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1.
Prev Med Rep ; 35: 102268, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37342201

ABSTRACT

Infants born to mothers with type 2 diabetes (T2D) and gestational diabetes (GDM) are at an increased risk of being overweight/obese. Modifiable lifestyle factors play a role in prevention of overweight and obesity. In 2017, the Canadian 24 h Movement Guidelines for the Early Years (CMG) were released. Alongside physical activity recommendations, sweetened beverage consumption (SBC) recommendations were also released by the American Academy of Pediatrics in 2017. The objective of this study was to determine the knowledge pregnant women with T2D and GDM have on the CMG and SBC recommendations, and to determine what factors affect this. A survey with questions regarding demographics, socioeconomic variables and the CMG and SBC recommendations was administered to pregnant women at Diabetes in Pregnancy clinics in Calgary, Alberta from July 2019 to January 2020. Surveys were analyzed utilizing the non-parametric Kruskall-Wallis Rank-Sum test, chi-square test and linear regression. A total of 79 respondents with T2D and GDM were collected. Respondents had the highest knowledge of SBC recommendations and the lowest knowledge of CMG recommendations. A bachelor's or higher degree was associated with significantly higher knowledge scores than a high-school education or less. In conclusion, pregnant women with T2D and GDM in this study had overall poor knowledge of the CMG and SBC recommendations, with less knowledge regarding the CMG. Level of education was found to be associated with knowledge regarding these recommendations. Future programs to improve education around infant and toddler physical activity and SBC recommendations may be beneficial for this patient population.

2.
BMJ ; 380: e072003, 2023 03 29.
Article in English | MEDLINE | ID: mdl-36990505

ABSTRACT

OBJECTIVE: To determine the relative efficacy of structured named diet and health behaviour programmes (dietary programmes) for prevention of mortality and major cardiovascular events in patients at increased risk of cardiovascular disease. DESIGN: Systematic review and network meta-analysis of randomised controlled trials. DATA SOURCES: AMED (Allied and Complementary Medicine Database), CENTRAL (Cochrane Central Register of Controlled Trials), Embase, Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and ClinicalTrials.gov were searched up to September 2021. STUDY SELECTION: Randomised trials of patients at increased risk of cardiovascular disease that compared dietary programmes with minimal intervention (eg, healthy diet brochure) or alternative programmes with at least nine months of follow-up and reporting on mortality or major cardiovascular events (such as stroke or non-fatal myocardial infarction). In addition to dietary intervention, dietary programmes could also include exercise, behavioural support, and other secondary interventions such as drug treatment. OUTCOMES AND MEASURES: All cause mortality, cardiovascular mortality, and individual cardiovascular events (stroke, non-fatal myocardial infarction, and unplanned cardiovascular interventions). REVIEW METHODS: Pairs of reviewers independently extracted data and assessed risk of bias. A random effects network meta-analysis was performed using a frequentist approach and grading of recommendations assessment, development and evaluation (GRADE) methods to determine the certainty of evidence for each outcome. RESULTS: 40 eligible trials were identified with 35 548 participants across seven named dietary programmes (low fat, 18 studies; Mediterranean, 12; very low fat, 6; modified fat, 4; combined low fat and low sodium, 3; Ornish, 3; Pritikin, 1). At last reported follow-up, based on moderate certainty evidence, Mediterranean dietary programmes proved superior to minimal intervention for the prevention of all cause mortality (odds ratio 0.72, 95% confidence interval 0.56 to 0.92; patients at intermediate risk: risk difference 17 fewer per 1000 followed over five years), cardiovascular mortality (0.55, 0.39 to 0.78; 13 fewer per 1000), stroke (0.65, 0.46 to 0.93; 7 fewer per 1000), and non-fatal myocardial infarction (0.48, 0.36 to 0.65; 17 fewer per 1000). Based on moderate certainty evidence, low fat programmes proved superior to minimal intervention for prevention of all cause mortality (0.84, 0.74 to 0.95; 9 fewer per 1000) and non-fatal myocardial infarction (0.77, 0.61 to 0.96; 7 fewer per 1000). The absolute effects for both dietary programmes were more pronounced for patients at high risk. There were no convincing differences between Mediterranean and low fat programmes for mortality or non-fatal myocardial infarction. The five remaining dietary programmes generally had little or no benefit compared with minimal intervention typically based on low to moderate certainty evidence. CONCLUSIONS: Moderate certainty evidence shows that programmes promoting Mediterranean and low fat diets, with or without physical activity or other interventions, reduce all cause mortality and non-fatal myocardial infarction in patients with increased cardiovascular risk. Mediterranean programmes are also likely to reduce stroke risk. Generally, other named dietary programmes were not superior to minimal intervention. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016047939.


Subject(s)
Cardiovascular Diseases , Myocardial Infarction , Stroke , Humans , Cardiovascular Diseases/prevention & control , Network Meta-Analysis , Risk Factors , Myocardial Infarction/prevention & control , Stroke/prevention & control , Diet, Fat-Restricted
3.
BMC Infect Dis ; 22(1): 917, 2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36482326

ABSTRACT

BACKGROUND: Despite the development and application of vaccines against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) around the world, the scientific community is still trying to find some therapies to avoid or ameliorate the fatal evolution of the Coronavirus disease 2019 (COVID-19). Since the publication of the potential use of ivermectin as a treatment against the disease, a pleiad of information about it has been published. However, the evidence is not strong or weak enough to conclude its usefulness in the clinical evolution of patients infected with SARS-CoV-2. We evaluate the efficacy and safety of ivermectin in the treatment of Mexican patients with asymptomatic and mild COVID-19 in a three-day administration in comparison to placebo. METHODS: A randomized, double-blind, placebo-controlled trial was carried out in 66 adults with asymptomatic and mild COVID-19. Patients were randomly assigned 1:1 ratio to ivermectin plus acetaminophen or placebo plus acetaminophen. The primary endpoint was the proportion of subjects without a disease progression to severity according to COVID-19 guidelines by the National Institutes of Health (NIH) since randomization to 14 days. RESULTS: None of the participants presented progression to a severe state in either group. Viral load was measured on Days 1, 5, and 14. No significant differences were observed in baseline or 14-day between groups (p = 0.720 and 0.362, respectively). However, on Day 5, a significant difference in viral load was observed between groups (p = 0.039). The frequency of symptoms was similar between groups, and no significant differences were observed. The most frequent symptom was cough. One severe adverse event associated with SARS-CoV-2 infection was observed in the ivermectin group. CONCLUSIONS: At standard doses, ivermectin is not effective to prevent progression to a severe state or reducing symptoms in adults with asymptomatic and mild COVID-19. Trial registration The study was registered with ClinicalTrial.gov (NCT04407507) on May 29, 2020.


Subject(s)
COVID-19 , Ivermectin , Humans , Disease Progression , Ivermectin/therapeutic use , SARS-CoV-2 , United States
4.
Diagnostics (Basel) ; 12(6)2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35741242

ABSTRACT

The aim of this study was to use cone-beam computed tomography (CBCT) to evaluate the morphometric properties of the interradicular septum (IRS) in the maxillary molar region that may be indicative for prosthetic-driven implant placement. Following the repetitive algorithm based on the visual identification of IRS shapes, we described the following IRS shapes: arrow, boat, drop, and palatal and buccal convergence. The incidence of IRS shapes showed significant differences for the first and second maxillary molars (the highest frequency for the arrow shape, and the lowest for the drop shape) with no significant difference between the molars. The most prominent width indicative for implant placement was observed in the palatal convergence shape, whereas the height criteria were the most satisfying in the buccal convergence-shaped IRS for both molars. Apart from the parameters in the coronal view, the image analysis in the axial view revealed that IRS surface area, required for the implant placement, was the most prominent in the palatal convergence shape for the first, and boat shape for the second molars. Our results showed the benefits of CBCT diagnostics in posterior maxilla morphometric analysis. IRS shape classification may be helpful in achieving more rapid and accurate planning for interventions in this region.

5.
Oxid Med Cell Longev ; 2021: 8207283, 2021.
Article in English | MEDLINE | ID: mdl-34447488

ABSTRACT

The aim of this study was to investigate and compare the systemic toxicity of three nanosized calcium phosphates (CaPs): hydroxyapatite (HA), tricalcium phosphate (TCP), and amorphous calcium phosphate (ACP) in rats. Since those metallic compounds are widely used as bone replacement materials, including their use in oral surgery, CaPs were applied (per os) equimollary (17.8 mg/kg, 11 mg/kg, and 9.65 mg/kg b.w., respectively) for 30 days in order to mimic the previously described release rate from dental composites. Also, we employed antioxidant supplementation with Filipendula ulmaria (FU) extract. All the applied CaPs significantly increased serum calcium, triglycerides, LDL, and LDH, while serum levels of testosterone and LH declined, with no alterations in the liver enzymes. The evaluation of oxidative stress markers (in the liver, kidney, and testicle) showed an increase in TBARS values, while SOD and CAT activities and GSH levels were significantly reduced. The relative gene expression of Bax and Bcl-2 was shifted to proapoptotic action, accompanied by intense characteristic histological changes in architecture in all investigated organs. The toxic effects were most prominent in groups treated by ACP. FU administration attenuated the majority of nanosized CaP-induced adverse effects, thus recommending this therapeutic approach to minimize nano-CaP systemic toxicities.


Subject(s)
Antioxidants , Calcium Phosphates/adverse effects , Filipendula/chemistry , Nanostructures/adverse effects , Plant Extracts , Animals , Antioxidants/chemistry , Antioxidants/pharmacology , Calcium Phosphates/pharmacology , Male , Plant Extracts/chemistry , Plant Extracts/pharmacology , Rats , Rats, Wistar
6.
Antibiotics (Basel) ; 10(5)2021 May 08.
Article in English | MEDLINE | ID: mdl-34066788

ABSTRACT

The worldwide problem of infectious diseases has appeared in recent years, and antimicrobial agents are crucial in reducing disease emergence. Nevertheless, the development and distribution of multidrug-resistant (MDR) strains in pathogenic bacteria, such as Escherichia coli, Staphylococcus aureus, Salmonella Typhi and Citrobacter koseri, has become a major society health hazard. Essential oils could serve as a promising tool as a natural drug in fighting the problem with these bacteria. The current study aimed to investigate the antimicrobial effectiveness of tea tree (Melaleuca alternifolia (Maiden and Betche) Cheel), rosemary (Rosmarinus officinalis L.), eucalyptus (Eucalyptus obliqua L'Hér.), and lavender (Lavandula angustifolia Mill) essential oils. The antimicrobial properties of essential oils were screened against four pathogenic bacteria, E. coli, S. aureus, S. Tyhpi, and C. koseri, and two reference bacterial strains, while for the testing, the agar well diffusion method was used. Gas chromatography (GC) and gas chromatography-mass spectrometric (GC-MSD) analyses were performed on essential oils. The obtained results showed that M. alternifolia essential oil is the richest in terpinen-4-ol, R. officinalis and E. oblique essential oils in 1,8-cineole, and L. angustifolia essential oil in α-terpinyl acetate. In addition, the main bioactive compounds present in the essential oil of tea tree are rich in α-pinene (18.38%), limonene (7.55%) and γ-terpinene (14.01%). The essential oil of rosemary is rich in α-pinene (8.38%) and limonene (11.86%); eucalyptus essential oil has significant concentrations of α-pinene (12.60%), p-cymene (3.24%), limonene (3.87%), and γ-terpinene (7.37%), while the essential oil of lavender is rich in linalool (10.71%), linalool acetate (9.60%), α-terpinyl acetate (10.93%), and carbitol (13.05%) bioactive compounds, respectively. The obtained results from the in vitro study revealed that most of the essential oils exhibited antimicrobial properties. Among the tested essential oils, tea tree was discovered to demonstrate the strongest antimicrobial activity. The recorded MIC of S. Typhi was 6.2 mg/mL, 3.4 mg/mL of C. koseri, 3.1 mg/mL of E. coli, and 2.7 mg/mL of E. coli ATCC 25922, compared to M. alternifolia. Similarly, only S. aureus ATCC 25923 showed antimicrobial activity towards R. officinalis (1.4 mg/mL), E. oblique (2.9 mg/mL), and L. angustifolia (2.1 mg/mL). Based on the obtained results, it is possible to conclude that tea tree essential oil might be used as an ecological antimicrobial in treating infectious diseases caused by the tested pathogens.

7.
Oxid Med Cell Longev ; 2021: 6670135, 2021.
Article in English | MEDLINE | ID: mdl-33628375

ABSTRACT

Mineral components of dental composites are used in many medical and dental applications, including preventive, restorative, and regenerative dentistry. To evaluate the behavioural alterations induced by nanosized particles of novel dental composites, by means of depressive level and cognitive functions, experimental groups of rats were chronically administered with nanosized hydroxyapatite (HA), tricalcium phosphate (TCP), and amorphous calcium phosphate (ACP) with or without simultaneous application of Filipendula ulmaria L. (FU) methanolic extract. The significant prodepressant action was observed in groups solely treated with HA and ACP. Besides, prolonged treatment with ACP also resulted in a significant decline in cognitive functions estimated in the novel object recognition test. The adverse impact of calcium phosphates on estimated behavioural functions was accompanied by increased oxidative damage and apoptotic markers in the prefrontal cortex, as well as diminished specific neurotrophin (BDNF) and gabaergic expression. The results of our investigation showed that simultaneous antioxidant supplementation with FU extract prevented calcium phosphate-induced behavioural disturbances, as well as prooxidative and apoptotic actions, with the simultaneous restoration of BDNF and GABA-A receptors in the prefrontal cortex. These findings suggest that FU may be useful in the prevention of prodepressant impact and cognitive decline as early as the manifestation of calcium phosphate-induced neurotoxicity.


Subject(s)
Calcium Phosphates/toxicity , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/prevention & control , Depression/drug therapy , Depression/prevention & control , Filipendula/chemistry , Nanoparticles/toxicity , Plant Extracts/therapeutic use , Animals , Apoptosis/drug effects , Apoptosis/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cognitive Dysfunction/complications , Cognitive Dysfunction/genetics , Depression/complications , Depression/genetics , Gene Expression Regulation/drug effects , Hindlimb Suspension , Male , Open Field Test , Oxidative Stress/drug effects , Oxidative Stress/genetics , Plant Extracts/pharmacology , Rats, Wistar , gamma-Aminobutyric Acid/metabolism
8.
J Integr Neurosci ; 20(4): 871-883, 2021 Dec 30.
Article in English | MEDLINE | ID: mdl-34997711

ABSTRACT

We evaluated the influence of an antioxidant-rich extract of Filipendula ulmaria L. on anxiety levels induced by nano-sized particles of different calcium phosphates. Rats in experimental groups were administered with either nano-sized hydroxyapatite, tricalcium phosphate, or amorphous calcium phosphate in the presence of Filipendula ulmaria extract. Appropriate behavioral tests were performed to assess anxiety levels, while oxidative status and apoptosis parameters were determined in the hippocampus samples. The applied calcium phosphates increased oxidative stress markers in hippocampal tissue, accompanied by an enhanced pro-apoptotic mechanism. Moreover, the hippocampal immunoreactivity for brain-derived neurotrophic factor and GABAergic-A receptors was significantly lower following calcium phosphate nanoparticles intake. The observed functional and morphological alterations in the rat hippocampus occurred simultaneously with the anxiogenic response estimated in behavioral testing. The neuroprotective effect of Filipendula ulmaria was markedly manifested by the attenuation of oxidative damage induced by amorphous calcium phosphate and enhanced anti-apoptotic action in the rat hippocampus. The increased hippocampal immunoreactivity for brain-derived neurotrophic factor, GABAergic-A receptors and significant anxiolytic-like effects of Filipendula ulmaria may suggest a beneficial role of antioxidant supplementation in preventing anxiogenic response to nano-sized calcium phosphates.


Subject(s)
Antioxidants/pharmacology , Anxiety/drug therapy , Apoptosis/drug effects , Filipendula , Hippocampus/drug effects , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Animals , Anxiety/chemically induced , Behavior, Animal/drug effects , Calcium Phosphates/administration & dosage , Male , Nanoparticles/administration & dosage , Rats , Rats, Wistar
9.
J Med Econ ; 23(9): 932-939, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32349564

ABSTRACT

Background: The pharmaceutical industry in the countries of Southeast Europe is still underdeveloped. Despite experience and tradition as well as significant research efforts and innovation potential, there are still big differences among the companies in the pharmaceutical sector of the SEE countries. It is for this reason that the subject of the study is the analysis of the comparative advantage in exports of the pharmaceutical sector of the SEE countries.Aim: The aim is to point out the potential of the sector and the directions of its development. The study also aims to define the position of the pharmaceutical sector in the SEE countries in today's global context. The study has comprised the pharmaceutical products belonging to group 30 in the HS6 classification and SITC 54 classification in the period 2005-2018.Conclusions: The results of the study indicate that the SEE countries have negative comparative advantage in exports, in the analysed period, except for Slovenia, which stands out with positive values of the RCA index. The products, dominating the foreign trade of the SEE pharmaceutical sector, belong to the group of Medicaments consisting of mixed or unmixed products for therapeutic or prophylactic uses.


Subject(s)
Drug Industry/organization & administration , Economic Competition/organization & administration , Drug Industry/economics , Employment , Europe, Eastern , Humans , Taxes
10.
J Pharm Sci ; 106(3): 850-858, 2017 03.
Article in English | MEDLINE | ID: mdl-27964902

ABSTRACT

Alternate geometries of a commercial dry powder inhaler (DPI, i.e., Turbuhaler; AstraZeneca, London, UK) are proposed based on the simulation results obtained from a fluid and particle dynamic computational model, previously developed by Milenkovic et al. The alternate DPI geometries are constructed by simple alterations to components of the commercial inhaler device leading to smoother flow patterns in regions where significant particle-wall collisions occur. The modified DPIs are investigated under the same conditions of the original studies of Milenkovic et al. for a wide range of inhalation flow rates (i.e., 30-70 L/min). Based on the computational results in terms of total particle deposition and fine particle fraction, the modified DPIs were improved over the original design of the commercial device.


Subject(s)
Dry Powder Inhalers/instrumentation , Dry Powder Inhalers/standards , Equipment Design/instrumentation , Equipment Design/standards , Technology, Pharmaceutical/instrumentation , Technology, Pharmaceutical/standards , Administration, Inhalation , Particle Size
11.
Cardiol Young ; 25(3): 520-5, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24666760

ABSTRACT

UNLABELLED: Physical activity tends to be lower in school-age children with congenital heart disease than in healthy controls. To the best of our knowledge, objectively measured physical activity levels of preschool-age children with congenital heart disease have not been studied. METHODS: A total of 10 children with either coarctation of the aorta (n=6; age 3.8±0.9) or tetralogy of Fallot (n=4, age 4.3±0.9) were recruited from the cardiology unit of McMaster Children's Hospital. Height (103.7±8.2 cm) and weight (17.3±2.7 kg) measurements were recorded, and physical activity was determined using accelerometry over 7 consecutive days. Patients were compared with age-, sex-, and season of data acquisition-matched controls. Parents completed a questionnaire regarding the child's physical activity and sedentary behaviours. RESULTS: Patients spent on average 219.4±39.9 minutes engaged in total physical activity per day at the following intensities: light, 147.5±22.3; moderate, 44.0±11.8; moderate-to-vigorous, 71.9±22.6; and vigorous, 27.9±11.7. No significant differences were observed between patients and controls for total physical activity (p=0.80) or any of the intensities (p=0.71, 0.46, 0.43, and 0.45, respectively). Only 40% of patients and controls met the new Canadian Physical Activity Guidelines for the Early Years of at least 180 minutes of physical activity at any intensity every day. Of the patients' parents, 90% believed that their child was as active, if not more active, than his/her siblings, and 80% of parents reported their child spending 1-3 hours in screen time activities daily. CONCLUSION: Children aged 3-5 years old with congenital heart disease have comparable physical activity levels to age-, sex-, and season-matched controls, and many do not meet Canadian Physical Activity Guidelines.


Subject(s)
Heart Defects, Congenital/physiopathology , Motor Activity/physiology , Accelerometry/methods , Aortic Coarctation/physiopathology , Case-Control Studies , Child , Child, Preschool , Female , Humans , Male , Tetralogy of Fallot/physiopathology , Time Factors
12.
Anal Biochem ; 346(1): 101-6, 2005 Nov 01.
Article in English | MEDLINE | ID: mdl-16168380

ABSTRACT

Advanced glycation end products (AGEs) that arise from the reaction of sugars with protein side chains are supposed to be involved in the pathogenesis of several diseases; therefore, the effects of AGEs on cells are the objective of numerous investigations. Because AGE modifications are an extremely heterogeneous group of side chain modifications, the exact characterization of an AGE-modified protein is impossible. To gain a deeper understanding about AGE formation kinetics and structures, AGEs can be characterized with respect to the degree of modification, specific side chain modifications, absorbance and fluorescence characteristics, and changes in the protein structure and molecular weight. For this study, human serum albumin (HSA)-AGEs derived from different concentrations of glucose, methyl glyoxal, and glyoxylic acid were used. The molecular mass of the obtained AGEs was determined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The mass data were compared with earlier results concerning the degree of lysine and arginine side chain modifications and AGE-specific fluorescence and absorbance data. The molecular masses were found to gradually increase with increasing concentrations of the individual modifier without reaching a plateau. The mass increase correlates very well with the AGE-specific absorbance at 360 nm and with the degree of side chain modifications. The mass spectrometric data prove, for the first time, that an increasing absorbance at 360 nm is directly correlated to a mass increase during the AGE formation process.


Subject(s)
Glycation End Products, Advanced/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
13.
J Neurochem ; 87(1): 44-55, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12969251

ABSTRACT

Deposition of cross-linked insoluble protein aggregates such as amyloid plaques is characteristic for Alzheimer's disease. Microglial activation by these extracullar deposits has been proposed to play a crucial role in functional degeneration as well as cell death of neurones. A sugar-derived post-translational modification of long-lived proteins, advanced glycation endproducts (AGEs), activate specific signal transduction pathways, resulting in the up-regulation of various pro-inflammatory signals such as cytokines [interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha)] and inducible nitric oxide synthase (iNOS). Our goal was to study AGE-activated signal transduction pathways involved in the induction of pro-inflammatory effectors in the murine microglial cell line N-11. Chicken egg albumin-AGE (CEA-AGE), used as model AGE, induces nitric oxide (NO), TNF-alpha and IL-6 production. The AGE receptor, RAGE, and the transcription factor, nuclear factor kappa B (NF-kappaB), appear to be involved in all pathways, since a neutralizing RAGE antibody and a peptide inhibiting NF-kappaB translocation down-regulated NO, TNF-alpha and IL-6 production. NO and TNF-alpha, but not IL-6 production appear to be regulated independently, since NOS inhibitors did not decrease TNF-alpha secretion and a neutralizing TNF-alpha antibody did not reduce NO production, while employment of NOS inhibitors reduced significantly the secretion of IL-6. Inhibition of the MAP-kinase-kinase (MEK) and phosphatidylinositol 3-kinase (PI3K) pathway, but not that of mitogen-activated protein kinase-p38 (MAPK-p38), reduced NO, TNF-alpha and IL-6 significantly, suggesting that simultaneous activation of the first two pathways is necessary for the AGE-induced induction of these pro-inflammatory stimuli.


Subject(s)
Glycation End Products, Advanced/pharmacology , Microglia/drug effects , Microglia/metabolism , Signal Transduction/physiology , Albumins/chemistry , Animals , Antibodies/pharmacology , Cell Line , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Glucose/chemistry , Glycation End Products, Advanced/chemical synthesis , Interleukin-6/biosynthesis , Mice , Microglia/cytology , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/antagonists & inhibitors , NF-kappa B/antagonists & inhibitors , Nitric Oxide/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation/drug effects , Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor for Advanced Glycation End Products , Receptors, Immunologic/antagonists & inhibitors , Receptors, Immunologic/metabolism , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/biosynthesis , p38 Mitogen-Activated Protein Kinases
14.
Exp Brain Res ; 150(1): 1-8, 2003 May.
Article in English | MEDLINE | ID: mdl-12698210

ABSTRACT

Activation of glial cells has been proposed to contribute to neuronal dysfunction and neuronal cell death in Alzheimer's disease. In this study, we attempt to determine some of the effects of secreted factors from activated murine N-11 microglia on viability and morphology of neurons using the differentiated neuroblastoma cell line Neuro2a. Microglia were activated either by lipopolysaccharide (LPS), bacterial cell wall proteoglycans, or advanced glycation endproducts (AGEs), protein-bound sugar oxidation products. At high LPS or AGE concentrations, conditioned medium from microglia caused neuronal cell death in a dose-dependent manner. At sublethal LPS or AGE concentrations, conditioned media inhibited retinoic acid-induced neurite outgrowth and stimulated retraction of already extended neurites. Among the many possible secreted factors, the contribution of NO or NO metabolites in the cytotoxicity of conditioned medium was investigated. Cell death and changes in neurite morphology were partly reduced when NO production was inhibited by nitric oxide synthase inhibitors. The results suggest that even in the absence of significant cell death, inflammatory processes, which are partly transmitted via NO metabolites, may affect intrinsic functions of neurons such as neurite extension that are essential components of neuronal morphology and thus may contribute to degenerative changes in Alzheimer's disease.


Subject(s)
Alzheimer Disease/metabolism , Cell Death/physiology , Cell Survival/physiology , Gliosis/metabolism , Microglia/metabolism , Neurites/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/physiopathology , Animals , Cell Death/drug effects , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Survival/drug effects , Culture Media, Conditioned/pharmacology , Dose-Response Relationship, Drug , Gliosis/pathology , Gliosis/physiopathology , Glycation End Products, Advanced , Inflammation/metabolism , Inflammation/pathology , Inflammation/physiopathology , Lipopolysaccharides , Mice , Microglia/cytology , Microglia/drug effects , Neurites/drug effects , Neurites/ultrastructure , Neuroblastoma , Nitric Oxide/metabolism , Proteoglycans , Tretinoin/pharmacology , Tumor Cells, Cultured
15.
J Alzheimers Dis ; 5(1): 25-30, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12590163

ABSTRACT

Advanced glycation endproducts (AGEs), sugar-derived protein modifications and lipid peroxidation products are prominent features of Alzheimer's disease. AGEs accumulate on beta-amyloid plaques during the course of the disease and can exert chronic oxidative stress via receptor-mediated mechanisms. Lipid peroxidation products such as hydroxynonenal, further markers of oxidative stress, are also increased in Alzheimer's diesease. In this study we present evidence for a direct biochemical link between AGEs and lipid peroxidation. Our results show that AGEs induce lipid peroxidation in a neuronal cell line in a dose-dependant manner, and that blocking the specific AGE-receptor RAGE, as well as using different antioxidants (alpha-lipoic acid, N-acetylcysteine, 17 beta-estradiol or aminoguanidine) can reduce the AGE-mediated formation of lipid peroxidation products. Thus, both RAGE antagonists and scavengers of oxygen free radicals could be useful in protecting brain tissue from lipid peroxidation and its pathophysilogical consequences that occur in Alzheimer's disease.


Subject(s)
Acetylcysteine/pharmacology , Estradiol/pharmacology , Glycation End Products, Advanced/metabolism , Lipid Peroxidation/drug effects , Neurons/metabolism , Neurons/pathology , Thioctic Acid/pharmacology , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Brain/drug effects , Brain/metabolism , Brain/pathology , Cells, Cultured , Free Radicals/antagonists & inhibitors , Humans , Oxidative Stress/drug effects , Signal Transduction/drug effects
16.
Eur J Neurosci ; 17(4): 813-21, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12603271

ABSTRACT

beta-Amyloid (Abeta) plaques are characteristic hallmarks of Alzheimer's disease (AD). In AD, it has been suggested that activation of microglial cells might be the link between Abeta deposition and neuronal degeneration. Activated microglia are associated with senile plaques and produce free radicals and inflammatory cytokines. However, it is still not clear whether Abeta needs a prestimulated environment to exert its proinflammatory potential. Advanced glycation endproducts (AGEs), protein-bound oxidation products of sugars, have been shown to accumulate in senile plaques and could induce a silent but chronic inflammation in the AD brain. We tested whether Abeta acts as an amplifier of a submaximal proinflammatory response initiated by exposure to chicken egg albumin-AGE, lipopolysaccharide or interferon-gamma. Synthetic Abeta was used to produce three different samples (Abeta-fibrilar; Abeta-aggregated; Abeta-AGE), which were characterized for beta-sheeted fibrils by the thioflavin-T test and electron microscopy. As markers of microglial activation, nitric oxide, interleukin-6, macrophage-colony stimulation factor and tumour necrosis factor-alpha production was measured. All three Abeta samples alone could not induce a detectable microglial response. The combination of Abeta preparations, however, with the coinducers provoked a strong microglial response, whereby Abeta-AGE and fibrilar Abeta were more potent inflammatory signals than aggregated Abeta. Thus, Abeta in senile plaques can amplify microglial activation by a coexisting submaximal inflammatory stimulus. Hence, anti-inflammatory therapeutics could either target the primary proinflammatory signal (e.g. by limiting AGE-formation by AGE inhibitors or cross-link breakers) or the amplifyer Abeta (e.g. by limiting Abeta production by beta- or gamma-secretase inhibitors).


Subject(s)
Amyloid beta-Peptides/pharmacology , Glycation End Products, Advanced/pharmacology , Inflammation/etiology , Interferon-gamma/pharmacology , Lipopolysaccharides/pharmacology , Microglia/drug effects , Peptide Fragments/pharmacology , Amyloid/ultrastructure , Amyloid beta-Peptides/chemistry , Animals , Cell Line , Cell Survival , Dose-Response Relationship, Drug , Drug Synergism , Inflammation/metabolism , Inflammation/physiopathology , Interleukin-6/metabolism , Macrophage Colony-Stimulating Factor/metabolism , Mice , Microglia/cytology , Microscopy, Electron/methods , Nitric Oxide/metabolism , Peptide Biosynthesis , Peptide Fragments/chemistry , Plaque, Amyloid/ultrastructure , Tumor Necrosis Factor-alpha/metabolism
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