Apathy in patients with Alzheimer's disease is a cost-driving factor.

BACKGROUND: Apathy is the most frequent neuropsychiatric symptom in patients with dementia of the Alzheimer's type (DAT). We analyzed the influence of apathy on the resource use of DAT patients and their caregivers. METHODS: Included were baseline data of 107 DAT patients from a randomized clinical trial on apathy treatment. The Resource Utilization in Dementia (RUD) instrument assessed costs over a 1-month period prior to baseline. Cost predictors were determined via a least absolute shrinkage and selection operator (LASSO). RESULTS: On average, total monthly costs were €3070, of which €2711 accounted for caregivers' and €359 for patients' costs. An increase of one point in the Apathy Evaluation Scale resulted in a 4.1% increase in total costs. DISCUSSION: Apathy is a significant cost driving factor for total costs in mild to moderate DAT. Effective treatment of apathy might be associated with reduced overall costs in DAT.

Point-of-Care Ultrasound to Detect Acute Large Vessel Occlusions in Stroke Patients: A Proof-of-Concept Study.

BACKGROUND AND PURPOSE: A primary admission of patients with suspected acute ischemic stroke and large vessel occlusion (LVO) to centers capable of providing endovascular stroke therapy (EVT) may induce shorter time to treatment and better functional outcomes. One of the limitations in this strategy is the need for accurately identifying LVO patients in the prehospital setting. We aimed to study the feasibility and diagnostic performance of point-of-care ultrasound (POCUS) for the detection of LVO in patients with acute stroke. METHODS: We conducted a proof-of-concept study and selected 15 acute ischemic stroke patients with angiographically confirmed LVO and 15 patients without LVO. Duplex ultrasonography (DUS) of the common carotid arteries was performed, and flow profiles compatible with LVO were scored independently by one experienced and one junior neurologist. RESULTS: Among the 15 patients with LVO, 6 patients presented with an occlusion of the carotid-T and 9 patients presented with an M1 occlusion. Interobserver agreement between the junior and the experienced neurologist was excellent (kappa = 0.813, p < 0.001). Flow profiles of the CAA allowed the detection of LVO with a sensitivity of 73%, a positive predictive value of 92 and 100%, and a c-statistics of 0.83 (95%CI = 0.65-0.94) and 0.87 (95%CI = 0.69-0.94) (experienced neurologist and junior neurologist, respectively). In comparison with clinical stroke scales, DUS was associated with better trade-off between sensitivity and specificity. CONCLUSION: POCUS in acute stroke setting is feasible, it may serve as a complementary tool for the detection of LVO and is potentially applicable in the prehospital phase.

Alpha-Synuclein-Specific Naturally Occurring Antibodies Inhibit Aggregation In Vitro and In Vivo.

Parkinson's disease (PD) is associated with motor and non-motor symptoms and characterized by aggregates of alpha-synuclein (αSyn). Naturally occurring antibodies (nAbs) are part of the innate immune system, produced without prior contact to their specific antigen, and polyreactive. The abundance of nAbs against αSyn is altered in patients with PD. In this work, we biophysically characterized nAbs against αSyn (nAbs-αSyn) and determined their biological effects. nAbs-αSyn were isolated from commercial intravenous immunoglobulins using column affinity purification. Biophysical properties were characterized using a battery of established in vitro assays. Biological effects were characterized in HEK293T cells transiently transfected with fluorescently tagged αSyn. Specific binding of nAbs-αSyn to monomeric αSyn was demonstrated by Dot blot, ELISA, and Surface Plasmon Resonance. nAbs-αSyn did not affect viability of HEK293T cells as reported by Cell Titer Blue and LDH Assays. nAbs-αSyn inhibited fibrillation of αSyn reported by the Thioflavin T aggregation assay. Altered fibril formation was confirmed with atomic force microscopy. In cells transfected with EGFP-tagged αSyn we observed reduced formation of aggresomes, perinuclear accumulations of αSyn aggregates. The results demonstrate that serum of healthy individuals contains nAbs that specifically bind αSyn and inhibit aggregation of αSyn in vitro. The addition of nAbs-αSyn to cultured cells affects intracellular αSyn aggregates. These findings help understanding the role of the innate immune systems for the pathogenesis of PD and suggest that systemic αSyn binding agents could potentially affect neuronal αSyn pathology.

Bupropion for the Treatment of Apathy in Alzheimer Disease: A Randomized Clinical Trial.

Importance: Apathy is a frequent neuropsychiatric symptom in dementia of Alzheimer type and negatively affects the disease course and patients' and caregivers' quality of life. Effective treatment options are needed. Objective: To examine the efficacy and safety of the dopamine and noradrenaline reuptake inhibitor bupropion in the treatment of apathy in patients with dementia of Alzheimer type. Design, Setting, and Participants: This 12-week, multicenter, double-blind, placebo-controlled, randomized clinical trial was conducted in a psychiatric and neurological outpatient setting between July 2010 and July 2014 in Germany. Patients with mild-to-moderate dementia of Alzheimer type and clinically relevant apathy were included. Patients with additional clinically relevant depressed mood were excluded. Data analyses were performed between August 2018 and August 2019. Interventions: Patients received either bupropion or placebo (150 mg for 4 weeks plus 300 mg for 8 weeks). In case of intolerability of 300 mg, patients continued to receive 150 mg throughout the study. Main Outcomes and Measures: Change on the Apathy Evaluation Scale-Clinician Version (AES-C) (score range, 18-72 points) between baseline and week 12 was the primary outcome parameter. Secondary outcome parameters included measures of neuropsychiatric symptoms, cognition, activities of daily living, and quality of life. Outcome measures were assessed at baseline and at 4, 8, and 12 weeks. Results: A total of 108 patients (mean [SD] age, 74.8 [5.9] years; 67 men [62%]) were included in the intention-to-treat analysis, with 54 randomized to receive bupropion and 54 randomized to receive placebo. The baseline AES-C score was comparable between the bupropion group and the placebo group (mean [SD], 52.2 [8.7] vs 50.4 [8.2]). After controlling for the baseline AES-C score, site, and comedication with donepezil or galantamine, the mean change in the AES-C score between the bupropion and placebo groups was not statistically significant (mean change, 2.22; 95% CI, -0.47 to 4.91; P = .11). Results on secondary outcomes showed statistically significant differences between bupropion and placebo in terms of total neuropsychiatric symptoms (mean change, 5.52; 95% CI, 2.00 to 9.04; P = .003) and health-related quality of life (uncorrected for multiple comparisons; mean change, -1.66; 95% CI, -3.01 to -0.31; P = .02) with greater improvement in the placebo group. No statistically significant changes between groups were found for activities of daily living (mean change, -2.92; 95% CI, -5.89 to 0.06; P = .05) and cognition (mean change, -0.27; 95% CI, -3.26 to 2.73; P = .86). The numbers of adverse events (bupropion group, 39 patients [72.2%]; placebo group, 33 patients [61.1%]) and serious adverse events (bupropion group, 5 patients [9.3%]; placebo group, 2 patients [3.7%]) were comparable between groups. Conclusions and Relevance: Although it is safe, bupropion was not superior to placebo for the treatment of apathy in patients with dementia of Alzheimer type in the absence of clinically relevant depressed mood. Trial Registration: EU Clinical Trials Register Identifier: 2007-005352-17.

α1-antitrypsin mitigates NLRP3-inflammasome activation in amyloid ß1-42-stimulated murine astrocytes.

BACKGROUND: Neuroinflammation has an essential impact on the pathogenesis and progression of Alzheimer's disease (AD). Mostly mediated by microglia and astrocytes, inflammatory processes lead to degeneration of neuronal cells. The NLRP3-inflammasome (NOD-like receptor family, pyrin domain containing 3) is a key component of the innate immune system and its activation results in secretion of the proinflammatory effectors interleukin-1ß (IL-1ß) and interleukin-18 (IL-18). Under physiological conditions, cytosolic NLRP3-inflammsome is maintained in an inactive form, not able to oligomerize. Amyloid ß1-42 (Aß1-42) triggers activation of NLRP3-inflammasome in microglia and astrocytes, inducing oligomerization and thus recruitment of proinflammatory proteases. NLRP3-inflammasome was found highly expressed in human brains diagnosed with AD. Moreover, NLRP3-deficient mice carrying mutations associated with familial AD were partially protected from deficits associated with AD. The endogenous protease inhibitor α1-antitrypsin (A1AT) is known for its anti-inflammatory and anti-apoptotic properties and thus could serve as therapeutic agent for NLRP3-inhibition. A1AT protects neurons from glutamate-induced toxicity and reduces Aß1-42-induced inflammation in microglial cells. In this study, we investigated the effect of Aß1-42-induced NLRP3-inflammasome upregulation in primary murine astrocytes and its regulation by A1AT. METHODS: Primary cortical astrocytes from BALB/c mice were stimulated with Aß1-42 and treated with A1AT. Regulation of NLRP3-inflammasome was examined by immunocytochemistry, PCR, western blot and ELISA. Our studies included an inhibitor of NLRP3 to elucidate direct interactions between A1AT and NLRP3-inflammasome components. RESULTS: Our study revealed that A1AT reduces Aß1-42-dependent upregulation of NLRP3 at the mRNA and protein levels. Furthermore, A1AT time-dependently mitigated the expression of caspase 1 and its cleavage product IL-1ß in Aß1-42-stimulated astrocytes. CONCLUSION: We conclude that Aß1-42-stimulation results in an upregulation of NLRP3, caspase 1, and its cleavage products in astrocytes. A1AT time-dependently hampers neuroinflammation by downregulation of Aß1-42-mediated NLRP3-inflammasome expression and thus may serve as a pharmaceutical opportunity for the treatment of Alzheimer's disease.

Extending the functional characteristics of naturally occurring autoantibodies against ß-Amyloid, Prion Protein and α-Synuclein.

BACKGROUND: Abnormal aggregation of proteins induces neuronal cell loss in neurodegenerative disorders such as Alzheimer's Disease, Creutzfeldt-Jakob Disease and Parkinson's Disease. Specific stimuli initialize conformational changes in physiological proteins, causing intra- or extracellular protein aggregation. We and other groups have identified naturally occurring autoantibodies (nAbs) as part of the human antibody pool that are able to prevent peptide fibrillation. These nAbs show a rescue effect following exposure of toxic aggregates on neurons, and they support microglial uptake of aggregated peptides. OBJECTIVE: Identification of a putative common epitope among the relevant proteins ß-Amyloid, α-Synuclein and Prion Protein for the respective nAbs. MATERIAL AND METHODS: Binding affinity between the aforementioned proteins and nAbs was tested by Dot Blot, ELISA and SPR-technology. Furthermore, the functionality of the protein-nAbs-complexes was studied in Thioflavin-T assays and microglial uptake experiments to study dependent inhibition of protein aggregation and enhancement of Fcγ mediated uptake by microglial cells. RESULTS: ß-Amyloid and Prion Protein fragment showed considerable binding affinity and functional efficacy for all applied nAbs. Thereby, no significant difference within the different nAbs was detected. In contrast, α-Synuclein was bound exclusively by nAbs-α-Synuclein, which was reproduced in all binding studies. Surprisingly, functional assays with α-Synuclein revealed no significant effect of nAbs in comparison to IVIg treatment. However, all applied nAbs as well as IVIg show a minimal functionality on the microglial uptake of α-Synuclein. CONCLUSION: nAbs-Aß, nAbs-PrP possibly display comparable affinity to the same structural epitope within Aß and PrP106-126 A117V whereas the epitope recognized by nAbs-α-Syn is only present in α-Syn. The structural similarity of Aß and PrP fragment promotes the outline for an efficient antibody for the treatment of several neurodegenerative disorders and extend the functional characteristics of the investigated nAbs.

Modern Interdisciplinary and Interhospital Acute Stroke Therapy-What Patients Think About It and What They Really Understand.

BACKGROUND: Access to reperfusion therapies in patients with large vessel occluding acute ischemic stroke demands process reorganization and optimization. Neurovascular networks are being built up to provide 24/7 endovascular stroke therapy service. In times of an increasingly complex stroke rescue chain little is known about patients' and their relatives' treatment awareness. METHODS: All patients, who received any kind of acute reperfusion treatment between January and August 2017 in the university hospital Aachen, and their proxies, were included in the survey. Patients were either primarily or secondarily transferred. RESULTS: For all questions regarding stroke treatment patients and their caregivers provided concurring answers. 40% of both patients and caregivers did not understand the treatment that was performed. Finally, patients who perceived on their own that stroke detection was delayed had significantly longer onset to door times than patients who did not have this impression. CONCLUSIONS: This study showed that patients' and proxies' answers correlated significantly. In case of patients' unavailability extrapolation of treatment satisfaction from answers by proxies might be permitted. High percentages of patients and caregivers do not understand relevant information, possibly due to limits of communication in an emergency setting or deficits in communication during the hospital stay. More emphasis should be laid on providing further information during the hospital stay.

Improvement of Endovascular Stroke Treatment: A 24-Hour Neuroradiological On-Site Service Is Not Enough.

BACKGROUND AND PURPOSE: With the advent of endovascular stroke treatment (EST) with mechanical thrombectomy, stroke treatment has also become more challenging. Purpose of this study was to investigate whether a fulltime neuroradiological on-site service and workflow optimization with a structured documentation of the interdisciplinary stroke workflow resulted in improved procedural times. MATERIAL AND METHODS: Procedural times of 322 consecutive patients, who received EST (1) before (n = 96) and (2) after (n = 126) establishing a 24-hour neuroradiological on-site service as well as (3) after implementation of a structured interdisciplinary workflow documentation ("Stroke Check") (n = 100), were analysed. RESULTS: A fulltime neuroradiological on-site service resulted in a nonsignificant improvement of procedural times during out-of-hours admissions (p ≥ 0.204). Working hours and out-of-hours procedural times improved significantly, if additional workflow optimization was realized (p ≤ 0.026). CONCLUSIONS: A 24-hour interventional on-site service is a major prerequisite to adequately provide modern reperfusion therapies in patients with acute ischemic stroke. However, simple measures like standardized and focused documentation that affect the entire interdisciplinary pre- and intrahospital stroke rescue chain seem to be important.

Transfer of stroke patients impairs eligibility for endovascular stroke treatment.

BACKGROUND: Many patients who are potentially eligible for endovascular stroke treatment (EST) receive intravenous rtPA in the closest stroke unit before being transferred to tertiary centres for EST. It has been shown that clinical outcome of transferred and EST-treated patients is comparable to that of patients with direct access to EST. We analysed clinical outcome of patients, who were transferred and eventually not treated due to clinical and/or radiological deterioration. METHODS: We retrospectively analysed our prospectively maintained stroke registry for patients who were transferred for stroke therapy. RESULTS: Four hundred twenty-two of 1208 patients (35.1%), who were admitted for acute reperfusion stroke therapy between 03/10 and 01/15 were eligible for EST. Ninety-one (7.5%) of these patients were admitted specifically for EST from remote hospitals. Favorable clinical outcome rates after 90 days (mRS≤2) were comparable between 63 transferred and 295 directly-admitted patients, who received EST (P=0.699). However, transferred patients, who were eligible for EST on initial admission, were less likely to receive EST after transfer (P<0.001): twenty-two of 91 patients (24.2%), who were transferred for EST, became ineligible during transfer due to infarct demarcation. Procedural times of treated and untreated transferred patients were comparable (P≥0.508). There was a trend towards worse clinical outcome in untreated patients, without reaching statistical significance (OR, 0.269; 95% CI, 0.55-1.324; P=0.119). CONCLUSIONS: EST should be provided directly whenever possible as one in four transferred stroke patients becomes ineligible for EST during transfer. If direct transfer is not possible, indication for EST should be re-assessed after transfer.

Anterior sacral meningocele infected with Fusobacterium in a patient with recently diagnosed colorectal carcinoma - a case report.

BACKGROUND: Anterior sacral meningoceles are rare, and usually occur with other malformations of the posterior lower spine. While these are more frequently reported in pediatric cohorts, we report a case in an elderly woman. CASE PRESENTATION: We report on a 71 year-old woman with a recently diagnosed colorectal adenocarcinoma who presented with a severe bacterial meningitis. The cerebrospinal fluid cell count revealed a pleocytosis of 80,000 cells/µl and a severe disturbance of the blood-brain-barrier. Fusobacterium nucleatum was cultured as the causing pathogen. A lumbar MRI showed, in addition to contrast-enhancing meninges as sign of inflammation, a presacral mass. In the next step, the mass was diagnosed as an anterior sacral meningocele connected to the gut. An adequate antibiotic was used to treat the leptomeningitis. The connection between gut and meningocele was closed surgically and the patient recovered well and underwent further treatment of her colorectal adenocarcinoma. CONCLUSION: We report on a case of meningitis with an anterior sacral meningocele that was connected to the gut in a patient with a infiltrative colorectal adenocarcinoma. Anatomic variants have to be considered as rare causes of meningitis with typical intestinal germs.

Vaccination strategies in tauopathies and synucleinopathies.

Vaccination therapies constitute potential treatment options in neurodegenerative disorders such as Alzheimer disease or Parkinson disease. While a lot of research has been performed on vaccination against extracellular amyloid ß, the focus recently shifted toward vaccination against the intracellular proteins tau and α-synuclein, with promising results in terms of protein accumulation reduction. In this review, we briefly summarize lessons to be learned from clinical vaccination trials in Alzheimer disease that target amyloid ß. We then focus on tau and α-synuclein. For both proteins, we provide important data on protein immunogenicity, and put them into context with data available from both animals and human vaccination trials targeted at tau and α-synuclein. Together, we give a comprehensive overview about current clinical data, and discuss associated problems.

Mortality and cardiorespiratory complications in trochanteric femoral fractures: a ten year retrospective analysis.

PURPOSE: Despite intense research and innovations in peri-operative management, a high mortality rate and frequent systemic complications in trochanteric femoral fractures persist. The aim of the present study was to identify predictive factors for mortality and cardio-respiratory complications after different treatment methods in a ten year period at a level I trauma centre. METHODS: Retrospectively, all patients above 60 years of age with trochanteric femoral fracture between January 2000 and May 2011 were analyzed at a level I trauma centre. Demographic variables, comorbidities, and data regarding the surgical procedures, including required transfusions and post-operative complications, were evaluated, and the in-hospital mortality was recorded. The grade of osteoporosis was classified radiographically using the Singh index. RESULTS: The in-hospital mortality rate was 8.2% among 437 patients (male/female ratio = 110/327, mean age = 81 years) with extramedullary open (n = 144), intramedullary (n = 166), and extramedullary minimally invasive (n = 125) procedures. Significant influential factors on in-hospital mortality were identified with binary logistic regression analysis: an age of ≥90 years (P = 0.011), male sex (P = 0.003), a high American Society of Anesthesiologists (ASA) grade (3-5, P = 0.042), and a high osteoporosis grade (Singh index 3-1, P = 0.011). A total of 21.5% of the study population suffered cardio-respiratory complications post-operatively. The specific mortality was 28.7% (P < 0.001), which was influenced by a high ASA grade (3-5, P = 0.002) and a high transfusion rate (P = 0.004). Minimally invasive locked plating was associated with increased cardio-respiratory complications (P = 0.031). CONCLUSIONS: This study identified high patient age, distinctive comorbidities, male sex, and high osteoporosis grade as significant risk factors for increased in-hospital mortality in the treatment of trochanteric femoral fractures. Furthermore, high ASA grade and a liberal transfusion regime led to an increased incidence of cardio-respiratory complications. Patient-specific characteristics, especially osteoporosis grade and pre-existing medical conditions, may assist in the identification of high-risk patients and allow a patient-specific geriatric co-management plan.

TREM2 rare variant p.R47H is not associated with Parkinson's disease.

Variant p.R47H of triggering receptor expressed on myeloid cells 2 (TREM2) has been associated with Parkinson's disease (PD). We screened this TREM2-variant in 821 PD patients including 261 demented PD patients (PDD) and in healthy controls (n = 919). Neither the entire PD nor the small PDD sample was associated with p.R47H.

Reduction of glutamate-induced excitotoxicity in murine primary neurons involving calpain inhibition.

Excessive glutamate secretion leads to excitotoxicity, which has been shown to underlie neurodegenerative disorders. Excitotoxicity is in part exerted by overactivation of calpains, which promote neuronal cell death via induction of limited proteolysis of the cellular proteins p35, regulatory subunit of cyclin-dependent kinase 5, and αII-spectrin. We used primary murine neuronal cells in a model of glutamate toxicity. The protease inhibitor α1-antitrypsin was able to prevent glutamate toxicity as determined by MTT assay and immunofluorescence. Calpain and caspase 3 activity were reduced following α1-antitrypsin treatment, as assessed by calpain and caspase 3 activity assays. In addition we could observe a modulation of cleavage of the calpain/caspase substrates αII-spectrin and p35 in Western blots. In summary, α1-antitrypsin shows inhibitory effects on excitotoxicity of primary neurons involving the inhibition of calpain activity. The advantage of using α1-antitrypsin is that the substance is already in clinical use for the treatment of patients with hereditary α1-antitrypsin deficiency. Further experiments are required in animal models of neurodegenerative disorders to assess the suitability of this substance in patients suffering from Alzheimer's disease or Parkinson's disease.

Measuring Compounds in Exhaled Air to Detect Alzheimer's Disease and Parkinson's Disease.

BACKGROUND: Alzheimer's disease (AD) is diagnosed based upon medical history, neuropsychiatric examination, cerebrospinal fluid analysis, extensive laboratory analyses and cerebral imaging. Diagnosis is time consuming and labour intensive. Parkinson's disease (PD) is mainly diagnosed on clinical grounds. OBJECTIVE: The primary aim of this study was to differentiate patients suffering from AD, PD and healthy controls by investigating exhaled air with the electronic nose technique. After demonstrating a difference between the three groups the secondary aim was the identification of specific substances responsible for the difference(s) using ion mobility spectroscopy. Thirdly we analysed whether amyloid beta (Aß) in exhaled breath was causative for the observed differences between patients suffering from AD and healthy controls. METHODS: We employed novel pulmonary diagnostic tools (electronic nose device/ion-mobility spectrometry) for the identification of patients with neurodegenerative diseases. Specifically, we analysed breath pattern differences in exhaled air of patients with AD, those with PD and healthy controls using the electronic nose device (eNose). Using ion mobility spectrometry (IMS), we identified the compounds responsible for the observed differences in breath patterns. We applied ELISA technique to measure Aß in exhaled breath condensates. RESULTS: The eNose was able to differentiate between AD, PD and HC correctly. Using IMS, we identified markers that could be used to differentiate healthy controls from patients with AD and PD with an accuracy of 94%. In addition, patients suffering from PD were identified with sensitivity and specificity of 100%. Altogether, 3 AD patients out of 53 participants were misclassified. Although we found Aß in exhaled breath condensate from both AD and healthy controls, no significant differences between groups were detected. CONCLUSION: These data may open a new field in the diagnosis of neurodegenerative disease such as Alzheimer's disease and Parkinson's disease. Further research is required to evaluate the significance of these pulmonary findings with respect to the pathophysiology of neurodegenerative disorders.

α1-antitrypsin modulates microglial-mediated neuroinflammation and protects microglial cells from amyloid-ß-induced toxicity.

BACKGROUND: One hallmark of Alzheimer disease is microglial activation. Therapeutic approaches for this neurodegenerative disease include the modulation of microglial cells. α1-antitrypsin (A1AT) has been shown to exert anti-inflammatory effects on macrophages and lung epithelial cells and an inhibition of calpain activity in neutrophil granulocytes. Nothing is known about the effect of A1AT on microglial-mediated neuroinflammation. Our aim was to investigate the effect of A1AT on amyloid-ß (Aß)- and LPS-treated microglial cells in vitro with respect to cytokine production, stress pathways, cell viability, phagocytotic abilities and the underlying mechanisms. METHODS: Primary microglial cells were isolated from Swiss Webster mouse embryos on embryonic day 13.5. Cytokines in the supernatants of treated primary microglial cells were analyzed with ELISAs, and accumulated nitrite was detected with Griess reagents. Intracellular stress pathways were investigated in cell lysates using western blotting. Intracellular calcium levels were detected in BV-2 microglial cells loaded with the Ca2+-sensitive (fluorescent) dye Fluo-4. Calpain activity in primary microglial cells was assessed by using a calpain activity assay. Cell viability of Aß-treated microglial cells was analyzed using MTT assay. Phagocytosis of Aß was evaluated with western blot analysis. RESULTS: Upon co-administration, A1AT reduced pro-inflammatory mediators induced by LPS or Aß. Interestingly, we detected a reduction in calpain activity and in the concentration of intracellular calcium that might mediate the anti-inflammatory effects of A1AT. Inhibition of the classic activation pathways, such as phosphorylation of mitogen-activated protein kinases or activation of protein kinase A were excluded as a mechanism of A1AT-mediated effects. In addition, A1AT increased the viability of Aß-treated microglial cells and reduced Aß phagocytosis. CONCLUSIONS: We provide evidence on the mechanism of action of A1AT on microglial-mediated neuroinflammation in vitro. Our in vitro data indicate that A1AT treatment modulates microglial cells in inflammatory conditions and that this modulation is due to an inhibition of calpain activity and intracellular calcium levels. The underlying mechanisms of the effects observed here are promising for future therapeutic strategies and should thus be further pursued in transgenic mouse models of Alzheimer disease.

The endogenous α7 nicotinic acetylcholine receptor antagonist kynurenic acid modulates amyloid-ß-induced inflammation in BV-2 microglial cells.

Amyloid-ß has been shown to interact with the α7 nicotinic acetylcholine receptor on neuronal cells. Not much is known on the effect on microglial cells and whether this effect can be modulated by the endogenous α7 nicotinic acetylcholine receptor antagonist kynurenic acid. Our aim was to investigate the effect of kynurenic acid on amyloid-ß-treated BV-2 microglial cells with respect to α7 nicotinic acetylcholine receptor expression, cell viability, cytokine production and phagocytotic abilities. Therefore BV-2 cells were treated with oligomeric or fibrillar forms of amyloid-ß(1-40) and co-treated with kynurenic acid. α7 nicotinic acetylcholine receptor quantity was investigated using Western blotting. Cell viability was assessed by staining cells with fluorescein diacetate and propidium iodide. Pro-inflammatory cytokines were measured in cell culture supernatants of treated cells with ELISAs; NO with Griess reagents and amyloid-ß uptake were investigated with fluorescence-activated cell sorting and verified by Western blotting. Amyloid-ß nor kynurenic acid did have an effect on the protein level of the α7 nicotinic acetylcholine receptor. Amyloid-Beta induced cell mortality was unchanged after addition of kynurenic acid. However, kynurenic acid co-treatment reduced the pro-inflammatory cytokines tumour necrosis factor-α and IL-6 and amyloid-ß phagocytosis. We provide evidence for an immunomodulating effect of the endogenous α7 nicotinic acetylcholine receptor antagonist kynurenic acid. Our findings indicate a role for kynurenic acid in amyloid-ß associated neuroinflammation in Alzheimer disease.

Prion peptide uptake in microglial cells--the effect of naturally occurring autoantibodies against prion protein.

In prion disease, a profound microglial activation that precedes neurodegeneration has been observed in the CNS. It is still not fully elucidated whether microglial activation has beneficial effects in terms of prion clearance or whether microglial cells have a mainly detrimental function through the release of pro-inflammatory cytokines. To date, no disease-modifying therapy exists. Several immunization attempts have been performed as one therapeutic approach. Recently, naturally occurring autoantibodies against the prion protein (nAbs-PrP) have been detected. These autoantibodies are able to break down fibrils of the most commonly used mutant prion variant PrP106-126 A117V and prevent PrP106-126 A117V-induced toxicity in primary neurons. In this study, we examined the phagocytosis of the prion peptide PrP106-126 A117V by primary microglial cells and the effect of nAbs-PrP on microglia. nAbs-PrP considerably enhanced the uptake of PrP106-126 A117V without inducing an inflammatory response in microglial cells. PrP106-126 A117V uptake was at least partially mediated through scavenger receptors. Phagocytosis of PrP106-126 A117V with nAbs-PrP was inhibited by wortmannin, a potent phosphatidylinositol 3-kinase inhibitor, indicating a separate uptake mechanism for nAbs-PrP mediated phagocytosis. These data suggest the possible mechanisms of action of nAbs-PrP in prion disease.