scholarly journals O-Vanillin Attenuates the TLR2 Mediated Tumor-Promoting Phenotype of Microglia

2020 ◽  
Vol 21 (8) ◽  
pp. 2959
Author(s):  
Paul Triller ◽  
Julia Bachorz ◽  
Michael Synowitz ◽  
Helmut Kettenmann ◽  
Darko Markovic
Keyword(s):  
Malignant Gliomas ◽  
Experimental Models ◽  
Brain Macrophages ◽  
Human Microglia ◽  
Glioma Growth ◽  
Toll Like Receptor 2 ◽  
Brain Slice Cultures ◽  
The Impact

Malignant gliomas are primary brain tumors with poor prognoses. These tumors are infiltrated by brain intrinsic microglia and peripheral monocytes which promote glioma cell invasion. In our previous studies, we discovered that the activation of Toll-like receptor 2 (TLR2) on microglia/brain macrophages converts them into a protumorigenic phenotype through the induction of matrix metalloproteinases (MMP) 9 and 14. In the present study, we used in vitro and in situ microglia-glioma interaction experimental models to test the impact of a novel inhibitor of TLR 2, ortho vanillin (O-Vanillin) to block TLR2 mediated microglia protumorigenic phenotype. We demonstrate that O-Vanillin inhibits the TLR2 mediated upregulation of MMP 9, MMP 14, IL 6 and iNOS expression. Similarly, the glioma supernatant induced MMP 9 and MMP 14 expression in murine and human microglia is abrogated by O-Vanillin treatment. O-Vanillin is not toxic for microglia, astrocytes or oligodendrocytes. Glioma growth in murine brain slice cultures is significantly reduced after treatment with O-Vanillin, and this reduced glioma growth depends on the presence of microglia. In addition, we also found that O-Vanillin inhibited the glioma induced proliferation of murine primary microglia. In summary, O-Vanillin attenuates the pro-tumorigenic phenotype of microglia/brain macrophages and thus qualifies as a candidate for glioma therapy.

scholarly journals Doxorubicin-Induced Translocation of mtDNA into the Nuclear Genome of Human Lymphocytes Detected Using a Molecular-Cytogenetic Approach

2020 ◽  
Vol 21 (20) ◽  
pp. 7690
Author(s):  
Tigran Harutyunyan ◽  
Ahmed Al-Rikabi ◽  
Anzhela Sargsyan ◽  
Galina Hovhannisyan ◽  
Rouben Aroutiounian ◽  
...  
Keyword(s):  
Human Lymphocytes ◽  
Nuclear Genome ◽  
Biological Phenomenon ◽  
Molecular Cytogenetic ◽  
Chromosome Breaks ◽  
Pathological Conditions ◽  
The Impact ◽  
In Vitro Treatment

Translocation of mtDNA in the nuclear genome is an ongoing process that contributes to the development of pathological conditions in humans. However, the causal factors of this biological phenomenon in human cells are poorly studied. Here we analyzed mtDNA insertions in the nuclear genome of human lymphocytes after in vitro treatment with doxorubicin (DOX) using a fluorescence in situ hybridization (FISH) technique. The number of mtDNA insertions positively correlated with the number of DOX-induced micronuclei, suggesting that DOX-induced chromosome breaks contribute to insertion events. Analysis of the odds ratios (OR) revealed that DOX at concentrations of 0.025 and 0.035 µg/mL significantly increases the rate of mtDNA insertions (OR: 3.53 (95% CI: 1.42–8.76, p < 0.05) and 3.02 (95% CI: 1.19–7.62, p < 0.05), respectively). Analysis of the distribution of mtDNA insertions in the genome revealed that DOX-induced mtDNA insertions are more frequent in larger chromosomes, which are more prone to the damaging action of DOX. Overall, our data suggest that DOX-induced chromosome damage can be a causal factor for insertions of mtDNA in the nuclear genome of human lymphocytes. It can be assumed that the impact of a large number of external and internal mutagenic factors contributes significantly to the origin and amount of mtDNA in nuclear genomes.

scholarly journals Comparison of In Vitro and In Situ Methods for Studying Lipolysis

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Ahmad Ghorbani ◽  
Mahmood Abedinzade
Keyword(s):  
Metabolic Syndrome ◽  
Nervous System ◽  
Adipose Tissue ◽  
Organ Culture ◽  
Experimental Methods ◽  
Experimental Models ◽  
Autocrine Factors ◽  
In Situ Methods

Lipolysis is a highly regulated process and is controlled by nervous system, hormones, and paracrine/autocrine factors. Dysregulation of lipolysis is associated with some pathophysiological conditions including diabetes, metabolic syndrome, and obesity. Nowadays, special attention isthereforepaid to study lipolysis using different experimental models. This review summarizes the current experimental methods for studying lipolysis. Culture of preadipocyte cell lines, use of differentiated stroma-vascular cells, primary culture of adipocyte, organ culture of adipose tissue, and microdialysis technique are the most widely used techniques to study lipolysis. The advantages and limitations of using these methods are discussed.

Evidence for the Usefulness of in vitro Dialyzability, Caco-2 Cell Models, Animal Models, and Algorithms to Predict Zinc Bioavailability in Humans

2005 ◽  
Vol 75 (6) ◽  
pp. 423-435 ◽  
Author(s):  
Christine Hotz
Keyword(s):  
Animal Models ◽  
Experimental Models ◽  
Dietary Factors ◽  
Human Organism ◽  
Zinc Absorption ◽  
In Vitro Methods ◽  
Zinc Bioavailability ◽  
Zinc Retention ◽  
The Impact

Low bioavailability of zinc in certain diet types may contribute to zinc deficiency and its consequences in populations. As a result, several experimental models including animal models, in vitro dialyzability models, and Caco-2 cells, have been used to study these factors and estimate their impact on human zinc absorption. For the most part, consistency has been observed between the latter models and human absorption studies to identify factors that enhance or inhibit zinc bioavailability. However, dialyzability methods are limited to modeling luminal interactions among the factors as they affect zinc availability while Caco-2 cells can model luminal effects and uptake by intestinal cells. Neither animal nor in vitro methods can predict the magnitude of zinc absorption at the level of the human organism. Caco-2 cells will be useful models for understanding the mechanisms of intestinal zinc absorption. The in vitro methods are also limited to modeling absorption and the interactions that occur. Algorithms to estimate zinc absorption, based on dietary content of zinc absorption modifiers, have been derived from human studies. An algorithm derived from studies of zinc retention from radioactive zinc-labeled test meals underestimates zinc absorption compared to that derived from measurement of true zinc absorption from total diets using isotopic tracer methods. Based on the latter, phytate appears to be the only major inhibitor of zinc absorption from typical diets. Ultimately, population-based studies are needed to determine the impact of dietary factors that modulate zinc absorption on the adequacy of zinc status.

scholarly journals Chemical Composition, In Vitro and In Situ Antimicrobial and Antibiofilm Activities of Syzygium aromaticum (Clove) Essential Oil

Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2185
Author(s):  
Miroslava Kačániová ◽  
Lucia Galovičová ◽  
Petra Borotová ◽  
Veronika Valková ◽  
Hana Ďúranová ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oil ◽  
Mass Spectra ◽  
Control Sample ◽  
Antibiofilm Activity ◽  
Syzygium Aromaticum ◽  
Food Preservatives ◽  
The Impact

The essential oil of Syzygium (S.) aromaticum (CEO) is known for its good biological activity. The aim of the research was to evaluate in vitro and in situ antimicrobial and antibiofilm activity of the essential oil produced in Slovakia. The main components of CEO were eugenol 82.4% and (E)-caryophyllene 14.0%. The antimicrobial activity was either weak or very strong with inhibition zones ranging from 4.67 to 15.78 mm in gram-positive and gram-negative bacteria and from 8.22 to 18.56 mm in yeasts and fungi. Among the tested bacteria and fungi, the lowest values of MIC were determined for Staphylococcus (S.) aureus and Penicillium (P.) expansum, respectively. The vapor phase of CEO inhibited the growth of the microscopic filamentous fungi of the genus Penicillium when tested in situ on bread. The strongest effect of mycelia inhibition in a bread model was observed against P. expansum at concentrations of 250 and 500 μL/mL. The best antimicrobial activity of CEO in the carrot model was found against P. chrysosenum. Differences between the mass spectra of Bacillus (B.) subtilis biofilms on the tested surfaces (wood, glass) and the control sample were noted from the seventh day of culture. There were some changes in mass spectra of Stenotrophomonas (S.) maltophilia, which were observed in both experimental groups from the fifth day of culture. These findings confirmed the impact of CEO on the protein structure of older biofilms. The findings indicate that, besides being safe and sensorially attractive, S. aromaticum has antimicrobial activity, which makes it a potential substitute for chemical food preservatives.

scholarly journals Phagocytosis and Efferocytosis by Resident Macrophages in the Mouse Pancreas

2021 ◽  
Vol 12 ◽  
Author(s):  
Kristel Parv ◽  
Nestori Westerlund ◽  
Kevin Merchant ◽  
Milad Komijani ◽  
Robin S. Lindsay ◽  
...  
Keyword(s):  
Confocal Imaging ◽  
Mouse Pancreas ◽  
Tissue Microenvironment ◽  
Inflammatory State ◽  
Islet Dysfunction ◽  
Diabetes Development ◽  
The Impact

The tissue microenvironment in the mouse pancreas has been shown to promote very different polarizations of resident macrophages with islet-resident macrophages displaying an inflammatory “M1” profile and macrophages in the exocrine tissue mostly displaying an alternatively activated “M2” profile. The impact of this polarization on tissue homeostasis and diabetes development is unclear. In this study, the ability of pancreas-resident macrophages to phagocyte bacterial and endogenous debris was investigated. Mouse endocrine and exocrine tissues were separated, and tissue-resident macrophages were isolated by magnetic immunolabeling. Isolated macrophages were subjected to flow cytometry for polarization markers and qPCR for phagocytosis-related genes. Functional in vitro investigations included phagocytosis and efferocytosis assays using pH-sensitive fluorescent bacterial particles and dead fluorescent neutrophils, respectively. Intravital confocal imaging of in situ phagocytosis and efferocytosis in the pancreas was used to confirm findings in vivo. Gene expression analysis revealed no significant overall difference in expression of most phagocytosis-related genes in islet-resident vs. exocrine-resident macrophages included in the analysis. In this study, pancreas-resident macrophages were shown to differ in their ability to phagocyte bacterial and endogenous debris depending on their microenvironment. This difference in abilities may be one of the factors polarizing islet-resident macrophages to an inflammatory state since phagocytosis has been found to imprint macrophage heterogeneity. It remains unclear if this difference has any implications in the development of islet dysfunction or autoimmunity.

scholarly journals Soluble α-synuclein–antibody complexes activate the NLRP3 inflammasome in hiPSC-derived microglia

2021 ◽  
Vol 118 (15) ◽  
pp. e2025847118
Author(s):  
Dorit Trudler ◽  
Kristopher L. Nazor ◽  
Yvonne S. Eisele ◽  
Titas Grabauskas ◽  
Nima Dolatabadi ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Amyloid Β ◽  
Induced Pluripotent Stem Cell ◽  
Amyloid Β Peptide ◽  
Human Microglia ◽  
Pyrin Domain ◽  
Toll Like Receptor 2 ◽  
Induced Pluripotent

Parkinson’s disease is characterized by accumulation of α-synuclein (αSyn). Release of oligomeric/fibrillar αSyn from damaged neurons may potentiate neuronal death in part via microglial activation. Heretofore, it remained unknown if oligomeric/fibrillar αSyn could activate the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome in human microglia and whether anti-αSyn antibodies could prevent this effect. Here, we show that αSyn activates the NLRP3 inflammasome in human induced pluripotent stem cell (hiPSC)-derived microglia (hiMG) via dual stimulation involving Toll-like receptor 2 (TLR2) engagement and mitochondrial damage. In vitro, hiMG can be activated by mutant (A53T) αSyn secreted from hiPSC-derived A9-dopaminergic neurons. Surprisingly, αSyn–antibody complexes enhanced rather than suppressed inflammasome-mediated interleukin-1β (IL-1β) secretion, indicating these complexes are neuroinflammatory in a human context. A further increase in inflammation was observed with addition of oligomerized amyloid-β peptide (Aβ) and its cognate antibody. In vivo, engraftment of hiMG with αSyn in humanized mouse brain resulted in caspase-1 activation and neurotoxicity, which was exacerbated by αSyn antibody. These findings may have important implications for antibody therapies aimed at depleting misfolded/aggregated proteins from the human brain, as they may paradoxically trigger inflammation in human microglia.

scholarly journals Application of Plant Extracts for the Prevention of Dental Erosion: An in situ/in vitro Study

2015 ◽  
Vol 49 (5) ◽  
pp. 477-487 ◽  
Author(s):  
Marie-Theres Weber ◽  
Matthias Hannig ◽  
Sandra Pötschke ◽  
Franziska Höhne ◽  
Christian Hannig
Keyword(s):  
Plant Extracts ◽  
Dental Erosion ◽  
Oral Exposure ◽  
Wild Form ◽  
Dependent Manner ◽  
Mouth Rinse ◽  
Protective Properties ◽  
The Impact

Objectives: Antiadherent and antibacterial effects of certain plant extracts have been proven to be beneficial in preventive dentistry. In the present in situ/in vitro crossover study, the impact of plant extracts rich in polyphenols on the erosion-protective properties of the in situ pellicle was evaluated. Methods: Individual splints were prepared for 12 subjects for intraoral exposure of bovine enamel specimens. Following formation of a 1-min pellicle, watery plant extracts (leaves of the wild form of Ribes nigrum, the wild form of Origanum as well as a combination of both) were administered for 10 min in situ. Alternatively, a mouth rinse with fluorides (Elmex Kariesschutz) was performed for 1 min. After further oral exposure for 19/28 min, respectively, slabs were removed and incubated with HCl in vitro over 120 s (pH 2, 2.3, 3). The resulting calcium and phosphate release was quantified photometrically. Slabs with and without a 30-min in situ pellicle served as controls. The modification of pellicle ultrastructure was evaluated by transmission electron microscopy (TEM). Results: Plant extracts modulated the erosion-protective properties of the native in situ pellicle in all test groups in a pH-dependent manner. The combination of R. nigrum leaves and Origanum enhanced the protective properties of the pellicle at all pH values; the administration of this preparation was comparable, yet superior, to the effect of the fluoridated mouth rinse. TEM images indicated that rinsing with R. nigrum leaves/Origanum yielded a distinctly thicker and more electron-dense pellicle. Conclusion: The combination of certain plant extracts offers a novel approach to the complementary prevention of dental erosion.

scholarly journals Экспериментальные модели сократительной активности миометрия

2020 ◽  
Author(s):  
A.A. Yakovleva ◽  
N.G. Pavlova
Keyword(s):  
In Silico ◽  
Contractile Activity ◽  
Experimental Models ◽  
Pacemaker Activity ◽  
Single View ◽  
Uterine Contractile ◽  
Experimental Approaches

Сократительная деятельность матки до настоящего времени остается актуальным вопросом фундаментальных исследований, поскольку отсутствуют единые представления о биомеханике маточного сокращения, необходимые для профилактики родового и акушерского травматизма. Цель работы - оценка ограничений и возможностей экспериментальных моделей, предназначенных для изучения сократительной активности миометрия. Методика. Основными экспериментальными подходами к изучению сократительной активности матки являлись исследования in vitro, in situ, in vivo, in silico, а также их сочетание. Результаты. В статье рассмотрены исследования, в которых использованы различные сочетания экспериментальных подходов, обсуждаются результаты, полученные при моделировании в экспериментах, обсуждаются результаты изучения синхронизации сокращения отделов матки на различных моделях, а также результаты исследования пейсмейкерной активности миометрия и возможность экстраполяции полученных данных на человека. В связи с активным развитием компьютерных технологий в статье поднимается вопрос об их использовании в моделировании сократительной активности матки человека. Заключение. Делается заключение, что комплексный подход, включающий электромиографические, биохимические и морфологические исследования в хроническом эксперименте, является наиболее адекватным для изучения сократительной активности миометрия и функционального состояния нормально развитых и отставших в развитии плодов, что позволит разработать комплексные методы профилактики родового и акушерского травматизма.Uterine contractile activity remains an important issue of fundamental research as there is no single view of the biomechanics of uterine contraction necessary for the prevention of parturition and obstetric trauma until now. The aim of the review was to assess advantages and limitations of experimental models described in the literature for study uterine contractile activity. At the present time main experimental approaches for study myometrium contractile activity are research in vitro, in situ, in vivo, in silico and the their combinations. The literature presents experimental approaches, different models of uterine contractions synchronization and study of myometrium pacemaker activity. Due to active development of computer technologies there is a need to model human uterine contractile activity with a simplified anatomy. The authors propose that combination of electromyographic, biochemical and morphological methods in chronic experiment is the most correct and appropriate direction for the assessment of the myometrium contractile activity and functional state of normally developed and growth restricted fetuses.

scholarly journals Thermo-Responsive Hydrogels Based on Methylcellulose/Persian Gum Loaded With Taxifolin Enhance Bone Regeneration: An in Vitro / in Vivo Study

2021 ◽  
Author(s):  
Zahra Sadat Sajadi-Javan ◽  
Jaleh Varshosaz ◽  
Mina Mirian ◽  
Maziar Manshaei ◽  
Atousa Aminzadeh
Keyword(s):  
Animal Studies ◽  
Bone Defects ◽  
Halloysite Nanotubes ◽  
Thermosensitive Hydrogel ◽  
Alizarin Red ◽  
The Impact ◽  
Responsive Hydrogels

Abstract In-situ forming hydrogels have gained noticeable attention to encapsulate osteogenic agents and regenerate irregular-shape bone defects. In this study, a novel thermosensitive hydrogel based on blended methylcellulose (MC) with Persian gum (PG) was fabricated and enriched with taxifolin (TAX) loaded halloysite nanotubes (HNTs) to enhance mechanical and biological characteristics of the hydrogel in bone tissue engineering. The injectability, mechanical and rheological tests were performed for different hydrogel formulations containing 0.25-1.5 w/v% PG and 1-7 w/v% HNTs. Also, to evaluate the impact of PG and HNTs on hydrogel behavior, the degradation rate and swelling degree of hydrogels were assessed. The optimized MC/PG/HNTs hydrogel containing 1% PG and 3% HNTs (MC/PG-1/HNTs 3%) was easily injectable and gelled rapidly at physiological temperature, while it had the highest mechanical strength due to the existence of PG and HNTs. In vitro release study of TAX from this system also revealed more sustained release compared to HNTs-TAX nanoparticles. Furthermore, the interaction of cells with hydrogel and osteo-conductivity was studied using osteoblast-like cells (MG-63). Results showed higher cell adhesion, proliferation, and gene expression for MC/PG-1/HNTs-TAX hydrogel compared to MC/PG-1 and MC/PG-1/HNTs 3% possibly due to the synergic effect of HNTs and TAX. In addition, Alizarin Red S staining and alkaline phosphatase measurements indicated that the existence of HNTs-TAX promoted osteogenic differentiation. Eventually, animal studies on the femoral defects indicated improved remedy when using the MC/PG-1/HNTs-TAX hydrogel carrying MG-63 cells.

Does Finishing and Polishing of Restorative Materials Affect Bacterial Adhesion and Biofilm Formation? A Systematic Review

2018 ◽  
Vol 43 (1) ◽  
pp. E37-E52 ◽  
Author(s):  
DAM Dutra ◽  
GKR Pereira ◽  
KZ Kantorski ◽  
LF Valandro ◽  
FB Zanatta
Keyword(s):  
Systematic Review ◽  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Surface Characteristics ◽  
Periodontal Inflammation ◽  
Restorative Materials ◽  
The Impact

SUMMARY Biofilm (bacterial plaque) accumulation on the surface of restorative materials favors the occurrence of secondary caries and periodontal inflammation. Surface characteristics of restorations can be modified by finishing and/or polishing procedures and may affect bacterial adhesion. The aim of this systematic review was to characterize how finishing and polishing methods affect the surface properties of different restorative materials with regard to bacterial adhesion and biofilm formation. Searches were carried out in MEDLINE-PubMed, EMBASE, Cochrane-CENTRAL, and LILACS databases. From 2882 potential articles found in the initial searches, only 18 met the eligible criteria and were included in this review (12 with in vitro design, four with in situ design, and two clinical trials). However, they presented high heterogeneity regarding materials considered and methodology for evaluating the desired outcome. Risk bias analysis showed that only two studies presented low risk (whereas 11 showed high and five showed medium risk). Thus, only descriptive analyses considering study design, materials, intervention (finishing/polishing), surface characteristics (roughness and surface free energy), and protocol for biofilm formation (bacterial adhesion) could be performed. Some conclusions could be drawn: the impact of roughness on bacterial adhesion seems to be related not to a roughness threshold (as previously believed) but rather to a range, the range of surface roughness among different polishing methods is wide and material dependent, finishing invariably creates a rougher surface and should always be followed by a polishing method, each dental material requires its own treatment modality to obtain and maintain as smooth a surface as possible, and in vitro designs do not seem to be powerful tools to draw relevant conclusions, so in vivo and in situ designs become strongly recommended.

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