcomes that manifest themselves only years later. Among these are the associations between PCSE and conduct disorders, which have been mostly ascribed to the deleterious effects of nicotine on the fetal brain. Here we hypothesize that inhibition of brain monoamine oxidase (MAO) during fetal brain development, secondary to maternal cigarette smoking and in addition to nicotine, is a likely contributor to this association. MAOs play a central role in monoaminergic balance in the brain, and their inhibition during fetal development - but not during adult life - is known to result in an aggressive phenotype in laboratory animals. This paper provides theoretical and experimental support for the notion that cigarette smoke-induced inhibition of MAO in the fetal brain, particularly when it occurs in combination with polymorphisms in the MAOA gene that lead to lower enzyme concentration in the brain, may result in brain morphologic and functional changes that enhance the risk of irritability, poor self-control and aggression in the offspring. It also encourages research to evaluate whether the interaction of smoking exposure during fetal development and MAOA genotype increases the risk for conduct disorder over that incurred by mere fetal exposure to tobacco smoke.

Interlaced x-ray microplanar beams: a radiosurgery approach with clinical potential.

Studies have shown that x-rays delivered as arrays of parallel microplanar beams (microbeams), 25- to 90-microm thick and spaced 100-300 microm on-center, respectively, spare normal tissues including the central nervous system (CNS) and preferentially damage tumors. However, such thin microbeams can only be produced by synchrotron sources and have other practical limitations to clinical implementation. To approach this problem, we first studied CNS tolerance to much thicker beams. Three of four rats whose spinal cords were exposed transaxially to four 400-Gy, 0.68-mm microbeams, spaced 4 mm, and all four rats irradiated to their brains with large, 170-Gy arrays of such beams spaced 1.36 mm, all observed for 7 months, showed no paralysis or behavioral changes. We then used an interlacing geometry in which two such arrays at a 90-degree angle produced the equivalent of a contiguous beam in the target volume only. By using this approach, we produced 90-, 120-, and 150-Gy 3.4 x 3.4 x 3.4 mm(3) exposures in the rat brain. MRIs performed 6 months later revealed focal damage within the target volume at the 120- and 150-Gy doses but no apparent damage elsewhere at 120 Gy. Monte Carlo calculations indicated a 30-microm dose falloff (80-20%) at the edge of the target, which is much less than the 2- to 5-mm value for conventional radiotherapy and radiosurgery. These findings strongly suggest potential application of interlaced microbeams to treat tumors or to ablate nontumorous abnormalities with minimal damage to surrounding normal tissue.