scholarly journals Human Oligodendrocytes and Myelin In Vitro to Evaluate Developmental Neurotoxicity

2021 ◽  
Vol 22 (15) ◽  
pp. 7929
Author(s):  
Megan Chesnut ◽  
Thomas Hartung ◽  
Helena Hogberg ◽  
David Pamies

Neurodevelopment is uniquely sensitive to toxic insults and there are concerns that environmental chemicals are contributing to widespread subclinical developmental neurotoxicity (DNT). Increased DNT evaluation is needed due to the lack of such information for most chemicals in common use, but in vivo studies recommended in regulatory guidelines are not practical for the large-scale screening of potential DNT chemicals. It is widely acknowledged that developmental neurotoxicity is a consequence of disruptions to basic processes in neurodevelopment and that testing strategies using human cell-based in vitro systems that mimic these processes could aid in prioritizing chemicals with DNT potential. Myelination is a fundamental process in neurodevelopment that should be included in a DNT testing strategy, but there are very few in vitro models of myelination. Thus, there is a need to establish an in vitro myelination assay for DNT. Here, we summarize the routes of myelin toxicity and the known models to study this particular endpoint.

2020 ◽  
Vol 20 ◽  
Author(s):  
Nur Najmi Mohamad Anuar ◽  
Nurul Iman Natasya Zulkafali ◽  
Azizah Ugusman

: Matrix metalloproteinases (MMPs) are a group of zinc-dependent metallo-endopeptidase that are responsible towards the degradation, repair and remodelling of extracellular matrix components. MMPs play an important role in maintaining a normal physiological function and preventing diseases such as cancer and cardiovascular diseases. Natural products derived from plants have been used as traditional medicine for centuries. Its active compounds, such as catechin, resveratrol and quercetin, are suggested to play an important role as MMPs inhibitors, thereby opening new insights into their applications in many fields, such as pharmaceutical, cosmetic and food industries. This review summarises the current knowledge on plant-derived natural products with MMP-modulating activities. Most of the reviewed plant-derived products exhibit an inhibitory activity on MMPs. Amongst MMPs, MMP-2 and MMP-9 are the most studied. The expression of MMPs is inhibited through respective signalling pathways, such as MAPK, NF-κB and PI3 kinase pathways, which contribute to the reduction in cancer cell behaviours, such as proliferation and migration. Most studies have employed in vitro models, but a limited number of animal studies and clinical trials have been conducted. Even though plant-derived products show promising results in modulating MMPs, more in vivo studies and clinical trials are needed to support their therapeutic applications in the future.


2009 ◽  
Vol 3 (4) ◽  
Author(s):  
Fangmin Xu ◽  
Kevin Hart ◽  
Claire E. Flanagan ◽  
John C. Nacker ◽  
Roham Moftakhar ◽  
...  

The treatment of cerebral aneurysms is frequently accomplished via endovascular delivery of metal coils in order to occlude the aneurysm and prevent rupture. This procedure involves imprecise packing of large lengths of wire into the aneurysm and often results in high rates of aneurysm recanalization. Over time, this incomplete aneurysm occlusion can lead to aneurysm enlargement, which may have fatal consequences. This report describes the fabrication and preliminary testing of a novel aneurysm occlusion device composed of a single metal coil surrounded by a biocompatible polymer shell. These coil-in-shell devices were tested under flow conditions in synthetic in vitro models of saccular aneurysms and deployed in vivo in a short-term porcine aneurysm model to study occlusion efficacy. A single nickel titanium shape memory wire was used to deploy a biocompatible, elastic polymeric shell, leading to aneurysmal sac filling in both in vitro and in vivo aneurysm models. The deployment of this coil-in-shell device in synthetic aneurysm models in vitro resulted in varying degrees of aneurysm occlusion, with less than 2% of trials resulting in significant leakage of fluid into the aneurysm. Meanwhile, in vivo coil-in-shell device implantation in a porcine aneurysm model provided proof-of-concept for successful occlusion, as both aneurysms were completely occluded by the devices. Both in vitro and in vivo studies demonstrated that this coil-in-shell device may be attractive as an alternative to traditional coil embolization methods in some cases, allowing for a more precise and controlled aneurysm occlusion.


Author(s):  
Aloisio Cunha de Carvalho ◽  
Leoni Villano Bonamin

Background: Several reviews about phytotherapy and homeopathy have been published in the last years, including Viscum album (VA.L). VA is a parasite plant whose extract has anti-cancer proprieties and is used alone or in combination with conventional chemotherapy. Methods: We performed a systematic review about the in vivo and in vitro models described in the literature, including veterinary clinical trials. The literature was consulted from Pubmed database. Results: There are several kinds of pharmaceutical preparations about VA and their active principles used in experimental studies, lectin being frequently studied (alone or as an extract compound). More than 50% of available literature about VA is related to the lectin effects. On the other hand, the effects of viscotoxins are less studied. Among the in vivo experimental studies about VA and its compounds, the B16 murine melanoma is the most used model, followed by Ehrlich, Walker and Dalton tumors. The results point to the apoptotic effects, metastasis control and tumor regression. Some veterinary clinical studies about the use of VA in the treatment of sarcoid, fibrosarcoma and neuroblastoma are quoted in literature too, with interesting results. Considering the in vitro models, our review revealed that NALM6 leukemia cells, B16 melanoma and NC1-H460 lung carcinoma were the most studied tumor models, apoptosis signals being the most important findings. Only one study verified immunoglobulin and interleukin production. All consulted papers were related to phytotherapy preparations only. Conclusions: Although the literature about the anti-cancer activity of VA extract and its lectins is enough, there is a marked lack of information about viscotoxin activities and about the effects of homeopathic preparations of this plant on animal tumors and on in vitro cultivated tumor cells.


2020 ◽  
Vol 22 (8) ◽  
Author(s):  
Barbara De Berardis ◽  
Magda Marchetti ◽  
Anna Risuglia ◽  
Federica Ietto ◽  
Carla Fanizza ◽  
...  

AbstractIn recent years, the introduction of innovative low-cost and large-scale processes for the synthesis of engineered nanoparticles with at least one dimension less than 100 nm has led to countless useful and extensive applications. In this context, gold nanoparticles stimulated a growing interest, due to their peculiar characteristics such as ease of synthesis, chemical stability and optical properties. This stirred the development of numerous applications especially in the biomedical field. Exposure of manufacturers and consumers to industrial products containing nanoparticles poses a potential risk to human health and the environment. Despite this, the precise mechanisms of nanomaterial toxicity have not yet been fully elucidated. It is well known that the three main routes of exposure to nanomaterials are by inhalation, ingestion and through the skin, with inhalation being the most common route of exposure to NPs in the workplace. To provide a complete picture of the impact of inhaled gold nanoparticles on human health, in this article, we review the current knowledge about the physico-chemical characteristics of this nanomaterial, in the size range of 1–100 nm, and its toxicity for pulmonary structures both in vitro and in vivo. Studies comparing the toxic effect of NPs larger than 100 nm (up to 250 nm) are also discussed.


2019 ◽  
Vol 30 (1) ◽  
pp. 16-21 ◽  
Author(s):  
T. Aghaloo ◽  
J.J. Kim ◽  
T. Gordon ◽  
H.P. Behrsing

Traditional tobacco products have well-known systemic and local oral effects, including inflammation, vasoconstriction, delayed wound healing, and increased severity of periodontal disease. Specifically in the oral cavity and the lung, cigarette smoking produces cancer, increased infectivity, acute and chronic inflammation, changes in gene expression in epithelial lining cells, and microbiome changes. In recent years, cigarette smoking has greatly decreased in the United States, but the use of new tobacco products has gained tremendous popularity. Without significant knowledge of the oral sequelae of products such as electronic cigarettes, researchers must evaluate current in vitro and in vivo methods to study these agents, as well as develop new tools to adequately study their effects. Some in vitro testing has been performed for electronic cigarettes, including toxicologic models and assays, but these mostly study the effect on the respiratory tract. Recently, direct exposure of the aerosol to in vitro 3-dimensional tissue constructs has been performed, demonstrating changes in cell viability and inflammatory cytokines. For in vivo studies, a universal e-cigarette testing machine or standard vaping regime is needed. A standard research electronic cigarette has recently been developed by the National Institute of Drug Abuse, and other devices delivering aerosols with different nicotine concentrations are becoming available. One of the biggest challenges in this research is keeping up with the new products and the rapidly changing technologies in the industry.


1979 ◽  
Vol 41 (2) ◽  
pp. 403-405 ◽  
Author(s):  
K. M. Weber ◽  
D. D. Leaver ◽  
A. G. Wedd

The stability of potassium tetrathiomolybdate was studied in vitro using solutions with molybdenum, hydrogen ion and phosphate concentrations similar to those normally found in the rumen. Under these conditions K2[MoS4] hydrolysed rapidly and as a result the solution contained [MoS4]2−, [MoOS3]2−, [MoO2S2]2−, [HS]− and H2S in equilibrium. In view of this hydrolysis, in vivo studies of thiomolybdate on copper metabolism of sheep should not exclude the possibility that either sulphide or molybdate is responsible for any observed effect.


2019 ◽  
Vol 17 (3) ◽  
pp. 247-267 ◽  
Author(s):  
Muneeb U. Rehman ◽  
Adil Farooq Wali ◽  
Anas Ahmad ◽  
Sheeba Shakeel ◽  
Saiema Rasool ◽  
...  

Nature has bestowed mankind with surplus resources (natural products) on land and water. Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. These natural products have been experimentally documented to possess various biological properties such as antioxidant, anti-inflammatory and anti-apoptotic activities. In vitro and in vivo studies have further established the usefulness of natural products in various preclinical models of neurodegenerative disorders. Natural products include phytoconstituents, like polyphenolic antioxidants, found in herbs, fruits, nuts, vegetables and also in marine and freshwater flora. These phytoconstituents may potentially suppress neurodegeneration and improve memory as well as cognitive functions of the brain. Also, they are known to play a pivotal role in the prevention and cure of different neurodegenerative diseases, such as Alzheimer’s disease, epilepsy, Parkinson’s disease and other neuronal disorders. The large-scale neuro-pharmacological activities of natural products have been documented due to the result of either the inhibition of inflammatory processes, or the up-regulation of various cell survival proteins or a combination of both. Due to the scarcity of human studies on neuroprotective effects of natural products, this review focuses on the various established activities of natural products in in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications using the available knowledge in the literature.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Therina Du Toit ◽  
Amanda C Swart

Abstract The metabolism of 11β-hydroxyandrostenedione (11OHA4), a major adrenal C19 steroid, was first characterised in our in vitro prostate models showing that 11OHA4, catalysed by 11βHSDs, 17βHSDs and 5α-reductases, yields potent androgens, 11keto-testosterone (11KT) and 11keto-dihydrotestosterone (11KDHT) in the 11OHA4-pathway [1]. Findings have since led to the analysis of C11-oxy steroids in PCOS, CAH and 21OHD. However, the only circulating C11-oxy steroids included to date have been 11OHA4, 11keto-androstenedione (11KA4), 11β-hydroxytestosterone (11OHT) and 11KT, with 11KT reported as the only potent androgen produced from 11OHA4. We have identified higher levels of 11KDHT compared to 11KT in prostate cancer tissue and benign prostatic hyperplasia tissue and serum, with data suggesting impeded glucuronidation of the C11-oxy androgens [2,3]. The assessment of 11KDHT and the inactivation/conjugation of the C11-oxy steroids in clinical conditions is therefore crucial. We investigated the metabolism of testosterone, 11KT, 11OHT, dihydrotestosterone, 11KDHT and 11OHDHT in JEG-3 placenta choriocarcinoma, MCF-7 BUS and T-47D breast cancer cells, focusing on glucuronidation and sulfation. Steroids were assayed at 1 µM and metabolites were quantified using UPC2-MS/MS. Conjugated steroids were not detected in JEG-3 cells with DHT (0.6 µM remaining) metabolised to 5α-androstane-3α,17β-diol and androsterone (AST), and 11KDHT (0.9 µM remaining) to 11OHAST and 11KAST. 11OHA4 was converted to 11KA4 (12%) and 11KT (2.5%); and 11KT to 11KDHT (14%). In MCF-7 BUS cells, DHT was significantly glucuronidated, whereas 11KDHT was not. 11KAST was the only steroid in the MCF-7 BUS and T-47D cells that was significantly sulfated (p<0.05). In parallel we investigated sulfation in the LNCaP prostate model. Comparing sulfated to glucuronidated levels, only DHT was sulfated, 26%. Analysis showed that C19 steroids were significantly conjugated (glucuronidated + sulfated) compared to the C11-oxy C19 steroids. As there exists an intricate interplay between steroid production and inactivation, impacting pre- and post-receptor activation, efficient conjugation would limit adverse downstream effects. Our data demonstrates the production and impeded conjugation of active C11-oxy C19 steroids, allowing the prolonged presence of androgenic steroids in the cellular microenvironment. Identified for the first time is the 11OHA4-pathway in placenta and breast cancer cells, and the sulfation of 11KAST. Characterising steroidogenic pathways in in vitro models paves the direction for in vivo studies associated with characterising clinical disorders and disease, which the C11-oxy C19 steroids and their intermediates, including inactivated and conjugated end-products, have highlighted. [1] Bloem, et al. JSBMB 2015, 153; [2] Du Toit & Swart. MCE 2018, 461; [3] Du Toit & Swart, JSBMB 2020, 105497.


Author(s):  
Md. Habibur Rahman ◽  
Rokeya Akter ◽  
Mohammad Amjad Kamal

: Nature has bestowed humanity through additional resources natural products (NPs) on earth with water. However, NPs have a significant function in the avoidance of disease by boosting health in humans as well as animals. These NPs have been scientifically acknowledged to have a range of biological characteristics like antioxidant, anti-inflammatory actions. Both In vitro and in vivo studies have more recognised the convenience of NPs in different preclinical models of neurodegenerative disorders. Moreover, most NPs comprise phytoconstituents, including polyphenolic antioxidants; originate in herbs, fruits, nuts, vegetables as well as also in marine with freshwater flora. These phytoconstituents might actively repress neuro-degeneration and recover memory as like cognitive actions of the brain. Moreover, they are well recognized to participate in an essential position in the prevention like heal of different neurodegenerative diseases, like Alzheimer’s disease, Parkinson’s disease, epilepsy, and additional neuronal disorders. In general, the large-scale neuro-pharmacological actions of NPs have been familiar owing to the consequence of also the inhibition of inflammatory processes, or the up-regulation of various cell endurance proteins or a mixture of together. Owing to the shortage of human studies on neuroprotective belongings of NPs, this review highlights a variety of documented actions of NPs in vitro and in vivo preclinical models and their possible neuro-protection applications by the accessible awareness in writing.


Molecules ◽  
2019 ◽  
Vol 24 (10) ◽  
pp. 1913 ◽  
Author(s):  
Bahare Salehi ◽  
Lorene Armstrong ◽  
Antonio Rescigno ◽  
Balakyz Yeskaliyeva ◽  
Gulnaz Seitimova ◽  
...  

This work is an updated snapshot of Lamium plants and their biological activities. The main features of the plant are described and the components of its essential oils are summarized. The traditional medicinal uses of Lamium plants has been reported. The presence of these chemicals i.e., hydroxycinnamic acids, iridoids, secoiridoids, flavonoids, anthocyanins, phenylpropanoids, phytoecdysteroids, benzoxazinoids, betaine can provide biological activities. After the discussion of antioxidant properties documented for Lamium plants, the biological activities, studied using in vitro models, antimicrobial, antiviral, anti-inflammatory, anti-nociceptive activity, and pain therapy and cytotoxicity and cytoprotective activity are here described and discussed. Finally, targeted examples of in vivo studies are reported.


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